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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

Sensing the gas metal arc welding process  

SciTech Connect (OSTI)

Control of gas metal arc welding (GMAW) requires real-time sensing of the process. Three sensing techniques for GMAW are being developed at the Idaho National Engineering Laboratory (INEL). These are (1) noncontacting ultrasonic sensing using a laser/EMAT (electromagnetic acoustic transducer) to detect defects in the solidified weld on a pass-bypass basis, (2) integrated optical sensing using a CCD camera and a laser stripe to obtain cooling rate and weld bead geometry information, and (3) monitoring fluctuations in digitized welding voltage data to detect the mode of metal droplet transfer and assure that the desired mass input is achieved.

Carlson, N.M.; Johnson, J.A.; Smartt, H.B.; Watkins, A.D.; Larsen, E.D.; Taylor, P.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States); Waddoups, M.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

1992-10-01T23:59:59.000Z

2

Sensing the gas metal arc welding process  

SciTech Connect (OSTI)

Control of gas metal arc welding (GMAW) requires real-time sensing of the process. Three sensing techniques for GMAW are being developed at the Idaho National Engineering Laboratory (INEL). These are (1) noncontacting ultrasonic sensing using a laser/EMAT (electromagnetic acoustic transducer) to detect defects in the solidified weld on a pass-bypass basis, (2) integrated optical sensing using a CCD camera and a laser stripe to obtain cooling rate and weld bead geometry information, and (3) monitoring fluctuations in digitized welding voltage data to detect the mode of metal droplet transfer and assure that the desired mass input is achieved.

Carlson, N.M.; Johnson, J.A.; Smartt, H.B.; Watkins, A.D.; Larsen, E.D.; Taylor, P.L. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Waddoups, M.A. (Idaho National Engineering Lab., Idaho Falls, ID (United States))

1992-01-01T23:59:59.000Z

3

Optimization of Weld Bead Penetration in Pulsed Gas Metal Arc Welding using Genetic Algorithm  

E-Print Network [OSTI]

Abstract — The weld quality is highly influenced by various process parameters involved in the process. This can be achieved by meeting quality requirements of bead geometry. Inadequate depth of penetration will contribute to failure of the welded structure. This paper presents the development of genetic algorithm model for the optimization of depth of penetration of weld bead geometry in pulsed gas metal arc welding process. The model is based on experimental data. The thickness of the plate, pulse frequency, wire feed rate, wire feed rate/travel speed ratio, and peak current have been considered as the process parameters to maximize the bead penetration depth. Optimization of process parameters was done using GA. The developed model is then compared with experimental results and it is found that the results obtained from genetic algorithm model are accurate. The optimal process parameters gave a value of 5.314 for depth of penetration which demonstrates an accuracy of 1.33 % and thus the effectiveness of the model presented. The obtained results help in selecting quickly the process parameters to achieve the desired quality. Keywords—Genetic algorithm, Pulsed GMA welding, Welding parameters, Depth of penetration, Regression mode I.

K. Manikya Kanti; P. Srinivasa Rao; G. Ranga Janardhana

4

Gas metal arc welding of duplex stainless steel using flux cored wire  

SciTech Connect (OSTI)

The effect of chemical compositions and welding parameters on pitting corrosion resistance and notch toughness of duplex stainless steel weld metals by FCAW was investigated. And the effect of welding parameters on hot cracking susceptibility of the FCAW weld metals was also studied. Pitting corrosion resistance was improved with the increase of Cr, Mo and N content in the weld metal, and it was also proved that the corrosion resistance was greatly affected by welding heat input. Hot cracking susceptibility of the weld metal was increased with the increase of welding current and welding speed.

Maruyama, T.; Ogawa, T.; Nishiyama, S.; Ushijima, A.; Yamashita, K. [Kobe Steel, Ltd., Fujisawa (Japan)

1994-12-31T23:59:59.000Z

5

Oxygen and Nitrogen Contamination During Arc Welding  

E-Print Network [OSTI]

) ) : ,- Oxygen and Nitrogen Contamination During Arc Welding T. W. Eagar Department of }faterials, mechanisms, and expected levels of oxygen and nitrogen contamination during gas tungsten arc, gas metal arc indicating the importance of dec9mposition of SiOz into silicon monoxide and oxygen are presented, indicating

Eagar, Thomas W.

6

In-situ repairs of pipelines using metal arc welding under oil (MAW-UO) aided by eddy current crack detection  

Science Journals Connector (OSTI)

Metal arc welding under oil (MAW-UO) is a new process developed to make in-situ internal repairs of in-service oil industry pipelines tanks and vessels without the need to evacuate the service from the containing fluid. High nickel alloy welding wires were used to produce a tough relatively soft austenitic weld metal; with reduced weld metal hardness porosity residual strain and cracking susceptibility. Eddy current sensors were able to detect cracks under oil which then can be repaired in-situ using MAW-UO. The in-situ under oil crack detection and arc weld repair process will be described.

2012-01-01T23:59:59.000Z

7

Measurement and finite element analysis of temperature distribution in arc welding process  

Science Journals Connector (OSTI)

This presentation describes both the experimental measurement and finite element analysis used to study the temperature distribution during a metal inert gas (MIG) welding process, including the cooling down period. Welding was carried out on ... Keywords: FEA, MIG welding, arc welding, cracking, finite element analysis, metal inert gas welding, residual stress, simulation, temperature distribution, weldment temperature

C. K. Lee; J. Candy; C. P. H. Tan

2004-12-01T23:59:59.000Z

8

Welding arc initiator  

DOE Patents [OSTI]

An improved inert gas shielded tungsten arc welder is disclosed of the type wherein a tungsten electrode is shielded within a flowing inert gas, and, an arc, following ignition, burns between the energized tungsten electrode and a workpiece. The improvement comprises in combination with the tungsten electrode, a starting laser focused upon the tungsten electrode which to ignite the electrode heats a spot on the energized electrode sufficient for formation of a thermionic arc. Interference problems associated with high frequency starters are thus overcome. 3 figs.

Correy, T.B.

1989-05-09T23:59:59.000Z

9

Welding arc initiator  

DOE Patents [OSTI]

An improved inert gas shielded tungsten arc welder is disclosed of the type wherein a tungsten electrode is shielded within a flowing inert gas, and, an arc, following ignition, burns between the energized tungsten electrode and a workpiece. The improvement comprises in combination with the tungsten electrode, a starting laser focused upon the tungsten electrode which to ignite the electrode heats a spot on the energized electrode sufficient for formation of a thermionic arc. Interference problems associated with high frequency starters are thus overcome.

Correy, Thomas B. (Richland, WA)

1989-01-01T23:59:59.000Z

10

Welding of cast A359/SiC/10p metal matrix composites  

E-Print Network [OSTI]

arc welding GTAW Gas tungsten arc welding HAZ Heat affected zone HF High frequency MMC Metal matrix composite MMCs Metal matrix composites NDE Non-destructive examination SAW Submerged arc welding SMAW Shielded metal arc... limited their applications. Further, the use of composite materials requires us to stay from the established processes and areas of practice that were relevant to more conventional engineering materials. Except for gas tungsten arc welding (GTAW...

Kothari, Mitul Arvind

2005-11-01T23:59:59.000Z

11

Plutonium metal and oxide container weld development and qualification  

SciTech Connect (OSTI)

Welds were qualified for a container system to be used for long-term storage of plutonium metal and oxide. Inner and outer containers are formed of standard tubing with stamped end pieces gas-tungsten-arc (GTA) welded onto both ends. The weld qualification identified GTA parameters to produce a robust weld that meets the requirements of the Department of Energy standard DOE-STD-3013-94, ``Criteria for the Safe Storage of Plutonium Metals and Oxides.``

Fernandez, R.; Horrell, D.R.; Hoth, C.W.; Pierce, S.W.; Rink, N.A.; Rivera, Y.M.; Sandoval, V.D.

1996-01-01T23:59:59.000Z

12

Visible Light Emissions during Gas Tungsten Arc Welding and Its Application to Weld  

E-Print Network [OSTI]

\\ Visible Light Emissions during Gas Tungsten· Arc Welding and Its Application to Weld Image. EAGAR ABSTRACT. An experimental study was carried out to map the light emissions from a gas tungsten arc. The emissions were found to be dramat- ically different with different shielding gases, welding current and base

Eagar, Thomas W.

13

Welding of HSLA-100 steel using ultra low carbon bainitic weld metal to eliminate preheating  

SciTech Connect (OSTI)

Advanced high strength steels such as the Navy`s HSLA-100 and HSLA-80 contain sufficiently low carbon levels to be weldable without preheating. Unfortunately, commercial filler metals specifically designed to weld these steels without costly preheating have not yet been developed. The objective of this paper is to show that the Navy`s advanced steels can be welded by gas metal-arc (GMAW) and gas tungsten-arc welding (GTAW) without preheating by using filler metal compositions that produce weld metal with an ultra-low carbon bainitic (ULCB) microstructure. Filler metals were fabricated from vacuum induction melted (VIM) ingots containing ultra-low levels of C, O and N. HSLA-100 plate and plate from the VIM ingots were welded by both GMAW and GTAW with Ar-5% CO{sub 2} shielding gas using welding conditions to achieve cooling times from 800 to 500 C (t{sub 8-5}) from 35 to 14 sec. Weld metal tensile, hardness and CVN impact toughness testing as well as microstructural studies using transmission electron microscopy were conducted. The ULCB weld metal was relatively insensitive to cooling rate, resulting in good strength and toughness values over a wide range of t{sub 8-5} cooling times. Filler metal compositions which met the mechanical property requirements for HSLA-100, HSLA-80 and HSLA-65 weld metal were developed.

Devletian, J.H.; Singh, D.; Wood, W.E. [Oregon Graduate Inst. of Science and Technology, Portland, OR (United States)

1996-12-31T23:59:59.000Z

14

Electrochemical Testing of Gas Tungsten ARC Welded and Reduced Pressure Electron Beam Welded Alloy 22  

SciTech Connect (OSTI)

Alloy 22 (N06022) is the material selected for the fabrication of the outer shell of the nuclear waste containers for the Yucca Mountain high-level nuclear waste repository site. A key technical issue in the waste package program has been the integrity of the container weld joints. The currently selected welding process for fabricating and sealing the containers is the traditional gas tungsten arc welding (GTAW) or TIC method. An appealing faster alternative technique is reduced pressure electron beam (RPEB) welding. It was of interest to compare the corrosion properties of specimens prepared using both types of welding techniques. Standard electrochemical tests were carried on GTAW and RPEB welds as well as on base metal (non-welded) to determine their relative corrosion behavior in simulated concentrated water (SCW) at 90 C (alkaline), 1 M HCI at 60 C (acidic) and 1 M NaCl at 90 C (neutral) solutions. Results show that for all practical purposes, the three tested materials had the same electrochemical behavior in the three tested electrolytes.

S. Daniel Day; Frank M.G. Wong; Steven R. Gordon; Lana L. Wong; Raul B. Rebak

2006-05-08T23:59:59.000Z

15

A Glove Box Enclosed Gas-Tungsten Arc Welding System  

SciTech Connect (OSTI)

This report describes an inert atmosphere enclosed gas-tungsten arc welding system which has been assembled in support of the MC2730, MC2730A and MC 3500 Radioisotope Thermoelectric Generator (RTG) Enhanced Surveillance Program. One goal of this program is to fabricate welds with microstructures and impurity levels which are similar to production heat source welds previously produced at Los Alamos National Laboratory and the Mound Facility. These welds will subsequently be used for high temperature creep testing as part of the overall component lifetime assessment. In order to maximize the utility of the welding system, means for local control of the arc atmosphere have been incorporated and a wide range of welding environments can easily be evaluated. The gas-tungsten arc welding system used in the assembly is computer controlled, includes two-axis and rotary motion, and can be operated in either continuous or pulsed modes. The system can therefore be used for detailed research studies of welding impurity effects, development of prototype weld schedules, or to mimic a significant range of production-like welding conditions. Fixturing for fabrication of high temperature creep test samples have been designed and constructed, and weld schedules for grip-tab and test welds have been developed. The microstructure of these welds have been evaluated and are consistent with those used during RTG production.

Reevr, E, M; Robino, C.V.

1999-07-01T23:59:59.000Z

16

Effect of Microstructure on Mechanical Properties of High Strength Steel Weld Metals  

E-Print Network [OSTI]

using for example gas tungsten arc welding (GTAW). However as strength levels increase it becomes more difficult to fulfil impact toughness requirements with flexible and productive welding methods such as shielded metal arc welding (SMAW), flux cored... . Little effects are seen on the cross sectional area of each weld bead deposited with increase in interpass temperature but the proportion of recrystallised area increases [12]. By eliminating the columnar microstructure, hardness becomes more uniform...

Keehan, Enda

2004-01-01T23:59:59.000Z

17

Stainless steel submerged arc weld fusion line toughness  

SciTech Connect (OSTI)

This effort evaluated the fracture toughness of austenitic steel submerged-arc weld (SAW) fusion lines. The incentive was to explain why cracks grow into the fusion line in many pipe tests conducted with cracks initially centered in SAWS. The concern was that the fusion line may have a lower toughness than the SAW. It was found that the fusion line, Ji. was greater than the SAW toughness but much less than the base metal. Of greater importance may be that the crack growth resistance (JD-R) of the fusion line appeared to reach a steady-state value, while the SAW had a continually increasing JD-R curve. This explains why the cracks eventually turn to the fusion line in the pipe experiments. A method of incorporating these results would be to use the weld metal J-R curve up to the fusion-line steady-state J value. These results may be more important to LBB analyses than the ASME flaw evaluation procedures, since there is more crack growth with through-wall cracks in LBB analyses than for surface cracks in pipe flaw evaluations.

Rosenfield, A.R.; Held, P.R.; Wilkowski, G.M. [Battelle, Columbus, OH (United States)

1995-04-01T23:59:59.000Z

18

Surface preparation effects on GTA (gas tungsten arc) weld penetration in JBK-75 stainless steel  

SciTech Connect (OSTI)

The results of a study are reported here on the effects of surface preparation on the shape of GTA welds on JBK-75, an austenitic precipitation hardenable stainless steel similar to A286. Minor changes in surface (weld groove) preparation produced substantial changes in the penetration characteristics and welding behavior of this alloy. Increased and more consistent weld penetration (higher d/w ratios) along with improved arc stability and less arc wander result from wire brushing and other abrasive surface preparations, although chemical and machining methods did not produce any improvement in penetration. Abrasive treatments roughen the surface, increase the surface area, and increase the surface oxide thickness. The increased weld d/w ratio is attributed to oxygen added to the weld pool from the surface oxide on the base metal. The added oxygen alters the surface-tension driven fluid flow pattern in the weld pool. Similar results were observed with changes in filler wire surface oxide thickness, caused by changes in wire production conditions. 15 refs., 14 figs., 4 tabs.

Campbell, R.D.; Heiple, C.R.; Sturgill, P.L.; Robertson, A.M.; Jamsay, R.

1989-01-01T23:59:59.000Z

19

The effective spectral irradiance of ultra-violet radiations from inert-gas-shielded welding processes in relation to the ARC current density  

E-Print Network [OSTI]

lamp filaments, the electrodes of an electric arc, and molten metals of high melting point. The emission of an incandescent object is due to its temperature and depends little upon the chemical nature of the radiator. The Stefan- 13 Boltzmann law... is automatically fed by the welding machine into the weld puddle. Metal is transferred through the arc plasma to the base material being welded. The wire is of the same metallic composition as the base metal, and generally the same diameter is used for most...

DeVore, Robin Kent

1973-01-01T23:59:59.000Z

20

E-Print Network 3.0 - arc welding dynamic Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a system IO board; arc sensor interface board for weld seam tracking... inverter power source renders possible ... Source: Ang Jr.,, Marcelo H. - Department of Mechanical...

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Causal Factors of Weld Porosity in Gas Tungsten Arc Welding of Powder Metallurgy Produced Titanium Alloys  

SciTech Connect (OSTI)

ORNL undertook an investigation using gas tungsten arc (GTA) welding on consolidated powder metallurgy (PM) titanium (Ti) plate, to identify the causal factors behind observed porosity in fusion welding. Tramp element compounds of sodium and magnesium, residual from the metallothermic reduction of titanium chloride used to produce the titanium, were remnant in the starting powder and were identified as gas forming species. PM-titanium made from revert scrap where sodium and magnesium were absent, showed fusion weld porosity, although to a lesser degree. We show that porosity was attributable to hydrogen from adsorbed water on the surface of the powders prior to consolidation. The removal / minimization of both adsorbed water on the surface of titanium powder and the residues from the reduction process prior to consolidation of titanium powders, are critical to achieve equivalent fusion welding success similar to that seen in wrought titanium produced via the Kroll process.

Muth, Thomas R [ORNL; Yamamoto, Yukinori [ORNL; Frederick, David Alan [ORNL; Contescu, Cristian I [ORNL; Chen, Wei [ORNL; Lim, Yong Chae [ORNL; Peter, William H [ORNL; Feng, Zhili [ORNL

2013-01-01T23:59:59.000Z

22

Method for gas-metal arc deposition  

DOE Patents [OSTI]

Method and apparatus for gas-metal arc deposition of metal, metal alloys, and metal matrix composites. The apparatus contains an arc chamber for confining a D.C. electrical arc discharge, the arc chamber containing an outlet orifice in fluid communication with a deposition chamber having a deposition opening in alignment wiht the orifice for depositing metal droplets on a coatable substrate. Metal wire is passed continuously into the arc chamber in alignment with the orifice. Electric arcing between the metal wire anode and the orifice cathode produces droplets of molten metal from the wire which pass through the orifice and into the deposition chamber for coating a substrate exposed at the deposition opening. When producing metal matrix composites, a suspension of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets to produce a uniform mixture which then coats the exposed substrate with a uniform metal matrix composite.

Buhrmaster, Carol L. (Corning, NY); Clark, Denis E. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID)

1990-01-01T23:59:59.000Z

23

Method for gas-metal arc deposition  

DOE Patents [OSTI]

Method and apparatus for gas-metal arc deposition of metal, metal alloys, and metal matrix composites are disclosed. The apparatus contains an arc chamber for confining a D.C. electrical arc discharge, the arc chamber containing an outlet orifice in fluid communication with a deposition chamber having a deposition opening in alignment with the orifice for depositing metal droplets on a coatable substrate. Metal wire is passed continuously into the arc chamber in alignment with the orifice. Electric arcing between the metal wire anode and the orifice cathode produces droplets of molten metal from the wire which pass through the orifice and into the deposition chamber for coating a substrate exposed at the deposition opening. When producing metal matrix composites, a suspension of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets to produce a uniform mixture which then coats the exposed substrate with a uniform metal matrix composite. 1 fig.

Buhrmaster, C.L.; Clark, D.E.; Smartt, H.B.

1990-11-13T23:59:59.000Z

24

Apparatus for gas-metal arc deposition  

DOE Patents [OSTI]

Apparatus for gas-metal arc deposition of metal, metal alloys, and metal matrix composites. The apparatus contains an arc chamber for confining a D.C. electrical arc discharge, the arc chamber containing an outlet orifice in fluid communication with a deposition chamber having a deposition opening in alignment with the orifice for depositing metal droplets on a coatable substrate. Metal wire is passed continuously into the arc chamber in alignment with the orifice. Electric arcing between the metal wire anode and the orifice cathode produces droplets of molten metal from the wire which pass through the orifice and into the deposition chamber for coating a substrate exposed at the deposition opening. When producing metal matrix composites, a suspenion of particulates in an inert gas enters the deposition chamber via a plurality of feed openings below and around the orifice so that reinforcing particulates join the metal droplets to produce a uniform mixture which then coats the exposed substrate with a uniform metal matrix composite.

Buhrmaster, Carol L. (Corning, NY); Clark, Denis E. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID)

1991-01-01T23:59:59.000Z

25

Metals purification by improved vacuum arc remelting  

DOE Patents [OSTI]

The invention relates to improved apparatuses and methods for remelting metal alloys in furnaces, particularly consumable electrode vacuum arc furnaces. Excited reactive gas is injected into a stationary furnace arc zone, thus accelerating the reduction reactions which purify the metal being melted. Additionally, a cooled condensation surface is disposed within the furnace to reduce the partial pressure of water in the furnace, which also fosters the reduction reactions which result in a purer produced ingot. Methods and means are provided for maintaining the stationary arc zone, thereby reducing the opportunity for contaminants evaporated from the arc zone to be reintroduced into the produced ingot.

Zanner, Frank J. (Sandia Park, NM); Williamson, Rodney L. (Albuquerque, NM); Smith, Mark F. (Albuquerque, NM)

1994-12-13T23:59:59.000Z

26

Hydrogen-induced cracking along the fusion boundary of dissimilar metal welds  

SciTech Connect (OSTI)

Presented here are the results from a series of experiments in which dissimilar metals welds were made using the gas tungsten arc welding process with pure argon or argon-6% hydrogen shielding gas. The objective was to determine if cracking near the fusion boundary of dissimilar metal welds could be caused by hydrogen absorbed during welding and to characterize the microstructures in which cracking occurred. Welds consisted of ER308 and ER309LSi austenitic stainless steel and ERNiCr-3-nickel-based filler metals deposited on A36 steel base metal. Cracking was observed in welds made with all three filler metals. A ferrofluid color metallography technique revealed that cracking was confined to regions in the weld metal containing martensite. Microhardness indentations indicated that martensitic regions in which cracking occurred had hardness values from 400 to 550 HV. Cracks did not extend into bulk weld metal with hardness less than 350 HV. Martensite formed near the fusion boundary in all three filler metals due to regions of locally increased base metal dilution.

Rowe, M.D.; Nelson, T.W.; Lippold, J.C. [Ohio State Univ., Columbus, OH (United States)

1999-02-01T23:59:59.000Z

27

Dilution and microsegregation in dissimilar metal welds between super austenitic  

E-Print Network [OSTI]

Dilution and microsegregation in dissimilar metal welds between super austenitic stainless steel the weld will also signi® cantly affect the corrosion resistance. Dissimilar metal welds between a super dissimilar weld. The dilution level was found to decrease as the ratio of volumetric ® ller metal feedrate

DuPont, John N.

28

Increasing Productivity of Welding  

E-Print Network [OSTI]

trend toward the continuous electrode wire pro e s cesses and away from shielded metal-arc welding dr stick welding as it is commonly called. The con tinuous electrode wire process include gas metal arc welding "GMAW", f lux-cored arc welding... versus the s shielded becomes more complex. However, for hi er strength materials, the gas shielded version is preferred, primarily because it can be used to the low alloy, high strength steels and will pr deposited weld metal closely approaching...

Uhrig, J. J.

1983-01-01T23:59:59.000Z

29

WeldingFabr&MetalForm  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Welding, Welding, Fabrication, and Metal Forming Manufacturing Technologies The department consists of three trades: weld- ing; fabrication and assembly; and precision metal forming. These interrelated groups use similar equipment and rely on each other's skills. One stop will get you the service of three reliable trades. The team manufactures and assembles proto- type hardware and has the in-house capability of producing hardware with sizes ranging from thumbnail to rail-car. Expertise includes aircraft quality sheet metal construction, certified weld- ing, and assembly. The staff has experience managing a variety of activities: design modifi- cation assistance; in-house fabrication; and project management and can work with your engineers to transform sketches and ideas into working prototypes.

30

WELDING RESEARCH -s77WELDING JOURNAL  

E-Print Network [OSTI]

to the changing microstructure from base metal to the weld zone, there are corresponding changes in hardness been performed on similar and dissimilar welds of aluminum alloys of the 1xxx, 2xxx, 5xxx, 6xxx, and 7- genic gas generated in arc welding by evaporation from the liquid pool and molten metal droplets (in

DuPont, John N.

31

A comparative evaluation of low-cycle fatigue behavior of type 316LN base metal, 316 weld metal, and 316LN/316 weld joint  

SciTech Connect (OSTI)

A comparative evaluation of the low-cycle fatigue (LCF) behavior of type 316LN base metal, carried out at 773 and 873 K. Total strain-controlled LCF tests were conducted at a constant strain rate of 3 {times} 10{sup {minus}3} s{sup {minus}1} with strain amplitudes in the range {+-}0.20 to {+-}1.0 pct. Weld pads with single V and double V configuration were prepared by the shielded metal-arc welding (SMAW) process using 316 electrodes for weld-metal and weld-joint specimens. Optical microscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) of the untested and tested samples were carried out to elucidate the deformation and the fracture behavior. The cyclic stress response of the base metal shows a very rapid hardening to a maximum stress followed by a saturated stress response. Weld metal undergoes a relatively short initial hardening followed by a gradual softening regime. Weld joints exhibit an initial hardening and a subsequent softening regime at all strain amplitudes, except at low strain amplitudes where a saturation regime is noticed. The initial hardening observed in base metal has been attributed to interaction between dislocations and solute atoms/complexes and cyclic saturation to saturation in the number density of slip bands. The 18-8 group of austenitic stainless steels, such as AISI type 316, 304, and their modified grades, finds applications as structural material for various components of the liquid-metal-cooled fast breeder reactor (LMFBR).

Valsan, M.; Sundararaman, D.; Sankara Rao, K.B.; Mannan, S.L. [Indira Gandhi Centre for Atomic Research, Tamil Nadu (India)

1995-05-01T23:59:59.000Z

32

E-Print Network 3.0 - arc welding robot Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

robot Search Powered by Explorit Topic List Advanced Search Sample search results for: arc welding robot Page: << < 1 2 3 4 5 > >> 1 ORIGINAL ARTICLE Development of a mobile...

33

Laser Welding of Metals [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Welding of Metals Laser Welding of Metals Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Welding of Metals Project description: High-speed laser welding of metals. Category: Project with industrial partner (Delphi Energy and Engine Management Systems) Bookmark and Share

34

Simple test for dissimilar-metal welds  

SciTech Connect (OSTI)

A simplified accelerated test procedure has been developed for testing dissimilar-metal welds between austenitic stainless steels and low-alloy ferritic steels. The failure of these welded joints in operating steam generators of fossil-fired power plants has become an increasing problem for the utility industry. The proposed test is a three-point loading, bent-beam test that uses sheet specimens taken from a dissimilar-metal weldment. Tests were conducted in a simple test fixture where the specimens are loaded with a set-screw. To determine whether the test produces the same type of failure as those produced in a power plant, tests were conducted on specimens taken from a weld between Type 316 stainless steel and 2 1/4 Cr-1 Mo steel plates using Type 309 stainless steel filler metal. The specimens were loaded in the test fixture at room temperature and then thermally cycled between room temperature and 593/sup 0/C (1099/sup 0/F) by placing the test apparatus in a box furnace (thermal cycling during power plant operation plays a major role in the weld failure during service). The specimens were kept in the furnace for 20 to 70 hours (h), cooled to room temperature, and then the cycle was repeated. Metallographic examination of specimens cycled as few as 64 times with a total of 2300 h at 593/sup 0/C revealed that the specimens contained cracks similar to the cracks observed on dissimilar-metal welds cut from steam tubes after long-time elevated-temperature service racks similar to the cracks observed on dissimilar-metal welds cut from steam tubes after longtime elevated-temperature service in a fossil-fired steam generator. All indications are that this simple accelerated test could be used as a screening procedure to compare the relative behavior of ''improved'' welds in future research and development programs.

Klueh, R.L.; King, J.F.; Griffith, J.L.

1983-06-01T23:59:59.000Z

35

Convection in Arc Weld Pools Electromagnetic and surface tension forces are shown to  

E-Print Network [OSTI]

Convection in Arc Weld Pools Electromagnetic and surface tension forces are shown to dominate flow tension forces. It is shown that the electromag- netic and surface tension forces domi- nate the flow by experimental measurements of segrega- tion in the weld pool. It is also shown that the surface tension driven

Eagar, Thomas W.

36

WELDING RESEARCH OCTOBER 2005-s156  

E-Print Network [OSTI]

of the welding fume reveals that gas metal arc welding (GMAW) fume consists pre- dominately of particle of the chemicals present in the in- haled particles. Particles or agglomerates between 0.1 and 1 µm can be exhaled with different size range capabilities to measure the particle size of gas metal arc welding (GMAW) fume

Eagar, Thomas W.

37

Examination of dissimilar metal welds in BWR and PWR piping  

SciTech Connect (OSTI)

This paper addresses dissimilar metal weld examinations at PWRS. Surveys were conducted to document the dissimilar metal weld configurations at PWR plants and to update the information known about dissimilar metal weld configurations at BWR plants. The experiences which BWR utilities have had with dissimilar metal weld examinations are documented and include: correct identification of IGSCC, indications thought to be IGSCC but were actually fabrication flaws, and difficulties encountered with the examination of dissimilar metal welds after stress improvement. An experimental program was conducted which verified that the longitudinal wave procedures developed for BWRs are also applicable to PWR designs.

MacDonald, D.E. [Electric Power Research Inst., Charlotte, NC (United States). NDE Center

1994-12-31T23:59:59.000Z

38

Carbide Precipitation in Steel Weld Metals  

E-Print Network [OSTI]

Carbide Precipitation in Steel Weld Metals www.msm.cam.ac.uk/phase-trans #12 diffusion into austenite Carbon diffusion into austenite and carbide precipitation in ferrite Carbide precipitation from austenite CASE 2: elimination of carbides #12;#12;#12;0.110.090.070.050.03 0.2 0.4 0.6 0.8 1

Cambridge, University of

39

New findings in welding of structural steels  

Science Journals Connector (OSTI)

Gas shielded arc welding is the most widely applied welding process in industry. H2 (1.0425) structural steel chosen can be welded very cost-effectively with VAC 60 welding wires in CO2 shielding gas. With only the replacement of a highly oxidising gas, i.e. CO2, with a less oxidising gas mixture, i.e. Ar+18% CO2, a nicer appearance of the weld face and a higher weld quality may be obtained. Still higher quality of welds may be accomplished by employing pulsed arc welding of structural steels. In the study and development of the existing welding process, special attention was paid to the metal transfer. In pulsed arc welding with VAC 60 wire in the protective gas mixture of Ar+18% CO2, the metal transfer is very smooth and uniform in a very wide range of welding parameters. Because of the low oxidising capability of the Ar+18% CO2 gas mixture and the very short time of droplet formation, however, in pulsed arc welding major chemical processes in the droplet will occur only in welding with a higher average welding current (281 A). Less alloyed surfacing welds with silicon and manganese will provide higher quality only because of the surfacing weld dilution resulting from the parent-metal fusion, i.e. penetration. In pulsed arc welding, a pulse shape and energy and base current may efficiently affect the degree of penetration.

Uros Kejzar; Rajko Kejzar; Janez Grum; Damjan Klobcar

2007-01-01T23:59:59.000Z

40

Laser-ultrasonic inspection of hybrid laser-arc welded HSLA-65 steel  

SciTech Connect (OSTI)

The hybrid laser-arc welding (HLAW) process is a relatively low heat input joining technology that combines the synergistic qualities of both the high energy density laser beam for deep penetration and the arc for wide fit-up gap tolerance. This process is especially suitable for the shipbuilding industry where thick-gauge section, long steel plates have been widely used in a butt joint configuration. In this study, preliminary exploration was carried out to detect and visualize the welding defects using laser ultrasonics combined with the synthetic aperture focusing technique (SAFT). Results obtained on 9.3 mm thick butt-welded HSLA-65 steel plates indicated that the laser-ultrasonic SAFT inspection technique can successfully detect and visualize the presence of porosity, lack of fusion and internal crack defects. This was further confirmed by X-ray digital radiography and metallography. The results obtained clearly show the potential of using the laser-ultrasonic technology for the automated inspection of hybrid laser-arc welds.

Lévesque, D.; Rousseau, G.; Monchalin, J.-P. [National Research Council Canada, Boucherville, QC (Canada); Wanjara, P.; Cao, X. [National Research Council Canada, Montreal, QC (Canada)

2014-02-18T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Localized weld metal corrosion in stainless steel water tanks  

SciTech Connect (OSTI)

The rapidly developed leaks within the TFC and TFD tanks (LLNL groundwater treatment facilities) were caused by localized corrosion within the resolidified weld metal. The corrosion was initiated by the severe oxidation of the backsides of the welds which left the exposed surfaces in a condition highly susceptible to aqueous corrosion. The propagation of surface corrosion through the thickness of the welds occurred by localized corrosive attack. This localized attack was promoted by the presence of shielded aqueous environments provided by crevices at the root of the partial penetration welds. In addition to rapid corrosion of oxidized surfaces, calcium carbonate precipitation provided an additional source of physical shielding from the bulk tank environment. Qualification testing of alternate weld procedures showed that corrosion damage can be prevented in 304L stainless steel GTA welds by welding from both sides while preventing oxidation of the tank interior through the use of an inert backing gas such as argon. Corrosion resistance was also satisfactory in GMA welds in which oxidized surfaces were postweld cleaned by wire brushing and chemically passivated in nitric acid. Further improvements in corrosion resistance are expected from a Mo-containing grade of stainless steel such as type 316L, although test results were similar for type 304L sheet welded with type 308L filler metal and type 316L sheet welded with type 316L filler metal.

Strum, M.J.

1995-05-25T23:59:59.000Z

42

Video Game Device Haptic Interface for Robotic Arc Welding  

SciTech Connect (OSTI)

Recent advances in technology for video games have made a broad array of haptic feedback devices available at low cost. This paper presents a bi-manual haptic system to enable an operator to weld remotely using the a commercially available haptic feedback video game device for the user interface. The system showed good performance in initial tests, demonstrating the utility of low cost input devices for remote haptic operations.

Corrie I. Nichol; Milos Manic

2009-05-01T23:59:59.000Z

43

Influence of Aluminum Content on Grain Refinement and Strength of AZ31 Magnesium GTA Weld Metal  

SciTech Connect (OSTI)

The goal is to characterize the effect of Al content on AZ31 weld metal, the grain size and strength, and examine role of Al on grain refinement. The approach is to systematically vary the aluminum content of AZ31 weld metal, Measure average grain size in weld metal, and Measure cross-weld tensile properties and hardness. Conclusions are that: (1) increased Al content in AZ31 weld metal results in grain refinement Reason: higher undercooling during solidification; (2) weld metal grain refinement resulted in increased strength & hardness Reason: grain boundary strengthening; and (3) weld metal strength can be raised to wrought base metal levels.

Babu, N. Kishore [Singapore Institute of Manufacturing Technology; Cross, Carl E. [Los Alamos National Laboratory

2012-06-28T23:59:59.000Z

44

Dissimilar-metal weld failures in boiler tubing  

SciTech Connect (OSTI)

Both ferritic heat-resisting steels and austenitic stainless steels are used for fossil-fired boilers for central power stations. The use of these two different types of materials within the system leads to the need for a dissimilar-metal weld transition joint. Increased cyclic operation of boilers has led to a rash of failures in welds between dissimilar metals; studies have identified the causes, and improved nondestructive testing techniques permit early identification of problem areas.

Klueh, R.L.

1984-02-01T23:59:59.000Z

45

Method for welding beryllium  

DOE Patents [OSTI]

A method is provided for joining beryllium pieces which comprises: depositing aluminum alloy on at least one beryllium surface; contacting that beryllium surface with at least one other beryllium surface; and welding the aluminum alloy coated beryllium surfaces together. The aluminum alloy may be deposited on the beryllium using gas metal arc welding. The aluminum alloy coated beryllium surfaces may be subjected to elevated temperatures and pressures to reduce porosity before welding the pieces together. The aluminum alloy coated beryllium surfaces may be machined into a desired welding joint configuration before welding. The beryllium may be an alloy of beryllium or a beryllium compound. The aluminum alloy may comprise aluminum and silicon.

Dixon, Raymond D. (Los Alamos, NM); Smith, Frank M. (Espanola, NM); O'Leary, Richard F. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

46

Carbon migration in 5Cr-0.5Mo/21Cr-12Ni dissimilar metal welds  

SciTech Connect (OSTI)

The carbon migration between a ferritic steel and an austenitic steel was studied in submerged arc-welded 5Cr-0.5Mo/21Cr-12Ni dissimilar metal welds (DMWs) after aging at 500 C for various times and after long-term service in technical practice. The distribution of carbon, chromium, nickel, and iron in the areas around the weld interface was determined by electron probe microanalysis, and the microstructural aspect in the carbon-depleted/enriched zone was characterized by optical microscopy and transmission electron microscopy (TEM). Furthermore, the precipitation sequences and composition characteristics of the carbides were identified by diffraction pattern microanalysis and energy-dispersive X-ray (EDX) microanalysis. It was found (1) that there exists a coherent relationship between intracrystalline M{sub 23}C{sub 6} and the austenitic matrix; (2) that the composition of M{sub 23}C{sub 6} in the carbon-enriched zone is independent of the duration of aging and service; (3) that the maximum carbon concentration is determined by the carbide type, the composition characteristic of precipitated carbides, and the concentration of carbide-forming Cr adjacent to the weld interface in the carbon-enriched zone; and (4) that the carbon migration in the 5Cr-0.5Mo/21Cr-12Ni DMWs can be described by a diffusion model.

Huang, M.L.; Wang, L. [Dalian Univ. of Technology (China). Dept. of Materials Engineering

1998-12-01T23:59:59.000Z

47

Microstructural study of high energy density dissimilar metal welds  

SciTech Connect (OSTI)

Electron microscopy analysis of two different CO/sub 2/ laser welded dissimilar metal combinations revealed the presence of minor constituents which could be attributed to terminal solidification events. In the case of the 15-5 PH/HP 9-4-20 welds, a NbC/austenite eutectic-type constituent was identified, which accounted for the observed fusion-zone hot cracks in these welds. The identity of the interdendritic constituent first observed optically by Patterson and Milewski/sup 9/ in 304L/625 GTA welds has been confirmed as Laves phase. It was further determined that this phase is enriched in Mo and Nb relative to the austenite matrix.

Cieslak, M.J.; Hills, C.R.; Headley, T.J.

1986-01-01T23:59:59.000Z

48

Effects of alloying elements on the strength and cooling rate sensitivity of ultra-low carbon alloy steel weld metals. Technical report  

SciTech Connect (OSTI)

A study was conducted to evaluate the effect of weld cooling rate on the strength of autogenous GTAW deposited weld metal. The basic weld metal composition was based on a low carbon bainite metallurgical system. The weld metal yield strength goal was 130 ksi, needed to surpass the current HY-13O weld metal requirements. Vacuum Induction Melted (VIM) heats of steel were produced and processed into 3/4` thickness plates. The autogenous gas tungsten arc welds (GTAW) on the parent steel plates were produced under two different heat input conditions. Tensile specimens were produced from the weldments; specimens from certain heats were subjected to gleeble thermal simulations of multi-pass welding conditions using the Gleeble 1500. All specimens were then evaluated for yield and ultimate tensile strength. From the data presented, it was found that the experimental compositions studied were less sensitive to cooling rate than current HY-130 welding consumables. The compositions tested approached the target yield strength of 130 ksi, but further work is necessary in this area.

Vassilaros, M.G.

1994-03-01T23:59:59.000Z

49

Development of a Plasma Arc Manufacturing Process and Machine to Create Metal Oxide Particles in Water From Wire Feedstock.  

E-Print Network [OSTI]

??A plasma arc erosion process can be used to create metal and metal oxide particles in the ultra-fine size range (<70 um). An electric arc… (more)

George, Jonathan Alan 1983-

2010-01-01T23:59:59.000Z

50

Set up an Arc Welding Code with Enthalpy Method in Upwind Scheme  

SciTech Connect (OSTI)

In this study, a numerical code with enthalpy method in upwind scheme is proposed to estimate the distribution of thermal stress in the molten pool, which is primarily determined by the type of the input power and travel speed of heating source. To predict the cracker deficit inside the workpiece, a simulated program satisfying the diagonal domination and Scarborough criterion provides a stable iteration. Meantime, an experimental performance, operated by robot arm 'DR-400' to provide a steady and continuous arc welding, was also conducted to verify the simulated result. By surveying the consistence of molten pool bounded by contrast shade and simulated melting contour on the surface of workpiece, the validity of model proposed to predict the thermal cracker has been successfully identified.

Ho, J.-E. [Department of Mechanical Engineering, National Ilan University, Ilan, Taiwan (China)

2010-05-21T23:59:59.000Z

51

Electron beam welding of ceramic to metal using fore-vacuum plasma electron source  

Science Journals Connector (OSTI)

The possibility of creating ceramic-metal joints by electron beam welding is considered. The welding of ... range (5–20 Pa) using a plasma electron source. The structure and composition of the ceramic ... breakin...

A. K. Goreev; V. A. Burdovitsin; A. S. Klimov…

2012-09-01T23:59:59.000Z

52

E-Print Network 3.0 - alloy welded joints Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

arc welding is a unique arc welding process for deep Summary: welding (GTAW) in terms of penetration depth, joint preparation and thermal distortion (Ref. 2). Although... welding...

53

3612--VOLUME 27A, NOVEMBER 1996 METALLURGICAL AND MATERIALS TRANSACTIONS A Solidification of an Alloy 625 Weld Overlay  

E-Print Network [OSTI]

steel by gas metal arc welding was investigated by light and electron optical microscopy, electron to that produced in dissimilar welds between Alloy 625 and Cr- Mo steels in weld overlay applications of an Alloy 625 Weld Overlay J.N. DuPONT The solidification behavior (microsegregation, secondary phase

DuPont, John N.

54

Friction welded nonconsumable electrode assembly and use thereof for electrolytic production of metals and silicon  

DOE Patents [OSTI]

A nonconsumable electrode assembly suitable for use in the production of metal by electrolytic reduction of a metal compound dissolved in a molten salt, the assembly comprising a metal conductor and a ceramic electrode body connected by a friction weld between a portion of the body having a level of free metal or metal alloy sufficient to effect such a friction weld and a portion of the metal conductor.

Byrne, Stephen C. (Monroeville, PA); Ray, Siba P. (Pittsburgh, PA); Rapp, Robert A. (Columbus, OH)

1984-01-01T23:59:59.000Z

55

Spatial and time-dependent distribution of plasma parameters in the metal-halide arc lamp.  

E-Print Network [OSTI]

Spatial and time-dependent distribution of plasma parameters in the metal-halide arc lamp. A. Khakhaev, L. Luizova, K. Ekimov and A. Soloviev Petrozavodsk State University, Russia The metal-halide arc lamp is an effective light source and its investigation has a long history, but even at present some

Paris-Sud XI, Université de

56

E-Print Network 3.0 - arc weld-surfacing process Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Electrical and Computer Engineering, University of Kentucky Collection: Engineering 3 GIS by ESRITM What is ArcGIS Summary: PlotTM, ArcEditTM, and so on). Geo- processing Map...

57

Towards Real Time Diagnostics of Hybrid Welding Laser/GMAW  

SciTech Connect (OSTI)

Methods are currently being developed towards a more robust system real time feedback in the high throughput process combining laser welding with gas metal arc welding. A combination of ultrasonic, eddy current, electronic monitoring, and visual techniques are being applied to the welding process. Initial simulation and bench top evaluation of proposed real time techniques on weld samples are presented along with the concepts to apply the techniques concurrently to the weld process. Consideration for the eventual code acceptance of the methods and system are also being researched as a component of this project. The goal is to detect defects or precursors to defects and correct when possible during the weld process.

Timothy Mcjunkin; Dennis C. Kunerth; Corrie Nichol; Evgueni Todorov; Steve Levesque; Feng Yu; Robert Danna Couch

2013-07-01T23:59:59.000Z

58

Ultrasonic Evaluation of Two Dissimilar Metal Weld Overlay Specimens  

SciTech Connect (OSTI)

Two dissimilar metal weld (DMW) pipe-to-nozzle specimens were implanted with thermal fatigue cracks in the 13% to 90% through-wall depth range. The specimens were ultrasonically evaluated with phased-array probes having center frequencies of 0.8, 1.0, 1.5, and 2.0 megahertz (MHz). An Alloy 82/182 weld overlay (WOL) was applied and the specimens were ultrasonically re-evaluated for flaw detection and characterization. The Post-WOL flaw depths were approximately 10% to 56% through-wall. This study has shown the effectiveness of ultrasonic examinations of Alloy 82/182 overlaid DMW specimens. Phased-array probes with center frequency in the 0.8- to 1.0-MHz range provide a strong coherent signal but the greater ultrasonic wavelength and larger beam spot size prevent the reliable detection of small flaws. These small flaws had nominal through-wall depths of less than 15% and length in the 50-60 mm (2-2.4 in.) range. Flaws in the 19% and greater through-wall depth range were readily detected with all four probes. At the higher frequencies, the reflected signals are less coherent but still provide adequate signal for flaw detection and characterization. A single inspection at 2.0 MHz could provide adequate detection and sizing information but a supplemental inspection at 1.0 or 1.5 MHz is recommended.

Crawford, Susan L.; Cinson, Anthony D.; Prowant, Matthew S.; Moran, Traci L.; Anderson, Michael T.

2012-06-30T23:59:59.000Z

59

Influence of Alloy and Solidification Parameters on Grain Refinement in Aluminum Weld Metal due to Inoculation  

SciTech Connect (OSTI)

The goals are: (1) Establish how much Ti/B grain refiner is need to completely refine aluminum weld metal for different alloys and different welding conditions; (2) Characterize how alloy composition and solidification parameters affect weld metal grain refinement; and (3) Apply relevant theory to understand observed behavior. Conclusions are: (1) additions of Ti/B grain refiner to weld metal in Alloys 1050, 5083, and 6082 resulted in significant grain refinement; (2) grain refinement was more effective in GTAW than LBW, resulting in finer grains at lower Ti content - reason is limited time available for equiaxed grain growth in LBW (inability to occlude columnar grain growth); (3) welding travel speed did not markedly affect grain size within GTAW and LBW clusters; and (4) application of Hunt CET analysis showed experimental G to be on the order of the critical G{sub CET}; G{sub CET} was consistently higher for GTAW than for LBW.

Schempp, Philipp [BAM, Germany; Tang, Z. [BIAS, Germany; Cross, Carl E. [Los Alamos National Laboratory; Seefeld, T. [BIAS, Germany; Pittner, A. [BAM, Germany; Rethmeier, M. [BAM, Germany

2012-06-28T23:59:59.000Z

60

Analysis of effect of temperature gradients on surface-tension phenomena in gas-tungsten-arc welds  

SciTech Connect (OSTI)

Fluid motion directed by surface tension is considered as a contributor to heat penetration in a weld pool. The potential phenomena at the gas-liquid interface were analyzed, and the dependence of surface motion on temperature in the gas-tungsten-arc (GTA) welding process was examined. An existing heat-transfer model was used and was able to predict weld size to +- 50% of the actual value. A momentum-transfer equation was derived by considering the contribution of Lorentz force. The momentum boundary condition was developed and was able to predict the Marangoni effect. The magnitude of surface-tension-driven force is comparable to the gravitational force on one gram. An empirical approach was proposed to couple heat-transfer and momentum-transfer phenomena. A dimensional analysis identified the pertinent dimensionless groups as Reynolds, Weber, Froude, Peclet, and Power numbers and a dimensionless velocity. A simplified form of the correction was developed by combining dimensionless groups to yield a correlation with the Bond, Prandtl, and modified power numbers. Future experimental work was proposed to test the functionality of the dimensionless groups.

Lee, H.A.; Chien, P.S.J.

1982-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Characterization of Defocused Electron Beams and Welds in Stainless Steel and Refractory Metals using the Enhanced Modified Faraday Cup Diagnostic  

SciTech Connect (OSTI)

As the first part of a project to compare new generation, continuous wave, laser welding technology to traditional electron beam welding technology, electron beam welds were made on commercially pure vanadium refractory metal and 21-6-9 austenitic stainless steel. The electron beam welds were made while employing EB diagnostics to fully characterize the beams so that direct comparisons could be made between electron beam and laser beams and the welds that each process produces.

Elmer, J W

2009-01-23T23:59:59.000Z

62

High power x-ray welding of metal-matrix composites  

DOE Patents [OSTI]

A method for joining metal-matrix composites (MMCs) by using high power x-rays as a volumetric heat source is provided. The method involves directing an x-ray to the weld line between two adjacent MMCs materials to create an irradiated region or melt zone. The x-rays have a power density greater than about 10.sup.4 watts/cm.sup.2 and provide the volumetric heat required to join the MMC materials. Importantly, the reinforcing material of the metal-matrix composites remains uniformly distributed in the melt zone, and the strength of the MMCs are not diminished. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys. In an alternate embodiment, high power x-rays are used to provide the volumetric heat required to weld metal elements, including metal elements comprised of metal alloys.

Rosenberg, Richard A. (Naperville, IL); Goeppner, George A. (Orland Park, IL); Noonan, John R. (Naperville, IL); Farrell, William J. (Flossmoor, IL); Ma, Qing (Westmont, IL)

1999-01-01T23:59:59.000Z

63

The problems of weld metal or heat affected zone toughness in offshore structural steels  

SciTech Connect (OSTI)

An extensive set of fracture toughness results for welded offshore structural steels, gathered from nine separate sponsoring companies, has been entered into a specially constructed database. With over eleven thousand Charpy results and over two thousand CTOD results available, it has been possible to analyze the occurrence of low toughness results with respect to variables such as thickness, PWHT, steel production route etc., even though the individual test programs were not specifically structured to do this. This paper concentrates on the toughness of the weld metal. The data demonstrates that the likelihood of a low toughness result from a CTOD test in weld metal at {minus}10 C is comparable with that from the HAZ region for welded offshore structural steels, and PWHT of the joint is beneficial in reducing the occurrence of low toughness values in the weld metal. It is therefore important that when the HAZ performance is assessed, either through weld procedure tests or plate prequalification procedures, adequate attention is also paid to the weld metal toughness.

Hancock, P.; Spurrier, J.; Chubb, J.P. [Cranfield Univ. (United Kingdom). School of Industrial and Manufacturing Science

1996-12-01T23:59:59.000Z

64

Fatique Resistant, Energy Efficient Welding Program, Final Technical Report  

SciTech Connect (OSTI)

The program scope was to affect the heat input and the resultant weld bead geometry by synchronizing robotic weave cycles with desired pulsed waveform shapes to develop process parameters relationships and optimized pulsed gas metal arc welding processes for welding fatique-critical structures of steel, high strength steel, and aluminum. Quality would be addressed by developing intelligent methods of weld measurement that accurately predict weld bead geometry from process information. This program was severely underfunded, and eventually terminated. The scope was redirected to investigate tandem narrow groove welding of steel butt joints during the one year of partial funding. A torch was designed and configured to perform a design of experiments of steel butt weld joints that validated the feasability of the process. An initial cost model estimated a 60% cost savings over conventional groove welding by eliminating the joint preparation and reducing the weld volume needed.

Egland, Keith; Ludewig, Howard

2006-05-25T23:59:59.000Z

65

Oxygen and Nitroaen Contamination During Submerged Arc Wel ding of Titanium  

E-Print Network [OSTI]

) ) ) ··- -~ Oxygen and Nitroaen Contamination During Submerged Arc Wel ding of Titanium T· \\v· Eagar* The oxygen content of ti tanium submerged arc wel ~ metal is primaril y derendent uron the purity of the fluo1~ ide fluxes, but it is shown here that the oxygen content of the weld metal may be affected

Eagar, Thomas W.

66

Pressure Resistance Welding of High Temperature Metallic Materials  

SciTech Connect (OSTI)

Engineers from the Idaho National Laboratory (INL) have demonstrated an innovative method for seal or pinch welding stainless steel tubing. Sometimes a tube has fuel or contamination that must be contained, or the tube needs to be shortened or cut for handling, and the tube needs to have a guaranteed sealed weld that is both quick and easy. This technique was demonstrated in a laboratory using a resistance welding system with specially designed electrodes to ensure a tube end is seal welded or if a long tube is to be shortened, the severed ends are seal welded. The unique electrodes design is integral to achieving the sealed ends. This process could readily be adapted for robotic--remote handling or for contact handling in a glovebox or hood.

Larry Zirker; Craig Tyler

2010-08-01T23:59:59.000Z

67

Refractory metal welding using a 3.3 kW diode pumped Nd:YAG laser.  

SciTech Connect (OSTI)

Recent developments in multi-kilowatt continuous wave lasers allow fiber optic delivery to high-purity controlled atmosphere chambers and challenge electron beam welding with improvements in cost, complexity, beam quality and flexibility. Questions remain with respect to the performance of these lasers for refractory alloy welding regarding damaging back reflections, laser-plume interactions, and sufficiency of beam intensity and coupled energy. System performance for the welding of various refractory metal alloys and comparisons to electron beam welds will be presented.

Carpenter, R. W. (Robert W.); Piltch, M. S. (Martin S.); Nemec, R. B. (Ronald B.); Milewski, J. O. (John O.)

2001-01-01T23:59:59.000Z

68

WELDING RESEARCH -s55WELDING JOURNAL  

E-Print Network [OSTI]

WELDING RESEARCH -s55WELDING JOURNAL ABSTRACT. Dissimilar metal weld (DMW) failures between carbon corrosion conditions that require the use of austenitic stainless steels. A dissimi- lar metal weld (DMW to understand the mechanism of DMW failures in such applications. In the as-welded condition, a compo- sition

DuPont, John N.

69

WELDING RESEARCH -S125WELDING JOURNAL  

E-Print Network [OSTI]

cracking susceptibility of dissimilar metal welds between AL- 6XN super austenitic stainless steel and two and independent of weld metal dilution level, while the cracking suscepti- bility of welds produced with IN625 resistance of the weld metal. Previous research has shown that the depleted dendrite cores are susceptible

DuPont, John N.

70

The effect of iron dilution on strength of nickel/steel and Monel/steel welds  

SciTech Connect (OSTI)

The weld strength, as a function of iron content, for nickel/steel and Monel/steel welds was determined. Samples were prepared using a Gas Metal Arc (GMAW) automatic process to weld steel plate together with nickel or Monel to produce a range of iron contents typical of weld compositions. Tensile specimens of each iron content were tested to obtain strength and ductility measurements for that weld composition. Data indicate that at iron contents of less than 20% iron in a nickel/steel weld, the weld fails at the weld interface, due to a lack of fusion. Between 20% and 35% iron, the highest iron dilution that could be achieved in a nickel weld, the welds were stronger than the steel base metal. This indicates that a minimum amount of iron dilution (20%) is necessary for good fusion and optimum strength. On the other hand for Monel/steel welds, test results showed that the welds had good strength and integrity between 10% and 27% iron in the weld. Above 35% iron, the welds have less strength and are more brittle. The 35% iron content also corresponds to the iron dilution in Monel welds that has been shown to produce an increase in corrosion rate. This indicates that the iron dilution in Monel welds should be kept below 35% iron to maximize both the strength and corrosion resistance. 2 refs., 6 figs., 3 tabs.

Fout, S.L.; Wamsley, S.D.

1983-03-28T23:59:59.000Z

71

Stress Corrosion Cracking and Non-Destructive Examination of Dissimilar Metal Welds and Alloy 600  

SciTech Connect (OSTI)

The United States Nuclear Regulatory Commission (USNRC) has conducted research since 1977 in the areas of environmentally assisted cracking and assessment and reliability of non-destructive examination (NDE). Recent occurrences of cracking in Alloy 82/182 welds and Alloy 600 base metal at several domestic and overseas plants have raised several issues relating to both of these areas of NRC research. The occurrences of cracking were identified by the discovery of boric acid deposits resulting from through-wall cracking in the primary system pressure boundary. Analyses indicate that the cracking has occurred due to primary water stress corrosion cracking (PWSCC) in Alloy 82/182 welds. This cracking has occurred in two different locations: in hot leg nozzle-to-safe end welds and in control rod drive mechanism (CRDM) nozzle welds. The cracking associated with safe-end welds is important due to the potential for a large loss of reactor coolant inventory, and the cracking of CRDM nozzle base metal and welds, particularly circumferential cracking of CRDM nozzle base metal, is important due to the potential for a control rod to eject resulting in a loss of coolant accident. The industry response in the U.S. to this cracking is being coordinated through the Electric Power Research Institute's Materials Reliability Project (EPRI-MRP) in a comprehensive, multifaceted effort. Although the industry program is addressing many of the issues raised by these cracking occurrences, confirmatory research is necessary for the staff to evaluate the work conducted by industry groups. Several issues requiring additional consideration regarding the generic implications of these isolated events have been identified. This paper will discuss the recent events of significant cracking in domestic and foreign plants, discuss the limitations of NDE in detecting SCC, identify deficiencies in information available in this area, discuss the USNRC approach to address these issues, and discuss the development of an international cooperative effort. (authors)

Jackson, Deborah A. [U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001 (United States)

2002-07-01T23:59:59.000Z

72

Heat and Metal Transfer in Gas Metal Arc Welding Using Argon and Helium  

E-Print Network [OSTI]

. Massachusetts Institute of Tc:chnology, is Head of Secondary Metallurgy Group with MEFOS. Lulea, Sweden. T

Eagar, Thomas W.

73

WELDING RESEARCH -s51WELDING JOURNAL  

E-Print Network [OSTI]

mixed zone (PMZ) of dissimilar welds. Introduction Ferritic-to-austenitic dissimilar metal welds). Nickel-based filler metals are often used to prolong the life of austenitic-to- ferritic dissimilar welds to examine the gradient of alloying elements across the weld inter- face of austenitic/ferritic dissimilar

DuPont, John N.

74

Assessment of Hydrogen Cracking Risk in Multipass Weld Metal of 2.25Cr-1Mo-0.25V-TiB (T24) Boiler Steel  

Science Journals Connector (OSTI)

Welding modern high-strength steel with low carbon and impurity contents, preheating may be dictated by cracking sensitivity of the weld metal instead of the HAZ. Standardised methods are mostly developed for ...

P. Nevasmaa; A. Laukkanen

2005-07-01T23:59:59.000Z

75

Materials Reliability Program Low-Temperature Cracking of Nickel-Based Alloys and Weld Metals (MRP-108)  

SciTech Connect (OSTI)

OAK-B135 A rising load test in low-temperature (50-100 degree C) pH 10 water containing a high concentration of dissolved hydrogen (150 cc/kg) has demonstrated that Alloy 690 as well as weld metals 82 and 52 exhibit a marked loss of ductility. A similar loss of ductility has been shown to occur in widely used weld metal 182 under replica test conditions and simulated PWR primary water containing 100 cc/kg of hydrogen. The objective of this report was to confirm the Bettis test results for weld metal 82 and determine whether weld metal 182 is susceptible to the same reductions in toughness. This report documents the first industry effort to reckon with the low temperature crack propagation (LTCP) issue.

B. Young

2004-02-01T23:59:59.000Z

76

Effect of pressure and shielding gas on the microstructure of hyperbaric metal cored GMAW welds down to 111 bar  

SciTech Connect (OSTI)

The microstructural evolution of hyperbaric C-Mn weld metals was studied by means of bead-on-plate welds deposit with GMAW process using a commercial metal cored wire. The welding was carried out in the flat position in the range of 51 bar to 111 bar with He+ CO{sub 2} as shielding gas, which CO{sub 2} content varied from 0.1% to 0.8 %. The microstructures were quantitatively analyzed by optical microscopy to evaluate the amount of constituents according to the IIW/IIS terminology. The results showed that all weld metals presented great amounts of acicular ferrite and a stronger influence of pressure on microstructure compared to the influence of the shielding gas.

Jorge, J.C.F. [CEFET, Rio de Janeiro (Brazil). Mechanical Engineering Dept.; Santos, V.R. dos [Petrobras/CENPES, Rio de Janeiro (Brazil); Santos, J.F. dos [GKSS Forschungszentrum Geesthacht GmbH (Germany)

1995-12-31T23:59:59.000Z

77

Summary of Dissimilar Metal Joining Trials Conducted by Edison Welding Institute  

SciTech Connect (OSTI)

Under the direction of the NASA-Glenn Research Center, the Edison Welding Institute (EWI) in Columbus, OH performed a series of non-fusion joining experiments to determine the feasibility of joining refractory metals or refractory metal alloys to Ni-based superalloys. Results, as reported by EWI, can be found in the project report for EWI Project 48819GTH (Attachment A, at the end of this document), dated October 10, 2005. The three joining methods used in this investigation were inertia welding, magnetic pulse welding, and electro-spark deposition joining. Five materials were used in these experiments: Mo-47Re, T-111, Hastelloy X, Mar M-247 (coarse-grained, 0.5 mm to several millimeter average grain size), and Mar M-247 (fine-grained, approximately 50 {micro}m average grain size). Several iterative trials of each material combination with each joining method were performed to determine the best practice joining method. Mo-47Re was found to be joined easily to Hastelloy X via inertia welding, but inertia welding of the Mo-alloy to both Mar M-247 alloys resulted in inconsistent joint strength and large reaction layers between the two metals. T-111 was found to join well to Hastelloy X and coarse-grained Mar M-247 via inertia welding, but joining to fine-grained Mar M-247 resulted in low joint strength. Magnetic pulse welding (MPW) was only successful in joining T-111 tubing to Hastelloy X bar stock. The joint integrity and reaction layer between the metals were found to be acceptable. This single joining trial, however, caused damage to the electromagnetic concentrators used in this process. Subsequent design efforts to eliminate the problem resulted in a loss of power imparted to the accelerating work piece, and results could not be reproduced. Welding trials of Mar M-247 to T-111 resulted in catastrophic failure of the bar stock, even at lower power. Electro-spark deposition joining of Mo-47Re, in which the deposited material was Hastelloy X, did not have a noticeable reaction layer. T-111 was found to have a small reaction layer at the interface with deposited Hastelloy X. Mar M-247 had a reaction layer larger than T-111. Hastelloy X joined well with a substrate of the same alloy, and throughout the experiments was found to have a density of {approx}99%, based on metallographic observations of porosity in the deposit. Of the three joining methods tested, inertial welding of bar stock appears to be the most mature at this time. MPW may be an attractive alternative due to the potential for high bond integrity, similar to that seen in explosion bonding. However, all three joining methods used in this work will require adaptation in order to join piping and tubing. Further investigations into the change in mechanical properties of these joints with time, temperature, irradiation, and the use of interlayers between the two materials must also be performed.

MJ Lambert

2005-11-18T23:59:59.000Z

78

Advanced Testing Techniques to Measure the PWSCC Resistance of Alloy 690 and its Weld Metals  

SciTech Connect (OSTI)

Wrought Alloy 600 and its weld metals (Alloy 182 and Alloy 82) were originally used in pressurized water reactors (PWRs) due to the material's inherent resistance to general corrosion in a number of aggressive environments and because of a coefficient of thermal expansion that is very close to that of low alloy and carbon steel. Over the last thirty years, stress corrosion cracking in PWR primary water (PWSCC) has been observed in numerous Alloy 600 component items and associated welds, sometimes after relatively long incubation times. The occurrence of PWSCC has been responsible for significant downtime and replacement power costs. As part of an ongoing, comprehensive program involving utilities, reactor vendors and engineering/research organizations, this report will help to ensure that corrosion degradation of nickel-base alloys does not limit service life and that full benefit can be obtained from improved designs for both replacement components and new reactors.

P.Andreson

2004-10-01T23:59:59.000Z

79

Microstructural, mechanical and weldability assessments of the dissimilar welds between ??- and ??-strengthened nickel-base superalloys  

SciTech Connect (OSTI)

Dissimilar welding of ??- and ??-strengthened nickel-base superalloys has been investigated to identify the relationship between the microstructure of the welds and the resultant mechanical and weldability characteristics. ??-Strengthened nickel-base Alloy 500 and ??-strengthened nickel-base Alloy 718 were used for dissimilar welding. Gas tungsten arc welding operations were utilized for performing the autogenous dissimilar welding. Alloy 500 and Alloy 718 base metals showed various types of phases, carbides, intermetallics and eutectics in their microstructure. The results for Alloy 500 weld metal showed severe segregation of titanium to the interdendritic regions. The Alloy 718 weld metal compositional analysis confirmed the substantial role of Nb in the formation of low-melting eutectic-type morphologies which can reduce the weldability. The microstructure of dissimilar weld metal with dilution level of 65% wt.% displayed semi-developed dendritic structure. The less segregation and less formation of low-melting eutectic structures caused to less susceptibility of the dissimilar weld metal to the solidification cracking. This result was confirmed by analytic modeling achievements. Dissolution of ??-Ni{sub 3}Nb precipitations took place in the Alloy 718 heat-affected zone leading to sharp decline of the microhardness in this region. Remelted and resolidified regions were observed in the partially-melted zone of Alloy 500 and Alloy 718. Nevertheless, no solidification and liquation cracking happened in the dissimilar welds. Finally, this was concluded that dissimilar welding of ??- and ??-strengthened nickel-base superalloys can successfully be performed. - Highlights: • Dissimilar welding of ??- and ??-strengthened nickel-base superalloys is studied. • Microstructural, mechanical and weldability aspects of the welds are assessed. • Microstructure of welds, bases and heat-affected zones is characterized in detail. • The type, morphology and distribution of the phases are thoroughly investigated. • Dissimilar welding is successfully performed without occurrence of any hot cracks.

Naffakh Moosavy, Homam, E-mail: homam_naffakh@iust.ac.ir [School of Metallurgy and Materials Engineering, Iran University of Science and Technology (IUST), Tehran 16846-13114 (Iran, Islamic Republic of); Aboutalebi, Mohammad-Reza; Seyedein, Seyed Hossein [School of Metallurgy and Materials Engineering, Iran University of Science and Technology (IUST), Tehran 16846-13114 (Iran, Islamic Republic of); Mapelli, Carlo [Dipartimento di Meccanica, Politecnico di Milano, Via La Massa 34, Milan 20156 (Italy)

2013-08-15T23:59:59.000Z

80

Surface preparation effects on GTA weld shape in JBK-75 stainless steel  

SciTech Connect (OSTI)

The results of a study are reported here on the effects of surface preparation on the shape of autogenous gas tungsten arc (GTA) welds in JBK-75, an austenitic precipitation hardenable stainless steel similar to A286. Minor changes in surface preparation produced substantial changes in the fusion zone shape and welding behavior of this alloy. Increased and more consistent depth of fusion (higher d/w ratios) along with improved arc stability and less arc wander resulted from wire brushing and other abrasive surface preparations, although chemical and machining methods did not produce any increase in depth of fusion. Abrasive treatments roughen the surface, increase the surface area, increase the surface oxide thickness, and entrap oxide. The increased weld d/w ratio is attributed to oxygen added to the weld pool from the surface oxide on the base metal. The added oxygen alters the surface-tension-driven fluid flow pattern in the weld pool. Increased depth of fusion in wire-fed U-groove weld joints also resulted when welding wire with a greater surface oxide thickness was used. Increasing the amount of wire brushing produced even deeper welds. However, a maximum in depth of fusion was observed with further wire brushing, beyond which weld fusion depth decreased.

Campbell, R.D.; Robertson, A.M. (AWS Precision Joining Center, Wheat Ridge, CO (United States)); Heiple, C.R. (EG and G Rocky Flats Plant, Golden (Colombia)); Sturgill, P.L.; Jamsay, R.

1993-02-01T23:59:59.000Z

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81

Nature and evolution of the fusion boundary in ferritic-austenitic dissimilar weld metals. Part 1 -- Nucleation and growth  

SciTech Connect (OSTI)

A fundamental investigation of fusion boundary microstructure evolution in dissimilar-metal welds (DMWs) between ferritic base metals and a face-centered-cubic (FCC) filler metal was conducted. The objective of the work presented here was to characterize the nature and character of the elevated-temperature fusion boundary to determine the nucleation and growth characteristics of DMWs. Type 409 ferritic stainless steel and 1080 pearlitic steel were utilized as base metal substrates, and Monel (70Ni-30Cu) was used as the filler metal. The Type 409 base metal provided a fully ferritic or body-centered-cubic (BCC) substrate at elevated temperatures and exhibited no on-cooling phase transformations to mask or disguise the original character of the fusion boundary. The 1080 pearlitic steel was selected because it is austenitic at the solidus temperature, providing an austenite substrate at the fusion boundary. The weld microstructure generated with each of the base metals in combination with Monel was fully austenitic. In the Type 409/Monel system, there was no evidence of epitaxial nucleation and growth as normally observed in homogeneous weld metal combinations. The fusion boundary in this system exhibited random grain boundary misorientations between the heat-affected zone (HAZ) and weld metal grains. In the 1080/Monel system, evidence of normal epitaxial growth was observed at the fusion boundary, where solidification and HAZ grain boundaries converged. The fusion boundary morphologies are a result of the crystal structure present along the fusion boundary during the initial stages of solidification. Based on the results of this investigation, a model for heterogeneous nucleation along the fusion boundary is proposed when the base and weld metals exhibit ferritic (BCC) and FCC crystal structures, respectively.

Nelson, T.W.; Lippold, J.C.; Mills, M.J.

1999-10-01T23:59:59.000Z

82

Welding for testability: An approach aimed at improving the ultrasonic testing of thick-walled austenitic and dissimilar metal welds  

SciTech Connect (OSTI)

Austenitic and dissimilar welds in thick walled components show a coarse grained, dendritic microstructure. Therefore, ultrasonic testing has to deal with beam refraction, scattering and mode conversion effects. As a result, the testing techniques typically applied for isotropic materials yield dissatisfying results. Most approaches for improvement of ultrasonic testing have been based on modeling and improved knowledge of the complex wave propagation phenomena. In this paper, we discuss an alternative approach: is it possible to use a modified welding technology which eliminates the cause of the UT complications, i.e. the large-grained structure of the weld seams? Various modification parameters were tested, including: TIG current pulsing, additional DC and AC magnetic fields, and also additional external vibrations during welding. For all welds produced under different conditions, the grain structure of the weld seam was characterized by optical and GIUM microstructure visualizations on cross sections, wave field propagation measurements, and ultrasonic tests of correct detectability of flaws. The mechanical properties of the welds were also tested.

Wagner, Sabine; Dugan, Sandra [Materials Testing Institute University of Stuttgart (MPA), Pfaffenwaldring 32, 70569 Stuttgart (Germany); Barth, Martin; Schubert, Frank; Köhler, Bernd [Fraunhofer Institute for Nondestructive Testing, Dresden Branch (IZFP-D), Maria-Reiche-Str. 2, 01109 Dresden (Germany)

2014-02-18T23:59:59.000Z

83

WELDING RESEARCH -S249WELDING JOURNAL  

E-Print Network [OSTI]

thick that the reduction in the number of passes is dramatic, the time needed for additional positioning agent on the work- piece surface during gas tungsten arc welding to modify the flow in the weld pool mixtures of inorganic powders suspended in a volatile medium, for different materials. This method, re

Zhang, YuMing

84

Review of Dissimilar Metal Welding for the NGNP Helical-Coil Steam Generator  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) is currently funding research and development of a new high temperature gas cooled reactor (HTGR) that is capable of providing high temperature process heat for industry. The steam generator of the HTGR will consist of an evaporator economizer section in the lower portion and a finishing superheater section in the upper portion. Alloy 800H is expected to be used for the superheater section, and 2.25Cr 1Mo steel is expected to be used for the evaporator economizer section. Dissimilar metal welds (DMW) will be needed to join these two materials. It is well known that failure of DMWs can occur well below the expected creep life of either base metal and well below the design life of the plant. The failure time depends on a wide range of factors related to service conditions, welding parameters, and alloys involved in the DMW. The overall objective of this report is to review factors associated with premature failure of DMWs operating at elevated temperatures and identify methods for extending the life of the 2.25Cr 1Mo steel to alloy 800H welds required in the new HTGR. Information is provided on a variety of topics pertinent to DMW failures, including microstructural evolution, failure mechanisms, creep rupture properties, aging behavior, remaining life estimation techniques, effect of environment on creep rupture properties, best practices, and research in progress to improve DMW performance. The microstructure of DMWs in the as welded condition consists of a sharp chemical concentration gradient across the fusion line that separates the ferritic and austenitic alloys. Upon cooling from the weld thermal cycle, a band of martensite forms within this concentration gradient due to high hardenability and the relatively rapid cooling rates associated with welding. Upon aging, during post weld heat treatment (PWHT), and/or during high temperature service, C diffuses down the chemical potential gradient from the ferritic 2.25Cr 1Mo steel toward the austenitic alloy. This can lead to formation of a soft C denuded zone near the interface on the ferritic steel, and nucleation and growth of carbides on the austenitic side that are associated with very high hardness. These large differences in microstructure and hardness occur over very short distances across the fusion line (~ 50 100 ?m). A band of carbides also forms along the fusion line in the ferritic side of the joint. The difference in hardness across the fusion line increases with increasing aging time due to nucleation and growth of the interfacial carbides. Premature failure of DMWs is generally attributed to several primary factors, including: the sharp change in microstructure and mechanical properties across the fusion line, the large difference in coefficient of thermal expansion (CTE) between the ferritic and austenitic alloys, formation of interfacial carbides that lead to creep cavity formation, and preferential oxidation of the ferritic steel near the fusion line. In general, the large gradient in mechanical properties and CTE serve to significantly concentrate the stress along the fusion where a creep susceptible microstructure has evolved during aging. Presence of an oxide notch can concentrate the stress even further. Details of the failure mechanism and the relative importance of each factor varies.

John N. DuPont

2010-03-01T23:59:59.000Z

85

CHARACTERIZATION OF DEFECTS IN ALLOY 152, 52 AND 52M WELDS  

SciTech Connect (OSTI)

Defect distributions have been documented by optical metallography, scanning electron microscopy and electron backscatter diffraction in alloy 152 and 52 mockups welds, alloy 52 and 52M overlay mockups and an alloy 52M inlay. Primary defects were small cracks at grain boundaries except for more extensive cracking in the dilution zone of an alloy 52 overlay on 304SS. Detailed characterizations of the dilution zone cracks were performed by analytical transmission electron microscopy identifying grain boundary titanium-nitride precipitation associated with the intergranular separations. I. INTRODUCTION Weldments continue to be a primary location of stress-corrosion cracking (SCC) in light-water reactor systems. While problems related to heat-affected-zone (HAZ) sensitization and intergranular (IG) SCC of austenitic stainless alloys in boiling-water reactors (BWRs) have been significantly reduced, SCC has now been observed in HAZs of non-sensitized materials and in dissimilar metal welds where Ni-base alloy weld metals are used. IGSCC in weld metals has been observed in both BWRs and pressurized water reactors (PWRs) with recent examples for PWR pressure vessel penetrations producing the most concern. This has led to the replacement of alloy 600/182/82 welds with higher Cr, more corrosion-resistant replacement materials (alloy 690/152/52/52M). Complicating this issue has been a known susceptibility to cracking during welding [1-7] of these weld metals. There is a critical need for an improved understanding of the weld metal metallurgy and defect formation in Ni-base alloy welds to effectively assess long-term performance. A series of macroscopic to microscopic examinations were performed on available mockup welds made with alloy 52 or alloy 152 plus selected overlay and inlay mockups. The intent was to expand our understanding of weld metal structures in simulated LWR service components with a focus on as-welded defects. Microstructural features, defect distributions, defect characteristics and weld residual strains were examined by optical metallography, scanning electron microscopy, electron backscatter diffraction and transmission electron microscopy. Industry-supplied mock-up welds were characterized including alloy 52 and 152 weldments, alloy 52M overlay and inlay welds, and an alloy 52 overlay. II. WELDMENTS II.A. Alloy 52 and 152 Weld Mockups The alloy 52 and 152 weld mockups were fabricated by MHI for the Kewaunee reactor and were obtained from the EPRI NDE Center. The mockups were U-groove welds joining two plates of 304SS as shown in Figure 1. Alloy 152 butter (heat 307380) was placed on the U-groove surface for both mockups by shielded metal arc welding (SMAW). For the alloy 152 weld mockup, the alloy 152 fill (heat 307380) was also applied using SMAW while for the alloy 52 weld mockup, the alloy 52 fill (heat NX2686JK) was applied using gas tungsten arc welding (GTAW). Welding parameters for the fill materials were substantially different with the alloy 152 SMAW having a deposition speed of 4-25 cm/min with a current of 95-145 A and the alloy 52 GTAW having a deposition speed of 4-10 cm/min with a current of 150-300 A. One prominent feature in these mockup welds is the presence of a crack starting at the 304SS butt joint at the bottom of the U-groove and extending up into the weld. It appears that the 304SS plate on either side of the butt joint acted as an anchor for the weld resulting in a stress rise across the slit that drove crack formation and extension up into the fill weld. As will be shown in the next section, the extent of the cracking around this stress riser was much greater in the MHI 52 weld mockup.

Bruemmer, Stephen M.; Toloczko, Mychailo B.; Olszta, Matthew J.; Seffens, Rob J.; Efsing, Pal G.

2009-08-27T23:59:59.000Z

86

Spatial and time-dependent distribution of plasma parameters in the metal-halide arc lamp  

E-Print Network [OSTI]

It was shown by several authors that closed high pressure arc a.c. discharge in mercury vapors with addition of metal halide cannot be described in frames of the local thermodynamic equilibrium (LTE) model. However some plasma parameters (electron and high lying excited states densities as well as Hg metastable levels densities) are assumed to be in equilibrium with electron temperature and these assumptions are applied in plasma diagnostics. To verify these supposition the method of local plasma spectroscopy based on spatial and temporal distribution of spectral line profiles was developed. The experimental set up is based on diffraction spectrometer with large aperture, spatial scanning device and photodetector, which allows to carry out the measurements in chosen phases of current period. The software for data acquisition and processing is based on LabVIEW system. The original method of joint data processing was applied to data arrays containing spatial, spectral and temporal distribution of a source surfa...

Khakhaev, A; Ekimov, K; Soloviev, A; Khakhaev, Anatoly; Luizova, Lidia; Ekimov, Konstantin; Soloviev, Alexey

2004-01-01T23:59:59.000Z

87

The Behaviour of Base Metals in Arc-Type Magmatic-Hydrothermal Systems Insights from Merapi Volcano,  

E-Print Network [OSTI]

zone stratovolcanoes provide important windows on the magmatic-hydrothermal processes at playThe Behaviour of Base Metals in Arc-Type Magmatic- Hydrothermal Systems ­ Insights from Merapi systems include a shallow magmatic reservoir (the porphyry stock), an overlying hydrothermal cell, its

Barnes, Sarah-Jane

88

Generation of high charge state metal ion beams by electron cyclotron resonance heating of vacuum arc plasma in cusp trap  

SciTech Connect (OSTI)

A method for generating high charge state heavy metal ion beams based on high power microwave heating of vacuum arc plasma confined in a magnetic trap under electron cyclotron resonance conditions has been developed. A feature of the work described here is the use of a cusp magnetic field with inherent ''minimum-B'' structure as the confinement geometry, as opposed to a simple mirror device as we have reported on previously. The cusp configuration has been successfully used for microwave heating of gas discharge plasma and extraction from the plasma of highly charged, high current, gaseous ion beams. Now we use the trap for heavy metal ion beam generation. Two different approaches were used for injecting the vacuum arc metal plasma into the trap - axial injection from a miniature arc source located on-axis near the microwave window, and radial injection from sources mounted radially at the midplane of the trap. Here, we describe preliminary results of heating vacuum arc plasma in a cusp magnetic trap by pulsed (400 {mu}s) high power (up to 100 kW) microwave radiation at 37.5 GHz for the generation of highly charged heavy metal ion beams.

Nikolaev, A. G.; Savkin, K. P.; Oks, E. M.; Vizir, A. V.; Yushkov, G. Yu. [High Current Electronics Institute, Siberian Division of Russian Academy Science, Tomsk 634055 (Russian Federation); Vodopyanov, A. V.; Izotov, I. V.; Mansfeld, D. A. [Institute of Applied Physics, Russian Academy of Science, Nizhniy Novgorod 603950 (Russian Federation)

2012-02-15T23:59:59.000Z

89

Dissimilar-weld failure analysis and development. Comparative behavior of similar and dissimilar welds. Final report. [Welds of 2-1/4Cr-1Mo to 2-1/4Cr-1Mo using 2-1/4Cr-1Mo filler material; and austenitic to ferritic steel welds made by fusion welding alloy-800H to 2-1/4Cr-1Mo using nickel base filler metal ERNiCr-3  

SciTech Connect (OSTI)

The 593/sup 0/C (1100/sup 0/F) stress rupture behavior of similar metal welds (SMWs) and dissimilar metal welds (DMWs) was investigated under cyclic load and cyclic temperature conditions to provide insight into the question, ''Why do DMWs fail sooner than SMWs in the fossil fuel boilers.'' The weld joints of interest were an all ferritic steel SMW made by fusion welding 2-1/4Cr-1Mo to 2-1/4Cr-1Mo using 2-1/4Cr-1Mo filler metal and an austenitic to ferritic steel DMW made by fusion welding Alloy-800H to 2-1/4Cr-1Mo using a nickel base filler metal ERNiCr-3. The stress rupture behavior obtained on cross weld specimens was similar for both types of welds with only a 20% reduction in rupture life for the DMW. For rupture times less than 1500 hours, failures occurred in the 2-1/4Cr-1Mo base metal whereas, for rupture times greater than 1500 hours, failures occurred in the 2-1/4Cr-1Mo heat affected zone (HAZ). The HAZ failures exhibited a more brittle appearance than the base metal failures for both types of welds and it appears that the life of both joints was limited by the stress rupture properties of the HAZ. These results support the hypothesis that increased residual stresses due to abrupt changes in hardness (strength) of metals involved are the major contributors to the reduction in life of DMWs as compared to SMWs. 10 refs., 15 figs., 7 tabs.

Busboom, H.; Ring, P.J.

1986-07-01T23:59:59.000Z

90

Evaluation of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station  

SciTech Connect (OSTI)

During a recent inservice inspection (ISI) of a dissimilar metal weld (DMW) in an inlet (hot leg) steam generator nozzle at North Anna Power Station Unit 1, several axially oriented flaws went undetected by the licensee's manual ultrasonic testing (UT) technique. The flaws were subsequently detected as a result of outside diameter (OD) surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the DMW. Further ultrasonic tests were then performed, and a total of five axially oriented flaws, classified as primary water stress corrosion cracking (PWSCC), were detected in varied locations around the weld circumference.

Anderson, Michael T.; Diaz, Aaron A.; Doctor, Steven R.

2012-06-01T23:59:59.000Z

91

High Charge State Ions Extracted from Metal Plasmas in the Transition Regime from Vacuum Spark to High Current Vacuum Arc  

SciTech Connect (OSTI)

Metal ions were extracted from pulsed discharge plasmas operating in the transition region between vacuum spark (transient high voltage of kV) and vacuum arc (arc voltage ~;; 20 V). At a peak current of about 4 kA, and with a pulse duration of 8 ?s, we observed mean ion charges states of about 6 for several cathode materials. In the case of platinum, the highest average charge state was 6.74 with ions of charge states as high as 10 present. For gold we found traces of charge state 11, with the highest average charge state of 7.25. At currents higher than 5 kA, non-metallic contaminations started to dominate the ion beam, preventing further enhancement of the metal charge states.

Yushkov, Georgy Yu.; Anders, A.

2008-06-19T23:59:59.000Z

92

Weldability and weld performance of a special grade Hastelloy-X modified for high-temperature gas-cooled reactors  

SciTech Connect (OSTI)

The characteristics of weld defects in the electron beam (EB) welding and the tungsten inert gas (TIG) arc welding for Hastelloy-XR, a modified version of Hastelloy-X, are clarified through the bead-on-plate test and the Trans-Varestraint test. Based on the results, weldabilities on EB and TIG weldings for Hastelloy-XR are discussed and found to be almost the same as Hastelloy-X. The creep rupture behaviors of the welded joints are evaluated by employing data on creep properties of the base and the weld metals. According to the evaluation, the creep rupture strength of the EB-welded joint may be superior to that of the TIG-welded joint. The corrosion test in helium containing certain impurities is conducted for the weld metals. There is no significant difference of such corrosion characteristics as weight gain, internal oxidation, depleted zone, and so on between the base and the weld metals. Those are superior to Hastelloy-X.

Shimizu, S.; Mutoh, Y.

1984-07-01T23:59:59.000Z

93

Intelligent Control of Modular Robotic Welding Cell  

SciTech Connect (OSTI)

Although robotic machines are routinely used for welding, such machines do not normally incorporate intelligent capabilities. We are studying the general problem of formulating usable levels of intelligence into welding machines. From our perspective, an intelligent machine should: incorporate knowledge of the welding process, know if the process is operating correctly, know if the weld it is making is good or bad, have the ability to learn from its experience to perform welds, and be able to optimize its own performance. To this end, we are researching machine architecture, methods of knowledge representation, decision making and conflict resolution algorithms, methods of learning and optimization, human/machine interfaces, and various sensors. This paper presents work on the machine architecture and the human/machine interface specifically for a robotic, gas metal arc welding cell. Although the machine control problem is normally approached from the perspective of having a central body of control in the machine, we present a design using distributed agents. A prime goal of this work is to develop an architecture for an intelligent machine that will support a modular, plug and play standard. A secondary goal of this work is to formulate a human/machine interface that treats the human as an active agent in the modular structure.

Smartt, Herschel Bernard; Kenney, Kevin Louis; Tolle, Charles Robert

2002-04-01T23:59:59.000Z

94

Formation of cobalt silicide from filter metal vacuum arc deposited films  

SciTech Connect (OSTI)

The thermal reaction of Co film deposited on Si (111) surfaces by a high current filter metal vacuum arc (FMEVAD) system has been studied. After deposition the films were annealed over the 400-900 C temperature range for 30 min. Rutherford Backscattering Spectrometry (RBS) was used to characterize the elemental depth distributions in the films subjected to different annealing temperatures. Ordered chemical phases were determined by glancing-incidence X-ray diffraction (GIXRD) and the morphology was determined by cross section transmission electron microscopy (TEM). The results show that the phases formed are Co2Si at 400 C, CoSi + CoO at 500 C, CoSi + CoSi2 at 600 C, and CoSi2 at (700-800 C). At 900 C, CoSi2 was formed with a mixture of cubic cobalt and probably an amorphous cobalt oxide surface layer. The interface morphology was a rough cusp-like crenellation at 600 C which became less pronounced after annealing at 800 C.

Whitlow, Harry J.; Zhang, Yanwen; Wang, Chong M.; McCready, David E.; Zhang, Tonghe; Wu, Yuguang

2006-06-01T23:59:59.000Z

95

Product/metal ratio (PMR): A novel criterion for the evaluation of electrolytes on micro-arc oxidation (MAO) of Mg and its alloys  

Science Journals Connector (OSTI)

Product/metal ratio (PMR...) was introduced as a novel criterion for the evaluation of electrolytes on micro-arc oxidation (MAO) of Mg and its alloys....PBR), focused on the roles of electrolytes for the compactn...

LaiWen Song; YingWei Song; DaYong Shan; GuoYi Zhu…

2011-10-01T23:59:59.000Z

96

Microstructure/property relationships in dissimilar welds between duplex stainless steels and carbon steels  

SciTech Connect (OSTI)

The metallurgical characteristics, toughness and corrosion resistance of dissimilar welds between duplex stainless steel Alloy 2205 and carbon steel A36 have been evaluated. Both duplex stainless steel ER2209 and Ni-based Alloy 625 filler metals were used to join this combination using a multipass, gas tungsten arc welding (GTAW) process. Defect-free welds were made with each filler metal. The toughness of both the 625 and 2209 deposits were acceptable, regardless of heat input. A narrow martensitic region with high hardness was observed along the A36/2209 fusion boundary. A similar region was not observed in welds made with the 625 filler metal. The corrosion resistance of the welds made with 2209 filler metal improved with increasing heat input, probably due to higher levels of austenite and reduced chromium nitride precipitation. Welds made with 625 exhibited severe attack in the root pass, while the bulk of the weld was resistant. This investigation has shown that both filler metals can be used to joint carbon steel to duplex stainless steels, but that special precautions may be necessary in corrosive environments.

Barnhouse, E.J. [Weirton Steel Corp., WV (United States); Lippold, J.C. [Ohio State Univ., Columbus, OH (United States)

1998-12-01T23:59:59.000Z

97

In-process acoustic emission monitoring of dissimilar metal welding: Final report  

SciTech Connect (OSTI)

A system to provide real-time, in-process acoustic emission monitoring to detect and locate flaws in bimetallic welds has been demonstrated. This system could provide reliable inspection of critical welds in cases where conventional NDE would be costly or impossible to apply. Tests were completed on four sample welds to determine the sensitivity of the system. Artificial flaws were introduced into two test samples and the acoustic emission results were verified by radiography and visual inspection techniques.

Not Available

1989-08-01T23:59:59.000Z

98

Determination of welding fume size with time using E7018 electrodes and A131B base metal  

E-Print Network [OSTI]

Welders are exposed to various hazardous fumes in the course of their work. Health hazard levels from welding fumes range from relatively little or no hazard to death. To incur these hazards the worker must inhale and retain the particulates in the lung...'. s are inhaled. These hazards range from little or no effect, such as metal fume fever, to death. The result depends on the chemical nature of the material, the length of exposure, and the amount and size of the fume particles. Metal fNne fever is a...

Owen, Richard James

2012-06-07T23:59:59.000Z

99

Steam generator conceptual design for the modular HTGR - Dissimilar metal weld considerations  

SciTech Connect (OSTI)

The steam generator for the current Modular High Temperature Gas-Cooled Reactor (MHTGR) has evolved from a technology basis developed in U.S. and European gas-cooled reactor programs. The MHTGR steam generator is a vertically-oriented, counterflow, shell-and-tube, once-through, non-reheat, helical heat exchanger with helium on the shell side and water/steam in the tubes. In the MHTGR applications, the normal operating temperatures of the steam generator tubes can be as high as 638/sup 0/C (1180/sup 0/F). Concerns such as cost, creep strength, steam side scaling and stress corrosion cracking often lead to a design decision to use two different tube materials, one for the evaporating portion and another for the superheating portion of the steam generator. The current MHTGR steam generator design utilizes 2 1/4 CR - 1 Mo material for the economizer/evaporator/initial superheater tube section and Alloy 800H material for the finishing superheat tube section. Therefore, a dissimilar metal weld (DMW) is incorporated in each tube circuit. This feature of the design imposes certain important constraints on the steam generator designer. This paper presents an overview of the MHTGR steam generator conceptual design, and then focuses on the DMW considerations and how these have influenced the design configuration.

Spring, A.H.; Basol, M.

1987-01-01T23:59:59.000Z

100

Welding Hot Cracking of Side Shell of Drilling-Well Oil Storage Ship  

Science Journals Connector (OSTI)

...Cracks were found in the weld metal (WM) of weld-section of side shell of drilling-well oil storage ship when performing post weld radiographic...

Zhi-wei Yu; Xiao-lei Xu

2014-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Effects of thermal aging on Stress Corrosion Cracking and mechanical properties of stainless steel weld metals  

E-Print Network [OSTI]

Stress Corrosion Cracking (SCC) in and around primary loop piping welds in Boiling Water Reactors has been observed worldwide as plants continue to operate at temperatures and pressures near 2880C (5500F) and 6.9 MPa (1000 ...

Hixon, Jeff

2006-01-01T23:59:59.000Z

102

Effect of multiple repairs in girth welds of pipelines on the mechanical properties  

SciTech Connect (OSTI)

This work presents the results of multiple weld repairs in the same area in seamless API X-52 microalloyed steel pipe. Four conditions of shielded metal arc welding repairs and one as-welded specimen of the girth weld were characterized to determine changes in the microstructure, grain size in the heat affected zone, and to evaluate their effect on the mechanical properties of the weld joints. The mechanical properties by means of tension tests, Charpy-V impact resistance and Vickers hardness of the welds were analyzed. The results indicate that significant changes are not generated in the microstructural constituents of the heat affected zone. Grain growth in the heat affected zone at the specimen mid-thickness with the number of repairs was observed. Tensile strength of the weld joints meets the requirement of the API 1104 standard even after the fourth weld repair. Significant reduction in Charpy-V impact resistance with the number of weld repairs was found when the notch location was in the intersection of the fusion line with the specimen mid-thickness. A significant increase in the Vickers hardness of the heat affected zone occurred after the first repair and a gradual decrease in the Vickers hardness occurred as the number of repairs increases.

Vega, O.E.; Hallen, J.M. [Departamento de Ingenieria Metalurgica, ESIQIE-IPN, Laboratorios Pesados de Metalurgia, UPALM, Zacatenco, C.P. 07738, Mexico D.F. (Mexico); Villagomez, A. [Construcciones Maritimas Mexicanas, CMM-PROTEXA, Av. Periferica s/n, Fracc. Lomas de Holche, C.P. 24120, Cd. del Carmen, Campeche (Mexico); Contreras, A. [Instituto Mexicano del Petroleo, Investigacion en Ductos, Corrosion y Materiales, Eje Central Lazaro Cardenas Norte 152 Col. San Bartolo Atepehuacan, C.P. 07730, Mexico D.F. (Mexico)], E-mail: acontrer@imp.mx

2008-10-15T23:59:59.000Z

103

Roughening and removal of surface contamination from beryllium using negative transferred-arc cleaning  

SciTech Connect (OSTI)

Negative transferred-arc (TA) cleaning has been used extensively in the aerospace industry to clean and prepare surfaces prior to plasma spraying of thermal barrier coatings. This non-line of sight process can improve the bond strength of plasma sprayed coatings to the substrate material by cleaning and macroscopically roughening the surface. A variation of this cleaning methodology is also used in gas tungsten arc (GTA) welding to cathodically clean the surfaces of aluminum and magnesium prior to welding. Investigations are currently being performed to quantify the degree in which the negative transferred-arc process can clean and roughen metal surfaces. Preliminary information will be reported on the influence of processing conditions on roughening and the removal of carbon and other contaminates from the surface of beryllium. Optical, spectral and electrical methods to quantify cleaning of the surface will also be discussed. Applications for this technology include chemical-free precision cleaning of beryllium components.

Castro, R.G.; Hollis, K.J.; Elliott, K.E. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

1997-12-01T23:59:59.000Z

104

Influence of welding passes on grain orientation -the example of a multi-pass V-weld.  

E-Print Network [OSTI]

Evaluation (CANDE), derived from a dissimilar metal weld (DMW) with buttering. Comparisons are made using

Paris-Sud XI, Université de

105

A comparison of LBW and GTAW processes in miniature closure welds  

SciTech Connect (OSTI)

When small electronic components with glass-to-metal seals are closure welded, residual stresses developed in the glass are of concern. If these stresses exceed allowable tensile levels` the resulting weld-induced seal failure may cause the entire component to be scrapped or reworked at substantial cost. Conventional wisdom says the best welding process for these applications is that which provides the least heat input, and that Laser Beam Welding (LBW) provides less heat input than Gas Tungsten Arc Welding. (GTAW); however, other concerns such as weld fit-up, part variability, and material weldability can modify the final choice of a welding process. In this paper we compare the characteristic levels of heat input and the residual stresses generated in the glass seals for the two processes (as calculated by 3D Finite Element Analysis) as a function of heat input and travel speed, and contrast some of the other manufacturing decisions that must be made to choose a production process. The geometry chosen is a standing edge corner weld in a cylindrical container about 20 mm diameter by 35 mm tall. Four metal pins are glassed into the part lid. The stresses calculated to result from continuous wave C0{sub 2} LBW are compared with those that result from GTAW. The total energy required by the laser weld is significantly less than for the equivalent size GTA weld. The energy input required for a given size weld is inversely proportional to the travel speed, but approaches a saturation level as the travel speed increases. LBW travel speeds ranging from 10 mm/sec to 50 mm/sec were examined.

Knorovsky, G.A.; Fuerschbach, P.W.; Gianoulakis, S.E.; Burchett, S.N.

1995-07-01T23:59:59.000Z

106

Analysis of a Defected Dissimilar Metal Weld in a PWR Power Plant  

SciTech Connect (OSTI)

During the refueling outage 2000, inspections of the RC-loops of one of the Ringhals PWR-units, Ringhals 4, indicated surface breaking defects in the axial direction of the piping in a dissimilar weld between the Low alloy steel nozzle and the stainless safe end in the hot leg. In addition some indications were found that there were embedded defects in the weld material. These defects were judged as being insignificant to the structural integrity. The welds were inspected in 1993 with the result that no significant indications were found. The weld it self is a double U weld, where the thickness of the material is ideally 79,5 mm. Its is constructed by Inconel 182 weld material. At the nozzle a buttering was applied, also by Inconel 182. The In-service inspection, ISI, of the object indicated four axial defects, 9-16 mm deep. During fabrication, the areas where the defects are found were repaired at least three times, onto a maximum depth of 32 mm. To evaluate the defects, 6 boat samples from the four axial defects were cut from the perimeter and shipped to the hot-cell laboratory for further examination. This examination revealed that the two deep defects had been under sized by the ISI outside the requirement set by the inspection tolerances, while the two shallow defects were over sized, but within the tolerances of the detection system. When studying the safety case it became evident that there were several missing elements in the way this problems is handled with respect to the Swedish safety evaluation code. Among these the most notable at the beginning was the absence of reliable fracture mechanical data such as crack growth laws and fracture toughness at elevated temperature. Both these questions were handled by the project. The fracture mechanical evaluation has focused on a fit for service principal. Thus defects both in the unaffected zones and the disturbed zones, boat sample cutouts, of the weld have been analyzed. With reference to the Swedish safety evaluation system in accordance to the regulatory demands, a safety evaluation was performed using the R6-method. The failure assessment diagram is modified by the addition of the ASME XI safety factors both for limit load analysis and fracture assessment. This results in a very high conservatism since the secondary stresses such as residual stresses are high in the area. In order to quantify this effect an analysis in accordance to ASME IWB-3640, App. C was performed. This analysis provides the decision-makers with a sensitivity study; important to have to value the real risk of any missed defects in the area. (authors)

Efsing, P. [Barseback Kraft AB, P.O. Box 524, Loddekopinge SE-246 25 (Sweden); Lagerstrom, J. [Vattenfall AB, Ringhals, 430 22 Vaeroebacka (Sweden)

2002-07-01T23:59:59.000Z

107

ARC DISCHARGE SYNTHESIS AND MORPHOLOGY CONTROL OF EARLY TRANSITION METAL CARBIDE NANOPATICLES.  

E-Print Network [OSTI]

??This work is directed to the understanding of the synthesis and morphology control of early transition metal carbides. Chapter 1 gives an introduction to fcc… (more)

Grove , David

2010-01-01T23:59:59.000Z

108

Gas tungsten arc welder with electrode grinder  

DOE Patents [OSTI]

A welder for automated closure of fuel pins by a gas tungsten arc process in which a rotating length of cladding is positioned adjacent a welding electrode in a sealed enclosure. An independently movable axial grinder is provided in the enclosure for refurbishing the used electrode between welds.

Christiansen, David W. (Kennewick, WA); Brown, William F. (West Richland, WA)

1984-01-01T23:59:59.000Z

109

Weldability and keyhole behavior of Zn-coated steel in remote welding using disk laser with scanner head  

Science Journals Connector (OSTI)

Zinc-coated steels are widely used in automobile bodies. Laser welding which offers a lot of advantages over the conventional welding with metal active gas welding CO2 arc etc. in terms of improved weld quality high-speed and easy automation has been developed for cars. However in laser lap welding of zinc-coated steel sheets without gaps defects such as underfilled beads or porosity were easily formed due to higher pressure of zinc vapor trapped in the molten pool because of the lower boiling point of zinc (1180?K) with respect to the melting point of steel (Fe 1803?K). Laser lap welding results of two Zn-coated steel sheets have been reported. However there are not enough data for welding of three Zn-coated steel sheets. Therefore to understand laser lap weldability of three Zn-coated steel sheets lap welding of two or three sheets with and without gaps was performed using 16?kW disk laser apparatus with a scanner head and molten pool motions spattering and keyhole behavior during welding were observed by high-speed video cameras and x-ray transmission real-time imaging apparatus. Lap welding of three steel sheets was difficult but acceptably good welds were produced in sheets with upper and lower gaps of 0.1 and 0.1?mm 0.1 and 0.2?mm or 0.2 and 0.1?mm respectively. Bubble generation leading to porosity formation was observed and it was confirmed that welding phenomena were different depending upon the gap levels.

Jong-Do Kim

2013-01-01T23:59:59.000Z

110

Friction stir welding and processing of oxide dispersion strengthened (ODS) alloys  

DOE Patents [OSTI]

A method of welding including forming a filler material of a first oxide dispersoid metal, the first oxide dispersoid material having first strengthening particles that compensate for decreases in weld strength of friction stir welded oxide dispersoid metals; positioning the filler material between a first metal structure and a second metal structure each being comprised of at least a second oxide dispersoid metal; and friction welding the filler material, the first metal structure and the second metal structure to provide a weld.

Ren, Weiju

2014-11-11T23:59:59.000Z

111

Method for enhanced control of welding processes  

DOE Patents [OSTI]

Method and system for producing high quality welds in welding processes, in general, and gas tungsten arc (GTA) welding, in particular by controlling weld penetration. Light emitted from a weld pool is collected from the backside of a workpiece by optical means during welding and transmitted to a digital video camera for further processing, after the emitted light is first passed through a short wavelength pass filter to remove infrared radiation. By filtering out the infrared component of the light emitted from the backside weld pool image, the present invention provides for the accurate determination of the weld pool boundary. Data from the digital camera is fed to an imaging board which focuses on a 100.times.100 pixel portion of the image. The board performs a thresholding operation and provides this information to a digital signal processor to compute the backside weld pool dimensions and area. This information is used by a control system, in a dynamic feedback mode, to automatically adjust appropriate parameters of a welding system, such as the welding current, to control weld penetration and thus, create a uniform weld bead and high quality weld.

Sheaffer, Donald A. (Livermore, CA); Renzi, Ronald F. (Tracy, CA); Tung, David M. (Livermore, CA); Schroder, Kevin (Pleasanton, CA)

2000-01-01T23:59:59.000Z

112

Laser Welding and Post Weld Treatment of Modified 9Cr-1MoVNb Steel [Laser  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Welding of Metals > Laser Welding of Metals > Laser Welding and Post Weld Treatment of Modified 9Cr-1MoVNb Steel Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Welding of Metals Laser Welding and Post Weld Treatment of Modified 9Cr-1MoVNb Steel Zhiyue Xu Nuclear Engineering Division of Argonne National Laboratory

113

Narrow groove welding gas diffuser assembly and welding torch  

DOE Patents [OSTI]

A diffuser assembly is provided for narrow groove welding using an automatic gas tungsten arc welding torch. The diffuser assembly includes a manifold adapted for adjustable mounting on the welding torch which is received in a central opening in the manifold. Laterally extending manifold sections communicate with a shield gas inlet such that shield gas supplied to the inlet passes to gas passages of the manifold sections. First and second tapered diffusers are respectively connected to the manifold sections in fluid communication with the gas passages thereof. The diffusers extend downwardly along the torch electrode on opposite sides thereof so as to release shield gas along the length of the electrode and at the distal tip of the electrode. The diffusers are of a transverse width which is on the order of the thickness of the electrode so that the diffusers can, in use, be inserted into a narrow welding groove before and after the electrode in the direction of the weld operation.

Rooney, Stephen J. (East Berne, NY)

2001-01-01T23:59:59.000Z

114

Corrosion Resistant Cladding by YAG Laser Welding in Underwater Environment  

SciTech Connect (OSTI)

It is known that stress-corrosion cracking (SCC) will occur in nickel-base alloys used in Reactor Pressure Vessel (RPV) and Internals of nuclear power plants. A SCC sensitivity has been evaluated by IHI in each part of RPV and Internals. There are several water level instrumentation nozzles installed in domestic BWR RPV. In water level instrumentation nozzles, 182 type nickel-base alloys were used for the welding joint to RPV. It is estimated the SCC potential is high in this joint because of a higher residual stress than the yield strength (about 400 MPa). This report will describe a preventive maintenance method to these nozzles Heat Affected Zone (HAZ) and welds by a corrosion resistant cladding (CRC) by YAG Laser in underwater environment (without draining a reactor water). There are many kinds of countermeasures for SCC, for example, Induction Heating Stress Improvement (IHSI), Mechanical Stress Improvement Process (MSIP) and so on. A YAG laser CRC is one of them. In this technology a laser beam is used for heat source and irradiated through an optical fiber to a base metal and SCC resistant material is used for welding wires. After cladding the HAZ and welds are coated by the corrosion resistant materials so their surfaces are improved. A CRC by gas tungsten arc welding (GTAW) in an air environment had been developed and already applied to a couple of operating plants (16 Nozzles). This method was of course good but it spent much time to perform because of an installation of some water-proof working boxes to make a TIG-weldability environment. CRC by YAG laser welding in underwater environment has superior features comparing to this conventional TIG method as follows. At the viewpoint of underwater environment, (1) an outage term reduction (no drainage water). (2) a radioactive exposure dose reduction for personnel. At that of YAG laser welding, (1) A narrower HAZ. (2) A smaller distortion. (3) A few cladding layers. A YAG laser CRC test in underwater environment was carried out in the different welding position, horizontal, vertical upward and downward. The soundness of cladding layers (about 3 mm) is confirmed in visual and penetration test, and cross section observation. In the application to the actual plants, it is preferable to reduce the start and end point numbers of beads with which a defect is easy to cause. Therefore a special welding equipment for a YAG laser CRC that could weld continuously was developed. (authors)

Tsutomi Kochi; Toshio Kojima; Suemi Hirata; Ichiro Morita; Katsura Ohwaki [Ishikawajima-Harima Heavy Industries Company Ltd., 1 Shin-Nakaharacho, Isogoku, Yokohama 235-8501 (Japan)

2002-07-01T23:59:59.000Z

115

Identification of the selective corrosion existing at the seam weld of electric resistance-welded pipes  

Science Journals Connector (OSTI)

Abstract The selective corrosion existing at the seam weld of high frequency electric resistance welded pipes of carbon steel with low sulfur content in electrolyte solutions is revealed by localized electrochemical measurements. The seam weld, mainly consisted of ferrite, has more negative open circuit potential and higher anodic dissolution current density than the base metal consisting ferrite and pearlite. Between the seam weld and the base metal, there is a galvanic coupling effect accelerating the dissolution kinetics of the seam weld such that V-shaped corrosion groove preferentially occurs at the seam weld.

S.J. Luo; R. Wang

2014-01-01T23:59:59.000Z

116

Characterization of microstructures and mechanical properties of Inconel 617/310 stainless steel dissimilar welds  

SciTech Connect (OSTI)

The microstructure and mechanical properties of Inconel 617/310 austenitic stainless steel dissimilar welds were investigated in this work. Three types of filler materials, Inconel 617, Inconel 82 and 310 austenitic stainless steels were used to obtain dissimilar joint using the gas tungsten arc welding process. Microstructural observations showed that there was no evidence of any possible cracking in the weldments achieved by the nickel-base filler materials. The welds produced by 617 and 310 filler materials displayed the highest and the lowest ultimate tensile strength and total elongation, respectively. The impact test results indicated that all specimens exhibited ductile fracture. Among the fillers, Inconel 617 exhibited superlative fracture toughness (205 J). The mechanical properties of the Inconel 617 filler material were much better than those of other fillers. - Research Highlights: {yields} A fine dendritic structure was seen for the Inconel 617 weld metal. {yields} A number of cracks were initiated when the 310 SS filler metal was used. {yields} All welded samples showed ductile fracture. {yields} The Inconel 617 filler material presents the optimum mechanical properties.

Shah Hosseini, H., E-mail: h.shahhosseini@ma.iut.ac.ir; Shamanian, M.; Kermanpur, A.

2011-04-15T23:59:59.000Z

117

Final Assessment of Manual Ultrasonic Examinations Applied to Detect Flaws in Primary System Dissimilar Metal Welds at North Anna Power Station  

SciTech Connect (OSTI)

PNNL conducted a technical assessment of the NDE issues and protocols that led to missed detections of several axially oriented flaws in a steam generator primary inlet dissimilar metal weld at North Anna Power Station, Unit 1 (NAPS-1). This particular component design exhibits a significant outside-diameter (OD) taper that is not included as a blind performance demonstration mock-up within the industry’s Performance Demonstration Initiative, administered by EPRI. For this reason, the licensee engaged EPRI to assist in the development of a technical justification to support the basis for a site-specific qualification. The service-induced flaws at NAPS-1 were eventually detected as a result of OD surface machining in preparation for a full structural weld overlay. The machining operation uncovered the existence of two through-wall flaws, based on the observance of primary water leaking from the dissimilar metal weld. A total of five axially oriented flaws were detected in varied locations around the weld circumference. The field volumetric examination that was conducted at NAPS-1 was a non-encoded, real-time manual ultrasonic examination. PNNL conducted both an initial assessment, and subsequently, a more rigorous technical evaluation (reported here), which has identified an array of NDE issues that may have led to the subject missed detections. These evaluations were performed through technical reviews and discussions with NRC staff, EPRI NDE Center personnel, industry and ISI vendor personnel, and ultrasonic transducer manufacturers, and laboratory tests, to better understand the underlying issues at North Anna.

Anderson, Michael T.; Diaz, Aaron A.; Cinson, Anthony D.; Crawford, Susan L.; Prowant, Matthew S.; Doctor, Steven R.

2014-03-24T23:59:59.000Z

118

Effect of metal oxide and oxygen on the growth of single-walled carbon nanotubes by electric arc discharge  

Science Journals Connector (OSTI)

The effect of oxygen on the growth of single-walled carbon nanotubes was studied with Ni–Co alloy powder as catalyst under helium atmosphere of 500 Torr by electric arc discharge. The oxygen included in nickel or...

Delong He; Yongning Liu; Tingkai Zhao; Jiewu Zhu…

2008-03-01T23:59:59.000Z

119

Weld seam tracking and lap weld penetration monitoring using the optical spectrum of the weld plume  

SciTech Connect (OSTI)

Joining of dissimilar materials is a long standing problem in manufacturing, with many tricks and special techniques developed to successfully join specific pairs of materials. Often, these special techniques impose stringent requirements on the process such as precise control of process parameters to achieve the desired joint characteristics. Laser welding is one of the techniques which has had some success in welding dissimilar metal alloys, and appears to be a viable process for these materials. Minimal heat input limits differential thermal expansion, and the small weld pool allows precise control of alloy mixing in the fusion zone. Obtaining optimal weld performance requires accurate monitoring and control of absorbed laser power and weld focus position. In order to monitor the laser welding process, the authors have used a small computer controlled optical spectrometer to observe the emission from the weld plume. Absorbed laser power can be related to the temperature of the weld pool surface and the plume above the weld. Focus position relative to the joint can easily be seen by the proportion of elements from each material existing in the plume. This monitor has been used to observe and optimize the performance of butt and lap welds between dissimilar alloys, where each alloy contains at least one element not found in the other alloy. Results will be presented for a copper-steel butt joint and a lap weld between stainless and low alloy steels.

Mueller, R.E. [Univ. of Waterloo, Ontario (Canada); Hopkins, J.A.; Semak, V.V.; McCay, M.H. [Univ. of Tennessee, Tullahoma, TN (United States)

1996-12-31T23:59:59.000Z

120

Effect of the surface preparation techniques on the EBSD analysis of a friction stir welded AA1100-B{sub 4}C metal matrix composite  

SciTech Connect (OSTI)

Aluminum based metal matrix composites (MMCs) have been used in various automobile, aerospace and military industries. Yet characterization of the microstructure in these materials remains a challenge. In the present work, the grain structure in the matrix of B{sub 4}C particulate reinforced MMCs and their friction stir welds is characterized by using optical metallography and the electron backscatter diffraction (EBSD) technique. Optical metallography can partially reveal the grain structure in the matrix of AA1100-16 vol.% B{sub 4}C composite. The EBSD technique has been successfully applied to characterize the grain structure in the AA1100-16 vol.% B{sub 4}C friction stir welds, which provides a powerful tool to follow the microstructural evolution of MMC materials during friction stir welding (FSW). Both mechanical polishing and ion beam polishing are used for the EBSD sample preparation. The effect of the sample preparation on the EBSD data acquisition quality is studied. Some typical examples, such as the identification of grains and subgrains, grain size distribution, deformation fields and the texture components are given. - Highlights: {yields} EBSD has been used to characterize the grain structure of Al-B{sub 4}C MMCs. {yields} Mechanical and ion beam polishing are compared for EBSD sample preparation of MMCs. {yields} EBSD shows great advantages over optical microscopy for microtexture analysis of MMCs.

Guo, J., E-mail: junfeng.guo@cnrc-nrc.gc.ca [University of Quebec at Chicoutimi, Chicoutimi (QC), G7H 2B1 (Canada); Aluminium Technology Centre, National Research Council Canada, Chicoutimi (QC), G7H 8C3 (Canada); Amira, S.; Gougeon, P. [Aluminium Technology Centre, National Research Council Canada, Chicoutimi (QC), G7H 8C3 (Canada); Chen, X.-G. [University of Quebec at Chicoutimi, Chicoutimi (QC), G7H 2B1 (Canada)

2011-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Weld Monitor  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Monitoring of Laser Beam Welding Monitoring of Laser Beam Welding Using Infrared Weld Emissions P. G. Sanders, J. S. Keske, G. Kornecki, and K. H. Leong Technology Development Division Argonne National Laboratory Argonne, IL 60439 USA The submitted manuscript has been authorized by a contractor of the U. S. Government under contract No. W-31-109-ENG-38. Accordingly, the U. S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or allow others to do so, for U. S. Government purposes. Abstract A non-obtrusive, pre-aligned, solid-state device has been developed to monitor the primary infrared emissions during laser welding. The weld monitor output is a 100-1000 mV signal that depends on the beam power and weld characteristics. The DC level of this signal is related to weld

122

Refractory Alloy Welding [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Refractory Alloy Welding Refractory Alloy Welding Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Refractory Alloy Welding Project description: Welding of refractory metals such as vanadium alloys. Category: internal R&D project Bookmark and Share Butt weld of two 4 mm thick V-4Cr-4Ti plates made by a pulsed Nd:YAG laser

123

A New Type of Submerged-Arc Flux-Cored Wire Used for Hardfacing Continuous Casting Rolls  

Science Journals Connector (OSTI)

It is expected that the welding hardfacing of continuous casting rolls has better welding performance and higher wear resistance. A new type of submerged-arc hardfacing flux-cored wire has been developed through nitrogen replacing part of carbon and addition of the nitrogen-fixing elements of niobium and titanium. And microstructure, degree of hardness and high-temperature wear resistance of its deposited metal samples were also investigated. It is found that the microstructure is martensite, residual austenite and carbonitride precipitates. As a result, the hardfacing metal with homogeneous distribution of very fine carbonitride particles had high hardness and excellent wear-resisting property during high-temperature wear, which could significantly extend the service life of continuous casting rolls.

Ke YANG; Zhi-xi ZHANG; Wang-qin HU; Ye-feng BAO; Yong-feng JIANG

2011-01-01T23:59:59.000Z

124

Technical Letter Report, An Evaluation of Ultrasonic Phased Array Testing for Reactor Piping System Components Containing Dissimilar Metal Welds, JCN N6398, Task 2A  

SciTech Connect (OSTI)

Research is being conducted for the U.S. Nuclear Regulatory Commission at the Pacific Northwest National Laboratory to assess the effectiveness and reliability of advanced nondestructive examination (NDE) methods for the inspection of light-water reactor components. The scope of this research encom¬passes primary system pressure boundary materials including dissimilar metal welds (DMWs), cast austenitic stainless steels (CASS), piping with corrosion-resistant cladding, weld overlays, inlays and onlays, and far-side examinations of austenitic piping welds. A primary objective of this work is to evaluate various NDE methods to assess their ability to detect, localize, and size cracks in steel components that challenge standard and/or conventional inspection methodologies. This interim technical letter report provides a summary of a technical evaluation aimed at assessing the capabilities of phased-array (PA) ultrasonic testing (UT) methods as applied to the inspection of small-bore DMW components that exist in the reactor coolant systems (RCS) of pressurized water reactors (PWRs). Operating experience and events such as the circumferential cracking in the reactor vessel nozzle-to-RCS hot leg pipe at V.C. Summer nuclear power station, identified in 2000, show that in PWRs where primary coolant water (or steam) are present under normal operation, Alloy 82/182 materials are susceptible to pressurized water stress corrosion cracking. The extent and number of occurrences of DMW cracking in nuclear power plants (domestically and internationally) indicate the necessity for reliable and effective inspection techniques. The work described herein was performed to provide insights for evaluating the utility of advanced NDE approaches for the inspection of DMW components such as a pressurizer surge nozzle DMW, a shutdown cooling pipe DMW, and a ferritic (low-alloy carbon steel)-to-CASS pipe DMW configuration.

Diaz, Aaron A.; Cinson, Anthony D.; Crawford, Susan L.; Anderson, Michael T.

2009-11-30T23:59:59.000Z

125

Development of steel plate and welding material with superior preferential corrosion resistance in welded joint  

SciTech Connect (OSTI)

The effects of chemical composition and microstructure on preferential corrosion of YP 420MPa steel were investigated. The test results indicated that the Ni addition prevented preferential corrosion in weld metal and heat affected zone (HAZ). The high contents of C and Cy accelerated preferential corrosion in HAZ. Inhibition of the creation of M-A constituents was effective in preventing the localized corrosion in HAZ. The localized corrosion in the welded joint was prevented by increasing the rest potential of weld metal by adding of Cr or Ni to the weld metal.

Kimura, Mitsuo; Miyata, Yukio; Saito, Yoshiyuki; Nakano, Yoshifumi [Kawasaki Steel Corp., Chiba (Japan)

1994-12-31T23:59:59.000Z

126

Evaluation of a portable x-ray fluorescence survey meter for the quantitative determination of trace metals in welding fumes  

E-Print Network [OSTI]

of Radioisotope Sources Utilized II. Results of Sensitivity Determination III. Long-tenn Instrumental Variability IV. Short-term Instrumental Variability V. Instrumental Variability Due to Temperature Fluctuations Vl. Average 948ias for Each Element VII.... Average %Bias for Each Sample 46 47 48 49 52 INTRCUUCTI Gbl The analysis of the elemental composition of welding fumes is often done in indust, rial hygiene work, as the fumes generated are toxic in many cases. However, the standard analytical...

Fehrenbacher, Mary Catherine

1984-01-01T23:59:59.000Z

127

F i W ldiFusion Welding ME 4210: Manufacturing Processes and Engineering  

E-Print Network [OSTI]

-fuel) cutting · Thermit Electric arc· Electric arc · Resistance L b· Laser beam · Electron beam ME 4210 Welding ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2009 11 #12;Electric ArcElectric solid rocket booster (SRB) · In skin of Hindenburg dirigible ­ electrostatic discharge caused fire ME

Colton, Jonathan S.

128

Welding and Weldability of Thorium-Doped Iridium Alloys  

SciTech Connect (OSTI)

Ir-0.3%W alloys doped with thorium are currently used as post-impact containment material for radioactive fuel in thermoelectric generators that provide stable electrical power for a variety of outer planetary space exploration missions. Welding and weldability of a series of alloys was investigated using arc and laser welding processes. Some of these alloys are prone to severe hot-cracking during welding. Weldability of these alloys was characterized using Sigmajig weldability test. Hot-cracking is influenced to a great extent by the fusion zone microstructure and composition. Thorium content and welding atmosphere were found to be very critical. The weld cracking behavior in these alloys can be controlled by modifying the fusion zone microstructure. Fusion zone microstructure was found to be controlled by welding process, process parameters, and the weld pool shape.

David, S.A.; Ohriner, E.K.; King, J.F.

2000-03-12T23:59:59.000Z

129

Characteristics of the weld interface in dissimilar austenitic-pearlitic steel welds  

SciTech Connect (OSTI)

The weld interface in dissimilar alloy welds between austenitic and pearlitic steels was observed directly by using scanning and transmission electron microscopy, and energy-dispersive x-ray spectrometry. Two types of weld interface were found in the joints. One was the austenite/martensite-like interface that formed the boundary between the mixed weld metal zone and the partially mixed transitional zone. The other is the martensite-like/ferrite interface that is the true liquid-solid boundary of the joint. These interfaces can exist independently in different joints and can also coexist in one joint, depending on the Cr and Ni contents of the filler metals and alloy in the base metals. The formation mechanism of the weld interface and its effect on the mechanical properties of the welded joint are discussed.

Pan, C.; Zhang, Z. (Wuhan Transportation Univ. (China). Dept. of Marine Mechanical Engineering)

1994-09-01T23:59:59.000Z

130

Prediction of Weld Penetration in FCAW of HSLA steel using Artificial Neural Networks  

SciTech Connect (OSTI)

Flux-cored arc welding (FCAW) is a semiautomatic or automatic arc welding process that requires a continuously-fed consumable tubular electrode containing a flux. The main FCAW process parameters affecting the depth of penetration are welding current, arc voltage, nozzle-to-work distance, torch angle and welding speed. Shallow depth of penetration may contribute to failure of a welded structure since penetration determines the stress-carrying capacity of a welded joint. To avoid such occurrences; the welding process parameters influencing the weld penetration must be properly selected to obtain an acceptable weld penetration and hence a high quality joint. Artificial neural networks (ANN), also called neural networks (NN), are computational models used to express complex non-linear relationships between input and output data. In this paper, artificial neural network (ANN) method is used to predict the effects of welding current, arc voltage, nozzle-to-work distance, torch angle and welding speed on weld penetration depth in gas shielded FCAW of a grade of high strength low alloy steel. 32 experimental runs were carried out using the bead-on-plate welding technique. Weld penetrations were measured and on the basis of these 32 sets of experimental data, a feed-forward back-propagation neural network was created. 28 sets of the experiments were used as the training data and the remaining 4 sets were used for the testing phase of the network. The ANN has one hidden layer with eight neurons and is trained after 840 iterations. The comparison between the experimental results and ANN results showed that the trained network could predict the effects of the FCAW process parameters on weld penetration adequately.

Asl, Y. Dadgar; Mostafa, N. B.; Panahizadeh, V. R. [Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran (Iran, Islamic Republic of); Seyedkashi, S. M. H. [Department of Mechanical Engineering, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

2011-01-17T23:59:59.000Z

131

Anode and Cathode Arcs  

Science Journals Connector (OSTI)

... we call an anode arc, produces a circular pit on the anode and a general roughening of the opposed cathode. Photomicrographs of single anode-type arcs were published1 before the ... arcs\tCathode arcs

L. H. GERMER; W. S. BOYLE

1955-11-26T23:59:59.000Z

132

S&TR | March/April 2008: Standardizing the Art of Electron-Beam Welding  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Standardizing the Art of Electron-Beam Welding. Standardizing the Art of Electron-Beam Welding. WELDED materials are an integral part of everyday life. Appliances, cars, and bridges are all made by welding materials together. But not all welds are created equal. Welding methods vary in complexity, time, and cost, depending on a product's requirements and purpose. In electron-beam (EBeam) welding, an electron beam generated in a vacuum creates a fusing heat source that can unite almost any metals. This method produces deep welds without adding excessive heat that can adversely affect the properties of the surrounding metal. In the nuclear energy and aerospace industries, electron-beam welding is preferred for manufacturing high-value welds-those in which defects cannot be tolerated. The Department of Energy's (DOE's) nuclear weapons

133

Research on micro-electric resistance slip welding of copper electrode during the fabrication of 3D metal micro-mold  

Science Journals Connector (OSTI)

Abstract 3D micro-mold fabricated by the micro double-staged laminated object manufacturing process (micro-DLOM) is formed via stacking and fitting of multi-layer 2D micro-structures. The connection of 2D micro-structures is related to forming accuracy and mechanical properties of 3D micro-mold. In this research, micro-electric resistance slip welding of copper electrodes was proposed to connect multi-layer 2D micro-structures. Firstly, the proper process parameters of slip welding were obtained through the welding experiment, and the temperature field of micro-electric resistance slip welding under such process parameters was simulated. Secondly, deposition effect of the copper bar electrode produced during slip welding was studied and the study results show that the copper element deposited in the slip welding area decreases as the surface roughness of copper electrode decreases. Finally, based on the above research, a square micro-cavity mold with micro-channel, a circular micro-cavity mold with cross keyway and micro gear cavity mold with two-stage steps were welded by the micro-electric resistance slip welding.

Bin Xu; Xiao-yu Wu; Jian-guo Lei; Feng Luo; Feng Gong; Chen-lin Du; Xiu-quan Sun; Shuang-chen Ruan

2013-01-01T23:59:59.000Z

134

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables. 34 figs.

Milewski, J.O.; Sklar, E.

1998-06-02T23:59:59.000Z

135

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables.

Milewski, John O. (Santa Fe, NM); Sklar, Edward (Santa Fe, NM)

1998-01-01T23:59:59.000Z

136

Dissimilar-alloy laser welding of titanium: Ti6Al-4V to Beta-C{trademark}  

SciTech Connect (OSTI)

Beta-C{sup TM} is a metastable-beta titanium alloy (nominal composition: Ti-3wt%Al-8wt%V-6wtTCr-4wt%Mo-4wt%Zr) which can be thermomechanically processed and heat treated to provide excellent combinations of strength, ductility, and fracture toughness. Recently, the increased application of metastable-beta titanium alloys in aerospace and commercial applications has resulted in the necessity to join these alloys to conventional alpha-beta titanium alloys. Based on this previous work, two approaches were considered for improving the ductility of dissimilar-alloy welds between Ti-6Al-4V and Beta-C{sup TM} in the present study: (1) application of a low heat input welding process to minimize the fusion zone and heat-affected zone (HAZ) beta grain size and (2) modification of the fusion zone chemical composition to allow greater microstructural optimization through postweld aging. CO{sub 2} laser welds were produced between Ti-6Al-4V and Beta-C{sup TM} sheet. Three different nominal fusion zone chemical compositions were obtained by varying the laser beam locations relative to the joint centerline and thereby melting different quantities of each base metal. For comparable postweld aging conditions, the laser welds exhibited ductilities superior to those of coarse-grained gas tungsten arc welds. Fracture analysis of the weld zone revealed a transition from a predominantly transgranular fracture in the low-temperature aged conditions to increasingly intergranular fracture following aging at higher temperature. This transition was promoted by an increase in the thickness and continuity of alpha phase at beta grain boundaries.

Liu, P.S.; Baeslack, W.A. III; Hurley, J.

1994-12-31T23:59:59.000Z

137

Effect of soft root weld layer on fracture toughness of under-matched weld joints on Q+T steel  

SciTech Connect (OSTI)

Welding of quenched and tempered (Q+T) high strength low alloyed steels can cause weld strength undermatching to satisfy the toughness requirements for the weld deposit. Cost of pre-heating of these steels can be saved if one can prove that use of soft electrodes for root passes do not endanger the overall quality of the joint. By welding of 40 mm thick Q+T structural steel (grade HT 80), over-matched condition had appeared in the root area of the X-groove weld despite of welding consumable which would give entire weld under-matched properties. This is the effect of weld metal alloying by elements from base material. So, the weld joint is not protected against cold cracking especially in the root region, therefore, a high preheating should be used to reduce the possibility of this phenomenon. In this work soft (lower strength) filler metal was used for first two and four root passes of X-joint. In this case root area was also alloyed by elements from base material and obtained mis-matching factor M was higher than it was expected. So, one homogeneous and two non homogeneous weld joints (with two and four soft passes) were considered. Mechanical properties of weld joints were measured by round tensile bars taken from different parts of the weld. The under-matching factor of weld joint with two and four soft root passes was around 0.80--0.90 in the soft root layer. It was expected that uneven strength distribution along the fatigue crack tip line would affect fracture initiation behavior of all three different weld joints. The metallographical post-test sectioning has revealed the initiation points mainly at the lowest weld metal strength.

Rak, I.; Gliha, V.; Praunseis, Z. [Univ. of Maribor (Slovenia). Faculty of Mechanical Engineering; Kocak, M. [GKSS Research Center, Geesthacht (Germany). Inst. of Material Research

1996-12-01T23:59:59.000Z

138

Initial Development in Joining of ODS Alloys Using Friction Stir Welding  

SciTech Connect (OSTI)

Solid-state welding of oxide-dispersion-strengthened (ODS) alloy MA956 sheets using friction stir welding (FSW) was investigated. Butt weld was successfully produced. The weld and base metals were characterized using optical microscopy, scanning electronic microscopy, transmission electronic microscopy, and energy dispersion x-ray spectrum. Microhardness mapping was also conducted over the weld region. Analyses indicate that the distribution of the strengthening oxides was preserved in the weld. Decrease in microhardness of the weld was observed but was insignificant. The preliminary results seem to confirm the envisioned feasibility of FSW application to ODS alloy joining. For application to Gen IV nuclear reactor heat exchanger, further investigation is suggested.

Ren, Weiju [ORNL; Feng, Zhili [ORNL

2007-08-01T23:59:59.000Z

139

Description of the Gas-Metal-Laser Interaction Phenomena. The Importance of the Shielding Gases in High Power (Multikilowatt) CO2 Laser Welding  

Science Journals Connector (OSTI)

CO2 LASER welding is not yet a commonly used process. However, it has some advantages among which the most important seem to be: small distortion and heat affected zone, high productivity and flexibility (it is e...

Marchand Didier

1992-01-01T23:59:59.000Z

140

PROCEDURES FOR ARC PROJECTS  

E-Print Network [OSTI]

PROCEDURES FOR ARC PROJECTS Revised - May 2013 Agricultural Research Center Washington State University #12;Table of Contents THE PROJECT SYSTEM, AN INTRODUCTION................................................................................. 5 DEVELOPING AN ARC PROJECT

Collins, Gary S.

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Field Evaluations of Low-Frequency SAFT-UT on Cast Stainless Steel and Dissimilar Metal Weld Components  

SciTech Connect (OSTI)

This report documents work performed at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, and at the Electric Power Research Institute's (EPRI) Nondestructive Examination (NDE) Center in Charlotte, North Carolina, on evalutating a low frequency ultrasonic inspection technique used for examination of cast stainless steel (CSS) and dissimilar metal (DMW) reactor piping components. The technique uses a zone-focused, multi-incident angle, low frequency (250-450 kHz) inspection protocol coupled with the synthetic aperture focusing technique (SAFT). The primary focus of this work is to provide information to the United States Nuclear Regulatory Commission on the utility, effectiveness and reliability of ultrasonic testing (UT) inspection techniques as related to the inservice ultrasonic inspection of coarse grained primary piping components in pressurized water reactors (PWRs).

Diaz, Aaron A.; Harris, R. V.; Doctor, Steven R.

2008-11-01T23:59:59.000Z

142

Corrosion-fatigue crack growth behavior of surface crack on AH36 TMCP steel weld in seawater  

SciTech Connect (OSTI)

Fatigue crack growth behavior in seawater of surface crack on the weld was studied with a structural steel, AH36, manufactured by the thermo-mechanical control process (TMCP). Crack growth rate was measured for the surface cracks located in different regions of weld, such as the heat affected zone, the weld metal and the base metal. Influence of the welding condition was investigated with the variation of heat inputs of 80, 120 and 180 kJ/cm. Electrochemical analysis of each region of the weld was also performed to investigate the corrosion behavior between the weld and the base metal.

Kweon, Y.G.; Jeong, H.D.; Chang, R.W. [Research Inst. of Industrial Science and Technology, Pohang (Korea, Republic of). Welding Research Center

1995-12-31T23:59:59.000Z

143

Seal welded cast iron nuclear waste container  

DOE Patents [OSTI]

This invention identifies methods and articles designed to circumvent metallurgical problems associated with hermetically closing an all cast iron nuclear waste package by welding. It involves welding nickel-carbon alloy inserts which are bonded to the mating plug and main body components of the package. The welding inserts might be bonded in place during casting of the package components. When the waste package closure weld is made, the most severe thermal effects of the process are restricted to the nickel-carbon insert material which is far better able to accommodate them than is cast iron. Use of nickel-carbon weld inserts should eliminate any need for pre-weld and post-weld heat treatments which are a problem to apply to nuclear waste packages. Although the waste package closure weld approach described results in a dissimilar metal combination, the relative surface area of nickel-to-iron, their electrochemical relationship, and the presence of graphite in both materials will act to prevent any galvanic corrosion problem.

Filippi, Arthur M. (Pittsburgh, PA); Sprecace, Richard P. (Murrysville, PA)

1987-01-01T23:59:59.000Z

144

Unipolar arc simulation device  

SciTech Connect (OSTI)

We describe a simple laboratory device for establishing a vacuum arc plasma discharge that can serve to simulate a unipolar arc. The technique makes use of a triggered vacuum arc plasma gun to generate a plasma plume that in turn causes breakdown of a secondary discharge. The device is in fact a secondary vacuum arc discharge that is triggered by a primary vacuum arc discharge, with some of the features of the secondary plasma discharge having similarities with a unipolar arc configuration. Here we describe the experimental setup and outline how the device can be used for some areas of unipolar arc materials research. [copyright] [ital 1999 American Institute of Physics.

Wang, S.G.; Brown, I.G. (Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 (United States))

1999-09-01T23:59:59.000Z

145

Weld solidification cracking in 304 to 304L stainless steel  

SciTech Connect (OSTI)

A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found. This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GT A W showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Martinez, Raymond J [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

146

Weld solidification cracking in 304 to 204L stainless steel  

SciTech Connect (OSTI)

A series of annulus welds were made between 304 and 304L stainless steel coaxial tubes using both pulsed laser beam welding (LBW) and pulsed gas tungsten arc welding (GTAW). In this application, a change in process from pulsed LBW to pulsed gas tungsten arc welding was proposed to limit the possibility of weld solidification cracking since weldability diagrams developed for GTAW display a greater range of compositions that are not crack susceptible relative to those developed for pulsed LBW. Contrary to the predictions of the GTAW weldability diagram, cracking was found.This result was rationalized in terms of the more rapid solidification rate of the pulsed gas tungsten arc welds. In addition, for the pulsed LBW conditions, the material compositions were predicted to be, by themselves, 'weldable' according to the pulsed LBW weldability diagram. However, the composition range along the tie line connecting the two compositions passed through the crack susceptible range. Microstructurally, the primary solidification mode (PSM) of the material processed with higher power LBW was determined to be austenite (A), while solidification mode of the materials processed with lower power LBW apparently exhibited a dual PSM of both austenite (A) and ferrite-austenite (FA) within the same weld. The materials processed by pulsed GTAW showed mostly primary austenite solidification, with some regions of either primary austenite-second phase ferrite (AF) solidification or primary ferrite-second phase austenite (FA) solidification. This work demonstrates that variations in crack susceptibility may be realized when welding different heats of 'weldable' materials together, and that slight variations in processing can also contribute to crack susceptibility.

Hochanadel, Patrick W [Los Alamos National Laboratory; Lienert, Thomas J [Los Alamos National Laboratory; Martinez, Jesse N [Los Alamos National Laboratory; Johnson, Matthew Q [Los Alamos National Laboratory

2010-09-15T23:59:59.000Z

147

The influence of position in overlap joints of Mg and Al alloys on microstructure and hardness of laser welds.  

E-Print Network [OSTI]

assembly. Therefore, the dissimilar-metal welding process has been identified as top priority for materials and resistance of this combination, and lead to the formation of intermetallic compounds in the welded metal. Keywords: laser welding, dissimilar materials, AZ31 magnesium alloy, A5754 aluminum alloy, microstructure

Paris-Sud XI, Université de

148

Evaluation of weld porosity in laser beam seam welds: optimizing continuous wave and square wave modulated processes.  

SciTech Connect (OSTI)

Nd:YAG laser joining is a high energy density (HED) process that can produce high-speed, low-heat input welds with a high depth-to-width aspect ratio. This is optimized by formation of a ''keyhole'' in the weld pool resulting from high vapor pressures associated with laser interaction with the metallic substrate. It is generally accepted that pores form in HED welds due to the instability and frequent collapse of the keyhole. In order to maintain an open keyhole, weld pool forces must be balanced such that vapor pressure and weld pool inertia forces are in equilibrium. Travel speed and laser beam power largely control the way these forces are balanced, as well as welding mode (Continuous Wave or Square Wave) and shielding gas type. A study into the phenomenon of weld pool porosity in 304L stainless steel was conducted to better understand and predict how welding parameters impact the weld pool dynamics that lead to pore formation. This work is intended to aid in development and verification of a finite element computer model of weld pool fluid flow dynamics being developed in parallel efforts and assist in weld development activities for the W76 and future RRW programs.

Ellison, Chad M. (Honeywell FM& T, Kansas City, MO); Perricone, Matthew; Faraone, Kevin M. (Honeywell FM& T, Kansas City, MO); Roach, Robert Allen; Norris, Jerome T.

2007-02-01T23:59:59.000Z

149

Fusion welding process  

DOE Patents [OSTI]

A process for the fusion welding of nickel alloy steel members wherein a ferrite containing pellet is inserted into a cavity in one member and melted by a welding torch. The resulting weld nugget, a fusion of the nickel containing alloy from the members to be welded and the pellet, has a composition which is sufficiently low in nickel content such that ferrite phases occur within the weld nugget, resulting in improved weld properties. The steel alloys encompassed also include alloys containing carbon and manganese, considered nickel equivalents.

Thomas, Kenneth C. (Export, PA); Jones, Eric D. (Salem, PA); McBride, Marvin A. (Hempfield Township, Westmoreland County, PA)

1983-01-01T23:59:59.000Z

150

UT of bimetallic welds by shear horizontal waves and electromagnetic ultrasonic (EMUS) probes  

SciTech Connect (OSTI)

Bimetallic transition welds include in most cases besides the austenitic weldment an austenitic buttering. Their inspection by ultrasound is strongly complicated by a high degree of elastic anisotropy. The elastic anisotropy results in phase and group velocities of the elastic wave-modes, which are functions of the propagation direction inside the weld metal and which cause skewing of the sound beams. The coarse grain structure leads to enhanced scattering. Furthermore, there exists a mismatch of the acoustical impedances between the weld metal and the base metal, which depends on the angle of incidence at the interface base metal/weld metal and weld metal/buttering. Due to these facts up to now using standard UT-techniques only the HAZ`s are inspected from both sides. In many cases dissimilar metal welds are only accessible from one side. Therefore, US-techniques are necessary which are capable to inspect the whole weld even if there is only access from one side. By improvement of the technology of the EMUS-probes and of the EMUS-instrumentation for the US-transduction of SH-waves a reliable technique for the ISI of dissimilar metal welds and also of austenitic welds is available. The contribution will shortly introduce into the physical basis of the SH-wave technique and present the results of test specimen measurements. The main part of the paper will report about the experiences and the results of field applications in different nuclear power plants.

Huebschen, G.; Salzburger, H.J.; Kroening, M. [Fraunhofer-Inst. fuer Zerstoerungsfreie Pruefverfahren, Saarbruecken (Germany)

1994-12-31T23:59:59.000Z

151

CRAD, Welding, Cutting and Brazing Assessment Plan  

Broader source: Energy.gov [DOE]

This assessment is to verify hot work requirements associated with welding, cutting, burning, brazing, grinding and other spark- or flame-producing operations have been implemented. Verify that the requirements implemented are appropriate for preventing loss of life and property from fire, and personal injury from contact with or exposure to molten metals, vapors, radiant energy, injurious rays and sparks.

152

Effective dose in the manufacturing process of rutile covered welding electrodes  

Science Journals Connector (OSTI)

Shielded metal arc welding using covered electrodes is the most common welding process. Sometimes the covering contains naturally occurring radioactive materials (NORMs). In Spain the most used electrodes are those covered with rutile mixed with other materials. Rutile contains some detectable natural radionuclides, so it can be considered a NORM. This paper mainly focuses on the use of MCNP (Monte Carlo N-Particle Transport Code) as a predictive tool to obtain doses in a factory which produces this type of electrode and assess the radiological impact in a specific facility after estimating the internal dose.To do this, in the facility, areas of highest radiation and positions of workers were identified, radioactive content of rutile and rutile covered electrodes was measured, and, considering a worst possible scenario, external dose at working points has been calculated using MCNP. This procedure has been validated comparing the results obtained with those from a pressurised ionisation chamber and TLD dosimeters. The internal dose has been calculated using DCAL (dose and risk calculation). The doses range between 8.8 and 394 ?Sv yr?1, always lower than the effective dose limit for the public, 1 mSv yr?1. The highest dose corresponds to the mixing area.

M Herranz; S Rozas; C Pérez; R Idoeta; R Núñez-Lagos; F Legarda

2013-01-01T23:59:59.000Z

153

Spot welding of steel and aluminum using insert sheet  

SciTech Connect (OSTI)

Automobile industries have been increasingly interested in the use of aluminum and thus joining of steel and aluminum becomes of importance. The joining of the two types of metal raises a problem of brittle welds caused by the formation of intermetallic compounds. The authors solved the problem by using an insert sheet. This paper deals with the resistance spot welding of steel and aluminum sheets using insert sheets. The insert sheet used in the present development was a steel/aluminum clad sheet of the 0.8 mm thickness with 50% steel and 50% aluminum. The clad sheet was produced by warm rolling of steel and aluminum with a direct resistance heating process. Steel to be warm rolled was of EDDQ of the 0.4 mm thickness and aluminum was of JIS A1050 of 0.6 mm thickness. The mechanical properties of the insert clad sheets were in between those of the steel sheets and the aluminum sheets, while the clad sheets showed much better formability than the aluminum sheets. Resistance spot welding was conducted for 0.8 mm thick EDDQ steel sheets and 1.0 mm thick aluminum alloy (AL-5.5%Mg) sheets under the welding force of 1.96 kN, welding current ranging between 4.2 and 20.1 kA, and welding time from 0.5 to 10 cycles. The steel was spot welded to the steel side of the insert sheet while the aluminum was welded to the aluminum side. What the authors investigated were the applicable welding current range, nugget diameter, tensile shear strength, U-tension strength, and macro- and microstructures. In conclusion, steel sheets can be spot welded to aluminum sheets without difficulty by using clad sheets as insert materials while the strength level of the dissimilar metal spot welds is close to that of aluminum joints.

Oikawa, H.; Saito, T.; Yoshimura, T. [and others

1994-12-31T23:59:59.000Z

154

Taupo's atypical arc  

Science Journals Connector (OSTI)

... many other continental arcs around the world, with andesite-dacite cone volcaaoes and relatively low geothermal heat fluxes. In sharp contrast, in the middle

Colin J. N. Wilson

1996-01-04T23:59:59.000Z

155

On-Line Weld NDE with IR Thermography  

Broader source: Energy.gov (indexed) [DOE]

advisory committee in the order of importance (high to low) - Weld with no or minimal fusion - Cold or stuck weld - Weld nugget size - Weld expulsion and indentation - Weld...

156

CRAD, Welding, Cutting and Brazing Assessment Plan | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Welding, Cutting and Brazing Assessment Plan Welding, Cutting and Brazing Assessment Plan CRAD, Welding, Cutting and Brazing Assessment Plan Performance Objective: This assessment is to verify hot work requirements associated with welding, cutting, burning, brazing, grinding and other spark- or flame-producing operations have been implemented. Verify that the requirements implemented are appropriate for preventing loss of life and property from fire, and personal injury from contact with or exposure to molten metals, vapors, radiant energy, injurious rays and sparks. Criteria: Establish designated area in which routine and repetitive welding, cutting, and other spark- or flame producing operations are conducted [1910.252(a)(2)(iv),1910.252(a)(2)(vi)(A), 1910.252(a)(2)(xv), General Requirements].

157

Residual Stress Determination for A Ferritic Steel Weld Plate  

SciTech Connect (OSTI)

The primary objective of this experiment is to demonstrate the capability of neutron diffraction technique to reproducibly map residual strains in a ferritic steel weld. The objective includes the identification of corrections for variations in metal composition due to the welding process which produces changes in lattice parameter that are not due to mechanical effects. The second objective is to develop and demonstrate a best practice for neutron diffraction strain mapping of steel welds. The appropriate coordinate system for the measurement of a weld, which is strongly distorted from planar geometry, has to be defined. The coordinate system is important in determining the procedures for mounting and positioning of the weld so that mapping details, especially in regions of high gradients, can be conveniently inter-compared between laboratories.

Wang, D.-Q.; Hubbard, C.R.; Spooner, S.

1999-10-01T23:59:59.000Z

158

Cathodic Arc Plasma Deposition  

Office of Scientific and Technical Information (OSTI)

Cathodic Arc Plasma Deposition Cathodic Arc Plasma Deposition André Anders Lawrence Berkeley National Laboratory, University of California, 1 Cyclotron Road, Mailstop 53, Berkeley, California 94720 aanders@lbl.gov Abstract Cathodic arc plasma deposition is one of oldest coatings technologies. Over the last two decades it has become the technology of choice for hard, wear resistant coatings on cutting and forming tools, corrosion resistant and decorative coatings on door knobs, shower heads, jewelry, and many other substrates. The history, basic physics of cathodic arc operation, the infamous macroparticle problem and common filter solutions are reviewed. Cathodic arc plasmas stand out due to their high degree of ionization, with important consequences for film nucleation, growth, and efficient utilization of substrate bias. The

159

Marangoni effects in welding  

Science Journals Connector (OSTI)

...problem of it variable weld penetration or cast-to-cast variation...etration in HS casts and reduced penetration in LS casts. Although this...travel speed (Sw) affects the rate of heat input to the weld...energy resulted in increased penetration for HS and MS casts but have...

1998-01-01T23:59:59.000Z

160

Electric arc saw apparatus  

DOE Patents [OSTI]

A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

Deichelbohrer, Paul R [Richland, WA

1986-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Dissimilar friction welding of titanium alloys to alloy 718  

SciTech Connect (OSTI)

The design of advanced, high-performance gas-turbine engines will require the utilization of elevated-temperature titanium-based materials, including conventional alloys, titanium aluminides, and titanium metal-matrix composites. The most efficient utilization of these materials in the engine compressor section would be achieved by directly joining these materials to existing nickel-base superalloys, such as Alloy 718. To date, the dissimilar welding of titanium alloys to nickel-based alloys has not been common practice because intermetallic compounds form in the weld and cause embrittlement. Special welding techniques must be developed to inhibit this compound formation and to provide high strength welds. In this investigation, a friction welding process was developed for joining titanium alloys (Ti-6Al-2Sn-4Zr-2Mo and Ti-6Al-4V) to nickel-based superalloy Alloy 718. An interlayer system comprised of copper and niobium sheet layers was employed as a diffusion barrier and weld deformation enhancer. A postweld heat treatment (PWHT, 700{degrees}C for 20 min in vacuum) under axial pressure (Ksi) was used to improve the joint strength consistency. The following conclusions can be drawn from this investigation: (1) A friction welding technique has been developed for joining titanium alloys (Ti-6Al-2Sn-4Zr-2Mo and Ti-6Al-4V) to Alloy 718 using an interlayer system of niobium and copper. Joint strengths averaging approximately 50 Ksi were achieved. (2) Deformation was concentrated in the interlayers, especially the copper interlayer, during friction welding. Increased reduction in length (RIL) during friction welding resulted in a decrease in the interlayer thicknesses. (3) The EDS results showed that the niobium and copper interlayers prevent interdiffusion between the two parent metals, producing formation of detrimental phases.

Kuo, M.; Albright, C.E.; Baeslack, W.A. III

1994-12-31T23:59:59.000Z

162

Fracture behavior of surface cracked wide plates of high strength steel containing overmatched repair welds  

SciTech Connect (OSTI)

This paper presents the experimental results of tests conducted using surface cracked wide plates containing overmatched repair weld joints. The deformation and fracture characteristics of the repair welded wideplates notched at the original weld deposit, repair weld and HAZ regions are discussed. The aim of this work was to investigate the effects of strength mis-match and notch position on the fracture performance of such complex weldments. Furthermore, the predictions of crack driving force using the Engineering Treatment Model for mis-matched welds (ETM-MM) procedure was compared with the results of the wide plates containing semielliptical surface cracks. For this study, 1/2K weld joints were prepared on 30 nm thick pipeline steel X65 plates by using a SAW process, resulting in 50% overmatching. Repair was performed at the cap side of the original joint up to half depth of plate thickness with a GMA welding process under hyperbaric conditions, leading to 41% yield strength overmatching. In order to assess the fracture behavior of these welds, surface cracked (semielliptic defects) wide plates containing original and repair welds were tested in tension at {minus}10 C. The surface cracked wide plate tests results have confirmed that overmatched repair weld metal can exert a significant effect on the deformation and fracture behavior of the wide plates. Wide plates containing root cracks clearly showed a shielding effect of the overmatched repair weld since it prevented development of through thickness ligament yielding.

Junghans, E.; Kocak, M.; Schwalbe, K.H. [GKSS Research Center, Geesthacht (Germany). Inst. of Materials Research

1996-12-01T23:59:59.000Z

163

Miniaturized cathodic arc plasma source  

DOE Patents [OSTI]

A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

Anders, Andre (Albany, CA); MacGill, Robert A. (Richmond, CA)

2003-04-15T23:59:59.000Z

164

Proceedings of NAMRI/SME, Vol. 39, 2011 Strength and Microstructure of Laser Fusion Welded Ti-SS  

E-Print Network [OSTI]

] or with the aid of a non-reactive interlayer [3][4]. Dissimilar metal welding (DMW) of the bio The ability to efficiently create robust and reliable dissimilar metal joints has the potential to enable new functionalities and reduce the manufacturing costs of medical devices. The need for dissimilar material welds

Yao, Y. Lawrence

165

Electroreduction of Oxygen in Polymer Electrolyte Fuel Cells by Activated Carbon Coated Cobalt Nanocrystallites Produced by Electric Arc Discharge  

Science Journals Connector (OSTI)

Electroreduction of Oxygen in Polymer Electrolyte Fuel Cells by Activated Carbon Coated Cobalt Nanocrystallites Produced by Electric Arc Discharge ... A recent review of the encapsulation of rare earth and iron group metals (Fe, Co, Ni) using electric arc discharge has been published by Saito. ... Nanotubes have been observed after activation of catalytically inactive carbon-coated Co nanocrystallites generated by electric arc discharge. ...

G. Lalande; D. Guay; J. P. Dodelet; S. A. Majetich; M. E. McHenry

1997-03-18T23:59:59.000Z

166

Friction stir welding tool  

DOE Patents [OSTI]

A friction stir welding tool is described and which includes a shank portion; a shoulder portion which is releasably engageable with the shank portion; and a pin which is releasably engageable with the shoulder portion.

Tolle, Charles R. (Idaho Falls, ID); Clark, Denis E. (Idaho Falls, ID); Barnes, Timothy A. (Ammon, ID)

2008-04-15T23:59:59.000Z

167

CO{sub 2} laser beam welding of magnesium-based alloys  

SciTech Connect (OSTI)

Magnesium has gained increased attention in recent years as a structural metal--especially in the automotive industry--necessitating the development of welding techniques qualified for this new application. Lasers are known to be an excellent tool for joining metals. This paper presents results of recent investigations on the weldability of several cast and wrought magnesium-based alloys. Plates with a thickness of 2.5--8 mm were butt joint welded with and without filler metal using a 2.5-kW CO{sub 2} laser. The investigations showed that magnesium alloys can be easily laser welded in similar and dissimilar joints. The beam characteristics of the laser leads to small welds and a deep penetration depth. Crackfree welds exhibiting low porosity and good surface finish can be achieved with appropriate process parameters. Generally, the laser welding leads to either no change or a small increase in hardness in the fusion zone (FZ) and in the heat-affected zone (HAZ) relative to the base metal. Less promising results were obtained for the cast alloy QE22, in which cracking in the age-hardened condition and a significant decrease in hardness occurred. Laser welded die cast alloys showed an extremely high level of porosity in the weld.

Weisheit, A.; Galun, R.; Mordike, B.L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Werkstoffkunde und Werkstofftechnik

1998-04-01T23:59:59.000Z

168

ORIGINAL ARTICLE Strength and microstructure of laser fusion-welded TiSS  

E-Print Network [OSTI]

ORIGINAL ARTICLE Strength and microstructure of laser fusion-welded Ti­SS dissimilar material pair robust and reliable dissimilar metal joints has the potential to enable new func- tionalities and reduce the manufacturing costs of medical devices. The need for dissimilar material welds in the med- ical device industry

Yao, Y. Lawrence

169

Mechanical and metallurgical properties of MMC friction welds  

SciTech Connect (OSTI)

The mechanical and metallurgical properties of similar and dissimilar welds involving aluminum-based metal matrix composite (MMC) base material were investigated using factorial experimentation. The test materials comprised aluminum-based alloy 6061/Al{sub 2}O{sub 3} (W6A.10A-T6), aluminum Alloy 6061-T6 and AISI 304 stainless steel. Notch tensile strength increased when high friction pressures were employed during MMC/MMC, MMC/Alloy 6061, MMC/AISI 304 stainless steel and Alloy 6061/Alloy 6061 friction welding. In MMC/Alloy 6061 welds, notch tensile strength also increased when high forging pressures were employed. Applied oxide films on both the MMC and AISI stainless steel substrates had a markedly detrimental effect on dissimilar weld mechanical properties. The optimum notch tensile strength properties were produced when high friction pressure values were applied during dissimilar MMC/AISI 304 stainless steel welding. High friction pressure had two beneficial effects, i.e., it decreased the thickness of the FeAl{sub 3} intermetallic film and it promoted disruption and dispersal of oxide films at the joint interface. In direct contrast, the presence of thick anodized oxide films on the MMC substrate surface prior to friction welding had no observable influence on MMC/MMC weld mechanical properties.

Li, Z.; Maldonado, C.; North, T.H. [Univ. of Toronto, Ontario (Canada). Dept. of Metallurgy and Materials Science; Altshuller, B. [Alcan R and D Labs., Kingston, Ontario (Canada)

1997-09-01T23:59:59.000Z

170

Dissimilar-weld failure analysis and development program. Volume 1. Executive summary. Final report  

SciTech Connect (OSTI)

Failure of dissimilar metal welds is a major cause of forced outage in fossil boilers. A research project was carried out to: Develop a clearer understanding of the underlying causes of dissimilar weld failures; develop a methodology for estimating the residual life of service welds; develop a critical discriminatory test to predict the relative performance of welds; and develop guidelines for improved-performance dissimilar welds. The research methodology included review of prior experience as well as evaluation of a large number of failed and unfailed welds obtained from boiler superheaters or reheaters. The evaluations included metallography, mechanical testing and boiler inspections; in many cases, tube loading histories at the dissimilar weld locations were estimated. This work resulted in a clearer understanding of the root cause of weld failures. Furthermore, a quantitative relationship was derived between failure susceptibility and weld metal ''system'' loads, cycles, and temperatures (all critical parameters in weld performance). Accelerated discriminatory tests, including a number of geometries and modes of stressing and thermal cycling, were examined. The shortest time to failure, good reproducibility, and the capability to control loads and monitor cracking were achieved in a test which involved applying four-point bending loads to internally pressurized full-size tubular specimens. Tests at 593/sup 0/C (1100/sup 0/F), which involved temperature cycling, had failure times of only 400 h for stainless-steel fillers and 1500 h for nickel-base fillers. Guidelines for improved welds were derived from all the program results. They include and offer guidance on the considerations of weld-filler selection, weld geometry, heat treatment, etc., in relation to expected service conditions and on locating DMWs to optimize service performance. 7 refs., 18 figs., 3 tabs.

Not Available

1985-11-01T23:59:59.000Z

171

Modeling of thermal plasma arc technology FY 1994 report  

SciTech Connect (OSTI)

The thermal plasma arc process is under consideration to thermally treat hazardous and radioactive waste. A computer model for the thermal plasma arc technology was designed as a tool to aid in the development and use of the plasma arc-Joule beating process. The value of this computer model is to: (a) aid in understanding the plasma arc-Joule beating process as applied to buried waste or exhumed buried waste, (b) help design melter geometry and electrode configuration, (c) calculate the process capability of vitrifying waste (i.e., tons/hour), (d) develop efficient plasma and melter operating conditions to optimize the process and/or reduce safety hazards, (e) calculate chemical reactions during treatment of waste to track chemical composition of off-gas products, and composition of final vitrified waste form and (f) help compare the designs of different plasma-arc facilities. A steady-state model of a two-dimensional axisymmetric transferred plasma arc has been developed and validated. A parametric analysis was performed that studied the effects of arc length, plasma gas composition, and input power on the temperatures and velocity profiles of the slag and plasma gas. A two-dimensional transient thermo-fluid model of the US Bureau of Mines plasma arc melter has been developed. This model includes the growth of a slag pool. The thermo-fluid model is used to predict the temperature and pressure fields within a plasma arc furnace. An analysis was performed to determine the effects of a molten metal pool on the temperature, velocity, and voltage fields within the slag. A robust and accurate model for the chemical equilibrium calculations has been selected to determine chemical composition of final waste form and off-gas based on the temperatures and pressures within the plasma-arc furnace. A chemical database has been selected. The database is based on the materials to be processed in the plasma arc furnaces.

Hawkes, G.L.; Nguyen, H.D.; Paik, S.; McKellar, M.G.

1995-03-01T23:59:59.000Z

172

Concurrent ultrasonic weld evaluation system  

DOE Patents [OSTI]

A system for concurrent, non-destructive evaluation of partially completed welds for use in conjunction with an automated welder is disclosed. The system utilizes real time, automated ultrasonic inspection of a welding operation as the welds are being made by providing a transducer which follows a short distance behind the welding head. Reflected ultrasonic signals are analyzed utilizing computer based digital pattern recognition techniques to discriminate between good and flawed welds on a pass by pass basis. The system also distinguishes between types of weld flaws. 5 figs.

Hood, D.W.; Johnson, J.A.; Smartt, H.B.

1987-12-15T23:59:59.000Z

173

Vacuum arc deposition devices  

SciTech Connect (OSTI)

The vacuum arc is a high-current, low-voltage electrical discharge which produces a plasma consisting of vaporized and ionized electrode material. In the most common cathodic arc deposition systems, the arc concentrates at minute cathode spots on the cathode surface and the plasma is emitted as a hypersonic jet, with some degree of contamination by molten droplets [known as macroparticles (MPs)] of the cathode material. In vacuum arc deposition systems, the location and motion of the cathode spots are confined to desired surfaces by an applied magnetic field and shields around undesired surfaces. Substrates are mounted on a holder so that they intercept some portion of the plasma jet. The substrate often provides for negative bias to control the energy of depositing ions and heating or cooling to control the substrate temperature. In some systems, a magnetic field is used to guide the plasma around an obstacle which blocks the MPs. These elements are integrated with a deposition chamber, cooling, vacuum gauges and pumps, and power supplies to produce a vacuum arc deposition system.

Boxman, R.L.; Zhitomirsky, V.N. [Electrical Discharge and Plasma Laboratory, Faculty of Engineering, Tel Aviv University, P.O. Box 39040, Tel Aviv 69978 (Israel)

2006-02-15T23:59:59.000Z

174

Effect of strength mismatch on fracture toughness of HSLA steel weld joints  

SciTech Connect (OSTI)

The purpose of this experimental work is to present the results of measured toughness and strength on mismatched weld joints made on HSLA steel grade HT 80. In the determined over and undermatched weld joints the local mismatching in the through thickness direction was found by hardness measurement. It seems that local mismatch because of WM low toughness has controlled the fracture behavior of weld metal and HAZ in both cases instead of the global one. Direct local CTOD({delta}{sub 5}) technique is found to be particular useful for the determination of fracture toughness values on mismatched weld joints.

Rak, I.; Gliha, V.; Gubeljak, N.; Praunseis, Z. [Univ. of Maribor (Slovenia). Faculty of Mechanical Engineering; Kocak, M. [GKSS Research Center, Geesthacht (Germany). Inst. of Material Research

1995-12-31T23:59:59.000Z

175

Certification of a weld produced by friction stir welding  

DOE Patents [OSTI]

Methods, devices, and systems for providing certification of friction stir welds are disclosed. A sensor is used to collect information related to a friction stir weld. Data from the sensor is compared to threshold values provided by an extrinsic standard setting organizations using a certification engine. The certification engine subsequently produces a report on the certification status of the weld.

Obaditch, Chris; Grant, Glenn J

2013-10-01T23:59:59.000Z

176

Microstructural characterization of dissimilar welds between alloy 800 and HP heat-resistant steel  

SciTech Connect (OSTI)

In this study, dissimilar welds between HP heat-resistant steel and Incoloy 800 were made with four different filler materials including: 309 stainless steel and nickel-based Inconel 82, 182 and 617. The microstructure of the base metals, weld metals and their interfaces were characterized by utilizing optical and scanning electron microscopy. Grain boundaries migration in the weld metals was studied. It was found that the migration of grain boundaries in the Inconel 82 weld metal was very extensive. Precipitates of TiC and M{sub 23}C{sub 6} (M = Cr and Mo) in the Inconel 617 weld metal are identified. The necessary conditions for the formation of cracks close to the fusion line of the 309-HP joints are described. Furthermore unmixed zone near the fusion line between HP steel base metal and Inconel 82 weld metal is discussed. An epitaxial growth is characterized at the fusion line of the 309-Alloy 800 and Inconel 617-Alloy 800 joints.

Dehmolaei, R. [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of); Shamanian, M. [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of)], E-mail: shamanian@cc.iut.ac.ir; Kermanpur, A. [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of)

2008-10-15T23:59:59.000Z

177

College of Design ARC Architecture  

E-Print Network [OSTI]

College of Design ARC Architecture KEY: # = new course * = course changed = course dropped,landscape,andarchitecturalspaceswithattentiontotheirapplicationtothearchitecturalexperience.Studio:4hoursperweek. Prereq: Admission to the School of Architecture. ARC 102 DRAWING II: OBSERVATIONAL OF ARCHITECTURE. (3

MacAdam, Keith

178

Wear resistance of laser cladding and plasma spray welding layer on stainless steel surface  

Science Journals Connector (OSTI)

The effect of coatings, which are formed with laser cladding and plasma spray welding on 1Cr18Ni9Ti base metal, on wear resistance is studied, A 5-kW transverse flowing CO2 laser...

Wang, Xinlin; Shi, Shihong; Zheng, Qiguang

2004-01-01T23:59:59.000Z

179

MECHANICAL PROPERTIES AND MICROSTRUCTURAL CHARACTERIZATION OF A MULTILAYERED MULTIPASS FRICTION STIR WELD IN STEEL  

SciTech Connect (OSTI)

Multilayered multipass friction stir welding (MM-FSW) makes it possible to use FSW to fabricate thick-section structures. In this work, MM-FSW was demonstrated on a high strength low alloy steel; ASTM A572 Grade 50. Three steel plates with thicknesses of 0.18", 0.18", 0.24" respectively were stacked and friction stir welded together to form a 0.6" thick welded structure. The welded plate was sectioned into rectangular bars transverse to the weld direction for tensile testing to evaluate mechanical properties. Digital image correlation (DIC) was employed to map the local strain fields during tensile testing. The initial failure was found to occur simultaneously at the bottom and middle layers away from the weld zone. The top layer failed last in the base metal. The failure locations were consistent among different samples tested. Also, Charpy V-notch impact tests were conducted for weld metal, heat affected zone, and the base metal at each layer as a function of temperature. The weld microstructures were characterized using optical and electron microscopy and micro-hardness mapping.

Lim, Yong Chae [ORNL; Sanderson, Samuel [MegaStir Technologies LLC; Mahoney, Murray [Consultant; Qiao, Dongxiao [ORNL; Wang, Yanli [ORNL; Zhang, Wei [ORNL; Feng, Zhili [ORNL

2013-01-01T23:59:59.000Z

180

Robotic Welding and Inspection System  

SciTech Connect (OSTI)

This paper presents a robotic system for GTA welding of lids on cylindrical vessels. The system consists of an articulated robot arm, a rotating positioner, end effectors for welding, grinding, ultrasonic and eddy current inspection. Features include weld viewing cameras, modular software, and text-based procedural files for process and motion trajectories.

H. B. Smartt; D. P. Pace; E. D. Larsen; T. R. McJunkin; C. I. Nichol; D. E. Clark; K. L. Skinner; M. L. Clark; T. G. Kaser; C. R. Tolle

2008-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Friction stir welding tool and process for welding dissimilar materials  

DOE Patents [OSTI]

A friction stir welding tool and process for lap welding dissimilar materials are detailed. The invention includes a cutter scribe that penetrates and extrudes a first material of a lap weld stack to a preselected depth and further cuts a second material to provide a beneficial geometry defined by a plurality of mechanically interlocking features. The tool backfills the interlocking features generating a lap weld across the length of the interface between the dissimilar materials that enhances the shear strength of the lap weld.

Hovanski, Yuri; Grant, Glenn J; Jana, Saumyadeep; Mattlin, Karl F

2013-05-07T23:59:59.000Z

182

Dissimilar-weld failure analysis and development program  

SciTech Connect (OSTI)

As a result of the work performed under RP 1874-1, the factors influencing the performance of dissimilar metal welds (DMWs) in elevated temperature power plant boiler service have been defined. Details of the results are given in other volumes of this report series. In this volume, design and procedure guidelines for improving DMW performance are provided. DMW life can be extended by: locating DMWs such that service conditions are conducive to long life; such locations may be identified by the use of the computerized analytical program PODIS, developed under RP 1874; using preferred weld filler metals; and using specific weld configurations. Details of each of these approaches are described herein. 5 figs., 2 tabs.

Roberts, D.I.; Ryder, R.H.; Grunloh, H.J.; Thurgood, B.E. (General Atomics, San Diego, CA (USA))

1989-11-01T23:59:59.000Z

183

Analysis of dissimilar welds exposed to high temperature H{sub 2}/H{sub 2}S conditions in a hydrodesulfurizing (HDS) unit  

SciTech Connect (OSTI)

In high temperature applications, dissimilar welds made with nickel-base alloy filler metals provide extended service lives as compared to similar welds made with stainless steel filler metals. Although considerable refinery experience exists, it is difficult to find published information for pressure boundary welds made with nickel-base filler metal in hot hydrogen and/or H{sub 2}S services. The Amuay Refinery has used nickel base alloy filler metals to join clad piping components in a number of piping applications. This paper details the results of an analysis of clad 1{1/4}Cr-{1/2} Mo steel hydroprocessing reactor effluent piping samples removed from service to assess the long term effects of hydrogen and H{sub 2}S on the dissimilar weld. Results of mechanical testing and metallurgical analysis reveal that no significant loss in properties occurred. Details of the weld procedures and weld joint design are provided.

Penuela, L.E.; Chirinos, J.G. [PDVSA Manufacture y Mercado, Judibana (Venezuela). Centro Refinacion Paraguana; Dobis, J.D. [KLAD Inc., Elkton, MD (United States)

1999-11-01T23:59:59.000Z

184

Hall-effect arc protector  

DOE Patents [OSTI]

The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.

Rankin, Richard A. (Ammon, ID); Kotter, Dale K. (Shelley, ID)

1997-01-01T23:59:59.000Z

185

Hall-effect arc protector  

DOE Patents [OSTI]

The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.

Rankin, R.A.; Kotter, D.K.

1997-05-13T23:59:59.000Z

186

Experimental validation of finite element codes for welding deformations  

E-Print Network [OSTI]

Institute for Energy Technology, N-2027 Kjeller, Norway. Abstract A single pass Metal Inert Gas welding. Hamidec , H. G. Fjærd , A. Moa , M. Belletc a SINTEF Materials Technology, N-0314 Oslo, Norway. b University of Oslo, N-0316 Oslo, Norway. c CEMEF Ecole des Mines de Paris, Sophia Antipolis, France. d

Boyer, Edmond

187

Microstructural issues in a friction-stir-welded aluminum alloy  

SciTech Connect (OSTI)

Recent observations of microstructures associated with friction-stir welding (FSW) in a number of aluminum alloys have consistently demonstrated the actual weld zone to consist of a (dynamically) recrystallized grain structure resulting from the extreme, solid-state, plastic deformation characterizing the process. Because of solubilities associated with the various precipitates in 7075 and 6061 aluminum alloys, and the fact that the precipitates were either homogeneously distributed throughout both the original (unwelded) work-piece plates and the well zones (or formed varying densities of Widmanstaetten patterns within the original and recrystallized grains), it has been difficult to follow the stirring of stable, second-phase particles from the base metal (work-piece) into the weld zone. In the present investigation, a compositionally modified 1100 aluminum alloy (nominally 99.2% Al, 0.5% Fe, 0.15% Cu, 0.12% Si, 0.05 Mn, 0.04 Ti, balance in weight percent of Be and Mg), forming a stable microdendritic (second-phase), equiaxed, cell structure was friction-stir welded. These thermally stable, geometrically specific, precipitates in the base metal were compared with their disposition within the friction-stir-weld zone. In addition, as-cast plates of this alloy were cold-rolled 50% and friction-stir-welded in order to compare these two schedules (as-cast and 50% cold-rolled) in terms of residual hardness variations and related microstructural issues as well as the effect of prior deformation on the friction-stir welding process.

Flores, O.V.; Kennedy, C.; Murr, L.E.; Brown, D.; Pappu, S.; Nowak, B.M.; McClure, J.C. [Univ. of Texas, El Paso, TX (United States)] [Univ. of Texas, El Paso, TX (United States)

1998-02-03T23:59:59.000Z

188

MAIN APPLICATIONS Spot welding  

E-Print Network [OSTI]

IRB 6400 MAIN APPLICATIONS Spot welding Press tending Material handling Machine tending Palletizing with high material strength. The arms are mechanically balanced and equipped with double bearings. Advanced DATA, IRB 6400 INDUSTRIAL ROBOT WORKING RANGE AND LOAD DIAGRAM IRB 6400PE IRB 6400R IRB 6400S PR10036EN

De Luca, Alessandro

189

GIS Fundamentals: Supplementary Lessons with ArcGIS Introduction to ArcGIS Lesson 1: Introduction to ArcGIS  

E-Print Network [OSTI]

GIS Fundamentals: Supplementary Lessons with ArcGIS Introduction to ArcGIS 1 Lesson 1: Introduction to ArcGIS What You'll Learn: -Start ArcMap -Create a new map -Add data layers -Pan and zoom -Change data errors. Background: This is the first in a series of introductory exercises for ArcGIS

Harbor, David

190

The stability and the conditions for initiation of electric-arc discharges in railguns  

Science Journals Connector (OSTI)

Characteristic physical features of plasma formations in high-velocity sliding electric contacts are treated, in particular, those in railguns with both electric-arc and metal armatures. Comparison is made of ...

A. P. Glinov

2007-04-01T23:59:59.000Z

191

Controlling electrode gap during vacuum arc remelting at low melting current  

DOE Patents [OSTI]

An apparatus and method are disclosed for controlling electrode gap in a vacuum arc remelting furnace, particularly at low melting currents. Spectrographic analysis is performed of the metal vapor plasma, from which estimates of electrode gap are derived. 5 figs.

Williamson, R.L.; Zanner, F.J.; Grose, S.M.

1997-04-15T23:59:59.000Z

192

Characterization of Service Induced Flaws on the Far Side of Austenitic Welds Using Phased Array Technology  

SciTech Connect (OSTI)

Conventional ultrasonic testing methods continue to exhibit problems for applications involving coarse-grained structures. Pacific Northwest National Laboratory is evaluating the capabilities and limitations of phased array (PA) technology to detect service-type flaws in these coarse-grained materials. The work is being sponsored by the U.S. Nuclear Regulatory Commission, Office of Research. Work to determine detection capabilities through welds with varied grain structures is being explored to provide a better understanding of the acoustic properties of these welded structures. Piping specimens with welds fabricated in vertical and horizontal positions to simulate field conditions have been studied. The insights gained from the austenitic piping will be applied to dissimilar metal weld configurations, corrosion resistant clad piping and cast stainless steels. This paper presents results for using PA ultrasonic technology to determine the effectiveness of detecting and accurately characterizing flaws on the far-side of austenitic piping welds.

Anderson, Michael T.; Cumblidge, Stephen E.

2004-01-01T23:59:59.000Z

193

Graphite electrode DC arc furnace. Innovative technology summary report  

SciTech Connect (OSTI)

The Graphite Electrode DC Arc Furnace (DC Arc) is a high-temperature thermal process, which has been adapted from a commercial technology, for the treatment of mixed waste. A DC Arc Furnace heats waste to a temperature such that the waste is converted into a molten form that cools into a stable glassy and/or crystalline waste form. Hazardous organics are destroyed through combustion or pyrolysis during the process and the majority of the hazardous metals and radioactive components are incorporated in the molten phase. The DC Arc Furnace chamber temperature is approximately 593--704 C and melt temperatures are as high as 1,500 C. The DC Arc system has an air pollution control system (APCS) to remove particulate and volatiles from the offgas. The advantage of the DC Arc is that it is a single, high-temperature thermal process that minimizes the need for multiple treatment systems and for extensive sorting/segregating of large volumes of waste. The DC Arc has the potential to treat a wide range of wastes, minimize the need for sorting, reduce the final waste volumes, produce a leach resistant waste form, and destroy organic contaminants. Although the DC arc plasma furnace exhibits great promise for treating the types of mixed waste that are commonly present at many DOE sites, several data and technology deficiencies were identified by the Mixed Waste Focus Area (MWFA) regarding this thermal waste processing technique. The technology deficiencies that have been addressed by the current studies include: establishing the partitioning behavior of radionuclides, surrogates, and hazardous metals among the product streams (metal, slag, and offgas) as a function of operating parameters, including melt temperature, plenum atmosphere, organic loading, chloride concentration, and particle size; demonstrating the efficacy of waste product removal systems for slag and metal phases; determining component durability through test runs of extended duration, evaluating the effect of feed composition variations on process operating conditions and slag product performance; and collecting mass balance and operating data to support equipment and instrument design.

NONE

1999-05-01T23:59:59.000Z

194

Resistance Spot Welding of Galvanized Steel: Part II. Mechanisms of Spot Weld Nugget Formation  

E-Print Network [OSTI]

of material variations and weld process parameter modifications on resistance spot welding of coated( l Resistance Spot Welding of Galvanized Steel: Part II. Mechanisms of Spot Weld Nugget Formation S. A. GEDEON and T. W. EAGAR Dynamic inspection monitoring of the weld current, voltage, resistance

Eagar, Thomas W.

195

Laser Welding of Aluminum and Aluminum Alloys  

E-Print Network [OSTI]

.. ) Laser Welding of Aluminum and Aluminum Alloys Welds made with sharp bevel-groove weld aluminum and by aluminum alloy 5456 have been studied. The results indicate that initial absorption varies of the most dramatic illustrations of the differences in beam characteristics occurs when welding aluminum

Eagar, Thomas W.

196

Arc fault detection system  

DOE Patents [OSTI]

An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.

Jha, Kamal N. (Bethel Park, PA)

1999-01-01T23:59:59.000Z

197

Application of Centrifugation to the Large-Scale Purification of Electric Arc-Produced Single-Walled Carbon Nanotubes  

Science Journals Connector (OSTI)

Application of Centrifugation to the Large-Scale Purification of Electric Arc-Produced Single-Walled Carbon Nanotubes ... Electric arc-discharge AP-SWNTs were obtained from Carbon Solutions, Inc. (www.carbonsolution.com). ... Using microwave processing and 4 M HCl acid reflux for 6 h we were able to remove residual metal (Ni, Y) in arc-discharge SWNTs to a level lower than 0.2 wt % (?0.04 at. ...

Aiping Yu; Elena Bekyarova; Mikhail E. Itkis; Danylo Fakhrutdinov; Robert Webster; Robert C. Haddon

2006-07-08T23:59:59.000Z

198

On-Line Weld NDE with IR Thermography  

Broader source: Energy.gov (indexed) [DOE]

Weld cracks - Weld porosity Most critical Excessive indentation Stuck weld (insufficient fusion) Less critical Cracks Porosity 10 Managed by UT-Battelle for the Department of...

199

Assisting manual welding with robot  

Science Journals Connector (OSTI)

This paper presents a first attempt to assist manual welding with a physically interactive robot. An interactive control scheme is developed to suppress the vibrations of torch during the welding of novice welders. The torch is attached to the end-effector of a haptic-robot. Human and robot act together on the welding torch: the human controls the direction and speed; the robot suppresses the sudden and abrupt motions. The control scheme is developed by experimenting with an air-paint-brush. The painting process emulates the actual welding. Such an emulating environment is useful to surmount the difficulties of experimentation with actual welding. The impedance parameters of the control scheme are investigated. A damping value is determined for an effective vibration suppression and minimum human effort. A variable impedance control scheme is applied to ease the manipulation of the torch while not welding. The results of real welding of novice welders with and without robot assistance are presented. There is a considerable improvement in the performance of the welders when they are assisted with the robot.

Mustafa Suphi Erden; Bobby Mari?

2011-01-01T23:59:59.000Z

200

Instability of a Vacuum Arc Centrifuge M. J. Hole, R. S. Dallaqua, S. W. Simpson* and E. Del Bosco.  

E-Print Network [OSTI]

vapour ablated from the cathode of the discharge by the action of vacuum arcs (see Figure 1) with a metalInstability of a Vacuum Arc Centrifuge M. J. Hole, R. S. Dallaqua, S. W. Simpson* and E. Del Bosco of Electrical and Information Engineering, University of Sydney, N.S.W. 2006 Australia Laboratório Associado de

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Pulse shaping effects on weld porosity in laser beam spot welds : contrast of long- & short- pulse welds.  

SciTech Connect (OSTI)

Weld porosity is being investigated for long-pulse spot welds produced by high power continuous output lasers. Short-pulse spot welds (made with a pulsed laser system) are also being studied but to a much small extent. Given that weld area of a spot weld is commensurate with weld strength, the loss of weld area due to an undefined or unexpected pore results in undefined or unexpected loss in strength. For this reason, a better understanding of spot weld porosity is sought. Long-pulse spot welds are defined and limited by the slow shutter speed of most high output power continuous lasers. Continuous lasers typically ramp up to a simmer power before reaching the high power needed to produce the desired weld. A post-pulse ramp down time is usually present as well. The result is a pulse length tenths of a second long as oppose to the typical millisecond regime of the short-pulse pulsed laser. This study will employ a Lumonics JK802 Nd:YAG laser with Super Modulation pulse shaping capability and a Lasag SLS C16 40 W pulsed Nd:YAG laser. Pulse shaping will include square wave modulation of various peak powers for long-pulse welds and square (or top hat) and constant ramp down pulses for short-pulse welds. Characterization of weld porosity will be performed for both pulse welding methods.

Ellison, Chad M. (Honeywell FM& T, Kansas City, MO); Perricone, Matthew J. (R.J. Lee Group, Inc., Monroeville, PA); Faraone, Kevin M. (BWX Technologies, Inc., Lynchburg, VA); Norris, Jerome T.

2007-10-01T23:59:59.000Z

202

Atom probe field-ion microscopy investigation of nickel base superalloy welds  

SciTech Connect (OSTI)

Microstructure development and elemental partitioning between {gamma} and {gamma}{prime} were measured in PWA-1480 electron beam welds and CMSX-4 pulsed-laser welds. In PWA-1480 EB welds, eutectic {gamma}{prime} phases were observed along the dendritic boundaries. The elemental partitioning between {gamma} and {gamma}{prime} was found to be similar to that in PWA-1480 base metal. In CMSX-4 pulsed laser welds, negligible eutectic {gamma}{prime} was observed. In addition, fine and irregularly shaped {gamma}{prime} precipitates were observed. The elemental partitioning between {gamma} and {gamma}{prime} was found to be different from that measured in the base metal. Large concentration gradients were observed in the {gamma} phase. The {gamma}{prime} precipitation kinetics in CM247DS alloy was measured using dilatometry and showed differences with different cooling rates. The microstructural investigations showed that at large undercoolings the number density of {gamma}{prime} precipitates increased and led to a finer size. This supports the microstructure development observations in PWA-1480 and CMSX-4 welds. Thermodynamic and kinetic calculations for the Ni-Al-Cr alloy system showed that as the cooling rate increases, the {gamma}{prime} growth leads to large concentration gradients in the {gamma} phase. The calculations agree with the atom probe results from PWA-1480 and CMSX-4 welds.

Babu, S.S.; David, S.A.; Vitek, J.M.; Miller, M.K.

1998-11-01T23:59:59.000Z

203

Inspection of Nickel Alloy Welds: Results from Five Year International Program  

SciTech Connect (OSTI)

The U.S. Nuclear Regulatory Commission established and coordinated the international Program for the Inspection of Nickel alloy Components (PINC). The goal of PINC was to evaluate the capabilities of various nondestructive examination (NDE) techniques to detect and characterize primary water stress corrosion cracking (PWSCC) in dissimilar metal welds. Round-robin results showed that a combination of conventional and phased-array ultrasound provide the highest performance for flaw detection and depth sizing in dissimilar metal piping welds. The effective detection of flaws in bottom-mounted instrumentation penetrations by eddy current and ultrasound shows that it may be possible to reliably inspect these components in the field.

Prokofiev, Iouri; Cumblidge, Stephen E.; Doctor, Steven R.

2011-06-23T23:59:59.000Z

204

Microstructural characterization in dissimilar friction stir welding between 304 stainless steel and st37 steel  

SciTech Connect (OSTI)

In the present study, 3 mm-thick plates of 304 stainless steel and st37 steel were welded together by friction stir welding at a welding speed of 50 mm/min and tool rotational speed of 400 and 800 rpm. X-ray diffraction test was carried out to study the phases which might be formed in the welds. Metallographic examinations, and tensile and microhardness tests were used to analyze the microstructure and mechanical properties of the joint. Four different zones were found in the weld area except the base metals. In the stir zone of the 304 stainless steel, a refined grain structure with some features of dynamic recrystallization was evidenced. A thermomechanically-affected zone was characterized on the 304 steel side with features of dynamic recovery. In the other side of the stir zone, the hot deformation of the st37 steel in the austenite region produced small austenite grains and these grains transformed to fine ferrite and pearlite and some products of displacive transformations such as Widmanstatten ferrite and martensite by cooling the material after friction stir welding. The heat-affected zone in the st37 steel side showed partially and fully refined microstructures like fusion welding processes. The recrystallization in the 304 steel and the transformations in the st37 steel enhanced the hardness of the weld area and therefore, improved the tensile properties of the joint. - Highlights: Black-Right-Pointing-Pointer FSW produced sound welds between st37 low carbon steel and 304 stainless steel. Black-Right-Pointing-Pointer The SZ of the st37 steel contained some products of allotropic transformation. Black-Right-Pointing-Pointer The material in the SZ of the 304 steel showed features of dynamic recrystallization. Black-Right-Pointing-Pointer The finer microstructure in the SZ increased the hardness and tensile strength.

Jafarzadegan, M. [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of) [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Feng, A.H. [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China)] [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Abdollah-zadeh, A., E-mail: zadeh@modares.ac.ir [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); Saeid, T. [Advanced Materials Research Center, Sahand University of Technology, P.O. Box: 51335-1996, Tabriz (Iran, Islamic Republic of)] [Advanced Materials Research Center, Sahand University of Technology, P.O. Box: 51335-1996, Tabriz (Iran, Islamic Republic of); Shen, J. [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China)] [State Key Laboratory of Advanced Welding Production Technology, School of Materials Science and Eng., Harbin Institute of Technology, P.O. Box: 150001, Harbin (China); Assadi, H. [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of)] [Department of Materials Eng., Tarbiat Modares University, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of)

2012-12-15T23:59:59.000Z

205

Automatic monitoring of vibration welding equipment  

DOE Patents [OSTI]

A vibration welding system includes vibration welding equipment having a welding horn and anvil, a host device, a check station, and a robot. The robot moves the horn and anvil via an arm to the check station. Sensors, e.g., temperature sensors, are positioned with respect to the welding equipment. Additional sensors are positioned with respect to the check station, including a pressure-sensitive array. The host device, which monitors a condition of the welding equipment, measures signals via the sensors positioned with respect to the welding equipment when the horn is actively forming a weld. The robot moves the horn and anvil to the check station, activates the check station sensors at the check station, and determines a condition of the welding equipment by processing the received signals. Acoustic, force, temperature, displacement, amplitude, and/or attitude/gyroscopic sensors may be used.

Spicer, John Patrick; Chakraborty, Debejyo; Wincek, Michael Anthony; Wang, Hui; Abell, Jeffrey A; Bracey, Jennifer; Cai, Wayne W

2014-10-14T23:59:59.000Z

206

Soft zone formation in dissimilar welds between two Cr-Mo steels  

SciTech Connect (OSTI)

Two dissimilar weldments between 9Cr-1Mo and 2.25Cr-1Mo ferritic steels have been characterized for their microstructural stability during various postweld heat treatments (PWHTs). The samples for the investigation were extracted from bead-on-plate weldments made by depositing 2.25Cr-1Mo weld metal on 9Cr-1Mo base plate and vice versa. Subsequent application of PWHT resulted in the formation of a soft zone in the low Cr ferritic steel weld or base plate. A carbide-rich hard zone, adjoining the soft zone, was also detected in the high Cr side of the weldment. Unmixed zones in the weld metal provided additional soft and hard zones in the weld metals. The migration of carbon from low-Cr steel to high-Cr steel, driven by the carbon activity gradient, has been shown to be responsible for the formation of soft and hard zones. A carbon activity diagram for 2.25Cr-1Mo/9Cr-1Mo weldments has been proposed to aid in the selection of welding consumables for reducing or preventing the soft zone formation.

Albert, S.K.; Gill, T.P.S.; Tyagi, A.K.; Mannan, S.L.; Rodriguez, P. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Kulkarni, S.D. [Indian Inst. of Tech., Bombay (India)

1997-03-01T23:59:59.000Z

207

Characterizations of 21-4N to 4Cr9Si2 stainless steel dissimilar joint bonded by electric-resistance-heat-aided friction welding  

Science Journals Connector (OSTI)

A new welding process, electric-resistance-heat-aided friction welding (ERHAFW), was introduced in this study. To further improve the joint quality and energy-saving, electric resistance welding was combined with the conventional continuous-drive friction welding. 21-4N (austenitic stainless steel) and 4Cr9Si2 (martensitic stainless steel) valve steel rods of 4 mm diameter were used as base metals. The results show that electric-resistance-heat-aided friction welding can be applied to join thin rods within a relatively short time, which is very difficult for conventional friction welding (FW). The microstructure of ERHAFW bonded 21-4N to 4Cr9Si2 presents non-uniform across the joint. Different structure zones are observed from the weld line to both sides, which are the weld center, thermo-mechanically affected zone (TMAZ) and heat affected zone (HAZ). These regions exhibit different structures owing to the difference in the thermophysical and mechanical properties of these two steels under the fast heating and cooling during welding. The variation of microhardness in the joint is attributed to the microstructure change. The higher microhardness is obtained in the weld center and TMAZ of 4Cr9Si2 corresponding to the presence of fine tempered martensite and carbides.

Wen-Ya Li; Min Yu; Jinglong Li; Guifeng Zhang; Shiyuan Wang

2009-01-01T23:59:59.000Z

208

Confined plasma gliding arc discharges  

Science Journals Connector (OSTI)

A confined plasma gliding arc is produced in a reactor with two-electrodes contained within a very narrow channel and water spray injected into the discharge. The evolution of pH and conductivity and the formation of hydrogen peroxide in pure water with different carrier gases and the decolourisation and mineralisation of an organic dye were compared with results for a non-confined three-electrode gliding arc reactor. The energy efficiency for the decolourisation of an organic blue dye in the confined reactor is twice that of the non-confined reactor. Significant levels of total organic carbon are removed in the confined plasma reactor.

Radu Burlica; Bruce R. Locke

2008-01-01T23:59:59.000Z

209

Contamination and solid state welds.  

SciTech Connect (OSTI)

Since sensitivity to contamination is one of the verities of solid state joining, there is a need for assessing contamination of the part(s) to be joined, preferably nondestructively while it can be remedied. As the surfaces that are joined in pinch welds are inaccessible and thus provide a greater challenge, most of the discussion is of the search for the origin and effect of contamination on pinch welding and ways to detect and mitigate it. An example of contamination and the investigation and remediation of such a system is presented. Suggestions are made for techniques for nondestructive evaluation of contamination of surfaces for other solid state welds as well as for pinch welds. Surfaces that have good visual access are amenable to inspection by diffuse reflection infrared Fourier transform (DRIFT) spectroscopy. Although other techniques are useful for specific classes of contaminants (such as hydrocarbons), DRIFT can be used most classes of contaminants. Surfaces such as the interior of open tubes or stems that are to be pinch welded can be inspected using infrared reflection spectroscopy. It must be demonstrated whether or not this tool can detect graphite based contamination, which has been seen in stems. For tubes with one closed end, the technique that should be investigated is emission infrared spectroscopy.

Mills, Bernice E.

2007-05-01T23:59:59.000Z

210

MagLab - Arc Lamp Tutorial  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

with 2,000 cells to create an arc across a 4-inch (100 millimeter) gap. When suitable electric generators became available in the late 1870s, the practical use of arc lamps began....

211

The fractal nature of vacuum arc cathode spots  

SciTech Connect (OSTI)

Cathode spot phenomena show many features of fractals, for example self-similar patterns in the emitted light and arc erosion traces. Although there have been hints on the fractal nature of cathode spots in the literature, the fractal approach to spot interpretation is underutilized. In this work, a brief review of spot properties is given, touching the differences between spot type 1 (on cathodes surfaces with dielectric layers) and spot type 2 (on metallic, clean surfaces) as well as the known spot fragment or cell structure. The basic properties of self-similarity, power laws, random colored noise, and fractals are introduced. Several points of evidence for the fractal nature of spots are provided. Specifically power laws are identified as signature of fractal properties, such as spectral power of noisy arc parameters (ion current, arc voltage, etc) obtained by fast Fourier transform. It is shown that fractal properties can be observed down to the cutoff by measurement resolution or occurrence of elementary steps in physical processes. Random walk models of cathode spot motion are well established: they go asymptotically to Brownian motion for infinitesimal step width. The power spectrum of the arc voltage noise falls as 1/f {sup 2}, where f is frequency, supporting a fractal spot model associated with Brownian motion.

Anders, Andre

2005-05-27T23:59:59.000Z

212

Vacuum arc ignition by penning discharge in a strong magnetic field  

SciTech Connect (OSTI)

Vacuum arc with cathode spots on the cold electrode is widely used as a plasma generator in a such kind of devices like metal ion sources, plasma cathode electron guns, thing films deposition facilities and others. Most vacuum arc devices utilize a high voltage discharge across an insulator surface to provide a trigger plasma which in turn initiates the main arc discharge. Operation of vacuum arc in a repetitively pulsed mode required a stable triggering system for the long time. But with a discharge across the insulators the number of stable pulses is limited by 100,000 or little bit more. The better method for vacuum arc ignition is low pressure discharge. As shown in this paper it is possible to increase the lifetime of the ignition system in 10 times at least, but negative characteristic of this system is a relatively high pressure (about 0.1 mtorr). In some kinds of vacuum arc applications it is impermissible because it leads to the {open_quotes}contamination{close_quotes} of the metal plasma by the gaseous one. In order to decrease the background pressure, using the gas discharge ignition system for vacuum arc, Penning discharge is suggested. The main new feature of this system is an applying the strong magnetic field not only for stabilization of the cathode spot moving and for the rise the high charge states of ions in metal plasma, but also for the essential decrease the lowest point of the background gas pressure when the Penning discharge is still in a stable operation. Under the stable mode of Penning discharge there was always a stable vacuum arc ignition.

Nikolaev, A.G.; Schanin, P.M.; Yushkov, G.Yu. [High Current Electronics Inst., Tomsk (Russian Federation)] [and others

1995-12-31T23:59:59.000Z

213

Morphologies of the transition region in dissimilar austenitic-ferritic welds  

SciTech Connect (OSTI)

The morphology of the transition region in dissimilar austenitic-ferritic steel welds has been characterized using scanning and transmission electron microscopy and using energy-dispersive X-ray spectrometry. With increasing base metal carbon content, a martensite-like layer in the unmixed zone of this region diminishes or disappears, and a saw-tooth-like morphology extends form the partially melted zone into the weld. The number of weld interfaces also changes with variation in carbon content, from the double austenite/martensite-like and martensite-like/ferrite interfaces to a single austenite/martensite-like one. These variations are attributed to the local melting range of the base metal, which depends upon the carbon content, cooling rate, and alloy element segregation.

Pan, C.; Zhang, Z. [Wuhan Transportation Univ., Wuhan, Hubei (China). Lab. of Electron Microscopy] [Wuhan Transportation Univ., Wuhan, Hubei (China). Lab. of Electron Microscopy

1996-01-01T23:59:59.000Z

214

Dissimilar-welded failure analysis and development: Volume 6, Weld condition and remaining life assessment manual: Final report  

SciTech Connect (OSTI)

Step-by-step guidelines contained in a new engineering manual explain how to evaluate dissimilar metal weld loadings, assess the current state of damage, and predict remaining weld life. Suggested plant and operational modifications will help utility personnel identify root causes and avoid additional failures in a given boiler. Failure of dissimilar metal welds (DMWs) between the austenitic and ferritic steel tubing used in superheaters and reheaters constitutes a major cause of forced outages in fossil boilers. EPRI has undertaken a study of DMWs, reported in volumes 1-6 of this nine-volume series, to provide utilities with a systematic approach for identifying root causes, remedying identified problems, and estimating remaining DMW useful life. This manual follows the three-phase approach outlined in the EPRI guidelines for life extension (report CS-4778). The investigators subjected the samples to detailed metallurgical examination and established correlations among operating conditions, system stresses, and the extent of observed DMW cracking. These correlations were quantified in the PODIS computer code (prediction of damage in service code; EPRI report CS-4252, volume 7). The investigators documented this information in a manual explaining how to carry out life assessment of DMWs. These guidelines describe an analytic procedure that computes the current level of DMW damage based on operating temperature, the number and nature of cycles, and system stresses. They explain a procedure for supplementary destructive examinations to verify the analytic predictions. 10 refs., 20 figs., 2 tabs.

Not Available

1988-08-01T23:59:59.000Z

215

Intraluminal tissue welding for anastomosis  

DOE Patents [OSTI]

A method and device are provided for performing intraluminal tissue welding for anastomosis of a hollow organ. A retractable catheter assembly is delivered through the hollow organ and consists of a catheter connected to an optical fiber, an inflatable balloon, and a biocompatible patch mounted on the balloon. The disconnected ends of the hollow organ are brought together on the catheter assembly, and upon inflation of the balloon, the free ends are held together on the balloon to form a continuous channel while the patch is deployed against the inner wall of the hollow organ. The ends are joined or "welded" using laser radiation transmitted through the optical fiber to the patch. A thin layer of a light-absorbing dye on the patch can provide a target for welding. The patch may also contain a bonding agent to strengthen the bond. The laser radiation delivered has a pulse profile to minimize tissue damage.

Glinsky, Michael (Livermore, CA); London, Richard (Orinda, CA); Zimmerman, George (Lafayette, CA); Jacques, Steven (Portland, OR)

1998-10-27T23:59:59.000Z

216

Intraluminal tissue welding for anastomosis  

DOE Patents [OSTI]

A method and device are provided for performing intraluminal tissue welding for anastomosis of a hollow organ. A retractable catheter assembly is delivered through the hollow organ and consists of a catheter connected to an optical fiber, an inflatable balloon, and a biocompatible patch mounted on the balloon. The disconnected ends of the hollow organ are brought together on the catheter assembly, and upon inflation of the balloon, the free ends are held together on the balloon to form a continuous channel while the patch is deployed against the inner wall of the hollow organ. The ends are joined or ``welded`` using laser radiation transmitted through the optical fiber to the patch. A thin layer of a light-absorbing dye on the patch can provide a target for welding. The patch may also contain a bonding agent to strengthen the bond. The laser radiation delivered has a pulse profile to minimize tissue damage. 8 figs.

Glinsky, M.; London, R.; Zimmerman, G.; Jacques, S.

1998-10-27T23:59:59.000Z

217

Fracture toughness of thick section dissimilar electron beam weld joints  

SciTech Connect (OSTI)

Microstructural investigations as well as crack tip opening displacement (CTOD) fracture toughness test based on elastic-plastic fracture mechanics were performed on single pass, full penetration similar and dissimilar electron beam (EB) welds of 40 mm thick 316L type austenitic steel and high alloyed fine tempered martensitic 9Cr 1Mo Nb V (P91 -ASTM A213) steel. The latter modified steel has been developed to fill up the gap between 12Cr steel and austenitic stainless steels with respect to the high temperature properties and better weldability. Furthermore, it shows a small thermal expansion coefficient and is not susceptible to stress corrosion cracking like the austenitic steel. The weldment properties were evaluated by microstructural analysis, microhardness, Charpy V- notch impact, and by newly developed flat microtensile specimens (0.5 mm thick). The dissimilar EB weld metal and HAZ of P91 steel has been shown to be microstructurally and mechanically distinct from both austenitic and martenistic parent metals. The use of microsized rectangular tensile specimens provides unique solution to the problem of the mechanical property determination of the narrow EB weld joint. The HAZ of the 9Cr1Mo steel exhibits extremely poor CTOD toughness properties in as-welded condition at room temperature. The CTOD values obtained were believed to be represent the intrinsic property of this zone, since the distance of the crack tip to the austenitic steel part was too large to receive a stress relaxation effect from low strength side on the crack tip (by accommodating the applied strains in the high toughness, lower strength 316L plate).

Kocak, M.; Junghans, E.

1994-12-31T23:59:59.000Z

218

Vacuum Arc Ion Sources: Recent Developments and Applications  

SciTech Connect (OSTI)

The vacuum arc ion source has evolved over the past twenty years into a standard laboratory tool for the production of high current beams of metal ions, and is now used in a number of different embodiments at many laboratories around the world. The primary application of this kind of source has evolved to be ion implantation for material surface modification. Another important use is for injection of high current beams of heavy metal ions into the front ends of particle accelerators, and much excellent work has been carried out in recent years in optimizing the source for reliable accelerator application. The source also provides a valuable tool for the investigation of the fundamental plasma physics of vacuum arc plasma discharges. As the use of the source has grown and diversified, at the same time the ion source performance and operational characteristics have been improved in a variety of different ways also. Here we review the growth and status of vacuum arc ion sources around the world, and summarize some of the applications for which the sources have been used.

Brown, Ian; Oks, Efim

2005-05-01T23:59:59.000Z

219

EFFECT OF UNBROKEN LIGAMENTS ON STRESS CORROSION CRACKING BEHAVIOR OF ALLOY 82H WELDS  

SciTech Connect (OSTI)

Previously reported stress corrosion cracking (SCC) rates for Alloy 82H gas-tungsten-arc welds tested in 360 C water showed tremendous variability. The excessive data scatter was attributed to the variations in microstructure, mechanical properties and residual stresses that are common in welds. In the current study, however, re-evaluation of the SCC data revealed that the large data scatter was an anomaly due to erroneous crack growth rates inferred from crack mouth opening displacement (CMOD) measurements. Apparently, CMOD measurements provided reasonably accurate SCC rates for some specimens, but grossly overestimated rates in others. The overprediction was associated with large unbroken ligaments that often form in welds in the wake of advancing crack fronts. When ligaments were particularly large, they prevented crack mouth deflection, so apparent crack incubation times (i.e. period of time before crack advance commences) based on CMOD measurements were unrealistically long. During the final states of testing, ligaments began to separate allowing the crack mouth to open rather quickly. This behavior was interpreted as a rapid crack advance, but it actually reflects the ligament separation rate, not the SCC rate. Revised crack growth rates obtained in this study exhibit substantially less scatter than that previously reported. The effects of crack orientation and fatigue flutter loading on SCC rates in 82H welds are also discussed.

Mills, W.J. and Brown, C.M.

2003-02-20T23:59:59.000Z

220

Residual stress patterns in steel welds  

SciTech Connect (OSTI)

Neutron strain scanning of residual stress is a valuable nondestructive tool for evaluation of residual stress in welds. The penetrating characteristic of neutrons permits mapping of strain patterns with a spatial resolution approaching 1mm at depths of 20mm in steels. While the overall patterns of the residual stress tensor in a weld are understood, the detailed patterns depend on welding process parameters and the effects of solid state transformation. The residual strain profiles in two multi-pass austenitic welds and a ferritic steel weld are presented. The stress-free lattice parameters within the fusion zone and the adjacent heat affected zone in the two austenitic welds show that the interpretation of residual stress from strains are affected by welding parameters. An interpretation of the residual strain pattern in the ferritic steel plate can be made using the strain measurements of a Gleeble test bar which has undergone the solid state austenite decomposition.

Spooner, S.; Hubbard, C.R.; Wang, X.L.; David, S.A.; Holden, T.M. [Oak Ridge National Lab., TN (United States); Root, J.H.; Swainson, I. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

1994-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding  

E-Print Network [OSTI]

Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding- turing processes involving plastic deformation of metallic materials. The main attraction to this model (e.g., those associated with the influence of plastic deformation, rate of deformation

Grujicic, Mica

222

Application of electrostatic Langmuir probe to atmospheric arc plasmas producing nanostructures  

SciTech Connect (OSTI)

The temporal evolution of a high pressure He arc producing nanotubes was considered and the Langmuir probe technique was applied for plasma parameter measurements. Two modes of arc were observed: cathodic arc where discharge is supported by erosion of cathode material and anodic arc which is supported by ablation of the anode packed with carbon and metallic catalysts in which carbon nanotubes are synthesized. Voltage-current (V-I) characteristics of single probes were measured and unusually low ratio of saturation current on positively biased probe to that on negatively biased of about 1-4 was observed. This effect was explained by increase of measured current at the negatively biased probe above the level of ion saturation current due to secondary electron emission from the probe surface. Since utilization of standard collisionless approach to determine plasma parameters from the measured V-I characteristic is not correct, the electron saturation current was used to estimate the plasma density.

Shashurin, A.; Li, J.; Zhuang, T.; Keidar, M. [Department of Mechanical and Aerospace Engineering, School of Engineering and Applied Science, George Washington University, Washington, District of Columbia 20052 (United States); Beilis, I. I. [School of Electrical Engineering, Tel Aviv University, Ramat Aviv 69978 (Israel)

2011-07-15T23:59:59.000Z

223

Characterization of arcs in frequency domain  

SciTech Connect (OSTI)

Arc detection systems are developed for ICRH on ITER to prevent arcs from damaging the RF components. One of the detectors, the Sub-Harmonic Arc Detector (SHAD) is based on the detection of the frequencies emitted in the MHz range by arcs [R1]. To ensure the high level of reliability required for this safety system, it is necessary to demonstrate that these frequencies present a signal with a Signal to Noise Ratio high enough to be detected under the wide range of operational conditions (frequency, power, configuration) and for the different types of arcs that can appear in the feeding lines and on the antennas (vacuum arc, glow discharge, multipactor-induced discharge). For each type of arc, we analyze the evolution of the frequency spectrum relative to the evolution of other electrical parameters (reflected power, voltage)

D'Inca, R.; Siegl, G.; Faugel, H.; Braun, F.; Eckert, B.; Bobkov, V. [Max Planck Institut fuer Plasmaphysik, Garching, Germany, EURATOM Association (Germany); El Khaldi, M. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Noterdaeme, J.-M. [Max Planck Institut fuer Plasmaphysik, Garching, Germany, EURATOM Association (Germany); Gent University, EESA Department (Belgium)

2009-11-26T23:59:59.000Z

224

Remote Opening and Sealing of Metal Tubes  

Science Journals Connector (OSTI)

``One?shot'' methods of opening and sealing metal tubes are described. These methods were developed for taking high altitude atmospheric samples in metal bottles carried aloft by rockets and are performed by pyrotechnic means. The sealing is done by cold welding.

L. T. Loh; H. W. Neill; M. H. Nichols; E. A. Wenzel

1952-01-01T23:59:59.000Z

225

Filters for cathodic arc plasmas  

DOE Patents [OSTI]

Cathodic arc plasmas are contaminated with macroparticles. A variety of magnetic plasma filters has been used with various success in removing the macroparticles from the plasma. An open-architecture, bent solenoid filter, with additional field coils at the filter entrance and exit, improves macroparticle filtering. In particular, a double-bent filter that is twisted out of plane forms a very compact and efficient filter. The coil turns further have a flat cross-section to promote macroparticle reflection out of the filter volume. An output conditioning system formed of an expander coil, a straightener coil, and a homogenizer, may be used with the magnetic filter for expanding the filtered plasma beam to cover a larger area of the target. A cathodic arc plasma deposition system using this filter can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

Anders, Andre (Albany, CA); MacGill, Robert A. (Richmond, CA); Bilek, Marcela M. M. (Engadine, AU); Brown, Ian G. (Berkeley, CA)

2002-01-01T23:59:59.000Z

226

The effect of electromagnetic forces on the penetrator formation during high-frequency electric resistance welding  

Science Journals Connector (OSTI)

During high-frequency electric resistance welding (HF-ERW), the electromagnetic force induced by the high-frequency electric current was studied to improve the understanding of penetrator formation mechanism. ERW melting zone behavior is investigated by the cinematography and the three-dimensional numerical analysis of electromagnetic field around molten metal bridge. Based on the results, the penetrator formation is mainly influenced by the narrow gap shape, the variation of electromagnetic forces along the narrow gap, the molten metal bridge traveling speed, and the second bridge formation frequency. Electromagnetic force acting on the molten metal bridge is rapidly decreasing as the bridge is traveling away from the apex point. The ‘comet’ shape narrow gap produced by the variation of Lorentz forces makes the bridge pushing pressure decrease. Due to the decrease of electromagnetic force and pushing pressure, the sweeping speed of molten metal bridge slows down until the bridge reaches the welding point. Previous molten metal bridge traveling is arrested when the next bridge is formed before the previous bridge arrives at the welding point. Thus, the molten metal and oxide are refilled into the narrow gap due to the capillary force and then remained as a penetrator. According to the analysis of penetrator formation mechanism, the new penetrator formation model is proposed.

Choong-Myeong Kim; Jung-Kyu Kim

2009-01-01T23:59:59.000Z

227

In-service repair of main pipelines by welding  

Science Journals Connector (OSTI)

A new approach to the repair of main pipelines by welding without removing them from service ... failure risk; safety of welding works on pipeline under pressure; use of different variants of repair by welding; s...

V. I. Makhnenko; V. S. But; O. I. Oleinik

2009-09-01T23:59:59.000Z

228

Friction stir welding and processing has come a long way since the heady days of the pioneering work done at TWI in Cambridge some two decades ago. The FSWP 2010 conference held in Lille,  

E-Print Network [OSTI]

% of research papers on FSW published since 2008 are on dissimilar metal joining; this is a large increase whenEditorial Friction stir welding and processing has come a long way since the heady days dealt with welding are included in this special issue of STWJ. All of these papers went through

Cambridge, University of

229

Additive manufacturing with friction welding and friction deposition processes  

Science Journals Connector (OSTI)

Most of the commercially available additive manufacturing processes that are meant for fabrication of fully dense metallic parts involve melting and solidification. Consequently, these processes suffer from a variety of metallurgical problems. Processes that can facilitate material addition in solid-state are therefore ideally suited for additive manufacturing. In this work, we explore two new solid-state processes, viz. friction welding and friction deposition, for additive manufacturing. Stainless steel samples produced using these processes showed excellent layer bonding and Z-direction tensile properties. The authors believe that these processes are uniquely capable and can offer significant benefits over existing commercial additive manufacturing processes.

J.J.S. Dilip; G.D. Janaki Ram; B.E. Stucker

2012-01-01T23:59:59.000Z

230

Fabrication Flaws in Reactor Pressure Vessel Repair Welds  

SciTech Connect (OSTI)

This paper describes the fabrication flaw distribution and characterization in the repair weld metal of reactor pressure vessels. This work indicates that the large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the repair ends. Parametric analysis using an exponential fit is performed on the data. A description of repair flaw morphology is provided. Fabrication flaws in repairs are characterized using high sensitivity nondestructive ultrasonic testing, validation by other nondestructive evaluation (NDE) techniques, and complemented by destructive testing.

Schuster, George J.; Doctor, Steven R.

2007-12-01T23:59:59.000Z

231

Method and device for frictional welding  

DOE Patents [OSTI]

A method for friction welding that produces a seal having essentially no gas porosity, comprises two rotationally symmetric, generally cylindrical members, spaced apart and coaxially aligned, that are rotated with respect to each other and brought together under high pressure. One member is preferably a generally cylindrical cannister that stores uranium within its hollow walls. The other member is preferably a generally cylindrical, hollow weld ring. An annular channel formed in the weld ring functions as an internal flash trap and is uniquely designed so that substantially all of the welding flash generated from the friction welding is directed into the channel`s recessed bottom. Also, the channel design limits distortion of the two members during the friction welding, process, further contributing to the complete seal that is obtained.

Peacock, H.B.

1991-01-01T23:59:59.000Z

232

Method and device for frictional welding  

DOE Patents [OSTI]

A method for friction welding that produces a seal having essentially no gas porosity, comprises two rotationally symmetric, generally cylindrical members, spaced apart and coaxially aligned, that are rotated with respect to each other and brought together under high pressure. One member is preferably a generally cylindrical cannister that stores uranium within its hollow walls. The other member is preferably a generally cylindrical, hollow weld ring. An annular channel formed in the weld ring functions as an internal flash trap and is uniquely designed so that substantially all of the welding flash generated from the friction welding is directed into the channel's recessed bottom. Also, the channel design limits distortion of the two members during the friction welding process, further contributing to the complete seal that is obtained.

Peacock, Harold B. (867 N. Belair Rd., Evans, GA 30809)

1992-01-01T23:59:59.000Z

233

Technical Letter Report Assessment of Ultrasonic Phased Array Testing for Cast Austenitic Stainless Steel Pressurizer Surge Line Piping Welds and Thick Section Primary System Cast Piping Welds JCN N6398, Task 2A  

SciTech Connect (OSTI)

Research is being conducted for the NRC at PNNL to assess the effectiveness and reliability of advanced NDE methods for the inspection of LWR components. The scope of this research encompasses primary system pressure boundary materials including cast austenitic stainless steels (CASS), dissimilar metal welds (DMWs), piping with corrosion-resistant cladding, weld overlays, and far-side examinations of austenitic piping welds. A primary objective of this work is to evaluate various NDE methods to assess their ability to detect, localize, and size cracks in coarse-grained steel components. This interim technical letter report (TLR) provides a synopsis of recent investigations at PNNL aimed at evaluating the capabilities of phased-array (PA) ultrasonic testing (UT) methods as applied to the inspection of CASS welds in nuclear reactor piping. A description of progress, recent developments and interim results are provided.

Diaz, Aaron A.; Denslow, Kayte M.; Cinson, Anthony D.; Morra, Marino; Crawford, Susan L.; Prowant, Matthew S.; Cumblidge, Stephen E.; Anderson, Michael T.

2008-07-21T23:59:59.000Z

234

Microsoft Word - DOE-ID-14-067 MesoCoat EC B3-6.doc  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Title: Functionally Gradient Transition Joint for Dissimilar Metal Welding using Plasma Arc Lamps- MesoCoat, Inc. SECTION B. Project Description MesoCoat, Inc. will conduct...

235

An interchangeable-cathode vacuum arc plasma source David K. Olson,a  

E-Print Network [OSTI]

design based on metal vapor vacuum arc MeVVA concepts is employed as a plasma source for a study of a 7 using a boron-carbide disk as the cathode target. The design is simplified from typical designs with a proton beam. We create our 7 Be on the surface of a sample of enriched boron carbide. Because 7

Hart, Gus

236

Welding Cutting and Brazing Assessment Plan Assessment plan - Developed By NNSA/Nevada Site Office Facility Representative Division  

Broader source: Energy.gov (indexed) [DOE]

WELDING, CUTTING AND BRAZING WELDING, CUTTING AND BRAZING Assessment Plan NNSA/Nevada Site Office Facility Representative Division Performance Objective: This assessment is to verify hot work requirements associated with welding, cutting, burning, brazing, grinding and other spark- or flame-producing operations have been implemented. Verify that the requirements implemented are appropriate for preventing loss of life and property from fire, and personal injury from contact with or exposure to molten metals, vapors, radiant energy, injurious rays and sparks. Criteria: Establish designated area in which routine and repetitive welding, cutting, and other spark- or flame producing operations are conducted [1910.252(a)(2)(iv),1910.252(a)(2)(vi)(A), 1910.252(a)(2)(xv), General Requirements].

237

Nd:YAG laser welding aluminum alloys  

SciTech Connect (OSTI)

Autogenous Nd:YAG laser welding wrought 4047, 1100, 3003, 2219, 5052, 5086, 5456, and 6061 and cast A356 aluminum alloys to cast A356 aluminum alloy in restrained annular weld joints was investigated. The welds were 12.7 mm (0.375 in.) and 9.5 mm (0.375 in.) diameter with approximately 0.30 mm (0.012 in.) penetration. This investigation determined 4047 aluminum alloy to be the optimum alloy for autogenous Nd:YAG laser welding to cast A356 aluminum alloy. This report describes the investigation and its results.

Jimenez, E. Jr.

1992-02-01T23:59:59.000Z

238

A multi-bead overlapping model for robotic wire and arc additive manufacturing (WAAM)  

Science Journals Connector (OSTI)

Abstract Wire and arc additive manufacturing (WAAM) is a promising alternative to traditional subtractive manufacturing for fabricating large aerospace components that feature high buy-to-fly ratio. Since the WAAM process builds up a part with complex geometry through the deposition of weld beads on a layer-by-layer basis, it is important to model the geometry of a single weld bead as well as the multi-bead overlapping process in order to achieve high surface quality and dimensional accuracy of the fabricated parts. This study firstly builds models for a single weld bead through various curve fitting methods. The experimental results show that both parabola and cosine functions accurately represent the bead profile. The overlapping principle is then detailed to model the geometry of multiple beads overlapping together. The tangent overlapping model (TOM) is established and the concept of the critical centre distance for stable multi-bead overlapping processes is presented. The proposed TOM is shown to provide a much better approximation to the experimental measurements when compared with the traditional flat-top overlapping model (FOM). This is critical in process planning to achieve better geometry accuracy and material efficiency in additive manufacturing.

Donghong Ding; Zengxi Pan; Dominic Cuiuri; Huijun Li

2015-01-01T23:59:59.000Z

239

Welding shield for coupling heaters  

DOE Patents [OSTI]

Systems for coupling end portions of two elongated heater portions and methods of using such systems to treat a subsurface formation are described herein. A system may include a holding system configured to hold end portions of the two elongated heater portions so that the end portions are abutted together or located near each other; a shield for enclosing the end portions, and one or more inert gas inlets configured to provide at least one inert gas to flush the system with inert gas during welding of the end portions. The shield may be configured to inhibit oxidation during welding that joins the end portions together. The shield may include a hinged door that, when closed, is configured to at least partially isolate the interior of the shield from the atmosphere. The hinged door, when open, is configured to allow access to the interior of the shield.

Menotti, James Louis (Dickinson, TX)

2010-03-09T23:59:59.000Z

240

Temporal Development of Ion Beam Mean Charge State in PulsedVacuum Arc Ion Sources  

SciTech Connect (OSTI)

Vacuum arc ion sources, commonly also known as "Mevva" ionsources, are used to generate intense pulsed metal ion beams. It is knownthat the mean charge state of the ion beam lies between 1 and 4,depending on cathode material, arc current, arc pulse duration, presenceor absence of magnetic field at the cathode, as well background gaspressure. A characteristic of the vacuum arc ion beam is a significantdecrease in ion charge state throughout the pulse. This decrease can beobserved up to a few milliseconds, until a "noisy" steady-state value isestablished. Since the extraction voltage is constant, a decrease in theion charge state has a proportional impact on the average ion beamenergy. This paper presents results of detailed investigations of theinfluence of arc parameters on the temporal development of the ion beammean charge state for a wide range of cathode materials. It is shown thatfor fixed pulse duration, the charge state decrease can be reduced bylower arc current, higher pulse repetition rate, and reduction of thedistance between cathode and extraction region. The latter effect may beassociated with charge exchange processes in the dischargeplasma.

Oks, Efim M.; Yushkov, Georgy Yu.; Anders, Andre

2007-06-21T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Characterization of solid-phase welds between Ti-6Al-2Sn-4Zr-2Mo-0. 01Si and Ti-13. 5A1-21. 5Nb titanium aluminide  

SciTech Connect (OSTI)

Dissimilar-alloy welds have been produced between Ti-6Al-2Sn-4Zr-2Mo-0.1Si (wt.%) and Ti-13.5Al-21.5Nb (wt.%) titanium aluminide using three different solid-phase welding processes that create significantly different thermo-mechanical conditions at the weld interface. Exposure to supertransus temperatures, appreciable deformation and rapid cooling of the weld interface region during linear-friction welding promote dynamic recrystallization of beta grains and beta decomposition to fine martensitic products. In contrast, diffusion welding at temperatures below the base metal beta transus temperatures and at relatively low pressures minimizes deformation and microstructural variations in the weld interface region relative to the unaffected base metal. During capacitor-discharge resistance spot welding, extremely rapid heating of the weld interface region to near-solidus temperatures, and subsequent rapid cooling, result in the formation of a metastable, ordered-beta microstructure in the Ti-13.5ASl-21.5Nb and fine alpha-prime martensite in the Ti-6Al-2Sn-4Zr-2Mo-0.1Si.

Baeslack, W.A. III; Juhas, M.; Fraser, H.L. (Ohio State Univ., Columbus, OH (United States)); Broderick, T.F. (Wright Labs., Wright Patterson AFB, OH (United States). Materials Directorate)

1994-12-01T23:59:59.000Z

242

Multi-mode ultrasonic welding control and optimization  

DOE Patents [OSTI]

A system and method for providing multi-mode control of an ultrasonic welding system. In one embodiment, the control modes include the energy of the weld, the time of the welding process and the compression displacement of the parts being welded during the welding process. The method includes providing thresholds for each of the modes, and terminating the welding process after the threshold for each mode has been reached, the threshold for more than one mode has been reached or the threshold for one of the modes has been reached. The welding control can be either open-loop or closed-loop, where the open-loop process provides the mode thresholds and once one or more of those thresholds is reached the welding process is terminated. The closed-loop control provides feedback of the weld energy and/or the compression displacement so that the weld power and/or weld pressure can be increased or decreased accordingly.

Tang, Jason C.H.; Cai, Wayne W

2013-05-28T23:59:59.000Z

243

Microstructural Characterization of 6061 Aluminum to 304L Stainless Steel Inertia Welds  

SciTech Connect (OSTI)

'Microstructural characterization of 6061-T6 aluminum-to-Type 304L stainless steel inertia welds provided a technical basis to conclude that transition joints fabricated from such welds should satisfactorily contain helium/hydrogen gas mixtures. This conclusion is based on the lack of semi-continuous alignments of particles and/or inclusions at, or near, the aluminum-to-stainless steel interface. These dissimilar metal transition joints play a key role in the operation of an accelerator driven, spallation neutron source designed for the production of tritium. The Accelerator Production of Tritium system will produce tritium through neutron interactions with 3He gas contained in water-cooled, 6061-T6 aluminum pressure tubes. Current design concepts include thousands of thin-walled pressure tubes distributed throughout a number of aluminum-clad, lead-filled, blanket modules. The aluminum pressure tubes are connected to a tritium extraction and purification system through a stainless steel manifold. The transition from aluminum to stainless steel is made via transition joints machined from the aluminum-to-stainless steel inertia welds. The paper describes the baseline microstructural characterization of the welds, including optical, scanning and transmission electron microscopy and uses that characterization to evaluate potential gas leakage across the weld.'

Dunn, K.A.

1999-09-29T23:59:59.000Z

244

Plasma of Electric Arc Discharge between Melted Electrodes  

Science Journals Connector (OSTI)

Plasma of electric arc discharge between melted electrodes was experimentally investigated. Diagnostics of electric arc plasma was carried out. Optical emission and ... in plasma tends to be located at the arc ax...

A.N. Veklich; I.L. Babich

2001-01-01T23:59:59.000Z

245

High temperature low-cycle fatigue of friction welded joints - type 304-304 stainless steel and alloy 718-718 nickel base superalloy  

SciTech Connect (OSTI)

This paper assesses the high-temperature low-cycle fatigue of the Type 304 stainless steel and Alloy 718 superalloy friction-welded joints. Strain controlled low-cycle fatigue tests for 304-304 and 718-718 friction-welded specimens were carried out at 923 K in air to obtain the fatigue strength of the joints. These materials were selected as the cyclic hardening and softening materials, respectively. The 304-304 welded specimens showed inferior fatigue strength in comparison with the base metal while the 718-718 specimens exhibited fatigue strength equivalent to that of the base metal. The difference in the fatigue strength between the two materials is discussed from the viewpoint of the cyclic deformation behavior and strain reduction at weld interface.

Wakai, T. (Power Reactor and Nuclear Fuel Development Corp., Ibaraki (Japan). Oarai Engineering Center); Sakane, M.; Ohnami, M. (Ritsumeikan Univ., Kyoto (Japan). Dept. of Mechanical Engineering); Okita, K. (Hyogo Prefectural Inst. of Industrial Research, Miki (Japan). Technical Center for Machinery and Metals); Fukuchi, Y. (Hyogo Prefectural Inst. of Industrial Research, Kobe (Japan))

1993-01-01T23:59:59.000Z

246

Microsoft Word - DOE-ID-12-041 INL EC B3-6.doc  

Broader source: Energy.gov (indexed) [DOE]

1 1 SECTION A. Project Title: Monitoring and Control of the Hybrid Laser-Gas Metal Arc Welding Process - Idaho National Laboratory SECTION B. Project Description This project will investigate a promising welding process that combines gas metal-arc welding and laser beam welding into Hybrid Las - Gas Metal-Arc Welding. The objectives of this project are to: ï‚· Develop and demonstrate a prototype system base on a number of sensing and diagnostic tools to monitor and provide real- time weld process control information, including ultrasonics to monitor subsurface weld pool geometry and defect formation ï‚· Record and analyze welding and defect formation ï‚· Develop other potential sensors for laser/weld interaction ï‚· Develop real-time post weld examination capabilities

247

The Temperature of the Copper Arc  

Science Journals Connector (OSTI)

...Laboratory, General Electric Company. | Journal Article...TEMPERATURE OF THE COPPER ARC By C. G. SUITS RESEARCH LABORATORY, GENERAL ELECTRIC COMPANY Read before the...figure 1, where Fis an arc burning between the electrodes...experiment is a condensed discharge between the electrode...

C. G. Suits

1935-01-01T23:59:59.000Z

248

Increasing the length of single-wall carbon nanotubes in a magnetically enhanced arc discharge  

SciTech Connect (OSTI)

It is demonstrated that a magnetic field has a profound effect on the length of a single-wall carbon nanotube (SWCNT) synthesized in the arc discharge. The average length of SWCNT increases by a factor of 2 in discharge with magnetic field as compared with the discharge without magnetic field, and the yield of long nanotubes with lengths above 5 {mu}m also increases. A model of SWCNT growth on metal catalyst in arc plasma was developed. Monte-Carlo simulations confirm that the increase of the plasma density in the magnetic field leads to an increase in the nanotube growth rate and thus leads to longer nanotubes.

Keidar, Michael [Department of Mechanical and Aerospace Engineering, George Washington University, Washington, District of Columbia 20052 (United States); Levchenko, Igor; Ostrikov, Kostya [Plasma Nanoscience, School of Physics, The University of Sydney, Sydney, New South Wales 2006 (Australia); Arbel, Tamir [Department of Material Science, University of Michigan, Ann Arbor, Michigan 48109 (United States); Alexander, Myriam [Department of Geophysical Science, University of Chicago, Chicago, Illinois 60637 (United States); Waas, Anthony M. [Department of Aerospace Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2008-01-28T23:59:59.000Z

249

Local arc discharge mechanism and requirements of power supply in micro-arc oxidation of magnesium alloy  

Science Journals Connector (OSTI)

To study the requirements of the power supply in micro-arc oxidation (MAO) of magnesium alloy, many experiments ... . Based on the experimental results and electric arc theory, the separate local arc discharge me...

Ming Chen; Yuezhou Ma; Yuan Hao

2010-03-01T23:59:59.000Z

250

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Hawke, R.S.

1985-08-05T23:59:59.000Z

251

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile. 2 figs.

Hawke, R.S.

1987-11-17T23:59:59.000Z

252

Low voltage arc formation in railguns  

DOE Patents [OSTI]

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Hawke, Ronald S. (Livermore, CA)

1987-01-01T23:59:59.000Z

253

Nitrogen Control in Electric Arc Furnace Steelmaking by Direct...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Nitrogen Control in Electric Arc Furnace Steelmaking by Direct Reduced Iron Fines Injection Nitrogen Control in Electric Arc Furnace Steelmaking by Direct Reduced Iron Fines...

254

Tribological performance of hybrid filtered arc-magnetron coatings...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Tribological performance of hybrid filtered arc-magnetron coatings - Part I: Coating deposition process and basic coating Tribological performance of hybrid filtered arc-magnetron...

255

The robustness of dynamic vehicle performance to spot weld failures  

Science Journals Connector (OSTI)

Spot welds are the dominant joining method in the vehicle assembly process. As the automated assembly process is not perfect, some spot welds may be absent when the vehicle leaves the assembly line. Furthermore, spot welds are highly susceptible to fatigue, ... Keywords: Failure, Fatigue, Finite element analysis, Robustness, Spot welds, Structural dynamics

S. Donders; M. Brughmans; L. Hermans; C. Liefooghe; H. Van der Auweraer; W. Desmet

2006-05-01T23:59:59.000Z

256

Effect of activity differences on hydrogen migration in dissimilar titanium alloy welds  

SciTech Connect (OSTI)

The effect of alloy composition on hydrogen activity was measured for seven titanium alloys as a means to determine the tendency for hydrogen migration within dissimilar metal welds. The alloys were: Ti-CP (unalloyed Ti), Ti-3Al-2.5V, Ti-3Al-2.5V-3Zr, Ti-3Al-2Nb-1Ta, Ti-6Al, Ti-6Al-4V, and Ti-6Al-2Nb-1Ta-0.8Mo. Hydrogen pressure-hydrogen concentration relationships were determined for temperatures from 600 C to 800 C and hydrogen concentrations up to approximately 3.5 at. pct (750 wppm). Fusion welds were made between Ti-CP and Ti-CP and between Ti-CP and Ti-6Al-4V to observe directly the hydrogen redistribution in similar and dissimilar metal couples. Hydrogen activity was found to be significantly affected by alloying elements, particularly Al in solid solution. At a constant Al content and temperature, an increase in the volume fraction of {beta} reduced the activity of hydrogen in {alpha}-{beta} alloys. Activity was also found to be strongly affected by temperature. The effect of temperature differences on hydrogen activity was much greater than the effects resulting from alloy composition differences at a given temperature. Thus, hydrogen redistribution should be expected within similar metal couples subjected to extreme temperature gradients, such as those peculiar to fusion welding. Significant hydrogen redistribution in dissimilar alloy weldments also can be expected for many of the compositions in this study. Hydride formation stemming from these driving forces was observed in the dissimilar couple fusion welds. In addition, a basis for estimating hydrogen migration in titanium welds, based on hydrogen activity data, is described.

Kennedy, J.R.; Adler, P.N. [Grumman Corp., Bethpage, NY (United States). Corporate Research Center; Margolin, H. [Polytechnic Univ., Brooklyn, NY (United States). Dept. of Materials Science and Engineering

1993-12-01T23:59:59.000Z

257

Theoretical analysis of ARC constriction  

SciTech Connect (OSTI)

The physics of the thermionic converter is governed by strong electrode-plasma interactions (emissions surface scattering, charge exchange) and weak interactions (diffusion, radiation) at the maximum interelectrode plasma radius. The physical processes are thus mostly convective in thin sheaths in front of the electrodes and mostly diffusive and radiative in the plasma bulk. The physical boundaries are open boundaries to particle transfer (electrons emitted or absorbed by the electrodes, all particles diffusing through some maximum plasma radius) and to convective, conductive and radiative heat transfer. In a first approximation the thermionic converter may be described by a one-dimensional classical transport theory. The two-dimensional effects may be significant as a result of the sheath sensitivity to radial plasma variations and of the strong sheath-plasma coupling. The current-voltage characteristic of the converter is thus the result of an integrated current density over the collector area for which the boundary conditions at each r determine the regime (ignited/unignited) of the local current density. A current redistribution strongly weighted at small radii (arc constriction) limits the converter performance and opens questions on constriction reduction possibilities. The questions addressed are the followng: (1) what are the main contributors to the loss of current at high voltage in the thermionic converter; and (2) is arc constriction observable theoretically and what are the conditions of its occurrence. The resulting theoretical problem is formulated and results are given. The converter electrical current is estimated directly from the electron and ion particle fluxes based on the spatial distribution of the electron/ion density n, temperatures T/sub e/, T/sub i/, electrical voltage V and on the knowledge of the transport coefficients. (WHK)

Stoenescu, M.L.; Brooks, A.W.; Smith, T.M.

1980-12-01T23:59:59.000Z

258

Deformation behavior of laser welds in high temperature oxidation resistant Fe–Cr–Al alloys for fuel cladding applications  

Science Journals Connector (OSTI)

Abstract Ferritic-structured Fe–Cr–Al alloys are being developed and show promise as oxidation resistant accident tolerant light water reactor fuel cladding. This study focuses on investigating the weldability and post-weld mechanical behavior of three model alloys in a range of Fe–(13–17.5)Cr–(3–4.4)Al (wt.%) with a minor addition of yttrium using modern laser-welding techniques. A detailed study on the mechanical performance of bead-on-plate welds using sub-sized, flat dog-bone tensile specimens and digital image correlation (DIC) has been carried out to determine the performance of welds as a function of alloy composition. Results indicated a reduction in the yield strength within the fusion zone compared to the base metal. Yield strength reduction was found to be primarily constrained to the fusion zone due to grain coarsening with a less severe reduction in the heat affected zone. For all proposed alloys, laser welding resulted in a defect free weld devoid of cracking or inclusions.

Kevin G. Field; Maxim N. Gussev; Yukinori Yamamoto; Lance L. Snead

2014-01-01T23:59:59.000Z

259

Neutron and x-ray scattering studies of the metallurgical condition and residual stresses in Weldalite welds  

SciTech Connect (OSTI)

Weldalite is a lithium-containing aluminum alloy which is being considered for aerospace applications because its favorable strength-to-weight ratio. Successful welding of this alloy depends on the control of the metallurgical condition and residual stresses in the heat affected zone. Neutron and x-ray scattering methods of residual stress measurement were applied to plasma arc welds made in aluminum-lithium alloy test panels as part of an evaluation of materials for use in welded structures. In the course of these studies discrepancies between x-ray and neutron results from the heat affected zone (HAZ) of the weld were found. Texture changes and recovery from the cold work, indicated in peak widths, were found in the HAZ as well. The consideration of x-ray and neutron results leads to the conclusion that there is a change in solute composition which modifies the d-spacings in the HAZ which affects the neutron diffraction determination of residual stresses. The composition changes give the appearance of significant compressive strains in the HAZ. This effect and sharp gradients in the texture give severe anomalies in the neutron measurement of residual stress. The use of combined x-ray and neutron techniques and the solution to the minimizing of the neutron diffraction anomalies are discussed.

Spooner, S. [Oak Ridge National Lab., TN (United States); Pardue, E.B.S. [Technology for Energy Corp., Knoxville, TN (United States)

1995-12-31T23:59:59.000Z

260

An Application of Augmented Reality (AR) in the Teaching of an Arc Welding Robot  

E-Print Network [OSTI]

Augmented Reality (AR) is an emerging technology that utilizes computer vision methods to overlay virtual objects onto the real world scene so as to make them appear to co-exist with the real objects. Its main objective ...

Chong, J. W. S.

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Double-Sided Arc Welding of AZ31B Magnesium Alloy Sheet.  

E-Print Network [OSTI]

??Magnesium alloys are of interest to the automotive industry because of their high specific strength and potential to reduce vehicle weight and fuel consumption. In… (more)

Shuck, Gerald

2013-01-01T23:59:59.000Z

262

Microstructures and mechanical properties of Ti-6Al-4V welds with filler additions of tantalum and FS85  

SciTech Connect (OSTI)

Many applications in the nuclear industry require that titanium alloys be welded to refractory metal alloys. Because of the widely dissimilar properties of these materials, the homogeneity of the fusion zone os of particular concern. To address this issue, a study was conducted to characterize the fusion zones of Ti-6Al-4V welds made with filler additions of tantalum and FS85 (Nb-28Wt%Ta-10wt%W-1wt%Zr). A goal of this study was to evaluate the feasibility of making microstructural predictions based on calculated fusion zone electron/atom (e/a) ratios. The welds were made by placing tantalum or FS85 shims between two pieces of 2.5 mm (0.1 in.) thick Ti-6Al-4V and making an electron beam weld along the length of the shim. With complete mixing, these shims were expected to produce fusion zone e/a ratios of 3.63{emdash}4.14 for the Ta series and 3.63{emdash}4.06 for the FS85 series, and microstructures consisting of {alpha}`, {alpha}`, and perhaps {omega}. The weld macro- and microstructures were characterized using optical and electron microscopy, energy-dispersive spectroscopy, and x-ray diffraction. The mechanical properties of the welds were assessed using transverse and all-weld-metal tensile tests. The results showed a general increase in strength and decrease in ductility with increasing {beta} stabilizer level. As a result of this study, parameters were developed to increase the fusion zone size and increase mixing of the components. This work was performed at Sandia National Laboratories, supported by the U.S. Department of Energy under contract number DE-AC04-76DR00789, and at Los Alamos National Laboratory under contract number W-7405-ENG-36.

Damkroger, B.K.; Dixon, R.D.; Cotton, J.D.

1994-12-31T23:59:59.000Z

263

Automated generation of weld path trajectories.  

SciTech Connect (OSTI)

AUTOmated GENeration of Control Programs for Robotic Welding of Ship Structure (AUTOGEN) is software that automates the planning and compiling of control programs for robotic welding of ship structure. The software works by evaluating computer representations of the ship design and the manufacturing plan. Based on this evaluation, AUTOGEN internally identifies and appropriately characterizes each weld. Then it constructs the robot motions necessary to accomplish the welds and determines for each the correct assignment of process control values. AUTOGEN generates these robot control programs completely without manual intervention or edits except to correct wrong or missing input data. Most ship structure assemblies are unique or at best manufactured only a few times. Accordingly, the high cost inherent in all previous methods of preparing complex control programs has made robot welding of ship structures economically unattractive to the U.S. shipbuilding industry. AUTOGEN eliminates the cost of creating robot control programs. With programming costs eliminated, capitalization of robots to weld ship structures becomes economically viable. Robot welding of ship structures will result in reduced ship costs, uniform product quality, and enhanced worker safety. Sandia National Laboratories and Northrop Grumman Ship Systems worked with the National Shipbuilding Research Program to develop a means of automated path and process generation for robotic welding. This effort resulted in the AUTOGEN program, which has successfully demonstrated automated path generation and robot control. Although the current implementation of AUTOGEN is optimized for welding applications, the path and process planning capability has applicability to a number of industrial applications, including painting, riveting, and adhesive delivery.

Sizemore, John M. (Northrop Grumman Ship Systems); Hinman-Sweeney, Elaine Marie; Ames, Arlo Leroy

2003-06-01T23:59:59.000Z

264

Magnetic-cusp, cathodic-arc source  

DOE Patents [OSTI]

A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission. 3 figs.

Falabella, S.

1995-11-21T23:59:59.000Z

265

Welding of uranium and uranium alloys  

SciTech Connect (OSTI)

The major reported work on joining uranium comes from the USA, Great Britain, France and the USSR. The driving force for producing this technology base stems from the uses of uranium as a nuclear fuel for energy production, compact structures requiring high density, projectiles, radiation shielding, and nuclear weapons. This review examines the state-of-the-art of this technology and presents current welding process and parameter information. The welding metallurgy of uranium and the influence of microstructure on mechanical properties is developed for a number of the more commonly used welding processes.

Mara, G.L.; Murphy, J.L.

1982-03-26T23:59:59.000Z

266

Inertia-friction welding of particulate-reinforced aluminum matrix composites  

SciTech Connect (OSTI)

Aluminum metal-matrix composites (Al-MMC) are rapidly becoming materials of choice for many aerospace, automotive, recreational sports, and microelectronic applications. The attractive features of these materials include high specific strength and stiffness, a low coefficient of thermal expansion and enhanced wear characteristics relative to monolithic aluminum alloys. The effective engineering application of Al-MMC will commonly require their joining beth to themselves, to dissimilar Al-MMC, and to monolithic aluminum alloys. In the present work, dissimilar-alloy inertia-friction welds were produced between a 6061-T6 Al-MMC tube reinforced with l0 v/o Al{sub x}O{sub 3} particles (W6A.l0A-T6) and a modified A356 case MMC bar reinforced with 20 v/o SiC particles (F3S.20S), or a monolithic 6061-T6511 aluminum alloy bar. In Phase I, a fractional-factorial test matrix was statistically designed and performed to evaluate the effects of flywheel speed and axial pressure on the weld integrity, microstructure, hardness, tensile and torsion strengths and fracture behavior. In Phase 2, the effects of pre-weld machining of the solid bar on weld alignment and mechanical properties were evaluated. inertia-friction welding was shown to be effective for the joining of alumina particulate-reinforced composites to monolithic aluminum and to SiC-particulate reinforced aluminum. High-integrity joints exhibiting a defect-free joint interface with varying degrees of base alloy intermixing were produced at optimum parameter settings. Tensile and torsional strength joint efficiencies for the alumina-particulate MMC to monolithic aluminum alloy welds exceeded 80% and 75%, respectively, with tensile strength maximized with high axial pressure and flywheel speed, and torsional strength maximized at both medium and high levels of flywheel speed and axial pressure.

Cola, M.J.; Baeslack, W.A. III; Kou, M.

1994-12-31T23:59:59.000Z

267

Achievement Rewards for College Scientists ARCS Foundation, Inc.  

E-Print Network [OSTI]

Achievement Rewards for College Scientists ARCS Foundation, Inc. For more information on how of the ARCS Foundation, Inc. funds seven scholarships for exceptional University of Georgia doctoral students. Available to attend the ARCS Foundation Awards Luncheon in Atlanta on November 21, 2013. ARCS Foundation

Arnold, Jonathan

268

Continuous nanoparticle generation and assembly by atmospheric pressure arc discharge  

E-Print Network [OSTI]

Continuous nanoparticle generation and assembly by atmospheric pressure arc discharge Jesse J. Cole a dc arc discharge plasma. The particles are positively charged by the arc and form a room temperature precursor materials.5,6 High temperature plasmas in the form of dc arc discharges led to the discovery

Jacobs, Heiko O.

269

Diffusion-Welded Microchannel Heat Exchanger for Industrial Processes  

SciTech Connect (OSTI)

The goal of next generation reactors is to increase energy ef?ciency in the production of electricity and provide high-temperature heat for industrial processes. The ef?cient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process. The need for ef?ciency, compactness, and safety challenge the boundaries of existing heat exchanger technology. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more ef?cient industrial processes. Modern compact heat exchangers can provide high compactness, a measure of the ratio of surface area-to-volume of a heat exchange. The microchannel heat exchanger studied here is a plate-type, robust heat exchanger that combines compactness, low pressure drop, high effectiveness, and the ability to operate with a very large pressure differential between hot and cold sides. The plates are etched and thereafter joined by diffusion welding, resulting in extremely strong all-metal heat exchanger cores. After bonding, any number of core blocks can be welded together to provide the required ?ow capacity. This study explores the microchannel heat exchanger and draws conclusions about diffusion welding/bonding for joining heat exchanger plates, with both experimental and computational modeling, along with existing challenges and gaps. Also, presented is a thermal design method for determining overall design speci?cations for a microchannel printed circuit heat exchanger for both supercritical (24 MPa) and subcritical (17 MPa) Rankine power cycles.

Piyush Sabharwall; Denis E. Clark; Michael V. Glazoff; Michael G. McKellar; Ronald E. Mizia

2013-03-01T23:59:59.000Z

270

AdaptiveARC | Open Energy Information  

Open Energy Info (EERE)

AdaptiveARC AdaptiveARC Jump to: navigation, search Name AdaptiveARC Address 7683 Sitio Manana Place Carlsbad, California Zip 92009 Sector Biomass Product Waste-to-clean-energy startup is developing an arc-plasma reactor Website http://www.adaptivearc.com/ Coordinates 33.07959°, -117.22539° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.07959,"lon":-117.22539,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

271

Arc Statistics in Clusters: Galaxy Contribution  

E-Print Network [OSTI]

The frequency with which background galaxies appear as long arcs as a result of gravitational lensing by foreground clusters of galaxies has recently been found to be a very sensitive probe of cosmological models by Bartelmann et al. (1998). They have found that such arcs would be expected far less frequently than observed (by an order of magnitude) in the currently favored model for the universe, with a large cosmological constant $\\Omega_\\Lambda \\sim 0.7$. Here we analyze whether including the effect of cluster galaxies on the likelihood of clusters to generate long-arc images of background galaxies can change the statistics. Taking into account a variety of constraints on the properties of cluster galaxies, we find that there are not enough sufficiently massive galaxies in a cluster for them to significantly enhance the cross section of clusters to generate long arcs. We find that cluster galaxies typically enhance the cross section by only $\\lesssim 15%$.

R. A. Flores; A. H. Maller; J. R. Primack

1999-09-23T23:59:59.000Z

272

Detection of arcs in automotive electrical systems  

E-Print Network [OSTI]

At the present time, there is no established method for the detection of DC electric arcing. This is a concern for forthcoming advanced automotive electrical systems which consist of higher DC electric power bus voltages, ...

Mishrikey, Matthew David

2005-01-01T23:59:59.000Z

273

Pulsed Magnetic Welding for Advanced Core and Cladding Steel  

SciTech Connect (OSTI)

To investigate a solid-state joining method, pulsed magnetic welding (PMW), for welding the advanced core and cladding steels to be used in Generation IV systems, with a specific application for fuel pin end-plug welding. As another alternative solid state welding technique, pulsed magnetic welding (PMW) has not been extensively explored on the advanced steels. The resultant weld can be free from microstructure defects (pores, non-matallic inclusions, segregation of alloying elements). More specifically, the following objectives are to be achieved, 1) To design a suitable welding apparatus fixture, and optimize welding parameters for repeatable and acceptable joining of the fuel pin end-plug. The welding will be evaluated using tensile tests for lap joint weldments and helium leak tests for the fuel pin end-plug. 2) investigate the microstructural and mechanical properties changes in PMW weldments of proposed advanced core and cladding alloys. 3) Simulate the irradiation effects on the PWM weldments using ion irradiation.

Cao, Guoping; Yang, Yong

2013-12-19T23:59:59.000Z

274

Method and apparatus for real time weld monitoring  

DOE Patents [OSTI]

An improved method and apparatus are provided for real time weld monitoring. An infrared signature emitted by a hot weld surface during welding is detected and this signature is compared with an infrared signature emitted by the weld surface during steady state conditions. The result is correlated with weld penetration. The signal processing is simpler than for either UV or acoustic techniques. Changes in the weld process, such as changes in the transmitted laser beam power, quality or positioning of the laser beam, change the resulting weld surface features and temperature of the weld surface, thereby resulting in a change in the direction and amount of infrared emissions. This change in emissions is monitored by an IR sensitive detecting apparatus that is sensitive to the appropriate wavelength region for the hot weld surface.

Leong, Keng H. (Lemont, IL); Hunter, Boyd V. (Bolingbrook, IL)

1997-01-01T23:59:59.000Z

275

Current Issues and Problems in Welding Science  

Science Journals Connector (OSTI)

...and properties. Rapid heating, cooling...thermomechanical simulation, and welding of...recent advances in rapid so-lidification...prevalent during rapid solidification...microstruc-tural modeling within the HAZ and...progressively replaced by automated systems to achieve...

S. A. David; T. DebRoy

1992-07-24T23:59:59.000Z

276

Vibration welding system with thin film sensor  

DOE Patents [OSTI]

A vibration welding system includes an anvil, a welding horn, a thin film sensor, and a process controller. The anvil and horn include working surfaces that contact a work piece during the welding process. The sensor measures a control value at the working surface. The measured control value is transmitted to the controller, which controls the system in part using the measured control value. The thin film sensor may include a plurality of thermopiles and thermocouples which collectively measure temperature and heat flux at the working surface. A method includes providing a welder device with a slot adjacent to a working surface of the welder device, inserting the thin film sensor into the slot, and using the sensor to measure a control value at the working surface. A process controller then controls the vibration welding system in part using the measured control value.

Cai, Wayne W; Abell, Jeffrey A; Li, Xiaochun; Choi, Hongseok; Zhao, Jingzhou

2014-03-18T23:59:59.000Z

277

Wet welding qualification trials at 35 MSW  

SciTech Connect (OSTI)

Wet welding is gaining increased attention and attraction for application on marine buildings and offshore structures all over the world because of its versatility, flexibility and mobility in combination with low investment costs. In a common research and development project between PETROBRAS/CENPES, Rio de Janeiro, Brazil and GKSS Research Centre, Geesthacht, Germany wet welding qualification trials have been performed in different water depths up to 35 msw. The tests have been performed with newly developed electrodes in two different wet welding procedures. The experiments have been carried out on SS- as well as on 5F-specimens acc. ANSI/AWS D 3.6-89. Results will be presented in respect to the performance of the two welding procedures especially with regard to the avoidance of hydrogen induced cold cracking and high hardness values.

Dos Santos, V.R.; Teixeira, C.J. [Petrobras/CENPES, Rio de Janeiro (Brazil); Szelagowski, P.J.F. [GKSS Research Center, Geesthacht (Germany)

1993-12-31T23:59:59.000Z

278

The 'world's largest' Inconel waterwall weld overlay  

SciTech Connect (OSTI)

An 11,000 square foot Inconel 655 weld repaired severe wastage caused by low NOx firing with coal/petcoke at the Belledune generating station in New Brunswick, Canada. 1 ref., 1 fig., 3 photos.

MacLean, K.; Fournier, E.; Gomez-Grande, J.; Scandroli, T. [New Brunswick Power Generation (United States)

2009-11-15T23:59:59.000Z

279

Ion source with improved primary arc collimation  

DOE Patents [OSTI]

An improved negative ion source is provided in which a self-biasing, molybdenum collimator is used to define the primary electron stream arc discharge from a filament operated at a negative potential. The collimator is located between the anode and the filament. It is electrically connected to the anode by means of an appropriate size resistor such that the collimator is biased at essentially the filament voltage during operation. Initially, the full arc voltage appears across the filament to collimator until the arc discharge strikes. Then the collimator biases itself to essentially filament potential due to current flow through the resistor thus defining the primary electron stream without intercepting any appreciable arc power. The collimator aperture is slightly smaller than the anode aperture to shield the anode from the arc power, thereby preventing the exposure of the anode to the full arc power which, in the past, has caused overheating and erosion of the anode collimator during extended time pulsed-beam operation of the source. With the self-biasing collimator of this invention, the ion source may be operated from short pulse periods to steady-state without destroying the anode.

Dagenhart, William K. (Oak Ridge, TN)

1985-01-01T23:59:59.000Z

280

Laser welding dissimilar reflective alloys  

SciTech Connect (OSTI)

This project, jointly sponsored by Rocketdyne and CSTAR, involves the development of laser joining of materials which have heretofore been impractical to bond. Of particular interest are joints between stainless steel and copper and also aluminum 6061 to aluminum 2219. CSTAR has a unique opportunity in this area since both the process and development and diagnostics are of interest to industry. Initial results using the pulse tailored laser welding technique developed in CLA for joining crack sensitive materials have proven promising for the aluminum joints based upon metallurgical and electronic microprobe analysis. A declaration of success requires additional mechanical testing. A CW technique has been applied to the stainless-copper joining with some preliminary success. These joints are of significant interest for aeronautics and rocket propulsion applications and the project is expected to continue.

Mccay, M.H.; Gopinathan, S.; Kahlen, F.; Speigel, L.

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

The application of the fusion method of thermit welding to small diameter tubing: An analysis of joint geometry.  

E-Print Network [OSTI]

by working (g:zs3). Thermit weld metal can be regarded as having physical properties closely approaching those of forged steel (l3:2S3). In summary, the thermit process. . . . . . has been used in almost every industry (I:17-2D). Llhile the plastic... (February 19, 1970). 3. Davies, A. C. , The Science and Practice of Lleldin Cambridge University Press 1941 4. Deppeler, 3. H. , "Thermit Welding and the Steel Mill, " 3ournal of the American Weldin Societ 10, (May 1931 5. Deppeler, 3. H. , "Thermit...

Glynn, Thomas Michael

2012-06-07T23:59:59.000Z

282

Design consideration for wet welded joints  

SciTech Connect (OSTI)

Wet welding has become a joining technique that under certain circumstances can provide results which cannot be distinguished between wet or dry production and the achievable mechanical quality is comparable to dry atmospheric welds. Wet welding is not a process which can be applied easily and which can be properly handled by untrained diver welders. Wet welding is more than any other kind of welding process or procedure a joining technique that requires the full job-concentration and -knowledge of an excellent trained and skilled diver welder throughout the whole production time, who is 100% identifying himself with his task. Furthermore he must be fully aware of the production requirements and possible metallurgical/environmental reactions and outcomes. He must be able to be fully concentrated on the process performance throughout his total work shift. In short: he must be an outstanding expert in his field. The following paper will highlight these subjects and show the necessity of their exact observation to achieve excellent quality in wet welding.

Szelagowski, P.; Osthus, V. [GKSS Research Center, Geesthacht (Germany); Petershagen, H.; Pohl, R. [Univ. Hamburg (Germany). Inst. fuer Schiffbau; Lafaye, G. [Stolt Comex Seaway S.A., Marseille (France)

1996-12-01T23:59:59.000Z

283

Advanced tests of wet welded joints  

SciTech Connect (OSTI)

Wet Welding has in former times only been applied to secondary structural components. Nowadays wet welding has become an upcoming repair process due to high process flexibility, its low investment costs and its high versatility. Even the quality of the wet welded joints has been improved remarkably due to intensive and concentrated development activities. However, especially in the North Sea regions owners of offshore structures and classifying authorities still hesitate to recognize the process as a reliable alternative to dry hyperbaric welding repair methods. It therefore requires further activities especially in the field of data development for life prediction of such repaired components. Advanced testing methods are necessary, additional design criteria are to be developed and achievable weldment quality data are to be included in acknowledged and approved standards and recommendations to improve the credibility of the process and to solve the problem of quality assurance for wet welded joints. A comprehensive project, sponsored by the European Community under the Thermie Programme, is in progress to develop new testing procedures to generate the required data and design criteria for the future application of the wet welding process to main components of offshore structures. It is the aim of the project to establish additional fitness for purpose data for this process.

Pachniuk, I. [Stolt Comex Seaway S.A., Marseille (France); Petershagen, H.; Pohl, R. [Univ. Hamburg (Germany); Szelagowski, P.; Drews, O. [GKSS Research Centre, Geesthacht (Germany)

1994-12-31T23:59:59.000Z

284

Effects of xenon cover gas in CO/sub 2/ laser welding  

SciTech Connect (OSTI)

Weld spatter in CO/sub 2/ laser welding is detrimental to miniature components. The effects of using xenon gas as an inert laser welding atmosphere to reduce weld spatter are discussed. The laser plume characteristics, weld penetration, and weld spatter are evaluated.

Hendrix, T.L.

1980-07-01T23:59:59.000Z

285

The Consumption of Carbon in the Electric Arc. I. Variation with Current and Arc-Length. II. Influence upon the Luminous Radiation from the Arc  

Science Journals Connector (OSTI)

1 December 1915 research-article The Consumption of Carbon in the Electric Arc. I. Variation with Current and Arc-Length. II. Influence upon the Luminous Radiation from the...

1915-01-01T23:59:59.000Z

286

Apparatus for maintaining aligment of a shrinking weld joint in an electron-beam welding operation  

DOE Patents [OSTI]

The invention is directed to an apparatus for automatically maintaining a shrinking weld joint in alignement with an electron beam during an electron-beam multipass-welding operation. The apparatus utilizes a bias means for continually urging a workpiece-supporting face plate away from a carriage mounted base that rotatably supports the face plate. The extent of displacement of the face plate away from the base in indicative of the shrinkage occuring in the weld joint area. This displacement is measured and is used to move the base on the carriage a distance equal to one-half the displacement for aligning the weld joint with the electron beam during each welding pass.

Trent, J.B.; Murphy, J.L.

1980-01-03T23:59:59.000Z

287

Design study for wire and arc additive manufacture  

Science Journals Connector (OSTI)

Additive Manufacture (AM) is a technique whereby freeform structures are produced by building up material in a layer by layer fashion. Among the different AM processes, Wire and Arc Additive Manufacture (WAAM) has the ability to manufacture large custom-made metal workpiece with high efficiency. A design study has been performed to explore the process capabilities of fabricating complicated geometries using WAAM. Features such as enclosed structures, crossing structures, and balanced building structures have been investigated in this study. Finite Element (FE) models are employed to take the thermo-mechanical performance into account. Robot tool path design has been performed to transfer the WAAM component designs into real components efficiently. This paper covers these essential design steps from a technical as well as practical point of view.

Jörn Mehnen; Jialuo Ding; Helen Lockett; Panos Kazanas

2014-01-01T23:59:59.000Z

288

ISSN 1061-3862, International Journal of Self-Propagating High-Temperature Synthesis, 2007, Vol. 16, No. 3, pp. 154168. Allerton Press, Inc., 2007. 1. INTRODUCTION  

E-Print Network [OSTI]

[1]. Another relevant technique is exothermically assisted shielded metal arc welding, where: (i) dissimilar materials such as ceramics and metals and (ii) refractory materials, such as graphite heterogeneous reac- tive systems falls under the American Welding Soci- ety's exothermic welding classification

Mukasyan, Alexander

289

Training Program EHS ~ 244: Resistance Spot Welding Safety Training  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

4: Resistance Spot Welding Safety Training 4: Resistance Spot Welding Safety Training Course Syllabus Subject Category: Resistance Spot Welding Course Prerequisite: None Course Length: 25 minutes Medical Approval: No Delivery Mode: Web-Based Course Goal: Participants will be introduced to resistance spot welding processes, hazards, and safe work practices. Course Objectives: By the end of this course, you will be able to: * Identify resistance spot welding processes * Identify hazards, safe work practices, and personal protective equipment associated with resistance spot welding * Recognize the purpose of resistance spot welding schedules * Locate resistance spot welding schedule Subject Matter Expert: Joe Dionne x 7586 Training Compliance: 29 CFR 1910 Subparts O & Z, 29 CFR 1926 Subparts J & Z

290

FINITE ELEMENT ANALYSIS OF STEEL WELDED COVERPLATE INCLUDING COMPOSITE DOUBLERS  

E-Print Network [OSTI]

With the increasing focus on welded bridge members resulting in crack initiation and propagation, there is a large demand for creative solutions. One of these solutions includes the application of composite doublers over the critical weld. In order...

Petri, Brad

2008-05-15T23:59:59.000Z

291

On-Line Weld NDE with IR Thermography  

Broader source: Energy.gov (indexed) [DOE]

with gaps 17 Managed by UT-Battelle for the Department of Energy no weld Destructive measurement Post-weld signature Accomplishment: Actual Auto Body Parts 2T auto body structures...

292

Effect of cerium ions in an arc peripheral plasma on the growth of radial single-walled carbon nanotubes  

SciTech Connect (OSTI)

Radial single-walled carbon nanotubes (radial SWCNTs) are formed by using a direct current (dc) arc discharge when carbon and metal atoms are mixed in a gas phase after the vaporization and cooled together in a liquid droplet. Since SWCNTs sprout through the precipitation of saturated carbon atoms from liquid droplets during cooling, a mass synthesis of radial SWCNTs can be achieved when a large number of liquid droplets are generated. In order to understand the effects of arc peripheral plasma parameters (electrons, ions, radical atoms, and molecules) on the growth of radial SWCNTs, the optimum production efficiency of radial SWCNTs is investigated by superimposing a radio-frequency (rf) plasma on the thermal arc plasma and controlling the arc peripheral plasma density. Two parameters--the rf power and the dc potential--of the rf electrode, which is equipped above 20 mm from the center of an arc-discharge point, are changed with the constant He pressure (200 Torr), dc arc current (75 A), and power (2000 W). The production yield of radial SWCNTs is found to be enhanced under the condition of the rf power of 100 W and the dc component of the rf electrode voltage of -22 V, revealing that the optimum ion flux and ion bombardment energy are important key parameters for the formation of radial SWCNTs.

Sato, Y.; Motomiya, K.; Jeyadevan, B.; Tohji, K.; Sato, G.; Ishida, H.; Hirata, T.; Hatakeyama, R. [Graduate School of Environmental Studies, Tohoku University, Sendai 980-8579 (Japan); Department of Electronic Engineering, Tohoku University, Sendai 980-8579 (Japan)

2005-11-01T23:59:59.000Z

293

Vertical Arc for ILC Low Emittance Transport  

SciTech Connect (OSTI)

The design and parameters of a vertical arc for the ILC Low Emittance Transport (LET) are reviewed. A 1 TeV CM ILC which relies upon 30 MV/m accelerating cavities with a packing fraction of 65% will require almost 48 km of main linac, which suggests that the total site length including BDS and bunch compressors will be on the order of 53 km. If built in a laser-straight tunnel with the low-energy ends near the surface, and assuming a perfectly spherical ''cue ball'' planetary surface with radius 6370 km, the collider halls will necessarily be 55 meters below grade, as shown in the top plot of Figure 1. Such depths would demand extensive use of deep tunneling, which would potentially drive up the cost and difficulty of ILC construction. An alternate solution is to use discrete vertical arcs at a few locations to allow a ''piecewise straight'' construction in which the depth of the tunnel below grade does not vary by more than a few meters. This approach is shown schematically in the bottom plot of Figure 1. In this Note we consider the issues for a design with one such vertical arc at the 250 GeV/c point (ie, midway down the linac for 1 TeV CM), and a second arc at the entrance to the BDS (ie, the entire BDS lies in one plane, with vertical arcs at each end).

Tenenbaum, P.; Woodley, M.; /SLAC

2005-06-07T23:59:59.000Z

294

Ion source with improved primary arc collimation  

DOE Patents [OSTI]

An improved negative ion source is provided in which a self-biasing, molybdenum collimator is used to define the primary electron stream arc discharge from a filament operated at a negative potential. The collimator is located between the anode and the filament. It is electrically connected to the anode by means of an appropriate size resistor such that the collimator is biased at essentially the filament voltage during operation. Initially, the full arc voltage appears across the filament to collimator until the arc discharge strikes. Then the collimator biases itself to essentially filament potential due to current flow through the resistor thus defining the primary electron stream without intercepting any appreciable arc power. The collimator aperture is slightly smaller than the anode aperture to shield the anode from the arc power which, in the past, has caused overheating and erosion of the anode collimator during extended time pulsed-beam operation of the source. With the self-biasing collimator of this invention, the ion source may be operated from short pulse periods to steady-state without destroying the anode.

Dagenhart, W.K.

1983-12-16T23:59:59.000Z

295

A 2D finite element with through the thickness parabolic temperature distribution for heat transfer simulations including welding  

Science Journals Connector (OSTI)

Abstract The arc welding process involves thermal cycles that cause the appearance of undesirable residual stresses. The determination of this thermal cycle is the first step to a thermomechanical analysis that allows the numerical calculation of residual stresses. This study describes the formulation of a 2D finite element with through the thickness parabolic temperature distribution, including an element estabilization procedure. The 2D element described in this paper can be used to perform thermal analysis more economically than 3D elements, especially in plates, because the number of degrees of freedom through the thickness will always be three. A numerical model of a tungsten arc welding (GTAW) setup was made based on published experimental results. Size and distribution of the heat source input, thermal properties dependent on temperature, surface heat losses by convection and latent heat during phase change were considered. In parallel the same setup was modeled using ANSYS software with 3D elements (SOLID70) to compare against 2D numerical results. The results obtained by 2D model, 3D model and experimental data showed good agreement.

Darlesson Alves do Carmo; Alfredo Rocha de Faria

2015-01-01T23:59:59.000Z

296

Effect of Post-Weld Heat Treatment on Creep Rupture Properties of Grade 91 Steel Heavy Section Welds  

SciTech Connect (OSTI)

This project will conduct a systematic metallurgical study on the effect of post-weld heat treatment (PWHT) on the creep rupture properties of P91 heavy section welds. The objective is to develop a technical guide for selecting PWHT parameters, and to predict expected creep-rupture life based on the selection of heat treatment parameters. The project consists of four interdependent tasks: Experimentally and numerically characterize the temperature fields of typical post-weld heat treatment procedures for various weld and joint configurations to be used in Gen IV systems. Characterize the microstructure of various regions, including the weld fusion zone, coarse-grain heat-affected zone, and fine-grain heat affected zone, in the welds that underwent the various welding and PWHT thermal histories. Conduct creep and creep-rupture testing of coupons extracted from actual and physically simulated welds. Establish the relationship among PWHT parameters, thermal histories, microstructure, creep, and creep-rupture properties.

Leijun Li

2012-11-02T23:59:59.000Z

297

Apparatus for the concurrent inspection of partially completed welds  

DOE Patents [OSTI]

An apparatus for the concurrent inspection of partially completed welds is described in which is utilized in combination with a moveable welder for forming a partially completed weld, and an ultrasonic generator mounted on a moveable welder in which is reciprocally moveable along a path of travel which is laterally disposed relative to the partially completed weld.

Smartt, Herschel B. (Idaho Falls, ID); Johnson, John A. (Idaho Falls, ID); Larsen, Eric D. (Idaho Falls, ID); Bitsoi, Rodney J. (Ririe, ID); Perrenoud, Ben C. (Rigby, ID); Miller, Karen S. (Idaho Falls, ID); Pace, David P. (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

298

Local mechanical properties of Alloy 82/182 dissimilar weld joint between SA508 Gr.1a and F316 SS at RT and 320C  

SciTech Connect (OSTI)

This paper presents the variations of local mechanical and microstructural properties in dissimilar metal weld joints consisting of the SA508 Gr.1a ferritic steel, Alloy 82/182 filler metal, and F316 austenitic stainless steel. Flat or round tensile specimens and transmission electron microscopy disks were taken from the base metals, welds, and heat-affected zones (HAZ) of the joints and tested at room temperature (RT) and/or at 320 C. The tensile test results indicated that the mechanical property was relatively uniform within each material zone, but varied considerably between different zones. Further, significant variations were observed both in the austenitic HAZ of F316 SS and in the ferritic HAZ of SA508 Gr.1a. The yield stress (YS) of the weld metal was under-matched with respect to the HAZs of SA508 Gr.1a and F316 SS by 0.78 to 0.92, although the YS was over-matched with respect to both base metals. The minimum ductility occurred in the HAZ of SA508 Gr.1 at both test temperatures. The plastic instability stress also varied considerably in the weld joints, with minimum values occurring in the SA508 Gr.1a base metal at RT and in the HAZ of F316 SS at 320 C, suggesting that the probability of ductile failure caused by a unstable deformation at the Alloy 82/182 buttering layer is low. Within the HAZ of SA508 Gr.1a, the gradient of the YS and ultimate tensile strength (UTS) was significant, primarily because of the different microstructures produced by the phase transformation during the welding process. The increment of YS was unexpectedly high in the HAZ of F316 SS, which was explained by the strain hardening induced by a strain mismatch between the weldment and the base metal. This was confirmed by the transmission electron micrographs showing high dislocation density in the HAZ.

Byun, Thak Sang [ORNL; Kim, Jin Weon [ORNL

2009-01-01T23:59:59.000Z

299

Microstructural development in PWA-1480 electron beam welds: An atom probe field ion microscopy study  

SciTech Connect (OSTI)

The microstructure development in PWA-1480 superalloy electron beam weld (Ni-11.0 at. % Al-11.5% Cr-1.9% Ti-5.1% Co-4.0% Ta-1.3% W) was characterized. Optical microscopy revealed a branched dendritic structure in the weld metal. Transmission electron microscopy of these welds, in the as-welded condition, showed fine cuboidal (0.05--0.5 {mu}m) L1{sub 2}-ordered {gamma}{prime} precipitates within the y grains. The average volume percentage of {gamma}{prime} precipitates was found to be {approx}5%. Atom probe analyses revealed that the composition of {gamma} matrix was Ni-4.6 at. % Al-25.5% Cr-0.4% Ti-9.4% Co-0.8% Ta-2.9% W and that of {gamma}{prime} precipitates was Ni-17.3 at. % Al-2.6% Cr-2.4% Ti-3.0% Co-7.4% Ta-1.3% W. These compositions were compared with the previous APFIM analyses of commercial PWA-1480 single crystals that had received conventional heat treatments. Small differences were found in the chromium and aluminum levels and these may be due to the nonequilibrium nature of phase transformations that occur during weld cooling. No solute segregation was detected at the {gamma}-{gamma}{prime}interface. The APFIM results were also compared with the thermodynamic calculations of alloying element partitioning between {gamma} and {gamma}{prime} using the ThermoCalc{trademark} software.

David, S.A.; Miller, M.K. [Oak Ridge National Lab., TN (United States); Babu, S.S. [The Pennsylvania State Univ., State College, PA (United States)

1995-12-31T23:59:59.000Z

300

Ion source based on the cathodic arc  

DOE Patents [OSTI]

A cylindrically symmetric arc source to produce a ring of ions which leave the surface of the arc target radially and are reflected by electrostatic fields present in the source to a point of use, such as a part to be coated, is described. An array of electrically isolated rings positioned in the source serves the dual purpose of minimizing bouncing of macroparticles and providing electrical insulation to maximize the electric field gradients within the source. The source also includes a series of baffles which function as a filtering or trapping mechanism for any macroparticles. 3 figures.

Sanders, D.M.; Falabella, S.

1994-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Ion source based on the cathodic arc  

DOE Patents [OSTI]

A cylindrically symmetric arc source to produce a ring of ions which leave the surface of the arc target radially and are reflected by electrostatic fields present in the source to a point of use, such as a part to be coated. An array of electrically isolated rings positioned in the source serves the dual purpose of minimizing bouncing of macroparticles and providing electrical insulation to maximize the electric field gradients within the source. The source also includes a series of baffles which function as a filtering or trapping mechanism for any macroparticles.

Sanders, David M. (Livermore, CA); Falabella, Steven (Livermore, CA)

1994-01-01T23:59:59.000Z

302

CONTROL OF AN ARC DISCHARGE BY MEANS OF A GRID  

Science Journals Connector (OSTI)

CONTROL OF AN ARC DISCHARGE BY MEANS OF A GRID Albert...Research Laboratory, General Electric Co., Schenectady , N. Y. CONTROL OF AN ARC DISCHARGE BY MEANS OF A GRID. | Research Laboratory, General Electric Co., Schenectady , N...

Albert W. Hull; Irving Langmuir

1929-01-01T23:59:59.000Z

303

Fluorination of Arc-Produced Carbon Material Containing Multiwall Nanotubes  

Science Journals Connector (OSTI)

In this work we studied the fluorination process of MWNTs produced in an electric arc. ... Carbon material was synthesized by using a setup for arc-discharge graphite evaporation described elsewhere. ...

Nicolai F. Yudanov; Alexander V. Okotrub; Yuri V. Shubin; Lyudmila I. Yudanova; Lyubov G. Bulusheva; Andrew L. Chuvilin; Jean-Marc Bonard

2002-03-21T23:59:59.000Z

304

Type B Accident Investigation of the Savannah River Site Arc...  

Broader source: Energy.gov (indexed) [DOE]

the Savannah River Site Arc Flash Burn Injury on September 23, 2009, in the D Area Powerhouse Type B Accident Investigation of the Savannah River Site Arc Flash Burn Injury on...

305

Measurement of the temperature of a pulsating electric arc discharge  

Science Journals Connector (OSTI)

A simple method for determining the temperature on the axis of an oscillating arc column is proposed.

A. Marotta

1994-06-01T23:59:59.000Z

306

Method and apparatus for welding precipitation hardenable materials  

DOE Patents [OSTI]

A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined. 5 figures.

Murray, H. Jr.; Harris, I.D.; Ratka, J.O.; Spiegelberg, W.D.

1994-06-28T23:59:59.000Z

307

Method and apparatus for welding precipitation hardenable materials  

DOE Patents [OSTI]

A method for welding together members consisting of precipitation age hardened materials includes the steps of selecting a weld filler material that has substantially the same composition as the materials being joined, and an age hardening characteristic temperature age threshold below that of the aging kinetic temperature range of the materials being joined, whereby after welding the members together, the resulting weld and heat affected zone (HAZ) are heat treated at a temperature below that of the kinetic temperature range of the materials joined, for obtaining substantially the same mechanical characteristics for the weld and HAZ, as for the parent material of the members joined.

Murray, Jr., Holt (Hopewell, NJ); Harris, Ian D. (Dublin, OH); Ratka, John O. (Cleveland Heights, OH); Spiegelberg, William D. (Parma, OH)

1994-01-01T23:59:59.000Z

308

Achievement Rewards for College Scientists ARCS Foundation, Inc.  

E-Print Network [OSTI]

Achievement Rewards for College Scientists ARCS Foundation, Inc. Biomedical and Health Sciences the Atlanta chapter of the ARCS Foundation, Inc. funds eight scholarships for exceptional University.S. citizenship. · GPA of 3.5 or above. · Available to attend the ARCS Foundation Awards Luncheon in Atlanta

Arnold, Jonathan

309

Decomposition of Naphthalene by dc Gliding Arc Gas Discharge  

Science Journals Connector (OSTI)

Decomposition of Naphthalene by dc Gliding Arc Gas Discharge ... In the air and oxygen gliding arc discharges, the naphthalene degradation is mainly governed by reactions with oxygen-derived radicals. ... Therefore, the local electric field strength is relatively low in argon gliding arc plasma. ...

Liang Yu; Xiaodong Li; Xin Tu; Yu Wang; Shengyong Lu; Jianhua Yan

2009-12-11T23:59:59.000Z

310

Way to reduce arc voltage losses in hybrid thermionic converters  

SciTech Connect (OSTI)

Experimental results are reported concerning the output and emission characteristics of the arc and hybrid regimes in a plane-parallel thermionic converter with Pt--Zr--O electrode pair. It is shown that arc voltage losses can be reduced to values below those obtainable in ordinary arc thermionic converters.

Tskhakaya, V.K.; Yarygin, V.I.

1982-03-01T23:59:59.000Z

311

Calculating the parameters of electric-arc heaters with gas-stabilized arcs  

Science Journals Connector (OSTI)

We used a turbulent model of a longitudinally streamlined electric arc to derive an analytical solution for the ... of the distribution of the primary flow and discharge parameters in a cylindrical discharge chan...

N. A. Zyrichev

1969-07-01T23:59:59.000Z

312

Fluor Hanford Nuclear Material Stabilization Project Welding Manual  

SciTech Connect (OSTI)

The purpose of this section of the welding manual is to: (1) Provide a general description of the major responsibilities of the organizations involved with welding. (2) Provide general guidance concerning the application of codes related to welding. This manual contains requirements for welding for all Fluor Hanford (FH) welding operators working on the W460 Project, in the Plutonium Finishing Plant (PFP) at the U. S. Department of Energy (DOE) Hanford facilities. These procedures and any additional requirements for these joining processes can be used by all FH welding operators that are qualified. The Welding Procedure Specifications (WPS) found in this document were established from Procedure Qualification Records (PQR) qualified by FH specifically for the W460 Project. PQRs are permanent records of the initial testing and qualification program and are used to backup, and support, the WPS. The identification numbers of the supporting PQR(s) are recorded on each WPS. All PQRs are permanently stored under the supervision of the Fluor Hanford Welding Engineer (FHWE). New PQRs and WPSs will continue to be developed as necessary. The qualification of welders, welding operators and welding procedures will be performed for FH under supervision and concurrent of the FHWE. All new welding procedures to be entered in this manual or welder personnel to be added to the welder qualification database, shall be approved by the FHWE.

BERKEY, J.R.

2000-10-20T23:59:59.000Z

313

Method for the concurrent ultrasonic inspection of partially completed welds  

DOE Patents [OSTI]

A method for the concurrent ultrasonic inspection of partially completed welds is disclosed and which includes providing a pair of transducers which are individually positioned on the opposite sides of a partially completed weld to be inspected; moving the transducers along the length of and laterally inwardly and outwardly relative to the partially completed weld; pulsing the respective transducers to produce an ultrasonic signal which passes through or is reflected from the partially completed weld; receiving from the respective transducers ultrasonic signals which pass through or are reflected from the partially completed welds; and analyzing the ultrasonic signal which has passed through or is reflected from the partially completed weld to determine the presence of any weld defects.

Johnson, John A. (Idaho Falls, ID); Larsen, Eric D. (Idaho Falls, ID); Miller, Karen S. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); McJunkin, Timothy R. (Idaho Falls, ID)

2002-01-01T23:59:59.000Z

314

Page 1 of 2 -ARC Cost Transfer Guide v. 06/14/13 ARC SPONSORED PROJECT COST TRANSFER GUIDE  

E-Print Network [OSTI]

Page 1 of 2 - ARC Cost Transfer Guide v. 06/14/13 ARC SPONSORED PROJECT COST TRANSFER GUIDE There are three ways to move expenditures onto, off of, or between Sponsored Projects in ARC: AP Journal Voucher in which the voucher accounting date falls, and they are being moved to or between Sponsored Projects GL

Hone, James

315

A review comparing cathodic arcs and high power impulse magnetron sputtering (HiPIMS)  

SciTech Connect (OSTI)

High power impulse magnetron sputtering (HiPIMS) has been in the center of attention over the last years as it is an emerging physical vapor deposition (PVD) technology that combines advantages of magnetron sputtering with various forms of energetic deposition of films such as ion plating and cathodic arc plasma deposition. It should not come at a surprise that many extension and variations of HiPIMS make use, intentionally or unintentionally, of previously discovered approaches to film processing such as substrate surface preparation by metal ion sputtering and phased biasing for film texture and stress control. Therefore, in this review, an overview is given on some historical developments and features of cathodic arc and HiPIMS plasmas, showing commonalities and differences. To limit the scope, emphasis is put on plasma properties, as opposed to surveying the vast literature on specific film materials and their properties.

Anders, Andre

2014-08-17T23:59:59.000Z

316

Exploring high temperature phenomena related to post-detonation using an electric arc  

SciTech Connect (OSTI)

We report a study of materials recovered from a uranium-containing plasma generated by an electric arc. The device used to generate the arc is capable of sustaining temperatures of an eV or higher for up to 100??s. Samples took the form of a 4??m-thick film deposited onto 8 pairs of 17??m-thick Cu electrodes supported on a 25??m-thick Kapton backing and sandwiched between glass plates. Materials recovered from the glass plates and around the electrode tips after passage of an arc were characterized using scanning and transmission electron microscopy. Recovered materials included a variety of crystalline compounds (e.g., UO{sub 2}, UC{sub 2}, UCu{sub 5},) as well as mixtures of uranium and amorphous glass. Most of the materials collected on the glass plates took the form of spherules having a wide range of diameters from tens of nanometers to tens of micrometers. The composition and size of the spherules depended on location, indicating different chemical and physical environments. A theoretical analysis we have carried out suggests that the submicron spherules presumably formed by deposition during the arc discharge, while at the same time the glass plates were strongly heated due to absorption of plasma radiation mainly by islands of deposited metals (Cu, U). The surface temperature of the glass plates is expected to have risen to ?2300?K thus producing a liquefied glass layer, likely diffusions of the deposited metals on the hot glass surface and into this layer were accompanied by chemical reactions that gave rise to the observed materials. These results, together with the compact scale and relatively low cost, suggest that the experimental technique provides a practical approach to investigate the complex physical and chemical processes that occur when actinide-containing material interacts with the environment at high temperature, for example, during fallout formation following a nuclear detonation.

Dai, Z. R., E-mail: dai1@llnl.gov; Crowhurst, J. C.; Grant, C. D.; Knight, K. B.; Tang, V.; Chernov, A. A.; Cook, E. G.; Lotscher, J. P.; Hutcheon, I. D. [Lawrence Livermore National Laboratory, Livermore, California 94551-0808 (United States)

2013-11-28T23:59:59.000Z

317

Hybrid Arc Cell Studies: Status Report  

SciTech Connect (OSTI)

I report on the status, at the end of FY12, of the studies of an arc cell for a hybrid synchrotron accelerating from 375 GeV/c to 750 GeV/c in momentum. Garren produced a complete lattice that gives a good outline of the structure of a hybrid synchrotron lattice. It is, however, lacking in some details: it does not maintain a constant time of flight, it lacks chromaticity correction, its cell structure is not ideal for removing aberrations from chromaticity correction, and it probably needs more space between magnets. I have begun studying cell structures for the arc cells to optimize the lattice performance and cost. I present some preliminary results for two magnets per half cell. I then discuss difficulties encountered, some preliminary attempts at resolving them, and the future plans for this work.

Berg J. S.

2012-09-28T23:59:59.000Z

318

Cathodic Vacuum Arc Plasma of Thallium  

SciTech Connect (OSTI)

Thallium arc plasma was investigated in a vacuum arc ionsource. As expected from previous consideration of cathode materials inthe Periodic Table of the Elements, thallium plasma shows lead-likebehavior. Its mean ion charge state exceeds 2.0 immediately after arctriggering, reaches the predicted 1.60 and 1.45 after about 100 microsecand 150 microsec, respectively. The most likely ion velocity is initially8000 m/s and decays to 6500 m/s and 6200 m/s after 100 microsec and 150microsec, respectively. Both ion charge states and ion velocities decayfurther towards steady state values, which are not reached within the 300microsec pulses used here. It is argued that the exceptionally high vaporpressure and charge exchange reactions are associated with theestablishment of steady state ion values.

Yushkov, Georgy Yu.; Anders, Andre

2006-10-02T23:59:59.000Z

319

Electrical Safety and Arc Flash Protections  

SciTech Connect (OSTI)

Over the past four years, the Electrical Safety Program at PPPL has evolved in addressing changing regulatory requirements and lessons learned from accident events, particularly in regards to arc flash hazards and implementing NFPA 70E requirements. This presentation will discuss PPPL's approaches to the areas of electrical hazards evaluation, both shock and arc flash; engineered solutions for hazards mitigation such as remote racking of medium voltage breakers, operational changes for hazards avoidance, targeted personnel training and hazard appropriate personal protective equipment. Practical solutions for nominal voltage identification and zero voltage checks for lockout/tagout will also be covered. Finally, we will review the value of a comprehensive electrical drawing program, employee attitudes expressed as a personal safety work ethic, integrated safety management, and sustained management support for continuous safety improvement.

R. Camp

2008-03-04T23:59:59.000Z

320

E-Print Network 3.0 - alloys laser welded Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

laser welded Search Powered by Explorit Topic List Advanced Search Sample search results for: alloys laser welded Page: << < 1 2 3 4 5 > >> 1 The influence of laser welding...

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Development of New Ultrasonic Inspection Technique for Spot Welds with Matrix Arrayed Probe and SAFT  

Science Journals Connector (OSTI)

A portable type of 3D ultrasonic inspection system, named “Matrixeye”, was applied to the spot welds, in which a matrix-arrayed probe was used as a sensing unit, and the welding zone in the spot welds was visuali...

T. Ikeda; H. Karasawa; S. Matsumoto; S. Satonaka; C. Iwamoto

2006-05-01T23:59:59.000Z

322

Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds  

SciTech Connect (OSTI)

The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing.

GJ Schuster, FA Simonen, SR Doctor

2008-04-01T23:59:59.000Z

323

Delivery quality assurance with ArcCHECK  

SciTech Connect (OSTI)

Radiation therapy requires delivery quality assurance (DQA) to ensure that treatment is accurate and closely follows the plan. We report our experience with the ArcCHECK phantom and investigate its potential optimization for the DQA process. One-hundred seventy DQA plans from 84 patients were studied. Plans were classified into 2 groups: those with the target situated on the diodes of the ArcCHECK (D plans) and those with the target situated at the center (C plans). Gamma pass rates for 8 target sites were examined. The parameters used to analyze the data included 3%/3 mm with the Van Dyk percent difference criteria (VD) on, 3%/3 mm with the VD off, 2%/2 mm with the VD on, and x/3 mm with the VD on and the percentage dosimetric agreement “x” for diode plans adjusted. D plans typically displayed maximum planned dose (MPD) on the cylindrical surface containing ArcCHECK diodes than center plans, resulting in inflated gamma pass rates. When this was taken into account by adjusting the percentage dosimetric agreement, C plans outperformed D plans by an average of 3.5%. ArcCHECK can streamline the DQA process, consuming less time and resources than radiographic films. It is unnecessary to generate 2 DQA plans for each patient; a single center plan will suffice. Six of 8 target sites consistently displayed pass rates well within our acceptance criteria; the lesser performance of head and neck and spinal sites can be attributed to marginally lower doses and increased high gradient of plans.

Neilson, Christopher; Klein, Michael; Barnett, Rob [London Regional Cancer Program, London Health Sciences Centre, London, Ontario (Canada); Yartsev, Slav, E-mail: slav.yartsev@lhsc.on.ca [London Regional Cancer Program, London Health Sciences Centre, London, Ontario (Canada)

2013-04-01T23:59:59.000Z

324

Mechanical properties of welds in commercial alloys for high-temperature gas-cooled reactor components  

SciTech Connect (OSTI)

Weld properties of Hastelloy-X, Incoloy alloy 800H (with and without Inconel-82 cladding), and 2 1/4 Cr-1 Mo are being studied to provide design data to support the development of steam generator, core auxiliary heat exchanger, and metallic thermal barrier components of the high-temperature gas-cooled reactor (HTGR) steam cycle/cogeneration plant. Tests performed include elevated-temperature creep rupture tests and tensile tests. So far, data from the literature and from relatively short-term tests at GA Technologies Inc. indicate that the weldments are satisfactory for HTGR application.

Lindgren, J.R.; Li, C.C.; Ryder, R.H.; Thurgood, B.E.

1984-07-01T23:59:59.000Z

325

TEAM HEV ARC HITECTURE ENGIN E FU EL TRANS MISSION EN ERGY STOR  

Broader source: Energy.gov (indexed) [DOE]

TEAM TEAM HEV ARC HITECTURE ENGIN E FU EL TRANS MISSION EN ERGY STOR AGE MO TOR Michigan Technological University Through-the-road Parallel 2.0-L 4 Cylinder Spark Ignition Reformulated Gasoline 4-speed Automatic COBASYS, Nickel Metal Hydride - 288V 50 kW Solectria AC Induction Transaxle Mississippi State University Through-the-road Parallel 1.9-L GM Direct Injection Turbo Diesel Bio Diesel (B20) GM F40 6-speed Manual Johnson Controls, Nickel Metal Hydride - 330V 45 kW Ballard Integrated Power Transaxle The Ohio State University Through-the-road Parallel 1.9-L GM Direct Injection Turbo Diesel Bio Diesel (B20) Aisin-Warner AF40 6-speed Automatic Transaxle Panasonic, Nickel Metal Hydride - 300V 67 kW Ballard AC Induction Transaxle /10.6 kW Kollmorgen Brushless DC Generator Pennsylvania State

326

Develop baseline computational model for proactive welding stress  

Broader source: Energy.gov (indexed) [DOE]

Develop baseline computational model for proactive welding stress Develop baseline computational model for proactive welding stress management to suppress helium induced cracking during weld repair Develop baseline computational model for proactive welding stress management to suppress helium induced cracking during weld repair There are over 100 nuclear power plants operating in the U.S., which generate approximately 20% of the nation's electricity. These plants range from 15 to 40 years old. Extending the service lives of the current fleet of nuclear power plants beyond 60 years is imperative to allow for the environmentally-sustainable energy infrastructure being developed and matured. Welding repair of irradiated nuclear reactor materials (such as austenitic stainless steels) is especially challenging because of the

327

Process-control in laser welding utilising optical signal oscillations  

SciTech Connect (OSTI)

The authors describe an optical sensor for process monitoring of Nd:YAG laser welding. This sensor detects the broadband radiation produced by the welding process, dividing it into broad spectral bands (designated as UV/visible and IR). Fourier analysis is used to investigate an oscillatory intensity modulation of the optical signals, believed to arise from a combination of keyhole and weld pool oscillations. The spectral content of the oscillations may be used to detect a fully open welding keyhole, and determine work-piece thickness in this welding regime. These oscillations have also been utilized in the construction of a seam tracking system which allows the authors to follow the seam of a lap-weld. Additional signal processing also allows optimum positioning of the laser spot.

Haran, F.M.; Hand, D.P.; Jones, J.D.C. [Heriot-Watt Univ., Edinburgh (United Kingdom)] [and others

1996-12-31T23:59:59.000Z

328

Influence of wet underwater welding on fracture values  

SciTech Connect (OSTI)

The fracture behavior of welds is influenced by residual stresses. The influence of residual stresses on fracture parameters is investigated through the comparison of wet underwater welds, dry welds and welds without residual stresses. The fracture parameters for a sharp, stationary crack on the surface of a bead on plate weld under bending are determined by the finite element method. The geometric influence of weld on fracture parameters is investigated. The stress intensity factor for linear elastic fracture mechanics, the J-integral and the crack tip opening displacement for plastic fracture mechanics are calculated. The material behavior is assumed as linear elastic or linear elastic/ideal plastic or elastic plastic with multilinear isotropic hardening. The numerical data are compared with the experiments.

Lindhorst, L.; Hamann, R.; Mahrenholtz, O. [Technical Univ. of Hamburg-Harburg, Hamburg (Germany). Offshore Engineering Section 2; Kocak, M. [GKSS Research Center, Geesthacht (Germany). Inst. of Material Research

1995-12-31T23:59:59.000Z

329

Neutron Diffraction Residual Strain Tensor Measurements Within The Phase IA Weld Mock-up Plate P-5  

SciTech Connect (OSTI)

Oak Ridge National Laboratory (ORNL) has worked with NRC and EPRI to apply neutron and X-ray diffraction methods to characterize the residual stresses in a number of dissimilar metal weld mockups and samples. The design of the Phase IA specimens aimed to enable stress measurements by several methods and computational modeling of the weld residual stresses. The partial groove in the 304L stainless steel plate was filled with weld beads of Alloy 82. A summary of the weld conditions for each plate is provided in Table 1. The plates were constrained along the long edges during and after welding by bolts with spring-loaded washers attached to the 1-inch thick Al backing plate. The purpose was to avoid stress relief due to bending of the welded stainless steel plate. The neutron diffraction method was one of the methods selected by EPRI for non-destructive through thickness strain and stress measurement. Four different plates (P-3 to P-6) were studied by neutron diffraction strain mapping, representing four different welding conditions. Through thickness neutron diffraction strain mappings at NRSF2 for the four plates and associated strain-free d-zero specimens involved measurement along seven lines across the weld and at six to seven depths. The mountings of each plate for neutron diffraction measurements were such that the diffraction vector was parallel to each of the three primary orthogonal directions of the plate: two in-plane directions, longitudinal and transverse, and the direction normal to the plate (shown in left figure within Table 1). From the three orthogonal strains for each location, the residual stresses along the three plate directions were calculated. The principal axes of the strain and stress tensors, however, need not necessarily align with the plate coordinate system. To explore this, plate P-5 was selected for examination of the possibility that the principal axes of strain are not along the sample coordinate system axes. If adequate data could be collected the goal would be to determine the strain tensor's orientation and magnitude of strain along each principle axis direction.

Hubbard, Camden R [ORNL

2011-09-01T23:59:59.000Z

330

Volumetric modulated arc radiotherapy for esophageal cancer  

SciTech Connect (OSTI)

A treatment planning study was performed to evaluate the performance of volumetric arc modulation with RapidArc (RA) against 3D conformal radiation therapy (3D-CRT) and conventional intensity-modulated radiation therapy (IMRT) techniques for esophageal cancer. Computed tomgraphy scans of 10 patients were included in the study. 3D-CRT, 4-field IMRT, and single-arc and double-arc RA plans were generated with the aim to spare organs at risk (OAR) and healthy tissue while enforcing highly conformal target coverage. The planning objective was to deliver 54 Gy to the planning target volume (PTV) in 30 fractions. Plans were evaluated based on target conformity and dose-volume histograms of organs at risk (lung, spinal cord, and heart). The monitor unit (MU) and treatment delivery time were also evaluated to measure the treatment efficiency. The IMRT plan improves target conformity and spares OAR when compared with 3D-CRT. Target conformity improved with RA plans compared with IMRT. The mean lung dose was similar in all techniques. However, RA plans showed a reduction in the volume of the lung irradiated at V{sub 20Gy} and V{sub 30Gy} dose levels (range, 4.62-17.98%) compared with IMRT plans. The mean dose and D{sub 35%} of heart for the RA plans were better than the IMRT by 0.5-5.8%. Mean V{sub 10Gy} and integral dose to healthy tissue were almost similar in all techniques. But RA plans resulted in a reduced low-level dose bath (15-20 Gy) in the range of 14-16% compared with IMRT plans. The average MU needed to deliver the prescribed dose by RA technique was reduced by 20-25% compared with IMRT technique. The preliminary study on RA for esophageal cancers showed improvements in sparing OAR and healthy tissue with reduced beam-on time, whereas only double-arc RA offered improved target coverage compared with IMRT and 3D-CRT plans.

Vivekanandan, Nagarajan, E-mail: viveknaren@hotmail.com [Department of Medical Physics, Cancer Institute, Chennai (India); Sriram, Padmanaban; Syam Kumar, S.A.; Bhuvaneswari, Narayanan; Saranya, Kamalakannan [Department of Medical Physics, Cancer Institute, Chennai (India)

2012-04-01T23:59:59.000Z

331

Industry standards catch up with in-service welding  

SciTech Connect (OSTI)

Welding onto a pipeline after it has been put into service, a practice commonly referred to as hot tap welding, is frequently required for several reasons. Repair sleeves are installed to reinforce areas of corrosion or mechanical damage, and branch connections are made for system modifications. There are often significant economic incentives to perform this welding without removing the system from service. Operations are maintained during welding and the pipe's contents are not vented into the atmosphere. Due to technological advances in in-service welding, industry needed an update to standards and recommended practices. This year, the American Petroleum Institute (API) hopes to meet that need. The 19th edition of API Standard 1104--Welding of Pipelines and Related Facilities, includes a new appendix that pertains to in-service welding. Appendix B, In-Service Welding, is intended to eventually replace API Recommended Practice 1107--Pipeline Maintenance Welding Practices. API 1107, which was introduced in 1966 and updated in 1987 and 1991, is intended to provide recommended practices for pipeline maintenance welding. The current third edition approached its mandatory five-year review in 1996 by the API-AGA Joint Committee on Oil and Gas Pipeline Field Welding Practices, which also maintains API 1104. The committee saw 11078 needed to reflect the updates that had been made to 1104 as well as the technological advances for in-service welding. To alleviate redundancy between the two documents, and to alleviate lag time between updates, the committee approved a proposal to update and incorporate requirements of API 1107 into an appendix of API 1104. In the meantime, the third edition of API 1107 was reapproved for another five-year review cycle.

Bruce, W.A.

1999-11-01T23:59:59.000Z

332

E-Print Network 3.0 - automatic welding Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Centre de mathmatiques Collection: Mathematics 34 Automated system for welding-based rapid prototyping Summary: Automated system for welding-based rapid prototyping Yu Ming...

333

Weld monitor and failure detector for nuclear reactor system  

DOE Patents [OSTI]

Critical but inaccessible welds in a nuclear reactor system are monitored throughout the life of the reactor by providing small aperture means projecting completely through the reactor vessel wall and also through the weld or welds to be monitored. The aperture means is normally sealed from the atmosphere within the reactor. Any incipient failure or cracking of the weld will cause the environment contained within the reactor to pass into the aperture means and thence to the outer surface of the reactor vessel where its presence is readily detected.

Sutton, Jr., Harry G. (Mt. Lebanon, PA)

1987-01-01T23:59:59.000Z

334

Fracture of welded aluminum thin-walled structures  

E-Print Network [OSTI]

A comprehensive methodology was developed in the thesis for damage prediction of welded aluminum thin-walled structures, which includes material modeling, calibration, numerical simulation and experimental verification. ...

Zheng, Li, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

335

Friction Stir Spot Welding of Advanced High Strength Steels II...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

II Friction Stir Spot Welding of Advanced High Strength Steels II 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle Technologies Program Annual Merit Review and Peer Evaluation...

336

SF 2001-WLD;CONTRACTOR WELDING, CUTTING AND BRAZING  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

closet, manhole sewer, confined space and activity. Example: Bldg 890 mechanical room steam line piping that runs thru ceiling space requires overhead welding: SF 2001-WLD...

337

NDE and DE of PWSCC Found in the J-Groove Weld of a Removed-From-Service Control Rod Drive Mechanism  

SciTech Connect (OSTI)

Studies conducted at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington focused on assessing the effectiveness of nondestructive examination (NDE) techniques for inspecting control rod drive mechanism (CRDM) nozzles and J-groove weldments. The primary objective of this work is to provide information to the United States Nuclear Regulatory Commission (US NRC) on the effectiveness of NDE methods as related to the in-service inspection of CRDM nozzles and J-groove weldments, and to enhance the knowledge base of primary water stress corrosion cracking (PWSCC) through destructive characterization of the CRDM assemblies. Two CRDM assemblies were removed from service, decontaminated, and then used in a series of laboratory NDE and DE measurements; this report addresses the following questions: 1) What did each NDE technique detect?, 2) What did each NDE technique miss?, 3) How accurately did each NDE technique characterize the detected flaws?, and finally 4) What were the basis for the NDE techniques performance? Two CRDM assemblies including the CRDM nozzle, the J-groove weld, buttering, and a portion of the ferritic head material were selected for this study. This paper focuses on a CRDM assembly that contained suspected PWSCC, based on in-service inspection data and through-wall leakage. The laboratory NDE measurements used to examine the CRDM assembly followed standard industry techniques for conducting in-service inspections of CRDM nozzles and the crown of the J-groove welds and buttering. These techniques included eddy current testing, time of flight diffraction ultrasound, and penetrant testing. In addition, other laboratory-based NDE methods were employed to conduct inspections of the CRDM assembly with particular emphasis on inspecting the J-groove weld and buttering. These techniques included volumetric ultrasonic inspection of the J-groove weld metal, visual testing via replicant material of the J-groove weld and high resolution photography of the J-groove weld crown and buttering. The results from these NDE studies were used to guide the development of the destructive characterization plan. The NDE studies found several crack-like indications. The NDE and DE studies determined that one of these was a through-weld radially-oriented PWSCC crack in the wetted surface of the J-groove weld, located at the transition point between the weld and the buttering. The crack was 6 mm long on the surface and quickly grew to 25 mm long at a depth of 8 mm, covering the length of the weld between the penetration tube and the carbon steel. The NDE studies found that only ET was able to detect the through-weld crack. The crack was oriented poorly for the ultrasonic testing, and was too tight for accurate PT or VT. The ET voltage response of the flaw was 30% that of a deep EDM notch. The DE performed on the crack consisted of slicing the crack into thin sections, polishing the sections, and then using optical and scanning electron microscopy (SEM) to characterize the crack. DE shows the crack was PWSCC and that it initiated on the wetted surface, grew and expanded through the weld metal, and exited into the annulus. The SEM examinations showed the crack followed the weld grain boundaries as it progressed through the weld. The crack was branched and discontinuous along its length.

Cumblidge, Stephen E.; Doctor, Steven R.; Schuster, George J.; Harris, Rob; Crawford, Susan L.; Seffens, Rob J.; Toloczko, Mychailo B.; Bruemmer, Stephen M.

2008-01-01T23:59:59.000Z

338

Method Of Bonding A Metal Connection To An Electrode Including A Core Having A Fiber Or Foam Type Structure For An Electrochemical Cell, An  

SciTech Connect (OSTI)

A method of bonding a metal connection to an electrode including a core having a fiber or foam-type structure for an electrochemical cell, in which method at least one metal strip is pressed against one edge of the core and is welded thereto under compression, wherein, at least in line with the region in which said strip is welded to the core, which is referred to as the "main core", a retaining core of a type analogous to that of the main core is disposed prior to the welding.

Loustau, Marie-Therese (Bordeaux, FR); Verhoog, Roelof (Bordeaux, FR); Precigout, Claude (Lormont, FR)

1996-09-24T23:59:59.000Z

339

Arc Flash Boundary Calculations Using Computer Software Tools  

SciTech Connect (OSTI)

Arc Flash Protection boundary calculations have become easier to perform with the availability of personal computer software. These programs incorporate arc flash protection boundary formulas for different voltage and current levels, calculate the bolted fault current at each bus, and use built in time-current coordination curves to determine the clearing time of protective devices in the system. Results of the arc flash protection boundary calculations can be presented in several different forms--as an annotation to the one-line diagram, as a table of arc flash protection boundary distances, and as printed placards to be attached to the appropriate equipment. Basic arc flash protection boundary principles are presented in this paper along with several helpful suggestions for performing arc flash protection boundary calculations.

Gibbs, M.D.

2005-01-07T23:59:59.000Z

340

Physics of arcing, and implications to sputter deposition  

SciTech Connect (OSTI)

Arcing is a well-known, unwanted discharge regime observed on the surface of sputtering targets. The discharge voltage breaks down to less than 50 V while the current jumps to elevated levels. Arcing is unwanted because it prevents uniform deposition and creates particulates. The issue of arcing has been dealt with by target surface conditioning and by using modern power supplies that have arc suppression incorporated. With increasing quality requirements in terms of uniformity of coatings, and absence of particulates, especially for electrochromic and other advanced coatings applications, the issue of arcing warrants a closer examination with the goal to find other, physics-based, and hopefully better approaches of arcing prevention. From a physics point of view, the onset of arcing is nothing else than the transition of the discharge to a cathodic arc mode, which is characterized by the ignition of non-stationary arc spots. Arc spots operate by a sequence of microexplosions, enabling explosive electron emission, as opposed to secondary electron emission. Arc spots and their fragments have a size distribution in the micrometer and sub-micrometer range, and a characteristic time distribution that has components shorter than microseconds. Understanding the ignition conditions of arc spots are of central physical interest. Spot ignition is associated with electric field enhancement, which can be of geometric nature (roughness,particles), or chemical nature (e.g. oxide formation) and related local accumulation of surface charge. Therefore, it is clear that these issues are of particular concern when operating with high-density plasmas, such as in high-power pulsed sputtering, and when using reactive sputter gases.

Anders, Andre

2003-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Shapes of Spectral Lines of Nonuniform Plasma of Electric Arc Discharge Between Copper Electrodes  

SciTech Connect (OSTI)

The radial profiles of the temperature and electron density in the plasma of the free burning electric arc between copper electrodes are studied by optical spectroscopy techniques. The electron density and the temperature in plasma as initial parameters were used in the calculation of the plasma composition in local thermodynamic equilibrium (LTE) assumption. We used the Saha's equation for copper, nitrogen and oxygen, dissociation equation for nitrogen and oxygen, the equation of plasma electrical neutrality and Dalton's law as well. So, it would be possible to determine the amounts of metal vapours in plasma.

Babich, Ida L.; Boretskij, Viacheslav F.; Veklich, Anatoly N. [Radiophysics Faculty, Taras Shevchenko Kyiv National University, 64, Volodymyrs'ka Str., Kyiv 01033 (Ukraine)

2007-09-28T23:59:59.000Z

342

Influence of argon and oxygen on charge-state-resolved ion energy distributions of filtered aluminum arcs  

E-Print Network [OSTI]

energy distributions of filtered aluminum arcs Johanna Roséndistributions (IEDs) in filtered aluminum vacuum arc plasmasfor vacuum arc plasmas. Aluminum plasma, for example,

Rosen, Johanna; Anders, Andre; Mraz, Stanislav; Atiser, Adil; Schneider, Jochen M.

2006-01-01T23:59:59.000Z

343

A Miocene Island-Arc Volcanic Seamount- The Takashibiyama Formation...  

Open Energy Info (EERE)

Island-Arc Volcanic Seamount- The Takashibiyama Formation, Shimane Peninsula, Sw Japan Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: A...

344

Stabilization of Electrocatalytic Metal Nanoparticles at Metal...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Electrocatalytic Metal Nanoparticles at Metal-Metal Oxide-Graphene Triple Junction Points. Stabilization of Electrocatalytic Metal Nanoparticles at Metal-Metal Oxide-Graphene...

345

Arc plasma generator of atomic driver for steady-state negative ion source  

SciTech Connect (OSTI)

The paper reviews the results of development of steady-state arc-discharge plasma generator with directly heated LaB{sub 6} cathode. This arc-discharge plasma generator produces a plasma jet which is to be converted into an atomic one after recombination on a metallic plate. The plate is electrically biased relative to the plasma in order to control the atom energies. Such an intensive jet of hydrogen atoms can be used in negative ion sources for effective production of negative ions on a cesiated surface of plasma grid. All elements of the plasma generator have an augmented water cooling to operate in long pulse mode or in steady state. The thermo-mechanical stresses and deformations of the most critical elements of the plasma generator were determined by simulations. Magnetic field inside the discharge chamber was optimized to reduce the local power loads. The first tests of the steady-state arc plasma generator prototype have performed in long-pulse mode.

Ivanov, A. A.; Belchenko, Yu. I.; Davydenko, V. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation) [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation); Ivanov, I. A.; Kolmogorov, V. V.; Listopad, A. A., E-mail: a.a.listopad@inp.nsk.su; Mishagin, V. V.; Shulzhenko, G. I. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)] [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Putvinsky, S. V.; Smirnov, A. [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)] [Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688 (United States)

2014-02-15T23:59:59.000Z

346

A New Survey for Giant Arcs  

SciTech Connect (OSTI)

We report on the first results of an imaging survey to detect strong gravitational lensing targeting the richest clusters selected from the photometric data of the Sloan Digital Sky Survey (SDSS) with follow-up deep imaging observations from the Wisconsin Indiana Yale NOAO (WIYN) 3.5m telescope and the University of Hawaii 88-inch telescope (UH88). The clusters are selected from an area of 8000 deg{sup 2} using the Red Cluster Sequence technique and span the redshift range 0.1 {approx}< z {approx}< 0.6, corresponding to a comoving cosmological volume of {approx} 2Gpc{sup 3}. Our imaging survey thus targets a volume more than an order of magnitude larger than any previous search. A total of 240 clusters were imaged of which 141 had sub-arcsecond image quality. Our survey has uncovered 16 new lensing clusters with definite giant arcs, an additional 12 systems for which the lensing interpretation is very likely, and 9 possible lenses which contain shorter arclets or candidate arcs which are less certain and will require further observations to confirm their lensing origin. The number of new cluster lenses detected in this survey is likely > 30. Among these new systems are several of the most dramatic examples of strong gravitational lensing ever discovered with multiple bright arcs at large angular separation. These will likely become 'poster-child' gravitational lenses similar to Abell 1689 and CL0024+1654. The new lenses discovered in this survey will enable future systematic studies of the statistics of strong lensing and its implications for cosmology and our structure formation paradigm.

Hennawi, Joseph F.; Gladders, Michael D.; Oguri, Masamune; Dalal, Neal; Koester, Benjamin; Natarajan, Priyamvada; Strauss, Michael A.; Inada, Naohisa; Kayo, Issha; Lin,; Lampeitl, Hubert; Annis, James; Bahcall, Neta A.; Schneider, Donald P.

2006-11-15T23:59:59.000Z

347

A survey of repair practices for nuclear power plant containment metallic pressure boundaries  

SciTech Connect (OSTI)

The Nuclear Regulatory Commission has initiated a program at the Oak Ridge National Laboratory to provide assistance in their assessment of the effects of potential degradation on the structural integrity and leaktightness of metal containment vessels and steel liners of concrete containments in nuclear power plants. One of the program objectives is to identify repair practices for restoring metallic containment pressure boundary components that have been damaged or degraded in service. This report presents issues associated with inservice condition assessments and continued service evaluations and identifies the rules and requirements for the repair and replacement of nonconforming containment pressure boundary components by welding or metal removal. Discussion topics include base and welding materials, welding procedure and performance qualifications, inspection techniques, testing methods, acceptance criteria, and documentation requirements necessary for making acceptable repairs and replacements so that the plant can be returned to a safe operating condition.

Oland, C.B.; Naus, D.J. [Oak Ridge National Lab., TN (United States)

1998-05-01T23:59:59.000Z

348

WELDING RESEARCH JUNE 2007, VOL. 86-s170  

E-Print Network [OSTI]

resistance, Fe-Al weld cladding is susceptible to cracking due to hydrogen embrittlement at elevated aluminum cracking of FeAl and Fe3Al intermetallics is due to hydrogen embrittlement. In that work, the room investigated the effect of chromium on the hydrogen cracking susceptibility of Fe-Al weld cladding. The results

DuPont, John N.

349

Joining aluminum to titanium alloy by friction stir lap welding with cutting pin  

SciTech Connect (OSTI)

Aluminum 1060 and titanium alloy Ti-6Al-4V plates were lap joined by friction stir welding. A cutting pin of rotary burr made of tungsten carbide was employed. The microstructures of the joining interface were observed by scanning electron microscopy. Joint strength was evaluated by a tensile shear test. During the welding process, the surface layer of the titanium plate was cut off by the pin, and intensively mixed with aluminum situated on the titanium plate. The microstructures analysis showed that a visible swirl-like mixed region existed at the interface. In this region, the Al metal, Ti metal and the mixed layer of them were all presented. The ultimate tensile shear strength of joint reached 100% of 1060Al that underwent thermal cycle provided by the shoulder. - Highlights: Black-Right-Pointing-Pointer FSW with cutting pin was successfully employed to form Al/Ti lap joint. Black-Right-Pointing-Pointer Swirl-like structures formed due to mechanical mixing were found at the interface. Black-Right-Pointing-Pointer High-strength joints fractured at Al suffered thermal cycle were produced.

Wei, Yanni [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 (China) [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 (China); Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China); Li, Jinglong, E-mail: lijinglg@nwpu.edu.cn [Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China)] [Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China); Xiong, Jiangtao [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 (China) [State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 (China); Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China); Huang, Fu; Zhang, Fusheng; Raza, Syed Hamid [Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China)] [Shaanxi Key Laboratory of Friction Welding Technologies, Northwestern Polytechnical University, Xi'an 710072 (China)

2012-09-15T23:59:59.000Z

350

Grain boundary defects initiation at the outer surface of dissimilar welds: Corrosion mechanism studies  

SciTech Connect (OSTI)

Dissimilar welds located on the primary coolant system of the French PWR plants exhibit grain boundary defects in the true austenitic zones of the first buttering layer. If grain boundaries reach the interface, they can extend to the martensitic band. Those defects are filled with compact oxides. In addition, the ferritic base metal presents some pits along the interface. Nowadays, three mechanisms are proposed to explain the initiation of those defects: stress corrosion cracking, intergranular corrosion and high temperature intergranular oxidation. This paper is dealing with the study of the mechanisms involved in the corrosion phenomenon. Intergranular corrosion tests performed on different materials show that only the first buttering layer, even with some {delta} ferrite, is sensitized. The results of stress corrosion cracking tests in water solutions show that intergranular cracking is possible on a bulk material representative of the first buttering layer. It is unlikely on actual dissimilar welds where the ferritic base metal protects the first austenitic layer by galvanic coupling. Therefore, the stress corrosion cracking assumption cannot explain the initiation of the defects in aqueous environment. The results of the investigations and of the corrosion studies led to the conclusion that the atmosphere could be the only possible aggressive environment. This conclusion is based on natural atmospheric exposure and accelerated corrosion tests carried out with SO{sub 2} additions in controlled atmosphere. They both induce a severe intergranular corrosion on true sensitized austenitic materials.

Bouvier, O. De; Yrieix, B. [Electricite De France, Moret Sur Loing (France). Research and Development Division

1995-12-31T23:59:59.000Z

351

E-Print Network 3.0 - arc magmatism isotopic Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

& Nakamura (1993) Nature 370 e.g. Izu arc: Ishikawa & Nakamura (1993) Nature 370 Boron isotopes help... --Th isotopes in arc magmasTh isotopes in arc magmas For equilibrium:...

352

E-Print Network 3.0 - arc northwesternmost california Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

365 ARC JIW Engineering Design Requirements (4... 201 2. ARC 203 2. ARC 204 (studio) 3. PHY 103 3. PHY ... Source: Bou-Zeid, Elie - Department of Civil and Environmental...

353

E-Print Network 3.0 - arc detector system Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

by hand later) Summary: . The spatial resolution is approximately 1 arc sec in the E-W direction and 2 arc sec along the slit (N... ,0) (3,0) (0,910) Slit n ? (arc sec 2 ) ...

354

E-Print Network 3.0 - assisted non-consumable arc Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Sample search results for: assisted non-consumable arc Page: << < 1 2 3 4 5 > >> 1 GIS by ESRITM What is ArcGIS Summary: GIS by ESRITM What is ArcGIS TM ? 12;Copyright ...

355

E-Print Network 3.0 - arc dynamic behavior Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Search Sample search results for: arc dynamic behavior Page: << < 1 2 3 4 5 > >> 1 GIS by ESRITM What is ArcGIS Summary: and events Dynamic segmentation Importing ArcView GIS...

356

Creep and tensile properties of alloy 800H-Hastelloy X weldments. [HTGR  

SciTech Connect (OSTI)

Hastelloy X and alloy 800H were joined satisfactorily by the gas tungsten arc welding process with ERNiCr-3 filler and the shielded metal arc welding process with Inco Weld A filler. Test specimens were of two types: (1) made entirely of deposited Inco Weld A and (2) machined transverse across the weldments to include Hastelloy X, filler metal (ERNiCr-3 or Inco Weld A), and alloy 800H. They were aged 2000 and 10,000 h and subjected to short-term tensile and creep tests. Inco Weld A and ERNiCr-3 are both suitable filler metals and result in welds that are stronger than the alloy 800H base metal.

McCoy, H. E.; King, J. F.

1983-08-01T23:59:59.000Z

357

F i W ldi PFusion Welding -Processes ME 6222: Manufacturing Processes and Systems  

E-Print Network [OSTI]

Overview · Types of fusion welding ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2009 3 #12Summary · Types of fusion welding ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2009 25 #12.S. Colton © GIT 2009 1 #12;Fusion weldingFusion welding · Intimate interfacial contact by using a liquid

Colton, Jonathan S.

358

17 The Intelligent Welding Gun: Augmented Reality for Experimental Vehicle Construction  

E-Print Network [OSTI]

17 The Intelligent Welding Gun: Augmented Reality for Experimental Vehicle Construction Florian presents the prototypical design and implementation of an Intelligent Welding Gun to help welders is the Intelligent Welding Gun ­ a regular welding gun with a display attachment, a few buttons for user in

Bruegge, Bernd

359

Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine  

E-Print Network [OSTI]

Numerical simulations of welds of thick steel pieces of interest for the thermonuclear fusion ITER machine

Carmignani, B

2005-01-01T23:59:59.000Z

360

Building A Simulation Model For The Prediction Of Temperature Distribution In Pulsed Laser Spot Welding Of Dissimilar Low Carbon Steel 1020 To Aluminum Alloy 6061  

SciTech Connect (OSTI)

This paper describes the development of a computer model used to analyze the heat flow during pulsed Nd: YAG laser spot welding of dissimilar metal; low carbon steel (1020) to aluminum alloy (6061). The model is built using ANSYS FLUENT 3.6 software where almost all the environments simulated to be similar to the experimental environments. A simulation analysis was implemented based on conduction heat transfer out of the key hole where no melting occurs. The effect of laser power and pulse duration was studied.Three peak powers 1, 1.66 and 2.5 kW were varied during pulsed laser spot welding (keeping the energy constant), also the effect of two pulse durations 4 and 8 ms (with constant peak power), on the transient temperature distribution and weld pool dimension were predicated using the present simulation. It was found that the present simulation model can give an indication for choosing the suitable laser parameters (i.e. pulse durations, peak power and interaction time required) during pulsed laser spot welding of dissimilar metals.

Yousef, Adel K. M. [Faculty of Engineering , University of Diyala, Diyala-Baqouba (Iraq); Taha, Ziad A.; Shehab, Abeer A. [Institute of laser for postgraduate studies, Baghdad University, Baghdad (Iraq)

2011-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Arc Geometry and Algebra: Foliations, Moduli Spaces, String ...  

E-Print Network [OSTI]

exhaustive if wti(?) = 0 for all i. We set Arcs g(r ?1) ? As g,r and DArcs g(r ?1) ? Ds g,r to be the subsets of exhaustive elements. We furthermore set Arc(n) = ?g,

2012-05-02T23:59:59.000Z

362

Connecting ARC/INFO and SNACTor Project Report  

E-Print Network [OSTI]

Connecting ARC/INFO and SNACTor Project Report June 1991 Stuart C. Shapiro, Hans Chalupsky;Connecting ARC/INFO* and SNACTor --- Project Report1 Stuart C. Shapiro2 , Hans Chalupsky2 and Hsueh and reasoning system developed by Stuart C. Shapiro et al. at the State University of New York at Buffalo

California at Santa Barbara, University of

363

Mechanism of carbon nanostructure synthesis in arc plasma  

SciTech Connect (OSTI)

Plasma enhanced techniques are widely used for synthesis of carbon nanostructures. The primary focus of this paper is to summarize recent experimental and theoretical advances in understanding of single-wall carbon nanotube (SWNT) synthesis mechanism in arcs, and to describe methods of controlling arc plasma parameters. Fundamental issues related to synthesis of SWNTs, which is a relationship between plasma parameters and SWNT characteristics are considered. It is shown that characteristics of synthesized SWNTs can be altered by varying plasma parameters. Effects of electrical and magnetic fields applied during SWNT synthesis in arc plasma are explored. Magnetic field has a profound effect on the diameter, chirality, and length of a SWNT synthesized in the arc plasma. An average length of SWNT increases by a factor of 2 in discharge with magnetic field and an amount of long nanotubes with the length above 5 {mu}m also increases in comparison with that observed in the discharge without a magnetic field. In addition, synthesis of a few-layer graphene in a magnetic field presence is discovered. A coupled model of plasma-electrode phenomena in atmospheric-pressure anodic arc in helium is described. Calculations indicate that substantial fraction of the current at the cathode is conducted by ions (0.7-0.9 of the total current). It is shown that nonmonotonic behavior of the arc current-voltage characteristic can be reproduced taking into account the experimentally observed dependence of the arc radius on arc current.

Keidar, M.; Shashurin, A.; Volotskova, O. [George Washington University, Washington, DC 20052 (United States); Raitses, Y. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Beilis, I. I. [Tel Aviv University, Tel Aviv 69978 (Israel)

2010-05-15T23:59:59.000Z

364

Quiz # 7, STAT 383, Prof. Suman Sanyal, April 8, 2009 (Q2, Page 354) To decide whether the pipe welds in a nuclear power plant meet  

E-Print Network [OSTI]

welds in a nuclear power plant meet specifications, a random sample of welds is to be selected : µ nuclear power plants is to determine if welds

Sanyal, Suman

365

Darwin: The Third DOE ARM TWP ARCS Site  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Darwin: The Third DOE ARM TWP ARCS Site Darwin: The Third DOE ARM TWP ARCS Site W. E. Clements and L. Jones Los Alamos National Laboratory, Los Alamos, New Mexico T. Baldwin Special Services Unit Australian Bureau of Meteorology Melbourne, Australia K. Nitschke South Pacific Regional Environment Programme Apia, Samoa Introduction The U.S. Department of Energy's (DOE's) Atmospheric Radiation Measurement (ARM) Program began operations in its Tropical Western Pacific (TWP) locale in October 1996 when the first Atmospheric Radiation and Cloud Station (ARCS) began collecting data on Manus Island in Papua New Guinea (PNG). Two years later, in November 1998 a second ARCS began operations on the island of Nauru in the Central Pacific. Now a third ARCS has begun collecting data in Darwin, Australia. See Figure 1 for

366

Metal Aminoboranes  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Metal Aminoboranes Metal Aminoboranes Metal Aminoboranes Metal aminoboranes of the formula M(NH.sub.2BH.sub.3).sub.n have been synthesized. June 25, 2013 Metal Aminoboranes Metal aminoboranes of the formula M(NH.sub.2BH.sub.3).sub.n have been synthesized. Available for thumbnail of Feynman Center (505) 665-9090 Email Metal Aminoboranes Metal aminoboranes of the formula M(NH.sub.2BH.sub.3).sub.n have been synthesized. Metal aminoboranes are hydrogen storage materials. Metal aminoboranes are also precursors for synthesizing other metal aminoboranes. Metal aminoboranes can be dehydrogenated to form hydrogen and a reaction product. The reaction product can react with hydrogen to form a hydrogen storage material. Metal aminoboranes can be included in a kit. U.S. Patent No.: 7,713,506 (DOE S-112,798)

367

Type A Investigation of the Electrical Arc Injury at the Stanford...  

Office of Environmental Management (EM)

of the Electrical Arc Injury at the Stanford Linear Accelerator Complex on October 11, 2004 Type A Investigation of the Electrical Arc Injury at the Stanford Linear Accelerator...

368

E-Print Network 3.0 - area filtered arc Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

of Electrical and Computer Engineering, University of Kentucky Collection: Engineering 3 GIS by ESRITM What is ArcGIS Summary: and terrainmodelingcapabilities. ArcGIS 3D Analyst...

369

E-Print Network 3.0 - andean arc magmatism Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

arc in central Novaya Zemlya, Arctic Russia... - genian magmatic arc. Zircon and titanite in four samples from Mashigin Fjord and Matochkin Strait yield U... ). The events at...

370

An algorithm to calculate a collapsed arc dose matrix in volumetric modulated arc therapy  

SciTech Connect (OSTI)

Purpose: The delivery of volumetric modulated arc therapy (VMAT) is more complex than other conformal radiotherapy techniques. In this work, the authors present the feasibility of performing routine verification of VMAT delivery using a dose matrix measured by a gantry mounted 2D ion chamber array and corresponding dose matrix calculated by an inhouse developed algorithm.Methods: Pinnacle, v9.0, treatment planning system (TPS) was used in this study to generate VMAT plans for a 6 MV photon beam from an Elekta-Synergy linear accelerator. An algorithm was developed and implemented with inhouse computer code to calculate the dose matrix resulting from a VMAT arc in a plane perpendicular to the beam at isocenter. The algorithm was validated using measurement of standard patterns and clinical VMAT plans with a 2D ion chamber array. The clinical VMAT plans were also validated using ArcCHECK measurements. The measured and calculated dose matrices were compared using gamma ({gamma}) analysis with 3%/3 mm criteria and {gamma} tolerance of 1.Results: The dose matrix comparison of standard patterns has shown excellent agreement with the mean {gamma} pass rate 97.7 ({sigma}= 0.4)%. The validation of clinical VMAT plans using the dose matrix predicted by the algorithm and the corresponding measured dose matrices also showed good agreement with the mean {gamma} pass rate of 97.6 ({sigma}= 1.6)%. The validation of clinical VMAT plans using ArcCHECK measurements showed a mean pass rate of 95.6 ({sigma}= 1.8)%.Conclusions: The developed algorithm was shown to accurately predict the dose matrix, in a plane perpendicular to the beam, by considering all possible leaf trajectories in a VMAT delivery. This enables the verification of VMAT delivery using a 2D array detector mounted on a treatment head.

Arumugam, Sankar; Xing Aitang [Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales 2170 (Australia); Jameson, Michael [Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2522 (Australia); Holloway, Lois [Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2522 (Australia); South West Clinical School, University of New South Wales, Sydney, New South Wales 2052 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, New South Wales 2006 (Australia)

2013-07-15T23:59:59.000Z

371

Thermal and molecular investigation of laser tissue welding  

SciTech Connect (OSTI)

Despite the growing number of successful animal and human trials, the exact mechanisms of laser tissue welding remain unknown. Furthermore, the effects of laser heating on tissue on the molecular scale are not fully understood. To address these issues, a multi-front attack oil both extrinsic (solder/patch mediated) and intrinsic (laser only) tissue welding was launched using two-color infrared thermometry, computer modeling, weld strength assessment, biochemical assays, and vibrational spectroscopy. The coupling of experimentally measured surface temperatures with the predictive numerical simulations provided insight into the sub-surface dynamics of the laser tissue welding process. Quantification of the acute strength of the welds following the welding procedure enabled comparison among trials during an experiment, with previous experiments, and with other studies in the literature. The acute weld integrity also provided an indication of tile probability of long-term success. Molecular effects induced In the tissue by laser irradiation were investigated by measuring tile concentrations of specific collagen covalent crosslinks and characterizing the Fourier-Transform infrared (FTIR) spectra before and after the laser exposure.

Small, W., IV

1998-06-01T23:59:59.000Z

372

New development activities in the field of wet welding  

SciTech Connect (OSTI)

The Wet Welding process has now become an interesting alternative repair process due to its high flexibility, its low investment costs and its high versatility. However, due to the prior bad reputation of the in former times achievable low weldment quality, due to extremely high hardness, high porosity, high hydrogen contamination and in combination with this high cracking susceptibility the wet welding process nowadays requires further activities to improve its reputation and credibility. New acceptance criteria, more detailed information on the achievable weldment quality and especially the development of life prediction data for wet welded components are now required. Advanced testing methods are necessary, additional design criteria are to be developed and achievable weldment quality data are to be included in acknowledged and approved standards and recommendations. Only by the provision of such data the credibility of the process and the problem of quality assurance for wet welded joints can be improved. In two comprehensive projects, sponsored by the European Community under the Thermie Programme, process development and new testing procedures have bene procured and are still under progress to generate the required data and new design criteria for the future application of the wet welding process to main components of offshore structures. The water depths in the range of 50 to 100 msw have been selected for the application of the wet welding process to structural components, as these depths include that range of application in which this process can become competitive to the hyperbaric dry welding process. The international trend to mechanize and automate the hyperbaric welding processes in dry environments can even be completed by the application of a semiautomatic wet welding process, which has already shown very promising results. This process is applicable to mechanized systems (e.g. to a wet robot system).

Szelagowski, P.; Osthus, V. [GKSS Research Center, Geesthacht (Germany); Petershagen, H.; Pohl, R. [Univ. Hamburg (Germany). Inst. fuer Schiffbau; Lafaye, G. [Stolt Comex Seaway, S.A., Marseille (France)

1995-12-31T23:59:59.000Z

373

Experimental evidence of chaotic behavior in atmospheric pressure arc discharge  

SciTech Connect (OSTI)

Thermal plasma technology is already playing an important role in the production of new materials, in the destruction of toxic wastes, and in the development of safer and more efficient manufacturing and material processing applications. In free burning as well as in stabilized arc columns, the inherent movement of arc root results in fluctuation in arc voltage. A full knowledge and control over the arc root dynamics can effectively lengthen the life time, drastically improve performance and reliability in arc plasma devices. In this paper, the authors experimentally investigate the fluctuating voltage signals generated from an atmospheric pressure arc discharge produced in a hollow electrode plasma torch. For the first time, analysis of these signals reveal them to exhibit chaotic behavior. The present analysis is supported with real time behavior, phase portraits, power spectra and Lyapunov exponents. Dependence of system behavior on various control parameters is also investigated. This approach is interesting in the sense that it can lead to better understanding of physics for future researches on arc plasma jets and related devices.

Ghorui, S.; Sahasrabudhe, S.N.; Murthy, P.S.S.; Das, A.K.; Venkatramani, N.

2000-02-01T23:59:59.000Z

374

Transport phenomena in metal-halide lamps a poly-diagnostic study  

E-Print Network [OSTI]

/ spectroscopie. Subject headings: gas discharges / metal-halide lamps / plasma diagnostics / plasma properties-halide arc lamps . . . . . . . . . . . 7 1.3 Scope of ThesisTransport phenomena in metal-halide lamps a poly-diagnostic study Tanya Nimalasuriya #12;Copyright

Eindhoven, Technische Universiteit

375

Welding fixture for nuclear fuel pin cladding assemblies  

DOE Patents [OSTI]

A welding fixture for locating a driver sleeve about the open end of a nuclear fuel pin cladding. The welding fixture includes a holder provided with an open cavity having shoulders for properly positioning the driver sleeve, the end cap, and a soft, high temperature resistant plastic protective sleeve that surrounds a portion of the end cap stem. Ejected contaminant particles spewed forth by closure of the cladding by pulsed magnetic welding techniques are captured within a contamination trap formed in the holder for ultimate removal and disposal of contaminating particles along with the holder.

Oakley, David J. (Richland, WA); Feld, Sam H. (West Richland, WA)

1986-01-01T23:59:59.000Z

376

OPTIMIZATION STUDY FOR FILL STEM MANUFACTURINGAND PINCH WELD PROCESSING  

SciTech Connect (OSTI)

A statistically designed experiment was conducted as part of a six sigma project for Fill Stem Manufacturing and Pinch Weld Processing. This multi-year/multi-site project has successfully completed a screening study and used those results as inputs to this optimization study. Eleven welds were made using fairly tight current and cycle range. The welds demonstrate increased burst strength, longer closure length, more net displacement, and improved bond rating with increased current. However, excessive melting remains a concern from a processing viewpoint and may cause adverse metallurgical interactions. Therefore, the highest current levels specified cannot be utilized. A Validation Study is proposed for the Defense Programs Inert Facility.

Korinko, P; Karl Arnold, K

2006-09-06T23:59:59.000Z

377

Robotic equipment for pipeline repair  

SciTech Connect (OSTI)

Hyperbaric welding provides the most reliable method for connection or repair of subsea oil and gas pipelines. Research on hyperbaric arc welding processes indicates that it should be possible to achieve stable welding conditions with Gas Tungsten Arc (GTA) to approximately 600m, and with Gas Metal Arc (GMA) and Plasma Arc to at least 1,000m. These depths are well beyond the limits of manned saturation diving. At the present time the limitation on the maximum depth to which these processes can be applied, in practice, is the requirement for completely diverless operation deeper than approximately 350m. Fully diverless hyperbaric welding is not presently available to the industry but several diverless pipeline repair systems which utilize mechanical connectors have been developed. This paper reviews the present status of mechanized hyperbaric welding systems currently being used in the North Sea and discusses some of the work being done to achieve fully diverless robotic pipeline repair with both welding and connectors.

Gibson, D.E.; Barratt, K.; Paterson, J. [National Hyperbaric Centre, Aberdeen (United Kingdom)

1995-12-31T23:59:59.000Z

378

Weld-Windsor 115-kV Transmission Line Project, Weld County, Colorado  

SciTech Connect (OSTI)

The Western Area Power Administration is proposing to rebuild a 3.0 mile segment of the existing Flatiron-Weld 115-kV transmission line in Weld County. The line would be reconductored with new conductor on new wood pole double circuit structures. The new structures would support a double circuit transmission line configuration. The first circuit would be owned by Western and the second by Public Service Company of Colorado (PSCO). Alternatives considered included no action, constructing PSCO`s circuit on new right-of-way, and reconductoring Western`s existing line on the same structures. The proposed action was selected because it provided an opportunity to share structures with PSCO and, overall, would minimize costs and environmental impacts. The environmental assessment identifies minor effects on existing natural or human resources and minor benefits for agricultural operations.

NONE

1996-05-01T23:59:59.000Z

379

Arc Energy Estimations: Applications in Lightning-Induced Concrete Spall  

SciTech Connect (OSTI)

After lightning contacts a building, the possibility of a physical break in its conductive path to ground may exist. Given such a break, an electric field may develop across the gap until it exceeds the breakdown strength of the non-conducting, or dielectric, material. Breakdown subsequently occurs and energy is dissipated during the development of an arc channel. If the dielectric is concrete, a concern exists that the energy available for arc formation may be capable of launching pieces of spall into sensitive equipment. This paper discusses the mechanisms of energy dissipation in arc formation and quantifies the energy available for concrete spall.

Tully, L K; Ong, M M

2008-06-03T23:59:59.000Z

380

Numerical simulation of carbon arc discharge for nanoparticle synthesis  

SciTech Connect (OSTI)

Arc discharge with catalyst-filled carbon anode in helium background was used for the synthesis of carbon nanoparticles. In this paper, we present the results of numerical simulation of carbon arc discharges with arc current varying from 10 A to 100 A in a background gas pressure of 68 kPa. Anode sublimation rate and current voltage characteristics are compared with experiments. Distribution of temperature and species density, which is important for the estimation of the growth of nanoparticles, is obtained. The probable location of nanoparticle growth region is identified based on the temperature range for the formation of catalyst clusters.

Kundrapu, M.; Keidar, M. [Department of Mechanical and Aerospace Engineering, George Washington University, Washington, DC 20052 (United States)

2012-07-15T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

E-Print Network 3.0 - arc plasma gun Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

gun Search Powered by Explorit Topic List Advanced Search Sample search results for: arc plasma gun...

382

FusionArc optimization: A hybrid volumetric modulated arc therapy (VMAT) and intensity modulated radiation therapy (IMRT) planning strategy  

SciTech Connect (OSTI)

Purpose: To introduce a hybrid volumetric modulated arc therapy/intensity modulated radiation therapy (VMAT/IMRT) optimization strategy called FusionArc that combines the delivery efficiency of single-arc VMAT with the potentially desirable intensity modulation possible with IMRT.Methods: A beamlet-based inverse planning system was enhanced to combine the advantages of VMAT and IMRT into one comprehensive technique. In the hybrid strategy, baseline single-arc VMAT plans are optimized and then the current cost function gradients with respect to the beamlets are used to define a metric for predicting which beam angles would benefit from further intensity modulation. Beams with the highest metric values (called the gradient factor) are converted from VMAT apertures to IMRT fluence, and the optimization proceeds with the mixed variable set until convergence or until additional beams are selected for conversion. One phantom and two clinical cases were used to validate the gradient factor and characterize the FusionArc strategy. Comparisons were made between standard IMRT, single-arc VMAT, and FusionArc plans with one to five IMRT/hybrid beams.Results: The gradient factor was found to be highly predictive of the VMAT angles that would benefit plan quality the most from beam modulation. Over the three cases studied, a FusionArc plan with three converted beams achieved superior dosimetric quality with reductions in final cost ranging from 26.4% to 48.1% compared to single-arc VMAT. Additionally, the three beam FusionArc plans required 22.4%-43.7% fewer MU/Gy than a seven beam IMRT plan. While the FusionArc plans with five converted beams offer larger reductions in final cost-32.9%-55.2% compared to single-arc VMAT-the decrease in MU/Gy compared to IMRT was noticeably smaller at 12.2%-18.5%, when compared to IMRT.Conclusions: A hybrid VMAT/IMRT strategy was implemented to find a high quality compromise between gantry-angle and intensity-based degrees of freedom. This optimization method will allow patients to be simultaneously planned for dosimetric quality and delivery efficiency without switching between delivery techniques. Example phantom and clinical cases suggest that the conversion of only three VMAT segments to modulated beams may result in a good combination of quality and efficiency.

Matuszak, Martha M.; McShan, Daniel L.; Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States); Steers, Jennifer M. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 and Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, Michigan 48109 (United States); Long, Troy; Edwin Romeijn, H. [Department of Industrial and Operations Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States); Fraass, Benedick A. [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California 90048 (United States)

2013-07-15T23:59:59.000Z

383

Friction Stir Spot Welding of Advanced High Strength Steels ...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C. lm14grant.pdf More Documents & Publications Friction Stir Spot Welding of Advanced High...

384

Friction Stir Spot Welding of Advanced High Strength Steels ...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Steels (AHSS) Friction Stir Spot Welding of Advanced High Strength Steels (AHSS) Presentation from the U.S. DOE Office of Vehicle Technologies "Mega" Merit Review 2008 on February...

385

SAFT Imaging of Transverse Cracks in Austenitic and Dissimilar Welds  

Science Journals Connector (OSTI)

Up to now there is no sufficient technique to detect transverse cracks in austenitic and dissimilar welds which recently are of increasing interest in the integrity surveillance of nuclear power plants as well as...

Christian Höhne; Sanjeevareddy Kolkoori…

2013-03-01T23:59:59.000Z

386

Final Scientific/Technical Report "Arc Tube Coating System for Color Consistency"  

SciTech Connect (OSTI)

DOE has enabled the use of coating materials using low cost application methods on light sources to positively affect the output of those sources. The coatings and light source combinations have shown increased lumen output of LED fixtures (1.5%-2.0%), LED arrays (1.4%) and LED powered remote phosphor systems â?? Philips L-Prize lamp (0.9%). We have also demonstrated lifetime enhancements (3000 hrs vs 8000 hrs) and shifting to higher CRI (51 to 65) in metal halide high intensity discharge lamps with metal oxide coatings. The coatings on LEDs and LED products are significant as the market is moving increasingly more towards LED technology. Enhancements in LED performance are demonstrated in this work through the use of available materials and low cost application processes. EFOI used low refractive index fluoropolymers and low cost dipping processes for application of the material to surfaces related to light transmission of LEDs and LED products. Materials included Teflon AF, an amorphous fluorinated polymer and fluorinated acrylic monomers. The DOE SSL Roadmap sets goals for LED performance moving into the future. EFOIâ??s coating technology is a means to shift the performance curve for LEDs. This is not limited to one type of LED, but is relevant across LED technologies. The metal halide work included the use of sol-gel solutions resulting in silicon dioxide and titanium dioxide coatings on the quartz substrates of the metal halide arc tubes. The coatings were applied using low cost dipping processes.

Buelow, Roger; Jenson, Chris; Kazenski, Keith

2013-03-21T23:59:59.000Z

387

DOE Solar Decathlon: News Blog » SCI-Arc/Caltech  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

SCI-Arc/Caltech SCI-Arc/Caltech Below you will find Solar Decathlon news from the SCI-Arc/Caltech archive, sorted by date. CHIP House Takes Design to Different Heights (Literally) Friday, May 13, 2011 By April Saylor Editor's Note: This entry has been cross-posted from DOE's Energy Blog. In honor of the U.S. Department of Energy Solar Decathlon-which challenges 20 collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive-we are profiling each of the 20 teams participating in the competition. The students from the Southern California Institute of Architecture and California Institute of Technology, otherwise known as the SCI-Arc/Caltech team, have teamed up to take an interesting approach to the design of their

388

Capabilities of the ARCS Instrument - ORNL Neutron Sciences  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Capabilities of the ARCS Instrument Capabilities of the ARCS Instrument ARCS Overview The wide angular-range chopper spectrometer ARCS at the Spallation Neutron Source (SNS) is optimized to provide a high neutron flux at the sample position with a large solid angle of detector coverage. The instrument incorporates modern neutron instrumentation, such as an elliptically focused neutron guide, high speed magnetic bearing choppers, and a massive array of 3He linear position sensitive detectors. Novel features of the spectrometer include the use of a large gate valve between the sample and detector vacuum chambers and the placement of the detectors within the vacuum, both of which provide a window-free final flight path to minimize background scattering while allowing rapid changing of the sample and

389

Arc Vault Significantly Reduces Electrical Hazards | GE Global...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The transfer of arc flash energy is accomplished by triggering an ablative plasma gun to generate a 3-phase fault within a safe containment. The plasma gun operates in few...

390

Measurement of total ion current from vacuum arc plasmasources  

SciTech Connect (OSTI)

The total ion current generated by a vacuum arc plasma source was measured. The discharge system investigated allowed ion collection from the arc plasma streaming through a hemispherical mesh anode with geometric transparency of 72 percent. A range of different cathode materials was investigated, and the arc current was varied over the range 50-500 A. We find that the normalized ion current (Iion/Iarc) depends on the cathode material, with values in the range from 5 percent to 19 percent and generally greater for elements of low cohesive energy. The application of a strong axial magnetic field in the cathode and arc region leads to increased normalized ion current, but only by virtue of enhanced ion charge states formed in a strong magnetic field.

Oks, Efim M.; Savkin, Konstantin P.; Yushkov, Georgiu Yu.; Nikolaev, Alexey G.; Anders, A.; Brown, Ian G.

2005-07-01T23:59:59.000Z

391

Micro-arc oxidation coatings on Mg-Li alloys  

Science Journals Connector (OSTI)

Micro-arc oxidation (MAO) method was used for the...in-situ fabricated on the Mg-Li alloy. The morphology feature, phase composition, and corrosion-resistance of the formed ceramic coatings were studied by SEM, X...

Yongjun Xu; Kang Li; Zhongping Yao; Zhaohua Jiang; Milin Zhang

2009-04-01T23:59:59.000Z

392

Type B Accident Investigation of the Arc Flash at Brookhaven...  

Broader source: Energy.gov (indexed) [DOE]

B Accident Investigation of the Arc Flash at Brookhaven National Laboratory, April 14, 2006 More Documents & Publications DOE-HDBK-1092-1998 DOE-HDBK-1092-2004 DOE-HDBK-1092-2013...

393

Problems of physical modeling of electric-arc discharges  

Science Journals Connector (OSTI)

Special features of physical modeling of high-current arc discharges are considered. It is shown that the employment of dimensionless criterial expressions makes it possible to establish only approximate simil...

O. I. Yas'ko

394

Electric Parameters of the D.C. Carbon Arc  

Science Journals Connector (OSTI)

The basic electric parameters of an arc discharge are the current strength (i) and the voltage drop across the gap (V). Both quantities can be measured without difficulty. In general, a relationship between V and...

P. W. J. M. Boumans

1966-01-01T23:59:59.000Z

395

Effect of electric arc discharge on hypersonic blunt body drag  

Science Journals Connector (OSTI)

Experimental results on the effect of energy deposition using an electric arc discharge, upstream of a 60°...half angle blunt cone configuration in a hypersonic flow is reported.Investigations involving drag meas...

K. Satheesh; G. Jagadeesh

2009-01-01T23:59:59.000Z

396

Velocity of the electric arc in a plasmatron discharge chamber  

Science Journals Connector (OSTI)

An experimental investigation of the velocity of a high-current arc with air injection in the discharge chamber of a coaxial sectioned plasmatron is described. The experiments showed that the velocity of the c...

A. S. Shaboltas

1969-09-01T23:59:59.000Z

397

A forevacuum pulse arc-discharge-based plasma electron source  

Science Journals Connector (OSTI)

An arc-discharge-based electron source is described, which is designed for forming a pulsed wideaperture electron beam in the forevacuum pressure range (4...2 in the submillisecond range of pulse durations. The c...

A. V. Kazakov; V. A. Burdovitsin; A. V. Medovnik…

2013-11-01T23:59:59.000Z

398

Preliminary Investigations of Joining Technologies for Attaching Refractory Metals to Ni-Based Superalloys  

SciTech Connect (OSTI)

In this study, a range of joining technologies has been investigated for creating attachments between refractory metal and Ni-based superalloys. Refractory materials of interest include Mo-47%Re, T-111, and Ta-10%W. The Ni-based superalloys include Hastelloy X and MarM 247. During joining with conventional processes, these materials have potential for a range of solidification and intermetallic formation-related defects. For this study, three non-conventional joining technologies were evaluated. These included inertia welding, electro-spark deposition (ESD) welding, and magnetic pulse welding (MPW). The developed inertia welding practice closely paralleled that typically used for the refractory metals alloys. Metallographic investigations showed that forging during inertia welding occurred predominantly on the refractory metal side. It was also noted that at least some degree of forging on the Ni-based superalloy side of the joint was necessary to achieve consistent bonding. Both refractory metals were readily weldable to the Hastelloy X material. When bonding to the MarM 247, results were inconsistent. This was related to the higher forging temperatures of the MarM 247, and subsequent reduced deformation on that material during welding. ESD trials using a Hastelloy X filler were successful for all material combinations. ESD places down very thin (5- to 10-{mu}m) layers per pass, and interactions between the substrates and the fill were limited (at most) to that layer. For the refractory metals, the fill only appeared to wet the surface, with minimal dilution effects. Microstructures of the deposits showed high weld metal integrity with maximum porosity on the order of a few percent. Some limited success was also obtained with MPW. In these trials, only the T-111 tubes were used. Joints were possible for the T-111 tube to the Hastelloy X bar stock, but the stiffness of the tube (resisting collapse) necessitated the use of very high power levels. These power levels resulted in damage to the equipment (concentrator) during welding. It is of note that the joint made showed the typical wavy bond microstructure associated with magnetic pulse/explosion bond joints. Joints were not possible between the T-111 tube and the MarM 247 bar stock. In this case, the MarM 247 shattered before sufficient impact forces could be developed for bonding.

Gould, Jerry E. [Edison Welding Institute, 1250 Arthur E. Adams Drive, Columbus, OH 43221 (United States); Ritzert, Frank J. [NASA Glenn Research Center, 21000 Brookpark Road, Mail Stop 49-1, Cleveland, OH 44135 (United States); Loewenthal, William S. [Ohio Aerospace Institute, 21000 Brookpark Road, Mail Stop 49-1, Cleveland, OH 44135 (United States)

2006-01-20T23:59:59.000Z

399

Insights Gained from Ultrasonic Testing of Piping Welds Subjected to the Mechanical Stress Improvement Process  

SciTech Connect (OSTI)

Pacific Northwest National Laboratory (PNNL) is assisting the United States Nuclear Regulatory Commission (NRC) in developing a position on the management of primary water stress corrosion cracking (PWSCC) in leak-before-break piping systems. Part of this involves determining whether inspections alone, or inspections plus mitigation, are needed. This work addresses the reliability of ultrasonic testing (UT) of cracks that have been mitigated by the mechanical stress improvement process (MSIP). The MSIP has been approved by the NRC (NUREG-0313) since 1986 and modifies residual stresses remaining after welding with compressive, or neutral, stresses near the inner diameter surface of the pipe. This compressive stress is thought to arrest existing cracks and inhibit new crack formation. To evaluate the effectiveness of the MSIP and the reliability of ultrasonic inspections, flaws were evaluated both before and after MSIP application. An initial investigation was based on data acquired from cracked areas in 325-mm-diameter piping at the Ignalina Nuclear Power Plant (INPP) in Lithuania. In a follow-on exercise, PNNL acquired and evaluated similar UT data from a dissimilar metal weld (DMW) specimen containing implanted thermal fatigue cracks. The DMW specimen is a carbon steel nozzle-to-safe end-to-stainless steel pipe section that simulates a pressurizer surge nozzle. The flaws were implanted in the nozzle-to-safe end Alloy 82/182 butter region. Results are presented on the effects of MSIP on specimen surfaces, and on UT flaw responses.

Anderson, Michael T.; Cinson, Anthony D.; Crawford, Susan L.; Diaz, Aaron A.; Moran, Traci L.

2010-12-01T23:59:59.000Z

400

Main conclusions of the PISC action on safe-end welds  

SciTech Connect (OSTI)

Action 3 was initiated in 1986, in the framework of the PISC 3 program, to evaluate the actual NDE capability for the structural integrity assessment of safe-ends in power plants. Applying the methodology developed in PISC 1 and PISC 2, Round-Robin Trials (RRT) were organized on the basis of test assemblies representative of BWR and PWR designs, with the objective of identifying effective examination methods, particularly for in-service inspection, and of informing subsequently Codes and Standards organizations of the outcomes. The features of the assemblies allow to evaluate the inspection performances on reactor pressure vessel safe-end welds, as well as on PWR steam Generator and source line dissimilar metal welds. The attention of the reader is drawn however on the fact that, when conclusions on the NDT capability in industrial conditions are drawn from this exercise, the validity of the comparison must be carefully verified. The following reviews briefly the organization and integrates the main outcomes of PISC Action 3. Further details can be found in the dedicated PISC reports.

Dombret, P. [AIB-Vincotte, Brussels (Belgium); Crutzen, S. [Commission of the European Communities, Ispra (Italy)

1994-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Effects of Post-Weld Heat Treatment on the Mechanical Properties of Similar- and Dissimilar-Alloy Friction Stir Welded Blanks  

SciTech Connect (OSTI)

Friction stir welding is a solid state joining process with relatively low welding temperatures. Nevertheless, the mechanical properties of friction stir welded blanks are degraded after welding. Indeed, both strength and ductility of the welds are decreased after welding. Often, the resulting friction stir welded blanks need to be formed to their final structural shape. Therefore, the formability of friction stir welded blanks is of primary importance in the manufacturing of structural parts. This paper studies how the mechanical properties and particularly formability of friction stir welded blanks can be improved by applying a post weld heat treatment. Two aluminum alloys from 2000 and 7000 series, namely 2024-T3 and 7075-T6, are selected for the study. The sheet thickness of both materials is 2,0 mm. The selected alloys are welded in three configurations: 2024-T3 and 2024-T3, 7075-T6 and 7075-T6, and 2024-T3 and 7075-T6. The resulting welds are naturally aged for a few months. Three sets of standard dog bone shape tensile test specimens are then machined from the welds. The first set of the specimens is tested without any heat treatment. The second set of the specimens is solution heat treated and quenched before testing. The third set of the specimens is solution heat treated, quenched, and naturally aged for a week before testing. The mechanical properties of the three different sets of specimens are compared with each other. It is shown that careful selection of post weld heat-treatment can greatly improve the formability of friction stir welded blanks.

Zadpoor, Amir Abbas [Materials Innovation Institute (M2i), Mekelweg 2, Delft 2628CD (Netherlands); Faculty of Aerospace Engineering, Delft University of Technology (TU Delft), Mekelweg 2, Delft 2629HS (Netherlands); Sinke, Jos [Faculty of Aerospace Engineering, Delft University of Technology (TU Delft), Mekelweg 2, Delft 2629HS (Netherlands)

2011-01-17T23:59:59.000Z

402

Synthesis of silicon nanotubes by DC arc plasma method  

SciTech Connect (OSTI)

Plasma synthesis is a novel technique of synthesis of nanomaterials as they provide high rate of production and promote metastable reactions. Very thin walled silicon nanotubes were synthesized in a DC direct arc thermal plasma reactor. The effect of parameters of synthesis i.e. arc current and presence of hydrogen on the morphology of Si nanoparticles is reported. Silicon nanotubes were characterized by Transmission Electron Microscopy (TEM), Local Energy Dispersive X-ray analysis (EDAX), and Scanning Tunneling Microscopy (STM).

Tank, C. M.; Bhoraskar, S. V.; Mathe, V. L. [Department of Physics, University of Pune, Pune-7, Maharashtra (India)

2012-06-05T23:59:59.000Z

403

JOURNAL DE PPHYSIQUE THEORY OF =LOW CATHODEINATMOSPHERIC ARC INNOBLE GAS  

E-Print Network [OSTI]

. S. S. R. 1. The hollow arc discharge i n cylindrical hollow cathode (IiC) with s l i g h t l yJOURNAL DE PPHYSIQUE THEORY OF =LOW CATHODEINATMOSPHERIC ARC INNOBLE GAS F.G. Baksht, A.B. Rybakov. 4-22742~-j,2x$-.@+.j# .Ya4z(5) 4. he pre-electr*e ionization ~ w e r(L df 9 e L 4 - ~ = d ; ) must

Boyer, Edmond

404

Experimental Study on Gasoline Reforming Assisted by Nonthermal Arc Discharge  

Science Journals Connector (OSTI)

The gasoline conversion efficiency decreased when the electric discharge regime was changing from continuous to gliding arc and from gliding to streamer. ... Compared with catalytic reformers, plasma devices have so far lower performances, which is explained by the early stage of research on nonthermal plasma reforming and the need of an external energy input (electricity). ... and design of the plasma reactor, composed of two gliding arc discharges in series, were detailed. ...

Jean-Damien Rollier; José Gonzalez-Aguilar; Guillaume Petitpas; Adeline Darmon; Laurent Fulcheri; Rudolf Metkemeijer

2007-12-06T23:59:59.000Z

405

Accurate modelling of anisotropic effects in austenitic stainless steel welds  

SciTech Connect (OSTI)

The ultrasonic inspection of austenitic steel welds is challenging due to the formation of highly anisotropic and heterogeneous structures post-welding. This is due to the intrinsic crystallographic structure of austenitic steel, driving the formation of dendritic grain structures on cooling. The anisotropy is manifested as both a ‘steering’ of the ultrasonic beam and the back-scatter of energy due to the macroscopic granular structure of the weld. However, the quantitative effects and relative impacts of these phenomena are not well-understood. A semi-analytical simulation framework has been developed to allow the study of anisotropic effects in austenitic stainless steel welds. Frequency-dependent scatterers are allocated to a weld-region to approximate the coarse grain-structures observed within austenitic welds and imaged using a simulated array. The simulated A-scans are compared against an equivalent experimental setup demonstrating excellent agreement of the Signal to Noise (S/N) ratio. Comparison of images of the simulated and experimental data generated using the Total Focusing Method (TFM) indicate a prominent layered effect in the simulated data. A superior grain allocation routine is required to improve upon this.

Nowers, O. D.; Duxbury, D. J. [NDE Research, Support and Development, Rolls-Royce Marine, Derby, PO BOX 2000, DE21 7XX (United Kingdom); Drinkwater, B. W. [Department of Mechanical Engineering, University Walk, University of Bristol, Bristol BS8 1TR (United Kingdom)

2014-02-18T23:59:59.000Z

406

Lightning Induced Arcing an LDRD Report  

SciTech Connect (OSTI)

The purpose of this research was to develop a science-based understanding of the early-time behavior of electric surface arcing in air at atmospheric pressure. As a first step towards accomplishing this, we used a kinetic approach to model an electron swarm as it evolved in a neutral gas under the influence of an applied electric field. A computer code was written in which pseudo-particles, each representing some number of electrons, were accelerated by an electric field. The electric field due to the charged particles was calculated efficiently using a tree algorithm. Collision of the electrons with the background gas led to the creation of new particles through the processes of ionization and photoionization. These processes were accounted for using measured cross-section data and Monte Carlo methods. A dielectric half-space was modeled by imaging the charges in its surface. Secondary electron emission from the surface, resulting in surface charging, was also calculated. Simulation results show the characteristics of a streamer in three dimensions. A numerical instability was encountered before the streamer matured to form branching.

JORGENSON,ROY E.; WARNE,LARRY K.; KUNHARDT,ERICH E.

2000-12-01T23:59:59.000Z

407

Measurements of the total ion flux from vacuum arc cathodespots  

SciTech Connect (OSTI)

The ion flux from vacuum arc cathode spots was measured in two vacuum arc systems. The first was a vacuum arc ion source which was modified allowing us to collect ions from arc plasma streaming through an anode mesh. The second discharge system essentially consisted of a cathode placed near the center of a spherically shaped mesh anode. In both systems, the ion current streaming through the mesh was measured by a biased collector. The mesh anodes had geometric transmittances of 60 percent and 72 percent, respectively, which were taken into account as correction factors. The ion current from different cathode materials was measured for 50-500 A of arc current. The ion current normalized by the arc current was found to depend on the cathode material, with values in the range from 5 percent to 19 percent. The normalized ion current is generally greater for elements of low cohesive energy. The ion erosion rates were determined from values of ion current and ion charge states, which were previously measured in the same ion source. The absolute ion erosion rates range from 16-173 mu g/C.

Anders, Andre; Oks, Efim M.; Yushkov, Georgy Yu; Savkin,Konstantin P.; Brown, Ian G.; Nikolaev, Alexey G.

2005-05-25T23:59:59.000Z

408

High-speed EDM milling with moving electric arcs  

Science Journals Connector (OSTI)

A novel high-speed electrical discharge machining (EDM) milling method using moving electric arcs has been proposed in this study. We connected a copper electrode rotating rapidly around its axis and a work piece to a DC power supply to generate a moving electric arc. To ensure high relative speed of any point on the electrode with respect to the work piece, the electrode was shaped like a pipe. It was observed that the electric arcs move rapidly within the discharge gap due to the revolution of the tool electrode, removing the materials on the electrode along the track of the arc roots. To explore the characteristics of machining with moving electric arcs, an EDM milling apparatus was devised. Two planes with approximately the same roughness were machined separately by this equipment and a traditional EDM machine for comparison. It was found that a much higher material removal rate can be easily achieved by EDM milling with moving electric arcs. In the meanwhile, wear of the tool electrode in this new method is negligible, which is greatly favorable for machining accuracy. The microstructures of these surfaces were also investigated for further information.

Fuzhu Han; Yongxain Wang; Ming Zhou

2009-01-01T23:59:59.000Z

409

Directed light fabrication of refractory metals  

SciTech Connect (OSTI)

Directed Light Fabrication (DLF) is a metal, rapid fabrication process that fuses metal powders to full density into a solid replica of a computer modeled component. It has been shown feasible for forming nearly any metal and also intermetallics to near net shape with a single process. DLF of refractory pure metals is feasible, bypassing the extensive series of conventional processing steps used for processing these high melting point materials. Tungsten, tantalum, and rhenium were processed and show a continuous resolidified microstructure. Porosity was a problem for the tantalum and rhenium powders produced by chemical reduction processes but not for the tungsten powder spherodized in a plasma arc. Chemical analysis of powder compared to the DLF deposit showed reductions in carbon, oxygen and hydrogen, indicating that process parameters may also be optimized for evolution of residual gases in the deposits.

Lewis, G.K.; Thoma, D.J.; Nemec, R.B.; Milewski, J.O. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

1997-11-01T23:59:59.000Z

410

Metal inks  

DOE Patents [OSTI]

Self-reducing metal inks and systems and methods for producing and using the same are disclosed. In an exemplary embodiment, a method may comprise selecting metal-organic (MO) precursor, selecting a reducing agent, and dissolving the MO precursor and the reducing agent in an organic solvent to produce a metal ink that remains in a liquid phase at room temperature. Metal inks, including self-reducing and fire-through metal inks, are also disclosed, as are various applications of the metal inks.

Ginley, David S; Curtis, Calvin J; Miedaner, Alex; van Hest, Marinus Franciscus Antonius Maria; Kaydanova, Tatiana

2014-02-04T23:59:59.000Z

411

Seminar on dissimilar welds in fossil-fired boilers: proceedings. [Often ferritic and austenitic steels  

SciTech Connect (OSTI)

Failure of dissimilar metal welds (DMW) in superheater and reheater sections is a major cause of forced outage of boilers. Research and development has been in progress at several organizations throughout the world including a major project, RP 1874, sponsored by EPRI. As a result of these efforts the causes of DMW failures are now better known than before. Several viable remedies have been identified. The effects of plant operational variables on damage to the DMWs have been quantified. Methods for assessing the condition of DMWs in the field have been developed. A seminar was organized for the purpose of reviewing and consolidating all the information available relating to failure causes and remedies for the DMW failure problems. The proceedings from the seminar are presented in this report. The papers have been entered individually into EDB and ERA. (LTN)

Viswanathan, R.; Roberts, D.A. (eds.)

1985-07-01T23:59:59.000Z

412

Steam generator for liquid metal fast breeder reactor  

DOE Patents [OSTI]

Improvements in the design of internal components of J-shaped steam generators for liquid metal fast breeder reactors. Complex design improvements have been made to the internals of J-shaped steam generators which improvements are intended to reduce tube vibration, tube jamming, flow problems in the upper portion of the steam generator, manufacturing complexities in tube spacer attachments, thermal stripping potentials and difficulties in the weld fabrication of certain components.

Gillett, James E. (Greensburg, PA); Garner, Daniel C. (Murrysville, PA); Wineman, Arthur L. (Greensburg, PA); Robey, Robert M. (North Huntingdon, PA)

1985-01-01T23:59:59.000Z

413

Metal Oxides  

Science Journals Connector (OSTI)

Metal oxides are the class of materials having the widest application in gas sensors. This chapter presents information related to the application of various metal oxides in gas sensors designed on different p...

Ghenadii Korotcenkov

2013-01-01T23:59:59.000Z

414

Ultrasonic inspection of austenitic stainless steel welds with artificially produced stress corrosion cracks  

SciTech Connect (OSTI)

Austenitic stainless steel welds and nickel alloy welds, which are widely used in nuclear power plants, present major challenges for ultrasonic inspection due to the grain structure in the weld. Large grains in combination with the elastic anisotropy of the material lead to increased scattering and affect sound wave propagation in the weld. This results in a reduced signal-to-noise ratio, and complicates the interpretation of signals and the localization of defects. Mechanized ultrasonic inspection was applied to study austenitic stainless steel test blocks with different types of flaws, including inter-granular stress corrosion cracks (IGSCC). The results show that cracks located in the heat affected zone of the weld are easily detected when inspection from both sides of the weld is possible. In cases of limited accessibility, when ultrasonic inspection can be carried out only from one side of a weld, it may be difficult to distinguish between signals from scattering in the weld and signals from cracks.

Dugan, Sandra; Wagner, Sabine [Materials Testing Institute University of Stuttgart (MPA), Pfaffenwaldring 32, 70569 Stuttgart (Germany)

2014-02-18T23:59:59.000Z

415

Applications and case studies of laser hybrid welding in the automotive industry  

Science Journals Connector (OSTI)

In joining technology, the high welding speed on the one and the good gap bridging ability on the other hand play a significant part. It is no doubt that the laser beam welding and the GMA welding have been established in the welding technology for very long, and that both processes allow a wide field of application in the joining technology. New possibilities and synergetic effects, however, are based on the combination of both processes. The laser radiation causes a very narrow thermally affected zone with a high ratio between welding depth and seam width. In the case of the laser welding process, the gap bridging ability is very low due to the small focus diameter, however very high welding speeds can be achieved. The GMA or Tandem welding process features a significantly lower energy density has a larger focused spot on the material surface and is characterised by its good gap bridging ability.

H. Staufer

2010-01-01T23:59:59.000Z

416

E-Print Network 3.0 - adaptive robotic welding Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

welding Page: << < 1 2 3 4 5 > >> 1 ORIGINAL ARTICLE Development of a mobile welding robot for double-hull structures Summary: , the CPU board recalculates the path of the...

417

Vehicle Technologies Office Merit Review 2014: On-Line Weld NDE...  

Broader source: Energy.gov (indexed) [DOE]

On-Line Weld NDE with IR Thermography Vehicle Technologies Office Merit Review 2014: On-Line Weld NDE with IR Thermography Presentation given by Oak Ridge National Laboratory at...

418

Silicone metalization  

DOE Patents [OSTI]

A system for providing metal features on silicone comprising providing a silicone layer on a matrix and providing a metal layer on the silicone layer. An electronic apparatus can be produced by the system. The electronic apparatus comprises a silicone body and metal features on the silicone body that provide an electronic device.

Maghribi, Mariam N. (Livermore, CA); Krulevitch, Peter (Pleasanton, CA); Hamilton, Julie (Tracy, CA)

2006-12-05T23:59:59.000Z

419

Three-dimensional Ion Distribution in a Filtered Vacuum Arc Discharge  

SciTech Connect (OSTI)

Three-dimensional measurements of the ion flux along the filter of a magnetically filtered d-c vacuum arc are presented. The device includes a metallic plasma-generating chamber with cooper electrodes coupled to a substrate chamber through a quarter-torus magnetic filter. The filtering magnetic field was high enough to magnetize the electrons but not the ions. The ion current distribution was studied using a multi-element Cu probes, placed at three different positions along the filter. The ion saturation current of each probe was measured by biasing the probe at -70V with respect the grounded anode. Preliminary results of the three dimensional ion flux distribution and the floating potential of the plasma as functions of the bias filter voltage and magnetic field intensity are reported.

Kelly, H.; Marquez, A.; Pirrera, M. [Instituto de Fisica del Plasma, CONICET-Dpto. de Fisica, FCEN, UBA, Ciudad Universitaria Pab. 1 (1428EHA) Ciudad de Buenos Aires (Argentina)

2006-12-04T23:59:59.000Z

420

Mechanical Characteristics of Submerged Arc Weldment in API Gas Pipeline Steel of Grade X65  

SciTech Connect (OSTI)

The mechanical properties of submerged arc weldment (SAW) in gas transportation pipeline steel of grade API X65 (65 ksi yield strength) were investigated. This steel is produced by thermo mechanical control rolled (TMC), and is largely used in Iran gas piping systems and networks. The results from laboratory study on three different regions; i.e. base metal (BM), fusion zone (FZ) and heat affected zone (HAZ) were used to compare weldment mechanical characteristics with those specified by API 5L (revision 2004) standard code. Different laboratory experiments were conducted on test specimens taken from 48 inch outside diameter and 14.3 mm wall thickness gas pipeline. The test results showed a gradient of microstructure and Vickers hardness data from the centerline of FZ towards the unaffected MB. Similarly, lower Charpy absorbed energy (compared to BM) was observed in the FZ impact specimens. Despite this, the API specifications were fulfilled in three tested zones, ensuring pipeline structural integrity under working conditions.

Hashemi, S. H. [Department of Mechanical Engineering, University of Birjand, POBOX 97175-376, Birjand (Iran, Islamic Republic of); Mohammadyani, D. [Materials and Energy Research Center (MERC) POBOX 14155-4777, Tehran (Iran, Islamic Republic of)

2011-01-17T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Integrated thermal-microstructure model to predict the property gradients in resistance spot steel welds  

SciTech Connect (OSTI)

An integrated model approach was proposed for relating resistance welding parameters to weldment properties. An existing microstructure model was used to determine the microstructural and property gradients in resistance spot welds of plain carbon steel. The effect of these gradients on the weld integrity was evaluated with finite element analysis. Further modifications to this integrated thermal-microstructure model are discussed.

Babu, S.S.; Riemer, B.W.; Santella, M.L. [Oak Ridge National Lab., TN (United States); Feng, Z. [Edison Welding Inst., Columbus, OH (United States)

1998-11-01T23:59:59.000Z

422

Dynamic voltage-current characteristics for a water jet plasma arc  

SciTech Connect (OSTI)

A virtual instrument technology is used to measure arc current, arc voltage, dynamic V-I characteristics, and nonlinear conductance for a cone-shaped water jet plasma arc under ac voltage. Experimental results show that ac arc discharge mainly happens in water vapor evaporated from water when heated. However, due to water's cooling effect and its conductance, arc conductance, reignition voltage, extinguish voltage, and current zero time are very different from those for ac arc discharge in gas work fluid. These can be valuable to further studies on mechanism and characteristics of plasma ac discharge in water, and even in gas work fluid.

Yang Jiaxiang; Lan Sheng; Xu Zuoming [College of Electrical and Electronic Engineering, Harbin University of Science and Technology, Harbin, Heilongjiang 150040 (China)

2008-05-05T23:59:59.000Z

423

Advanced RenewableEnergy Company ARC Energy | Open Energy Information  

Open Energy Info (EERE)

Advanced RenewableEnergy Company ARC Energy Advanced RenewableEnergy Company ARC Energy Jump to: navigation, search Name Advanced RenewableEnergy Company (ARC Energy) Place Nashua, New Hampshire Product New Hampshire-based stealth mode LED substrate manufacture equipment provider which aims to lower the cost of LEDs. Coordinates 42.758365°, -71.464209° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":42.758365,"lon":-71.464209,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

424

ArcSafe® with Pulsed Arrested Spark Discharge  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ArcSafe® ArcSafe® with Pulsed Arrested Spark Discharge  2007 R&D 100 Award Entry Form ArcSafe® with Pulsed Arrested Spark Discharge  Joint Submitters Submitting Organization Sandia National Laboratories PO Box 5800, MS 1181 Albuquerque, NM 87185-1181 USA Larry Schneider Phone: (505) 845-7135 Fax: (505) 845-7685 Email: lxschne@sandia.gov AFFIRMATION: I affirm that all information submitted as a part of, or supplemental to, this entry is a fair and accurate represen- tation of this product. (Signature)______________________________________ Astronics-Advanced Electronic Systems, Inc. 9845 Willows Rd NE City: Redmond State: WA Zip/Postal: 98052-2540 USA Contact Name: Michael Ballas, Program Manager Phone: (425) 895-4304 Fax: (425)702.4930 Email: michael.ballas@astronics.com

425

A Miocene Island-Arc Volcanic Seamount- The Takashibiyama Formation,  

Open Energy Info (EERE)

Island-Arc Volcanic Seamount- The Takashibiyama Formation, Island-Arc Volcanic Seamount- The Takashibiyama Formation, Shimane Peninsula, Sw Japan Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Miocene Island-Arc Volcanic Seamount- The Takashibiyama Formation, Shimane Peninsula, Sw Japan Details Activities (0) Areas (0) Regions (0) Abstract: The Miocene volcanic complex of the Takashibiyama Formation consists largely of subalkali, subaqueous basalt to andesite lavas and andesite to dacite subaqueous volcaniclastic flow deposits. Most of subaqueous lavas are moderately to intensely brecciated with rugged rough surfaces and ramp structures similar to subaerial block lava. Volcaniclastic flow deposits commonly include basalt to andesite lava fragments and/or pyroclastic materials, and are similar in internal

426

Measurement of total ion flux in vacuum Arc discharges  

SciTech Connect (OSTI)

A vacuum arc ion source was modified allowing us to collections from arc plasma streaming through an anode mesh. The mesh had ageometric transmittance of 60 percent, which was taken into account as acorrection factor. The ion current from twenty-two cathode materials wasmeasured at an arc current of 100 A. The ion current normalized by thearc current was found to depend on the cathode material, with valuesinthe range from 5 percent to 11 percent. The normalized ion current isgenerally greater for light elements than for heavy elements. The ionerosion rates were determined fromvalues of ion currentand ion chargestates, which were previously measured in the same experimental system.The ion erosion rates range from 12-94 mu g/C.

Anders, Andre; Oks, Efim M.; Yushkov, Georgy Yu.; Brown, Ian G.

2004-04-12T23:59:59.000Z

427

Voltage flicker prediction for two simultaneously operated ac arc furnaces  

SciTech Connect (OSTI)

An EMTP-based arc furnace model was developed for evaluation of flicker concerns associated with supplying a large integrated steel mill as they go from one to two furnace operation and as system changes are implemented that will affect the short circuit capacity at the 230 kV power supply substation. The model includes a dynamic arc representation which is designed to be characteristic of the initial portions of the melt cycle when the arc characteristics are the most variable (worst flicker conditions). The flicker calculations are verified using previous measurements with one furnace operation. Flicker simulations were then performed to evaluate a variety of different possible system strengths with both one and two furnaces in operation. The primary flicker measure used for this study is the unweighted rms value of the fluctuation envelope, expressed as a percentage of the rms line-to-ground voltage magnitude.

Tang, L. [ABB Power T and D Co., Inc., Raleigh, NC (United States)] [ABB Power T and D Co., Inc., Raleigh, NC (United States); Kolluri, S. [Entergy Services, New Orleans, LA (United States)] [Entergy Services, New Orleans, LA (United States); McGranaghan, M.F. [Electrotek Concepts, Inc., Knoxville, TN (United States)] [Electrotek Concepts, Inc., Knoxville, TN (United States)

1997-04-01T23:59:59.000Z

428

PNNL 331 Building Arc Flash Team Investigation Report  

SciTech Connect (OSTI)

On Friday, April 21, 2006, a PNNL electrician was performing repair of an electrical system for the 331 Building chilled water pump (CHWP) No.2, when an electrical arc flash occurred inside a 480V combination motor starter. The electrician was taken to the on-site medical provider for evaluation and was released for return to work without restriction. The electrician was not shocked, but did receive a minor, superficial (first degree) burn on the left wrist. This report, the result of a thorough review by the 331 Building Arc Flash Assessment Team, provides an in-depth look at the steps leading up to the arc-flash and recommendations and opportunities for improvement.

Deichman, Mark L.; Drewrey, John C.; Hodges, Hurtis; Madson, Vernon J.; Minton, Allen L.; Montgomery, Daniel M.; Olson, Marvin E.; Rojas, Pedro H.; Sanan, Sanjay K.; Sharp, Reed D.; Sparks, Bobby R.; Swearingen, Gary L.

2006-06-06T23:59:59.000Z

429

Multipass Arc Lattice Design for Recirculating Linac Muon Accelerators  

SciTech Connect (OSTI)

Recirculating linear accelerators (RLA) are the most likely means to achieve rapid acceleration of short-lived muons to multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. A drawback of this scheme is that a separate return arc is required for each passage of the muons through the linac. In the work described here, a novel arc optics based on a Non-Scaling Fixed Field Alternating Gradient (NSFFAG) lattice is developed, which would provide sufficient momentum acceptance to allow multiple passes (two or more consecutive energies) to be transported in one string of magnets. An RLA with significantly fewer arcs will reduce the cost. We will develop the optics and technical requirements to allow the maximum number of passes by using an adjustable path length to accurately control the returned beam to synchronize with the linac RF phase.

G.M. Wang, R.P. Johnson, S.A. Bogacz, D. Trbojevic

2009-05-01T23:59:59.000Z

430

Use of Aria to simulate laser weld pool dynamics for neutron generator production.  

SciTech Connect (OSTI)

This report documents the results for the FY07 ASC Integrated Codes Level 2 Milestone number 2354. The description for this milestone is, 'Demonstrate level set free surface tracking capabilities in ARIA to simulate the dynamics of the formation and time evolution of a weld pool in laser welding applications for neutron generator production'. The specialized boundary conditions and material properties for the laser welding application were implemented and verified by comparison with existing, two-dimensional applications. Analyses of stationary spot welds and traveling line welds were performed and the accuracy of the three-dimensional (3D) level set algorithm is assessed by comparison with 3D moving mesh calculations.

Noble, David R.; Notz, Patrick K.; Martinez, Mario J.; Kraynik, Andrew Michael

2007-09-01T23:59:59.000Z

431

3013 DE INNER CONTAINER CLOSURE WELD CORROSION EVALUATION  

SciTech Connect (OSTI)

Destructive evaluation (DE) of 3013 containers is one part of the U. S. Department of Energy Integrated Surveillance Program. During standard DE of 3013 containers, visual examinations for pitting and stress corrosion cracking (SCC) are performed on the accessible surfaces of the outer, inner, and convenience containers, which make up the 3013 container. As a result of 3013 DE additional analysis, the area near the inner container closure weld has been identified as being a region of increased corrosion susceptibility, which may provide a pathway for corrosive gases to the outer container. This area has a higher residual stress, an altered microstructure, and less corrosion resistant weld oxides as a result of the welding process as well as a lower temperature than other areas of the container, which may increase the absorption of moisture on the surface. The deposition of moisture in this stressed region could lead to pitting and stress corrosion cracking. During FY2013, the inner container closure weld area was more closely evaluated on several archived samples from DE containers. These containers included FY09 DE2, FY12 DE4, FY12 DE6 and FY12 DE7 and the Hanford High Moisture Container. The additional examinations included visual observations with a stereomicroscope, scanning electron microscopy along with energy dispersive spectroscopy for chemical analysis, and serial metallography of the sidewall and lid that are part of the inner container closure weld region. Pitting was observed in all the samples taken from the closure weld regions of the examined inner containers. This pitting was generally less 20 μm with most less than 5m. These pits were similar in depth to those observed in the vapor exposed surfaces of teardrops in the shelf life corrosion testing. Cracking was not observed on either the vapor-exposed surfaces of the teardrop coupons or the inner container closure weld region. Further testing is necessary to determine if the conditions in the welded inner container could support SCC during the 50 year life time for the 3013 container.

Mickalonis, J.

2013-09-30T23:59:59.000Z

432

Closed-loop focus control system for laser welding  

SciTech Connect (OSTI)

In this paper the authors describe a focus control system for Nd:YAG laser welding based on an optical sensor incorporated into the fibre delivery system to detect light generated by the process. This broadband light is separated into two wavelength bands, and simple electronic processing gives a signal proportional to focal error, as a result of chromatic aberrations in the optical delivery system. Focus control is demonstrated for bead-on-plate welds in different thicknesses of titanium alloy, aluminum alloy, mild steel and stainless steel. The control system works for both pulsed and continuous laser radiation.

Haran, F.M.; Hand, D.P.; Jones, J.D.C. [Heriot-Watt Univ., Edinburgh (United Kingdom); Peters, C. [Lumonics Ltd., Rugby (United Kingdom)

1996-12-31T23:59:59.000Z

433

An investigation of residual stress in welded joints  

E-Print Network [OSTI]

not extended beyond eight days time~ therefore the curve does not show com- plete relaxation of stress v!ith age of weld. However the figures "or the longitudinal stress compare favorably with that calculated by Houlton and iiartin (1) of 55, 000 psi... are bolted or doweled to a heavy cast iron or steel frame as shown which is of sufficient rigidity that all of the strain takes place in the specimen. The weld and the strain gage are separated sufficiently and the area between may be water cooled so II...

Moffat, William Hugh

1951-01-01T23:59:59.000Z

434

Vinyl chloride monomer and other contaminants in PVC welding fumes  

SciTech Connect (OSTI)

An investigation into the nature of fumes produced during thermal welding of plasticized PVC sheeting has been carried out with the objective of determining if the known carcinogen vinyl chloride monomer (VCM) is formed and to assess the level of exposure to the operator. The results show that the atmospheric concentrations of VCM are well below accepted occupational exposure limits. This finding is consistent with reports in the technical literature which suggest that VCM is produced during thermal degradation of PVC only at temperatures considerably higher than those encountered during plastic welding.

Williamson, J.; Kavanagh, B.

1987-05-01T23:59:59.000Z

435

Apparatus and process for ultrasonic seam welding stainless steel foils  

DOE Patents [OSTI]

An ultrasonic seam welding apparatus having a head which is rotated to form contact, preferably rolling contact, between a metallurgically inert coated surface of the head and an outside foil of a plurality of layered foils or work materials. The head is vibrated at an ultrasonic frequency, preferably along a longitudinal axis of the head. The head is constructed to transmit vibration through a contacting surface of the head into each of the layered foils. The contacting surface of the head is preferably coated with aluminum oxide to prevent the head from becoming welded to layered stainless steel foils.

Leigh, Richard W. (New York, NY)

1992-01-01T23:59:59.000Z

436

E-Print Network 3.0 - arc deposition system Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in the Asir terrane, which was active between... erosion and deposition in the back-arc basin environment (Camp, 1984). Regional metamorphism in the WBMD... volcanic arc system. J....

437

Rates of tectonic and magmatic processes in the North Cascades continental magmatic arc  

E-Print Network [OSTI]

Continental magmatic arcs are among the most dynamic. geologic systems, and documentation of the magmatic, thermal, and tectonic evolution of arcs is essential for understanding the processes of magma generation, ascent ...

Matzel, Jennifer E. Piontek, 1973-

2004-01-01T23:59:59.000Z

438

ARCS FOUNDATION GLOBAL IMPACT AWARD Global Health, Public Good and Graduate Education  

E-Print Network [OSTI]

1 ARCS FOUNDATION GLOBAL IMPACT AWARD Global Health, Public Good and Graduate Education Case the ARCS Foundation Awards Luncheon in Atlanta on November 21, 2013. Application Materials: 1) A letter

Arnold, Jonathan

439

Evolution of residual stresses in micro-arc oxidation ceramic coatings on 6061 Al alloy  

Science Journals Connector (OSTI)

Most researches on micro-arc oxidation mainly focus on the application rather than ... dimensional stability and corrosion resistance, etc. The micro-arc oxidation ceramic coatings are produced on the surfaces .....

Dejiu Shen; Jingrui Cai; Changhong Guo…

2013-11-01T23:59:59.000Z

440

Comparative analysis of methods for ion-plasma sputter deposition and micro-arc oxidation  

Science Journals Connector (OSTI)

We describe the following advantages of micro-arc oxidation (MAO) over ion-plasma sputter deposition ... of operation by personnel. These advantages make micro-arc oxidation a promising technique for metallurgica...

M. V. Gerasimov

2007-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "metal arc welding" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Numerical modeling of the interaction between an electric arc and a gas flow  

Science Journals Connector (OSTI)

The interaction between an equilibrium arc discharge and a gas (air or argon) ... The dynamics and the special features of the electric arc formation are studied for both gases. In the air the electrically conduc...

E. N. Vasil’ev; D. A. Nesterov

2013-03-01T23:59:59.000Z

442

Optimization of NH3 Decomposition by Control of Discharge Mode in a Rotating Arc  

Science Journals Connector (OSTI)

In this study, the characteristic behavior of a rotating arc was investigated. Various modes, depending on the electric power supplied, can be observed in a rotating arc. Each mode produces different discharge ch...

Dae Hoon Lee; Kwan-Tae Kim; Hee Seok Kang…

2014-01-01T23:59:59.000Z

443

Sliding electric arc discharge as a means of aircraft trajectory control  

Science Journals Connector (OSTI)

The dynamics of sliding electric arc discharge and the formation of shock waves in the stages of leader motion and the electric arc development in a supersonic air flow behind ... (bar). The air flow in the discharge

V. S. Aksenov; V. V. Golub; S. A. Gubin; V. P. Efremov…

2004-10-01T23:59:59.000Z

444

Numerical computation of electric arc with annular attachment on the cathode butt end  

Science Journals Connector (OSTI)

The results of computing a stationary arc with annular attachment on the butt end of a solid cylindrical cathode are presented. The influence of the discharge external parameters on the characteristics of arc ...

A. Zh. Zhainakov; R. M. Urusov; T. E. Urusova

2006-12-01T23:59:59.000Z

445

Growth Conditions of Double-Walled Carbon Nanotubes in Arc Discharge  

Science Journals Connector (OSTI)

Growth Conditions of Double-Walled Carbon Nanotubes in Arc Discharge ... Preparation conditions for large-scale synthesis of double-walled carbon nanotubes (DWCNTs) by using electric arc discharge were examined. ...

Yahachi Saito; Takanori Nakahira; Sashiro Uemura

2003-01-04T23:59:59.000Z

446

Mechanism of current redistribution between jets in a double-jet electric arc  

Science Journals Connector (OSTI)

Characteristics of a double-jet electric arc have been determined by numerical simulation of ... plasma electrodes, along which the character of arc discharge changes from self-sustained to non-self-...

E. B. Kulumbaev; T. B. Nikulicheva

2013-01-01T23:59:59.000Z

447

Parameters of free-burning arc discharge plasma in air with silver-based electrodes  

Science Journals Connector (OSTI)

We have used optical spectroscopy to study the radial temperature profiles for an electric arc plasma between silver electrodes and electrodes made ... . We established that the parameters of the arc discharge pl...

I. L. Babich; A. N. Veklich; L. A. Kryachko…

2006-05-01T23:59:59.000Z

448

Dependence of thermal destabilization of electric-arc plasma in an air flow on discharge conditions  

Science Journals Connector (OSTI)

The effect of the conditions of electric-arc burning in an air flow on the ... processes in the development of instability in an arc-discharge column is shown.

V. N. Borisyuk; S. V. Goncharik…

1997-03-01T23:59:59.000Z

449

E-Print Network 3.0 - arc box test Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

box test Search Powered by Explorit Topic List Advanced Search Sample search results for: arc box test Page: << < 1 2 3 4 5 > >> 1 Fat arcs for implicitly defined curves Szilvia...

450

A static voltage-current characteristic for the low current DC arc  

E-Print Network [OSTI]

systems has failed to detect arcing faults numerous times with disastrous consequences. The fault leaves a charred furrow, known as the ''arc track'', through Kapton cable insulation. Tests by NASA and others have confirmed that the average circuit...

Moores, Gregory Lee

2012-06-07T23:59:59.000Z

451

E-Print Network 3.0 - arc protection class Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in a GIS: A Bidirectional Link between ArcView 2.0TM and XGobi Summary: . The XGobi remote proce- dures callable from within ArcView 2.0 can be grouped into two classes. One...

452

E-Print Network 3.0 - arc routing problem Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Search Sample search results for: arc routing problem Page: << < 1 2 3 4 5 > >> 1 GIS by ESRITM What is ArcGIS Summary: allocation) Solving complex routing problems Querying...

453

ADVANCED INTEGRATION OF MULTI-SCALE MECHANICS AND WELDING PROCESS SIMULATION IN WELD INTEGRITY ASSESSMENT  

SciTech Connect (OSTI)

The potential to save trillions of BTU’s in energy usage and billions of dollars in cost on an annual basis based on use of higher strength steel in major oil and gas transmission pipeline construction is a compelling opportunity recognized by both the US Department of Energy (DOE). The use of high-strength steels (X100) is expected to result in energy savings across the spectrum, from manufacturing the pipe to transportation and fabrication, including welding of line pipe. Elementary examples of energy savings include more the 25 trillion BTUs saved annually based on lower energy costs to produce the thinner-walled high-strength steel pipe, with the potential for the US part of the Alaskan pipeline alone saving more than 7 trillion BTU in production and much more in transportation and assembling. Annual production, maintenance and installation of just US domestic transmission pipeline is likely to save 5 to 10 times this amount based on current planned and anticipated expansions of oil and gas lines in North America. Among the most important conclusions from these studies were: • While computational weld models to predict residual stress and distortions are well-established and accurate, related microstructure models need improvement. • Fracture Initiation Transition Temperature (FITT) Master Curve properly predicts surface-cracked pipe brittle-to-ductile initiation temperature. It has value in developing Codes and Standards to better correlate full-scale behavior from either CTOD or Charpy test results with the proper temperature shifts from the FITT master curve method. • For stress-based flaw evaluation criteria, the new circumferentially cracked pipe limit-load solution in the 2007 API 1104 Appendix A approach is overly conservative by a factor of 4/?, which has additional implications. . • For strain-based design of girth weld defects, the hoop stress effect is the most significant parameter impacting CTOD-driving force and can increase the crack-driving force by a factor of 2 depending on strain-hardening, pressure level as a % of SMYS, and flaw size. • From years of experience in circumferential fracture analyses and experimentation, there has not been sufficient integration of work performed for other industries into analogous problems facing the oil and gas pipeline markets. Some very basic concepts and problems solved previously in these fields could have circumvented inconsistencies seen in the stress-based and strain-based analysis efforts. For example, in nuclear utility piping work, more detailed elastic-plastic fracture analyses were always validated in their ability to predict loads and displacements (stresses and strains). The eventual implementation of these methodologies will result in acceleration of the industry adoption of higher-strength line-pipe steels.

Wilkowski, Gery M.; Rudland, David L.; Shim, Do-Jun; Brust, Frederick W.; Babu, Sundarsanam

2008-06-30T23:59:59.000Z

454

L3 Milestone Use Computational Model to Design and Optimize Welding Conditions to Suppress Helium  

Broader source: Energy.gov (indexed) [DOE]

L3 Milestone L3 Milestone Use Computational Model to Design and Optimize Welding Conditions to Suppress Helium Cracking during Welding June 2012 Wei Zhang and Zhili Feng, ORNL Eric Willis, EPRI Background and Objectives Today, welding is widely used for repair, maintenance and upgrade of nuclear reactor components. As a critical technology to extend the service life of nuclear power plants beyond 60 years, weld technology must be further developed to meet new challenges associated with the aging of the plants, such as control and mitigation of the detrimental effects of weld residual stresses and repair of highly irradiated materials. To meet this goal, fundamental understanding of the "welding" effect is necessary for development of new and improved welding technologies.

455

Gas and RRR distribution in high purity Niobium EB welded in Ultra-High Vacuum  

SciTech Connect (OSTI)

Electron beam (EB) welding in UHV (ultra-high vacuum, 10-5 divide 10-8 mbar) is applied in the standard fabrication of high gradient niobium superconducting radio frequency (SRF) cavities of TESLA design. The quality of EB welding is critical for cavity performance. Experimental data of gas content (H2, O2, N2) and RRR (residual resistivity ratio) measurements in niobium (Nb) welding seams are presented. EB welding in UHV conditions allow to preserve low gas content (1 divide 3 wt. ppm hydrogen and 5 divide 7 ppm oxygen and nitrogen), essential for high values of RRR - 350 divide 400 units. Gas content redistribution in the electron beam welded and heat affected region take place in the welding process. Correlation between gas solubility parameters, RRR and thermal conductivity are presented. Mechanisms of gas solubility in EB welding process are discussed.

Anakhov, S.; Singer, X.; Singer, W.; Wen, H. [RSVPU, Yekaterinburg (Russian Federation); DESY, Hamburg (Germany); IEE CAS, Beijing (China)

2006-05-24T23:59:59.000Z

456

Effect of Micro Arc Oxidation Coatings on Corrosion Resistance of 6061-Al Alloy  

Science Journals Connector (OSTI)

In the present study, the corrosion behavior of micro arc oxidation (MAO) coatings deposited at two current...

Nitin P. Wasekar; A. Jyothirmayi…

2008-10-01T23:59:59.000Z

457