National Library of Energy BETA

Sample records for metal arc welding

  1. Method for controlling gas metal arc welding

    DOE Patents [OSTI]

    Smartt, Herschel B. (Idaho Falls, ID); Einerson, Carolyn J. (Idaho Falls, ID); Watkins, Arthur D. (Idaho Falls, ID)

    1989-01-01

    The heat input and mass input in a Gas Metal Arc welding process are controlled by a method that comprises calculating appropriate values for weld speed, filler wire feed rate and an expected value for the welding current by algorithmic function means, applying such values for weld speed and filler wire feed rate to the welding process, measuring the welding current, comparing the measured current to the calculated current, using said comparison to calculate corrections for the weld speed and filler wire feed rate, and applying corrections.

  2. Method for controlling gas metal arc welding

    DOE Patents [OSTI]

    Smartt, H.B.; Einerson, C.J.; Watkins, A.D.

    1987-08-10

    The heat input and mass input in a Gas Metal Arc welding process are controlled by a method that comprises calculating appropriate values for weld speed, filler wire feed rate and an expected value for the welding current by algorithmic function means, applying such values for weld speed and filler wire feed rate to the welding process, measuring the welding current, comparing the measured current to the calculated current, using said comparison to calculate corrections for the weld speed and filler wire feed rate, and applying corrections. 3 figs., 1 tab.

  3. Effects of shielding gas compositions on arc plasma and metal transfer in gas metal arc welding

    SciTech Connect (OSTI)

    Rao, Z. H.; Liao, S. M.; Tsai, H. L.

    2010-02-15

    This article presents the effects of shielding gas compositions on the transient transport phenomena, including the distributions of temperature, flow velocity, current density, and electromagnetic force in the arc and the metal, and arc pressure in gas metal arc welding of mild steel at a constant current input. The shielding gas considered includes pure argon, 75% Ar, 50% Ar, and 25% Ar with the balance of helium. It is found that the shielding gas composition has significant influences on the arc characteristics; droplet formation, detachment, transfer, and impingement onto the workpiece; and weld pool dynamics and weld bead profile. As helium increases in the shielding gas, the droplet size increases but the droplet detachment frequency decreases. For helium-rich gases, the current converges at the workpiece with a 'ring' shape which produces non-Gaussian-like distributions of arc pressure and temperature along the workpiece surface. Detailed explanations to the physics of the very complex but interesting transport phenomena are given.

  4. Study of the spray to globular transition in gas metal arc welding: a spectroscopic investigation

    E-Print Network [OSTI]

    Study of the spray to globular transition in gas metal arc welding: a spectroscopic investigation of the spray to globular transition in gas metal arc welding: a spectroscopic investigation F Valensi1.iop.org/JPhysD/46/224005 Abstract The gas metal arc welding (GMAW) process is strongly influenced by the composition

  5. Optical emission spectroscopy of metal vapor dominated laser-arc hybrid welding plasma

    SciTech Connect (OSTI)

    Ribic, B.; DebRoy, T.; Burgardt, P.

    2011-04-15

    During laser-arc hybrid welding, plasma properties affect the welding process and the weld quality. However, hybrid welding plasmas have not been systematically studied. Here we examine electron temperatures, species densities, and electrical conductivity for laser, arc, and laser-arc hybrid welding using optical emission spectroscopy. The effects of arc currents and heat source separation distances were examined because these parameters significantly affect weld quality. Time-average plasma electron temperatures, electron and ion densities, electrical conductivity, and arc stability decrease with increasing heat source separation distance during hybrid welding. Heat source separation distance affects these properties more significantly than the arc current within the range of currents considered. Improved arc stability and higher electrical conductivity of the hybrid welding plasma result from increased heat flux, electron temperatures, electron density, and metal vapor concentrations relative to arc or laser welding.

  6. Effects of current on droplet generation and arc plasma in gas metal arc welding

    SciTech Connect (OSTI)

    Hu, J.; Tsai, H. L.

    2006-09-01

    In gas metal arc welding (GMAW), a technology using pulsed currents has been employed to achieve the one-droplet-per-pulse (ODPP) metal transfer mode with the advantages of low average currents, a stable and controllable droplet generation, and reduced spatter. In this paper, a comprehensive model was developed to study the effects of different current profiles on the droplet formation, plasma generation, metal transfer, and weld pool dynamics in GMAW. Five types of welding currents were studied, including two constant currents and three wave form currents. In each type, the transient temperature and velocity distributions of the arc plasma and the molten metal, and the shapes of the droplet and the weld pool were calculated. The results showed that a higher current generates smaller droplets, higher droplet frequency, and higher electromagnetic force that becomes the dominant factor detaching the droplet from the electrode tip. The model has demonstrated that a stable ODPP metal transfer mode can be achieved by choosing a current with proper wave form for given welding conditions.

  7. Characterization of Gas Metal Arc Welding welds obtained with new high Cr-Mo ferritic stainless steel filler wires

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for homogeneous welding, by Gas Metal Arc Welding (GMAW) process, of a modified AISI 444 ferritic stainless steel, of the K44X assemblies are excellent. Keywords: ferritic stainless steel, welding, oxidation, tensile test of massive components, manifolds can now be made of stainless steel, using tubes or thin sheets rolled

  8. Computational Modeling of Microstructural-Evolution in AISI 1005 Steel During Gas Metal Arc Butt Welding

    E-Print Network [OSTI]

    Grujicic, Mica

    Welding M. Grujicic, S. Ramaswami, J.S. Snipes, R. Yavari, A. Arakere, C.-F. Yen, and B.A. Cheeseman-mechanical finite-element procedure is developed to model conventional gas metal arc welding (GMAW) butt of the workpiece and the weld temperature- dependent and by allowing the potential work of plastic deformation

  9. METAL TRANSFER CONTROL IN GAS METAL ARC WELDING L.A. Jones, T.W. Eagar, J.H. Lang

    E-Print Network [OSTI]

    Eagar, Thomas W.

    controls both the metal transfer process and the base-plate heating process. It would be advantageousMETAL TRANSFER CONTROL IN GAS METAL ARC WELDING L.A. Jones, T.W. Eagar, J.H. Lang Massachusetts, precision current control, and flexible real-time computer control is described. 1 Introduction Gas metal

  10. DC arc weld starter

    DOE Patents [OSTI]

    Campiotti, Richard H. (Tracy, CA); Hopwood, James E. (Oakley, CA)

    1990-01-01

    A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

  11. Contrib. Plasma Phys. 51, No. 2-3, 293 296 (2011) / DOI 10.1002/ctpp.201000061 LTE Experimental Validation in a Gas Metal Arc Welding Plasma

    E-Print Network [OSTI]

    2011-01-01

    Validation in a Gas Metal Arc Welding Plasma Column F. Valensi1,2 , S. Pellerin1 , A. Boutaghane3 , K, France 7 CTAS-Air Liquide Welding, Saint Ouen l'Aum^one, 95315 Cergy-Pontoise cedex, France Received 12 Spectroscopy, Boltzmann Plot, Sola method, LTE. During gas metal arc welding (GMAW), the plasma obtained has

  12. Ballistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel: A Computational

    E-Print Network [OSTI]

    Grujicic, Mica

    -welding of a prototypical high-hardness armor-grade martensitic steel, MIL A46100. The model predictions concerning-tempered, high-hardness, low-alloy martensitic, ar- mor-grade steel). A summary of Johnson-Cook material- modelBallistic-Failure Mechanisms in Gas Metal Arc Welds of Mil A46100 Armor-Grade Steel

  13. Microstructure evolution of Al/Mg butt joints welded by gas tungsten arc with Zn filler metal

    SciTech Connect (OSTI)

    Liu Fei; Zhang Zhaodong; Liu Liming, E-mail: liulm@dlut.edu.cn

    2012-07-15

    Based on the idea of alloying welding seam, Gas tungsten arc welding method with pure Zn filler metal was chosen to join Mg alloy and Al alloy. The microstructures, phases, element distribution and fracture morphology of welding seams were examined. The results indicate that there was a transitional zone in the width of 80-100 {mu}m between the Mg alloy substrate and fusion zone. The fusion zone was mainly composed of MgZn{sub 2}, Zn-based solid solution and Al-based solid solution. The welding seam presented distinct morphology in different location owning to the quite high cooling rate of the molten pool. The addition of Zn metal could prevent the formation of Mg-Al intermetallics and form the alloyed welding seam during welding. Therefore, the tensile strengths of joints have been significantly improved compared with those of gas tungsten arc welded joints without Zn metal added. Highlights: Black-Right-Pointing-Pointer Mg alloy AZ31B and Al alloy 6061 are welded successfully. Black-Right-Pointing-Pointer Zinc wire is employed as a filler metal to form the alloyed welding seam. Black-Right-Pointing-Pointer An alloyed welding seam is benefit for improving of the joint tensile strength.

  14. ~DELING OF METAL TRANSFKR IN GAS METAL ARC WELDING Yong -Seog Kim and T. W. Eagar

    E-Print Network [OSTI]

    Eagar, Thomas W.

    Massachusetts Institute of Technology ABSTRACT The droplet size is predicted using both the static force balance theory and the pinch i ns t a bility theor y as a function of welding cur rent . Experimental to explain metal transfer mechanisms. These include the static force balance theory (Refs. 2, 4), the pinch

  15. Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc Welding

    E-Print Network [OSTI]

    Grujicic, Mica

    Multiphysics Modeling and Simulations of Mil A46100 Armor-Grade Martensitic Steel Gas Metal Arc-welding of MIL A46100, a prototypical high-hardness armor martensitic steel. The model consists of five distinct) of a prototypical high-hardness armor-grade martensitic steel MIL A46100 (Ref 1). It is hoped that the availability

  16. Plasma diagnostics in gas metal arc welding by optical emission spectroscopy This article has been downloaded from IOPscience. Please scroll down to see the full text article.

    E-Print Network [OSTI]

    Plasma diagnostics in gas metal arc welding by optical emission spectroscopy This article has been welding by optical emission spectroscopy F Valensi1,2 , S Pellerin1 , A Boutaghane3 , K Dzierzega4 de Bourges), BP 4043, 18028 Bourges cedex, France 7 CTAS-Air Liquide Welding, Saint Ouen l

  17. Optimization of Gas Metal Arc Welding (GMAW) Process for Maximum Ballistic Limit in MIL A46100 Steel Welded

    E-Print Network [OSTI]

    Grujicic, Mica

    welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using filler-tempered, high-hardness, low-alloy martensitic, armor-grade steel) and validated by comparing the model Steel Welded All-Metal Armor M. Grujicic, S. Ramaswami, J.S. Snipes, R. Yavari, C.-F. Yen, and B

  18. Percussive arc welding apparatus

    DOE Patents [OSTI]

    Hollar, Jr., Donald L. (Overland Park, KS)

    2002-01-01

    A percussive arc welding apparatus includes a generally cylindrical actuator body having front and rear end portions and defining an internal recess. The front end of the body includes an opening. A solenoid assembly is provided in the rear end portion in the internal recess of the body, and an actuator shaft assembly is provided in the front end portion in the internal recess of the actuator body. The actuator shaft assembly includes a generally cylindrical actuator block having first and second end portions, and an actuator shaft having a front end extending through the opening in the actuator body, and the rear end connected to the first end portion of the actuator block. The second end portion of the actuator block is in operational engagement with the solenoid shaft by a non-rigid connection to reduce the adverse rebound effects of the actuator shaft. A generally transversely extending pin is rigidly secured to the rear end of the shaft. One end of the pin is received in a slot in the nose housing sleeve to prevent rotation of the actuator shaft during operation of the apparatus.

  19. Three-dimensional modeling of the plasma arc in arc welding

    SciTech Connect (OSTI)

    Xu, G.; Tsai, H. L.; Hu, J.

    2008-11-15

    Most previous three-dimensional modeling on gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW) focuses on the weld pool dynamics and assumes the two-dimensional axisymmetric Gaussian distributions for plasma arc pressure and heat flux. In this article, a three-dimensional plasma arc model is developed, and the distributions of velocity, pressure, temperature, current density, and magnetic field of the plasma arc are calculated by solving the conservation equations of mass, momentum, and energy, as well as part of the Maxwell's equations. This three-dimensional model can be used to study the nonaxisymmetric plasma arc caused by external perturbations such as an external magnetic field. It also provides more accurate boundary conditions when modeling the weld pool dynamics. The present work lays a foundation for true three-dimensional comprehensive modeling of GTAW and GMAW including the plasma arc, weld pool, and/or electrode.

  20. Welding arc initiator

    DOE Patents [OSTI]

    Correy, T.B.

    1989-05-09

    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.

  1. ABSTRACT. Keyhole plasma arc welding is a unique arc welding process for deep

    E-Print Network [OSTI]

    Zhang, YuMing

    ABSTRACT. Keyhole plasma arc welding is a unique arc welding process for deep penetration. To ensure the quality of the welds, the presence of the keyhole is crit- ical. Understanding of the keyhole will certainly benefit the improvement of the process and weld quality. Currently, the size of the keyhole

  2. Improved gas metal arc welding multi-physics process model and

    E-Print Network [OSTI]

    Grujicic, Mica

    -welding of MIL A46100 (a prototypical high-hardness armor-grade martensitic steel) workpieces using fillera, b, c). The present work deals with GMAW of armor-grade martensitic steels. In our prior work-grade steel butt-welds M. Grujicic, J.S. Snipes, R. Galgalikar, S. Ramaswami and R. Yavari Department

  3. Characterization of Mg/Al butt joints welded by gas tungsten arc filling with Zn–29.5Al–0.5Ti filler metal

    SciTech Connect (OSTI)

    Liu, Fei; Wang, Hongyang; Liu, Liming, E-mail: liulm@dlut.edu.cn

    2014-04-01

    The multivariate alloying design of a welding joint is used in the Mg to Al welding process. A Zn–29.5Al–0.5Ti alloy is added as filler metal in gas tungsten arc welding of Mg and Al alloy joint based on the analysis of Al and Mg alloy characteristics. The tensile strength, microstructure, and phase constitution of the weld seam are analyzed. The formation of brittle and hard Mg–Al intermetallic compounds is avoided because of the effects of Zn, Al, and Ti. The average tensile strength of the joint is 148 MPa. Al{sub 3}Ti is first precipitated and functions as the nucleus of heterogeneous nucleation during solidification. Moreover, the precipitated Al–MgZn{sub 2} hypoeutectic phase exhibited a feather-like structure, which enhances the property of the Mg–Al dissimilar joint. - Highlights: • Mg alloy AZ31B and Al alloy 6061 are butt welded by fusion welding. • The effect of Ti in filler metal is investigated. • The formation of Mg–Al intermetallic compounds is avoided.

  4. Costing of Joining Methods -Arc Welding Costs

    E-Print Network [OSTI]

    Colton, Jonathan S.

    Costing of Joining Methods - Arc Welding Costs ver. 1 ME 6222: Manufacturing Processes and Systems.S. Colton © GIT 2009 5 #12;LaborLabor Di t ti f ldi· Direct time of welding ­ time to produce a length of weld ­ labor rate ­ multiplication gives labor cost per length · Set-up time, etc. · Personal time

  5. Dynamic Behaviors of Plasma Reflection during Keyhole Arc Welding

    E-Print Network [OSTI]

    Zhang, YuMing

    Dynamic Behaviors of Plasma Reflection during Keyhole Arc Welding YuMing Zhang and Yi Ma Welding Engineering College of Engineering University of Kentucky #12;Keyhole Double-Sided Arc Welding Work PAW Torch: in any existing arc welding process? No ! Why Not in Keyhole PAW? No current through the keyhole ! Plasma

  6. WELDING RESEARCH -s229WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -s229WELDING JOURNAL ABSTRACT. Dual-bypass gas metal arc welding (DB agrees with experimental data. Introduction Gas metal arc welding (GMAW) is an arc welding process- minum alloy welded structures have been widely applied. The use of aluminum as an alternative material

  7. Gas-tungsten arc welding of aluminum alloys

    DOE Patents [OSTI]

    Frye, L.D.

    1982-03-25

    The present invention is directed to a gas-tungsten arc welding method for joining together structures formed of aluminum alloy with these structures disposed contiguously to a heat-damagable substrate of a metal dissimilar to the aluminum alloy. The method of the present invention is practiced by diamond machining the fay surfaces of the aluminum alloy structures to profice a mirror finish thereon having a surface roughness in the order of about one microinch. The fay surface are aligned and heated sufficiently by the tungsten electrode to fuse the aluminum alloy continguous to the fay surfaces to effect the weld joint. The heat input used to provide an oxide-free weld is significantly less than that required if the fay surfaces were prepared by using conventional chemical and mechanical practices.

  8. WELDING RESEARCH -s231WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -s231WELDING JOURNAL ABSTRACT. Double-electrode gas metal arc welding (DE the welding wire and the bypass torch. To control the base metal current at the desired level, a group. Introduction Gas metal arc welding (GMAW) is a major process for metals joining. Conventional GMAW is normally

  9. Thermocapillary and arc phenomena in stainless steel welds

    SciTech Connect (OSTI)

    Pierce, S.W.

    1993-10-01

    Goal was to study effect of power level and distribution on thermocapiilary-induced weld shape and of arc factors on weld shape. Thermocapillarity was apparent in both conduction mode EB welds and GTA welds, particularly in the former. A non-Gaussian arc distribution is suggested for accounting for the differences between the twoss processes. At higher current levels (200--300 A), plasma shear force also contributes to weld shape development. Evidence suggests that thermocapillary flow reversal is not a factor in normal GTA welds; EDB flow reversal occurs only at high power density levels where the keyhole mode is present.

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

    E-Print Network [OSTI]

    Keehan, Enda

    2004-01-01

    , Egypt The following papers were also published during the period, but are omitted in this thesis due to overlap or because the subject is outside the scope of this thesis: (10) (11) (12) (13) Göteborg, November 2004 VII Some wise words by fellow... 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 arc welding...

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

    E-Print Network [OSTI]

    Eagar, Thomas W.

    \\ 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

  12. Control of Gas Tungsten Arc welding pool shape by trace element addition to the weld pool

    DOE Patents [OSTI]

    Heiple, C.R.; Burgardt, P.

    1984-03-13

    An improved process for Gas Tungsten Arc welding maximizes the depth/width ratio of the weld pool by adding a sufficient amount of a surface active element to insure inward fluid flow, resulting in deep, narrow welds. The process is especially useful to eliminate variable weld penetration and shape in GTA welding of steels and stainless steels, particularly by using a sulfur-doped weld wire in a cold wire feed technique.

  13. Dilution Control in Gas-Tungsten-Arc Welds Involving Superaustenitic Stainless Steels and Nickel-Based Alloys

    E-Print Network [OSTI]

    DuPont, John N.

    ) were produced by varying the independent welding parameters of arc power and volumetric filler and decreasing arc power. These effects are quantitatively interpreted based on a previously proposed processing be correlated exclusively to the ratio of the volumetric filler-metal feed rate (Vfm) to arc power (VI), i

  14. A PRELIMINARY STUDY OF DOUBLE-SIDED ARC WELDING PROCESS IN SHIP STRUCTURE MANUFACTURING

    E-Print Network [OSTI]

    Zhang, YuMing

    A PRELIMINARY STUDY OF DOUBLE-SIDED ARC WELDING PROCESS IN SHIP STRUCTURE MANUFACTURING Yu Meeting, August 21-22, 2002 #12;Objective o Determine the feasibility of double-sided arc welding process in butt welding of DH-36 plates #12;Background: Process o Double-sided arc welding (DSAW): a novel arc

  15. Engineering Computations Modeling of ballistic-failure mechanisms in gas metal arc welds of mil a46100

    E-Print Network [OSTI]

    Grujicic, Mica

    -hardness armor-grade martensitic steel) workpieces using filler-metal electrodes made46100 armor-grade steel Mica Grujicic Subrahmanian Ramaswami Jennifer Snipes Rohan Galgalikar Ramin of mil a46100 armor-grade steel", Engineering Computations, Vol. 32 Iss 3 pp. 705 - 741 Permanent link

  16. Study of Mechanical Properties and Characterization of Pipe Steel welded by Hybrid (Friction Stir Weld + Root Arc Weld) Approach

    SciTech Connect (OSTI)

    Lim, Yong Chae [ORNL; Sanderson, Samuel [MegaStir Technologies LLC; Mahoney, Murray [Consultant; Wasson, Andrew J [ExxonMobil, Upstream Research Company (URC); Fairchild, Doug P [ExxonMobil, Upstream Research Company (URC); Wang, Yanli [ORNL; Feng, Zhili [ORNL

    2015-01-01

    Friction stir welding (FSW) has recently attracted attention as an alternative construction process for gas/oil transportation applications due to advantages compared to fusion welding techniques. A significant advantage is the ability of FSW to weld the entire or nearly the entire wall thickness in a single pass, while fusion welding requires multiple passes. However, when FSW is applied to a pipe or tube geometry, an internal back support anvil is required to resist the plunging forces exerted during FSW. Unfortunately, it may not be convenient or economical to use internal backing support due to limited access for some applications. To overcome this issue, ExxonMobil recently developed a new concept, combining root arc welding and FSW. That is, a root arc weld is made prior to FSW that supports the normal loads associated with FSW. In the present work, mechanical properties of a FSW + root arc welded pipe steel are reported including microstructure and microhardness.

  17. Stainless steel submerged arc weld fusion line toughness

    SciTech Connect (OSTI)

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

    1995-04-01

    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.

  18. WELDING RESEARCH -S59WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -S59WELDING JOURNAL ABSTRACT. The fatigue crack propaga- tion behavior of 316L stainless steel gas metal arc welds has been investigated using the K-increasing testing procedure. A series- come closure for all the gas metal arc welds tested. Crack closure measurements obtained through

  19. NEUTRAL-BEAM PLASMA SOURCE METAL-ARC PROTECTION CIRCUIT

    E-Print Network [OSTI]

    deVries, G.J.

    2010-01-01

    e r . METAL ARCS IN PLASMAS Metal-arcs in plasma sources are1981 NEUTRAL-BEAM PLASMA SOURCE METAL-ARC PROTECTION CIRCUIT48 NEUTRAL-BEAM PLASMA SOURCE METAL-ARC PROTECTION CIRCUIT*

  20. WELDING RESEARCH -s11WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -s11WELDING JOURNAL ABSTRACT. Double-electrode gas metal arc welding (DE-GMAW) is a novel weld- ing process recently developed to increase welding productivity while maintaining the base its non- consumable tungsten electrode with a consumable welding wire electrode result- ing in a new

  1. CHANGES IN SOLIDIFICATION MODE, AND THE MEASUREMENT OF COOLING RATES FOLLOWING SOLIDIFICATION DURING ARC WELDING

    E-Print Network [OSTI]

    Cambridge, University of

    SOLIDIFICATION DURING ARC WELDING 2.1 INTRODUCTION The solidification process in a weld pool has been shown to have a considerable in- fluence upon the properties of the resultant weld. It influences elements, and hence the homogeneity of the weld. Previous work on the cooling behaviour of welds (Garland

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

    SciTech Connect (OSTI)

    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

    2013-01-01

    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.

  3. Assessing Exposures to Particulate Matter and Manganese in Welding Fumes

    E-Print Network [OSTI]

    LIU, SA

    2010-01-01

    submerged arc welding and plasma arc welding. This study isAdministration PAW: plasma arc welding PEL: permissiblesubmerged arc welding and plasma arc welding. Overall

  4. Metals purification by improved vacuum arc remelting

    DOE Patents [OSTI]

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

    1994-12-13

    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.

  5. Method and device for reducing overpenetration at the start of plasma arc welds

    SciTech Connect (OSTI)

    Sanders, J.M.; Lehmann, J.M.; Ryan, P.M.

    2000-03-14

    A shim for improving plasma arc weld quality has ends tapered at about 25{degree} and notches at each end roughly centered over the corner between the tapered ends and main body of the shim. The improved shim allows lower starting plasma arc heat input and reduces the occurrence of sagging, or overpenetration, of the weld.

  6. Method and device for reducing overpenetration at the start of plasma arc welds

    DOE Patents [OSTI]

    Sanders, John M. (Jackson Township, Stark County, OH); Lehmann, John M. (Bedford County, VA); Ryan, Patrick M. (Washington Township, Stark County, OH)

    1998-01-01

    A shim for improving plasma arc weld quality has ends tapered at about 25.degree. and notches at each end roughly centered over the corner between the tapered ends and main body of the shim. The improved shim allows lower starting plasma arc heat input and reduces the occurrence of sagging, or overpenetration, of the weld.

  7. Improved Microstructure and Properties of 6061 Aluminum Alloy Weldments Using a Double-Sided Arc Welding

    E-Print Network [OSTI]

    Zhang, YuMing

    Welding Process Y.M. ZHANG, C. PAN, and A.T. MALE Due to its popularity and high crack sensitivity, 6061 aluminum alloy was selected as a test material for the newly developed double-sided arc welding (DSAW systematically. The percentage of fine equiaxed grains in the fully penetrated welds is greatly increased

  8. MULTIPLY STRIPPED ION GENERATION IN THE METAL VAPOR VACUUM ARC

    E-Print Network [OSTI]

    Brown, I.G.

    2010-01-01

    the metal vapor vacuum arc plasma discharge. A new kind offrom a metal vapor vacuum arc plasma has been used to obtaindrives the vacuum arc plasma is created. The fundamental

  9. Laser-Arc Hybrid Welding of Thick Section Ni-base Alloys – Advanced Modeling and Experiments

    SciTech Connect (OSTI)

    Debroy, Tarasankar; Palmer, Todd; Zhang, Wei

    2015-05-21

    Hybrid laser-arc welding of nickel-base alloys can increase productivity and decrease costs during construction and repair of critical components in nuclear power plants. However, laser and hybrid welding of nickel-base alloys is not well understood. This project sought to understand the physical processes during hybrid welding necessary to fabricate quality joints in Alloy 690, a Ni- Cr-Fe alloy. This document presents a summary of the data and results collected over the course of the project. The supporting documents are a collection of the research that has been or will be published in peer-reviewed journals along with a report from the partner at the national lab. Understanding the solidification behavior of Alloy 690 is important for knowing the final properties of the weldment. A study was undertaken to calculate the solidification parameters, such as temperature gradient, solidification rate, and cooling rate in Alloy 690 welds. With this information and measured cell and dendrite arm spacings, an Alloy 690 map was constructed to guide process parameter development and interpret fusion zones in later hybrid welds. This research is contained in “Solidification Map of a Nickel Base Alloy.” The keyhole formed under high laser intensity gives the hybrid welding technique the greater penetration depths compared to arc welding. However, keyhole behavior can form defects in the material, so knowing transient keyhole characteristics is important. With international collaborators, a study was undertaken to validate a new process monitoring tool known as inline coherent imaging (ICI), which is able to measure the keyhole depth with spatial and temporal resolutions on the order of 10 microns and 10 microseconds. ICI was validated for five alloy systems, including Alloy 690. Additionally, the keyhole growth rates at the start of welding were measured with unprecedented accuracy. This research is contained in “Real Time Monitoring of Laser Beam Welding Keyhole Depth by Laser Interferometry.” During full penetration welding of thick sections, root defects can form, which result in unacceptable weld quality. A study was undertaken to determine the competing forces in root defect formation by independently changing the weight forces and surface tension forces. The weight force was altered by changing the plate thickness, and the surface tension force was altered by changing the surface condition at the bottom surface. Root defects do depend on these two forces. This research is contained in “Mitigation of Root Defect in Laser and Hybrid Laser-Arc Welding.” Validation of the hybrid laser-arc model is necessary to properly model heat and mass transfer and fluid flow in Alloy 690 hybrid welds. Therefore, the developed model was validated for low carbon steel. Temperatures calculated by the model were included into a microstructural model in order to calculate the phase fractions. Process maps were developed for the selection of welding parameters to avoid martensite formation. This research is contained in “Fusion Zone Microstructure in Full Penetration Laser-Arc Hybrid Welding of Low Alloy Steel.” Alloy 690 suffers from ductility dip cracking, a form of hot cracking. This type of cracking inhibits the use of multipass welding to join Alloy 690. Our partners at ORNL performed some hot ductility testing with Alloy 690 samples using digital image correlation. The results of this work is contained in the report “Summary of 690 ductility dip cracking testing using Gleeble and digital image correlation.” Macro-porosity is a limiting factor in the widespread deployment of laser and hybrid laser-arc welding for construction and repair of nuclear power plant components. Keyhole instability and fluctuation results in the formation of large bubbles, which become trapped at the advancing solid- liquid interface as pores. Laser and hybrid laser-arc welds were fabricated for a range of conditions. Porosity levels in the welds were measured in X-ray computed tomography (CT), which provides very detailed data on the size and lo

  10. WELDING RESEARCH FEBRUARY 2008, VOL. 87-s44

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH FEBRUARY 2008, VOL. 87-s44 ABSTRACT. Consumable double- electrode gas metal arc welding (DE- GMAW) is an innovative welding process that can significantly increase the deposi- tion rate arc welding(GMAW)gunandconstantcurrent (CC) power supply to a conventional GMAW setup -- Fig. 1

  11. WELDING RESEARCH JANUARY 2004-S6

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH JANUARY 2004-S6 ABSTRACT. The influence of microstruc- ture on the fatigue crack propagation be- havior of gas metal arc welds in 316L and AL6XN austenitic stainless steels has been effects as the fatigue crack propa- gated from the base metal into the weld metal. The results

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

    SciTech Connect (OSTI)

    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)

    2014-02-18

    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.

  13. Video Game Device Haptic Interface for Robotic Arc Welding

    SciTech Connect (OSTI)

    Corrie I. Nichol; Milos Manic

    2009-05-01

    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.

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

    SciTech Connect (OSTI)

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

    2012-06-28

    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.

  15. Weld Surfacing Edited by Dr I.A. Bucklow

    E-Print Network [OSTI]

    Cambridge, University of

    V01.II Weld Surfacing Edited by Dr I.A. Bucklow ConferenceTechnicalDirector Organised by The Welding Institute in associationwith The Surface Engineering Society THE WELDING INSTITUTE #12;L becomesconfigurationally frozen at a temperature of about 1150°Cduring deposition by the manual-metal-arc welding technique

  16. Method for welding beryllium

    DOE Patents [OSTI]

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

    1997-01-01

    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.

  17. Influence of Mn and Ni on the microstructure and toughness of C-Mn-Ni weld metals

    SciTech Connect (OSTI)

    Zhang, Z.; Farrar, R.A. [Univ. of Southampton (United Kingdom). Dept. of Mechanical Engineering

    1997-05-01

    A systematic investigation has been carried out to study the microstructure and toughness of C-Mn-Ni low-alloy shielded metal arc (SMA) weld metals. The manganese and nickel concentrations were progressively changed to determine their influence on weld microstructure and mechanical properties as well as to identify their interactions. The results obtained showed that manganese and nickel have considerable effect on the weld metal microstructure, and both Mn and Ni affect the microstructure in a similar way, i.e., promoting acicular ferrite at the expense of proeutectoid ferrite (grain boundary ferrite and ferrite sideplates). The results in the top bead also showed that there is an optimum composition range that produces an optimum balance of weld metal microstructures. For optimum toughness, a combination of 0.6--1.4% manganese and 1.0--3.7% nickel is suggested. Additions beyond this limit promotes the formation of martensite and other microstructural features, which may be detrimental to weld metal toughness.

  18. Vacuum Arc Melting Unit Arc Melting is used for melting metals typically to form alloys. Heating is via an electric arc struck

    E-Print Network [OSTI]

    Subramaniam, Anandh

    Vacuum Arc Melting Unit Arc Melting is used for melting metals­ typically to form alloys. Heating unit is used as a power source. Heat generated by the electric arc struck between the electrode unit. The vacuum unit with rotary and diffusion pumps can attain a vacuum of 106 m bar. The cold

  19. PublishedbyManeyPublishing(c)IOMCommunicationsLtd Stainless steel weld metal designed to

    E-Print Network [OSTI]

    Cambridge, University of

    to be significantly better than commercially available martensitic stainless steel welding consumables, and it has transformation, Residual stress, Stainless steel, Martensitic, Transformation plasticity Introduction Residual weld metal could be based on a martensitic stainless steel. Although such alloys are available

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

    E-Print Network [OSTI]

    Kothari, Mitul Arvind

    2005-11-01

    Welding of metal matrix composites (MMCs) is an alternative to their mechanical joining, since they are difficult to machine. Published literature in fusion welding of similar composites shows metallurgical problems. This study investigates...

  1. Filler metal alloy for welding cast nickel aluminide alloys

    DOE Patents [OSTI]

    Santella, Michael L. (Knoxville, TN); Sikka, Vinod K. (Oak Ridge, TN)

    1998-01-01

    A filler metal alloy used as a filler for welding east nickel aluminide alloys contains from about 15 to about 17 wt. % chromium, from about 4 to about 5 wt. % aluminum, equal to or less than about 1.5 wt. % molybdenum, from about 1 to about 4.5 wt. % zirconium, equal to or less than about 0.01 wt. % yttrium, equal to or less than about 0.01 wt. % boron and the balance nickel. The filler metal alloy is made by melting and casting techniques such as are melting the components of the filler metal alloy and east in copper chill molds.

  2. Filler metal alloy for welding cast nickel aluminide alloys

    DOE Patents [OSTI]

    Santella, M.L.; Sikka, V.K.

    1998-03-10

    A filler metal alloy used as a filler for welding cast nickel aluminide alloys contains from about 15 to about 17 wt. % chromium, from about 4 to about 5 wt. % aluminum, equal to or less than about 1.5 wt. % molybdenum, from about 1 to about 4.5 wt. % zirconium, equal to or less than about 0.01 wt. % yttrium, equal to or less than about 0.01 wt. % boron and the balance nickel. The filler metal alloy is made by melting and casting techniques such as are melting the components of the filler metal alloy and cast in copper chill molds. 3 figs.

  3. Formation of metal oxides by cathodic arc deposition

    SciTech Connect (OSTI)

    Anders, S.; Anders, A.; Rubin, M.; Wang, Z.; Raoux, S.; Kong, F.; Brown, I.G.

    1995-03-01

    Metal oxide thin films are of interest for a number of applications. Cathodic arc deposition, an established, industrially applied technique for formation of nitrides (e.g. TiN), can also be used for metal oxide thin film formation. A cathodic arc plasma source with desired cathode material is operated in an oxygen atmosphere, and metal oxides of various stoichiometric composition can be formed on different substrates. We report here on a series of experiments on metal oxide formation by cathodic arc deposition for different applications. Black copper oxide has been deposited on ALS components to increase the radiative heat transfer between the parts. Various metal oxides such as tungsten oxide, niobium oxide, nickel oxide and vanadium oxide have been deposited on ITO glass to form electrochromic films for window applications. Tantalum oxide films are of interest for replacing polymer electrolytes. Optical waveguide structures can be formed by refractive index variation using oxide multilayers. We have synthesized multilayers of Al{sub 2}O{sub 3}/Y{sub 2}O{sub 3}/AI{sub 2}O{sub 3}/Si as possible basic structures for passive optoelectronic integrated circuits, and Al{sub 2-x}Er{sub x}O{sub 3} thin films with a variable Er concentration which is a potential component layer for the production of active optoelectronic integrated devices such as amplifiers or lasers at a wavelength of 1.53 {mu}m. Aluminum and chromium oxide films have been deposited on a number of substrates to impart improved corrosion resistance at high temperature. Titanium sub-oxides which are electrically conductive and corrosion resistant and stable in a number of aggressive environments have been deposited on various substrates. These sub-oxides are of great interest for use in electrochemical cells.

  4. BRITTLE FRACTURE IN HEAT-AFFECTED ZONES OF GIRTH WELDS OF MODERN LINE PIPE STEEL (X100)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    BRITTLE FRACTURE IN HEAT-AFFECTED ZONES OF GIRTH WELDS OF MODERN LINE PIPE STEEL (X100) A.-S. BILAT welds of modern line pipe steel, such as X100, issued from a pulsed automatic gas metal arc welding). The brittle zone is located in the coarse-grained heat-affected zone of the weld. The reproduction of two heat

  5. Svetsaren No.1 1999 53 High-strength weld metals fre-

    E-Print Network [OSTI]

    Cambridge, University of

    consisting of martensite or a mix- ture of martensite and acicular ferrite. The alloying of the weld metal temperature in mul- tirun welds. Introduction Making a high-strength steel us- ing a variety of well a reason- able compromise between strength and toughness. Unlike wrought steels, welds cannot usually

  6. A comparison of the marginal adaptation of cathode-arc vapor-deposited titanium and cast base metal copings.

    E-Print Network [OSTI]

    Wu, Jean C; Lai, Li-Chung; Sheets, Cherilyn G; Earthman, James; Newcomb, Robert

    2011-01-01

    of Prosthetic Dentistry plasma arc on the cathode surface.arc deposition consists of a titanium cathode material and metal plasma

  7. Laser welding and post weld treatment of modified 9Cr-1MoVNb steel.

    SciTech Connect (OSTI)

    Xu, Z.

    2012-04-03

    Laser welding and post weld laser treatment of modified 9Cr-1MoVNb steels (Grade P91) were performed in this preliminary study to investigate the feasibility of using laser welding process as a potential alternative to arc welding methods for solving the Type IV cracking problem in P91 steel welds. The mechanical and metallurgical testing of the pulsed Nd:YAG laser-welded samples shows the following conclusions: (1) both bead-on-plate and circumferential butt welds made by a pulsed Nd:YAG laser show good welds that are free of microcracks and porosity. The narrow heat affected zone has a homogeneous grain structure without conventional soft hardness zone where the Type IV cracking occurs in conventional arc welds. (2) The laser weld tests also show that the same laser welder has the potential to be used as a multi-function tool for weld surface remelting, glazing or post weld tempering to reduce the weld surface defects and to increase the cracking resistance and toughness of the welds. (3) The Vicker hardness of laser welds in the weld and heat affected zone was 420-500 HV with peak hardness in the HAZ compared to 240 HV of base metal. Post weld laser treatment was able to slightly reduce the peak hardness and smooth the hardness profile, but failed to bring the hardness down to below 300 HV due to insufficient time at temperature and too fast cooling rate after the time. Though optimal hardness of weld made by laser is to be determined for best weld strength, methods to achieve the post weld laser treatment temperature, time at the temperature and slow cooling rate need to be developed. (4) Mechanical testing of the laser weld and post weld laser treated samples need to be performed to evaluate the effects of laser post treatments such as surface remelting, glazing, re-hardening, or tempering on the strength of the welds.

  8. Fracture properties of a neutron-irradiated stainless steel submerged arc weld cladding overlay

    SciTech Connect (OSTI)

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The ability of stainless steel cladding to increase the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws depends greatly on the properties of the irradiated cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged arc, single-wire, oscillating-electrode method. Three layers of cladding provided a thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. The type 309 was diluted considerably by excessive melting of the base plate. Specimens were taken from near the base plate-cladding interface and also from the upper layers. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to a fluence of 2 x 10/sup 23/ neutrons/m/sup 2/ (>1 MeV). 10 refs., 16 figs., 4 tabs.

  9. 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]

    DeVore, Robin Kent

    1973-01-01

    fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1973 Major Subject: Industrial Hygiene THE EFFECTIVE SPECTRAL IRRADIANCE OF ULTRAVIOLET RADIATIONS FROM INERT-GAS-SHIELDED WELDING PROCESSES IN RELATION TO THE ARC CURRENT... DENSITY A Thesis by ROBIN KENT DEVORE Approved as to style and content by: C alarm n of o itte Hea o partment e er Member December 1973 ABSTRACT The Effective Spectral Irradiance of Ultraviolet Radiations from Inert-Gas-Shielded Welding...

  10. Method for welding beryllium

    DOE Patents [OSTI]

    Dixon, R.D.; Smith, F.M.; O`Leary, R.F.

    1997-04-01

    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. 9 figs.

  11. Towards Real Time Diagnostics of Hybrid Welding Laser/GMAW

    SciTech Connect (OSTI)

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

    2013-07-01

    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.

  12. Towards real time diagnostics of Hybrid Welding Laser/GMAW

    SciTech Connect (OSTI)

    McJunkin, T. R.; Kunerth, D. C.; Nichol, C. I. [Idaho National Laboratory, Idaho Falls, ID 83415-3570 (United States); Todorov, E.; Levesque, S. [Edison Welding Institute, Columbus, OH (United States)

    2014-02-18

    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.

  13. Modelling of friction stir welding

    E-Print Network [OSTI]

    Colegrove, Paul Andrew

    the operator does not require the skills required for arc welding. • No edge preparation, shielding gas or filler metal is required. (Although shielding gas is used for some high temperature materials.) • Low distortion, shrinkage and residual stresses... is Friction Stir Processing, where material is processed (without being welded) to improve its mechanical properties. This enables the casting of components that are cun'ently machined with the clitical areas being processed to improve their hardness and...

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

    SciTech Connect (OSTI)

    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

    2012-06-28

    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.

  15. High power x-ray welding of metal-matrix composites

    DOE Patents [OSTI]

    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)

    1999-01-01

    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.

  16. High-bandwidth continuous-flow arc furnace

    DOE Patents [OSTI]

    Hardt, D.E.; Lee, S.G.

    1996-08-06

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics. 4 figs.

  17. High-bandwidth continuous-flow arc furnace

    DOE Patents [OSTI]

    Hardt, David E. (Concord, MA); Lee, Steven G. (Ann Arbor, MI)

    1996-01-01

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics.

  18. Ductile filler metal alloys for welding nickel aluminide alloys

    DOE Patents [OSTI]

    Santella, Michael L. (Knoxville, TN); McNabb, Jeffrey D. (Lenoir City, TN); Sikka, Vinod K. (Oak Ridge, TN)

    2003-04-08

    Nickel aluminum alloys are welded utilizing a nickel based alloy containing zirconium but substantially free of titanium and niobium which reduces the tendency to crack.

  19. Arc Plasma Torch Modeling

    E-Print Network [OSTI]

    Trelles, J P; Vardelle, A; Heberlein, J V R

    2013-01-01

    Arc plasma torches are the primary components of various industrial thermal plasma processes involving plasma spraying, metal cutting and welding, thermal plasma CVD, metal melting and remelting, waste treatment and gas production. They are relatively simple devices whose operation implies intricate thermal, chemical, electrical, and fluid dynamics phenomena. Modeling may be used as a means to better understand the physical processes involved in their operation. This paper presents an overview of the main aspects involved in the modeling of DC arc plasma torches: the mathematical models including thermodynamic and chemical non-equilibrium models, turbulent and radiative transport, thermodynamic and transport property calculation, boundary conditions and arc reattachment models. It focuses on the conventional plasma torches used for plasma spraying that include a hot-cathode and a nozzle anode.

  20. Laser welding of annealed Zr55Cu30Ni5Al10 bulk metallic glass B. Chen a,b

    E-Print Network [OSTI]

    Li, Mo

    welded specimen plates with no obvious welding defects in the joints and high welding speed may lead, it becomes increasingly difficult to form complex structures because of the high flow stress in the mold shaping of BMG parts with complex shapes and geometry. In addition, it is difficult to produce metal molds

  1. Pressure Resistance Welding of High Temperature Metallic Materials

    SciTech Connect (OSTI)

    N. Jerred; L. Zirker; I. Charit; J. Cole; M. Frary; D. Butt; M. Meyer; K. L. Murty

    2010-10-01

    Pressure Resistance Welding (PRW) is a solid state joining process used for various high temperature metallic materials (Oxide dispersion strengthened alloys of MA957, MA754; martensitic alloy HT-9, tungsten etc.) for advanced nuclear reactor applications. A new PRW machine has been installed at the Center for Advanced Energy Studies (CAES) in Idaho Falls for conducting joining research for nuclear applications. The key emphasis has been on understanding processing-microstructure-property relationships. Initial studies have shown that sound joints can be made between dissimilar materials such as MA957 alloy cladding tubes and HT-9 end plugs, and MA754 and HT-9 coupons. Limited burst testing of MA957/HT-9 joints carried out at various pressures up to 400oC has shown encouraging results in that the joint regions do not develop any cracking. Similar joint strength observations have also been made by performing simple bend tests. Detailed microstructural studies using SEM/EBSD tools and fatigue crack growth studies of MA754/HT-9 joints are ongoing.

  2. Pressure Resistance Welding of High Temperature Metallic Materials

    SciTech Connect (OSTI)

    Larry Zirker; Craig Tyler

    2010-08-01

    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.

  3. Increasing Productivity of Welding 

    E-Print Network [OSTI]

    Uhrig, J. J.

    1983-01-01

    It is universally recognized that welding is the most economical way to permanently join metals. Recent advances in welding, specifically, the continuous electrode wire processes make welding even more attractive for manufacturing. As welding...

  4. WELDING RESEARCH -S249WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -S249WELDING JOURNAL ABSTRACT. Double-sided arcing uses two torches on the opposite sides of the workpiece to force the welding current to flow through the thickness. If a keyhole is established through the thickness, part of the welding current will flow through the keyhole and maintain

  5. Effect of welding on impact toughness of butt-joints in a titanium alloy

    E-Print Network [OSTI]

    Zhou, Wei

    Effect of welding on impact toughness of butt-joints in a titanium alloy Wei Zhou a, *, K.G. Chew b Abstract Impact toughness of a gas tungsten arc welded TiÁ/6AlÁ/4V alloy butt-joint was evaluated at room located either in the parent metal, in the heat- affected zone (HAZ), or in the weld metal. Optical

  6. Probe characterization of high-current driven metal plasma in a vacuum-arc rail gun

    SciTech Connect (OSTI)

    Vijayan, T.; Roychowdhury, P.; Venkatramani, N.

    2004-10-15

    The characteristics of metal plasma launched by high-current electric arc in a vacuum-arc rail gun are determined by employing electrical and magnetic probes. These measurements are validated by results from theoretical simulations. The arc coupled nonlinear circuit equations are solved simultaneously with the Newtonian arc motion and revealed the undercritically damped behavior of the arc current identical to the arc-current signal recorded by the Rogowski magnetic probe. Similarly the arc velocity and displacement derived from the signatures of B-dot probes are shown to concur closely with the results of JxB propulsion from simulation. The heating of plasma is formulated in a three-electron population regime with direct arc energy coupling through magnetohydrodynamic, ion-acoustic, Coulomb, and neutral interactions. This results in high temperature (T{sub e}) of hundreds of eV in the arc as revealed by the simulation. Hence T{sub e} of the rapidly cooling and equilibrating plasma that emerged from the muzzle is high around 80-90 eV, which is confirmed by Langmuir electric probe measurements. Density n{sub e} of this metal plasma is shown to be in the range 4x10{sup 21}-6x10{sup 21} m{sup -3} and includes multiple ion charge states. The exit velocity of the plasma measured by a pair of Langmuir probes is close to 2.2x10{sup 6} cm/s and matched well with the arc velocity determined by the B-dot probes and the results from simulation.

  7. Method for laser welding ultra-thin metal foils

    DOE Patents [OSTI]

    Pernicka, J.C.; Benson, D.K.; Tracy, C.E.

    1996-03-26

    A method for simultaneously cutting and welding ultra-thin foils having a thickness of less than 0.002 inches wherein two ultra-thin films are stacked and clamped together. A pulsed laser such as of the Neodymium: YAG type is provided and the beam of the laser is directed onto the stacked films to cut a channel through the films. The laser is moved relative to the stacked foils to cut the stacked foils at successive locations and to form a plurality of connected weld beads to form a continuous weld. 5 figs.

  8. Method for laser welding ultra-thin metal foils

    DOE Patents [OSTI]

    Pernicka, John C. (Fort Collins, CO); Benson, David K. (Golden, CO); Tracy, C. Edwin (Golden, CO)

    1996-01-01

    A method for simultaneously cutting and welding ultra-thin foils having a thickness of less than 0.002 inches wherein two ultra-thin films are stacked and clamped together. A pulsed laser such as of the Neodymium: YAG type is provided and the beam of the laser is directed onto the stacked films to cut a channel through the films. The laser is moved relative to the stacked foils to cut the stacked foils at successive locations and to form a plurality of connected weld beads to form a continuous weld.

  9. Multi-cathode metal vapor arc ion source

    DOE Patents [OSTI]

    Brown, Ian G. (1088 Woodside Rd., Berkeley, CA 94708); MacGill, Robert A. (645 Kern St., Richmond, CA 94805)

    1988-01-01

    An ion generating apparatus utilizing a vacuum chamber, a cathode and an anode in the chamber. A source of electrical power produces an arc or discharge between the cathode and anode. The arc is sufficient to vaporize a portion of the cathode to form a plasma. The plasma is directed to an extractor which separates the electrons from the plasma, and accelerates the ions to produce an ion beam. One embodiment of the appaatus utilizes a multi-cathode arrangement for interaction with the anode.

  10. Upgraded HFIR Fuel Element Welding System

    SciTech Connect (OSTI)

    Sease, John D [ORNL

    2010-02-01

    The welding of aluminum-clad fuel plates into aluminum alloy 6061 side plate tubing is a unique design feature of the High Flux Isotope Reactor (HFIR) fuel assemblies as 101 full-penetration circumferential gas metal arc welds (GMAW) are required in the fabrication of each assembly. In a HFIR fuel assembly, 540 aluminum-clad fuel plates are assembled into two nested annular fuel elements 610 mm (24-inches) long. The welding process for the HFIR fuel elements was developed in the early 1960 s and about 450 HFIR fuel assemblies have been successfully welded using the GMAW process qualified in the 1960 s. In recent years because of the degradation of the electronic and mechanical components in the old HFIR welding system, reportable defects in plate attachment or adapter welds have been present in almost all completed fuel assemblies. In October 2008, a contract was awarded to AMET, Inc., of Rexburg, Idaho, to replace the old welding equipment with standard commercially available welding components to the maximum extent possible while maintaining the qualified HFIR welding process. The upgraded HFIR welding system represents a major improvement in the welding system used in welding HFIR fuel elements for the previous 40 years. In this upgrade, the new inner GMAW torch is a significant advancement over the original inner GMAW torch previously used. The innovative breakthrough in the new inner welding torch design is the way the direction of the cast in the 0.762 mm (0.030-inch) diameter aluminum weld wire is changed so that the weld wire emerging from the contact tip is straight in the plane perpendicular to the welding direction without creating any significant drag resistance in the feeding of the weld wire.

  11. Method of beam welding metallic parts together and apparatus for doing same

    DOE Patents [OSTI]

    Lewandowski, Edward F. (Westmont, IL); Cassidy, Dale A. (Valparaiso, IN); Sommer, Robert G. (Lemont, IL)

    1987-01-01

    The disclosed method provides for temporarily clamping a metallic piece to one side of a metallic plate while leaving the opposite side of the plate exposed, and providing a heat conductive heat sink body configured to engage the adjacent portions of such one side of the plate and the piece at all regions proximate to but not at the interface between these components. Such exposed side of such plate is then subjected to an electron welding beam, in exact registry with but opposite to the piece. The electron welding beam is supplied with adequate energy for penetrating through the plate, across the interface, and into the piece, whereby the electron welding beam produces molten material from both the plate and the piece in the region of the interface. The molten material flows into any interstices that may exist in the interface, and upon cooling solidifies to provide a welded joint between the plate and piece, where the interface was, virtually without any interstices. The heat sink material prevents the molten material from extruding beyond what was the interface, to provide a clean welded joint. The heat sink body also mechanically holds the plate and piece together prior to the actual welding.

  12. Method of beam welding metallic parts together and apparatus for doing same

    DOE Patents [OSTI]

    Lewandowski, E.F.; Cassidy, D.A.; Sommer, R.G.

    1985-11-29

    This method provides for temporarily clamping a metallic piece to one side of a metallic plate while leaving the opposite side of the plate exposed, and providing a heat conductive heat sink body configured to engage the adjacent portions of such one side of the plate and the piece at all regions proximate to but not at the interface between these components. The exposed side of such plate is then subjected to an electron welding beam, in exact registry with but opposite to the piece. The electron welding beam is supplied with adequate energy for penetrating through the plate, across the interface, and into the piece, whereby the electron welding beam produces molten material from both the plate and the piece in the region of the interface. The molten material flows into any interstices that may exist in the interface, and upon cooling solidifies to provide a welded joint between the plate and piece, where the interface was, virtually without any interstices. The heat sink material prevents the molten material from extrucing beyond what was the interface, to provide a clean welded joint. The heat sink body also mechanically holds the plate and piece together prior to the actual welding.

  13. Charpy toughness and tensile properties of a neutron irradiated stainless steel submerged-arc weld cladding overlay

    SciTech Connect (OSTI)

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-01-01

    The possibility of stainless steel cladding increasing the resistance of an operating nuclear reactor pressure vessel to extension of surface flaws is highly dependent upon the irradiated properties of the cladding. Therefore, weld overlay cladding irradiated at temperatures and fluences relevant to power reactor operation was examined. The cladding was applied to a pressure vessel steel plate by the submerged-arc, single-wire, oscillating electrode method. Three layers of cladding were applied to provide a cladding thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. There was considerable dilution of the type 309 in the first layer of cladding as a result of excessive melting of the base plate. Specimens for the irradiation study were taken from near the base plate/cladding interface and also from the upper layers of cladding. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to neutron fluences of 2 x 10/sup 23/ n/m/sup 2/ (E > 1 MeV). When irradiated, both types 308 and 309 cladding showed a 5 to 40% increase in yield strength accompanied by a slight increase in ductility in the temperature range from 25 to 288/sup 0/C. All cladding exhibited ductile-to-brittle transition behavior during impact testing.

  14. Precipitation of sigma and chi phases in ?-ferrite of Type 316FR weld metals

    SciTech Connect (OSTI)

    Chun, Eun Joon; Baba, Hayato; Nishimoto, Kazutoshi; Saida, Kazuyoshi

    2013-12-15

    The decomposition behavior and kinetics of ?-ferrite are examined using aging treatments between 873 and 1073 K for Type 316FR stainless steel weld metals with different solidification modes (316FR AF, 316FR FA). The dominant precipitates are sigma, chi, and secondary austenite nucleated at ?-ferrite/austenite interfaces or in the interior of the ferrite grains. These precipitates consume all the ferrite during isothermal aging in both 316FR AF and FA weld metals. Differences in the precipitation behavior (precipitation initiation time and precipitation speed) between weld metals can be explained by i) the degree of Cr and Mo microsegregation within ?-ferrite or austenite near ferrite and ii) the nucleation sites induced due to the solidification mode (AF or FA), such as the ferrite amount. For both weld materials, a Johnson–Mehl-type equation can express the precipitation behavior of the sigma + chi phases and quantitatively predict the behavior at the service-exposure temperatures of a fast breed reactor. - Highlights: • Precipitation of ? and ? phase in Type 316FR welds (two solidification modes) • Different precipitation behaviors: precipitation initiation time and growth speed • Johnson-Mehl–type equation is the most applicable to the precipitation behaviors • Precipitation behaviors are predicted under service conditions of FBRs.

  15. IR-Laser Welding and Ablation of Biotissue Stained with Metal Nanoparticles

    E-Print Network [OSTI]

    Lalayan, A A

    2015-01-01

    In the present work we have studied the possibility of laser welding and ablation of biological tissue by the using of spherical metal nanoparticles (NPs) and infrared laser irradiation which spectrally located far from plasmon resonances. YAG:Nd laser with 1064 nm wavelength, 8 ns pulse duration, and operating in transverse electromagnetic modes TEM$_{00}$ was used for the synthesis of metal NPs. The Au,Ti Ni and Cu as well as Au-Ag and Au-Cu hybrid metal NPs were formed in the liquid medium. Effectiveness of laser ablation in the case of the biotissue sample that stained with the metal NPs was approximately on 4-5 times larger than for the native sample. Also the scheme of a laser point welding for the deep-located biotissue layer selectively stained by the metal NPs has been demonstrated.

  16. WELDING RESEARCH -s55WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -s55WELDING JOURNAL ABSTRACT. Dissimilar metal weld (DMW) failures between carbon along the weld interface and the formation of locally high stresses associated with thermal ex- pansion mismatch. The formation of a soft carbon denuded region near the weld in- terface has been identified

  17. Investigation of fracture mechanical behavior of nodular cast iron and welded joints with parent-material-like weld metal

    SciTech Connect (OSTI)

    Baer, W.; Pusch, G.

    1995-12-31

    The focus of the investigations was the determination of fracture mechanical characteristics and crack resistance curves of the J-Integral and CTOD concept by application of the partial unloading compliance technique and D.C. potential drop technique (four point bend) under static load. The results show a close correlation between crack initiation values as well as crack resistance curves and graphite morphology parameters determined by means of quantitative microstructural analysis where the influence of the matrix (distance of graphite particles) dominates the crack resistance and fracture performance of ferritic nodular cast iron under consideration of the notch effect of graphite particles. SEM in-situ tensile tests showed that due to a beneficial shielding effect of the strength overmatching parent-material-like weld metal (mis-match ratio M = 1.21), cracks positioned directly in the plane of the fusion line did not deviate into the weld metal in spite of its lower toughness compared to that of the parent material. They also showed an unsymmetrical formation of damage in front of the crack tip.

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

    E-Print Network [OSTI]

    Eagar, Thomas W.

    condensation on the side of the electrode. I. INTRODUCTION THE shielding gas composition is a critical process. Massachusens Institute of Technology. Cambridge, MA 02 {39. Manuscript submitted August II. 1993- stead, a 90 pet helium-10 pet iron vapor gas mixture was used in the calculations. A more in

  19. Charpy toughness and tensile properties of a neutron-irradiated stainless steel submerged arc weld cladding overlay

    SciTech Connect (OSTI)

    Corwin, W.R.; Berggren, R.G.; Nanstad, R.K.

    1984-09-01

    The cladding was applied to a pressure vessel steel plate by the submerged arc, single-wire, oscillating-electrode method. Three layers of cladding provided a thickness adequate for fabrication of test specimens. The first layer was type 309, and the upper two layers were type 308 stainless steel. The type 309 was diluted considerably by excessive melting of the base plate. Specimens were taken from near the base plate-cladding interface and also from the upper layers. Charpy V-notch and tensile specimens were irradiated at 288/sup 0/C to a fluence of 2 x 10/sup 23/ neutrons/m/sup 2/ (>1 MeV). When irradiated, both types 308 and 309 cladding increased 5 to 40% in yield strength and slightly increased in ductility in the temperature range from 25 to 288/sup 0/C. All cladding exhibited ductile-to-brittle transition behavior during impact testing. The type 308 cladding, microstructurally typical of that in reactor pressure vessels, showed very little degradation in either upper-shelf energy or transition temperature due to irradiation. Conversely, the impact properties of the specimens containing the highly diluted type 309 cladding, microstructurally similar to that produced during some off-normal welding conditions in existing reactors, experienced significant increases in transition temperature and drops of up to 50% in upper-shelf energy. The impact energies of the Charpy specimens containing the type 309 layer strongly reflected the amount of the type 309 actually in the specimen, falling into two distinct high- and low-energy populations with the low-energy population corresponding to a higher fraction of type 309 in the specimen.

  20. High current multicharged metal ion source using high power gyrotron heating of vacuum arc plasma

    SciTech Connect (OSTI)

    Vodopyanov, A. V.; Golubev, S. V.; Khizhnyak, V. I.; Mansfeld, D. A.; Nikolaev, A. G.; Oks, E. M.; Savkin, K. P.; Vizir, A. V.; Yushkov, G. Yu.

    2008-02-15

    A high current, multi charged, metal ion source using electron heating of vacuum arc plasma by high power gyrotron radiation has been developed. The plasma is confined in a simple mirror trap with peak magnetic field in the plug up to 2.5 T, mirror ratio of 3-5, and length variable from 15 to 20 cm. Plasma formed by a cathodic vacuum arc is injected into the trap either (i) axially using a compact vacuum arc plasma gun located on axis outside the mirror trap region or (ii) radially using four plasma guns surrounding the trap at midplane. Microwave heating of the mirror-confined, vacuum arc plasma is accomplished by gyrotron microwave radiation of frequency 75 GHz, power up to 200 kW, and pulse duration up to 150 {mu}s, leading to additional stripping of metal ions by electron impact. Pulsed beams of platinum ions with charge state up to 10+, a mean charge state over 6+, and total (all charge states) beam current of a few hundred milliamperes have been formed.

  1. Summary of Dissimilar Metal Joining Trials Conducted by Edison Welding Institute

    SciTech Connect (OSTI)

    MJ Lambert

    2005-11-18

    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.

  2. WELDING RESEARCH -S125WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -S125WELDING JOURNAL ABSTRACT. Microstructural evolution and solidification cracking susceptibility of dissimilar metal welds between AL- 6XN super austenitic stainless steel and two, differential thermal analysis, and Varestraint testing tech- niques. Welds were prepared over the en- tire

  3. Use of vacuum arc plasma guns for a metal puff Z-pinch system

    SciTech Connect (OSTI)

    Rousskikh, A. G.; Zhigalin, A. S.; Oreshkin, V. I.; Chaikovsky, S. A.; Labetskaya, N. A.; Baksht, R. B.

    2011-09-15

    The performance of a metal puff Z-pinch system has been studied experimentally. In this type of system, the initial cylindrical shell 4 cm in diameter was produced by ten plasma guns. Each gun initiates a vacuum arc operating between magnesium electrodes. The net current of the guns was 80 kA. The arc-produced plasma shell was compressed by using a 450-kA, 450-ns driver, and as a result, a plasma column 0.3 cm in diameter was formed. The electron temperature of the plasma reached 400 eV at an average ion concentration of 1.85 {center_dot} 10{sup 18} cm{sup -3}. The power of the Mg K-line radiation emitted by the plasma for 15-30 ns was 300 MW/cm.

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

    SciTech Connect (OSTI)

    P.Andreson

    2004-10-01

    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.

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

    SciTech Connect (OSTI)

    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)

    2013-08-15

    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.

  6. Plasma arc torch with coaxial wire feed

    DOE Patents [OSTI]

    Hooper, Frederick M (Albuquerque, NM)

    2002-01-01

    A plasma arc welding apparatus having a coaxial wire feed. The apparatus includes a plasma arc welding torch, a wire guide disposed coaxially inside of the plasma arc welding torch, and a hollow non-consumable electrode. The coaxial wire guide feeds non-electrified filler wire through the tip of the hollow non-consumable electrode during plasma arc welding. Non-electrified filler wires as small as 0.010 inches can be used. This invention allows precision control of the positioning and feeding of the filler wire during plasma arc welding. Since the non-electrified filler wire is fed coaxially through the center of the plasma arc torch's electrode and nozzle, the wire is automatically aimed at the optimum point in the weld zone. Therefore, there is no need for additional equipment to position and feed the filler wire from the side before or during welding.

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

    SciTech Connect (OSTI)

    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)

    2014-02-18

    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.

  8. Gas Metal Arc Welding Process Modeling and Prediction of Weld Microstructure in MIL A46100 Armor-Grade

    E-Print Network [OSTI]

    Grujicic, Mica

    -Grade Martensitic Steel M. Grujicic, A. Arakere, S. Ramaswami, J.S. Snipes, R. Yavari, C-F. Yen, B.A. Cheeseman-metallurgy, to a prototypical high-hardness armor martensitic steel (MIL A46100). The main outcome of this procedure-metallurgy concepts and principles of a prototypical high-hardness armor-grade martensitic steel MIL A46100 [Ref 1

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

    E-Print Network [OSTI]

    Fehrenbacher, Mary Catherine

    1984-01-01

    EVALUATION OF A PORTABLE X-RAY FLUORE~ SURVEY METER FOR TIIE QUANTITATIVE DEPERMINATI(gq OF TRACE METALS IN WELDING FIJvtES A THESIS by MARY CATHERINE FEHRENBACHER Submitted to the Graduate College of Texas A%M University in partial... fulfillment of the requirement for the degree of MASTER OF SCIENCE May, 1984 MAJOR SUBJECI': INDUSTRIAL HYGIENE EVALUATION OF A PORTABLE X-RAY FLUORES~ SURVEY METER FOR THE QUANTITATIVE DETERMINATIGN OF TRACE METALS IN WELDING FIJvtES A THESIS by h...

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

    E-Print Network [OSTI]

    Owen, Richard James

    1976-01-01

    DETERMINATION OF WELDING FUME SIZE WITH TIME USING E7018 ELECTRODES AND A131B BASE METAL A Thesis by RICHARD JAMES OWEN Submitted to the Graduate College of Texas AILM University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1976 Major Subject: Industrial Hygiene DETERMINATION OF WELDING FUME SIZE WITH TIME USING E7018 ELECTRODES AND Al 318 BASE METAL A Thesis by RICHARD JAMES OWEN Approved as to style and content by: Cha&rman of Comm t ad...

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

    SciTech Connect (OSTI)

    John N. DuPont

    2010-03-01

    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.

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

    E-Print Network [OSTI]

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

    2004-01-01

    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...

  13. Transformation Plasticity in Steel Weld Metals H. K. D. H. Bhadeshia, J. A. Francis, H. J. Stone, S. Kundu

    E-Print Network [OSTI]

    Cambridge, University of

    Transformation Plasticity in Steel Weld Metals H. K. D. H. Bhadeshia, J. A. Francis, H. J. Stone, S transformation is particularly important when dealing with martensite or bainite. These phases evolve, a phenomenon intrinsic to the mechanical behaviour of TRIP­ assisted steels. The subject of this paper

  14. A MODEL FOR THE STRENGTH OF THE AS-DEPOSITED REGIONS OF LOW-ALLOY STEEL WELD METALS

    E-Print Network [OSTI]

    Cambridge, University of

    true average strain ~ true plastic strain in softer phase of a dual-phase steel ~I true plastic strain in harder phase of a dual-phase steel UTS true strain at ultimate tensile stress y true strain at yieldingCHAPTER 5 A MODEL FOR THE STRENGTH OF THE AS-DEPOSITED REGIONS OF LOW-ALLOY STEEL WELD METALS 5

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

    SciTech Connect (OSTI)

    Nikolaev, A. G.; Savkin, K. P.; Oks, E. M.; Vizir, A. V.; Yushkov, G. Yu.; Vodopyanov, A. V.; Izotov, I. V.; Mansfeld, D. A.

    2012-02-15

    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.

  16. Characterization of Arc Generated Plasma Interactions with a Liquid Metal Medium

    SciTech Connect (OSTI)

    Hahn, Gregory C.; Martin, Elijah H.; Bourham, Mohamed A.

    2005-05-15

    Plasma interaction with first wall and interior reactor chamber components is an influencing factor in the design of inertial fusion facilities. The concept of a liquid metal wall, in which a circulating lithium curtain would be used, has been considered in many studies. The interaction of plasmas with moving liquid metals is a complex subject due to the influence of hydrodynamics, evaporation and droplet formation, nucleation and agglomeration of condensed particulates. To gain an understanding of some of the specific details of this interaction an experimental setup of an arc-generated plasma interacting with a liquid lead pool has been designed, constructed and operated. This simulation of the plasma-liquid interaction focuses on the particle condensation of the liquid metal after plasma interaction. The experiment generates transient high-density plasma over 50 {mu}s pulse duration. Plasma characteristics are determined by various diagnostics. A set of collection substrates are arranged to collect nucleated particulates condensing from the evolving plume. Particulate size and distribution are analyzed numerically using digital images.

  17. Effect of rapid solidification on stainless steel weld metal microstructures and its implications on the Schaeffler diagram

    SciTech Connect (OSTI)

    David, S.A.; Vitek, J.M.; Reed, R.W.; Hebble, T.L.

    1987-09-01

    An investigation was carried out to determine the effect of rapid solidification on the weld metal microstructure of austenitic stainless steels and its implication on the ferrite constitution diagram. A wide variety of stainless steels were laser welded at different welding speeds and laser power levels. Results indicate that both weld pool cooling rate and the postsolidification solid state cooling rates have a profound effect on the microstructures. For the steels investigated, the microstructures ranged from duplex austenite (..gamma..) + ferrite (delta) to fully austenitic or fully ferritic. These microstructures were found to be sensitive to both cooling rates and composition. The observed results are rationalized based on rapid solidification theory. This investigation indicates that solidification rates and postsolidification cooling rates have a profound effect on the observed microstructures, thus making it impossible to predict the microstructures of rapidly cooled weld metal from the conventional constitution diagrams. The influence of the observations made in this investigation on the Schaeffler diagram is demonstrated, and possible corrections to the constitution diagram incorporating the cooling rate effects are proposed. 23 refs., 17 figs., 4 tabs.

  18. Weld microstructure development and properties of precipitation-strengthened martensitic stainless steels

    SciTech Connect (OSTI)

    Brooks, J.A. ); Garrison, W.R. Jr. )

    1999-08-01

    The weld microstructural evolution, mechanical properties and solidification cracking susceptibility of three precipitation-strengthened martensitic stainless steels--PH 13-8 Mo, Custom 450 and 15-5 PH--were investigated. Liquid tin quenching of gas tungsten arc welds revealed that all three welds solidified as single-phase ferrite with a high degree of microsegregation. However, during further solidification and cooling almost complete homogenization occurred as a result of solid-state diffusion. The welds in all three alloys exhibited good resistance to solidification cracking and generally exhibited tensile and impact properties similar to those of the base metal. However, in almost all cases, the weld Charpy impact energies were somewhat less than those of the base metals. The cracking behavior and mechanical properties are discussed in terms of microstructural evolution.

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

    E-Print Network [OSTI]

    Anders, Georgy, Yu. Yushkov, Andre

    2008-01-01

    of expanding vacuum arc plasmas”, IEEE Trans. Plasma Sci. ,in high current vacuum arc plasma in a magnetic field,” IEEEdistributions of vacuum arc plasmas: The origin of species”,

  20. Chapter 7 -Welding The dangers in welding, cutting, heating and grinding should never be underestimated.

    E-Print Network [OSTI]

    Tullos, Desiree

    36 Chapter 7 - Welding The dangers in welding, cutting, heating and grinding should never and to understand the hazards involved. Spot the hazard Hazards associated with welding include: · The arc itself eyes can become extremely red and sore and in extreme cases suffer permanent damage. · Welding gases

  1. Plasma effect on weld pool surface reconstruction by shape-from-polarization analysis

    SciTech Connect (OSTI)

    Coniglio, N.; Mathieu, A.

    2014-03-31

    The polarimetric state of the thermal radiations emitted by the weld metal contains geometric information about the emitting surface. Even though the analysed thermal radiation has a wavelength corresponding to a blind spectral window of the arc plasma, the physical presence of the arc plasma itself interferes with the rays radiated by the weld pool surface before attaining the polarimeter, thus modifying the geometric information transported by the ray. In the present work, the effect of the arc plasma-surrounding zone on the polarimetric state and propagation direction of the radiated ray is analyzed. The interaction with the arc plasma zone induces a drop in ray intensity and a refraction of ray optical path.

  2. Fusion Welding of AerMet 100 Alloy

    SciTech Connect (OSTI)

    ENGLEHART, DAVID A.; MICHAEL, JOSEPH R.; NOVOTNY, PAUL M.; ROBINO, CHARLES V.

    1999-08-01

    A database of mechanical properties for weldment fusion and heat-affected zones was established for AerMet{reg_sign}100 alloy, and a study of the welding metallurgy of the alloy was conducted. The properties database was developed for a matrix of weld processes (electron beam and gas-tungsten arc) welding parameters (heat inputs) and post-weld heat treatment (PWHT) conditions. In order to insure commercial utility and acceptance, the matrix was commensurate with commercial welding technology and practice. Second, the mechanical properties were correlated with fundamental understanding of microstructure and microstructural evolution in this alloy. Finally, assessments of optimal weld process/PWHT combinations for cotildent application of the alloy in probable service conditions were made. The database of weldment mechanical properties demonstrated that a wide range of properties can be obtained in welds in this alloy. In addition, it was demonstrated that acceptable welds, some with near base metal properties, could be produced from several different initial heat treatments. This capability provides a means for defining process parameters and PWHT's to achieve appropriate properties for different applications, and provides useful flexibility in design and manufacturing. The database also indicated that an important region in welds is the softened region which develops in the heat-affected zone (HAZ) and analysis within the welding metallurgy studies indicated that the development of this region is governed by a complex interaction of precipitate overaging and austenite formation. Models and experimental data were therefore developed to describe overaging and austenite formation during thermal cycling. These models and experimental data can be applied to essentially any thermal cycle, and provide a basis for predicting the evolution of microstructure and properties during thermal processing.

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

    E-Print Network [OSTI]

    Hixon, Jeff

    2006-01-01

    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 ...

  4. Simultaneous laser cutting and welding of metal foil to edge of a plate

    DOE Patents [OSTI]

    Pernicka, John C. (Fort Collins, CO); Benson, David K. (Golden, CO); Tracy, C. Edwin (Golden, CO)

    1996-01-01

    A method of welding an ultra-thin foil to the edge of a thicker sheet to form a vacuum insulation panel comprising the steps of providing an ultra-thin foil having a thickness less than 0.002, providing a top plate having an edge and a bottom plate having an edge, clamping the foil to the edge of the plate wherein the clamps act as heat sinks to distribute heat through the foil, providing a laser, moving the laser relative to the foil and the plate edges to form overlapping weld beads to weld the foil to the plate edges while simultaneously cutting the foil along the weld line formed by the overlapping beads.

  5. Simultaneous laser cutting and welding of metal foil to edge of a plate

    DOE Patents [OSTI]

    Pernicka, J.C.; Benson, D.K.; Tracy, C.E.

    1996-03-19

    A method is described for welding an ultra-thin foil to the edge of a thicker sheet to form a vacuum insulation panel comprising the steps of providing an ultra-thin foil having a thickness less than 0.002, providing a top plate having an edge and a bottom plate having an edge, clamping the foil to the edge of the plate wherein the clamps act as heat sinks to distribute heat through the foil, providing a laser, moving the laser relative to the foil and the plate edges to form overlapping weld beads to weld the foil to the plate edges while simultaneously cutting the foil along the weld line formed by the overlapping beads. 7 figs.

  6. Effect of a copper filler metal on the microstructure and mechanical properties of electron beam welded titanium-stainless steel joint

    SciTech Connect (OSTI)

    Wang, Ting, E-mail: fgwangting@163.com [Key Laboratory of Special Welding in Shandong Province, Harbin Institute of Technology at Weihai, Weihai, 264209 (China)] [Key Laboratory of Special Welding in Shandong Province, Harbin Institute of Technology at Weihai, Weihai, 264209 (China); Zhang, Binggang, E-mail: zhang_bg@126.com [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001 (China)] [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001 (China); Feng, Jicai, E-mail: fengjc@hit.edu.cn [Key Laboratory of Special Welding in Shandong Province, Harbin Institute of Technology at Weihai, Weihai, 264209 (China) [Key Laboratory of Special Welding in Shandong Province, Harbin Institute of Technology at Weihai, Weihai, 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001 (China); Tang, Qi, E-mail: tangqi@163.com [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001 (China)] [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin, 150001 (China)

    2012-11-15

    Cracking in an electron beam weld of titanium to stainless steel occurred during the cooling process because of internal thermal stress. Using a copper filler metal, a crack free joint was obtained, which had a tensile strength of 310 MPa. To determine the reasons for cracking in the Ti/Fe joint and the function of the copper filler metal on the improvement of the cracking resistance of the Ti/Cu/Fe joint, the microstructures of the joints were studied by optical microscopy, scanning electron microscopy and X-ray diffraction. The cracking susceptibilities of the joints were evaluated with microhardness tests on the cross-sections. In addition, microindentation tests were used to compare the brittleness of the intermetallics in the welds. The results showed that the Ti/Fe joint was characterized by continuously distributed brittle intermetallics such as TiFe and TiFe(Cr){sub 2} with high hardness ({approx} 1200 HV). For the Ti/Cu/Fe joint, most of the weld consisted of a soft solid solution of copper with dispersed TiFe intermetallics. The transition region between the weld and the titanium alloy was made up of a relatively soft Ti-Cu intermetallic layer with a lower hardness ({approx} 500 HV). The formation of soft phases reduced the cracking susceptibility of the joint. - Highlights: Black-Right-Pointing-Pointer Electron beam welded Ti/Fe joint cracked for the brittleness and residual stress. Black-Right-Pointing-Pointer Electron beam welded Ti/Cu/Fe joint with tensile strength of 310 MPa was obtained. Black-Right-Pointing-Pointer Cu diluted Ti and Fe contents in weld and separated the TiFe{sub 2} into individual blocks. Black-Right-Pointing-Pointer Interfacial hard Ti-Fe compounds were replaced by soft Ti-Cu compounds in the weld. Black-Right-Pointing-Pointer A large amount of solid solution of copper formed in the weld.

  7. TABLE OF CONTENTS Welding and Cutting

    E-Print Network [OSTI]

    US Army Corps of Engineers

    EM 385-1-1 30 Nov 14 10-i Section 10 TABLE OF CONTENTS Welding and Cutting Section: Page 10.A ............................................................................................... 10-5 10.E Oxyfuel Gas Welding and Cutting .................................................................. 10-7 10.F Arc Welding and Cutting

  8. UC Berkeley Welding/Cutting Permit

    E-Print Network [OSTI]

    Cohen, Ronald C.

    #12;#12;UC Berkeley Welding/Cutting Permit MUST BE POSTED ON SITE All equipment to be used for welding or cutting has been inspected and approved. All personnel (including supervisors) are trained, or protected by fire-resistant shields. (Where floors have been wet down, personnel operating arc welding

  9. TRITIUM AGING EFFECTS ON THE FRACTURE TOUGHNESS PROPERTIES OF STAINLESS STEEL BASE METAL AND WELDS

    SciTech Connect (OSTI)

    Morgan, M.

    2009-07-30

    Tritium reservoirs are constructed from welded stainless steel forgings. While these steels are highly resistant to the embrittling effects of hydrogen isotopes and helium from tritium decay; they are not immune. Tritium embrittlement is an enhanced form of hydrogen embrittlement because of the presence of helium-3 from tritium decay which nucleates as nanometer-sized bubbles on dislocations, grain boundaries, and other microstructural defects. Steels with decay helium bubble microstructures are hardened and less able to deform plastically and become more susceptible to embrittlement by hydrogen and its isotopes. Ductility, elongation-to-failure, and fracture toughness are reduced by exposures to tritium and the reductions increase with time as helium-3 builds into the material from tritium permeation and radioactive decay. Material and forging specifications have been developed for optimal material compatibility with tritium. These specifications cover composition, mechanical properties, and select microstructural characteristics like grain size, flow-line orientation, inclusion content, and ferrite distribution. For many years, the forming process of choice for reservoir manufacturing was high-energy-rate forging (HERF), principally because the DOE forging facility owned only HERF hammers. Today, some reservoir forgings are being made that use a conventional, more common process known as press forging (PF or CF). One of the chief differences between the two forging processes is strain rate: Conventional hydraulic or mechanical forging presses deform the metal at 4-8 ft/s, about ten-fold slower than the HERF process. The material specifications continue to provide successful stockpile performance by ensuring that the two forging processes produce similar reservoir microstructures. While long-term life storage tests have demonstrated the general tritium compatibility of tritium reservoirs, fracture-toughness properties of both conventionally forged and high-energy-rate forged are needed for designing and establishing longer tritium-reservoir lifetimes, ranking materials, and, potentially, for qualifying new forging vendors or processes. Measurements on the effects of tritium and decay helium on the fracture toughness properties of CF stainless steels having similar composition, grain size, and mechanical properties to previously studied HERF steels are needed and have not been conducted until now. The compatibility of stainless steel welds with tritium represents another concern for long-term reservoir performance. Weldments have not been well-characterized with respect to tritium embrittlement, although a recent study was completed on the effect of tritium and decay helium on the fracture toughness properties of Type 304L weldments. This study expands the characterization of weldments through measurements of tritium and decay helium effects on the fracture toughness properties of Type 21-6-9 stainless steel. The purpose of this study was to measure and compare the fracture toughness properties of Type 21-6-9 stainless steel for conventional forgings and weldments in the non-charged, hydrogen-charged and tritium-charged-and-aged conditions.

  10. The problem of intermixing of metals possessing no mutual solubility upon explosion welding (Cu-Ta, Fe-Ag, Al-Ta)

    SciTech Connect (OSTI)

    Greenberg, B.A., E-mail: bella@imp.uran.ru [Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, S. Kovalevskoi str. 18, Ekaterinburg, 620990 (Russian Federation); Ivanov, M.A. [Kurdyumov Institute of Metal Physics, National Academy of Sciences of Ukraine, Vernadskogo blvd. 36, Kiev, 03680 (Ukraine)] [Kurdyumov Institute of Metal Physics, National Academy of Sciences of Ukraine, Vernadskogo blvd. 36, Kiev, 03680 (Ukraine); Rybin, V.V. [State Polytechnical University, Politekhnicheskaya str. 29, St. Petersburg, 195251 (Russian Federation)] [State Polytechnical University, Politekhnicheskaya str. 29, St. Petersburg, 195251 (Russian Federation); Elkina, O.A.; Antonova, O.V.; Patselov, A.M.; Inozemtsev, A.V.; Plotnikov, A.V.; Volkova, A.Yu. [Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, S. Kovalevskoi str. 18, Ekaterinburg, 620990 (Russian Federation)] [Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, S. Kovalevskoi str. 18, Ekaterinburg, 620990 (Russian Federation); Besshaposhnikov, Yu.P. [OJSC Ural Chemical Machine Building Plant, Khibinogorskii Lane 33, Ekaterinburg, 620010 (Russian Federation)] [OJSC Ural Chemical Machine Building Plant, Khibinogorskii Lane 33, Ekaterinburg, 620010 (Russian Federation)

    2013-01-15

    On the basis of the results obtained for joints of dissimilar metals such as copper-tantalum and iron-silver, the reason of immiscible suspensions mixing upon explosion welding has been cleared out. It has been found that the interface (plain or wavy) is not smooth and contains inhomogeneities, namely, cusps and local melting zones. The role of granulating fragmentation providing partitioning of initial materials as a main channel of input energy dissipation has been revealed. It has been shown that in joints of metals possessing normal solubility the local melting zones are true solutions, but if metals possess no mutual solubility the local melting zones are colloidal solutions. Realization of either emulsion or suspension variant takes place. The results can be used in the development of new joints of metals possessing no mutual solubility. - Highlights: Black-Right-Pointing-Pointer Immiscible pairs Ta/Cu and Fe/Ag are welded successfully by explosive welding. Black-Right-Pointing-Pointer Fragmentation provides for partitioning as the main energy dissipation channel. Black-Right-Pointing-Pointer Immiscible metals form colloidal solid solutions during solidification. Black-Right-Pointing-Pointer Melting and boiling temperatures ratio determines the colloidal solution type. Black-Right-Pointing-Pointer Local melting zones being in suspension form enhance welds hardening.

  11. MCWASP, Modeling of Casting, Welding and Advanced Solidification Processes XI TMS (The Minerals, Metals & Materials Society),

    E-Print Network [OSTI]

    Zabaras, Nicholas J.

    at the bottom of the casting due to shrinkage driven fluid flow leads to a non-uniform solute distributionMCWASP, Modeling of Casting, Welding and Advanced Solidification Processes XI TMS (The Minerals, Aluminum alloys, Cast surfaces, Mold topography, Inverse segregation, Imperfect contact, Air-gaps, Solid

  12. Irradiation effects on fracture toughness of two high-copper submerged-arc welds, HSSI series 5. Volume 2, Appendices E and F

    SciTech Connect (OSTI)

    Nanstad, R.K.; Haggag, F.M.; McCabe, D.E.; Iskander, S.K.; Bowman, K.O. [Oak Ridge National Lab., TN (United States); Menke, B.H. [Materials Engineering Associates, Inc., Lanham, MD (United States)

    1992-10-01

    The Fifth Irradiation Series in the Heavy-Section Steel irradiation (HSSI) Program was aimed at obtaining a statistically significant fracture toughness data base on two weldments with high-copper contents to determine the shift and shape of the K{sub lc} curve as a consequence of irradiation. The program included irradiated Charpy V-notch impact, tensile, and drop-weight specimens in addition to compact fracture toughness specimens. Compact specimens with thicknesses of 25.4, 50.8, and 101.6 mm [1T C(T), 2T C(T), and 4T C(T), respectively] were irradiated. Additionally, unirradiated 6T C(T) and 8T C(T) specimens with the same K{sub lc} measuring capacity as the irradiated specimens were tested. The materials for this irradiation series were two weldments fabricated from special heats of weld wire with copper added to the melt. One lot of Linde 0124 flux was used for all the welds. Copper levels for the two welds are 0.23 and 0.31 wt %, while the nickel contents for both welds are 0.60 wt %. Twelve capsules of specimens were irradiated in the pool-side facility of the Oak Ridge Research Reactor at a nominal temperature of 288{degree}C and an average fluence of about 1.5 {times} 10{sup 19} neutrons/cm{sup 2} (> 1 MeV). This volume, Appendices E and F, contains the load-displacement curves and photographs of the fracture toughness specimens from the 72W weld (0.23 wt % Cu) and the 73 W weld (0.31 wt % Cu), respectively.

  13. A comparison of the marginal adaptation of cathode-arc vapor-deposited titanium and cast base metal copings.

    E-Print Network [OSTI]

    Wu, Jean C; Lai, Li-Chung; Sheets, Cherilyn G; Earthman, James; Newcomb, Robert

    2011-01-01

    thick, dark titanium oxide layer. The new cathode-arc vaporcolor of the titanium oxide layer resulted in compromised

  14. The evolution of ion charge states in cathodic vacuum arc plasmas: a review

    E-Print Network [OSTI]

    Anders, Andre

    2013-01-01

    in metal vapor vacuum arc plasmas and ion sources," Plasmathe separation of cathodic arc plasma and macroparticles incharge states in vacuum arc plasmas in a magnetic field,"

  15. Soluble transition metals cause the pro-inflammatory effects of welding fumes in vitro 

    E-Print Network [OSTI]

    McNeilly, Jane D; Heal, Mathew R; Beverland, Iain J; Howe, Alan; Gibson, Mark D; Hibbs, Leon; MacNee, William; Donaldson, Ken

    2004-01-01

    Epidemiological studies have consistently reported a higher incidence of respiratory illnesses such as bronchitis, metal fume fever (MFF), and chronic pneumonitis among welders exposed to high concentrations of metal-enriched ...

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

    DOE Patents [OSTI]

    Ren, Weiju

    2014-11-11

    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.

  17. Cathodic arcs

    E-Print Network [OSTI]

    Anders, Andre

    2003-01-01

    Rectangular vacuum-arc plasma source, Jan. 2, 1996. [40] A.A. Anders, Cathodic Arc Plasma Deposition (in preparation) (from the cathodic arc plasma. In most cases, a magnetic

  18. Method for enhanced control of welding processes

    DOE Patents [OSTI]

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

    2000-01-01

    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.

  19. Inverter-based GTA welding machines improve fabrication

    SciTech Connect (OSTI)

    Sammons, M.

    2000-05-01

    While known as precision process, many fabricators using the gas tungsten arc welding (GTAW) process fight several common problems that hinder quality, slow production, frustrate the operator and otherwise prevent the process from achieving its full potential. These include a limited ability to tailor the weld bead profile, poor control of the arc direction and arc wandering, poor arc starting, unstable or inconsistent arcs in the AC mode, high-frequency interference with electronics and tungsten contamination. Fortunately, new GTA welding technology--made possible by advances with inverter-based power sources and micro-processor controls--can eliminate common productivity gremlins. Further, new AC/DC inverter-based GTA power sources provide advanced arc shaping capabilities. As a result, many fabricators adopting this new technology have experienced phenomenal production increases, taken on new types of projects and reduced costs. Most importantly, the operators enjoy welding more.

  20. Narrow groove welding gas diffuser assembly and welding torch

    DOE Patents [OSTI]

    Rooney, Stephen J. (East Berne, NY)

    2001-01-01

    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.

  1. Next Generation Metallic Iron Nodule Technology in Electric Arc Steelmaking - Phase II

    SciTech Connect (OSTI)

    Donald R. Fosnacht; Iwao Iwasaki; Richard F. Kiesel; David J. Englund; David W. Hendrickson; Rodney L. Bleifuss

    2010-12-22

    The current trend in the steel industry is a gradual decline in conventional steelmaking from taconite pellets in blast furnaces, and an increasing number of alternative processes using metallic scrap iron, pig iron and metallized iron ore products. Currently, iron ores from Minnesota and Michigan are pelletized and shipped to the lower Great Lakes ports as blast furnace feed. The existing transportation system and infrastructure is geared to handling these bulk materials. In order to expand the opportunities for the existing iron ore mines beyond their blast furnace customer base, a new material is needed to satisfy the needs of the emerging steel industry while utilizing the existing infrastructure and materials handling. A recent commercial installation employing Kobe Steel’s ITmk3 process, was installed in Northeastern Minnesota. The basic process uses a moving hearth furnace to directly reduce iron oxides to metallic iron from a mixture of iron ore, coals and additives. The resulting products can be shipped using the existing infrastructure for use in various steelmaking processes. The technology reportedly saves energy by 30% over the current integrated steelmaking process and reduces emissions by more than 40%. A similar large-scale pilot plant campaign is also currently in progress using JFE Steel’s Hi-QIP process in Japan. The objective of this proposal is to build upon and improve the technology demonstrated by Kobe Steel and JFE, by further reducing cost, improving quality and creating added incentive for commercial development. This project expands previous research conducted at the University of Minnesota Duluth’s Natural Resources Research Institute and that reported by Kobe and JFE Steel. Three major issues have been identified and are addressed in this project for producing high-quality nodular reduced iron (NRI) at low cost: (1) reduce the processing temperature, (2) control the furnace gas atmosphere over the NRI, and (3) effectively use sub-bituminous coal as a reductant. From over 4000 laboratory tube and box furnace tests, it was established that the correct combination of additives, fluxes, and reductant while controlling the concentration of CO and CO2 in the furnace atmosphere (a) lowers the operating temperature, (b) decreases the use of reductant coal (c) generates less micro nodules of iron, and (d) promotes desulphurization. The laboratory scale work was subsequently verified on 12.2 m (40 ft) long pilot scale furnace. High quality NRI could be produced on a routine basis using the pilot furnace facility with energy provided from oxy-gas or oxy-coal burner technologies. Specific strategies were developed to allow the use of sub-bituminous coals both as a hearth material and as part of the reaction mixture. Computational Fluid Dynamics (CFD) modeling was used to study the overall carbothermic reduction and smelting process. The movement of the furnace gas on a pilot hearth furnace and larger simulated furnaces and various means of controlling the gas atmosphere were evaluated. Various atmosphere control methods were identified and tested during the course of the investigation. Based on the results, the appropriate modifications to the furnace were made and tested at the pilot scale. A series of reduction and smelting tests were conducted to verify the utility of the processing conditions. During this phase, the overall energy use characteristics, raw materials, alternative fuels, and the overall economics predicted for full scale implementation were analyzed. The results indicate that it should be possible to lower reaction temperatures while simultaneously producing low sulfur, high carbon NRI if the right mix chemistry and atmosphere are employed. Recommendations for moving the technology to the next stage of commercialization are presented.

  2. Material property evaluations of bimetallic welds, stainless steel saw fusion lines, and materials affected by dynamic strain aging

    SciTech Connect (OSTI)

    Rudland, D.; Scott, P.; Marschall, C.; Wilkowski, G. [Battelle Memorial Institute, Columbus, OH (United States)

    1997-04-01

    Pipe fracture analyses can often reasonably predict the behavior of flawed piping. However, there are material applications with uncertainties in fracture behavior. This paper summarizes work on three such cases. First, the fracture behavior of bimetallic welds are discussed. The purpose of the study was to determine if current fracture analyses can predict the response of pipe with flaws in bimetallic welds. The weld joined sections of A516 Grade 70 carbon steel to F316 stainless steel. The crack was along the carbon steel base metal to Inconel 182 weld metal fusion line. Material properties from tensile and C(T) specimens were used to predict large pipe response. The major conclusion from the work is that fracture behavior of the weld could be evaluated with reasonable accuracy using properties of the carbon steel pipe and conventional J-estimation analyses. However, results may not be generally true for all bimetallic welds. Second, the toughness of austenitic steel submerged-arc weld (SAW) fusion lines is discussed. During large-scale pipe tests with flaws in the center of the SAW, the crack tended to grow into the fusion line. The fracture toughness of the base metal, the SAW, and the fusion line were determined and compared. The major conclusion reached is that although the fusion line had a higher initiation toughness than the weld metal, the fusion-line J-R curve reached a steady-state value while the SAW J-R curve increased. Last, carbon steel fracture experiments containing circumferential flaws with periods of unstable crack jumps during steady ductile tearing are discussed. These instabilities are believed to be due to dynamic strain aging (DSA). The paper discusses DSA, a screening criteria developed to predict DSA, and the ability of the current J-based methodologies to assess the effect of these crack instabilities. The effect of loading rate on the strength and toughness of several different carbon steel pipes at LWR temperatures is also discussed.

  3. Predicting the Failure of Ultrasonic Spot Welds by Pull-out from Sheet Metal

    E-Print Network [OSTI]

    Thouless, Michael

    -mode fracture of the base metal, the cohesive parameters for ductile fracture of an aluminum alloy were parameters (characteristic strength and toughness) associated with the shear and normal modes of ductile, cohesive zone, fracture, cohesive strength, toughness. (March 2006) #12;2 1. Introduction Ultrasonic spot

  4. WELDING RESEARCH -s51WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    . The use of nickel- based filler metals produces a thinner martensite layer compared to stainless steel alloy welds. The concentration gradients were converted to martensite start (Ms) tem- perature gradients and used to explain the differences in martensite layer widths that have been observed in the partially

  5. Effects of irradiation temperature on Charpy and tensile properties of high-copper, low upper-shelf, submerged-arc welds

    SciTech Connect (OSTI)

    Nanstad, R.K.; Berggren, R.G.

    1992-12-31

    This paper presents analyses of the Charpy impact and tensile test data, including adjustments for irradiation temperature and fluence normalization which make possible comparison of the irradiation sensitivity of the different welds. Analyses revealed dependence of yield and ultimate strength on irradiation temperature {minus}0.8 MPA/{degrees}C, respectively. Similarly, the Charpy impact energy changes due to irradiation temperature were {minus}0.5{degrees}C/{degrees}C for transition shift and {minus}0.05 J/{degrees}C for upper-shelf energy decrease. After adjustment to an irradiation temperature of 288{degrees}C and normalization to a fluence of 8 {times} 10{sup 18} neutrons/cm{sup 2} percentage increases in yield strength due to irradiation ranged from about 21 to 35% while those for ultimate strength ranged from about 13 to 20%. The Charpy transition temperature shifts ranged from 59 to 123{degrees}C while the postirradiation upper-shelf energies ranged from 58 to 79 J.

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

    SciTech Connect (OSTI)

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

    2014-03-24

    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.

  7. Welding apparatus and methods for using ultrasonic sensing

    DOE Patents [OSTI]

    McJunkin, Timothy R.; Johnson, John A.; Larsen, Eric D.; Smartt, Herschel B.

    2006-08-22

    A welding apparatus using ultrasonic sensing is described and which includes a movable welder having a selectively adjustable welding head for forming a partially completed weld in a weld seam defined between adjoining metal substrates; an ultrasonic assembly borne by the moveable welder and which is operable to generate an ultrasonic signal which is directed toward the partially completed weld, and is further reflected from same; and a controller electrically coupled with the ultrasonic assembly and controllably coupled with the welding head, and wherein the controller receives information regarding the ultrasonic signal and in response to the information optimally positions the welding head relative to the weld seam.

  8. Evidence for neutron irradiation-induced metallic precipitates in model alloys and pressure-vessel weld steel

    E-Print Network [OSTI]

    Motta, Arthur T.

    -vessel weld steel Stephen E. Cumblidge a , Arthur T. Motta a,*, Gary L. Catchen a , Gerhard Brauer b , Juurgen-irradiated model alloys (1 · 1023 n/m2 , E > 0:5 MeV) and 73W-weld steel (to 1.8 · 1023 n/m2 , E > 1 Me examined in the as-irradiated state and after post-irradiation isochronal anneals to temperature up to 600

  9. Weld failure detection

    DOE Patents [OSTI]

    Pennell, William E. (Unity Township, Westmoreland County, PA); Sutton, Jr., Harry G. (Mt. Lebanon, PA)

    1981-01-01

    Method and apparatus for detecting failure in a welded connection, particrly applicable to not readily accessible welds such as those joining components within the reactor vessel of a nuclear reactor system. A preselected tag gas is sealed within a chamber which extends through selected portions of the base metal and weld deposit. In the event of a failure, such as development of a crack extending from the chamber to an outer surface, the tag gas is released. The environment about the welded area is directed to an analyzer which, in the event of presence of the tag gas, evidences the failure. A trigger gas can be included with the tag gas to actuate the analyzer.

  10. ON THE CURRENT INTENSITY LIMIT OF A VACUUM ARC ION SOURCE

    E-Print Network [OSTI]

    Brown, I.G.

    2011-01-01

    for the metal vapor vacuum arc plasma discharge employed. inin the basic vacuum arc plasma source, and we have drawnThe vacuum arc is a prolific source of metal plasma, and the

  11. Filtered cathodic arc source

    DOE Patents [OSTI]

    Falabella, S.; Sanders, D.M.

    1994-01-18

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge is described. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45[degree] to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles. 3 figures.

  12. A comparison of the marginal adaptation of cathode-arc vapor-deposited titanium and cast base metal copings.

    E-Print Network [OSTI]

    Wu, Jean C; Lai, Li-Chung; Sheets, Cherilyn G; Earthman, James; Newcomb, Robert

    2011-01-01

    invest- ment, and casting of metal alloys are potentialusing ti- tanium and base metal castings was that they havenique-sensitive method of casting this base metal alloy. The

  13. Hot cracking in tungsten inert gas welding of magnesium alloy AZ91D

    E-Print Network [OSTI]

    Zhou, Wei

    Hot cracking in tungsten inert gas welding of magnesium alloy AZ91D W. Zhou*, T. Z. Long and C. K of the plates were produced using tungsten inert gas (TIG) welding method. The TIG arc was also used to deposit welding beads on some of the thin plates. No cracking was found in the butt joints. However, hot cracking

  14. Method for laser welding a fin and a tube

    DOE Patents [OSTI]

    Fuerschbach, Phillip W. (Tijeras, NM); Mahoney, A. Roderick (Albuquerque, NM); Milewski, John O (Santa Fe, NM)

    2001-01-01

    A method of laser welding a planar metal surface to a cylindrical metal surface is provided, first placing a planar metal surface into approximate contact with a cylindrical metal surface to form a juncture area to be welded, the planar metal surface and cylindrical metal surface thereby forming an acute angle of contact. A laser beam, produced, for example, by a Nd:YAG pulsed laser, is focused through the acute angle of contact at the juncture area to be welded, with the laser beam heating the juncture area to a welding temperature to cause welding to occur between the planar metal surface and the cylindrical metal surface. Both the planar metal surface and cylindrical metal surface are made from a reflective metal, including copper, copper alloys, stainless steel alloys, aluminum, and aluminum alloys.

  15. Architecture of the Object Oriented ARC framework

    E-Print Network [OSTI]

    Joshi, Rushikesh K.

    in the ARC logical ring ARC Sotware Components ARC Sotware Components ARC Sotware Components ARC Sotware Components ARC Sotware Components > > >

  16. WELDING RESEARCH -s85WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -s85WELDING JOURNAL ABSTRACT. Measurement of weld pool surface is a difficult but urgent task in the welding community. It plays an important role not only in developing the next- generation intelligent welding machines but also for modeling complex welding processes. In recent years

  17. Photoelectron Emission from Metal Surfaces Induced by VUV-emission of Filament Driven Hydrogen Arc Discharge Plasma

    E-Print Network [OSTI]

    Laulainen, J; Koivisto, H; Komppula, J; Tarvainen, O

    2015-01-01

    Photoelectron emission measurements have been performed using a filament-driven multi-cusp arc discharge volume production H^- ion source (LIISA). It has been found that photoelectron currents obtained with Al, Cu, Mo, Ta and stainless steel (SAE 304) are on the same order of magnitude. The photoelectron currents depend linearly on the discharge power. It is shown experimentally that photoelectron emission is significant only in the short wavelength range of hydrogen spectrum due to the energy dependence of the quantum efficiency. It is estimated from the measured data that the maximum photoelectron flux from plasma chamber walls is on the order of 1 A per kW of discharge power.

  18. WELDING RESEARCH -S25WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -S25WELDING JOURNAL ABSTRACT. Stress-relief cracking is a major cause of weld conventional TEM and STEM techniques. The results of this study form a basis for heat treatment and welding fabricated from 2.25Cr-1Mo steel may require welding at both the installation and fabrication stages, and in

  19. WELDING RESEARCH -s57WELDING JOURNAL

    E-Print Network [OSTI]

    Zhang, YuMing

    WELDING RESEARCH -s57WELDING JOURNAL ABSTRACT. Low heat input is typically desired for welding high welding. However, a high current, and thus a high heat input, is required to melt more wire to achieve the HAZ size, microstructure, and the hard- ness of high-strength steel ASTM A514 welded by DE

  20. CLOSURE WELD DEVELOPMENT FOR 3013 OUTER CONTAINERS

    SciTech Connect (OSTI)

    Daugherty, W.; Howard, S.; Peterson, K.; Stokes, M.

    2009-11-10

    Excess plutonium materials in the DOE complex are packaged and stored in accordance with DOE-STD-3013. This standard specifies requirements for the stabilization of such materials and subsequent packaging in dual nested seal-welded containers. Austenitic stainless steels have been selected for container fabrication. The inner 3013 container provides contamination control while the outer 3013 container is the primary containment vessel and is the focus of this paper. Each packaging site chose a process for seal welding the outer 3013 containers in accordance with its needs and expertise. The two processes chosen for weld closure were laser beam welding (LBW) and gas tungsten arc welding (GTAW). Following development efforts, each system was qualified in accordance with DOE-STD-3013 prior to production use. The 3013 outer container closure weld joint was designed to accommodate the characteristics of a laser weld. This aspect of the joint design necessitated some innovative process and equipment considerations in the application of the GTAW process. Details of the weld requirements and the development processes are presented and several potential enhancements for the GTAW system are described.

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

    SciTech Connect (OSTI)

    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)

    2011-01-17

    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.

  2. Wonder Weld

    SciTech Connect (OSTI)

    2012-01-01

    Engineers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory are using the process shown here to create a super-strong weld for the upgrade of a key component of the Lab's experimental nuclear fusion reactor.

  3. Selection of Processes for Welding Steel Rails

    E-Print Network [OSTI]

    Eagar, Thomas W.

    structure. · Particular attention is given to thermit, flash and oxyacetylene processes with some discussion for welding of steel rail. The traditional pro- cesses of thermit, oxacetylene and flash welding are well is brought to an elevated temperature, and the heat diffuses into the bulk of the metal. Thermit, electroslag

  4. Matrix penetration in the bulk:In uence of humidity: Morphological analysis of wood welding

    E-Print Network [OSTI]

    Psaltis, Demetri

    Matrix penetration in the bulk:In uence of humidity: Morphological analysis of wood welding.pichelin@b .ch Context: Wood can be welded using linear vibration welding tech- niques similar to the ones in plastic and metal industry[1] . Wood welding allows bonding strength similar to glued joints. However, due

  5. WELDING RESEARCH -s281WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -s281WELDING JOURNAL ABSTRACT. Superaustenitic stainless steel alloys can often pose difficulties dur- ing fusion welding due to the unavoidable microsegregation of Mo and tramp ele. A method of producing austenitic welds is proposed that can po- tentially circumvent these issues by de

  6. WELDING RESEARCH -s77WELDING JOURNAL

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH -s77WELDING JOURNAL ABSTRACT. The microstructure of AL- 6XN plates joined via a double-sided fric- tion stir weld has been investigated. The microstructural zones that develop during friction stir welding (FSW) reflect de- creasing strains and less severe thermal cy- cles with increasing

  7. WELDING RESEARCH SUPPLEMENT | 253-s RESEARCH/DEVELOPMENT/RESEARCH/DEVELOPMENT/RESEARCH/DEVELOPMENT/RESEARCH/DEVELOPMENT

    E-Print Network [OSTI]

    DuPont, John N.

    WELDING RESEARCH SUPPLEMENT | 253-s RESEARCH-3 welds were evalu- ated, along with composite fusion zones prepared with 20Cb-3 base metal and INCO in the chemical and process industries. Because of the high Ni content, the weld metal solidifies in the fully

  8. Neural network analysis of strength and ductility of welding alloys for high strength low

    E-Print Network [OSTI]

    Cambridge, University of

    Neural network analysis of strength and ductility of welding alloys for high strength low alloy There are considerable demands for the development of weld metals for high strength low alloy steels. To assist in meeting such demands, a neural network was trained and tested on a set of data obtained on weld metals

  9. Narrow gap laser welding

    DOE Patents [OSTI]

    Milewski, J.O.; Sklar, E.

    1998-06-02

    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.

  10. Narrow gap laser welding

    DOE Patents [OSTI]

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

    1998-01-01

    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.

  11. Review Article Timing of collision of the KohistanLadakh Arc with India

    E-Print Network [OSTI]

    Seno, Tetsuzo

    Review Article Timing of collision of the Kohistan­Ladakh Arc with India and Asia: Debateiar_774 was regarded as of Jurassic­Cretaceous age and was welded to Asia and India by Northern and Southern Sutures respectively. Formation of this arc, timings of its collisions with Asia and India, and position of collision

  12. Arc Position Sensing

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

    device. Basically, an ECL can determine positions of arcs within an electric arc furnace in real time. No other measurement technique can give this kind of information....

  13. PDC IC WELD FAILURE EVALUATION AND RESOLUTION

    SciTech Connect (OSTI)

    Korinko, P.; Howard, S.; Maxwell, D.; Fiscus, J.

    2012-04-16

    During final preparations for start of the PDCF Inner Can (IC) qualification effort, welding was performed on an automated weld system known as the PICN. During the initial weld, using a pedigree canister and plug, a weld defect was observed. The defect resulted in a hole in the sidewall of the canister, and it was observed that the plug sidewall had not been consumed. This was a new type of failure not seen during development and production of legacy Bagless Transfer Cans (FB-Line/Hanford). Therefore, a team was assembled to determine the root cause and to determine if the process could be improved. After several brain storming sessions (MS and T, R and D Engineering, PDC Project), an evaluation matrix was established to direct this effort. The matrix identified numerous activities that could be taken and then prioritized those activities. This effort was limited by both time and resources (the number of canisters and plugs available for testing was limited). A discovery process was initiated to evaluate the Vendor's IC fabrication process relative to legacy processes. There were no significant findings, however, some information regarding forging/anneal processes could not be obtained. Evaluations were conducted to compare mechanical properties of the PDC canisters relative to the legacy canisters. Some differences were identified, but mechanical properties were determined to be consistent with legacy materials. A number of process changes were also evaluated. A heat treatment procedure was established that could reduce the magnetic characteristics to levels similar to the legacy materials. An in-situ arc annealing process was developed that resulted in improved weld characteristics for test articles. Also several tack welds configurations were addressed, it was found that increasing the number of tack welds (and changing the sequence) resulted in decreased can to plug gaps and a more stable weld for test articles. Incorporating all of the process improvements for the actual can welding process, however, did not result in an improved weld geometry. Several possibilities for the lack of positive response exist, some of which are that (1) an insufficient number of test articles were welded under prototypic conditions, (2) the process was not optimized so that significant improvements were observable over the 'noise', and (3) the in-situ arc anneal closed the gap down too much so the can was unable to exhaust pressure ahead of the weld. Several operational and mechanical improvements were identified. The weld clamps were changed to a design consistent with those used in the legacy operations. A helium puff operation was eliminated; it is believed that this operation was the cause of the original weld defect. Also, timing of plug mast movement was found to correspond with weld irregularities. The timing of the movement was changed to occur during weld head travel between tacks. In the end a three sequential tack weld process followed by a pulse weld at the same current and travel speed as was used for the legacy processes was suggested for use during the IC qualification effort. Relative to legacy welds, the PDC IC weld demonstrates greater fluctuation in the region of the weld located between tack welds. However, canister weld response (canister to canister) is consistent and with the aid of the optical mapping system (for targeting the cut position) is considered adequate. DR measurements and METs show the PDC IC welds to have sufficient ligament length to ensure adequate canister pressure/impact capacity and to ensure adequate stub function. The PDC welding process has not been optimized as a result of this effort. Differences remain between the legacy BTC welds and the PDC IC weld, but these differences are not sufficient to prevent resumption of the current PDC IC qualification effort. During the PDC IC qualification effort, a total of 17 cans will be welded and a variety of tests/inspections will be performed. The extensive data collected during that qualification effort should be of a sufficient population to determ

  14. Seal welded cast iron nuclear waste container

    DOE Patents [OSTI]

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

    1987-01-01

    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.

  15. Intermetallic alloy welding wires and method for fabricating the same

    DOE Patents [OSTI]

    Santella, M.L.; Sikka, V.K.

    1996-06-11

    Welding wires for welding together intermetallic alloys of nickel aluminides, nickel-iron aluminides, iron aluminides, or titanium aluminides, and preferably including additional alloying constituents are fabricated as two-component, clad structures in which one component contains the primary alloying constituent(s) except for aluminum and the other component contains the aluminum constituent. This two-component approach for fabricating the welding wire overcomes the difficulties associated with mechanically forming welding wires from intermetallic alloys which possess high strength and limited ductilities at elevated temperatures normally employed in conventional metal working processes. The composition of the clad welding wires is readily tailored so that the welding wire composition when melted will form an alloy defined by the weld deposit which substantially corresponds to the composition of the intermetallic alloy being joined. 4 figs.

  16. Intermetallic alloy welding wires and method for fabricating the same

    DOE Patents [OSTI]

    Santella, Michael L. (Knoxville, TN); Sikka, Vinod K. (Oak Ridge, TN)

    1996-01-01

    Welding wires for welding together intermetallic alloys of nickel aluminides, nickel-iron aluminides, iron aluminides, or titanium aluminides, and preferably including additional alloying constituents are fabricated as two-component, clad structures in which one component contains the primary alloying constituent(s) except for aluminum and the other component contains the aluminum constituent. This two-component approach for fabricating the welding wire overcomes the difficulties associated with mechanically forming welding wires from intermetallic alloys which possess high strength and limited ductilities at elevated temperatures normally employed in conventional metal working processes. The composition of the clad welding wires is readily tailored so that the welding wire composition when melted will form an alloy defined by the weld deposit which substantially corresponds to the composition of the intermetallic alloy being joined.

  17. HEAT INPUT AND POST WELD HEAT TREATMENT EFFECTS ON REDUCED-ACTIVATION FERRITIC/MARTENSITIC STEEL FRICTION STIR WELDS

    SciTech Connect (OSTI)

    Tang, Wei; Chen, Gaoqiang; Chen, Jian; Yu, Xinghua; Frederick, David Alan; Feng, Zhili

    2015-01-01

    Reduced-activation ferritic/martensitic (RAFM) steels are an important class of structural materials for fusion reactor internals developed in recent years because of their improved irradiation resistance. However, they can suffer from welding induced property degradations. In this paper, a solid phase joining technology friction stir welding (FSW) was adopted to join a RAFM steel Eurofer 97 and different FSW parameters/heat input were chosen to produce welds. FSW response parameters, joint microstructures and microhardness were investigated to reveal relationships among welding heat input, weld structure characterization and mechanical properties. In general, FSW heat input results in high hardness inside the stir zone mostly due to a martensitic transformation. It is possible to produce friction stir welds similar to but not with exactly the same base metal hardness when using low power input because of other hardening mechanisms. Further, post weld heat treatment (PWHT) is a very effective way to reduce FSW stir zone hardness values.

  18. Weld solidification cracking in 304 to 204L stainless steel

    SciTech Connect (OSTI)

    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

    2010-09-15

    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.

  19. Weld solidification cracking in 304 to 304L stainless steel

    SciTech Connect (OSTI)

    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

    2010-01-01

    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.

  20. DOI: 10.1002/adem.201100211 Atomistic Simulation of the Explosion Welding Process**

    E-Print Network [OSTI]

    Nordlund, Kai

    DOI: 10.1002/adem.201100211 Atomistic Simulation of the Explosion Welding Process** By Ossi Saresoja, Antti Kuronen* and Kai Nordlund Explosive welding (EXW) is an industrial process used to join. In the process, welding occurs in a high velocity collision between metal plates, achieved by using chemical

  1. Fusion welding process

    DOE Patents [OSTI]

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

    1983-01-01

    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.

  2. Rotating arc spark plug

    DOE Patents [OSTI]

    Whealton, John H.; Tsai, Chin-Chi

    2003-05-27

    A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

  3. Comparing Laser Welding Technologies with Friction Stir Welding for Production of Aluminum Tailor-Welded Blanks

    SciTech Connect (OSTI)

    Hovanski, Yuri; Carsley, John; Carlson, Blair; Hartfield-Wunsch, Susan; Pilli, Siva Prasad

    2014-01-15

    A comparison of welding techniques was performed to determine the most effective method for producing aluminum tailor-welded blanks for high volume automotive applications. Aluminum sheet was joined with an emphasis on post weld formability, surface quality and weld speed. Comparative results from several laser based welding techniques along with friction stir welding are presented. The results of this study demonstrate a quantitative comparison of weld methodologies in preparing tailor-welded aluminum stampings for high volume production in the automotive industry. Evaluation of nearly a dozen welding variations ultimately led to down selecting a single process based on post-weld quality and performance.

  4. Arc initiation in cathodic arc plasma sources

    DOE Patents [OSTI]

    Anders, Andre (Albany, CA)

    2002-01-01

    A "triggerless" arc initiation method and apparatus is based on simply switching the arc supply voltage to the electrodes (anode and cathode). Neither a mechanical trigger electrode nor a high voltage flashover from a trigger electrode is required. A conducting path between the anode and cathode is provided, which allows a hot spot to form at a location where the path connects to the cathode. While the conductive path is eroded by the cathode spot action, plasma deposition ensures the ongoing repair of the conducting path. Arc initiation is achieved by simply applying the relatively low voltage of the arc power supply, e.g. 500 V-1 kV, with the insulator between the anode and cathode coated with a conducting layer and the current at the layer-cathode interface concentrated at one or a few contact points. The local power density at these contact points is sufficient for plasma production and thus arc initiation. A conductive surface layer, such as graphite or the material being deposited, is formed on the surface of the insulator which separates the cathode from the anode. The mechanism of plasma production (and arc initiation) is based on explosive destruction of the layer-cathode interface caused by joule heating. The current flow between the thin insulator coating and cathode occurs at only a few contact points so the current density is high.

  5. CRAD, Welding, Cutting and Brazing Assessment Plan

    Office of Energy Efficiency and Renewable Energy (EERE)

    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.

  6. EVALUATION OF CONSTANT CURRENT WELD CONTROL FOR PINCH WELDING

    SciTech Connect (OSTI)

    Korinko, P; STANLEY, S; HOWARD, H

    2005-10-11

    Modern weld controllers typically use current to control the weld process. SRS uses a legacy voltage control method. This task was undertaken to determine if the improvements in the weld control equipment could be implemented to provide improvements to the process control. The constant current mode of operation will reduce weld variability by about a factor of 4. The constant voltage welds were slightly hotter than the constant current welds of the same nominal current. The control mode did not appear to adversely affect the weld quality, but appropriate current ranges need to be established and a qualification methodology for both welding and shunt calibrations needs to be developed and documented.

  7. Dual wire welding torch and method

    DOE Patents [OSTI]

    Diez, Fernando Martinez (Peoria, IL); Stump, Kevin S. (Sherman, IL); Ludewig, Howard W. (Groveland, IL); Kilty, Alan L. (Peoria, IL); Robinson, Matthew M. (Peoria, IL); Egland, Keith M. (Peoria, IL)

    2009-04-28

    A welding torch includes a nozzle with a first welding wire guide configured to orient a first welding wire in a first welding wire orientation, and a second welding wire guide configured to orient a second welding wire in a second welding wire orientation that is non-coplanar and divergent with respect to the first welding wire orientation. A method of welding includes moving a welding torch with respect to a workpiece joint to be welded. During moving the welding torch, a first welding wire is fed through a first welding wire guide defining a first welding wire orientation and a second welding wire is fed through a second welding wire guide defining a second welding wire orientation that is divergent and non-coplanar with respect to the first welding wire orientation.

  8. Evaluation of laser welding techniques for hydrogen transmission. Final report, September 1977-November 1979

    SciTech Connect (OSTI)

    Mucci, J

    1980-05-01

    This program was established to determine the feasibility of laser beam welding as a fabrication method for hydrogen transmission and is a precursor in the effort to systematically provide the technological base necessary for large-scale, economic pipeline transmission of fuel for a hydrogen energy system. The study contributes to the technology base by establishing the effect of conventional weld processes and laser beam welding on the mechanical properties of two classes of steels in an air and high pressure gaseous hydrogen environment. Screening evaluation of the tensile, low-cycle fatigue and fracture toughness properties and metallurgical analyses provide the basis for concluding that laser beam welding of AISI 304L stainless steel and ASTM A106B carbon steel can produce weldments of comparable quality to those produced by gas-tungsten arc and electron beam welding and is at least equally compatible with 13.8 MPa (2000 psig) gaseous hydrogen environment.

  9. Electric arc saw apparatus

    DOE Patents [OSTI]

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    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.

  10. Capacitor discharge process for welding braided cable

    DOE Patents [OSTI]

    Wilson, Rick D. (Corvallis, OR)

    1995-01-01

    A capacitor discharge process for welding a braided cable formed from a plurality of individual cable strands to a solid metallic electrically conductive member comprises the steps of: (a) preparing the electrically conductive member for welding by bevelling one of its end portions while leaving an ignition projection extending outwardly from the apex of the bevel; (b) clamping the electrically conductive member in a cathode fixture; (c) connecting the electrically conductive member clamped in the cathode fixture to a capacitor bank capable of being charged to a preselected voltage value; (d) preparing the braided cable for welding by wrapping one of its end portions with a metallic sheet to form a retaining ring operable to maintain the individual strands of the braided cable in fixed position within the retaining ring; (e) clamping the braided cable and the retaining ring as a unit in an anode fixture so that the wrapped end portion of the braided cable faces the ignition projection of the electrically conductive member; and (f) moving the cathode fixture towards the anode fixture until the ignition projection of the electrically conductive member contacts the end portion of the braided cable thereby allowing the capacitor bank to discharge through the electrically conductive member and through the braided cable and causing the electrically conductive member to be welded to the braided cable via capacitor discharge action.

  11. Weld Results SUNY Stony Brook

    E-Print Network [OSTI]

    McDonald, Kirk

    Weld Results Yan Zhan SUNY Stony Brook June 13rd, 2013 1 #12;Outline · Studied Parameters · Results Analysis ­ Contours Plots For the Weld Region ­ Axial Velocity Profile at Different Locations Near the Weld ­ Plots of Turbulent Kinetic Energy and Momentum Thickness Near the Weld ­ Line Plot Goes From Inlet

  12. Lienert named American Welding Society Fellow

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

    Lienert Named American Welding Society Fellow Lienert named American Welding Society Fellow Lienert was inducted into the American Welding Society's 2012 Class of Fellows during...

  13. Electric arc saw apparatus

    DOE Patents [OSTI]

    Deichelbohrer, P.R.

    1983-08-08

    A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

  14. Effect of stainless steel weld overlay cladding on the structural integrity of flawed steel plates in bending. Series 1

    SciTech Connect (OSTI)

    Corwin, W.R.; Robinson, G.C.; Nanstad, R.K.; Merkle, J.G.; Berggren, R.G.; Goodwin, G.M.; Swain, R.L.; Owings, T.D.

    1985-04-01

    The Heavy-Section Steel Technology (HSST) Stainless Steel Cladding Evaluations were undertaken to study the interaction of stainless steel cladding on the inside surface of a reactor pressure vessel with flaws initiating and propagating in base metal. With the more recent focus of safety studies on overcooling type transients, for which the behavior of small flaws is important, stainless steel cladding may have a key role in controlling the propagation and/or arrest of propagating flaws. A complicating factor in understanding the role of stainless steel cladding in this setting is the scarcity of data on its fracture toughness as a function of radiation dose and the fabrication process. The initial phase of the HSST evaluations addresses this question by testing the response of 51-mm-thick flawed plates clad with single-wire, submerged-arc weld overlays of different toughness levels. The tests completed indicate that cladding of moderate toughness had a limited ability to enhance the structural arrest toughness of a beam in bending. The specimen design and fabrication techniques employed for this first completed series of tests resulted in flaw and specimen configurations that prevented adequate control of the stress state at pop-in of the hydrogen-charged electron-beam welds. As a result, analyses of the tests by two approximate techniques and by the ORMGEN-ADINA-ORVIRT finite-element programs were not completely consistent.

  15. Miniaturized cathodic arc plasma source

    DOE Patents [OSTI]

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

    2003-04-15

    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.

  16. Anomalous behaviour of molybdenum in steel welds

    E-Print Network [OSTI]

    Choudhary, Habib Ullah

    their applications to other areas, like steam generators and heaters. The range of applications includes chemical reactor vessels, nuclear power gener- ation components and also superheaters of steam generators. They have recently been used in hydrotreating vessels... hardening effect. Typical applications are: pres- sure vessels for transport and storage, submarines, heavy road vehicles etc. 1.2.1 The Effect of Molybdenum on Weld Metal There is a microstructural effect which is especially prominent in molybdenum...

  17. Arc Casting Intermetallic Alloy (Materials Preparation Center)

    SciTech Connect (OSTI)

    2010-01-01

    Arc casting of intermetallic (La-Ni-Sn) AB5 alloy used for metal hydride hydrogen storage. Upon solidification the Sn is partially rejected and increases in concentration in the remaining liquid. Upon completing solidification there is a great deal of internal stress in the ingot. As the ingot cools further the stress is relieved. This material was cast at the Ames Laboratorys Materials Preparation Center http://www.mpc.ameslab.gov

  18. Ion charge state fluctuations in vacuum arcs

    E-Print Network [OSTI]

    Anders, Andre; Fukuda, Kentaro; Yushkov, Georgy Yu

    2004-01-01

    known that cathodic vacuum arc plasmas contain multiple ionfunctions [16]. The arc plasma is known to be “noisy,” thatcondensation of cathodic arc plasma. They are also used as

  19. Friction stir welding tool

    DOE Patents [OSTI]

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

    2008-04-15

    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.

  20. Investigation of electromagnetic welding

    E-Print Network [OSTI]

    Pressl, Daniel G. (Daniel Gerd)

    2009-01-01

    We propose several methodologies to study and optimize the electromagnetic process for Electromagnetic Forming (EMF) and Welding (EMW), thereby lowering the necessary process energy up to a factor of three and lengthening ...

  1. Concurrent ultrasonic weld evaluation system

    DOE Patents [OSTI]

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

    1985-09-04

    A system for concurrent, non-destructive evaluation of partially completed welds for use in conjunction with an automated welder. 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.

  2. Concurrent ultrasonic weld evaluation system

    DOE Patents [OSTI]

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

    1987-12-15

    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.

  3. Comparison Between Keyhole Weld Model and Laser Welding Experiments...

    Office of Scientific and Technical Information (OSTI)

    A series of laser welds were performed using a high-power diode-pumped continuous-wave Nd:YAG laser welder. In a previous study, the experimental results of those welds were...

  4. Chopping effect observed at cathodic arc initiation

    E-Print Network [OSTI]

    Anders, Andre

    2000-01-01

    generation by vacuum arc plasma guns,” Rev. Sci. Instrum. ,probe L L SCR C C D I arc plasma source and filter cathode Rto IEEE Trans. Plasma Science Cathodic arcs or “vacuum” arcs

  5. Certification of a weld produced by friction stir welding

    DOE Patents [OSTI]

    Obaditch, Chris; Grant, Glenn J

    2013-10-01

    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.

  6. An investigation of the dynamic separation of spot welds under plane tensile pulses

    SciTech Connect (OSTI)

    Ma, Bohan; Fan, Chunlei; Chen, Danian Wang, Huanran; Zhou, Fenghua

    2014-08-07

    We performed ultra-high-speed tests for purely opening spot welds using plane tensile pulses. A gun system generated a parallel impact of a projectile plate onto a welded plate. Induced by the interactions of the release waves, the welded plate opened purely under the plane tensile pulses. We used the laser velocity interferometer system for any reflector to measure the velocity histories of the free surfaces of the free part and the spot weld of the welded plate. We then used a scanning electron microscope to investigate the recovered welded plates. We found that the interfacial failure mode was mainly a brittle fracture and the cracks propagated through the spot nugget, while the partial interfacial failure mode was a mixed fracture comprised ductile fracture and brittle fracture. We used the measured velocity histories to evaluate the tension stresses in the free part and the spot weld of the welded plate by applying the characteristic theory. We also discussed the different constitutive behaviors of the metals under plane shock loading and under uniaxial split Hopkinson pressure bar tests. We then compared the numerically simulated velocity histories of the free surfaces of the free part and the spot weld of the welded plate with the measured results. The numerical simulations made use of the fracture stress criteria, and then the computed fracture modes of the tests were compared with the recovered results.

  7. Measurement of Plastic Strain Distribution in Dissimilar Metal...

    Office of Scientific and Technical Information (OSTI)

    Measurement of Plastic Strain Distribution in Dissimilar Metal Weld by Micro-hardness Mapping Citation Details In-Document Search Title: Measurement of Plastic Strain Distribution...

  8. Robotic Welding and Inspection System

    SciTech Connect (OSTI)

    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

    2008-06-01

    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.

  9. Friction stir welding tool and process for welding dissimilar materials

    DOE Patents [OSTI]

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

    2013-05-07

    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.

  10. Method and apparatus for assessing weld quality

    DOE Patents [OSTI]

    Smartt, Herschel B. (Idaho Falls, ID); Kenney, Kevin L. (Idaho Falls, ID); Johnson, John A. (Idaho Falls, ID); Carlson, Nancy M. (Idaho Falls, ID); Clark, Denis E. (Idaho Falls, ID); Taylor, Paul L. (Boise, ID); Reutzel, Edward W. (State College, PA)

    2001-01-01

    Apparatus for determining a quality of a weld produced by a welding device according to the present invention includes a sensor operatively associated with the welding device. The sensor is responsive to at least one welding process parameter during a welding process and produces a welding process parameter signal that relates to the at least one welding process parameter. A computer connected to the sensor is responsive to the welding process parameter signal produced by the sensor. A user interface operatively associated with the computer allows a user to select a desired welding process. The computer processes the welding process parameter signal produced by the sensor in accordance with one of a constant voltage algorithm, a short duration weld algorithm or a pulsed current analysis module depending on the desired welding process selected by the user. The computer produces output data indicative of the quality of the weld.

  11. Masatsu kakuhan setsugo "Friction Stir Welding Complete aspects of FSW" Japan Welding Society

    E-Print Network [OSTI]

    Cambridge, University of

    Masatsu kakuhan setsugo ­ "Friction Stir Welding ­ Complete aspects of FSW" Japan Welding Society years ago that the Friction Stir Welding (FSW) method was proposed by TWI. Because FSW is a solid state welding method, the peak temperature reached during FSW welding is lower than the traditional welding

  12. Matrix phased array (MPA) imaging technology for resistance spot welds

    SciTech Connect (OSTI)

    Na, Jeong K.; Gleeson, Sean T. [Edison Welding Institute, 1250 Arthur E. Adams Drive, Columbus, OH 43221 (United States)

    2014-02-18

    A three-dimensional MPA probe has been incorporated with a high speed phased array electronic board to visualize nugget images of resistance spot welds. The primary application area of this battery operated portable MPA ultrasonic imaging system is in the automotive industry which a conventional destructive testing process is commonly adopted to check the quality of resistance spot welds in auto bodies. Considering an average of five-thousand spot welds in a medium size passenger vehicle, the amount of time and effort given to popping the welds and measuring nugget size are immeasurable in addition to the millions of dollars' worth of scrap metals recycled per plant per year. This wasteful labor intensive destructive testing process has become less reliable as auto body sheet metal has transitioned from thick and heavy mild steels to thin and light high strength steels. Consequently, the necessity of developing a non-destructive inspection methodology has become inevitable. In this paper, the fundamental aspects of the current 3-D probe design, data acquisition algorithms, and weld nugget imaging process are discussed.

  13. Nozzle Weld Beads Stony Brook University

    E-Print Network [OSTI]

    McDonald, Kirk

    Nozzle Weld Beads Yan Zhan Stony Brook University 12/27/2011 #12;Location of interests: welded)Fig. 1 Hg nozzle assembly Location of the Interested Weld #12;Surface Topology of the Weld Bead is a crude assumption ­ Start with a symmetric torus geometry · Circular axis is the nominal line of the weld

  14. Method for welding chromium molybdenum steels

    DOE Patents [OSTI]

    Sikka, Vinod K. (Clinton, TN)

    1986-01-01

    Chromium-molybdenum steels exhibit a weakening after welding in an area adjacent to the weld. This invention is an improved method for welding to eliminate the weakness by subjecting normalized steel to a partial temper prior to welding and subsequently fully tempering the welded article for optimum strength and ductility.

  15. Self-sputtering far above the runaway threshold: an extraordinary metal ion generator

    E-Print Network [OSTI]

    Andersson, Joakim

    2009-01-01

    an extraordinary metal ion generator  Joakim Andersson andan extraordinarily prolific generator of useable metal ions.Among the most prolific generators of ions are cathodic arc

  16. Controlling electrode gap during vacuum arc remelting at low melting current

    DOE Patents [OSTI]

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

    1997-04-15

    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.

  17. Controlling electrode gap during vacuum arc remelting at low melting current

    DOE Patents [OSTI]

    Williamson, Rodney L. (Albuquerque, NM); Zanner, Frank J. (Sandia Park, NM); Grose, Stephen M. (Glenwood, WV)

    1997-01-01

    An apparatus and method 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.

  18. Effect of oxygen on weld shape and crystallographic orientation of duplex stainless steel weld using advanced A-TIG (AA-TIG) welding method

    SciTech Connect (OSTI)

    Zou, Ying, E-mail: yingzou@jwri.osaka-u.ac.jp; Ueji, Rintaro; Fujii, Hidetoshi

    2014-05-01

    The double-shielded advanced A-TIG (AA-TIG) welding method was adopted in this study for the welding of the SUS329J4L duplex stainless steel with the shielding gases of different oxygen content levels. The oxygen content in the shielding gas was controlled by altering the oxygen content in the outer layer gas, while the inner layer remained pure argon to suppress oxidation on the tungsten electrode. As a result, a deep weld penetration was obtained due to the dissolution of oxygen into the weld metals. Additionally, the microstructure of the weld metal was changed by the dissolution of oxygen. The austenite phase at the ferrite grain boundary followed a Kurdjumov–Sachs (K–S) orientation relationship with the ferrite matrix phase at any oxide content. On the other hand, the orientation relationship between the intragranular austenite phase and the ferrite matrix phase exhibited different patterns under different oxygen content levels. When there was little oxide in the fusion zone, only a limited part of the intragranular austenite phase and the ferrite matrix phase followed the K–S orientation relationship. With the increase of the oxide, the correspondence of the K–S relationship increased and fit very well in the 2.5% O{sub 2} shielded sample. The investigation of this phenomenon was carried out along with the nucleation mechanisms of the intragranular austenite phases. - Highlights: • Weld penetration increased with the increase of the oxygen content. • Average diameter and number density of oxide were changed by the oxygen content. • K-S relationship of Widmanstätten austenite/ferrite wasn’t varied by oxide. • Orientation relationship of intragranular austenite/ferrite was varied by oxide.

  19. The Magnetite Crisis in the Evolution of Arc-related Magmas and the Initial

    E-Print Network [OSTI]

    Lee, Cin-Ty Aeolus

    and back-arc magma series is their association with ores of the rare, but economically important metals Au of these metals is not straightforward. For Au, one of the rarest metals on Earth, with a primitive mantle RESEARCH SCHOOL OF EARTH SCIENCES, AUSTRALIAN NATIONAL UNIVERSITY, CANBERRA, ACT 0200, AUSTRALIA RECEIVED

  20. Shell Hoop Prestress Generated by Welding

    E-Print Network [OSTI]

    Meuser, R.B.

    2011-01-01

    can be generated by the welding process. The data are notagainst the yoke for welding. TEST SETUP Annealed Type 304in two passes using TIG welding. After strain measurements

  1. Arc Position Sensing Technology

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D SFederal8823 Revision 02 (CRACApril JanuaryAps_notifyArc

  2. Cathodic Arc Plasma Deposition

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report: Achievements ofCOMPOSITION OF VAPORS FROM BOILING NITRIC ACIDCathodic Arc

  3. Arc Position Sensing Technology

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

    (VAR) furnaces for industries that use specialty metals such as nickel, titanium, and zirconium. The technology could be used to help produce materials with stronger chemical and...

  4. BEHAVIOR OF METALLIC INCLUSIONS IN URANIUM DIOXIDE

    E-Print Network [OSTI]

    Yang, Rosa L.

    2013-01-01

    nuclear fuels irradiated to high burnup metallic fissionoxide fuel and observed trails behind metallic 1on thesemetallic fission products arc found attached to of the central void of Lf\\1FBR fuels,

  5. Resistance spot welding of ultra-fine grained steel sheets produced by constrained groove pressing: Optimization and characterization

    SciTech Connect (OSTI)

    Khodabakhshi, F.; Kazeminezhad, M., E-mail: mkazemi@sharif.edu; Kokabi, A.H.

    2012-07-15

    Constrained groove pressing as a severe plastic deformation method is utilized to produce ultra-fine grained low carbon steel sheets. The ultra-fine grained sheets are joined via resistance spot welding process and the characteristics of spot welds are investigated. Resistance spot welding process is optimized for welding of the sheets with different severe deformations and their results are compared with those of as-received samples. The effects of failure mode and expulsion on the performance of ultra-fine grained sheet spot welds have been investigated in the present paper and the welding current and time of resistance spot welding process according to these subjects are optimized. Failure mode and failure load obtained in tensile-shear test, microhardness, X-ray diffraction, transmission electron microscope and scanning electron microscope images have been used to describe the performance of spot welds. The region between interfacial to pullout mode transition and expulsion limit is defined as the optimum welding condition. The results show that optimum welding parameters (welding current and welding time) for ultra-fine grained sheets are shifted to lower values with respect to those for as-received specimens. In ultra-fine grained sheets, one new region is formed named recrystallized zone in addition to fusion zone, heat affected zone and base metal. It is shown that microstructures of different zones in ultra-fine grained sheets are finer than those of as-received sheets. - Highlights: Black-Right-Pointing-Pointer Resistance spot welding process is optimized for joining of UFG steel sheets. Black-Right-Pointing-Pointer Optimum welding current and time are decreased with increasing the CGP pass number. Black-Right-Pointing-Pointer Microhardness at BM, HAZ, FZ and recrystallized zone is enhanced due to CGP.

  6. Lienert named American Welding Society Fellow

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

    Lienert named American Welding Society Fellow November 29, 2012 Thomas J. Lienert of the Lab's Metallurgy group was inducted into the American Welding Society's 2012 Class of...

  7. Cathodic Vacuum Arc Plasma of Thallium

    E-Print Network [OSTI]

    Yushkov, Georgy Yu.; Anders, Andre

    2006-01-01

    P. J. Martin, Handbook of Vacuum Arc Science and Technology.charge state distributions of vacuum arc plasmas: The originand the broadening of vacuum-arc ion charge state

  8. Cathodic Vacuum Arc Plasma of Thallium

    E-Print Network [OSTI]

    Yushkov, Georgy Yu.; Anders, Andre

    2006-01-01

    distributions of vacuum arc plasmas: The origin of species,"spectrum for thallium arc plasma, as measured for 400 A,and thallium vacuum arc plasmas. For comparison, the data

  9. Robotic weld overlay coatings for erosion control. Final technical progress report, July 1992--July 1995

    SciTech Connect (OSTI)

    Levin, B.F.; DuPont, J.N.; Marder, A.R.

    1995-10-15

    The erosion behavior of weld overlay coatings has been studied. Eleven weld overlay alloys were deposited on 1018 steel substrates using the plasma arc welding process and erosion tested at 400{degrees}C at 90{degrees} and 30{degrees} particle impact angles. The microstructure of each coating was characterized before erosion testing. A relative ranking of the coatings erosion resistance was developed by determining the steady state erosion rates. Ultimet, Inconel-625, and 316L SS coatings showed the best erosion resistance at both impact angles. It was found that weld overlays that exhibit good abrasion resistance did not show good erosion resistance. Erosion tests were also performed for selected wrought materials with chemical composition similar to weld overlays. Eroded surfaces of the wrought and weld alloys were examined by Scanning Electron Microscopy (SEM). Microhardness tests were performed on the eroded samples below the erosion surface to determine size of the plastically deformed region. It was found that one group of coatings experienced significant plastic deformation as a result of erosion while the other did not. It was also established that, in the steady state erosion regime, the size of the plastically deformed region is constant.

  10. Graphite electrode DC arc furnace. Innovative technology summary report

    SciTech Connect (OSTI)

    1999-05-01

    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.

  11. Arc fault detection system

    DOE Patents [OSTI]

    Jha, Kamal N. (Bethel Park, PA)

    1999-01-01

    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.

  12. Arc fault detection system

    DOE Patents [OSTI]

    Jha, K.N.

    1999-05-18

    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. 1 fig.

  13. Progress Report for Diffusion Welding of the NGNP Process Application Heat Exchangers

    SciTech Connect (OSTI)

    R.E. Mizia; D.E. Clark; M.V. Glazoff; T.E. Lister; T.L. Trowbridge

    2011-04-01

    The NGNP Project is currently investigating the use of metallic, diffusion welded, compact heat exchangers to transfer heat from the primary (reactor side) heat transport system to the secondary heat transport system. The intermediate heat exchanger will transfer this heat to downstream applications such as hydrogen production, process heat, and electricity generation. The channeled plates that make up the heat transfer surfaces of the intermediate heat exchanger will have to be assembled into an array by diffusion welding.

  14. CARBON DIFFUSION ACROSS DISSIMILAR STEEL WELDS

    E-Print Network [OSTI]

    Cambridge, University of

    CARBON DIFFUSION ACROSS DISSIMILAR STEEL WELDS By Julia Margaret Race St. John's College, Cambridge. 111 #12;#12;ABSTRACT Dissimilar steel welds are used extensively in the power generation industry to the high alloy side of the weld. This leaves an area on one side of the weld denuded of carbon

  15. Assessing Exposures to Particulate Matter and Manganese in Welding Fumes

    E-Print Network [OSTI]

    LIU, SA

    2010-01-01

    465.   Sapp ME.  A History of Welding: from Hepheastus to whistoryfolder/welding/index.html.   Saric M, Markicevic, be retrieved from American Welding Society publications. The

  16. Hydrologic Modeling with Arc Hydro Tools 1 Copyright 2007 ESRI. All rights reserved. Arc Hydro

    E-Print Network [OSTI]

    Slatton, Clint

    Hydrologic Modeling with Arc Hydro Tools 1 Copyright © 2007 ESRI. All rights reserved. Arc Hydro Arc Hydro: GIS in Water Resources Seminar/Workshop Gainesville, Florida ­ November 15, 2007 Christine Dartiguenave, ESRI inc. cdartiguenave@esri.com #12;Hydrologic Modeling with Arc Hydro Tools 2 2Arc Hydro

  17. Laser welding of fused quartz

    DOE Patents [OSTI]

    Piltch, Martin S.; Carpenter, Robert W.; Archer, III, McIlwaine

    2003-06-10

    Refractory materials, such as fused quartz plates and rods are welded using a heat source, such as a high power continuous wave carbon dioxide laser. The radiation is optimized through a process of varying the power, the focus, and the feed rates of the laser such that full penetration welds may be accomplished. The process of optimization varies the characteristic wavelengths of the laser until the radiation is almost completely absorbed by the refractory material, thereby leading to a very rapid heating of the material to the melting point. This optimization naturally occurs when a carbon dioxide laser is used to weld quartz. As such this method of quartz welding creates a minimum sized heat-affected zone. Furthermore, the welding apparatus and process requires a ventilation system to carry away the silicon oxides that are produced during the welding process to avoid the deposition of the silicon oxides on the surface of the quartz plates or the contamination of the welds with the silicon oxides.

  18. Characterization of monitor for laser welding.

    SciTech Connect (OSTI)

    Leong, K. H.; Hunter, B. V

    2002-05-15

    This patent-pending robust on-line weld process monitor developed by Argonne National Laboratory is capable of non-intrusively sensing weld surface changes, weld penetration, occurrence of weld spatter, direction of motion of workpiece relative to cover gas flow, and presence of surface impurities like oil on the workpiece. The development of the weld monitor took into account the constraints and operating environment of the factory floor in addition to monitoring needs for quality assurance. The non-intrusive weld monitor is rugged and simple to use, does not require power to operate, is weld spatter protected and low cost. This process monitor is available as a stand-alone monitor with laser pointing suitable as an inexpensive addition to an existing processing system. For constrained configurations, the monitor can be easily integrated into an existing optic module resulting in through-the-optic viewing. The stand-alone monitor's flexibility is suitable for test and evaluation or research and development applications where flexibility in pointing or change in optics is required. A photograph of the monitor is shown in Figure 1. The reproducibility of the monitor's signal output will depend on the accuracy and repeatability in aiming. Laser aiming that comes with the monitor offers the best overall accuracy and ease. Costs can be reduced further with conventional gunsights with loss in accuracy and ease. The reproducibility of the monitor's output will depend on the field of view, the aiming method and the capability to manually aim and lock in position. In practice, even with laser aiming, the accuracy will be compromised by the mechanical system used to allow for aiming adjustments. 10 to 20% changes may be result from using a flexible connector. Improved reproducibility can be obtained at the expense of time taken to aim accurately. The integrated version of the monitor is recommended for process operations. This integrated monitor is available as an option on Spawr Industries reflective optics for high power laser beams or as a modification to the user's beam delivery optics. The advantage of the integrated design is that the monitor is pre-aimed and does not suffer from bumping and space constraints. Excellent reproducibility of the data can then be obtained. Both versions of the monitor are supplied with a BNC connector for detecting the voltage output of the sensor. The standard sensor is optimized for the monitoring of ferrous or steel alloys and other metals that have similar properties. Sensitivity to changes in penetration of < 0.05 mm can be expected. Monitoring of aluminum alloys will require a different sensor that is available as an option. A gas connection is also supplied for the clean gas purge to maintain the cleanliness of the window of the sensor. The gas (air or nitrogen) supplied should be oil and particle free to prevent fogging of the detector window.

  19. Can surface cracks and unipolar arcs explain breakdown and gradient limits?

    SciTech Connect (OSTI)

    Insepov, Zeke; Norem, Jim

    2013-01-15

    The authors argue that the physics of unipolar arcs and surface cracks can help understand rf breakdown and vacuum arc data. They outline a model of the basic mechanisms involved in breakdown and explore how the physics of unipolar arcs and cracks can simplify the picture of breakdown and gradient limits in accelerators, tokamaks as well as laser ablation, micrometeorites, and other applications. Cracks are commonly seen in SEM images of arc damage and they are produced as the liquid metal cools. They can produce the required field enhancements to explain field emission data and can produce mechanical failure of the surface that would trigger breakdown events. Unipolar arcs can produce currents sufficient to short out rf structures, and can cause the sort of damage seen in SEM images. They should be unstable, and possibly self-quenching, as seen in optical fluctuations and surface damage. The authors describe some details and consider the predictions of this simple model.

  20. Integrity assessment of the ferritic / austenitic dissimilar weld joint between intermediate heat exchanger and steam generator in fast reactor

    SciTech Connect (OSTI)

    Jayakumar, T.; Laha, K.; Chandravathi, K. S.; Parameswaran, P.; Goyal, S.; Kumar, J. G.; Mathew, M. D.

    2012-07-01

    Integrity of the modified 9Cr-1Mo / alloy 800 dissimilar joint welded with Inconel 182 electrodes has been assessed under creep condition based on the detailed analysis of microstructure and stress distribution across the joint by finite element analysis. A hardness peak at the ferritic / austenitic weld interface and a hardness trough at the inter-critical heat affected zone (HAZ) in ferritic base metal developed. Un-tempered martensite was found at the ferritic / austenitic weld interface to impart high hardness in it; whereas annealing of martensitic structure of modified 9Cr-1Mo steel by inter-critical heating during welding thermal cycle resulted in hardness tough in the inter-critical HAZ. Creep tests were carried out on the joint and ferritic steel base metal at 823 K over a stress range of 160-320 MPa. The joint possessed lower creep rupture strength than its ferritic steel base metal. Failure of the joint at relatively lower stresses occurred at the ferritic / austenitic weld interface; whereas it occurred at inter-critical region of HAZ at moderate stresses. Cavity nucleation associated with the weld interface particles led to premature failure of the joint. Finite element analysis of stress distribution across the weld joint considering the micro-mechanical strength inhomogeneity across it revealed higher von-Mises and principal stresses at the weld interface. These stresses induced preferential creep cavitation at the weld interface. Role of precipitate in enhancing creep cavitation at the weld interface has been elucidated based on the FE analysis of stress distribution across it. (authors)

  1. Assessing Exposures to Particulate Matter and Manganese in Welding Fumes

    E-Print Network [OSTI]

    LIU, SA

    2010-01-01

    less hazardous compared to MIG welding, these areas as wellareas where high concentrations occurred; 3) although resistance welding is considered less hazardoushazardous welding operations such as resistance welding should also be effectively controlled. Those who work in areas

  2. Assessing Exposures to Particulate Matter and Manganese in Welding Fumes

    E-Print Network [OSTI]

    LIU, SA

    2010-01-01

    nickel and manganese in shipyard welding fumes.  Welding on weld fume exposures in a shipyard confined space welding 1: Manufacturing 2: Shipyard 3: Railroad 4: Automobile 0:

  3. Geochemical tracers of processes affecting the formation of seafloor hydrothermal fluids and deposits in the Manus back-arc basin

    E-Print Network [OSTI]

    Craddock, Paul R

    2009-01-01

    Systematic differences in trace element compositions (rare earth element (REE), heavy metal, metalloid concentrations) of seafloor vent fluids and related deposits from hydrothermal systems in the Manus back-arc basin ...

  4. Pseudo ribbon metal ion beam source

    SciTech Connect (OSTI)

    Stepanov, Igor B. Ryabchikov, Alexander I.; Sivin, Denis O.; Verigin, Dan A.

    2014-02-15

    The paper describes high broad metal ion source based on dc macroparticle filtered vacuum arc plasma generation with the dc ion-beam extraction. The possibility of formation of pseudo ribbon beam of metal ions with the parameters: ion beam length 0.6 m, ion current up to 0.2 A, accelerating voltage 40 kV, and ion energy up to 160 kV has been demonstrated. The pseudo ribbon ion beam is formed from dc vacuum arc plasma. The results of investigation of the vacuum arc evaporator ion-emission properties are presented. The influence of magnetic field strength near the cathode surface on the arc spot movement and ion-emission properties of vacuum-arc discharge for different cathode materials are determined. It was shown that vacuum-arc discharge stability can be reached when the magnetic field strength ranges from 40 to 70 G on the cathode surface.

  5. J. Haidar ) Rhee Kannatey-Asibu )

    E-Print Network [OSTI]

    , "Plasma diagnos- tics in gas metal arc welding by optical emission spec- troscopy", , J. Phys. D tungsten arc welding", , J. Appl. Phys p . ) Nemchinsky V A, "The effect of the type of plasma gas ) Murphy A B, "Metal vapour in atmospheric-pressure arcs", , J. Phys. D ) Murphy A B, "The effects of metal

  6. IOP PUBLISHING PLASMA SOURCES SCIENCE AND TECHNOLOGY Plasma Sources Sci. Technol. 16 (2007) 832838 doi:10.1088/0963-0252/16/4/019

    E-Print Network [OSTI]

    2007-01-01

    .iop.org/PSST/16/832 Abstract We report on investigations of gas metal arc welding plasma operated in pure argon increases while approaching the core of the plasma in the spray-arc mode, a drop in the electron temperature, a liquid, a gas and a plasma interact as an electrode, an arc, molten metal and a base metal. The welding

  7. The role of electroplated coatings in metal joining

    SciTech Connect (OSTI)

    Dini, J.W. [Lawrence Livermore National Lab., CA (United States)

    1996-05-01

    Electroplated and electroless coatings often play an important role in soldering, brazing, and welding operations. Thin deposits applied to critical surfaces before the joining operations can provide the difference between success and failure. Diffusion welding applications sometimes require coatings to help promote joining. For some applications, electroplating by itself can be used to join metals that cannot be welded or brazed because of metallurgical incompatibility. The use of electroplated coatings for these various joining applications is reviewed here.

  8. Cathodic Arc Deposition of Copper Oxide Thin Films

    E-Print Network [OSTI]

    MacGill, R.A.

    2011-01-01

    compatibility. A cathodic arc plasma source with a copperon operating a cathodic arc plasma source with a copperdeposited using a cathodic arc plasma source with a copper

  9. Ion energy distribution functions of vacuum arc plasmas

    E-Print Network [OSTI]

    Byon, Eungsun; Anders, Andre

    2002-01-01

    functions of vacuum arc plasmas Eungsun Byon and Andréfunctions of vacuum arc plasmas Eungsun Byon and Andréenergies of vacuum arc plasmas 1-7 because these energies

  10. The fractal nature of vacuum arc cathode spots

    E-Print Network [OSTI]

    Anders, Andre

    2005-01-01

    functions of vacuum arc plasmas," J. Appl. Phys. , vol. 93,macroparticles in vacuum arc plasmas," in preparation, 2005.A. Anders, Cathodic Arc Plasma Deposition: From Fractal

  11. Cathodic Arcs: Fractal Voltage and Cohesive Energy Rule

    E-Print Network [OSTI]

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

    2005-01-01

    Applications of Vacuum-Arc-Produced Plasma, Ion and Electronparameters of cathodic arc plasma, many researches decidedof a coaxial cathodic arc plasma source, and analyzing the

  12. Physics of arcing, and implications to sputter deposition

    E-Print Network [OSTI]

    Anders, Andre

    2005-01-01

    A. Anders, Cathodic Arc Plasma Deposition: From FractalApplications of Vacuum-Arc-Produced Plasma, Ion and Electronstandard) textbooks on plasmas [1], arcs are introduced as

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

    SciTech Connect (OSTI)

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

    2011-06-23

    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.

  14. Investigation on the Interface Morphologies of Explosive Welding of Inconel 625 to Steel A516 Plates

    SciTech Connect (OSTI)

    Mousavi, S. A. A. Akbari; Zareie, H. R. [School of Metallurgy and Materials Engineering, University College of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

    2011-01-17

    The purpose of this study is to produce composite plates by explosive cladding process. This is a process in which the controlled energy of explosives is used to create a metallic bond between two similar or dissimilar materials. The welding conditions were tailored through parallel geometry route with different operational parameters. In this investigation, a two-pronged study was adopted to establish the conditions required for producing successful solid state welding: (a) Analytical calculations to determine the weldability domain or welding window; (b) Metallurgical investigations of explosive welding experiments carried out under different explosive ratios to produce both wavy and straight interfaces. The analytical calculations confirm the experimental results. Optical microscopy studies show that a transition from a smooth to wavy interface occurs with an increase in explosive ratio. SEM studies show that the interface was outlined by characteristic sharp transition between two materials.

  15. The effect of travel speed on thermal response in CO{sub 2} laser welding of small electronic components

    SciTech Connect (OSTI)

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

    1995-02-01

    A comprehensive three-dimensional numerical investigation of the effect of beat source travel speed on temperatures and resulting thermal stresses was performed for CO{sub 2}-laser welding. The test specimen was a small thermal battery header containing several stress-sensitive glass-to-metal seals surrounding the electrical connections and a temperature sensitive ignitor located under the header near the center. Predictions of the thermal stresses and temperatures in the battery header were made for several travel speeds of the laser. The travel speeds examined ranged from 10mm/sec to 50mm/sec. The results indicate that faster weld speeds result in lower temperatures and stresses for the same size weld. This is because the higher speed welds are more efficient, requiring less energy to produce a given weld. Less energy absorbed by the workpiece results in lower temperatures, which results in lower stresses.

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

    SciTech Connect (OSTI)

    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)

    2012-12-15

    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.

  17. Automatic monitoring of vibration welding equipment

    DOE Patents [OSTI]

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

    2014-10-14

    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.

  18. Reducing ion beam noise of vacuum arc ion sources

    E-Print Network [OSTI]

    Anders, Andre; Hollinger, Ralph

    2001-01-01

    in the expanding vacuum arc plasma and operating in the ion3 Schematic of the vacuum arc plasma generator (arc cathodeUnfortunately, vacuum arc plasmas are rapidly fluctuating

  19. Pre-resistance-welding resistance check

    DOE Patents [OSTI]

    Destefan, Dennis E. (Broomfield, CO); Stompro, David A. (Idaho Falls, ID)

    1991-01-01

    A preweld resistance check for resistance welding machines uses an open circuited measurement to determine the welding machine resistance, a closed circuit measurement to determine the parallel resistance of a workpiece set and the machine, and a calculation to determine the resistance of the workpiece set. Any variation in workpiece set or machine resistance is an indication that the weld may be different from a control weld.

  20. Using Arc Marine in ArcGIS 10 Tutorial for Beginners

    E-Print Network [OSTI]

    Wright, Dawn Jeannine

    Using Arc Marine in ArcGIS 10 Tutorial for Beginners Introduction Arc Marine (or the ArcGIS Marine Data Model - MDM), is a geodatabase model tailored specifically for the marine GIS community. Created by researchers from Oregon State University, Duke

  1. ON THE WELDED TUBE MAP BENJAMIN AUDOUX

    E-Print Network [OSTI]

    Audoux, Benjamin

    ON THE WELDED TUBE MAP BENJAMIN AUDOUX Abstract. This paper investigates the so-called Tube map which connects welded knots, that is a quotient of the virtual knot theory, to ribbon torus-knots with a given filling are in one-to-one correspondence with welded knots before quo- tient under classical

  2. Components of the Creep Strength of Welds

    E-Print Network [OSTI]

    Cambridge, University of

    Components of the Creep Strength of Welds M. Murugananth and H.K.D.H. Bhadeshia Department://www.msm.cam.ac.uk ABSTRACT Modern power plant steels and welding alloys, designed to resist creep deforma- tion at high in the sense that it covers all common ferritic steels and welding alloys of the type used in the construc

  3. Contamination and solid state welds.

    SciTech Connect (OSTI)

    Mills, Bernice E.

    2007-05-01

    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.

  4. Arc$c Climate Dynamics James Overland

    E-Print Network [OSTI]

    · Carbon Chemistry- Mathis, Evans, Cross · Pacific Ecosystems- Stabeno, Moore, Mordy than in other regions of the globe (Arc%c Amplifica%on) Arc partnerships Contributed to wri$ng of the NOAA Arc%c Vision and Strategy Plan Part

  5. Simulation of Carbon Nanotube Welding through Ar bombardment

    E-Print Network [OSTI]

    Kucukkal, Mustafa U

    2014-01-01

    Single-walled carbon nanotubes show promise as nanoscale transistors, for nanocomputing applications. This use will require appropriate methods for creating electrical connections between distinct nanotubes, analogous to welding of metallic wires at larger length scales, but methods for performing nanoscale chemical welding are not yet sufficiently understood. This study examined the effect of Ar bombardment on the junction of two crossed single-walled carbon nanotubes, to understand the value and limitations of this method for generating connections between nanotubes. A geometric criterion was used to assess the quality of the junctions formed, with the goal of identifying the most productive conditions for experimental ion bombardment. In particular, the effects of nanotube chirality, Ar impact kinetic energy, impact particle flux and fluence, and annealing temperature were considered. The most productive bombardment conditions, leading to the most crosslinking of the tubes with the smallest loss of graphit...

  6. Journal of Pressure Vessel Technology, Vol. 131, 2009, 041401 The Effects of Filler Metal Transformation Temperature on Residual Stresses in a

    E-Print Network [OSTI]

    Cambridge, University of

    be adjusted to engineer the residual stress distribution in a bainitic-martensitic steel weld has been Transformation Temperature on Residual Stresses in a High Strength Steel Weld J. A. Francis School of Materials on structural integrity. Here the extent to which the martensite-start temperature of the weld filler metal can

  7. Intraluminal tissue welding for anastomosis

    DOE Patents [OSTI]

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

    1998-10-27

    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.

  8. Intraluminal tissue welding for anastomosis

    DOE Patents [OSTI]

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

    1998-10-27

    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.

  9. Vacuum Arc Ion Sources: Recent Developments and Applications

    SciTech Connect (OSTI)

    Brown, Ian; Oks, Efim

    2005-05-01

    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.

  10. Optical penetration sensor for pulsed laser welding

    DOE Patents [OSTI]

    Essien, Marcelino (Albuquerque, NM); Keicher, David M. (Albuquerque, NM); Schlienger, M. Eric (Albuquerque, NM); Jellison, James L. (Albuquerque, NM)

    2000-01-01

    An apparatus and method for determining the penetration of the weld pool created from pulsed laser welding and more particularly to an apparatus and method of utilizing an optical technique to monitor the weld vaporization plume velocity to determine the depth of penetration. A light source directs a beam through a vaporization plume above a weld pool, wherein the plume changes the intensity of the beam, allowing determination of the velocity of the plume. From the velocity of the plume, the depth of the weld is determined.

  11. Shimmed electron beam welding process

    DOE Patents [OSTI]

    Feng, Ganjiang (Clifton Park, NY); Nowak, Daniel Anthony (Alplaus, NY); Murphy, John Thomas (Niskayuna, NY)

    2002-01-01

    A modified electron beam welding process effects welding of joints between superalloy materials by inserting a weldable shim in the joint and heating the superalloy materials with an electron beam. The process insures a full penetration of joints with a consistent percentage of filler material and thereby improves fatigue life of the joint by three to four times as compared with the prior art. The process also allows variable shim thickness and joint fit-up gaps to provide increased flexibility for manufacturing when joining complex airfoil structures and the like.

  12. Characterization of arcs in frequency domain

    SciTech Connect (OSTI)

    D'Inca, R.; Siegl, G.; Faugel, H.; Braun, F.; Eckert, B.; Bobkov, V.; El Khaldi, M.; Noterdaeme, J.-M.

    2009-11-26

    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)

  13. The evolution of ion charge states in cathodic vacuum arc plasmas: a review

    SciTech Connect (OSTI)

    Anders, Andre

    2011-12-18

    Cathodic vacuum arc plasmas are known to contain multiply charged ions. 20 years after “Pressure Ionization: its role in metal vapour vacuum arc plasmas and ion sources” appeared in vol. 1 of Plasma Sources Science and Technology, it is a great opportunity to re-visit the issue of pressure ionization, a non-ideal plasma effect, and put it in perspective to the many other factors that influence observable charge state distributions, such as the role of the cathode material, the path in the density-temperature phase diagram, the “noise” in vacuum arc plasma as described by a fractal model approach, the effects of external magnetic fields and charge exchange collisions with neutrals. A much more complex image of the vacuum arc plasma emerges putting decades of experimentation and modeling in perspective.

  14. Application of electrostatic Langmuir probe to atmospheric arc plasmas producing nanostructures

    SciTech Connect (OSTI)

    Shashurin, A.; Li, J.; Zhuang, T.; Keidar, M.; Beilis, I. I.

    2011-07-15

    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.

  15. Volatilization and redox testing in a DC arc melter: FY-93 and FY-94

    SciTech Connect (OSTI)

    Grandy, J.D.; Sears, J.W.; Soelberg, N.R.; Reimann, G.A.; McIlwain, M.E.

    1996-07-01

    The purpose of these experiments was to study the dissolution, retention, volatilization, and trapping of transuranic radionuclide elements (TRUs), mixed fission and activation products, and high vapor pressure metals (HVPMS) during processing in a high temperature arc furnace. In all cases, surrogate elements (lanthanides) were used in place of radioactive ones. The experiments were conducted utilizing a small DC arc melter developed at the Idaho National Engineering Laboratory (INEL) Research Center (IRC). The small arc melter was originally developed in 1992 and has been used previously for waste form studies of iron enriched basalt (IEB) and IEB with zirconium and titanium additions (IEB4). Section 3 contains a description of the small arc melter and its operational capabilities are discussed in Chapter 4. The remainder of the document describes each testing program and then discusses results and findings.

  16. Filters for cathodic arc plasmas

    DOE Patents [OSTI]

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

    2002-01-01

    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.

  17. Turbulence Intensity Comparisons for Pipes with/without Welds

    E-Print Network [OSTI]

    McDonald, Kirk

    Turbulence Intensity Comparisons for Pipes with/without Welds Oct. 24, 2012 Yan Zhan 1 #12;Outline · Line Plot of TI at the Pipe Exit · Contour of Turbulence Intensity (Page 4 - 9) ­ with a weld - 3.2M ­ with a weld ­ 2.5M · Contour of Turbulence Intensity (Page 10 - 15) ­ with a weld - 3.2M ­ without a weld ­ 3

  18. Random Curves by Conformal Welding

    E-Print Network [OSTI]

    K. Astala; P. Jones; A. Kupiainen; E. Saksman

    2009-12-17

    We construct a conformally invariant random family of closed curves in the plane by welding of random homeomorphisms of the unit circle given in terms of the exponential of Gaussian Free Field. We conjecture that our curves are locally related to SLE$(\\kappa)$ for $\\kappa<4$.

  19. Random Curves by Conformal Welding

    E-Print Network [OSTI]

    Astala, K; Kupiainen, A; Saksman, E

    2009-01-01

    We construct a conformally invariant random family of closed curves in the plane by welding of random homeomorphisms of the unit circle given in terms of the exponential of Gaussian Free Field. We conjecture that our curves are locally related to SLE$(\\kappa)$ for $\\kappa<4$.

  20. Modeling of Heat and Mass Transfer in Fusion Welding (Book) ...

    Office of Scientific and Technical Information (OSTI)

    Book: Modeling of Heat and Mass Transfer in Fusion Welding Citation Details In-Document Search Title: Modeling of Heat and Mass Transfer in Fusion Welding In fusion welding, parts...

  1. Charge state dependence of cathodic vacuum arc ion energy and velocity distributions

    E-Print Network [OSTI]

    Rosen, Johanna; Schneider, Jochen M.; Anders, Andre

    2006-01-01

    velocity in vacuum arc plasmas by arc current perturbationin aluminum vacuum arc plasma. We show that the conflictingdistinguished. Cathodic vacuum arc plasma is well known to

  2. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, Steven (Livermore, CA)

    1995-01-01

    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. Method and device for frictional welding

    DOE Patents [OSTI]

    Peacock, H.B.

    1992-10-13

    A method is described 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 canister 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. 5 figs.

  4. Method and device for frictional welding

    DOE Patents [OSTI]

    Peacock, H.B.

    1991-01-01

    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.

  5. Method and device for frictional welding

    DOE Patents [OSTI]

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

    1992-01-01

    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.

  6. Passively damped vibration welding system and method

    DOE Patents [OSTI]

    Tan, Chin-An; Kang, Bongsu; Cai, Wayne W.; Wu, Tao

    2013-04-02

    A vibration welding system includes a controller, welding horn, an anvil, and a passive damping mechanism (PDM). The controller generates an input signal having a calibrated frequency. The horn vibrates in a desirable first direction at the calibrated frequency in response to the input signal to form a weld in a work piece. The PDM is positioned with respect to the system, and substantially damps or attenuates vibration in an undesirable second direction. A method includes connecting the PDM having calibrated properties and a natural frequency to an anvil of an ultrasonic welding system. Then, an input signal is generated using a weld controller. The method includes vibrating a welding horn in a desirable direction in response to the input signal, and passively damping vibration in an undesirable direction using the PDM.

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

    E-Print Network [OSTI]

    2012-05-02

    yields a modular operad structure on the homology level. .... 1.4.2 Elements as weighted arc families A weight function wt on an arc family ...... Figure 6. I, the identity and II, the arc family ? yielding the BV operator ..... weighted arc family obtained by scaling all weights of arcs incident to ?i of ? homoge- ..... A careful analysis.

  8. Gamma-Normal Probability Distribution Arc Length

    E-Print Network [OSTI]

    Hesam

    2014-11-04

    ... Engineering, Mazandaran University of Science and Technology, Babol, Iran ... the arcs are assumed to represent transportation time or cost rather than the ...

  9. Effect of welding sequence on welding-induced-alignment-distortion in packaging of butterfly laser diode modules: Simulation and experiment

    E-Print Network [OSTI]

    Lin, Y M; Eichele, C; Shi, F G

    2005-01-01

    and M. Rodighiero, “Laser welding produces high-yield as-Y. M. Lin, and F. G. Shi, “Welding induced alignment dis-packages: effect of laser welding sequence,” in Proc. SPIE,

  10. Modelling of friction stir spot welding

    E-Print Network [OSTI]

    Reilly, Aidan

    2013-07-09

    1.2 Friction stir process descriptions . . . . . . . . . . . . . . . . . 5 1.2.1 Friction stir welding . . . . . . . . . . . . . . . . . . . 5 1.2.2 Friction stir spot welding (FSSW) . . . . . . . . . . . . 7 1.2.3 Pinless FSSW... processes . . . . . . . 25 2.3.5 Empirical testing and validation . . . . . . . . . . . . . 39 vii 2.3.6 Microstructural modelling . . . . . . . . . . . . . . . . 41 2.3.7 Modelling of related non-welding processes . . . . . . . 42 2.4 Constitutive data...

  11. An interchangeable-cathode vacuum arc plasma source

    SciTech Connect (OSTI)

    Olson, David K.; Peterson, Bryan G.; Hart, Grant W.

    2010-01-15

    A simplified vacuum arc design [based on metal vapor vacuum arc (MeVVA) concepts] is employed as a plasma source for a study of a {sup 7}Be non-neutral plasma. The design includes a mechanism for interchanging the cathode source. Testing of the plasma source showed that it is capable of producing on the order of 10{sup 12} charges at confinable energies using a boron-carbide disk as the cathode target. The design is simplified from typical designs for lower energy and lower density applications by using only the trigger spark rather than the full vacuum arc in high current ion beam designs. The interchangeability of the cathode design gives the source the ability to replace only the source sample, simplifying use of radioactive materials in the plasma source. The sample can also be replaced with a completely different conductive material. The design can be easily modified for use in other plasma confinement or full MeVVA applications.

  12. Dynamic Characterization of Spot Welds | Department of Energy

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

    Welds Dynamic Characterization of Spot Welds Presentation from the U.S. DOE Office of Vehicle Technologies "Mega" Merit Review 2008 on February 25, 2008 in Bethesda, Maryland....

  13. Material flow during friction stir welding: A thermo-mechanically...

    Office of Scientific and Technical Information (OSTI)

    Material flow during friction stir welding: A thermo-mechanically fully coupled CFD study Citation Details In-Document Search Title: Material flow during friction stir welding: A...

  14. A Submarine Welded Ignimbrite-Crystal-Rich Sandstone Facies Associatio...

    Open Energy Info (EERE)

    ignimbrite). Breccia units composed of welded ignimbrite clasts and crystal-rich matrix (e.g., Comstock and Anthony Road ignimbrite breccias) imply that some welded...

  15. Welding of Dissimilar Materials Combinations for Automotive Applicatio...

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

    0, 2011 Welding of Dissimilar Materials Combinations for Automotive Applications Jerry E. Gould Technology Leader Resistance and Solid State Welding ph: 614-688-5121 e-mail:...

  16. Groundwater Modeling in ArcView: by integrating ArcView, MODFLOW and

    E-Print Network [OSTI]

    Sengupta, Raja

    Groundwater Modeling in ArcView: by integrating ArcView, MODFLOW and MODPATH Abstract Modeling. This paper addresses groundwater modeling which is one of the many entities in environmental modeling in ArcView 3.2a. The objective was to create an integrated system where a user could do groundwater

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

    SciTech Connect (OSTI)

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

    2007-06-21

    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.

  18. Improving Fatigue Performance of AHSS Welds

    SciTech Connect (OSTI)

    Feng, Zhili; Yu, Xinghua; Erdman, III, Donald L.; Wang, Yanli; Kelly, Steve; Hou, Wenkao; Yan, Benda; Wang, Zhifeng; Yu, Zhenzhen; Liu, Stephen

    2015-03-01

    Reported herein is technical progress on a U.S. Department of Energy CRADA project with industry cost-share aimed at developing the technical basis and demonstrate the viability of innovative in-situ weld residual stresses mitigation technology that can substantially improve the weld fatigue performance and durability of auto-body structures. The developed technology would be costeffective and practical in high-volume vehicle production environment. Enhancing weld fatigue performance would address a critical technology gap that impedes the widespread use of advanced high-strength steels (AHSS) and other lightweight materials for auto body structure light-weighting. This means that the automotive industry can take full advantage of the AHSS in strength, durability and crashworthiness without the concern of the relatively weak weld fatigue performance. The project comprises both technological innovations in weld residual stress mitigation and due-diligence residual stress measurement and fatigue performance evaluation. Two approaches were investigated. The first one was the use of low temperature phase transformation (LTPT) weld filler wire, and the second focused on novel thermo-mechanical stress management technique. Both technical approaches have resulted in considerable improvement in fatigue lives of welded joints made of high-strength steels. Synchrotron diffraction measurement confirmed the reduction of high tensile weld residual stresses by the two weld residual stress mitigation techniques.

  19. Welding the AT-400A Containment Vessel

    SciTech Connect (OSTI)

    Brandon, E.

    1998-11-01

    Early in 1994, the Department of Energy assigned Sandia National Laboratories the responsibility for designing and providing the welding system for the girth weld for the AT-400A containment vessel. (The AT-400A container is employed for the shipment and long-term storage of the nuclear weapon pits being returned from the nation's nuclear arsenal.) Mason Hanger Corporation's Pantex Plant was chosen to be the production facility. The project was successfully completed by providing and implementing a turnkey welding system and qualified welding procedure at the Pantex Plant. The welding system was transferred to Pantex and a pilot lot of 20 AT-400A containers with W48 pits was welded in August 1997. This document is intended to bring together the AT-400A welding system and product (girth weld) requirements and the activities conducted to meet those requirements. This document alone is not a complete compilation of the welding development activities but is meant to be a summary to be used with the applicable references.

  20. Welding shield for coupling heaters

    DOE Patents [OSTI]

    Menotti, James Louis (Dickinson, TX)

    2010-03-09

    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.

  1. Polymer Welding: Strength Through Entanglements

    E-Print Network [OSTI]

    Ting Ge; Flint Pierce; Dvora Perahia; Gary S. Grest; Mark O. Robbins

    2012-11-29

    Large-scale simulations of thermal welding of polymers are performed to investigate the rise of mechanical strength at the polymer-polymer interface with the welding time. The welding process is in the core of integrating polymeric elements into devices as well as in thermal induced healing of polymers; processes that require development of interfacial strength equal to that of the bulk. Our simulations show that the interfacial strength saturates at the bulk shear strength much before polymers diffuse by their radius of gyration. Along with the strength increase, the dominant failure mode changes from chain pullout at the interface to chain scission as in the bulk. Formation of sufficient entanglements across the interface, which we track using a Primitive Path Analysis is required to arrest catastrophic chain pullout at the interface. The bulk response is not fully recovered until the density of entanglements at the interface reaches the bulk value. Moreover, the increase of interfacial strength before saturation is proportional to the number of interfacial entanglements between chains from opposite sides.

  2. Progress Report for Diffusion Welding of the NGNP Process Application Heat Exchangers

    SciTech Connect (OSTI)

    R.E. Mizia; D.E. Clark; M.V. Glazoff; T.E. Lister; T.L. Trowbridge

    2011-12-01

    The U.S. Department of Energy selected the high temperature gas-cooled reactor as the basis for the Next Generation Nuclear Plant (NGNP). The NGNP will demonstrate the use of nuclear power for electricity, hydrogen production, and process heat applications. The NGNP Project is currently investigating the use of metallic, diffusion welded, compact heat exchangers to transfer heat from the primary (reactor side) heat transport system to the secondary heat transport system. An intermediate heat exchanger will transfer this heat to downstream applications such as hydrogen production, process heat, and electricity generation. The channeled plates that make up the heat transfer surfaces of the intermediate heat exchanger will have to be assembled into an array by diffusion welding. This report describes the preliminary results of a scoping study that evaluated the diffusion welding process parameters and the resultant mechanical properties of diffusion welded joints using Alloy 800H. The long-term goal of the program is to progress towards demonstration of small heat exchanger unit cells fabricated with diffusion welds. Demonstration through mechanical testing of the unit cells will support American Society of Mechanical Engineers rules and standards development, reduce technical risk, and provide proof of concept for heat exchanger fabrication methods needed to deploy heat exchangers in several potential NGNP configurations.1 Researchers also evaluated the usefulness of modern thermodynamic and diffusion computational tools (Thermo-Calc and Dictra) in optimizing the parameters for diffusion welding of Alloy 800H. The modeling efforts suggested a temperature of 1150 C for 1 hour with an applied pressure of 5 MPa using 15 {micro}m nickel foil as joint filler to reduce chromium oxidation on the welded surfaces. Good agreement between modeled and experimentally determined concentration gradients was achieved

  3. Asymmetric injection of cathodic arc plasma into a macroparticle filter

    E-Print Network [OSTI]

    Anders, Andre; MacGill, Robert A.

    2004-01-01

    setup. The cathodic arc plasma source is flange-mounted andfirewall" twist filter arc plasma source F IG. 1 Current (A)Injection of Cathodic Arc Plasma into a Macroparticle Filter

  4. Filtered cathodic arc deposition with ion-species-selective bias

    E-Print Network [OSTI]

    Anders, Andre; Pasaja, Nitisak; Sansongsiri, Sakon; Lim, Sunnie H.N.

    2006-01-01

    Photograph of a cathodic arc plasma source with two cathodesof ions of cathodic arc plasmas. The selection was made forAbstract A dual-cathode arc plasma source was combined with

  5. Measurement of total ion current from vacuum arc plasma sources

    E-Print Network [OSTI]

    Oks, Efim M.; Savkin, Konstantin P.; Yushkov, Georgiu Yu.; Nikolaev, Alexey G.; Anders, A.; Brown, Ian G.

    2005-01-01

    A. Anders, Cathodic Arc Plasma Deposition: From Fractalion current from vacuum arc plasma sources E. M. Oks, K. P.ion current from vacuum arc plasma sources E. M. Oks, K. P.

  6. Vacuum Arc Ion Sources: Recent Developments and Applications

    E-Print Network [OSTI]

    Brown, Ian; Oks, Efim

    2005-01-01

    charge states in vacuum arc plasmas using a 'current spike'of pulsed vacuum arc plasmas in strong magnetic fields",of electrons in vacuum arc plasmas", Rev. Sci. Instrum. ,

  7. Measurement of total ion flux in vacuum Arc discharges

    E-Print Network [OSTI]

    Anders, Andre; Oks, Efim M.; Yushkov, Georgy Yu.; Brown, Ian G.

    2004-01-01

    in high current vacuum arc plasma in a magnetic field," IEEEdistributions of vacuum arc plasmas: The origin of species,"high-current vacuum arc plasmas," IEEE Trans. Plasma Sci. ,

  8. Multi-mode ultrasonic welding control and optimization

    DOE Patents [OSTI]

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

    2013-05-28

    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.

  9. Purification of tantalum by plasma arc melting

    DOE Patents [OSTI]

    Dunn, Paul S. (Santa Fe, NM); Korzekwa, Deniece R. (Los Alamos, NM)

    1999-01-01

    Purification of tantalum by plasma arc melting. The level of oxygen and carbon impurities in tantalum was reduced by plasma arc melting the tantalum using a flowing plasma gas generated from a gas mixture of helium and hydrogen. The flowing plasma gases of the present invention were found to be superior to other known flowing plasma gases used for this purpose.

  10. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, Ronald S. (Livermore, CA)

    1987-01-01

    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.

  11. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1985-08-05

    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.

  12. Low voltage arc formation in railguns

    DOE Patents [OSTI]

    Hawke, R.S.

    1987-11-17

    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.

  13. 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...

  14. Boron nitride ablation studies in arc jet facilities (Conference...

    Office of Scientific and Technical Information (OSTI)

    Boron nitride ablation studies in arc jet facilities Citation Details In-Document Search Title: Boron nitride ablation studies in arc jet facilities You are accessing a document...

  15. Design of Welding Alloys Creep and Toughness

    E-Print Network [OSTI]

    Marimuthu, Murugananth

    The subject of welding is challenging because of its complexity and because its applications are in the majority of cases, safety critical. The work presented in this thesis deals with both these aspects from the point of view of welding alloys...

  16. Manual tube-to-tubesheet welding torch

    DOE Patents [OSTI]

    Kiefer, Joseph H. (Tampa, FL); Smith, Danny J. (Tampa, FL)

    1982-01-01

    A welding torch made of a high temperature plastic which fits over a tube intermediate the ends thereof for welding the juncture between the tube and the back side of a tube plate and has a ballooned end in which an electrode, filler wire guide, fiber optic bundle, and blanketing gas duct are disposed.

  17. Effect of Scratches on Pinch Welds

    SciTech Connect (OSTI)

    Korinko, P

    2005-10-11

    Fill stems for tritium reservoirs have stringent scratch requirements such that any indications that appear to have depth are cause for rework or rejection. A scoping study was undertaken to evaluate the effect of scratches approximately 0.0015 to 0.002 inch deep on the fitness for service and bond quality. The stems were characterized using borescope before and after welding. The four stems were welded with near optimal weld parameters, proof tested, and examined metallographically. The stems were radiographed, proof tested, and examined metallographically. The scratches did not adversely affect (1) the weld integrity based on radiography, (2) the ability to withstand the proof pressure, and (3) the weld quality based on metallographic cross-sections. Based on these limited results at a nominal weld current, the weld process is very robust. It may be able to recover from manufacturing defects and inspection anomalies worse than those expected for typical fill stem manufacturing processes; additional testing specific to each application over a range of weld heats is needed to verify applicability of these results.

  18. Characterization of Multilayered Multipass Friction Stir Weld on ASTM A572 G50 Steel

    SciTech Connect (OSTI)

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

    2014-01-01

    A multilayered multipass friction stir weld (MM-FSW) on ASTM A572 Grade 50 steel was characterized to understand its potential application for thick-section structures. The 15-mm-thick section was fabricated by stacking up three steel plates and then friction stir welding the plates together in a total of 5 passes. The unique butt/lap joint configuration encountered in the multilayer weld was examined to understand the effect of tool rotation direction on the joint quality especially the formation of hooking defect. Charpy V-notch impact toughness tests showed generally higher impact toughness energy for the stir zone than the base metal with a ductile fracture mode. The microhardness value was measured from 195 to 220 HV in the stir zone, while the base metal showed an average value of 170 HV. The microstructure in the stir zone and the adjacent heat affected zone was quantified using Optical and Scanning Electron Microscopy (SEM) including Electron Backscatter Diffraction (EBSD). The increased toughness and hardness were correlated with the refined microstructure in stir zone, resulting from severe plastic deformation and subsequent dynamic recrystallization during friction stir welding.

  19. MODELLING OF MICROSTRUCTURE IN NOVEL HIGH STRENGTH STEEL WELDS

    E-Print Network [OSTI]

    Cambridge, University of

    MODELLING OF MICROSTRUCTURE IN NOVEL HIGH STRENGTH STEEL WELDS by Gethin Rees Ernmanuel College . . . . Nomenclature List CHAPTER 1 Introduction 1.1 An Introduction to the Welding Process 1.1.1 The Welding Processes . . 1.1.2 The Welding Thermal Cycle 1.2 An Introduction to the Metallurgy of Steel 1.2.1 Pure Iron

  20. AUTOMATING WELDED GUSSET PLATE CONNECTIONS IN PLANAR TRUSS STRUCTURES

    E-Print Network [OSTI]

    Papalambros, Panos

    AUTOMATING WELDED GUSSET PLATE CONNECTIONS IN PLANAR TRUSS STRUCTURES Benjamin Linder Department generates the weld geometry and the gusset plate geometry for each joint of a truss. The program of welded truss connections using gusset plates. The following steps are necessary for the design of welded

  1. Weld: A Multithreading Technique Towards Latency-tolerant VLIW Processors

    E-Print Network [OSTI]

    Conte, Thomas M.

    Weld: A Multithreading Technique Towards Latency- tolerant VLIW Processors Emre Ã?zer, Thomas M architecture model, named Weld, for VLIW processors. Weld integrates multithreading support into a VLIW a novel hardware technique called operation welding that merges operations from different threads

  2. Optical Inspection of Welding Seams Fabian Timm1,2

    E-Print Network [OSTI]

    Optical Inspection of Welding Seams Fabian Timm1,2 , Thomas Martinetz1 , and Erhardt Barth1,2 1 present a framework for automatic inspection of welding seams based on specular reflections. To this end by using welding techniques. Soldering and welding techniques are common in diverse areas such as printed

  3. Subaqueous Explosive Eruption and Welding of Pyroclastic Deposits

    E-Print Network [OSTI]

    Busby, Cathy

    Subaqueous Explosive Eruption and Welding of Pyroclastic Deposits Peter Kokelaar and Cathy Busby fabrics indicative of welding of glass shards and pumice at temperatures >500"C. The occurrence emplacement temperature in pyroclas- tic deposits is welding. Welding is hot-state viscous deformation

  4. Virtual Welded - Joint Design Integrating Advanced Materials and Processing Technology

    SciTech Connect (OSTI)

    Yang, Zhishang; Ludewig, Howard W.; Babu, S. Suresh

    2005-06-30

    Virtual Welede-Joint Design, a systematic modeling approach, has been developed in this project to predict the relationship of welding process, microstructure, properties, residual stress, and the ultimate weld fatique strength. This systematic modeling approach was applied in the welding of high strength steel. A special welding wire was developed in this project to introduce compressive residual stress at weld toe. The results from both modeling and experiments demonstrated that more than 10x fatique life improvement can be acheived in high strength steel welds by the combination of compressive residual stress from the special welding wire and the desired weld bead shape from a unique welding process. The results indicate a technology breakthrough in the design of lightweight and high fatique performance welded structures using high strength steels.

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

    E-Print Network [OSTI]

    Chong, J. W. S.

    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 ...

  6. Deformation Behavior of Laser Welds in High Temperature Oxidation Resistant Fe-Cr-Al Alloys for Fuel Cladding Applications

    SciTech Connect (OSTI)

    Field, Kevin G; Gussev, Maxim N; Yamamoto, Yukinori; Snead, Lance Lewis

    2014-11-01

    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 of three model alloys in a range of Fe-(13-17.5)Cr-(3-4.4)Al in weight percent with a minor addition of yttrium using laser-welding techniques. A detailed study on the mechanical performance of bead-on-plate welds has been carried out to determine the performance of welds as a function of alloy composition. Laser welding resulted in a defect free weld devoid of cracking or inclusions for all alloys studied. 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. No significant correlation was found between the deformation behavior/mechanical performance of welds and the level of Cr or Al in the alloy ranges studied.

  7. Diffusion Welding of Alloys for Molten Salt Service - Status Report

    SciTech Connect (OSTI)

    Denis Clark; Ronald Mizia

    2012-05-01

    The present work is concerned with heat exchanger development for molten salt service, including the proposed molten salt reactor (MSR), a homogeneous reactor in which the fuel is dissolved in a circulating fluid of molten salt. It is an outgrowth of recent work done under the Next Generation Nuclear Plant (NGNP) program; what the two reactor systems have in common is an inherently safe nuclear plant with a high outlet temperature that is useful for process heat as well as more conventional generation The NGNP program was tasked with investigating the application of a new generation of nuclear power plants to a variety of energy needs. One baseline reactor design for this program is a high temperature, gas-cooled reactor (HTGR), which provides many options for energy use. These might include the conventional Rankine cycle (steam turbine) generation of electricity, but also other methods: for example, Brayton cycle (gas turbine) electrical generation, and the direct use of the high temperatures characteristic of HTGR output for process heat in the chemical industry. Such process heat is currently generated by burning fossil fuels, and is a major contributor to the carbon footprint of the chemical and petrochemical industries. The HTGR, based on graphite fuel elements, can produce very high output temperatures; ideally, temperatures of 900 C or even greater, which has significant energy advantages. Such temperatures are, of course, at the frontiers of materials limitations, at the upper end of the performance envelope of the metallic materials for which robust construction codes exist, and within the realm of ceramic materials, the fabrication and joining of which, on the scale of large energy systems, are at an earlier stage of development. A considerable amount of work was done in the diffusion welding of materials of interest for HTGR service with alloys such as 617 and 800H. The MSR output temperature is also materials limited, and is projected at about 700 C. (RR E) A different set of alloys, such as Alloy N and 242, are needed to handle molten salts at this temperature. The diffusion welding development work described here builds on techniques developed during the NGNP work, as applied to these alloys. There is also the matter of dissimilar metal welding, since alloys suitable for salt service are generally not suited for service in gaseous oxidizing environments, and vice versa, and welding is required for the Class I boundaries in these systems, as identified in the relevant ASME codes.

  8. Diffusion Welding of Alloys for Molten Salt Service - Status Report

    SciTech Connect (OSTI)

    Denis Clark; Ronald Mizia; Piyush Sabharwall

    2012-09-01

    The present work is concerned with heat exchanger development for molten salt service, including the proposed molten salt reactor (MSR), a homogeneous reactor in which the fuel is dissolved in a circulating fluid of molten salt. It is an outgrowth of recent work done under the Next Generation Nuclear Plant (NGNP) program; what the two reactor systems have in common is an inherently safe nuclear plant with a high outlet temperature that is useful for process heat as well as more conventional generation The NGNP program was tasked with investigating the application of a new generation of nuclear power plants to a variety of energy needs. One baseline reactor design for this program is a high temperature, gas-cooled reactor (HTGR), which provides many options for energy use. These might include the conventional Rankine cycle (steam turbine) generation of electricity, but also other methods: for example, Brayton cycle (gas turbine) electrical generation, and the direct use of the high temperatures characteristic of HTGR output for process heat in the chemical industry. Such process heat is currently generated by burning fossil fuels, and is a major contributor to the carbon footprint of the chemical and petrochemical industries. The HTGR, based on graphite fuel elements, can produce very high output temperatures; ideally, temperatures of 900 °C or even greater, which has significant energy advantages. Such temperatures are, of course, at the frontiers of materials limitations, at the upper end of the performance envelope of the metallic materials for which robust construction codes exist, and within the realm of ceramic materials, the fabrication and joining of which, on the scale of large energy systems, are at an earlier stage of development. A considerable amount of work was done in the diffusion welding of materials of interest for HTGR service with alloys such as 617 and 800H. The MSR output temperature is also materials limited, and is projected at about 700 °C. (RR E) A different set of alloys, such as Alloy N and 242, are needed to handle molten salts at this temperature. The diffusion welding development work described here builds on techniques developed during the NGNP work, as applied to these alloys. There is also the matter of dissimilar metal welding, since alloys suitable for salt service are generally not suited for service in gaseous oxidizing environments, and vice versa, and welding is required for the Class I boundaries in these systems, as identified in the relevant ASME codes.

  9. Magnetic-cusp, cathodic-arc source

    DOE Patents [OSTI]

    Falabella, S.

    1995-11-21

    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.

  10. Plasma torch with liquid metal electrodes

    SciTech Connect (OSTI)

    Predtechenskii, M.R.; Tukhto, O.M.

    2006-03-15

    In order to eliminate the negative effect of erosion processes on electrodes in arc plasma generators, a new scheme of arc discharge was proposed in which the surface of a molten metal acts as electrodes. A plasma reactor was designed on the basis of this concept. The electrophysical characteristics of such a discharge in steam and air as plasma gases were studied. Experiments on destruction of toxic polychlorinated biphenyls and steam coal gasification were performed.

  11. ZrN coatings deposited by high power impulse magnetron sputtering and cathodic arc techniques

    SciTech Connect (OSTI)

    Purandare, Yashodhan Ehiasarian, Arutiun; Hovsepian, Papken; Santana, Antonio

    2014-05-15

    Zirconium nitride (ZrN) coatings were deposited on 1??m finish high speed steel and 316L stainless steel test coupons. Cathodic Arc (CA) and High Power Impulse Magnetron Sputtering (HIPIMS) + Unbalanced Magnetron Sputtering (UBM) techniques were utilized to deposit coatings. CA plasmas are known to be rich in metal and gas ions of the depositing species as well as macroparticles (droplets) emitted from the arc sports. Combining HIPIMS technique with UBM in the same deposition process facilitated increased ion bombardment on the depositing species during coating growth maintaining high deposition rate. Prior to coating deposition, substrates were pretreated with Zr{sup +} rich plasma, for both arc deposited and HIPIMS deposited coatings, which led to a very high scratch adhesion value (L{sub C2}) of 100 N. Characterization results revealed the overall thickness of the coatings in the range of 2.5??m with hardness in the range of 30–40?GPa depending on the deposition technique. Cross-sectional transmission electron microscopy and tribological experiments such as dry sliding wear tests and corrosion studies have been utilized to study the effects of ion bombardment on the structure and properties of these coatings. In all the cases, HIPIMS assisted UBM deposited coating fared equal or better than the arc deposited coatings, the reasons being discussed in this paper. Thus H+U coatings provide a good alternative to arc deposited where smooth, dense coatings are required and macrodroplets cannot be tolerated.

  12. Apparatus for coating a surface with a metal utilizing a plasma source

    DOE Patents [OSTI]

    Brown, Ian G. (Berkeley, CA); MacGill, Robert A. (Richmond, CA); Galvin, James E. (Emeryville, CA)

    1991-01-01

    An apparatus and method for coating or layering a surface with a metal utilizing a metal vapor vacuum arc plasma source. The apparatus includes a trigger mechanism for actuating the metal vacuum vapor arc plasma source in a pulsed mode at a predetermined rate. The surface or substrate to be coated or layered is supported in position with the plasma source in a vacuum chamber. The surface is electrically biased for a selected period of time during the pulsed mode of operation of the plasma source. Both the pulsing of the metal vapor vacuum arc plasma source and the electrical biasing of the surface are synchronized for selected periods of time.

  13. Motion characteristics of long ac arcs in atmospheric air

    SciTech Connect (OSTI)

    Gu Shanqiang; He Jinliang; Zeng Rong; Zhang Bo; Xu Guozheng; Chen Weijiang

    2007-01-29

    Experiments on the motion of long alternating current arcs in atmospheric air show that the anode and cathode arc roots have different motion characteristics because of different formation mechanisms. During a half cycle of the arc current, the anode arc root moves towards the direction of magnetic force and occasionally has a jumping motion, while the cathode arc root moves sufficiently slow to consider it stationary and hardly has any jump. The arc column has a complex shape and moves under the drive of the magnetic force and is also quickened by the lower arc root.

  14. Detection of arcs in automotive electrical systems

    E-Print Network [OSTI]

    Mishrikey, Matthew David

    2005-01-01

    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, ...

  15. Hawley ArcGIS Desktop III: GIS Workflows and Analysis Page 1 ArcGIS Desktop III

    E-Print Network [OSTI]

    Bier, Martin

    Hawley ArcGIS Desktop III: GIS Workflows and Analysis Page 1 ArcGIS Desktop III: GIS Workflows and Analysis Overview This 2-day course builds on the skills and knowledge taught in ArcGIS Desktop II: Tools a challenging analysis project. Audience This course is for experienced ArcGIS users who want to learn more

  16. ArcGIS Explorer Online Extended Use Quick Guide ArcGIS Explorer Online--GIS for Everyone

    E-Print Network [OSTI]

    Wright, Dawn Jeannine

    ArcGIS Explorer Online Extended Use Quick Guide ArcGIS Explorer Online--GIS for Everyone Creating notes, photo links, and presentations ArcGIS Explorer Online (AGXO) is a browser-based GIS viewer, perform queries and create presentations. This quick guide is an extension of the Introduction to ArcGIS

  17. Klystron Gun Arcing and Modulator Protection

    SciTech Connect (OSTI)

    Gold, S

    2004-05-04

    The demand for 500 kV and 265 amperes peak to power an X-Band klystron brings up protection issues for klystron faults and the energy dumped into the arc from the modulator. This situation is made worse when more than one klystron will be driven from a single modulator, such as the existing schemes for running two and eight klystrons. High power pulsed klystrons have traditionally be powered by line type modulators which match the driving impedance with the load impedance and therefore current limit at twice the operating current. Multiple klystrons have the added problems of a lower modulator source impedance and added stray capacitance, which converts into appreciable energy at high voltages like 500kV. SLAC has measured the energy dumped into klystron arcs in a single and dual klystron configuration at the 400 to 450 kV level and found interesting characteristics in the arc formation. The author will present measured data from klystron arcs powered from line-type modulators in several configurations. The questions arise as to how the newly designed solid-state modulators, running multiple tubes, will react to a klystron arc and how much energy will be dumped into the arc.

  18. Ion source with improved primary arc collimation

    DOE Patents [OSTI]

    Dagenhart, William K. (Oak Ridge, TN)

    1985-01-01

    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.

  19. Prediction of Welding Distortion Panagiotis Michaleris and Andrew DeBiccari

    E-Print Network [OSTI]

    Michaleris, Panagiotis

    1 Prediction of Welding Distortion Panagiotis Michaleris and Andrew DeBiccari Edison Welding Institute Columbus, Ohio ABSTRACT. This paper presents a numerical analysis technique for predicting welding induced distortion. The technique combines two dimensional welding simulations with three dimensional

  20. Pulsed Magnetic Welding for Advanced Core and Cladding Steel

    SciTech Connect (OSTI)

    Cao, Guoping; Yang, Yong

    2013-12-19

    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.

  1. Method and apparatus for real time weld monitoring

    DOE Patents [OSTI]

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

    1997-01-01

    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.

  2. Vibration welding system with thin film sensor

    DOE Patents [OSTI]

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

    2014-03-18

    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.

  3. Effect of the overlapping factor on the microstructure and mechanical properties of pulsed Nd:YAG laser welded Ti6Al4V sheets

    SciTech Connect (OSTI)

    Gao, Xiao-Long; Liu, Jing; Zhang, Lin-Jie, E-mail: zhanglinjie@mail.xjtu.edu.cn; Zhang, Jian-Xun

    2014-07-01

    The effect of the overlapping factor on the microstructures and mechanical properties of pulsed Nd:YAG laser welded Ti6Al4V alloy sheets was investigated by microstructural observations, microhardness tests, tensile tests and fatigue tests. A microstructural examination shows that by increasing the overlapping factor, the grains in the fusion zone become coarser, and the width of the heat affected zone increases. As overlapping factor increases, the width of region composed completely of martensite ?? and the secondary ? phase in the heat affected zone increases, consequently the gradient of microstructure along the direction from the fusion zone to base metal decreases, so does the gradient of microhardness. The results of tensile and fatigue tests reveal that the joints made using medium overlapping factor exhibit better mechanical properties than those welded with low and high overlapping factors. Based on the experimental results, it can be stated that a sound weld of Ti6Al4V alloy can be obtained if an appropriate overlapping factor is used. - Highlights: • The weld quality of Ti6Al4V alloy under various overlapping factors was assessed. • Tensile and fatigue tests were conducted with as-welded specimen. • Localized strain across the weld was measured using DIC photogrammetry system. • A sound weld of Ti6Al4V alloy is obtained by using right overlapping factor.

  4. Measurements of the Ion Species of Cathodic Arc Plasma in an Axial Magnetic Field

    SciTech Connect (OSTI)

    Oks, Efim; Anders, Andre

    2010-10-19

    Metal and gas ion species and their charge state distributions were measured for pulsed copper cathodic arcs in argon background gas in the presence of an axial magnetic field. It was found that changing the cathode position relative to anode and ion extraction system as well as increasing the gas pressure did not much affect the arc burning voltage and the related power dissipation. However, the burning voltage and power dissipation greatly increased as the magnetic field strength was increased. The fraction of metal ions and the mean ion charge state were reduced as the discharge length was increased. The observations can be explained by the combination of charge exchange collisions and electron impact ionization. They confirm that previously published data on characteristic material-dependent charge state distributions (e.g., Anders and Yushkov, J. Appl. Phys., Vol. 91, pp. 4824-4832, 2002) are not universal but valid for high vacuum conditions and the specifics of the applied magnetic fields.

  5. Friction Stir Spot Welding of Advanced High Strength Steels

    SciTech Connect (OSTI)

    Hovanski, Yuri; Grant, Glenn J.; Santella, M. L.

    2009-11-13

    Friction stir spot welding techniques were developed to successfully join several advanced high strength steels. Two distinct tool materials were evaluated to determine the effect of tool materials on the process parameters and joint properties. Welds were characterized primarily via lap shear, microhardness, and optical microscopy. Friction stir spot welds were compared to the resistance spot welds in similar strength alloys by using the AWS standard for resistance spot welding high strength steels. As further comparison, a primitive cost comparison between the two joining processes was developed, which included an evaluation of the future cost prospects of friction stir spot welding in advanced high strength steels.

  6. Aluminum Tailor-Welded Blanks for High Volume Automotive Applications

    SciTech Connect (OSTI)

    Hovanski, Yuri; Upadhyay, Piyush; Pilli, Siva Prasad; Carlson, Blair; Carsley, John; Hartfield-Wunsch, Susan; Eisenmenger, Mark

    2014-02-04

    A Design of Experiment based approach is used to systematically investigate relationships between 8 different welding factors (4 related to tool geometry, 4 related to weld process control) and resulting weld properties including strength, elongation and formability in 1.2mm-2mm thick friction stir welding of AA5182-O for TWB application. The factors that result in most significant effects are elucidated. The interactions between several key factors like plunge depth, tool tilt, pin feature and pin length on the overall weld quality is discussed. Appropriate levels of factors that lead to excellent weld properties are also identified.

  7. COMPARISON OF AIR AND DEUTERIUM ON PINCH WELD BOND APPEARANCE

    SciTech Connect (OSTI)

    Korinko, P

    2005-10-11

    The effect that air and deuterium internal atmospheres have on the pinch weld bond quality was evaluated by conducting a scoping study using type 304L stainless steel LF-7 test stems that were fabricated for an associated study. Welds were made under cool, yet nominal conditions to exacerbate the influence of the atmosphere. The bond quality of the welds was directly related to the internal atmosphere with the air atmosphere welds being of lower quality than the deuterium atmosphere welds for nominally identical welding conditions.

  8. Charge state and time resolved plasma composition of a pulsed zirconium arc in a nitrogen environment

    E-Print Network [OSTI]

    Rosen, Johanna; Anders, Andre; Hultman, Lars; Schneider, Jochen M.

    2004-01-01

    of a pulsed cathodic arc plasma was investigated atof a growing film in arc plasma deposition. In the presencea titanium cathodic arc plasma at varying nitrogen pressure,

  9. Ultrathin diamond-like carbon films deposited by filtered carbon vacuum arcs

    E-Print Network [OSTI]

    Anders, Andre; Fong, Walton; Kulkarni, Ashok; Ryan, Francis W.; Bhatia, C. Singh

    2001-01-01

    Ion velocities in vacuum arc plasmas,” J. Appl. Phys. , vol.Brown, “Transport of vacuum arc plasma through straight anda filtered cathodic arc,” Plasma Sources Sci. Technol. , pp.

  10. Material and time dependence of the voltage noise generated by cathodic vacuum arcs

    E-Print Network [OSTI]

    Rosen, Johanna; Anders, Andre

    2005-01-01

    associated with plasma production and arc impedance, it wasbecause it is known that arc plasma parameters have almost “Applications of Vacuum-Arc-Produced Plasma, Ion and Electron

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

    DOE Patents [OSTI]

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

    1980-01-03

    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.

  12. Apparatus for maintaining alignment of a shrinking weld joint in an electron-beam welding operation

    DOE Patents [OSTI]

    Trent, Jett B. (Knoxville, TN); Murphy, Jimmy L. (Oak Ridge, TN)

    1981-01-01

    The present invention is directed to an apparatus for automatically maintaining a shrinking weld joint in alignment with an electron beam during an electron-beam multipass-welding operation. The apparatus utilizes a biasing device 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 is 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.

  13. Ion source with improved primary arc collimation

    DOE Patents [OSTI]

    Dagenhart, W.K.

    1983-12-16

    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.

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

    SciTech Connect (OSTI)

    Sato, Y.; Motomiya, K.; Jeyadevan, B.; Tohji, K.; Sato, G.; Ishida, H.; Hirata, T.; Hatakeyama, R.

    2005-11-01

    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.

  15. Prediction of Weld-Metal Composition During Flux-Shielded Welding

    E-Print Network [OSTI]

    Eagar, Thomas W.

    . ·due tn tire slrarr n·actian times and farge tlrcrma{ gra,fients inherent in the process. Nonetheless. In the .tint. a series (~r a1·cr one !rune/red H·dd.1. ll'itlr initialmwrgcrnt·sc l'(lrying from 0.01 pet to 3.1 pet. siliconmryi11g.from 0.002 rwt to3.2 pet. a11el lmsicin· index nrrrillg.fi·nm 0.2 to -1.0. 11·cre

  16. Supplementary Materials Christopher H. Lin Mausam Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Supplementary Materials Christopher H. Lin Mausam Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195 {chrislin,mausam,weld}@cs.washington.edu Theorem

  17. MODULAR MAGIC SUDOKU JOHN LORCH AND ELLEN WELD

    E-Print Network [OSTI]

    Lorch, John D.

    MODULAR MAGIC SUDOKU JOHN LORCH AND ELLEN WELD Abstract. A modular magic sudoku solution. 05B15. 1 #12;2 JOHN LORCH AND ELLEN WELD sudoku solution in (1) and the solution x2 given in Section

  18. Checking Your Car's 4000 Welds is Serious Business. Scientists...

    Energy Savers [EERE]

    Business. Scientists Just Made it Easier. March 4, 2015 - 10:45am Addthis Robotic welding is vital to auto manufacturing, but double checking the welds is done by hand....

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

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

    Friction Stir Spot Welding of Advanced High Strength Steels II Friction Stir Spot Welding of Advanced High Strength Steels II 2011 DOE Hydrogen and Fuel Cells Program, and Vehicle...

  20. Influence of a transverse magnetic field on arc root movements in a dc plasma torch: Diamagnetic effect of arc column

    SciTech Connect (OSTI)

    Kim, Keun Su

    2009-03-23

    The effect of a transverse magnetic field on the anodic arc root movement inside a dc plasma torch has been investigated. The arc voltage fluctuation, which represents the degree of the arc instability, was reduced to 28.6% of the original value and the high frequency components in the voltage signal also decreased in their magnitudes. The inherent arc instability in a dc thermal plasma torch seems to be suppressed by a diamagnetic effect of the arc column. Furthermore, the measured voltage wave forms indicated that the arc root attachment mode would be controllable by a transverse magnetic field.

  1. Assessing Exposures to Particulate Matter and Manganese in Welding Fumes

    E-Print Network [OSTI]

    LIU, SA

    2010-01-01

    helmets.   American Industrial Hygiene Association Journal welding.   American Industrial Hygiene Association Journal electrodes.  American  Industrial Hygiene Association 

  2. Ion source based on the cathodic arc

    DOE Patents [OSTI]

    Sanders, D.M.; Falabella, S.

    1994-02-01

    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.

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

    SciTech Connect (OSTI)

    Li, Leijun

    2012-11-02

    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.

  4. Phase transformation and mechanical behavior in annealed 2205 duplex stainless steel welds

    SciTech Connect (OSTI)

    Badji, Riad Bouabdallah, Mabrouk; Bacroix, Brigitte; Kahloun, Charlie; Belkessa, Brahim; Maza, Halim

    2008-04-15

    The phase transformations and mechanical behaviour during welding and subsequent annealing treatment of 2205 duplex stainless steel have been investigated. Detailed microstructural examination showed the presence of higher ferrite amounts in the heat affected zone (HAZ), while higher amounts of austenite were recorded in the centre region of the weld metal. Annealing treatments in the temperature range of 800-1000 deg. C resulted in a precipitation of {sigma} phase and M{sub 23}C{sub 6} chromium carbides at the {gamma}/{delta} interfaces that were found to be preferential precipitation sites. Above 1050 deg. C, the volume fraction of {delta} ferrite increases with annealing temperature. The increase of {delta} ferrite occurs at a faster rate in the HAZ than in the base metal and fusion zone. Optimal mechanical properties and an acceptable ferrite/austenite ratio throughout the weld regions corresponds to annealing at 1050 deg. C. Fractographic examinations showed that the mode of failure changed from quasi-cleavage fracture to dimple rupture with an increase in the annealing temperature from 850 to 1050 deg. C.

  5. Modelling of Mechanical Properties of Ferritic Weld Metals

    E-Print Network [OSTI]

    Lalam, Sree Harsha

    2000-12-05

    #6;K\\H^]_Q`LWN#19;BZKaHZKMb`L#19;KMKcQ`]edcQgfhN#6;Q`LiQ`]kjWBIDGlGQTF#6;Q`mEBon#4;OPNpN#19;BZKcqaSIDRr`KMLJFJDRNsn Q`]#17;tiO`[#17;YILJDGHIb`K`u#15;ACBZKvL#19;K\\F#6;K\\OPLJfwB#8;HIK\\F#19;fhLJDRYxK\\HyBZKMLJK\\DGSyziO`F{fhQTSIHIXIfhN#6;K\\H#8;XISIHZKML... |N#19;BZKvFJXZmxKML#19;r}DVF#19;DRQTS~Q`] j#21;LJQ`]K\\F#19;F#19;Q`LC?uI?^uId#4;uI?#17;uI?iBIO`HZK\\F#19;BIDVO#4;DVS|N#19;BIK?dcKMm OPL#19;N#19;[^K\\SoNCQ`]#23;?vOPN#6;KMLJDGO`lGFa?gfMDRK\\SIfhK3O`SIH&?=KMN#19;O`lGlGXZLJb`n`? qaSIDRr`KMLJF#19;DGNsn?Q`]?ti...

  6. Measurement of Plastic Strain Distribution in Dissimilar Metal Weld by

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(JournalspectroscopyReport) | SciTech ConnectnonlinearityConnect

  7. Personalized Online Education --A Crowdsourcing Challenge Daniel S. Weld1

    E-Print Network [OSTI]

    Mausam

    Personalized Online Education -- A Crowdsourcing Challenge Daniel S. Weld1 Eytan Adar2 Lydia- chanical Turk, may prove useful for optimizing personalized curricula (Dai, Mausam, and Weld 2010; Shahaf and Horvitz 2010; Dai, Mausam, and Weld 2011; Lin, Mausam, and Copyright c 2012, Association

  8. Temporal Information Extraction Xiao Ling and Daniel S. Weld

    E-Print Network [OSTI]

    Temporal Information Extraction Xiao Ling and Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195-2350, U.S.A. {xiaoling, weld- supervised probabilistic sequential models (Banko et al. 2007; Wu and Weld 2007), and numerous other ap

  9. REAL TIME ULTRASONIC ALUMINUM SPOT WELD MONITORING SYSTEM

    SciTech Connect (OSTI)

    Regalado, W. Perez; Chertov, A. M.; Maev, R. Gr. [Institute for Diagnostic Imaging Research, Physics Department, University of Windsor, 292 Essex Hall, 401 Sunset Ave. N9B 3P4 Windsor, Ontario (Canada)

    2010-02-22

    Aluminum alloys pose several properties that make them one of the most popular engineering materials: they have excellent corrosion resistance, and high weight-to-strength ratio. Resistance spot welding of aluminum alloys is widely used today but oxide film and aluminum thermal and electrical properties make spot welding a difficult task. Electrode degradation due to pitting, alloying and mushrooming decreases the weld quality and adjustment of parameters like current and force is required. To realize these adjustments and ensure weld quality, a tool to measure weld quality in real time is required. In this paper, a real time ultrasonic non-destructive evaluation system for aluminum spot welds is presented. The system is able to monitor nugget growth while the spot weld is being made. This is achieved by interpreting the echoes of an ultrasound transducer located in one of the welding electrodes. The transducer receives and transmits an ultrasound signal at different times during the welding cycle. Valuable information of the weld quality is embedded in this signal. The system is able to determine the weld nugget diameter by measuring the delays of the ultrasound signals received during the complete welding cycle. The article presents the system performance on aluminum alloy AA6022.

  10. APPLICATION OF MILLISECOND PULSED LASER WELDING IN MEMS P. Bozorgi*

    E-Print Network [OSTI]

    MacDonald, Noel C.

    APPLICATION OF MILLISECOND PULSED LASER WELDING IN MEMS PACKAGING P. Bozorgi* , C.B. Burgner, Z:YAG pulsed laser is used as a localized heating source to micro-weld a 350 µm titanium cap to the substrate distortion of the welding, several geometries at the cap and substrate interface were investigated

  11. CORRECTION OF BUTT-WELDING INDUCED DISTORTIONS BY LASER FORMING

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    CORRECTION OF BUTT-WELDING INDUCED DISTORTIONS BY LASER FORMING Peng Cheng, Andrew J. Birnbaum, Y Egland Technology and Solutions Division Caterpillar Inc. Peoria, IL KEYWORDS Welding, Distortion, Correction, Laser Forming ABSTRACT Welding-induced distortion is an intrinsic phenomenon arising due

  12. Conformal welding and the sewing equations Eric Schippers

    E-Print Network [OSTI]

    Schippers, Eric

    Conformal welding and the sewing equations Eric Schippers Department of Mathematics University of Manitoba Winnipeg Rutgers 2014 Eric Schippers (Manitoba) Conformal welding Rutgers 1 / 41 #12;Introduction Schippers (Manitoba) Conformal welding Rutgers 2 / 41 #12;Introduction Our work in general We began

  13. CONFORMAL WELDING AND KOEBE'S THEOREM CHRISTOPHER J. BISHOP

    E-Print Network [OSTI]

    Bishop, Christopher

    CONFORMAL WELDING AND KOEBE'S THEOREM CHRISTOPHER J. BISHOP Abstract. It is well known that not every orientation preserving homeomorphism of the circle to itself is a conformal welding, but in this paper we prove several results which state that every homeomorphism is \\almost" a welding in a precise

  14. Lithium-Assisted Electrochemical Welding in Silicon Nanowire Battery Electrodes

    E-Print Network [OSTI]

    Li, Teng

    Lithium-Assisted Electrochemical Welding in Silicon Nanowire Battery Electrodes Khim Karki, Eric of lithium- assisted welding between physically contacted silicon nano- wires (SiNWs) induced by electrochemical lithiation and delithiation. This electrochemical weld between two SiNWs demonstrates facile

  15. Minimization of welding residual stress and distortion in large structures

    E-Print Network [OSTI]

    Michaleris, Panagiotis

    1 Minimization of welding residual stress and distortion in large structures P. Michaleris at Champaign Urbana, Urbana, IL Abstract Welding distortion in large structures is usually caused by buckling due to the residual stress. In cases where the design is fixed and minimum weld size requirements

  16. In-situ Characterization of Titanium Laser Welding Vincent Fays

    E-Print Network [OSTI]

    Psaltis, Demetri

    In-situ Characterization of Titanium Laser Welding Vincent Fays Supervisors: M.Leparoux1, J here is a preliminary work on titanium laser welding. Its main objective is to investigate of correlation could be drawn between the characterization measurements and the weld quality. In order to do so

  17. Apparatus for the concurrent inspection of partially completed welds

    DOE Patents [OSTI]

    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)

    2002-01-01

    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.

  18. Connecting ARC/INFO and SNACTor Project Report

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    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

  19. A study of vacuum arc ion velocities using a linear set of probes

    E-Print Network [OSTI]

    Hohenbild, Stefan

    2008-01-01

    method; aluminum plasma; arc current constant at 200 A.velocity in vacuum arc plasmas by arc current perturbationin the vicinity of the arc plasma source. submitted to J.

  20. Ion flux from vacuum arc cathode spots in the absence and presence of a magnetic field

    E-Print Network [OSTI]

    Anders, Andre; Yushkov, George Yu.

    2001-01-01

    velocity in vacuum arc plasmas by arc current perturbation,field increases the plasma impedance, arc burning voltage,is well-known that the vacuum arc plasma is produced at non-

  1. A Summary of Recent Experimental Research on Ion Energy and Charge States of Pulsed Vacuum Arcs

    SciTech Connect (OSTI)

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

    2008-06-16

    The paper reviews the results of vacuum arc experimental investigations made collaboratively by research groups from Berkeley and Tomsk over the last two years, i.e. since the last ISDEIV in 2006. Vacuum arc plasma of various metals was produced in pulses of a few hundred microseconds duration, and the research focussed on three topics: (i) the energy distribution functions for different ion charge states, (ii) the temporal development of the ion charge state distribution, and (iii) the evolution of the mean directed ion velocities during plasma expansion. A combined quadruple mass-to-charge and energy ana-lyzer (EQP by HIDEN Ltd) and a time-of-flight spectrometer were employed. Cross-checking data by those complimen-tary techniques helped to avoid possible pitfalls in interpre-tation. It was found that the ion energy distribution func-tions in the plasma were independent of the ion charge state, which implies that the energy distribution on a substrate are not equal to due to acceleration in the substrate's sheath. In pulsed arc mode, the individual ion charge states fractions showed changes leading to a decrease of the mean charge state toward a steady-state value. This decrease can be re-duced by lower arc current, higher pulse repetition rate and reduced length of the discharge gap. It was also found that the directed ion velocity slightly decreased as the plasma expanded into vacuum.

  2. Modeling rf breakdown arcs II: plasma / materials interactions

    E-Print Network [OSTI]

    Insepov, Zeke; Proslier, Thomas; Mahalingam, Sudhakar; Veitzer, S

    2010-01-01

    Continuing the description of rf vacuum arcs from an earlier paper, we describe some aspects of the interaction of vacuum arcs that involve the surface. This paper describes aspects of plasma materials interactions that affect the arc and models measurement of the surface field using the Tonks-Frenkel and the spinodal electrohydrodynamic instabilities, a realistic model for the generation and evaluation of high field enhancements, unipolar arcs, creep and other effects.

  3. Ultrasonic Spot Welding of AZ31B to Galvanized Mild Steel

    SciTech Connect (OSTI)

    Pan, Dr. Tsung-Yu; Franklin, Teresa; Pan, Professor Jwo; Brown, Elliot; Santella, Michael L

    2010-01-01

    Ultrasonic spot welds were made between sheets of 0.8-mm-thick hot-dip-galvanized mild steel and 1.6-mm-thick AZ31B-H24. Lap-shear strengths of 3.0-4.2 kN were achieved with weld times of 0.3-1.2 s. Failure to achieve strong bonding of joints where the Zn coating was removed from the steel surface indicate that Zn is essential to the bonding mechanism. Microstructure characterization and microchemical analysis indicated temperatures at the AZ31-steel interfaces reached at least 344 C in less than 0.3 s. The elevated temperature conditions promoted annealing of the AZ31-H24 metal and chemical reactions between it and the Zn coating.

  4. Understanding the solidification and microstructure evolution during CSC-MIG welding of Fe–Cr–B-based alloy

    SciTech Connect (OSTI)

    Sorour, A.A. Chromik, R.R. Gauvin, R. Jung, I.-H. Brochu, M.

    2013-12-15

    The present is a study of the solidification and microstructure of Fe–28.2%Cr–3.8%B–1.5%Si–1.5%Mn (wt.%) alloy deposited onto a 1020 plain carbon steel substrate using the controlled short-circuit metal inert gas welding process. The as-solidified alloy was a metal matrix composite with a hypereutectic microstructure. Thermodynamic calculation based on the Scheil–Gulliver model showed that a primary (Cr,Fe){sub 2}B phase formed first during solidification, followed by an eutectic formation of the (Cr,Fe){sub 2}B phase and a body-centered cubic Fe-based solid solution matrix, which contained Cr, Mn and Si. Microstructure analysis confirmed the formation of these phases and showed that the shape of the (Cr,Fe){sub 2}B phase was irregular plate. As the welding heat input increased, the weld dilution increased and thus the volume fraction of the (Cr,Fe){sub 2}B plates decreased while other microstructural characteristics were similar. - Highlights: • We deposit Fe–Cr–B-based alloy onto plain carbon steel using the CSC-MIG process. • We model the solidification behavior using thermodynamic calculation. • As deposited alloy consists of (Cr,Fe){sub 2}B plates embedded in Fe-based matrix. • We study the effect of the welding heat input on the microstructure.

  5. Actively controlled vibration welding system and method

    DOE Patents [OSTI]

    Cai, Wayne W.; Kang, Bongsu; Tan, Chin-An

    2013-04-02

    A vibration welding system includes a controller, welding horn, an active material element, and anvil assembly. The assembly may include an anvil body connected to a back plate and support member. The element, e.g., a piezoelectric stack or shape memory alloy, is positioned with respect to the assembly. The horn vibrates in a desirable first direction to form a weld on a work piece. The element controls any vibrations in a second direction by applying calibrated response to the anvil body in the second direction. A method for controlling undesirable vibrations in the system includes positioning the element with respect to the anvil assembly, connecting the anvil body to the support member through the back plate, vibrating the horn in a desirable first direction, and transmitting an input signal to the element to control vibration in an undesirable second direction.

  6. Weld overlay coatings for erosion control

    SciTech Connect (OSTI)

    Levin, B.; DuPont, J.N.; Marder, A.R.

    1993-03-03

    A literature review was made. In spite of similarities between abrasive wear and solid particle erosion, weld overlay hardfacing alloys that exhibit high abrasion resistance may not necessarily have good erosion resistance. The performance of weld overlay hardfacing alloys in erosive environments has not been studied in detail. It is believed that primary-solidified hard phases such as carbides and intermetallic compounds have a strong influence on erosion resistance of weld overlay hardfacing alloys. However, relationships between size, shape, and volume fraction of hard phases in a hardfacing alloys and erosion resistance were not established. Almost all hardfacing alloys can be separated into two major groups based upon chemical compositions of the primary solidified hard phases: (a) carbide hardening alloys (Co-base/carbide, WC-Co and some Fe base superalloys); and (b) intermetallic hardening alloys (Ni-base alloys, austenitic steels, iron-aluminides).

  7. Innovative Flash Control in Inertia Welding

    SciTech Connect (OSTI)

    Korinko, P.S.

    2003-04-25

    Inertia welding is widely used to join cylindrically shaped objects such as disks and shafts in turbine engines, turbochargers, etc. Flash control in many of these applications is not critical because the excess material is on external surfaces and can readily be removed by machining. Internal flash on hollow vessels, however, may be difficult or impossible to remove and may be either controlled by the use of flash traps or the part can be used as welded. Both internal flash and flash traps reduce internal volume and the conditions are not always acceptable. To address this short-coming, several innovative methods have been tested to determine their effect on flash control in inertia welding of hollow vessels. The methods include introduction of high pressure inert gas and incorporation of an expendable mandrel to divert the flash. Both gas and internal mandrels appear promising methods for diverting flash.

  8. Pairing, pseudogap and Fermi arcs in cuprates

    SciTech Connect (OSTI)

    Kaminski, Adam; Gu, Genda; Kondo, Takeshi; Takeuchi, Tsunehiro

    2014-04-29

    We use Angle Resolved Photoemission Spectroscopy (ARPES) to study the relationship between the pseudogap, pairing and Fermi arcs in cuprates. High quality data measured over a wide range of dopings reveals a consistent picture of Fermiology and pairing in these materials. The pseudogap is due to an ordered state that competes with superconductivity rather than preformed pairs. Pairing does occur below Tpair ~ 150K and significantly above Tc, but well below T* and the doping dependence of this temperature scale is distinct from that of the pseudogap. The d-wave gap is present below Tpair, and its interplay with strong scattering creates “artificial” Fermi arcs for Tc < T < Tpair. However, above Tpair, the pseudogap exists only at the antipodal region. This leads to presence of real, gapless Fermi arcs close to the node. The length of these arcs remains constant up to T*, where the full Fermi surface is recovered. We demonstrate that these findings resolve a number of seemingly contradictory scenarios.

  9. Remote electrical arc suppression by laser filamentation

    E-Print Network [OSTI]

    Schubert, Elise; Kasparian, Jérôme; Wolf, Jean-Pierre

    2015-01-01

    We investigate the interaction of narrow plasma channels formed in the filamentation of ultrashort laser pulses, with a DC high voltage. The laser filaments prevent electrical arcs by triggering corona that neutralize the high-voltage electrodes. This phenomenon, due to the electric field modulation and free electron release around the filament, opens new prospects to lightning and over-voltage mitigation.

  10. Pairing, pseudogap and Fermi arcs in cuprates

    SciTech Connect (OSTI)

    Kaminski, Adam [Iowa State Univ., Ames, IA (United States); Gu, Genda [Brookhaven National Lab. (BNL), Upton, NY (United States); Kondo, Takeshi [The Univ. of Tokyo, Chiba (Japan); Takeuchi, Tsunehiro [Nagoya Univ., Nagoya (Japan)

    2014-10-31

    We use Angle Resolved Photoemission Spectroscopy (ARPES) to study the relationship between the pseudogap, pairing and Fermi arcs in cuprates. High quality data measured over a wide range of dopings reveals a consistent picture of Fermiology and pairing in these materials. The pseudogap is due to an ordered state that competes with superconductivity rather than preformed pairs. Pairing does occur below Tpair ~ 150K and significantly above Tc, but well below T* and the doping dependence of this temperature scale is distinct from that of the pseudogap. The d-wave gap is present below Tpair, and its interplay with strong scattering creates “artificial” Fermi arcs for Tc < T < Tpair. However, above Tpair, the pseudogap exists only at the antipodal region. This leads to presence of real, gapless Fermi arcs close to the node. The length of these arcs remains constant up to T*, where the full Fermi surface is recovered. We demonstrate that these findings resolve a number of seemingly contradictory scenarios.

  11. Exploring the Deep... Using ArcMap

    E-Print Network [OSTI]

    Wright, Dawn Jeannine

    started Exploring the Ocean Environment Introduction #12;The ArcMap User Interface Table of Contents off the layers above that layer in the Table of Contents. Table of Contents A list of data frames of the current map file. Coordinates Displays the coordinates, in the currently-selected units, of the cursor

  12. Energy Savings in Electric Arc Furnace Melting 

    E-Print Network [OSTI]

    Lubbeck, W.

    1982-01-01

    Arc furnace melting which at one time was almost exclusively used to produce alloy steel and steel castings is now widely accepted in the industry as an efficient process to produce all types of steel and iron. Presently, about 28% of steel...

  13. Pairing, pseudogap and Fermi arcs in cuprates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kaminski, Adam; Kondo, Takeshi; Takeuchi, Tsunehiro; Gu, Genda

    2014-04-29

    We use Angle Resolved Photoemission Spectroscopy (ARPES) to study the relationship between the pseudogap, pairing and Fermi arcs in cuprates. High quality data measured over a wide range of dopings reveals a consistent picture of Fermiology and pairing in these materials. The pseudogap is due to an ordered state that competes with superconductivity rather than preformed pairs. Pairing does occur below Tpair ~ 150K and significantly above Tc, but well below T* and the doping dependence of this temperature scale is distinct from that of the pseudogap. The d-wave gap is present below Tpair, and its interplay with strong scatteringmore »creates “artificial” Fermi arcs for Tc ? T ? Tpair. However, above Tpair, the pseudogap exists only at the antipodal region. This leads to presence of real, gapless Fermi arcs close to the node. The length of these arcs remains constant up to T*, where the full Fermi surface is recovered. As a result, we demonstrate that these findings resolve a number of seemingly contradictory scenarios.« less

  14. Theory of the arc discharge in air blast breakers

    SciTech Connect (OSTI)

    Vogel, H.F.

    1980-08-01

    The complete set of equations obtaining in the arc's length element are given. The arc length is determined when the external circuit equations are closed by an expression for the arc inductance as a function of the radius and length, in addition to our relationships for the radius and voltage gradients.

  15. Driven Motion and Instability of an Atmospheric Pressure Arc

    E-Print Network [OSTI]

    of equilibrium and stability of such arcs, an experimental arc furnace is constructed and operated in air. Applicability of the results of the thesis to an industrial steelmaking furnace is considered. iv #12; Dedicated am very thankful to Lane Roquemore for helping get the Arc Furnace o# the ground and for his

  16. PYROLYSIS OF METHANE IN A SUPERSONIC, ARC-HEATED FLOW

    E-Print Network [OSTI]

    Texas at Arlington, University of

    1 PYROLYSIS OF METHANE IN A SUPERSONIC, ARC-HEATED FLOW F.K. Lu,* C.M. Roseberry, J.M. Meyers and D arc pyrolysis of methane at supersonic conditions, representative of conditions in the reformer location of an aibreathing hypersonic vehicle. The rationale for arc pyrolysis is provided. Major

  17. INSTRUCTIONS FOR USING ARCVIEW ArcViewsoftwareisavailableintheUTSLab,

    E-Print Network [OSTI]

    Thompson, Michael

    SciencesBuilding,Room241and in Mills Library, Gateway Data/GIS Lab, Room 111A. Arc the ArcView GIS icon. If you are in the Map Collection or the Gateway Data/GIS Lab: Before starting copy of the data files.) Select Start. Select Programs. Select ArcView GIS. If your first screen does

  18. Results of crack-arrest tests on two irradiated high-copper welds

    SciTech Connect (OSTI)

    Iskander, S.K.; Corwin, W.R.; Nanstead, R.K. (Oak Ridge National Lab., TN (USA))

    1990-12-01

    The objective of this study was to determine the effect of neutron irradiation on the shift and shape of the lower-bound curve to crack-arrest data. Two submerged-arc welds with copper contents of 0.23 and 0.31 wt % were commercially fabricated in 220-mm-thick plate. Crack-arrest specimens fabricated from these welds were irradiated at a nominal temperature of 288{degree}C to an average fluence of 1.9 {times} 10{sup 19} neutrons/cm{sup 2} (>1 MeV). Evaluation of the results shows that the neutron-irradiation-induced crack-arrest toughness temperature shift is about the same as the Charpy V-notch impact temperature shift at the 41-J energy level. The shape of the lower-bound curves (for the range of test temperatures covered) did not seem to have been altered by irradiation compared to those of the ASME K{sub Ia} curve. 9 refs., 21 figs., 10 tabs.

  19. Aplicaciones de Arc GISAplicaciones de Arc GIS en Recursos de Aguaen Recursos de Agua

    E-Print Network [OSTI]

    Gilbes, Fernando

    Aplicaciones de Arc GISAplicaciones de Arc GIS en Recursos de Aguaen Recursos de Agua Alejandra 14: 440 personas/km2 vrs India y Japón 338vrs India y Japón 338 perper/km2./km2. El uso del agua se ha incrementado un 1.6% de 1970 aEl uso del agua se ha incrementado un 1.6% de 1970 a 1995 con 2

  20. Method and apparatus for welding precipitation hardenable materials

    DOE Patents [OSTI]

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

    1994-01-01

    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.

  1. Method and apparatus for welding precipitation hardenable materials

    DOE Patents [OSTI]

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

    1994-06-28

    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.

  2. Residual Stress Measurements in Side Bonded Resistance Welds

    SciTech Connect (OSTI)

    PAUL, KORINKO

    2005-04-18

    Resistance upset welding is used to attach small diameter machined tubes to small gas vessels. Recently there has been interest in determining the level of residual stresses caused by this attachment method and its influence on environmental interactions. A test program was initiated to determine the residual stresses present due to welding using the nominal weld parameters and varying the interference between the foot and the counter bore. In this paper, the residual stress measurement technique is described, the welding conditions are provided, and the residual stress due to welding at the nominal conditions are presented.

  3. Numerical investigation of the double-arcing phenomenon in a cutting arc torch

    SciTech Connect (OSTI)

    Mancinelli, B. R.; Minotti, F. O.; Kelly, H.; Prevosto, L.

    2014-07-14

    A numerical investigation of the double-arcing phenomenon in a cutting arc torch is reported. The dynamics of the double-arcing were simulated by using a two-dimensional model of the gas breakdown development in the space-charge layer contiguous to the nozzle of a cutting arc torch operated with oxygen. The kinetic scheme includes ionization of heavy particles by electron impact, electron attachment, electron detachment, electron–ion recombination, and ion–ion recombination. Complementary measurements during double-arcing phenomena were also conducted. A marked rise of the nozzle voltage was found. The numerical results showed that the dynamics of a cathode spot at the exit of the nozzle inner surface play a key role in the raising of the nozzle voltage, which in turn allows more electrons to return to the wall at the nozzle inlet. The return flow of electrons thus closes the current loop of the double-arcing. The increase in the (floating) nozzle voltage is due to the fact that the increased electron emission at the spot is mainly compensated by the displacement current (the ions do not play a relevant role due to its low-mobility) until that the stationary state is achieved and the electron return flow fully-compensates the electron emission at the spot. A fairly good agreement was found between the model and the experiment for a spot emission current growth rate of the order of 7?×?10{sup 4}?A/s.

  4. Magnetized Cascade Arc Source forMagnetized Cascade Arc Source for Ionization and Fuelling in TCSUIonization and Fuelling in TCSU

    E-Print Network [OSTI]

    Washington at Seattle, University of

    , the arc source can also be run during FRC sustainment to provide steady state plasma fuelling. The deuterium plasma produced by the arc source is tied to the external axial magnetic field lines, providing and is used for initial breakdown and arc sustainment. Plasma densities of 1020 m-3 and electron temperatures

  5. Modeling of Heat and Mass Transfer in Fusion Welding

    SciTech Connect (OSTI)

    Zhang, Wei [ORNL

    2011-01-01

    In fusion welding, parts are joined together by melting and subsequent solidification. Although this principle is simple, complex transport phenomena take place during fusion welding, and they determine the final weld quality and performance. The heat and mass transfer in the weld pool directly affect the size and shape of the pool, the solidification microstructure, the formation of weld defects such as porosity and humping, and the temperature distribution in the fusion zone and heat-affected zone (HAZ). Furthermore, the temperature evolution affects the kinetics and extent of various solid-state phase transformations, which in turn determine the final weld microstructure and mechanical properties. The formation of residual stresses and distortion originates from the thermal expansion and contraction during welding heating and cooling, respectively.

  6. Friction Stir Spot Welding of DP780 Carbon Steel

    SciTech Connect (OSTI)

    Santella, M. L.; Hovanski, Yuri; Frederick, Alan; Grant, Glenn J.; Dahl, Michael E.

    2009-09-15

    Friction stir spot welds were made in uncoated and galvannneled DP780 sheets using polycrystalline boron nitride stir tools. The tools were plunged at either a single continuous rate or in two segments consisting of a relatively high rate followed by a slower rate of shorter depth. Welding times ranged from 1-10 s. Increasing tool rotation speed from 800 to 1600 rpm increased strength values. The 2-segment welding procedures also produced higher strength joints. Average lap-shear strengths exceeding 10.3 kN were consistently obtained in 4 s on both the uncoated and the galvannealed DP780. The likelihood of diffusion and mechanical interlocking contributing to bond formation was supported by metallographic examinations. A cost analysis based on spot welding in automobile assembly showed that for friction stir spot welding to be economically competitive with resistance spot welding the cost of stir tools must approach that of resistance spot welding electrode tips.

  7. Method for the concurrent ultrasonic inspection of partially completed welds

    DOE Patents [OSTI]

    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)

    2002-01-01

    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.

  8. Tubular hydrogen permeable metal foil membrane and method of fabrication

    DOE Patents [OSTI]

    Paglieri, Stephen N.; Birdsell, Stephen A.; Barbero, Robert S.; Snow, Ronny C.; Smith, Frank M.

    2006-04-04

    A tubular hydrogen permeable metal membrane and fabrication process comprises obtaining a metal alloy foil having two surfaces, coating the surfaces with a metal or metal alloy catalytic layer to produce a hydrogen permeable metal membrane, sizing the membrane into a sheet with two long edges, wrapping the membrane around an elongated expandable rod with the two long edges aligned and overlapping to facilitate welding of the two together, placing the foil wrapped rod into a surrounding fixture housing with the two aligned and overlapping foil edges accessible through an elongated aperture in the surrounding fixture housing, expanding the elongated expandable rod within the surrounding fixture housing to tighten the foil about the expanded rod, welding the two long overlapping foil edges to one another generating a tubular membrane, and removing the tubular membrane from within the surrounding fixture housing and the expandable rod from with the tubular membrane.

  9. Characteristic of a triple-cathode vacuum arc plasma source

    SciTech Connect (OSTI)

    Xiang, W.; Li, M.; Chen, L.

    2012-02-15

    In order to generate a better ion beam, a triple-cathode vacuum arc plasma source has been developed. Three plasma generators in the vacuum arc plasma source are equally located on a circle. Each generator initiated by means of a high-voltage breakdown between the cathode and the anode could be operated separately or simultaneously. The arc plasma expands from the cathode spot region in vacuum. In order to study the behaviors of expanding plasma plume generated in the vacuum arc plasma source, a Langmuir probe array is employed to measure the saturated ion current of the vacuum arc plasma source. The time-dependence profiles of the saturated current density of the triple vacuum arc plasma source operated separately and simultaneously are given. Furthermore, the plasma characteristic of this vacuum arc plasma source is also presented in the paper.

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anders, Andre

    2014-10-01

    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.

  11. Ion Species and Charge States of Vacuum Arc Plasma with Gas Feed and Longitudinal Magnetic Field

    SciTech Connect (OSTI)

    Oks, Efim; Anders, Andre

    2010-06-23

    The evolution of copper ion species and charge state distributions is measured for a long vacuum arc discharge plasma operated in the presence of a longitudinal magnetic field of several 10 mT and working gas (Ar). It was found that changing the cathode-anode distance within 20 cm as well as increasing the gas pressure did not affect the arc burning voltage and power dissipation by much. In contrast, burning voltage and power dissipation were greatly increased as the magnetic field was increased. The longer the discharge gap the greater was the fraction of gaseous ions and the lower the fraction of metal ions, while the mean ion charge state was reduced. It is argued that the results are affected by charge exchange collisions and electron impact ionization.

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

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Anders, André

    2014-09-02

    In this study, 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 thismore »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.« less

  13. Integrated optical sensor

    DOE Patents [OSTI]

    Watkins, Arthur D. (Idaho Falls, ID); Smartt, Herschel B. (Idaho Falls, ID); Taylor, Paul L. (Idaho Falls, ID)

    1994-01-01

    An integrated optical sensor for arc welding having multifunction feedback control. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties.

  14. Integrated optical sensor

    DOE Patents [OSTI]

    Watkins, A.D.; Smartt, H.B.; Taylor, P.L.

    1994-01-04

    An integrated optical sensor for arc welding having multifunction feedback control is described. The sensor, comprising generally a CCD camera and diode laser, is positioned behind the arc torch for measuring weld pool position and width, standoff distance, and post-weld centerline cooling rate. Computer process information from this sensor is passed to a controlling computer for use in feedback control loops to aid in the control of the welding process. Weld pool position and width are used in a feedback loop, by the weld controller, to track the weld pool relative to the weld joint. Sensor standoff distance is used in a feedback loop to control the contact tip to base metal distance during the welding process. Cooling rate information is used to determine the final metallurgical state of the weld bead and heat affected zone, thereby controlling post-weld mechanical properties. 6 figures.

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

    SciTech Connect (OSTI)

    Dai, Z. R. Crowhurst, J. C.; Grant, C. D.; Knight, K. B.; Tang, V.; Chernov, A. A.; Cook, E. G.; Lotscher, J. P.; Hutcheon, I. D.

    2013-11-28

    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.

  16. Electrical Safety and Arc Flash Protections

    SciTech Connect (OSTI)

    R. Camp

    2008-03-04

    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.

  17. Filtered cathodic arc deposition apparatus and method

    DOE Patents [OSTI]

    Krauss, Alan R. (24461 W. Blvd. De John, Naperville, IL 60564)

    1999-01-01

    A filtered cathodic arc deposition method and apparatus for the production of highly dense, wear resistant coatings which are free from macro particles. The filtered cathodic arc deposition apparatus includes a cross shaped vacuum chamber which houses a cathode target having an evaporable surface comprised of the coating material, means for generating a stream of plasma, means for generating a transverse magnetic field, and a macro particle deflector. The transverse magnetic field bends the generated stream of plasma in the direction of a substrate. Macro particles are effectively filtered from the stream of plasma by traveling, unaffected by the transverse magnetic field, along the initial path of the plasma stream to a macro particle deflector. The macro particle deflector has a preformed surface which deflects macro particles away from the substrate.

  18. Cathodic Vacuum Arc Plasma of Thallium

    SciTech Connect (OSTI)

    Yushkov, Georgy Yu.; Anders, Andre

    2006-10-02

    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.

  19. Effect of Nd:YAG laser welding on microstructure and hardness of an Al-Li based alloy

    SciTech Connect (OSTI)

    Cui, Li, E-mail: cuili@bjut.edu.cn [Beijing University of Technology (China)] [Beijing University of Technology (China); Li, Xiaoyan, E-mail: xyli@bjut.edu.cn [Beijing University of Technology (China)] [Beijing University of Technology (China); He, Dingyong, E-mail: dyhe@bjut.edu.cn [Beijing University of Technology (China)] [Beijing University of Technology (China); Chen, Li, E-mail: ouchenxi@163.com [AVIC Beijing Aeronautical Manufacturing Technology Research Institute (China)] [AVIC Beijing Aeronautical Manufacturing Technology Research Institute (China); Gong, Shuili, E-mail: gongshuili@sina.com [AVIC Beijing Aeronautical Manufacturing Technology Research Institute (China)] [AVIC Beijing Aeronautical Manufacturing Technology Research Institute (China)

    2012-09-15

    Butt joints of 3.0 mm thick sheets of an Al-Li based alloy have been produced using Nd:YAG laser welding without filler metals. The hardness distribution and microstructure of the alloy and welded joints were investigated. The changes in the grain shapes, grain orientations, microtexture, and precipitates of the fusion zone were analyzed using optical microscope, electron back scattered diffraction (EBSD) and transmission electron microscopy (TEM). The results show that Nd:YAG laser welding leads to a change of the microhardness, grain shape, grain orientations, and a disappearance of the microtexture and precipitates. A narrow band of EQZ along the fusion boundary and a predominantly equiaxed dendritic structure are developed in the fusion zone. The formation of the predominately equiaxed dendritic grains is due to a heterogeneous nucleation mechanism aided by equilibrium A1{sub 3}Zr phases as well as the growth of pre-existing nuclei created by dendrite fragmentation, or by grain detachment resulted from Nd:YAG laser welding processes. In addition, Nd:YAG laser welding produces lower Vickers hardness than that of the base metal due to the decrease in the in quantity of {delta} Prime precipitates in the fusion zone. - Graphical Abstract: The grain shapes, grain orientations, microtexture, and precipitates of the solidified fusion zone were investigated and compared with the base metal using optical microscope, electron back scattered diffraction (EBSD) and transmission electron microscope (TEM). EBSD orientation map of laser welded joint in 5A90 alloys is presented in Fig. 3. It clearly shows that a narrow band EQZ along the fusion boundary and the predominantly equiaxed grains have been developed in the fusion zone of 5A90 alloys. Also, it is clear that the microstructure of the base metal is characterized by laminated grains with preferred orientations, whereas the fusion zone is predominately equiaxed grains in different colors having random orientations. Highlights: Black-Right-Pointing-Pointer The predominantly equiaxed dendritic structure is developed in the fusion zone. Black-Right-Pointing-Pointer The fusion zone with equiaxed grains shows random orientations and microtexture. Black-Right-Pointing-Pointer The loss in hardness in the fusion zone is due to the decrease in {delta} Prime precipitates. Black-Right-Pointing-Pointer The non-epitaxial growth occurs at fusion boundary. Black-Right-Pointing-Pointer The equilibrium A1{sub 3}Zr phases maybe the nuclei of new grains in the fusion zone.

  20. Volumetric modulated arc radiotherapy for esophageal cancer

    SciTech Connect (OSTI)

    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)

    2012-04-01

    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.

  1. EFFECTS OF WELDING ON WELDMENT MECHANICAL PERFORMANCE IN TWO AUSTENITIC STEELS

    E-Print Network [OSTI]

    Strum, M.J.

    2010-01-01

    Progress, Jan. 1979, p. 76. Welding Journal, June 1976, p .G.A. Ratz: Aug. 1968. C. Syn, Welding Research Council (WRC)Thesis, LBL-9208, May 1979. Welding Journal, July 1971, p.

  2. Apparatus for the concurrent ultrasonic inspection of partially completed welds

    DOE Patents [OSTI]

    Johnson, John A. (Idaho Falls, ID)

    2000-01-01

    An apparatus for the concurrent nondestructive evaluation of partially completed welds is described and which is used in combination with an automated welder and which includes an ultrasonic signal generator mounted on the welder and which generates an ultrasonic signal which is directed toward one side of the partially completed welds; an ultrasonic signal receiver mounted on the automated welder for detecting ultrasonic signals which are transmitted by the ultrasonic signal generator and which are reflected or diffracted from one side of the partially completed weld or which passes through a given region of the partially completed weld; and an analysis assembly coupled with the ultrasonic signal receiver and which processes the ultrasonic signals received by the ultrasonic signal receiver to identify welding flaws in the partially completed weld.

  3. Effect of Pulsed Nd: YAG Laser Powers On 304 Stainless Steel Welding

    SciTech Connect (OSTI)

    Candan, L.; Demir, A.; Akman, E. [University of Kocaeli, Laser Technologies Research and Application Center, Kocaeli (Turkey)

    2007-04-23

    In this study, optimum welding parameters are obtained for 1mm thickness type 304 stainless steel welding using the Lumonics JK760TR pulsed Nd:YAG laser. The influences of laser welding parameters such as pulse duration, focal position, frequency, laser power, welding speed, and shielding gas (N2) pressure on penetration defining welding quality are investigated. Also comparisons of overlap ratios are presented between theory and experiment for pulse duration, frequency and welding speed.

  4. Heat-affected zone liquation crack on resistance spot welded TWIP steels

    SciTech Connect (OSTI)

    Saha, Dulal Chandra [Department of Advanced Materials Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of); Chang, InSung [Automotive Production Development Division, Hyundai Motor Company (Korea, Republic of); Park, Yeong-Do, E-mail: ypark@deu.ac.kr [Department of Advanced Materials Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of)

    2014-07-01

    In this study, the heat affected zone (HAZ) liquation crack and segregation behavior of the resistance spot welded twinning induced plasticity (TWIP) steel have been reported. Cracks appeared in the post-welded joints that originated at the partially melted zone (PMZ) and propagated from the PMZ through the heat affected zone (HAZ) to the base metal (BM). The crack length and crack opening widths were observed increasing with heat input; and the welding current was identified to be the most influencing parameter for crack formation. Cracks appeared at the PMZ when nugget diameter reached at 4.50 mm or above; and the liquation cracks were found to occur along two sides of the notch tip in the sheet direction rather than in the electrode direction. Cracks were backfilled with the liquid films which has lamellar structure and supposed to be the eutectic constituent. Co-segregation of alloy elements such as, C and Mn were detected on the liquid films by electron-probe microanalysis (EPMA) line scanning and element map which suggests that the liquid film was enrich of Mn and C. The eutectic constituent was identified by analyzing the calculated phase diagram along with thermal temperature history of finite element simulation. Preliminary experimental results showed that cracks have less/no significant effect on the static cross-tensile strength (CTS) and the tensile-shear strength (TSS). In addition, possible ways to avoid cracking were discussed. - Highlights: • The HAZ liquation crack during resistance spot welding of TWIP steel was examined. • Cracks were completely backfilled and healed with divorced eutectic secondary phase. • Co-segregation of C and Mn was detected in the cracked zone. • Heat input was the most influencing factor to initiate liquation crack. • Cracks have less/no significant effect on static tensile properties.

  5. An investigation of residual stress in welded joints 

    E-Print Network [OSTI]

    Moffat, William Hugh

    1951-01-01

    . flummery and Conclusions VII. '-. &uggested Procedure for I"uture Investigation 18 o i' VIII. ? . Ppendix IX. Bibliography LIST OP EIGURES Ro. Title Page 1. 'welded Plates snd Gptical Gage Used by Soulton and Martin ~ ~ 6 2. Dr. Rao~s Method... AN INVESTIGATION OF RESIDUAL STRESS IN WELDED JOINTS INTRODUCTION The object of the research reported in this paper was to investigate the magnitude of transverse and longi- tudial residual stress in a welded Joint. These are the stresses in a direction...

  6. Friction Stir Welding High Strength Low Alloy Steel using a Multilayer...

    Office of Scientific and Technical Information (OSTI)

    Friction Stir Welding High Strength Low Alloy Steel using a Multilayer Approach Citation Details In-Document Search Title: Friction Stir Welding High Strength Low Alloy Steel using...

  7. Fracture of welded aluminum thin-walled structures

    E-Print Network [OSTI]

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

    2006-01-01

    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. ...

  8. Weld monitor and failure detector for nuclear reactor system

    DOE Patents [OSTI]

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

    1987-01-01

    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.

  9. Fluid Flow Phenomena during Welding (Book) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    humped beads, finger penetration, and undercutting. Instabilities in the liquid film around the keyhole in electron beam and laser welds are responsible for the uneven...

  10. Subterranean barriers including at least one weld

    DOE Patents [OSTI]

    Nickelson, Reva A.; Sloan, Paul A.; Richardson, John G.; Walsh, Stephanie; Kostelnik, Kevin M.

    2007-01-09

    A subterranean barrier and method for forming same are disclosed, the barrier including a plurality of casing strings wherein at least one casing string of the plurality of casing strings may be affixed to at least another adjacent casing string of the plurality of casing strings through at least one weld, at least one adhesive joint, or both. A method and system for nondestructively inspecting a subterranean barrier is disclosed. For instance, a radiographic signal may be emitted from within a casing string toward an adjacent casing string and the radiographic signal may be detected from within the adjacent casing string. A method of repairing a barrier including removing at least a portion of a casing string and welding a repair element within the casing string is disclosed. A method of selectively heating at least one casing string forming at least a portion of a subterranean barrier is disclosed.

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

    SciTech Connect (OSTI)

    Babich, Ida L.; Boretskij, Viacheslav F.; Veklich, Anatoly N.

    2007-09-28

    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.

  12. Theory of Parabolic Arcs in Interstellar Scintillation Spectra

    E-Print Network [OSTI]

    James M. Cordes; Barney J. Rickett; Daniel R. Stinebring; William A. Coles

    2004-07-03

    Our theory relates the secondary spectrum, the 2D power spectrum of the radio dynamic spectrum, to the scattered pulsar image in a thin scattering screen geometry. Recently discovered parabolic arcs in secondary spectra are generic features for media that scatter radiation at angles much larger than the rms scattering angle. Each point in the secondary spectrum maps particular values of differential arrival-time delay and fringe rate (or differential Doppler frequency) between pairs of components in the scattered image. Arcs correspond to a parabolic relation between these quantities through their common dependence on the angle of arrival of scattered components. Arcs appear even without consideration of the dispersive nature of the plasma. Arcs are more prominent in media with negligible inner scale and with shallow wavenumber spectra, such as the Kolmogorov spectrum, and when the scattered image is elongated along the velocity direction. The arc phenomenon can be used, therefore, to constrain the inner scale and the anisotropy of scattering irregularities for directions to nearby pulsars. Arcs are truncated by finite source size and thus provide sub micro arc sec resolution for probing emission regions in pulsars and compact active galactic nuclei. Multiple arcs sometimes seen signify two or more discrete scattering screens along the propagation path, and small arclets oriented oppositely to the main arc persisting for long durations indicate the occurrence of long-term multiple images from the scattering screen.

  13. ArcSafe® with Pulsed Arrested Spark Discharge

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

    Form ArcSafe with Pulsed Arrested Spark Discharge &24; The world's only advanced electrical wiring diagnostic capable of detecting insulation defects in complex wiring systems...

  14. Arc-Fault Detector Algorithm Evaluation Method Utilizing Prerecorded...

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

    Electrical Code Article 690.11 requires photovoltaic systems on or penetrating a building to include a DC arc-fault protection device. In order to satisfy this...

  15. A Dynamic Traveling Salesman Problem with Stochastic Arc Costs

    E-Print Network [OSTI]

    Alejandro Toriello

    2012-08-31

    Aug 31, 2012 ... Abstract: We propose a dynamic traveling salesman problem (TSP) with stochastic arc costs motivated by applications, such as dynamic ...

  16. PV Arc Fault Detector Challenges Due to Module Frequency Response...

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

    This poster does not contain any proprietary or confidential information. Introduction PV system arc faults have led to a number of rooftop fires which have caused significant...

  17. Puzzling differences in bismuth and lead plasmas: evidence for the significant role of neutrals in cathodic vacuum arcs

    E-Print Network [OSTI]

    Anders, Andre; Yushkov, Georgy Yu.

    2007-01-01

    for Pb and Bi cathodic arc plasmas revealed unexpectedCathodic vacuum arc plasmas are generally considered to beand (iv) the condensing arc plasma itself, because non-

  18. Production of neutrals and their and effects on the ion charge states in cathodic vacuum arc plasmas

    E-Print Network [OSTI]

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

    2007-01-01

    states in cathodic vacuum arc plasmas André Anders a , EfimRussia Abstract Cathodic arc plasmas are considered fullybeen known that cathodic arc plasmas go through an initial

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

    E-Print Network [OSTI]

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

    2006-01-01

    in filtered aluminum vacuum arc plasmas were measured andI. INTRODUCTION Vacuum arc plasma is well known to be highlymeasured for vacuum arc plasmas. Aluminum plasma, for

  20. Mo-containing tetrahedral amorphous carbon deposited by dual filtered cathodic vacuum arc with selective pulsed bias voltage

    E-Print Network [OSTI]

    Pasaja, Nitisak; Sansongsiri, Sakon; Intasiri, Sawate; Vilaithong, Thiraphat; Anders, Andre

    2007-01-01

    filtered cathodic vacuum arc plasma sources with selectivedual filtered cathodic vacuum arc plasma sources operated inrepetitively pulsed vacuum arc plasma sources operating in

  1. Effect of ion mass and charge state on transport of vacuum ARC plasmas through a biased magnetic filter

    E-Print Network [OSTI]

    Byon, Eungsun; Kim, Jong-Kuk; Kwon, Sik-Chol; Anders, Andre

    2003-01-01

    G. Brown, "Transport of vacuum arc plasmas through magneticto rid cathodic arc plasma of macro- and nanoparticles: afrom cathodic arc plasmas," Surf. Coat. Technol. , vol. 133-

  2. Mo-containing tetrahedral amorphous carbon deposited by dual filtered cathodic vacuum arc with selective pulsed bias voltage

    E-Print Network [OSTI]

    Pasaja, Nitisak; Sansongsiri, Sakon; Anders, Andre; Vilaithong, Thiraphat; Intasiri, Sawate

    2006-01-01

    filtered cathodic vacuum arc plasma sources with selectiverepetitively pulsed vacuum arc plasma sources operating inthe pulse length from each arc plasma source. They concluded

  3. Electrical properties of a-C:Mo films produced by dual-cathode filtered cathodic arc plasma deposition

    E-Print Network [OSTI]

    Sansongsiri, Sakon

    2008-01-01

    cathode filtered cathodic arc plasma system. Fig. 2. Filmfiltered cathodic arc plasma deposition Sakon Sansongsiri a,filtered cathodic arc plasma deposition Sakon Sansongsiri a,

  4. Time-dependence ion charge state distributions of vacuum arcs: An interpretation involving atoms and charge exchange collisions

    E-Print Network [OSTI]

    Anders, Andre

    2004-01-01

    functions of vacuum arc plasmas," J. Appl. Phys. , vol. 93,distributions of vacuum arc plasmas: The origin of species,"energetic condensation of cathodic arc plasma. More detailed

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

    SciTech Connect (OSTI)

    Ivanov, A. A.; Belchenko, Yu. I.; Davydenko, V. I.; Novosibirsk State University, Novosibirsk ; Ivanov, I. A.; Kolmogorov, V. V.; Listopad, A. A. Mishagin, V. V.; Shulzhenko, G. I.; Putvinsky, S. V.; Smirnov, A.

    2014-02-15

    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.

  6. Advanced Integration in Multi-Scale Mechanics and Welding Process Simulation in Weld Integrity Assessment

    SciTech Connect (OSTI)

    Vitek, J.M.; Wilkowski, G.M.; Brust, F.W.; Babu, S.

    2008-01-30

    In this project, mathematical models that predict the microstructure in pipeline steel welds were to be developed. These models were to be integrated with thermal models that describe the time-temperature history in the weld as a function of location in order to derive the spatial variation of microstructure in the weld. The microstructure predictions were also to be combined with microstructure-hardness relations, based on the additivity principle, to determine the spatial variation of hardness in the weld. EMC2 also developed microstructural models based on empirical relationships. ORNL was to pursue the development of more fundamental, theoretically based models. ORNL applied a previously developed model for inclusion formation to predict the extent and nature of inclusions that form during weld cooling from the liquid. This inclusion model was directly integrated with computational thermodynamics capability. A convenient user interface was developed for both the inclusion model and the thermodynamic phase-stability calculations. The microstructure model was based on the simultaneous transformation theory analysis as applied to the transformation of austenite to various ferrite constituents during weld cooling. The model available on the Materials Algorithm Project web site was used. Extensive modification of this model was required to correct problems with compilation and calculations as a function of the computational platform (Unix, Linux, Windows, etc.) that was used. The user interface for the inclusion model and thermodynamic phase-stability calculations was delivered to EMC2 along with the modified and correct microstructure model. Evaluation of the theoretically based model will be carried out and the predictions will be compared with experimental results as well as predictions based on the empirical models developed by EMC2.

  7. Entropy in an Arc Plasma Source

    SciTech Connect (OSTI)

    Kaminska, A.; Dudeck, M

    2008-03-19

    The entropy properties in a D.C. argon arc plasma source are studied. The local thermodynamical entropy relations are established for a set of uniform sub-systems (Ar, Ar{sup +}, e) in order to deduce the entropy balance equation in presence of dissipative effects and in the case of a thermal non equilibrium. Phenomenological linear laws are deduced in near equilibrium situation. The flow parameters inside the plasma source are calculated by a Navier-Stokes fluid description taking into account a thermal local non equilibrium. The entropy function is calculated in the plasma source using the values of the local variables obtained from the numerical code.

  8. ScanArc ASA | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg,EnergyEastCarbonOpen EnergyPonsa,Sasol ChevronSavannahScanArc

  9. AdaptiveARC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowaWisconsin: Energy Resources Jump to: navigation,Pennsylvania:AdaptiveARC

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

    SciTech Connect (OSTI)

    Oland, C.B.; Naus, D.J.

    1998-05-01

    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.

  11. Measurements of the Ion Species of Cathodic Arc Plasma in an Axial Magnetic Field

    E-Print Network [OSTI]

    Oks, Efim

    2011-01-01

    distributions of a vacuum arc plasma," Rev. Sci. Instrum. ,by filtered cathodic arc plasma," physica status solidi (a),in high current vacuum arc plasma in a magnetic field," IEEE

  12. A Summary of Recent Experimental Research on Ion Energy and Charge States of Pulsed Vacuum Arcs

    E-Print Network [OSTI]

    Oks, Efim M.

    2008-01-01

    Ion velocities in vacuum arc plasmas, J. Appl. Phys. , 2000,Anders, Cathodic Vacuum Arc Plasma of Thallium, IEEE Trans.in ca- thodic vacuum arc plasmas, J. Appl. Phys, 2007, vol.

  13. Ultrathin ta-C films on heads depositied by twist-filtered cathodic arc carbon plasmas

    E-Print Network [OSTI]

    Anders, Andre; Ryan, Francis W.

    2000-01-01

    Ion velocities in vacuum arc plasmas. submitted to J. Appl.to rid cathodic arc plasma of macro- and nanoparticles: aBrown, Transport of vacuum arc plasma through straight and

  14. Approaches to rid cathodic arc plasmas of macro- and nanoparticles: A review

    E-Print Network [OSTI]

    Anders, Andre

    2008-01-01

    Sablev, and R. I. Stupka, Plasma arc apparatus for applyingMagnetically filtered cathodic arc plasma apparatus, PatentRectangular vacuum-arc plasma source, Patent 5,480,527, Jan.

  15. Temporal Development of Ion Beam Mean Charge State in Pulsed Vacuum Arc Ion Sources

    E-Print Network [OSTI]

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

    2008-01-01

    temperature in the vacuum arc plasma and thus higher ioncharged ions in the vacuum arc plasma. The physical aspectsion charge states in vacuum arc plasma were subject of our

  16. Ion Species and Charge States of Vacuum Arc Plasma with Gas Feed and Longitudinal Magnetic Field

    E-Print Network [OSTI]

    Oks, Efim

    2010-01-01

    in cathodic vacuum arc plasmas,” J. Appl. Phys. , vol. 102,models of the cathodic arc plasma and its interaction withand Charge States of Vacuum Arc Plasma with Gas Feed and

  17. Investigation of non-hydrogenated DLC:Si prepared by cathodic arc

    E-Print Network [OSTI]

    Monteiro, Othon R.; Delplancke-Ogletree, Marie-Paule

    2002-01-01

    source filtered cathodic arc plasma, and the mechanical andpulse. Typical arc current in the plasma sources were 250 Athe cathodic arc source is 1.4 (the plasma stream consists

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

    SciTech Connect (OSTI)

    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)

    2012-09-15

    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.

  19. ARC Centre of Excellence for Advanced Silicon Photovoltaics

    E-Print Network [OSTI]

    New South Wales, University of

    ARC Centre of Excellence for Advanced Silicon Photovoltaics and Photonics Annual Report 2005 ARC Centre of Excellence for Advanced Silicon Photovoltaics and Photonics Annual Report 2005 #12;Centre of Excellence for Advanced Silicon Photovoltaics and Photonics is a Centre of Excellence of The Australian

  20. Mechanism of carbon nanostructure synthesis in arc plasma

    SciTech Connect (OSTI)

    Keidar, M.; Shashurin, A.; Volotskova, O.; Raitses, Y.; Beilis, I. I.

    2010-05-15

    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.

  1. Research Article A Customization of the Arc Marine Data

    E-Print Network [OSTI]

    Wright, Dawn Jeannine

    Research Article A Customization of the Arc Marine Data Model to Support Whale Tracking via Mate Marine Mammal Institute, Oregon State University Dawn J Wright Department of Geosciences Oregon State University Tomas Follett Marine Mammal Institute, Oregon State University Abstract The Arc Marine

  2. Toxic material measurement, monitoring, and control in the metal joining and finishing industries. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The bibliography contains citations concerning the measurement, monitoring, and control of toxic exposure to hazardous substances by workers in the metal joining and finishing industries. Topics include measurement methods and monitoring studies of workplace solvents and electroplating baths used in degreasing and painting metal surfaces. Coverage includes accepted exposure control procedures that meet health guidelines and regulations. Welding safety and health guidelines from several sources are detailed, including air contamination and welding fumes standards. References to recovery and recycling of waste metals are covered in a separate bibliography. (Contains a minimum of 122 citations and includes a subject term index and title list.)

  3. Applicability of moire deflection tomography for diagnosing arc plasmas

    SciTech Connect (OSTI)

    Chen Yunyun; Song Yang; He Anzhi; Li Zhenhua

    2009-01-20

    The argon arc plasma whose central temperature, 1.90x10{sup 4} K, is used as a practical example for an experiment to research the applicability of moire deflection tomography in arc plasma flow-field diagnosis. The experimental result indicates that moire deflection of the measured argon arc plasma is very small, even smaller than that of a common flame with the maximal temperature of nearly 1.80x10{sup 3} K. The refractive-index gradient in moire deflection tomography mainly contributes to the temperature gradient in essence when the probe wavelength and pressure are certain in plasma diagnosis. The applicable temperature ranges of moire deflection tomography in the argon arc plasma diagnosis are given with the probe wavelength 532 nm at 1 atm in certain measuring error requirements. In a word, the applicable temperature range of moire deflection tomography for arc plasma diagnosis is intimately related to the probe wavelength and the practical measuring requirements.

  4. Probing instabilities in arc plasma devices using binary gas mixtures

    SciTech Connect (OSTI)

    Ghorui, S.; Vysohlid, M.; Heberlein, J. V. R.; Pfender, E.

    2007-07-15

    This paper presents an experimental approach to identify the sources of instabilities in arc plasma devices. The phenomena of demixing in arcs have been utilized to explore the characteristics of different instabilities. Problems in explaining the observed behavior with our current understanding of the phenomena are discussed. Hydrogen is used as a secondary gas with argon as the primary plasma gas for this study. Results indicate that the observed behavior such as steady, takeover, and restrike modes of instabilities in arcs may essentially originate from the thin boundary layer over the anode wall primarily at the location of the anodic arc root. The bulk core flow apparently does not play any significant role in such instabilities. Arc currents rather than flow rates control the behavior of the instabilities in frequency space. Bifurcation of the system behavior and evidence for the existence of quadratic zones in flow space of binary gas mixtures separating steady and unsteady behavior are discussed.

  5. Measurement of total ion current from vacuum arc plasma sources

    SciTech Connect (OSTI)

    Oks, E.M.; Savkin, K.P.; Yushkov, G.Yu.; Nikolaev, A.G.; Anders, A.; Brown, I.G.

    2006-03-15

    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%. A range of different cathode materials was investigated, and the arc current was varied over the range of 50-500 A. We find that the normalized ion current (I{sub ion}/I{sub arc}) depends on the cathode material, with values in the range from 5% to 19% 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.

  6. Weld Tests Conducted by the Idaho National Laboratory

    SciTech Connect (OSTI)

    Larry Zirker; Lance Lauerhass; James Dowalo

    2007-02-01

    During the fiscal year of 2006, the Idaho National Laboratory (INL) performed many tests and work relating to the Mobile Melt-Dilute (MMD) Project components. Tests performed on the Staubli quick disconnect fittings showed promising results, but more tests were needed validate the fittings. Changes were made to the shield plug design—reduced the closure groove weld depth between the top of the canister and the top plate of the shielding plug from 0.5-in to 0.375-in deep. Other changes include a cap to cover the fitting, lifting pintle and welding code citations on the prints. Tests conducted showed stainless steel tubing, with 0.25-in, 0.375-in, and 0.5-in diameters, all with 0.035-in wall thickness, could be pinch seal welded using commercially available resistance welding equipment. Subsequent testing showed that these welds could be real-time inspected with ultrasonic inspection methods.

  7. Virtual Welded-Joint Design Integrating Advanced Materials and Processing Technologies

    SciTech Connect (OSTI)

    Yang, Z.; Dong, P.; Liu, S.; Babu, S.; Olson, G.; DebRoy, T.

    2005-04-15

    The primary goal of this project is to increase the fatigue life of a welded-joint by 10 times and to reduce energy use by 25% through product performance and productivity improvements using an integrated modeling approach. The fatigue strength of a welded-joint is currently the bottleneck to design high performance and lightweight welded structures using advanced materials such as high strength steels. In order to achieve high fatigue strength in a welded-joint it is necessary to manage the weld bead shape for lower stress concentration, produce preferable residual stress distribution, and obtain the desired microstructure for improved material toughness and strength. This is a systems challenge that requires the optimization of the welding process, the welding consumable, the base material, as well as the structure design. The concept of virtual welded-joint design has been proposed and established in this project. The goal of virtual welded-joint design is to develop a thorough procedure to predict the relationship of welding process, microstructure, property, residual stress, and the ultimate weld fatigue strength by a systematic modeling approach. The systematic approach combines five sub-models: weld thermal-fluid model, weld microstructure model, weld material property model, weld residual stress model, and weld fatigue model. The systematic approach is thus based on interdisciplinary applied sciences including heat transfer, computational fluid dynamics, materials science, engineering mechanics, and material fracture mechanics. The sub-models are based on existing models with further development. The results from modeling have been validated with critical experiments. The systematic modeling approach has been used to design high fatigue resistant welds considering the combined effects of weld bead geometry, residual stress, microstructure, and material property. In particular, a special welding wire has been developed in this project to introduce compressive residual stress at weld toe for weld fatigue resistance.

  8. 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)

    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)

    2011-01-17

    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.

  9. An Archean Oceanic Felsic Dyke Swarm In A Nascent Arc- The Hunter...

    Open Energy Info (EERE)

    indicate splitting of the arc. HMG and associated parts of the Abitibi greenstone belts bear a strong resemblance to modern rifted intraoceanic arcs of the western Pacific....

  10. Effect of underlayer on coalescence of silver islands grown by filtered cathodic arc deposition

    E-Print Network [OSTI]

    Byon, Eungsun; Anders, Andre

    2003-01-01

    1. A miniature pulsed cathodic arc plasma source 14) with ausing a pulsed cathodic arc plasma source with a Nb cathode.

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

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

    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...

  12. Planning to Gather Information Chung T. Kwok and Daniel S. Weld

    E-Print Network [OSTI]

    Planning to Gather Information Chung T. Kwok and Daniel S. Weld ctkwok, weld, relevant information sources to satisfy a user's information request (Etzioni & Weld 1994; Knoblock 1995 the relevant sources (Etzioni & Weld 1994). These motivations inspire the Occam1 planning sys- 1 William

  13. Crowdsourcing Multi-Label Classification Jonathan Bragg Mausam Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Crowdsourcing Multi-Label Classification Jonathan Bragg Mausam Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195 {jbragg, mausam, weld summarizes (Bragg, Mausam, and Weld 2013), to appear at HCOMP 2013. References Bragg, J.; Mausam; and Weld, D

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

    E-Print Network [OSTI]

    Colton, Jonathan S.

    F i W ldi PFusion Welding - Processes ver. 1 ME 6222: Manufacturing Processes and Systems Prof. J.S. Colton © GIT 2009 1 #12;Fusion weldingFusion welding · Intimate interfacial contact by using a liquid of substantiallyg q y similar composition to the base materials. · Heat + filler material = weld· Heat + filler

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

    E-Print Network [OSTI]

    Colton, Jonathan S.

    F i W ldiFusion Welding ver. 1 ME 4210: Manufacturing Processes and Engineering Prof. J.S. Colton © GIT 2009 1 #12;Fusion weldingFusion welding · Intimate interfacial contact by using a liquid of substantiallyg q y similar composition to the base materials. · Heat + filler material = weld· Heat + filler

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

    E-Print Network [OSTI]

    Grujicic, Mica

    Modifications in the AA5083 Johnson-Cook Material Model for Use in Friction Stir Welding, material microstructure and properties in friction stir welding welds of AA5083 (a non welding, Johnson-Cook material model 1. Introduction In this study, an attempt is made to modify

  17. TRANSMISSION WELDING OF GLASSES BY FEMTOSECOND LASER: STRUCTURAL AND MECHANICAL PROPERTIES

    E-Print Network [OSTI]

    Yao, Y. Lawrence

    TRANSMISSION WELDING OF GLASSES BY FEMTOSECOND LASER: STRUCTURAL AND MECHANICAL PROPERTIES Paper M processing parameters enables transmission welding. The morphology of the weld cross section was studied of the weld seams were studied through spatially resolved nanoindentation, and indentation fracture analysis

  18. The application of nanosecond-pulsed laser welding technology in MEMS packaging with a shadow mask$

    E-Print Network [OSTI]

    Lin, Liwei

    The application of nanosecond-pulsed laser welding technology in MEMS packaging with a shadow mask wiring is not pre- ferred. A comprehensive review on laser welding was given in [6]. The laser welding of laser welding is to create the liquid pool by absorption of incident radiation, allow it to grow

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

    E-Print Network [OSTI]

    Carmignani, B

    2005-01-01

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

  20. On the mechanism of operation of a cathode spot cell in a vacuum arc

    SciTech Connect (OSTI)

    Mesyats, G. A.; Petrov, A. A.; Bochkarev, M. B.; Barengolts, S. A.

    2014-05-05

    The erosive structures formed on a tungsten cathode as a result of the motion of the cathode spot of a vacuum arc over the cathode surface have been examined. It has been found that the average mass of a cathode microprotrusion having the shape of a solidified jet is approximately equal to the mass of ions removed from the cathode within the lifetime of a cathode spot cell carrying a current of several amperes. The time of formation of a new liquid-metal jet under the action of the reactive force of the plasma ejected by the cathode spot is about 10?ns, which is comparable to the lifetime of a cell. The growth rate of a liquid-metal jet is ?10{sup 4}?cm/s. The geometric shape and size of a solidified jet are such that a new explosive emission center (spot cell) can be initiated within several nanoseconds during the interaction of the jet with the dense cathode plasma. This is the underlying mechanism of the self-sustained operation of a vacuum arc.

  1. Synthesis and characterization of carbon-encapsulated magnetic nanoparticles via arc-plasma assisted CVD

    SciTech Connect (OSTI)

    Li, Z.T.; Hu, C.; Yu, C.; Qiu, J.S.

    2009-12-15

    Carbon-encapsulated magnetic nanoparticles (CEMNs) were fabricated on a large scale by arc-plasma assisted CVD in acetylene. The coal-derived metal-containing (Fe, Co and Ni) carbon rods were used as anodes, while a high-purity graphite rod was used as a cathode that remained unchanged during the arcing process. The CEMNs obtained were characterized by TEM, XRD, Raman spectroscopy, N{sub 2} adsorption isotherms and VSM. The diameter distribution of the obtained CEMNs varies from 10 to 70 nm, of which the metal cores are proximately 5-50 nm. The core phases in Fe ) nanoparticles are body-centered cubic Fe and orthorhombic Fe3C while Co ) nanoparticles and Ni ) nanoparticles show the characteristic of a face-centered cubic structure. The Fe ), Co ) and Ni ) nanoparticles with well-ordered graphitic shells have the surface area of 89 m{sup 2}/g, 72 m{sup 2}/g and 75 m{sup 2}/g, respectively. The CEMNs show ferromagnetic of which was characterized by a ratio of remnant magnetization (MR) to saturation magnetization (MS).

  2. GIS Fundamentals Lesson 8: Buffering and Overlay Lesson 8: Buffering and Overlay in ArcGIS -ArcMAP

    E-Print Network [OSTI]

    Butler, Christopher J.

    GIS Fundamentals Lesson 8: Buffering and Overlay Lesson 8: Buffering and Overlay in ArcGIS - Arc. You should read chapter 9 in the GIS Fundamentals textbook. Data: All data are in \\L9 subdirectory within the bounds of an "in" polygon. 1 #12;GIS Fundamentals Lesson 8: Buffering and Overlay Surface DIST

  3. 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]

    Sanyal, Suman

    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

  4. Historical overview on Vacuum suitable Welding and fatigue resistance in Research Devices

    E-Print Network [OSTI]

    Wolf, Martin

    2015-01-01

    New inventions change the approach of vacuum suitable welding for research purpose. With orbital welding, laser welding and robot welding the possibilities increase to fabricate larger vessels more accurately. Despite this development there is still no perfect understanding on how to avoid virtual leaks and how to make such joints suitable for dynamic stress. By recalling its historical development, it is apparent how welding mistakes began occurring systematically and how to avoid them. With ASDEX-Upgrade as an example, it is shown how the attempt to conduct vacuum suitable welding has decreased the fatigue strength. ITER could repeat the mistakes of ASDEX-Upgrade even for unwanted welding (accidental fusing of joints).

  5. Crack-arrest tests on two irradiated high-copper welds. Phase 2: Results of duplex-type experiments

    SciTech Connect (OSTI)

    Iskander, S.K.; Corwin, W.R.; Nanstad, R.K. [Oak Ridge National Lab., TN (United States)

    1994-03-01

    The objective of the Heavy-Section Steel Irradiation Program Sixth Irradiation Series is to determine the effect of neutron irradiation on the shift and shape of the lower-bound curve to crack-arrest toughness data. Two submerged-arc welds with copper contents of 0.23 and 0.31 wt % were commercially fabricated in 220-mm-thick plate. Crack-arrest specimens fabricated from these welds were irradiated at a nominal temperature of 288{degrees}C to an average fluence of 1.9 {times} 10{sup 19} neutrons/cm{sup 2} (>1 MeV). This is the second report giving the results of the tests on irradiated duplex-type crack-arrest specimens. A previous report gave results of tests on irradiated weld-embrittled-type specimens. Charpy V-notch (CVN) specimens irradiated in the same capsules as the crack-arrest specimens were also tested, and a 41-J transition temperature shift was determined from these specimens. {open_quotes}Mean{close_quote} curves of the same form as the American Society of Mechanical Engineers (ASME) K{sub la} curve were fit to the data with only the {open_quotes}reference temperature{close_quotes} as a parameter. The shift between the mean curves agrees well with the 41-J transition temperature shift obtained from the CVN specimen tests. Moreover, the four data points resulting from tests on the duplex crack-arrest specimens of the present study did not make a significant change to mean curve fits to either the previously obtained data or all the data combined.

  6. Microstructure characterization of laser welded Ti-6Al-4V fusion zones

    SciTech Connect (OSTI)

    Xu, Pei-quan; Li, Leijun, E-mail: leijun.li@ualberta.ca; Zhang, Chunbo

    2014-01-15

    The as-welded microstructure of laser-welded Ti-6Al-4V is characterized as a function of CO2 key-hole mode laser welding speed. Martensitic ?? is the predominant phase, with some ? and retained ?. Phase transformation is affected by the cooling rate through laser welding speed. A higher welding speed of 1.6 to 2.0 m/min produced more martensite ?? and less retained ? in the welds. 1.4 m/min welding speed produced small amounts of ?, besides the martensite ??. A trace of ? titanium hydride phase seems to have formed in the weld fusion zone. Moiré fringes are a common feature in the TEM microstructure, due to abundance of multi-phase interfaces. Tensile twins and clusters of dislocations indicate that plastic deformation has happened in the as-welded microstructure, indicating the local stress levels to be approaching the yield stress on-cooling during laser welding.

  7. Matching univalent functions and conformal welding

    E-Print Network [OSTI]

    Grong, Erlend; Vasil'ev, Alexander

    2008-01-01

    Given a conformal mapping $f$ of the unit disk $\\mathbb D$ onto a simply connected domain $D$ in the complex plane bounded by a closed Jordan curve, we consider the problem of constructing a matching conformal mapping, i.e., the mapping of the exterior of the unit disk $\\mathbb D^*$ onto the exterior domain $D^*$ regarding to $D$. The answer is expressed in terms of a linear differential equation with a driving term given as the kernel of an operator dependent on the original mapping $f$. Examples are provided. This study is related to the problem of conformal welding and to representation of the Virasoro algebra in the space of univalent functions.

  8. Matching univalent functions and conformal welding

    E-Print Network [OSTI]

    Erlend Grong; Pavel Gumenyuk; Alexander Vasil'ev

    2008-06-05

    Given a conformal mapping $f$ of the unit disk $\\mathbb D$ onto a simply connected domain $D$ in the complex plane bounded by a closed Jordan curve, we consider the problem of constructing a matching conformal mapping, i.e., the mapping of the exterior of the unit disk $\\mathbb D^*$ onto the exterior domain $D^*$ regarding to $D$. The answer is expressed in terms of a linear differential equation with a driving term given as the kernel of an operator dependent on the original mapping $f$. Examples are provided. This study is related to the problem of conformal welding and to representation of the Virasoro algebra in the space of univalent functions.

  9. Low temperature formation of electrode having electrically conductive metal oxide surface

    DOE Patents [OSTI]

    Anders, Simone (Albany, CA); Anders, Andre (Albany, CA); Brown, Ian G. (Berkeley, CA); McLarnon, Frank R. (Orinda, CA); Kong, Fanping (Berkeley, CA)

    1998-01-01

    A low temperature process is disclosed for forming metal suboxides on substrates by cathodic arc deposition by either controlling the pressure of the oxygen present in the deposition chamber, or by controlling the density of the metal flux, or by a combination of such adjustments, to thereby control the ratio of oxide to metal in the deposited metal suboxide coating. The density of the metal flux may, in turn, be adjusted by controlling the discharge current of the arc, by adjusting the pulse length (duration of on cycle) of the arc, and by adjusting the frequency of the arc, or any combination of these parameters. In a preferred embodiment, a low temperature process is disclosed for forming an electrically conductive metal suboxide, such as, for example, an electrically conductive suboxide of titanium, on an electrode surface, such as the surface of a nickel oxide electrode, by such cathodic arc deposition and control of the deposition parameters. In the preferred embodiment, the process results in a titanium suboxide-coated nickel oxide electrode exhibiting reduced parasitic evolution of oxygen during charging of a cell made using such an electrode as the positive electrode, as well as exhibiting high oxygen overpotential, resulting in suppression of oxygen evolution at the electrode at full charge of the cell.

  10. Composite metal foil and ceramic fabric materials

    DOE Patents [OSTI]

    Webb, B.J.; Antoniak, Z.I.; Prater, J.T.; DeSteese, J.G.

    1992-03-24

    The invention comprises new materials useful in a wide variety of terrestrial and space applications. In one aspect, the invention comprises a flexible cloth-like material comprising a layer of flexible woven ceramic fabric bonded with a layer of metallic foil. In another aspect, the invention includes a flexible fluid impermeable barrier comprising a flexible woven ceramic fabric layer having metal wire woven therein. A metallic foil layer is incontinuously welded to the woven metal wire. In yet another aspect, the invention includes a material comprising a layer of flexible woven ceramic fabric bonded with a layer of an organic polymer. In still another aspect, the invention includes a rigid fabric structure comprising a flexible woven ceramic fabric and a resinous support material which has been hardened as the direct result of exposure to ultraviolet light. Inventive methods for producing such material are also disclosed. 11 figs.

  11. Metal aminoboranes

    DOE Patents [OSTI]

    Burrell, Anthony K.; Davis, Benjamin J.; Thorn, David L.; Gordon, John C.; Baker, R. Thomas; Semelsberger, Troy Allen; Tumas, William; Diyabalanage, Himashinie Vichalya Kaviraj; Shrestha, Roshan P.

    2010-05-11

    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.

  12. Lidar arc scan uncertainty reduction through scanning geometry optimization

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, H.; Barthelmie, R. J.; Pryor, S. C.; Brown, G.

    2015-10-07

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine powermore »performance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.« less

  13. mARC: Memory by Association and Reinforcement of Contexts

    E-Print Network [OSTI]

    Norbert Rimoux; Patrice Descourt

    2013-12-10

    This paper introduces the memory by Association and Reinforcement of Contexts (mARC). mARC is a novel data modeling technology rooted in the second quantization formulation of quantum mechanics. It is an all-purpose incremental and unsupervised data storage and retrieval system which can be applied to all types of signal or data, structured or unstructured, textual or not. mARC can be applied to a wide range of information clas-sification and retrieval problems like e-Discovery or contextual navigation. It can also for-mulated in the artificial life framework a.k.a Conway "Game Of Life" Theory. In contrast to Conway approach, the objects evolve in a massively multidimensional space. In order to start evaluating the potential of mARC we have built a mARC-based Internet search en-gine demonstrator with contextual functionality. We compare the behavior of the mARC demonstrator with Google search both in terms of performance and relevance. In the study we find that the mARC search engine demonstrator outperforms Google search by an order of magnitude in response time while providing more relevant results for some classes of queries.

  14. A study of the mechanism of laser welding defects in low thermal expansion superalloy GH909

    SciTech Connect (OSTI)

    Yan, Fei; Wang, Chunming, E-mail: yanxiangfei225@163.com; Wang, Yajun; Hu, Xiyuan; Wang, Tianjiao; Li, Jianmin; Li, Guozhu

    2013-04-15

    In this paper, we describe experimental laser welding of low-thermal-expansion superalloy GH909. The main welding defects of GH909 by laser in the weld are liquation cracks and porosities, including hydrogen and carbon monoxide porosity. The forming mechanism of laser welding defects was investigated. This investigation was conducted using an optical microscope, scanning electron microscope, energy diffraction spectrum, X-ray diffractometer and other methodologies. The results demonstrated that porosities appearing in the central weld were related to incomplete removal of oxide film on the surface of the welding samples. The porosities produced by these bubbles were formed as a result of residual hydrogen or oxygenium in the weld. These elements failed to escape from the weld since laser welding has both a rapid welding speed and cooling rate. The emerging crack in the heat affected zone is a liquation crack and extends along the grain boundary as a result of composition segregation. Laves–Ni{sub 2}Ti phase with low melting point is a harmful phase, and the stress causes grain boundaries to liquefy, migrate and even crack. Removing the oxides on the surface of the samples before welding and carefully controlling technological parameters can reduce welding defects and improve formation of the GH909 alloy weld. - Highlights: ? It is a new process for the forming of GH909 alloy via laser welding. ? The forming mechanism of laser welding defects in GH909 has been studied. ? It may be a means to improve the efficiency of aircraft engine production.

  15. Friction Stir Spot Welding of DP780 Carbon Steel

    SciTech Connect (OSTI)

    Santella, Michael L [ORNL; Hovanski, Yuri [ORNL; Frederick, David Alan [ORNL; Grant, Glenn J [ORNL; Dahl, Michael E [ORNL

    2010-01-01

    Friction stir spot welds were made in uncoated and galvannealed DP780 sheets using polycrystalline boron nitride stir tools. The tools were plunged at either a single continuous rate or in two segments consisting of a relatively high rate followed by a slower rate of shorter depth. Welding times ranged from 1 to 10 s. Increasing tool rotation speed from 800 to 1600 rev min{sup -1} increased strength values. The 2-segment welding procedures also produced higher strength joints. Average lap shear strengths exceeding 10 {center_dot} 3 kN were consistently obtained in 4 s on both the uncoated and the galvannealed DP780. The likelihood of diffusion and mechanical interlocking contributing to bond formation was supported by metallographic examinations. A cost analysis based on spot welding in automobile assembly showed that for friction stir spot welding to be economically competitive with resistance spot welding the cost of stir tools must approach that of resistance spot welding electrode tips.

  16. Gaseous and particulate emissions from a DC arc melter

    SciTech Connect (OSTI)

    Overcamp, T.J.; Speer, M.P.; Griner, S.J.; Cash, D.M. [Clemson Univ., Anderson, SC (United States)

    1997-12-31

    This paper presents the results of the gaseous and particulate emissions from eight experimental tests of a DC arc melter to treat simulated Savannah River soils contaminated with metals, surrogates for radionuclides, and organic debris. The gaseous analyses reported on the concentrations of oxygen, hydrogen, carbon monoxide, carbon dioxide, hydrogen, methane, nitric oxide, and nitrogen dioxide. The carbon dioxide concentration was high for all runs. For the runs with an air purge, the carbon monoxide concentration ranged up to 10% in the runs with the debris and 2% in the runs without debris. Hydrogen ranged up to 5% by with debris and up to 1% without debris. The methane concentration ranged up to 7,000 ppm{sub v} for the runs with debris and 2,000 ppm for the runs without debris. With a nitrogen purge, oxygen concentrations were less than 1%. The carbon dioxide concentrations ranged from 3 to 15%. Much of this carbon dioxide was probably due the carbonates added to the feed material. The carbon monoxide concentration ranged up to 20% with the debris and 7% without debris. Hydrogen was above 6% in with debris and up to 6% without debris. The methane concentration ranged up to 10,000 ppm{sub v} with debris and 4,000 ppm{sub v} without debris. The particulate concentrations exiting ranged from 32 to 145 g/m{sup 3}. From the chemical analyses, the primary elements were silicon and calcium. The CHN analyses indicated that carbon, probably as carbonates, are an additional component in the particulate matter. The estimated emissions were at a level of 3% or less for cerium, up to 7% for nickel, and 11 to 30% for cesium.

  17. Apparatus for coating a surface with a metal utilizing a plasma source

    DOE Patents [OSTI]

    Brown, I.G.; MacGill, R.A.; Galvin, J.E.

    1991-05-07

    An apparatus and method are disclosed for coating or layering a surface with a metal utilizing a metal vapor vacuum arc plasma source. The apparatus includes a trigger mechanism for actuating the metal vacuum vapor arc plasma source in a pulsed mode at a predetermined rate. The surface or substrate to be coated or layered is supported in position with the plasma source in a vacuum chamber. The surface is electrically biased for a selected period of time during the pulsed mode of operation of the plasma source. Both the pulsing of the metal vapor vacuum arc plasma source and the electrical biasing of the surface are synchronized for selected periods of time. 10 figures.

  18. Hot Pin Welding of Thin Poly(vinyl chloride) Sheet James D. Van de Ven, Arthur G. Erdman

    E-Print Network [OSTI]

    Van de Ven, James D.

    Hot Pin Welding of Thin Poly(vinyl chloride) Sheet James D. Van de Ven, Arthur G. Erdman Mechanical of welding two thin sheets of poly(vinyl chloride) (PVC) with a heated pin, thus allowing construction of a relationship between the weld temperature and weld strength. Constructing a relationship between weld strength

  19. Acoustic stabilization of electric arc instabilities in nontransferred plasma torches

    SciTech Connect (OSTI)

    Rat, V.; Coudert, J. F.

    2010-03-08

    Electric arc instabilities in dc plasma torches lead to nonhomogeneous treatments of nanosized solid particles or liquids injected within thermal plasma jets. This paper shows that an additional acoustic resonator mounted on the cathode cavity allows reaching a significant damping of these instabilities, particularly the Helmholtz mode of arc oscillations. The acoustic resonator is coupled with the Helmholtz resonator of the plasma torch limiting the amplitude of arc voltage variations. It is also highlighted that this damping is dependent on friction effects in the acoustic resonator.

  20. Numerical simulation of carbon arc discharge for nanoparticle synthesis

    SciTech Connect (OSTI)

    Kundrapu, M.; Keidar, M.

    2012-07-15

    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.