National Library of Energy BETA

Sample records for welding stress management

  1. 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

  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. 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...

  4. Thermoacoustic method for relaxation of residual stresses in welded joints

    SciTech Connect (OSTI)

    Koshovyi, V.V.; Pakhn`o, M.I.; Tsykhan, O.I.

    1995-01-01

    We propose a thermoacoustic method for the relaxation of residual stresses in welded joints, present a block diagram of a generator of local thermoacoustic pulses designed for implementation of this method, and describe our experiment aimed at relaxation of residual tensile stresses.

  5. Ultrasonic measurement of residual stress relaxation in welded steel plates using critically refracted longitudinal waves 

    E-Print Network [OSTI]

    Chance, Brent Houston

    2000-01-01

    This study investigates whether or not there is a measurable amount of residual transverse stress relaxation in welded steel. This was determined by using two different methods of stress measurement. These methods involved ...

  6. Ultrasonic inspection of austenitic stainless steel welds with artificially produced stress corrosion cracks

    SciTech Connect (OSTI)

    Dugan, Sandra; Wagner, Sabine [Materials Testing Institute University of Stuttgart (MPA), Pfaffenwaldring 32, 70569 Stuttgart (Germany)

    2014-02-18

    Austenitic stainless steel welds and nickel alloy welds, which are widely used in nuclear power plants, present major challenges for ultrasonic inspection due to the grain structure in the weld. Large grains in combination with the elastic anisotropy of the material lead to increased scattering and affect sound wave propagation in the weld. This results in a reduced signal-to-noise ratio, and complicates the interpretation of signals and the localization of defects. Mechanized ultrasonic inspection was applied to study austenitic stainless steel test blocks with different types of flaws, including inter-granular stress corrosion cracks (IGSCC). The results show that cracks located in the heat affected zone of the weld are easily detected when inspection from both sides of the weld is possible. In cases of limited accessibility, when ultrasonic inspection can be carried out only from one side of a weld, it may be difficult to distinguish between signals from scattering in the weld and signals from cracks.

  7. Neutron diffraction measurements of residual stresses in friction stir welding: a review

    SciTech Connect (OSTI)

    Woo, Wan Chuck [ORNL; Feng, Zhili [ORNL; Wang, Xun-Li [ORNL; David, Stan A [ORNL

    2011-01-01

    Significant amounts of residual stresses are often generated during welding and result in critical degradation of the structural integrity and performance of components. Neutron diffraction has become a well established technique for the determination of residual stresses in welds because of the unique deep penetration, three-dimensional mapping capability, and volume averaged bulk measurements characteristic of the scattering neutron beam. Friction stir welding has gained prominence in recent years. The authors reviewed a number of neutron diffraction measurements of residual stresses in friction stir welds and highlighted examples addressing how the microstructures and residual stresses are correlated with each other. An example of in situ neutron diffraction measurement result shows the evolution of the residual stresses during welding.

  8. 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 ...

  9. Characterization of residual stress relaxation in welded steel plate using TAP-NDE and wavelets 

    E-Print Network [OSTI]

    Jhun, Choon-Sik

    2001-01-01

    This thesis presents the characterization of residual stress relaxation in a welded ASTM 1018 steel plate by using the Thermo-Acousto-Photonic Nondestructive Evaluation (TAP-NDE) technique and the Gabor Wavelet Transform (GWT) which together produce...

  10. The Effect of Weld Residual Stress on Life of Used Nuclear Fuel Dry Storage Canisters

    SciTech Connect (OSTI)

    Ronald G. Ballinger; Sara E. Ferry; Bradley P. Black; Sebastien P. Teysseyre

    2013-08-01

    With the elimination of Yucca Mountain as the long-term storage facility for spent nuclear fuel in the United States, a number of other storage options are being explored. Currently, used fuel is stored in dry-storage cask systems constructed of steel and concrete. It is likely that used fuel will continue to be stored at existing open-air storage sites for up to 100 years. This raises the possibility that the storage casks will be exposed to a salt-containing environment for the duration of their time in interim storage. Austenitic stainless steels, which are used to construct the canisters, are susceptible to stress corrosion cracking (SCC) in chloride-containing environments if a continuous aqueous film can be maintained on the surface and the material is under stress. Because steel sensitization in the canister welds is typically avoided by avoiding post-weld heat treatments, high residual stresses are present in the welds. While the environment history will play a key role in establishing the chemical conditions for cracking, weld residual stresses will have a strong influence on both crack initiation and propagation. It is often assumed for modeling purposes that weld residual stresses are tensile, high and constant through the weld. However, due to the strong dependence of crack growth rate on stress, this assumption may be overly conservative. In particular, the residual stresses become negative (compressive) at certain points in the weld. The ultimate goal of this research project is to develop a probabilistic model with quantified uncertainties for SCC failure in the dry storage casks. In this paper, the results of a study of the residual stresses, and their postulated effects on SCC behavior, in actual canister welds are presented. Progress on the development of the model is reported.

  11. Microstructural Design for Stress Wave Energy Management /

    E-Print Network [OSTI]

    Tehranian, Aref

    2013-01-01

    Nasser, S. , 2010. Stress-wave energy management throughNemat-Nasser, Stress-wave energy management through materialconstitute pressure wave energy and/or shear wave energy.

  12. Microstructural Design for Stress Wave Energy Management /

    E-Print Network [OSTI]

    Tehranian, Aref

    2013-01-01

    Nasser, S. , 2010. Stress-wave energy management throughNemat-Nasser, Stress-wave energy management through materialS. , 2009. Acoustic wave-energy management in composite

  13. Managing Academic Stress Are You Experience Too Much Stress?

    E-Print Network [OSTI]

    Kunkle, Tom

    Managing Academic Stress Are You Experience Too Much Stress? Sources of Academic Stress Course for yourself Ways to Reduce Academic Stress Take a look at your course load. For every hour you are in class are not doing it effectively then you may be causing yourself more stress. Find out what your learning

  14. 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

  15. 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

  16. Singapore Welding Society Newsletter, Sepember 1998 Stress Corrosion Cracking

    E-Print Network [OSTI]

    Zhou, Wei

    certainly plays a role in the SCC process, but it should be pointed out that not all types of stresses measures. Good knowledge of SCC may help petrochemical industry save lots of money. There is a tendency

  17. Stress Management Stress is part of everyday life. Examples of stressful situations for university students

    E-Print Network [OSTI]

    Wapstra, Erik

    Stress Management Stress is part of everyday life. Examples of stressful situations for university stress can actually be beneficial as a motivator, higher levels of ongoing stress can lead to medical, psychological and social problems. WHAT IS STRESS? Stress refers to the demands, pressures or forces applied

  18. An investigation of stress concentration effects in welding elbows 

    E-Print Network [OSTI]

    Ballard, Mike Wayne

    1987-01-01

    FIGURE 8. STRESS CONCENTRATION FACTOR (K?) 30 150 150 V%DISS DATk d merc eggnn aagg 90 50 -10 -5 0 5 10 FIGURE 9' STRESS CONCENTRATION FACTOR ~KT) 31 The ASME code gives values for the parameters, a and m of 0. 9 and 2/3 respectively.... , "Properties of Thin Walled Curved Tubes of Short-Bend Radius, " Tran. ASME, Vol. 73, No. l, 1951, pp. 78-82. 34 Shigley, J. E. , and Mitchell, L. D. , Mechanical En ineerin Desi n, McGraw-Hill, New York, 1983, pp. 79 ? 85. 40 APPENDIX I The subroutine...

  19. Characterization of Residual Stress as a Function of Friction Stir Welding Parameters in Oxide Dispersion Strengthened (ODS) Steel MA956

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

    Brewer, Luke N.; Bennett, Martin S.; Baker, B. W.; Payzant, E. Andrew; Kolbus, Lindsay M.

    2015-09-08

    This article characterizes the residual stresses generated by friction stir welding of oxide dispersion strengthened steel MA956 over a series of welding conditions. A plate of MA956 steel was friction stir welded at three conditions: 500 rpm/25 millimeters per minute (mmpm), 400 rpm/50 mmpm and 400 rpm/100 mmpm. The residual stresses across these welds were measured using both x-ray and neutron diffraction techniques. Longitudinal residual stresses up to eighty percent of the yield strength were observed for the 400 rpm/100 mmpm condition. Increasing the traverse rate while holding the rotational speed fixed increased the residual stress levels in the stirmore »zone and at the stir zone-thermomechanically affected zone interface. The stress profiles displayed the characteristic M shape, and the asymmetry between advancing and retreating stress peaks was limited, occurring mainly on the root side of the weld. The large magnitude of the stresses was maintained throughout the thickness of the plates.« less

  20. 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.

  1. 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.

  2. STRESS MANAGEMENT Stress occurs in everyone's life. How stressful something is depends on how we perceive it. Stress is not

    E-Print Network [OSTI]

    Wu, Shin-Tson

    STRESS MANAGEMENT Stress occurs in everyone's life. How stressful something is depends on how we perceive it. Stress is not necessarily a bad thing. It can help to motivate and drive us toward our goals levels of stress can have a negative impact. Medical school is demanding and can cause both prolonged

  3. Status report. Characterization of Weld Residual Stresses on a Full-Diameter SNF Interim Storage Canister Mockup.

    SciTech Connect (OSTI)

    Enos, David; Bryan, Charles R.

    2015-08-01

    This report documents the mockup specifications and manufacturing processes; the initial cutting of the mockup into three cylindrical pieces for testing and the measured strain changes that occurred during the cutting process; and the planned weld residual stress characterization activities and the status of those activities.

  4. Microstructural Design for Stress Wave Energy Management /

    E-Print Network [OSTI]

    Tehranian, Aref

    2013-01-01

    mode of pressure wave and energy transfer into shearmode of pressure wave and energy transfer into shear mode ItNasser, S. , 2010. Stress-wave energy management through

  5. Critical Incident Stress Management (CISM): Group Crisis Intervention, 4th June 2006, International Critical Incident Stress Foundation, Inc.

    E-Print Network [OSTI]

    Oliver, Douglas L.

    Critical Incident Stress Management (CISM): Group Crisis Intervention, 4th Edition, June 2006 Management (CISM): Group Crisis Intervention, 4th Edition, June 2006, International Critical Incident Stress

  6. Ultrasonic measurement of the residual stresses in patch welded steel plates 

    E-Print Network [OSTI]

    Junghans, Paul Gerard

    1994-01-01

    This study begins with a review of the nature and origins of residual stresses and the techniques currently used to measure these stresses, both destructive and nondestructive. The theory of ultrasonic stress measurement, ...

  7. Assessment of Weld Overlays for Mitigating Primary Water Stress Corrosion Cracking at Nickel Alloy Butt Welds in Piping Systems Approved for Leak-Before-Break

    SciTech Connect (OSTI)

    Sullivan, Edward J.; Anderson, Michael T.

    2012-08-01

    This TLR provides an assessment of weld overlays as a mitigation strategy for PWSCC, and includes an assessment of the WOL-related inspection requirements of Code Case N-770-1, as conditioned in §50.55a.

  8. Groundwater under stress: the importance of management

    E-Print Network [OSTI]

    Vaux, Henry

    2011-01-01

    static or decline. Groundwater will be uniquely attractiveThe need to manage groundwater ef?ciently and effectively asthe aquifer. Most methods of groundwater management involve

  9. Full-Scale Tests of Butt-Welded Splices in Heavy-Rolled Steel Sections Subjected to Primary Tensile Stresses

    E-Print Network [OSTI]

    Bruneau, Michel

    of the observed failure. The splice with full penetration welds exhibited satisfactory strength and ductility are to be performed. Several cases of partial or complete brittle fracture have been reported during fabrication toughness of the base material at the failed joint. The weld design and process used resulted in an initial

  10. 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.

  11. Assessment of the Mechanical Stress Improvement Process for Mitigating Primary Water Stress Corrosion Cracking in Nickel Alloy Butt Welds in Piping Systems Approved for Leak-Before-Break

    SciTech Connect (OSTI)

    Sullivan, Edmund J.; Anderson, Michael T.

    2013-01-01

    This report provides an assessment of the use of Mechanical Stress Improvement Process to reduce, or decrease, stress-driven degradation, i.e., primary water stress corrosion cracking.

  12. Stress in Adults after a Disaster: Warning Signs and Management 

    E-Print Network [OSTI]

    Warren, Judith L.

    2005-09-30

    performance. Stress in Adults after a Disaster: Warning Signs and Management Avoidance ? Adults may want to avoid places or things that remind them of the event. Such remind- ers bring back the strong emotions they experienced during the disaster... thoughts of the disaster and worry about the future. Impaired work performance ? It is common for work performance and productivity to drop after a disaster. Occupational achievement may seem less important after a tragedy. Relationships and work...

  13. 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

  14. 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

  15. 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

  16. 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...

  17. Welding Procedures and Type IV Phenomena J.A. Francis, W. Mazur

    E-Print Network [OSTI]

    Cambridge, University of

    Welding Procedures and Type IV Phenomena J.A. Francis, W. Mazur CSIRO Manufacturing of the type IV rupture stress for welds in ferritic power plant steels containing 9­12 wt. % chromium, using, to infer the dependence of the stress on welding parameters. The rupture stress increases with the preheat

  18. 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

  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. 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...

  1. 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.

  2. 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.

  3. 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

  4. 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

  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 -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

  7. 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

  8. 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.

  9. 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.

  10. Stress Management as an Enabling Technology for High-Field Superconducting Dipole Magnets 

    E-Print Network [OSTI]

    Holik, Eddie Frank

    2014-06-03

    This dissertation examines stress management and other construction techniques as means to meet future accelerator requirement demands by planning, fabricating, and analyzing a high-field, Nb_(3)Sn dipole. In order to ...

  11. How to Master Stress 1. Understanding Stress

    E-Print Network [OSTI]

    Kunkle, Tom

    1 How to Master Stress 1. Understanding Stress Introduction to Stress Management Understanding Stress o Survival Stress o Internally Generated Stress o Environmental Stress, Job Stress and Fatigue How to Recognize Stress Optimizing Your Levels of Stress Managing Life Crises How stress can get

  12. 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

  13. 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).

  14. Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia Nemat-Nasser

    E-Print Network [OSTI]

    Nemat-Nasser, Sia

    Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia that if this axis initially coincides with the stress-wave vector, then the energy of the plane waves would closely the required anisotropy, and to experimentally demonstrate the management of stress-wave energy in a desired

  15. 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.

  16. Comparison of alloying concepts for Low Transformation Temperature (LTT) welding consumables

    E-Print Network [OSTI]

    Cambridge, University of

    Comparison of alloying concepts for Low Transformation Temperature (LTT) welding consumables L. Karlsson1 , L. Mráz2 , H. K. D. H. Bhadeshia3 and A. A. Shirzadi4 1 ESAB AB, Göteborg, Sweden 2 Welding Abstract Fatigue cracks often initiate at welds as a consequence of large residual stresses and changes

  17. Characterization of Confined Pinch Welds in Type 304L Stainless Steel

    SciTech Connect (OSTI)

    Korinko, P.S.

    2002-02-28

    This paper describes efforts that were undertaken to characterize the stresses induced in resistance pinch welds used to contain high pressure gasses.

  18. 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.

  19. Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia Nemat-Nasser

    E-Print Network [OSTI]

    Nemat-Nasser, Sia

    Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia February 2010 Accepted 11 March 2010 Available online 27 March 2010 Stress-wave propagation in solids can that if this axis initially coincides with the stress-wave vector, then the energy of the plane waves would closely

  20. Modulation of the Maladaptive Stress Response to Manage Diseases of Protein Folding

    E-Print Network [OSTI]

    Morimoto, Richard

    Modulation of the Maladaptive Stress Response to Manage Diseases of Protein Folding Daniela Martino homeostasis components that direct protein folding and function. To identify global principles of misfolding. In diseased cells, maladaptation alters protein structure­function relationships, impacts protein folding

  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. 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.

  3. 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.

  4. 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

  5. Abscisic Acid-Regulated Growth Modulations and Its Application for Stress and Quality Management of Vegetable Transplants 

    E-Print Network [OSTI]

    Agehara, Shinsuke

    2014-08-01

    The goal of this study is to develop a management tool for producing high quality, more stress tolerant vegetable transplants and for prolonging transplant marketability. This study primarily involves physiological and ...

  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. 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

  8. 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.

  9. 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.

  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. 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. 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.

  14. 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.

  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. 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

  17. FINITE ELEMENT ANALYSIS OF THERMAL TENSIONING TECHNIQUES MITIGATING WELD BUCKLING DISTORTION

    E-Print Network [OSTI]

    Michaleris, Panagiotis

    FINITE ELEMENT ANALYSIS OF THERMAL TENSIONING TECHNIQUES MITIGATING WELD BUCKLING DISTORTION. This paper presents a finite element analysis model of the thermal tensioning technique. A series of finite by the finite element simulations, the residual stresses of large size and high heat input welds are reduced

  18. 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.

  19. 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 ...

  20. 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.

  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. Fracture mechanics analysis on the resistance of welded details under variable amplitude long life loading 

    E-Print Network [OSTI]

    Zhou, Minjian

    1993-01-01

    Fracture mechanics approach has been used to analyze the behavior of fatigue resistance of welded details existing in highway steel bridges under variable amplitude long life loading which means most of the stress ranges will be below constant...

  5. HANFORD SITE WELDING PROGRAM SUCCESSFULLY PROVIDING A SINGLE SITE FUNCTION FOR USE BY MULTIPLE CONTRACTORS

    SciTech Connect (OSTI)

    CANNELL GR

    2009-11-19

    The Department of Energy, Richland Operations (DOE-RL) recently restructured its Hanford work scope, awarding two new contracts over the past several months for a total of three contracts to manage the sites cleanup efforts. DOE-RL met with key contractor personnel prior to and during contract transition to ensure site welding activities had appropriate oversight and maintained code compliance. The transition also provided an opportunity to establish a single site-wide function that would provide welding and materials engineering services to the Hanford site contractors: CH2M HILL Plateau Remediation Company (CHPRC); Mission Support Alliance (MSA); Washington River Protection Solutions (WRPS); and Washington Closure Hanford (WCH). Over the years, multiple and separate welding programs (amongst the several contractors) existed at the Hanford site leading to inefficiencies resulting from duplication of administrative efforts, maintenance of welding procedures, welder performance certifications, etc. The new, single program eliminates these inefficiencies. The new program, co-managed by two of the sites' new contractors, the CHPRC ('owner' of the program and responsible for construction welding services) and the MSA (provides maintenance welding services), provides more than just the traditional construction and maintenance welding services. Also provided, are welding engineering, specialty welding development/qualification for the closure of radioactive materials containers and materials evaluation/failure analysis. The following describes the new Hanford site welding program.

  6. RESIDUAL STRESSES IN 3013 CONTAINERS

    SciTech Connect (OSTI)

    Mickalonis, J.; Dunn, K.

    2009-11-10

    The DOE Complex is packaging plutonium-bearing materials for storage and eventual disposition or disposal. The materials are handled according to the DOE-STD-3013 which outlines general requirements for stabilization, packaging and long-term storage. The storage vessels for the plutonium-bearing materials are termed 3013 containers. Stress corrosion cracking has been identified as a potential container degradation mode and this work determined that the residual stresses in the containers are sufficient to support such cracking. Sections of the 3013 outer, inner, and convenience containers, in both the as-fabricated condition and the closure welded condition, were evaluated per ASTM standard G-36. The standard requires exposure to a boiling magnesium chloride solution, which is an aggressive testing solution. Tests in a less aggressive 40% calcium chloride solution were also conducted. These tests were used to reveal the relative stress corrosion cracking susceptibility of the as fabricated 3013 containers. Significant cracking was observed in all containers in areas near welds and transitions in the container diameter. Stress corrosion cracks developed in both the lid and the body of gas tungsten arc welded and laser closure welded containers. The development of stress corrosion cracks in the as-fabricated and in the closure welded container samples demonstrates that the residual stresses in the 3013 containers are sufficient to support stress corrosion cracking if the environmental conditions inside the containers do not preclude the cracking process.

  7. 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.

  8. 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)

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Construction challenges and solutions in TAMU3, a 14 T stress-managed Nb{sub 3}Sn dipole

    SciTech Connect (OSTI)

    Holik, E. F.; Garrison, R.; Diaczenko, N.; Elliott, T.; Jaisle, A.; McInturff, A. D.; McIntyre, P.; Sattarov, A.

    2014-01-29

    The Accelerator Research Laboratory at Texas A and M University is nearing completion of a Nb{sub 3}Sn dipole that incorporates stress management directly in its windings. The windings utilize graded-cross-section cable made from 54/61 (54 out of a 61 subelement hexagonal pattern) Restacked Rod Processed® Nb{sub 3}Sn/Cu conductor and fine-filament S-2 glass fabric insulation. Coil heat treatment and associated differential expansions have brought about some tin leakage, highresistance electrical shorts, and coil gaps. TAMU3b impregnation successfully increased the coil-to-ground resistance. Quench protection in TAMU3 was simulated using QUENCH. The tests of TAMU3 should provide the first examination of stress management at field intensities greater than 12 T.

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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...

  19. Manufacturing and characterization of welded, sintered condensers for a loop heat pipe

    E-Print Network [OSTI]

    Sircar, Jay D

    2013-01-01

    A manufacturing process plan was developed for a welded condenser utilizing a sintered wick. Electronic devices have progressed to the point where new designs are limited by the thermal management system used to ensure ...

  20. Job Stress in Disaster Case Managers Working with Hurricane Ike Recovery 

    E-Print Network [OSTI]

    Forman, Megan Hajecate

    2011-10-21

    Hurricane Ike struck the coast of Texas on September 13, 2008. The Federal Emergency Management Agency (FEMA), a branch of the United States Department of Homeland Security, implemented a Disaster Case Management Pilot (DCM-P) project to help...

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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:

  11. 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.

  12. Residual Stresses in Weldments by Neutron Diffraction

    E-Print Network [OSTI]

    Bandara, Arosha

    Residual Stresses in Weldments by Neutron Diffraction Shanmukha Rao M, Jon James, Shirley Northover :- The neutron diffraction is determined from Bragg's law. When neutron propagate through crystal sample, Coherent, Incoherent and Absorption Scattering phenomena take place Weld MaterialsPlate materials Stress

  13. ADVANCED INTEGRATION OF MULTI-SCALE MECHANICS AND WELDING PROCESS SIMULATION IN WELD INTEGRITY ASSESSMENT

    SciTech Connect (OSTI)

    Wilkowski, Gery M.; Rudland, David L.; Shim, Do-Jun; Brust, Frederick W.; Babu, Sundarsanam

    2008-06-30

    The potential to save trillions of BTU’s in energy usage and billions of dollars in cost on an annual basis based on use of higher strength steel in major oil and gas transmission pipeline construction is a compelling opportunity recognized by both the US Department of Energy (DOE). The use of high-strength steels (X100) is expected to result in energy savings across the spectrum, from manufacturing the pipe to transportation and fabrication, including welding of line pipe. Elementary examples of energy savings include more the 25 trillion BTUs saved annually based on lower energy costs to produce the thinner-walled high-strength steel pipe, with the potential for the US part of the Alaskan pipeline alone saving more than 7 trillion BTU in production and much more in transportation and assembling. Annual production, maintenance and installation of just US domestic transmission pipeline is likely to save 5 to 10 times this amount based on current planned and anticipated expansions of oil and gas lines in North America. Among the most important conclusions from these studies were: • While computational weld models to predict residual stress and distortions are well-established and accurate, related microstructure models need improvement. • Fracture Initiation Transition Temperature (FITT) Master Curve properly predicts surface-cracked pipe brittle-to-ductile initiation temperature. It has value in developing Codes and Standards to better correlate full-scale behavior from either CTOD or Charpy test results with the proper temperature shifts from the FITT master curve method. • For stress-based flaw evaluation criteria, the new circumferentially cracked pipe limit-load solution in the 2007 API 1104 Appendix A approach is overly conservative by a factor of 4/?, which has additional implications. . • For strain-based design of girth weld defects, the hoop stress effect is the most significant parameter impacting CTOD-driving force and can increase the crack-driving force by a factor of 2 depending on strain-hardening, pressure level as a % of SMYS, and flaw size. • From years of experience in circumferential fracture analyses and experimentation, there has not been sufficient integration of work performed for other industries into analogous problems facing the oil and gas pipeline markets. Some very basic concepts and problems solved previously in these fields could have circumvented inconsistencies seen in the stress-based and strain-based analysis efforts. For example, in nuclear utility piping work, more detailed elastic-plastic fracture analyses were always validated in their ability to predict loads and displacements (stresses and strains). The eventual implementation of these methodologies will result in acceleration of the industry adoption of higher-strength line-pipe steels.

  14. Significance of locally intensified strain aging to the fracture toughness of welded steel structures

    SciTech Connect (OSTI)

    Dawes, M.G.

    1995-12-31

    A review of past studies shows that tests on specimens notched after welding can give overestimates of the fracture toughness that occurs at the tips of flaws present during welding. This situation results from locally intensified straining and aging embrittlement (LISAE), which has been shown to trigger low stress brittle fractures in both notched and welded wide plate tension tests, and welded structures in service. Although the relative susceptibilities of steels to strain aging embrittlement are sometimes assessed by testing bulk strained and aged samples, the results of such tests may be optimistic. A summary is given of work to develop a fracture toughness test method for LISAE. The new test will give increased confidence and accuracy in fracture assessments, be of use in selecting tough materials, and aid the development of materials that are resistant to LISAE.

  15. Superconducting coil and method of stress management in a superconducting coil

    DOE Patents [OSTI]

    McIntyre, Peter M. (College Station, TX); Shen, Weijun (Oak Ridge, TN); Diaczenko, Nick (College Station, TX); Gross, Dan A. (College Station, TX)

    1999-01-01

    A superconducting coil (12) having a plurality of superconducting layers (18) is provided. Each superconducting layer (18) may have at least one superconducting element (20) which produces an operational load. An outer support structure (24) may be disposed outwardly from the plurality of layers (18). A load transfer system (22) may be coupled between at least one of the superconducting elements (20) and the outer support structure (24). The load transfer system (22) may include a support matrix structure (30) operable to transfer the operational load from the superconducting element (20) directly to the outer support structure (24). A shear release layer (40) may be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a shear stress between the superconducting element (20) and the support matrix structure (30). A compliant layer (42) may also be disposed, in part, between the superconducting element (20) and the support matrix structure (30) for relieving a compressive stress on the superconducting element (20).

  16. Diode laser welding of aluminum to steel

    SciTech Connect (OSTI)

    Santo, Loredana; Quadrini, Fabrizio; Trovalusci, Federica [University of Rome Tor Vergata, Department of Mechanical Engineering, Via del Politecnico 1, 00133 Rome (Italy)

    2011-05-04

    Laser welding of dissimilar materials was carried out by using a high power diode laser to join aluminum to steel in a butt-joint configuration. During testing, the laser scan rate was changed as well as the laser power: at low values of fluence (i.e. the ratio between laser power and scan rate), poor joining was observed; instead at high values of fluence, an excess in the material melting affected the joint integrity. Between these limiting values, a good aesthetics was obtained; further investigations were carried out by means of tensile tests and SEM analyses. Unfortunately, a brittle behavior was observed for all the joints and a maximum rupture stress about 40 MPa was measured. Apart from the formation of intermeltallic phases, poor mechanical performances also depended on the chosen joining configuration, particularly because of the thickness reduction of the seam in comparison with the base material.

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. Tensile Fracture of Welded Polymer Interfaces: Miscibility, Entanglements and Crazing

    E-Print Network [OSTI]

    Ting Ge; Gary S. Grest; Mark O. Robbins

    2014-10-07

    Large-scale molecular simulations are performed to investigate tensile failure of polymer interfaces as a function of welding time $t$. Changes in the tensile stress, mode of failure and interfacial fracture energy $G_I$ are correlated to changes in the interfacial entanglements as determined from Primitive Path Analysis. Bulk polymers fail through craze formation, followed by craze breakdown through chain scission. At small $t$ welded interfaces are not strong enough to support craze formation and fail at small strains through chain pullout at the interface. Once chains have formed an average of about one entanglement across the interface, a stable craze is formed throughout the sample. The failure stress of the craze rises with welding time and the mode of craze breakdown changes from chain pullout to chain scission as the interface approaches bulk strength. The interfacial fracture energy $G_I$ is calculated by coupling the simulation results to a continuum fracture mechanics model. As in experiment, $G_I$ increases as $t^{1/2}$ before saturating at the average bulk fracture energy $G_b$. As in previous simulations of shear strength, saturation coincides with the recovery of the bulk entanglement density. Before saturation, $G_I$ is proportional to the areal density of interfacial entanglements. Immiscibiltiy limits interdiffusion and thus suppresses entanglements at the interface. Even small degrees of immisciblity reduce interfacial entanglements enough that failure occurs by chain pullout and $G_I \\ll G_b$.

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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

  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. 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.

  10. 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.

  11. Recent advances in Ti and Nb explosion welding with stainless steel for 2K operating (ILC Program)- To the proceedings of LCWS11

    E-Print Network [OSTI]

    Sabirov, B; Sissakian, A; Shirkov, G; Taran, Yu; Trubnikov, G; Dhanarai, N; Foley, M; Harms, E; Mitchell, D; Nagaitsev, S; Soyars, W; Rybakov, V; Samarokov, Yu; Zhigalov, V; Basti, A; Bedeschi, F

    2012-01-01

    The world first samples 0f Ti+SS and Nb+SS joints were manufactured by an explosion welding technology demonstrating a high mechanic properties and leak absence at 4.6 x 10^{-9} atm-cc/sec. Residual stresses in bimetallic joints resulting from explosion welding measured by neutron diffraction method are quite high (~1000 MPa). Thermal tempering of explosion welded Ti+SS and Nb+SS specimens leads to complete relaxation of internal stresses in Ti,Nb and Stainless steel and makes the transition elements quite serviceable.

  12. Recent advances in Ti and Nb explosion welding with stainless steel for 2K operating (ILC Program)- To the proceedings of LCWS11

    E-Print Network [OSTI]

    B. Sabirov; J. Budagov; A. Sissakian; G. Shirkov; Yu. Taran; G. Trubnikov; N. Dhanarai; M. Foley; E. Harms; D. Mitchell; S. Nagaitsev; W. Soyars; V. Rybakov; Yu. Samarokov; V. Zhigalov; A. Basti; F. Bedeschi

    2012-01-17

    The world first samples 0f Ti+SS and Nb+SS joints were manufactured by an explosion welding technology demonstrating a high mechanic properties and leak absence at 4.6 x 10^{-9} atm-cc/sec. Residual stresses in bimetallic joints resulting from explosion welding measured by neutron diffraction method are quite high (~1000 MPa). Thermal tempering of explosion welded Ti+SS and Nb+SS specimens leads to complete relaxation of internal stresses in Ti,Nb and Stainless steel and makes the transition elements quite serviceable.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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 $\\kappa<4$.

  20. 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 $\\kappa<4$.

  1. STRESS CORROSION CRACKING IN TEAR DROP SPECIMENS

    SciTech Connect (OSTI)

    Lam, P; Philip Zapp, P; Jonathan Duffey, J; Kerry Dunn, K

    2009-05-01

    Laboratory tests were conducted to investigate the stress corrosion cracking (SCC) of 304L stainless steel used to construct the containment vessels for the storage of plutonium-bearing materials. The tear drop corrosion specimens each with an autogenous weld in the center were placed in contact with moist plutonium oxide and chloride salt mixtures. Cracking was found in two of the specimens in the heat affected zone (HAZ) at the apex area. Finite element analysis was performed to simulate the specimen fabrication for determining the internal stress which caused SCC to occur. It was found that the tensile stress at the crack initiation site was about 30% lower than the highest stress which had been shifted to the shoulders of the specimen due to the specimen fabrication process. This finding appears to indicate that the SCC initiation took place in favor of the possibly weaker weld/base metal interface at a sufficiently high level of background stress. The base material, even subject to a higher tensile stress, was not cracked. The relieving of tensile stress due to SCC initiation and growth in the HAZ and the weld might have foreclosed the potential for cracking at the specimen shoulders where higher stress was found.

  2. 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.

  3. 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...

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  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. 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....

  12. 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...

  13. 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.

  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. 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.

  17. 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.

  18. MODELING OF HIGH SPEED FRICTION STIR SPOT WELDING USING A LAGRANGIAN FINITE ELEMENT APPROACH

    SciTech Connect (OSTI)

    Miles, Michael; Karki, U.; Woodward, C.; Hovanski, Yuri

    2013-09-03

    Friction stir spot welding (FSSW) has been shown to be capable of joining steels of very high strength, while also being very flexible in terms of controlling the heat of welding and the resulting microstructure of the joint. This makes FSSW a potential alternative to resistance spot welding (RSW) if tool life is sufficiently high, and if machine spindle loads are sufficiently low so that the process can be implemented on an industrial robot. Robots for spot welding can typically sustain vertical loads of about 8kN, but FSSW at tool speeds of less than 3000 rpm cause loads that are too high, in the range of 11-14 kN. Therefore, in the current work tool speeds of 3000 rpm and higher were employed, in order to generate heat more quickly and to reduce welding loads to acceptable levels. The FSSW process was modeled using a finite element approach with the Forge® software package. An updated Lagrangian scheme with explicit time integration was employed to model the flow of the sheet material, subjected to boundary conditions of a rotating tool and a fixed backing plate [3]. The modeling approach can be described as two-dimensional, axisymmetric, but with an aspect of three dimensions in terms of thermal boundary conditions. Material flow was calculated from a velocity field which was two dimensional, but heat generated by friction was computed using a virtual rotational velocity component from the tool surface. An isotropic, viscoplastic Norton-Hoff law was used to model the evolution of material flow stress as a function of strain, strain rate, and temperature. The model predicted welding temperatures and the movement of the joint interface with reasonable accuracy for the welding of a dual phase 980 steel.

  19. 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.

  20. 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.

  1. 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...

  2. 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.

  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. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. Develop baseline computational model for proactive welding stress

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

    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 Delicious Rank EERE:FinancingPetroleum Based| Department8, 20153DanielthroughDeterminingmanagement to suppress helium

  20. Optimizing Stress

    E-Print Network [OSTI]

    Chaver, Abigail

    2013-01-01

    hardiness can help stress tolerance rise, improvingA global measure of perceived stress. Journal of Health andMaxon, Rebecca. (1999). Stress in the Workplace: A Costly

  1. 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.

  2. 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.

  3. Directory

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

    122410 4:52 AM Send Document Link Develpo Baseline Computational Model for Proactive Welding Stress Management to Suppress Helium-Induced Cracking During Weld Repair Develpo...

  4. 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.

  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. 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.

  8. 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.

  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. 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.

  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. Temperature and Material Flow Prediction in Friction-Stir Spot Welding of Advanced High-Strength Steel

    SciTech Connect (OSTI)

    Miles, Michael; Karki, U.; Hovanski, Yuri

    2014-10-01

    Friction-stir spot welding (FSSW) has been shown to be capable of joining advanced high-strength steel, with its flexibility in controlling the heat of welding and the resulting microstructure of the joint. This makes FSSW a potential alternative to resistance spot welding if tool life is sufficiently high, and if machine spindle loads are sufficiently low that the process can be implemented on an industrial robot. Robots for spot welding can typically sustain vertical loads of about 8 kN, but FSSW at tool speeds of less than 3000 rpm cause loads that are too high, in the range of 11–14 kN. Therefore, in the current work, tool speeds of 5000 rpm were employed to generate heat more quickly and to reduce welding loads to acceptable levels. Si3N4 tools were used for the welding experiments on 1.2-mm DP 980 steel. The FSSW process was modeled with a finite element approach using the Forge* software. An updated Lagrangian scheme with explicit time integration was employed to predict the flow of the sheet material, subjected to boundary conditions of a rotating tool and a fixed backing plate. Material flow was calculated from a velocity field that is two-dimensional, but heat generated by friction was computed by a novel approach, where the rotational velocity component imparted to the sheet by the tool surface was included in the thermal boundary conditions. An isotropic, viscoplastic Norton-Hoff law was used to compute the material flow stress as a function of strain, strain rate, and temperature. The model predicted welding temperatures to within percent, and the position of the joint interface to within 10 percent, of the experimental results.

  14. Laboratory testing of cement grouting of fractures in welded tuff

    SciTech Connect (OSTI)

    Sharpe, C.J.; Daemen, J.J.

    1991-03-01

    Fractures in the rock mass surrounding a repository and its shafts, access drifts, emplacement rooms and holes, and exploratory or in-situ testing holes, may provide preferential flowpaths for the flow of groundwater or air, potentially containing radionuclides. Such cracks may have to be sealed. The likelihood that extensive or at least local grouting will be required as part of repository sealing has been noted in numerous publications addressing high level waste repository closing. The objective of this work is to determine the effectiveness of fracture sealing (grouting) in welded tuff. Experimental work includes measurement of intact and fracture permeability under various normal stresses and injection pressures. Grout is injected into the fractures. The effectiveness of grouting is evaluated in terms of grout penetration and permeability reduction, compared prior to and after grouting. Analysis of the results include the effect of normal stress, injection pressure, fracture roughness, grout rheology, grout bonding, and the radial extent of grout penetration. Laboratory experiments have been performed on seventeen tuff cylinders with three types of fractures: (1) tension induced cracks, (2) natural fractures, and (3) sawcuts. Prior to grouting, the hydraulic conductivity of the intact rock and of the fractures is measured under a range of normal stresses. The surface topography of the fracture is mapped, and the results are used to determine aperture distributions across the fractures. 72 refs., 76 figs., 25 tabs.

  15. 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

  16. 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

  17. 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....

  18. 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...

  19. management

    National Nuclear Security Administration (NNSA)

    5%2A en Management and Budget http:www.nnsa.energy.govaboutusouroperationsmanagementandbudget

  20. 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 

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. 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.

  12. Waterside Stress Assisted Corrosion (SAC) of Boiler Tubes

    E-Print Network [OSTI]

    Das, Suman

    Waterside Stress Assisted Corrosion (SAC) of Boiler Tubes School of Materials Science Boiler Areas Susceptible to SAC · Generally SAC initiates near weld joints on cold side of tubes · SAC cracks are difficult to detect inaccessibility · Failures Detected at Various Locations in Boilers

  13. 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.

  14. 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

  15. 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.

  16. 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).

  17. 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.

  18. Poverty & Stress

    E-Print Network [OSTI]

    Jani, Neel

    2013-01-01

    Raises Levels of the Stress Hormone Cortisol: Evidence fromSubtypes of Neglect and Stress as a Mediator. Spencer, N. (poor but somehow evade the stress of poverty perform just as

  19. Surge Nozzle NDE Specimen Mechanical Stress Improvement Analysis

    SciTech Connect (OSTI)

    Fredette, Lee F.

    2011-07-14

    The purpose of this project was to perform a finite element analysis of a pressurized water reactor pressurizer surge nozzle mock-up to predict both the weld residual stresses created in its construction and the final stress state after the application of the Mechanical Stress Improvement Process (MSIP). Strain gages were applied to the inner diameter of the mock-up to record strain changes during the MSIP. These strain readings were used in an attempt to calculate the final stress state of the mock-up as well.

  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. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  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. Crack growth rates of irradiated austenitic stainless steel weld heat affected zone in BWR environments.

    SciTech Connect (OSTI)

    Chopra, O. K.; Alexandreanu, B.; Gruber, E. E.; Daum, R. S.; Shack, W. J.; Energy Technology

    2006-01-31

    Austenitic stainless steels (SSs) are used extensively as structural alloys in the internal components of reactor pressure vessels because of their superior fracture toughness. However, exposure to high levels of neutron irradiation for extended periods can exacerbate the corrosion fatigue and stress corrosion cracking (SCC) behavior of these steels by affecting the material microchemistry, material microstructure, and water chemistry. Experimental data are presented on crack growth rates of the heat affected zone (HAZ) in Types 304L and 304 SS weld specimens before and after they were irradiated to a fluence of 5.0 x 10{sup 20} n/cm{sup 2} (E > 1 MeV) ({approx} 0.75 dpa) at {approx}288 C. Crack growth tests were conducted under cycling loading and long hold time trapezoidal loading in simulated boiling water reactor environments on Type 304L SS HAZ of the H5 weld from the Grand Gulf reactor core shroud and on Type 304 SS HAZ of a laboratory-prepared weld. The effects of material composition, irradiation, and water chemistry on growth rates are discussed.

  12. Specified pipe fittings susceptible to sulfide stress cracking

    SciTech Connect (OSTI)

    McIntyre, D.R.; Moore, E.M. Jr. [Saudi Aramco, Dhahran (Saudi Arabia)

    1996-01-01

    The NACE Standard MR0175 limit of HRC 22 is too high for cold-forged and stress-relieved ASTM A234 WPB pipe fittings. Hardness surveys and sulfide stress cracking test results per ASTM G 39 and NACE TM0177 Method B are presented to support this contention. More stringent inspection and a hardness limit of HB 197 (for cold-forged and stress-relieved fittings only) are recommended. The paper describes a case in which fittings were welded in place in wet sour service flow lines and gas-oil separating plants which were ready to start. The failure of a welded fitting shortly after start-up led to extensive field hardness testing on all fittings from this manufacturer.

  13. 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.

  14. 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.

  15. 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.

  16. 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...

  17. 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. ...

  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. 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.

  20. 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...

  1. 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.

  2. 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...

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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

  1. On-Line Weld NDE with IR Thermography | Department of Energy

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE'sManagement ofOh,ofOn-Line Weld NDE with IR

  2. Online Weld Quality NDE & Control with IR Thermography | Department of

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

    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 Delicious RankADVANCED MANUFACTURINGEnergy Bills and ReduceNovemberDOE'sManagement ofOh,ofOn-LineEnergy Online Weld

  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. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Welding Metallurgy and Processing Issues for Joining of Power Sources

    SciTech Connect (OSTI)

    Lienert, Thomas J. [Los Alamos National Laboratory; Reardon, Patrick T. [Los Alamos National Laboratory

    2012-08-14

    Weldability issues with the pertinent alloys have been reviewed and preliminary results of our work on Haynes 25 have been presented. Further results on the mechanical properties and metallography on the EB welds are imminent. Hot-ductility experiments will commence within a few weeks. Aging studies on the effects of heat treatment using the Gleeble are also planned. MST-6 has extensive background in the welding metallurgy of the pertinent alloys. We also have considerable experience with the various welding processes to be used.

  11. Welding fixture for nuclear fuel pin cladding assemblies

    DOE Patents [OSTI]

    Oakley, D.J.; Feld, S.H.

    1984-02-22

    A welding fixture is described for locating a driver sleeve about the open end of a nuclear fuel pin cladding. The welding fixture includes a holder provided with an open cavity having shoulders for properly positioning the driver sleeve, the end cap, and a soft, high temperature resistant plastic protective sleeve that surrounds a portion of the end cap stem. Ejected contaminant particles spewed forth by closure of the cladding by pulsed magnetic welding techniques are captured within a contamination trap formed in the holder for ultimate removal and disposal of contaminating particles along with the holder.

  12. 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.

  13. 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.

  14. Welding fixture for nuclear fuel pin cladding assemblies

    DOE Patents [OSTI]

    Oakley, David J. (Richland, WA); Feld, Sam H. (West Richland, WA)

    1986-01-01

    A welding fixture for locating a driver sleeve about the open end of a nuclear fuel pin cladding. The welding fixture includes a holder provided with an open cavity having shoulders for properly positioning the driver sleeve, the end cap, and a soft, high temperature resistant plastic protective sleeve that surrounds a portion of the end cap stem. Ejected contaminant particles spewed forth by closure of the cladding by pulsed magnetic welding techniques are captured within a contamination trap formed in the holder for ultimate removal and disposal of contaminating particles along with the holder.

  15. Inspection apparatus for evaluating a partially completed weld

    DOE Patents [OSTI]

    Smartt, Herschel B. (Idaho Falls, ID); Larsen, Eric D. (Idaho Falls, ID); Johnson, Jonn A. (Idaho Falls, ID)

    2001-01-01

    An inspection apparatus for evaluating a partially completed weld is described and which is utilized in combination with an automated movable welder which moves across a supporting surface, and wherein the inspection apparatus includes a coupling member mounted on the welder; a frame member mounted on the coupling member; an ultrasonic sensor mounted on the frame member and disposed in ultrasonic sound transmitting relation relative to the partially completed weld; and a drive assembly for adjusting the position of the ultrasonic sensor relative to the partially completed weld.

  16. Addressing employee concerns about welding in a nuclear power plant

    SciTech Connect (OSTI)

    Danko, J.C.; Hansen, D.D.; O'Leary, P.D.

    1988-03-01

    A leading utility contracted with EG and G Idaho to perform a comprehensive, independent evaluation of the utility's welding program with respect to the safety-related welds made at one of its nuclear power plants. The purpose of this paper is to review a number of the employee concerns and the technical basis for the disposition of these concerns. In addition, recommendations are presented that may help to prevent the recurrence of employee concerns in future nuclear power plant construction, and thereby costly delays may be avoided and welding productivity and quality improved.

  17. OPTIMIZATION STUDY FOR FILL STEM MANUFACTURINGAND PINCH WELD PROCESSING

    SciTech Connect (OSTI)

    Korinko, P; Karl Arnold, K

    2006-09-06

    A statistically designed experiment was conducted as part of a six sigma project for Fill Stem Manufacturing and Pinch Weld Processing. This multi-year/multi-site project has successfully completed a screening study and used those results as inputs to this optimization study. Eleven welds were made using fairly tight current and cycle range. The welds demonstrate increased burst strength, longer closure length, more net displacement, and improved bond rating with increased current. However, excessive melting remains a concern from a processing viewpoint and may cause adverse metallurgical interactions. Therefore, the highest current levels specified cannot be utilized. A Validation Study is proposed for the Defense Programs Inert Facility.

  18. 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.

  19. 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.

  20. POTENTIAL FOR STRESS CORROSION CRACKING OF A537 CARBON STEEL NUCLEAR WASTE TANKS CONTAINING HIGHLY CAUSTIC SOLUTIONS

    SciTech Connect (OSTI)

    Lam, P.; Stripling, C.; Fisher, D.; Elder, J.

    2010-04-26

    The evaporator recycle streams of nuclear waste tanks may contain waste in a chemistry and temperature regime that exceeds the current corrosion control program, which imposes temperature limits to mitigate caustic stress corrosion cracking (CSCC). A review of the recent service history found that two of these A537 carbon steel tanks were operated in highly concentrated hydroxide solution at high temperature. Visual inspections, experimental testing, and a review of the tank service history have shown that CSCC has occurred in uncooled/un-stress relieved tanks of similar construction. Therefore, it appears that the efficacy of stress relief of welding residual stress is the primary corrosion-limiting mechanism. The objective of this experimental program is to test A537 carbon steel small scale welded U-bend specimens and large welded plates (30.48 x 30.38 x 2.54 cm) in a caustic solution with upper bound chemistry (12 M hydroxide and 1 M each of nitrate, nitrite, and aluminate) and temperature (125 C). These conditions simulate worst-case situations in these nuclear waste tanks. Both as-welded and stress-relieved specimens have been tested. No evidence of stress corrosion cracking was found in the U-bend specimens after 21 days of testing. The large plate test was completed after 12 weeks of immersion in a similar solution at 125 C except that the aluminate concentration was reduced to 0.3 M. Visual inspection of the plate revealed that stress corrosion cracking had not initiated from the machined crack tips in the weld or in the heat affected zone. NDE ultrasonic testing also confirmed subsurface cracking did not occur. Based on these results, it can be concluded that the environmental condition of these tests was unable to develop stress corrosion cracking within the test periods for the small welded U-bends and for the large plates, which were welded with an identical procedure as used in the construction of the actual nuclear waste tanks in the 1960s. The absence of evidence of stress corrosion cracking and general corrosion in the laboratory-scaled specimens indicate that this type of nuclear waste tank is not susceptible to highly caustic solutions up to 12 M hydroxide at 125 C when sufficient nitrite inhibitor is present.

  1. Modeling of the Thermal Field in Dissimilar Alloy Ultrasonic Welding

    E-Print Network [OSTI]

    Jedrasiak, P.; Shercliff, H. R.; Chen, Y. C.; Wang, L.; Prangnell, P.; Robson, J.

    2014-12-10

    This paper describes a finite element model for predicting the temperature field in high power ultrasonic welding aluminum AA6111 to two dissimilar alloys, magnesium AZ31, and low carbon steel DC04. Experimental thermocouple and other evidence...

  2. FINITE ELEMENT ANALYSIS OF STEEL WELDED COVERPLATE INCLUDING COMPOSITE DOUBLERS

    E-Print Network [OSTI]

    Petri, Brad

    2008-05-15

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

  3. 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.

  4. Promising Inspection Technique for Vehicle Welding Offers Efficient...

    Office of Environmental Management (EM)

    technology that could check all welds in real-time on the production line. This new technology could make this process faster and more efficient, allowing vehicles to be...

  5. STRUCTURAL HEALTH MONITORING OF WELDED CONNECTIONS

    SciTech Connect (OSTI)

    H. SOHN; C. FARRAR; M. FUGATE; J. CZARNECKI

    2001-05-01

    Structural health monitoring is the implementation of a damage detection strategy for aerospace, civil and mechanical engineering infrastructure. Typical damage experienced by this infrastructure might be the development of fatigue cracks, degradation of structural connections, or bearing wear in rotating machinery. The goal of the research effort reported herein is to develop a robust and cost-effective monitoring system for welded beam-column connections in a moment resisting frame structure. The structural health monitoring solution for this application will integrate structural dynamics, wireless data acquisition, local actuation, micro-electromechanical systems (MEMs) technology, and statistical pattern recognition algorithms. This paper provides an example of the integrated approach to structural health monitoring being undertaken at Los Alamos National Laboratory and summarizes progress to date on various aspects of the technology development.

  6. 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.

  7. 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.

  8. Design method addresses subsea pipeline thermal stresses

    SciTech Connect (OSTI)

    Suman, J.C.; Karpathy, S.A. )

    1993-08-30

    Managing thermal stresses in subsea pipelines carrying heated petroleum requires extensive thermal-stress analysis to predict trouble spots and to ensure a design flexible enough to anticipate stresses and expansions. Explored here are various methods for resolving predicaments posed by thermal loads and resulting deformations by keeping the stresses and deformations in the pipeline system within allowable limits. The problems posed by thermal stresses are not unique; the solutions proposed here are. These methods are based on recent work performed for a major Asian subsea pipeline project currently under construction.

  9. 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.

  10. Effect of heat input on the microstructure, residual stresses and corrosion resistance of 304L austenitic stainless steel weldments

    SciTech Connect (OSTI)

    Unnikrishnan, Rahul, E-mail: rahulunnikrishnannair@gmail.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India); Idury, K.S.N. Satish, E-mail: satishidury@gmail.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India); Ismail, T.P., E-mail: tpisma@gmail.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India); Bhadauria, Alok, E-mail: alokbhadauria1@gmail.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India); Shekhawat, S.K., E-mail: satishshekhawat@gmail.com [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay (IITB), Powai, Mumbai 400076, Maharashtra (India); Khatirkar, Rajesh K., E-mail: rajesh.khatirkar@gmail.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India); Sapate, Sanjay G., E-mail: sgsapate@yahoo.com [Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), South Ambazari Road, Nagpur 440010, Maharashtra (India)

    2014-07-01

    Austenitic stainless steels are widely used in high performance pressure vessels, nuclear, chemical, process and medical industry due to their very good corrosion resistance and superior mechanical properties. However, austenitic stainless steels are prone to sensitization when subjected to higher temperatures (673 K to 1173 K) during the manufacturing process (e.g. welding) and/or certain applications (e.g. pressure vessels). During sensitization, chromium in the matrix precipitates out as carbides and intermetallic compounds (sigma, chi and Laves phases) decreasing the corrosion resistance and mechanical properties. In the present investigation, 304L austenitic stainless steel was subjected to different heat inputs by shielded metal arc welding process using a standard 308L electrode. The microstructural developments were characterized by using optical microscopy and electron backscattered diffraction, while the residual stresses were measured by X-ray diffraction using the sin{sup 2}? method. It was observed that even at the highest heat input, shielded metal arc welding process does not result in significant precipitation of carbides or intermetallic phases. The ferrite content and grain size increased with increase in heat input. The grain size variation in the fusion zone/heat affected zone was not effectively captured by optical microscopy. This study shows that electron backscattered diffraction is necessary to bring out changes in the grain size quantitatively in the fusion zone/heat affected zone as it can consider twin boundaries as a part of grain in the calculation of grain size. The residual stresses were compressive in nature for the lowest heat input, while they were tensile at the highest heat input near the weld bead. The significant feature of the welded region and the base metal was the presence of a very strong texture. The texture in the heat affected zone was almost random. - Highlights: • Effect of heat input on microstructure, residual stresses and corrosion is studied. • HAZ and width of dendrite in the welded region increase with heat input. • Residual stresses are tensile near the welded region after the highest heat input. • Welded region has the highest pit density after highest heat input. • Dendrites and ?-ferrite were highly oriented in the welded region.

  11. Stress analysis and evaluation of a rectangular pressure vessel...

    Office of Scientific and Technical Information (OSTI)

    States)) 42 ENGINEERING; 12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; PRESSURE VESSELS; STRESS ANALYSIS; RADIOACTIVE WASTE STORAGE;...

  12. 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...

  13. 1. WELDING TO BE PERFORMED IN ACCORDANCE WITH ASME SECTION IX. NO CODE STAMP REQUIRED.

    E-Print Network [OSTI]

    McDonald, Kirk

    45° W-1 3/16 G NOTES 1. WELDING TO BE PERFORMED IN ACCORDANCE WITH ASME SECTION IX. NO CODE STAMP REQUIRED. 2. ALL WELDS SHALL BE DYE PENETRANT INSPECTED. NO RADIOGRAPHY REQUIRED. 3. MATERIAL

  14. The hardening of Type 316L stainless steel welds with thermal aging

    E-Print Network [OSTI]

    Ayers, Lauren Juliet

    2012-01-01

    Welded stainless steel piping is a component of boiling water reactors (BWRs). Reirculation and other large diameter piping are fabricated from Type 304 or 316 stainless steels. Delta ferrite is present in welds, because ...

  15. 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...

  16. Crowdsourcing Control: Moving Beyond Multiple Choice Christopher H. Lin Mausam Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Crowdsourcing Control: Moving Beyond Multiple Choice Christopher H. Lin Mausam Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195 {chrislin,mausam,weld, and Weld 2010; 2011) to quality control is the restriction to multiple choice questions, i.e., jobs where

  17. Solving Relational MDPs with First-Order Machine Learning Mausam and Daniel S. Weld

    E-Print Network [OSTI]

    Solving Relational MDPs with First-Order Machine Learning£ Mausam and Daniel S. Weld Dept of Computer Science and Engineering University of Washington Seattle, WA-98195 {mausam,weld (Peot & Smith 1992; Etzioni et al. 1992; Pryor & Collins 1996; Goldman & Boddy 1994; Smith & Weld 1998

  18. Decision-Theoretic User Interface Generation Krzysztof Z. Gajos and Daniel S. Weld

    E-Print Network [OSTI]

    Wobbrock, Jacob O.

    Decision-Theoretic User Interface Generation Krzysztof Z. Gajos and Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195, USA {kgajos,weld interfaces and developing efficient algorithms for their automatic generation (Gajos & Weld, 2004; Gajos et

  19. Physical processes involved in strip electrode welding using the method of slatted splicing

    SciTech Connect (OSTI)

    Bushma, V. O. [Moscow State Technological University 'Stankin' (Russian Federation)

    2010-12-15

    Physical processes that take place in a strip electrode during welding using the slatted splicing technique are considered. Flowing of the welding current in the electrode is shown to be the key process which determines electrode heating and melting. Technological receipts are proposed that allow obtaining high-quality welds by the method of slatted splicing.

  20. High-Performance and Low-Cost Dual-Thread VLIW Processor Using Weld

    E-Print Network [OSTI]

    Conte, Thomas M.

    High-Performance and Low-Cost Dual-Thread VLIW Processor Using Weld Architecture Paradigm Emre O-performance dual-thread VLIW processor model. The dual-thread VLIW processor model is a low-cost subset of the Weld runtime events. The general Weld architectural model is proposed as a statically scheduled, horizontal

  1. Least-Commitment Action Selection Marc Friedman and Daniel S. Weld

    E-Print Network [OSTI]

    Least-Commitment Action Selection Marc Friedman and Daniel S. Weld Department of Computer Science and Engineering University of Washington Box 352350 Seattle, WA 98195-2350 friedman, weld on formalizing partial-order planning algo- rithms (Chapman 1987; McAllester & Rosenblitt 1991; Hanks & Weld 1995

  2. Learning 5000 Relational Extractors Raphael Hoffmann, Congle Zhang, Daniel S. Weld

    E-Print Network [OSTI]

    Anderson, Richard

    Learning 5000 Relational Extractors Raphael Hoffmann, Congle Zhang, Daniel S. Weld Computer Science & Engineering University of Washington Seattle, WA-98195, USA {raphaelh,clzhang,weld}@cs.washington.edu Abstract and Kumlien, 1999). With the Kylin system (Wu and Weld, 2007) ap- plied this idea to Wikipedia by matching

  3. Solving Relational MDPs with First-Order Machine Learning Mausam and Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Solving Relational MDPs with First-Order Machine Learning Mausam and Daniel S. Weld Dept of Computer Science and Engineering University of Washington Seattle, WA-98195 {mausam,weld (Peot & Smith 1992; Etzioni et al. 1992; Pryor & Collins 1996; Goldman & Boddy 1994; Smith & Weld 1998

  4. Cross-sectional Views of 90/90 Pipe Without/With a Weld

    E-Print Network [OSTI]

    McDonald, Kirk

    Cross-sectional Views of 90/90 Pipe Without/With a Weld Yan 9-20-2012 #12;Outlines · Define the Locations of the Profiles · Pipe without A Weld (#Grid = 0.8×106) ­ Display in Tecplot: Figs.(a) ­ Display in FLUENT: Figs.(b) · Contours of Turbulence Intensity in Tecplot ­ Pipe with A Weld (#Grid = 1

  5. Concurrent Probabilistic Temporal Planning : Initial Results Mausam and Daniel S. Weld

    E-Print Network [OSTI]

    Concurrent Probabilistic Temporal Planning : Initial Results Mausam and Daniel S. Weld Dept of Computer Science and Engineering University of Washington Seattle, WA-98195 {mausam,weld & Weld 2004)) to efficiently solve concurrent MDPs with actions of unit length. The focus of this paper

  6. Fine-Grained Entity Recognition Xiao Ling and Daniel S. Weld

    E-Print Network [OSTI]

    Anderson, Richard

    Fine-Grained Entity Recognition Xiao Ling and Daniel S. Weld Department of Computer Science and Engineering University of Washington Seattle, WA 98195-2350, U.S.A. {xiaoling, weld are common when extracting hundreds or thousands of different relations (Hoffmann, Zhang, and Weld 2010

  7. Stochastic Shortest Path MDPs with Dead Ends Andrey Kolobov Mausam Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Stochastic Shortest Path MDPs with Dead Ends Andrey Kolobov Mausam Daniel S. Weld {akolobov, mausam, weld}@cs.washington.edu Dept of Computer Science and Engineering University of Washington Seattle, USA algorithms that are aware of the possible presence of dead-end states (Kolobov, Mausam, and Weld 2010

  8. Concurrent Probabilistic Temporal Planning : Initial Results Mausam and Daniel S. Weld

    E-Print Network [OSTI]

    Mausam

    Concurrent Probabilistic Temporal Planning : Initial Results Mausam and Daniel S. Weld Dept of Computer Science and Engineering University of Washington Seattle, WA­98195 {mausam,weld & Weld 2004)) to efficiently solve concurrent MDPs with actions of unit length. The focus of this paper

  9. Challenges for Temporal Planning with Uncertain Durations Mausam and Daniel S. Weld

    E-Print Network [OSTI]

    Challenges for Temporal Planning with Uncertain Durations Mausam and Daniel S. Weld Dept of Computer Science and Engineering University of Washington Seattle, WA-98195 {mausam,weld temporal model is used in TGP (Smith & Weld 1999). TGP-style actions require preconditions to be true

  10. 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

  11. Thermocapillary and Magnetohydrodynamic Effects in Modelling the Thermodynamics of Stationary Welding Processes

    E-Print Network [OSTI]

    Taylor, Gary

    Welding Processes Michael HUGHES, Gareth A. TAYLOR and Koulis PERICLEOUS Centre for Numerical Modelliqng transport and solidification in a stationary axisymmetric weld pool. The PHOENICS implementations, the integration of the effects within the fluid dynamics of an axisymmetric weld pool is compared against

  12. RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS

    E-Print Network [OSTI]

    Guo, Zhixiong "James"

    RADIATION HEAT TRANSFER IN TISSUE WELDING AND SOLDERING WITH ULTRAFAST LASERS Kyunghan Kim to incorporate transient radiation heat transfer in tissue welding and soldering with use of ultrafast lasers are performed between laser welding and laser soldering. The use of solder is found to substantially enhance

  13. 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

  14. Welding processes in volcanology: insights from field, experimental, and modeling studies

    E-Print Network [OSTI]

    Russell, Kelly

    Welding processes in volcanology: insights from field, experimental, and modeling studies Anita This volume is a collection of ten papers largely derived from a special session, Welding Processes, experimental, and modeling studies. We briefly review advances in understanding welding as represented

  15. Process Modeling of Ti-6Al-4V Linear Friction Welding (LFW)

    E-Print Network [OSTI]

    Grujicic, Mica

    Process Modeling of Ti-6Al-4V Linear Friction Welding (LFW) Mica Grujicic, G. Arakere, B finite-element analysis of the linear friction welding (LFW) process is combined with the basic physical in the open literature revealed that the weld region consists of a thermo- mechanically affected zone (TMAZ

  16. 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

  17. 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

  18. Rheology of welding: inversion of field constraints James K. Russell*, Steven L. Quane

    E-Print Network [OSTI]

    Russell, Kelly

    Rheology of welding: inversion of field constraints James K. Russell*, Steven L. Quane Igneous the mechanisms and rheological behaviour of pyroclastic deposits during welding and compaction are poorly are constrained by physical property distributions in welded ignimbrite. Physical properties of samples from a 20

  19. Review: friction stir welding tools , H. K. D. H. Bhadeshia3

    E-Print Network [OSTI]

    Cambridge, University of

    Review: friction stir welding tools R. Rai1 , A. De2 , H. K. D. H. Bhadeshia3 and T. DebRoy*1 Friction stir welding (FSW) is a widely used solid state joining process for soft materials such as aluminium alloys because it avoids many of the common problems of fusion welding. Commercial feasibility

  20. Induction welding and heat treatment of steel pipes: evolution of crystallographic texture

    E-Print Network [OSTI]

    Cambridge, University of

    Induction welding and heat treatment of steel pipes: evolution of crystallographic texture detrimental to toughness P. Yan*1 , O¨. E. Gu¨ngo¨r2 , P. Thibaux2 and H. K. D. H. Bhadeshia1 Steel welding using induction heating to produce pipelines is found to have lower toughness at the weld junction than

  1. Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field

    E-Print Network [OSTI]

    Collins, Gary S.

    Friction Stir Welding of Hydrided Titanium Alloys Mark Taylor, D.P. Field Multi-Scale Engineering for Undergraduates program under grant number EEC-0754370 During Friction Stir Welding (FSW), a non-consumable tool-state welding process, much frictional heating and force is required of the tool. This steep demand on the tool

  2. WELDING INSPECTION USING NOVEL SPECULARITY FEATURES AND A ONE-CLASS SVM

    E-Print Network [OSTI]

    WELDING INSPECTION USING NOVEL SPECULARITY FEATURES AND A ONE-CLASS SVM Fabian Timm, Sascha Klement extraction, One-class classification, Welding seam inspection, Machine vision. Abstract: We present a framework for automatic inspection of welding seams based on specular reflections. Therefore, we introduce

  3. Problems in the Welding of Automotive Alloys H. K. D. H. Bhadeshia

    E-Print Network [OSTI]

    Cambridge, University of

    Editorial Problems in the Welding of Automotive Alloys H. K. D. H. Bhadeshia Many thousands incomplete and it is common to ignore the fact that welding is an essential component of auto- mobile service. It is not surprising that the highly successful dual phase steels3 can be welded using resistance

  4. Computational Investigation of Hardness Evolution During Friction-Stir Welding of AA5083 and AA2139

    E-Print Network [OSTI]

    Grujicic, Mica

    Computational Investigation of Hardness Evolution During Friction-Stir Welding of AA5083 and AA2139 coupled thermo-mechanical finite-element analysis of the friction-stir welding (FSW) process developed, finite-element analysis, friction- stir welding, hardness prediction 1. Introduction Having a more mobile

  5. 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

  6. VBGVBG3/7/2006MODIFIED LEAK DETECTOR BRACKET1 2. WELDING & INSPECTIONS SHALL BE PERFORMED

    E-Print Network [OSTI]

    McDonald, Kirk

    VBGVBG3/7/2006MODIFIED LEAK DETECTOR BRACKET1 APPROVED 2. WELDING & INSPECTIONS SHALL BE PERFORMED 4. MATERIAL CERTIFICATIONS REQUIRED 3. ALL WELDS SHALL BE DYE PENETRANT INSPECTED IN ACCORDANCE WITH AWS D.1.6 1 1. ALL WELDS MUST BE WATERTIGHT NOTES BYDATEDESCRIPTIONREV ITEM NO. QTY. DESCRIPTION

  7. 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

  8. A functional-analytic proof of the conformal welding Eric Schippers1 Wolfgang Staubach 2

    E-Print Network [OSTI]

    Schippers, Eric

    A functional-analytic proof of the conformal welding theorem Eric Schippers1 Wolfgang Staubach 2 1 Universitet Uppsala, Sweden CMS Winter Meeting 2012 Eric Schippers (Manitoba) Conformal welding theorem CMS Winter Meeting 2012 1 / 21 #12;Statement of the theorem Conformal welding theorem Definition

  9. A Walk-Through Programmed Robot for Welding in Shipyards Marcelo H. Ang Jr.*, Wei Lin#

    E-Print Network [OSTI]

    Ang Jr.,, Marcelo H.

    1 A Walk-Through Programmed Robot for Welding in Shipyards Marcelo H. Ang Jr.*, Wei Lin# and Ser: · Walk-through programming · Robotic welding · Automation in shipyards · Dynamic control Industrial Robot, Vol. 26, No. 5, 1999, pp. 377-388. #12;1 A Walk-Through Programmed Robot for Welding in Shipyards

  10. The Geometry of Intersecting Tubes Applied to Controlling a Robotic Welding Torch

    E-Print Network [OSTI]

    Stockie, John

    The Geometry of Intersecting Tubes Applied to Controlling a Robotic Welding Torch John M. Stockie Abstract: The question of how to control a robotic welding torch to trace the joint between two cylindrical that increase its applicability to more advanced mathematics courses. Keywords: pipe welding, cylinders

  11. Welding: insights from high-temperature analogue experiments Steven L. Quane, J.K. Russell*

    E-Print Network [OSTI]

    Russell, Kelly

    Welding: insights from high-temperature analogue experiments Steven L. Quane, J.K. Russell* Igneous of pyroclastic deposits during welding is incompletely understood and is based on a surprisingly small number roles of emplacement temperature, load and glass transition temperature in welding of pyroclastic

  12. 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

  13. Modeling of AA5083 Material-Microstructure Evolution During Butt Friction-Stir Welding

    E-Print Network [OSTI]

    Grujicic, Mica

    Modeling of AA5083 Material-Microstructure Evolution During Butt Friction-Stir Welding M. Grujicic yet a fairly comprehensive overview of the friction stir welding (FSW) process is provided-element procedure developed in our prior study. Particular attention is given to proper modeling of the welding work

  14. IDENTIFICATION NUMBER: 4ME20 Abstract--Artificial welding of melt-textured YBCO blocks

    E-Print Network [OSTI]

    Amoros, Jaume

    1 IDENTIFICATION NUMBER: 4ME20 Abstract--Artificial welding of melt-textured YBCO blocks opens the superconducting quality of the welds, we have developed a Hall probe mapping system, able to record the local to characterize welded samples prepared with a new Ag induced surface melting joining technique. The magnetization

  15. 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

  16. FINITE VOLUME METHODS APPLIED TO THE COMPUTATIONAL MODELLING OF WELDING PHENOMENA

    E-Print Network [OSTI]

    Taylor, Gary

    1 FINITE VOLUME METHODS APPLIED TO THE COMPUTATIONAL MODELLING OF WELDING PHENOMENA Gareth A.Taylor@brunel.ac.uk ABSTRACT This paper presents the computational modelling of welding phenomena within a versatile numerical) and Computational Solid Mechanics (CSM). With regard to the CFD modelling of the weld pool fluid dynamics, heat

  17. 1. WELDING SHALL BE PERFORMED IN ACCORDANCE WITH ASME SECTION IX. NO CODE STAMP REQUIRED.

    E-Print Network [OSTI]

    McDonald, Kirk

    NOTES 1. WELDING SHALL BE PERFORMED IN ACCORDANCE WITH ASME SECTION IX. NO CODE STAMP REQUIRED. 2. ALL WELDS SHALL BE DYE PENETRANT INSPECTED. NO RADIOGRAPHY REQUIRED. 3. MATERIAL CERTIFICATIONS HOSE W/TUBING ENDS, 13.5 FACE-TO-FACE N/A 3 1 swagelok 1.0 pipe weld connector SS - 316L SWAGELOK PIPE

  18. Computational Analysis of Material Flow During Friction Stir Welding of AA5059 Aluminum Alloys

    E-Print Network [OSTI]

    Grujicic, Mica

    Computational Analysis of Material Flow During Friction Stir Welding of AA5059 Aluminum Alloys M welding (FSW) process are investigated computationally. Within the numerical model of the FSW process component. The employed coupled Eulerian/Lagrangian computational analysis of the welding process

  19. SF 2001-WLD (11-2012) Supersedes (4-2010) Issue CONTRACTOR WELDING, CUTTING, BRAZING

    E-Print Network [OSTI]

    Siefert, Chris

    SF 2001-WLD (11-2012) Supersedes (4-2010) Issue CONTRACTOR WELDING, CUTTING, BRAZING PART 1: CONTRACTOR'S EXPOSURE ASSESSMENT Identify what welding, cutting and/or brazing you are doing: (Check box or fill-in type below) Welding Thermal Cutting Brazing (No cadmium filler BAg-1 or BAg- 2; Silver

  20. 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.

  1. Subsea pipeline gets welded branch without halting flow

    SciTech Connect (OSTI)

    West, A.; Hutt, G.; Starsmore, R.

    1995-12-11

    In October 1994, a 16 in. welded branch was installed without interruption to production onto Wintershall Noordzee BV`s 36-in. gas pipeline from the K13-A platform in the Dutch sector of the North Sea to Den helder, The Netherlands. The procedure is the first successfully to combine hyperbaric welding and subsea hot tapping without interruption to production. Developers of new fields can now consider exporting product without interrupting existing production and through existing infrastructure even if no convenient tie-in locations exist. Unocal evaluated export options and established that the most attractive alternative was to export gas into the Wintershall 36-in. K13-A to Den Helder pipeline. Various options for installing a branch included the following: flooding the pipeline and installing a conventional tee; stopping production and installing a welded branch followed by hot tapping; and continuing production and installing a welded branch followed by hot tapping. The chosen scheme was to retrofit a subsea side-tap assembly. This was achieved by installation of a welded branch followed by hot tapping into the 36-in. pipeline. The paper describes location determination, schedules, onshore preparation, and offshore work.

  2. FILL STEM MANUFACTURING CHANGES AND PINCH WELD QUALIFICATIONS

    SciTech Connect (OSTI)

    Korinko, P; David Maxwell, D

    2008-02-22

    In March of 2007 a document was issued, see attachment I, that defined the test protocol and required welding for the Kansas City Plant to change cutting oils from the recently approved 50:50 oil to an oil with similar characteristics but with different chemistry, additives, and possibly a different vendor due to plans by the current vendor to stop preparing the oils that are used in the KCP 50:50 mix. The KCP manufactured stems with the existing 50:50 oil blend in late FY07 and SRNL welded the stems and evaluated them in agreement with the test plan. This report provides all the data from these set-up and test welds. Set-up welds were shot and low and high voltages (currents) to ensure the window limits were applicable and then additional welds were made to validate the window. The purpose of this report is to ensure that the agreed upon path forward is still applicable.

  3. Method and device for controlling plume during laser welding

    DOE Patents [OSTI]

    Fuerschbach, Phillip W. (Tijeras, NM); Jellison, James L. (Albuquerque, NM); Keicher, David M. (Albuquerque, NM); Oberkampf, William L. (Albuquerque, NM)

    1991-01-01

    A method and apparatus for enhancing the weldment of a laser welding system is provided. The laser weld plume control device includes a cylindrical body defining an upside-down cone cavity; the upper surface of the body circumscribes the base of the cone cavity, and the vertex of the cone cavity forms an orifice concentrically located with respect to the laser beam and the plume which forms as a result of the welding operation. According to the method of the invention, gas is directed radially inward through inlets in the upper surface of the body into and through channels in the wall of the body and finally through the orifice of the body, and downward onto the surface of the weldment. The gas flow is then converted by the orifice of the device from radial flow to an axisymmetric gas jet flowing away from the weldment surface in a direction perpendicular to the surface and opposite to that of the laser.

  4. 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.

  5. Eddy Current Examination of Spent Nuclear Fuel Canister Closure Welds

    SciTech Connect (OSTI)

    Arthur D. Watkins; Dennis C. Kunerth; Timothy R. McJunkin

    2006-04-01

    The National Spent Nuclear Fuel Program (NSNFP) has developed standardized DOE SNF canisters for handling and interim storage of SNF at various DOE sites as well as SNF transport to and SNF handling and disposal at the repository. The final closure weld of the canister will be produced remotely in a hot cell after loading and must meet American Society of Mechanical Engineers (ASME) Section III, Division 3 code requirements thereby requiring volumetric and surface nondestructive evaluation to verify integrity. This paper discusses the use of eddy current testing (ET) to perform surface examination of the completed welds and repair cavities. Descriptions of integrated remote welding/inspection system and how the equipment is intended function will also be discussed.

  6. 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.

  7. 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

  8. Development of a Fiber Laser Welding Capability for the W76, MC4702 Firing Set

    SciTech Connect (OSTI)

    Samayoa, Jose

    2010-05-12

    Development work to implement a new welding system for a Firing Set is presented. The new system is significant because it represents the first use of fiber laser welding technology at the KCP. The work used Six-Sigma tools for weld characterization and to define process performance. Determinations of workable weld parameters and comparison to existing equipment were completed. Replication of existing waveforms was done utilizing an Arbitrary Pulse Generator (APG), which was used to modulate the fiber laser’s exclusive continuous wave (CW) output. Fiber laser weld process capability for a Firing Set is demonstrated.

  9. Detecting Weld Zone Over Anticorrosion Painting by Rotating Uniform Eddy Current Probe

    SciTech Connect (OSTI)

    Hoshikawa, H.; Koyama, K.; Naruse, Y. [Nihon University, Izumicho Narashino Chiba 275-8575 (Japan)

    2005-04-09

    The authors have studied application of rotating uniform eddy current probe to detecting weld zone in steed material over anticorrosion painting. The probe detects not only weld position by the signal level but also weld direction by the signal phase. The experimental results have indicated that the probe provides a signal almost linear to its position with respect to weld zone center over the full width of weld. The signal of the probe is much less influenced by the painting thickness variation than that of the conventional differential pancake-coils probe.

  10. Apparatus and process for ultrasonic seam welding stainless steel foils

    DOE Patents [OSTI]

    Leigh, Richard W. (New York, NY)

    1992-01-01

    An ultrasonic seam welding apparatus having a head which is rotated to form contact, preferably rolling contact, between a metallurgically inert coated surface of the head and an outside foil of a plurality of layered foils or work materials. The head is vibrated at an ultrasonic frequency, preferably along a longitudinal axis of the head. The head is constructed to transmit vibration through a contacting surface of the head into each of the layered foils. The contacting surface of the head is preferably coated with aluminum oxide to prevent the head from becoming welded to layered stainless steel foils.

  11. FRICTION STIR SPOT WELDING OF 6016 ALUMINUM ALLOY

    SciTech Connect (OSTI)

    Mishra, Rajiv S.; Webb, S.; Freeney, T. A.; Chen, Y. L.; Gayden, X.; Grant, Glenn J.; Herling, Darrell R.

    2007-01-08

    Friction stir spot welding (FSSW) of 6016 aluminum alloy was evaluated with conventional pin tool and new off-center feature tools. The off-center feature tool provides significant control over the joint area. The tool rotation rate was varied between 1000 and 2500 rpm. Maximum failure strength was observed in the tool rotation range of 1200-1500 rpm. The results are interpreted in the context of material flow in the joint and influence of thermal input on microstructural changes. The off-center feature tool concept opens up new possibilities for plunge-type friction stir spot welding.

  12. INVESTIGATION OF THE POTENTIAL FOR CAUSTIC STRESS CORROSION CRACKING OF A537 CARBON STEEL NUCLEAR WASTE TANKS

    SciTech Connect (OSTI)

    Lam, P.

    2009-10-15

    The evaporator recycle streams contain waste in a chemistry and temperature regime that may be outside of the current waste tank corrosion control program, which imposes temperature limits to mitigate caustic stress corrosion cracking (CSCC). A review of the recent service history (1998-2008) of Tanks 30 and 32 showed that these tanks were operated in highly concentrated hydroxide solution at high temperature. Visual inspections, experimental testing, and a review of the tank service history have shown that CSCC has occurred in uncooled/un-stress relieved F-Area tanks. Therefore, for the Type III/IIIA waste tanks the efficacy of the stress relief of welding residual stress is the only corrosion-limiting mechanism. The objective of this experimental program is to test carbon steel small scale welded U-bend specimens and large welded plates (12 x 12 x 1 in.) in a caustic solution with upper bound chemistry (12 M hydroxide and 1 M each of nitrate, nitrite, and aluminate) and temperature (125 C). These conditions simulate worst-case situations in Tanks 30 and 32. Both as-welded and stress-relieved specimens have been tested. No evidence of stress corrosion cracking was found in the U-bend specimens after 21 days of testing. The large plate test is currently in progress, but no cracking has been observed after 9 weeks of immersion. Based on the preliminary results, it appears that the environmental conditions of the tests are unable to develop stress corrosion cracking within the duration of these tests.

  13. Case1: Outlet of the pipe without a bend and a weld Case2: Outlet of the pipe with 90/90 bend and 30 weld

    E-Print Network [OSTI]

    McDonald, Kirk

    1 #12;Case1: Outlet of the pipe without a bend and a weld Case2: Outlet of the pipe with 90°/90° bend and 30° weld 2 #12;3 Y X Z symmetry Velocity Inlet Wall Pressure Outlet Wall Normalized by Djet inlet from pipeflow study with a 30° weld out of bend plan, and with a 90°/90° bend. Mesh: 15M. #12;Hg

  14. Coiled tubing: Early warning system to detect flaws in flat sheet prior to rolling and welding

    SciTech Connect (OSTI)

    Edens, C.W. )

    1994-05-01

    Through experimentation and dynamic evaluation of skelp at a coiled tubing mill, the use of leakage flux solid state sensing devices shows clearly that the requirement for nondestructively testing skelp can be met. As coiled tubing for drilling purposes gains wider usage, its skelp can take advantage of upstream inspection prior to forming the tubes. A reliable coiled tubing product is one in which every aspect of its manufacturing was considered, from raw material through final inspection. In no other way can the concept of total quality management be satisfied providing reliability of product use. A guarantee of fitness for purpose falls directly on the coiled tubing manufacturer. Purveyors of jointed electronic resistance weld tubulars may also take advantage of this inspection method. The American Petroleum Institute (API) has recently established a committee to study and formulate recommended practices for coiled tubing operations.

  15. Prenatal maternal stress programs infant stress regulation.

    E-Print Network [OSTI]

    Davis, Elysia Poggi; Glynn, Laura M; Waffarn, Feizal; Sandman, Curt A

    2011-01-01

    restraint stress on the hypothalamus-pituitary- adrenal axisnucleus of the hypothalamus, hippocampus, and amygdala (

  16. Effects of Prenatal Stress on Insulin Sensitivity, Physiological Stress Responses, Growth, and Temperament of Brahman Calves 

    E-Print Network [OSTI]

    Schmidt, Sarah Erin

    2014-04-24

    Stress incurred due to standard management practices applied to pregnant cattle may affect the health and productivity of the offspring. Separate studies were conducted to determine: 1) the extent to which transportation ...

  17. Carbon Diffusion Across Dissimilar Steel Welds

    E-Print Network [OSTI]

    Race, Julia Margaret

    1992-12-08

    generation plant is illustrated in Figure 1.1. Furnace walls Superheater Reheater Turbine Condenser Economiser Figure 1.1: Schematic representation of the power plant layout. 1.2 Material considerations 1.2.1 111echanical properties The first requirement... to sustain steady, instantaneous or cyclic stresses when operating at the design temperature and pressure. Fossil fuelled boilers and gas and liquid metal cooled reactors can generate steam at upto 600°C, but more recently temperatures have been standardised...

  18. Phase transformations in welded supermartensitic stainless steels

    E-Print Network [OSTI]

    Carrouge, Dominique

    steels, show a marked temperature dependence of the fracture toughness, as indicated in figure 1.11. At high temperatures fracture occurs normally by ductile rupture, whereas cleavage is the dominating fracture mode at low temperatures. The low carbon con... ductile metal experiences brittle frac- ture when exposed to both a tensile stress and hydrogen resulting from metal dissolu- tion in a corrosive atmosphere. Hydrogen-induced cracks are most often transgranu- lar, although intergranular fracture...

  19. Numerical simulation of linear fiction welding (LFW) processes

    SciTech Connect (OSTI)

    Fratini, L.; La Spisa, D. [University of Palermo-Dept. of Industrial engineering (Italy)

    2011-05-04

    Solid state welding processes are becoming increasingly important due to a large number of advantages related to joining ''unweldable'' materials and in particular light weight alloys. Linear friction welding (LFW) has been used successfully to bond non-axisymmetric components of a range of materials including titanium alloys, steels, aluminum alloys, nickel, copper, and also dissimilar material combinations. The technique is useful in the research of quality of the joints and in reducing costs of components and parts of the aeronautic and automotive industries.LFW involves parts to be welded through the relative reciprocating motion of two components under an axial force. In such process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and proper bonding conditions due to both the temperature increase and the local pressure of the two edges to be welded. This paper is a comparative test between the numerical model in two dimensions, i.e. in plane strain conditions, and in three dimensions of a LFW process of AISI1045 steel specimens. It must be observed that the 3D model assures a faithful simulation of the actual threedimensional material flow, even if the two-dimensional simulation computational times are very short, a few hours instead of several ones as the 3D model. The obtained results were compared with experimental values found out in the scientific literature.

  20. Friction Stir Welding of Lightweight Vehicle Structures: Final Report

    SciTech Connect (OSTI)

    Sanella, M L

    2008-08-31

    The purpose of this Cooperative Research and Development Agreement (CRADA) between UTBattelle, LLC and Ford Motor Company was to establish friction stir welding (FSW) and friction stir processing as viable options for use in construction of lightweight substructures for trucks and cars, including engine cradles, suspension sub frames, instrument panel supports, and intake manifolds.

  1. WELDING RESEARCH JUNE 2007, VOL. 86-s170

    E-Print Network [OSTI]

    DuPont, John N.

    being considered as corrosion-resistant coatings for boiler tubes in coal-fired power plants. Although cladding. The presence of (Fe,Cr)xCy and (Fe,Al)3C type carbides was found to im- prove the cracking variety of low NOx-type atmospheres (Refs. 1, 2). Un- fortunately, work to date has shown that weld

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

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Lithium-Assisted Electrochemical Welding in Silicon Nanowire Battery Electrodes Khim Karki, Eric-healing, interfacial lithium diffusivity, in situ TEM, lithium-ion battery Silicon is an auspicious candidate to replace today's widely utilized graphitic anodes in lithium ion batteries because its specific energy

  3. Stainless Steel 18-10 CO2 Laser Welding And Plasma Diagnostics

    SciTech Connect (OSTI)

    Amar, Taibi [Department of Mechanical Engineering, University of M'sila (Algeria); Laboratory of Industrial Physics, Thermal centre of INSA of Lyon, CETHIL (France); Michel, Laurent [Laboratory of Industrial Physics, Thermal centre of INSA of Lyon, CETHIL (France)

    2008-09-23

    The welding of materials by CO2 laser took significant considerations in industry, for the reason of the quality of the carried out weldings, and for other many advantages, but the automation of the welding operation requires a control system in real time. The operation of welding is an operation of interaction between the radiation (laser), and the matter (welded part), which is characterized by the vaporization of the matter, formation of the keyhole in material, and appearance of plasma over the material. This study relates to the relation between the welding (molten material) and the plasma which is formed on material. The light emitted by plasma during laser welding was recorded by an OMA detector (Optical Multichannel Analyzer) over a wavelength width of 450 A ring . The analysis of this light allows to determine the composition of this plasma, its dimensions, and the state of its energy according to the laser parameters. The welded material is the stainless steel 18-10, it was found that the intensity of the light emitted by plasma depends on laser power, the welding speed, the flow rate of assist gas. The relation between the plasma and the state of the bead were analyzed for on-line monitoring welding.

  4. Simulation of Distortion and Residual Stress Development During Heat Treatment of Steel Castings

    SciTech Connect (OSTI)

    Christoph Beckermann; Kent Carlson

    2011-07-22

    Heat treatment and associated processing, such as quenching, are critical during high strength steel casting production. These processes must be managed closely to prevent thermal and residual stresses that may result in distortion, cracking (particularly after machining), re-work, and weld repair. The risk of casting distortion limits aggressive quenching that can be beneficial to the process and yield an improved outcome. As a result of these distortions, adjustments must be made to the casting or pattern design, or tie bars must be added. Straightening castings after heat treatments can be both time-consuming and expensive. Residual stresses may reduce a casting���¢��������s overall service performance, possibly resulting in catastrophic failure. Stress relieving may help, but expends additional energy in the process. Casting software is very limited in predicting distortions during heat treatment, so corrective measures most often involve a tedious trial-and-error procedure. An extensive review of existing heat treatment residual stress and distortion modeling revealed that it is vital to predict the phase transformations and microstructure of the steel along with the thermal stress development during heat treatment. After reviewing the state-of-the-art in heat treatment residual stress and distortion modeling, an existing commercial code was selected because of its advanced capabilities in predicting phase transformations, the evolving microstructure and related properties along with thermal stress development during heat treatment. However, this software was developed for small parts created from forgings or machined stock, and not for steel castings. Therefore, its predictive capabilities for heat treatment of steel castings were investigated. Available experimental steel casting heat treatment data was determined to be of insufficient detail and breadth, and so new heat treatment experiments were designed and performed, casting and heat treating modified versions of the Navy-C ring (a classical test shape for heat treatment experiments) for several carbon and low alloy steels in order to generate data necessary to validate the code. The predicted distortions were in reasonable agreement with the experimentally measured values. However, the final distortions in the castings were small, making it difficult to determine how accurate the predictions truly are. It is recommended that further validation of the software be performed with the aid of additional experiments with large production steel castings that experience significant heat treatment distortions. It is apparent from this research that the mechanical properties of the bonded sand used for cores and sand molds are key in producing accurate stress simulation results. Because of this, experiments were performed to determine the temperature-dependent elastic modulus of a resin-bonded sand commonly utilized in the steel casting industry. The elastic modulus was seen to vary significantly with heating and cooling rates. Also, the retained room temperature elastic modulus after heating was seen to degrade significantly when the sand was heated above 125�������°C. The elastic modulus curves developed in this work can readily be utilized in casting simulation software. Additional experiments with higher heating rates are recommended to determine the behavior of the elastic modulus in the sand close to the mold-metal interface. The commercial heat treatment residual stress and distortion code, once fully validated, is expected to result in an estimated energy savings of 2.15 trillion BTU���¢��������s/year. Along with these energy savings, reduction of scrap and improvement in casting yield will result in a reduction of the environmental emissions associated with the melting and pouring of the metal which will be saved as a result of this technology.

  5. Slimhole and coiled tubing standards phase 1. Weld technology (January 1996). Final report, September 1994-December 1995

    SciTech Connect (OSTI)

    Newman, K.R.; Brown, P.; Van Arnam, D.

    1996-02-01

    The reliability and understanding of coiled tubing (CT) welds is an issue of concern in the oil and gas industry. Much work has been done to understand the fatigue characteristics of the base CT material. Until recently, little work had been done to understand the fatigue life of the CT welds, which are the weakest points in the CT string. A separate project funded by a joint industry group, recently performed a large number of fatigue tests on CT welds. This separate study showed significant room for improvement in the understanding of CT welds. The GRI-supported project attempts to improve the understanding of CT weld technology and methods by analyzing failed weld samples, reviewing and recommending new CT welding procedures and reviewing alternative welding techniques which could be use for CT welding.

  6. Slimhole and coiled tubing standards phase 1. Weld technology (February 1996). Final report, September 1994-December 1995

    SciTech Connect (OSTI)

    Newman, K.R.; Brown, P.; Van Arnam, D.

    1996-02-01

    The reliability and understanding of coiled tubing (CT) welds is an issue of concern in the oil and gas industry. Much work has been done to understand the fatigue characteristics of the base CT material. Until recently, little work had been done to understand the fatigue life of the CT welds, which are the weakest points in the CT string. A separate project funded by a joint industry group, recently performed a large number of fatigue tests on CT welds. This separate study showed significant room for improvement in the understanding of CT welds. The GRI-supported project attempts to improve the understanding of CT weld technology and methods by analyzing failed weld samples, reviewing and recommending new CT welding procedures and reviewing alternative welding techniques which could be use for CT welding.

  7. Final Report: A Transport Phenomena Based Approach to Probe Evolution of Weld Macro and Microstructures and A Smart Bi-directional Model of Fusion Welding

    SciTech Connect (OSTI)

    Dr. Tarasankar DebRoy

    2009-12-11

    In recent years, applications of numerical heat transfer and fluid flow models of fusion welding have resulted in improved understanding of both the welding processes and welded materials. They have been used to accurately calculate thermal cycles and fusion zone geometry in many cases. Here we report the following three major advancements from this project. First, we show how microstructures, grain size distribution and topology of welds of several important engineering alloys can be computed starting from better understanding of the fusion welding process through numerical heat transfer and fluid flow calculations. Second, we provide a conclusive proof that the reliability of numerical heat transfer and fluid flow calculations can be significantly improved by optimizing several uncertain model parameters. Third, we demonstrate how the numerical heat transfer and fluid flow models can be combined with a suitable global optimization program such as a genetic algorithm for the tailoring of weld attributes such as attaining a specified weld geometry or a weld thermal cycle. The results of the project have been published in many papers and a listing of these are included together with a list of the graduate thesis that resulted from this project. The work supported by the DOE award has resulted in several important national and international awards. A listing of these awards and the status of the graduate students are also presented in this report.

  8. 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.

  9. A REVIEW OF THE DEVELOPMENT OF FERRITIC CONSUMABLES FOR THE WELDING OF 9percent NICKEL STEEL: RESEARCH IN THE U. S. AND JAPAN.

    E-Print Network [OSTI]

    Mahin, K.W.

    2013-01-01

    Lovv Conta·inment Plant, Welding Institute, London, Paperon Weldin t inment Plant, Welding Institute, London, Paper .Ferritic Filler l~etal Welding of 9% Nickel Steel", To be

  10. On the development of nugget growth model for resistance spot welding

    SciTech Connect (OSTI)

    Zhou, Kang, E-mail: zhoukang326@126.com, E-mail: melcai@ust.hk; Cai, Lilong, E-mail: zhoukang326@126.com, E-mail: melcai@ust.hk [Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2014-04-28

    In this paper, we developed a general mathematical model to estimate the nugget growth process based on the heat energy delivered into the welds by the resistance spot welding. According to the principles of thermodynamics and heat transfer, and the effect of electrode force during the welding process, the shape of the nugget can be estimated. Then, a mathematical model between heat energy absorbed and nugget diameter can be obtained theoretically. It is shown in this paper that the nugget diameter can be precisely described by piecewise fractal polynomial functions. Experiments were conducted with different welding operation conditions, such as welding currents, workpiece thickness, and widths, to validate the model and the theoretical analysis. All the experiments confirmed that the proposed model can predict the nugget diameters with high accuracy based on the input heat energy to the welds.

  11. Pacific Northwest National Laboratory Investigation of the Stress Corrosion Cracking in Nickel-Base Alloys, Volume 2

    SciTech Connect (OSTI)

    Bruemmer, Stephen M.; Toloczko, Mychailo B.; Olszta, Matthew J.

    2012-03-01

    The objective of this program is to evaluate the primary water stress corrosion cracking (PWSCC) susceptibility of high chromium alloy 690 and its weld metals, establish quantitative measurements of crack-growth rates and determine relationships among cracking susceptibility, environmental conditions and metallurgical characteristics. Stress-corrosion, crack-growth rates have been determined for 12 alloy 690 specimens, 11 alloy 152/52/52M weld metal specimens, 4 alloy 52M/182 overlay specimens and 2 alloy 52M/82 inlay specimens in simulated PWR primary water environments. The alloy 690 test materials included three different heats of extruded control-rod-drive mechanism (CRDM) tubing with variations in the initial material condition and degree of cold work for one heat. Two cold-rolled (CR) alloy 690 plate heats were also obtained and evaluated enabling comparisons to the CR CRDM materials. Weld metal, overlay and inlay specimens were machined from industry mock ups to provide plant-representative materials for testing. Specimens have been tested for one alloy 152 weld, two alloy 52 welds and three alloy 52M welds. The overlay and inlay specimens were prepared to propagate stress-corrosion cracks from the alloy 182 or 82 material into the more resistant alloy 52M. In all cases, crack extension was monitored in situ by direct current potential drop (DCPD) with length resolution of about +1 µm making it possible to measure extremely low growth rates approaching 5x10-10 mm/s. Most SCC tests were performed at 325-360°C with hydrogen concentrations from 11-29 cc/kg; however, environmental conditions were modified during a few experiments to evaluate the influence of temperature, water chemistry or electrochemical potential on propagation rates. In addition, low-temperature (~50°C) cracking behavior was examined for selected alloy 690 and weld metal specimens. Extensive characterizations have been performed on material microstructures and stress-corrosion cracks by optical and electron microscopy techniques and linked to crack-growth test results to help define material and environmental parameters controlling SCC susceptibility.

  12. Sample preparation method for glass welding by ultrashort laser pulses yields higher seam strength

    SciTech Connect (OSTI)

    Cvecek, K.; Miyamoto, I.; Strauss, J.; Wolf, M.; Frick, T.; Schmidt, M.

    2011-05-01

    Glass welding by ultrashort laser pulses allows joining without the need of an absorber or a preheating and postheating process. However, cracks generated during the welding process substantially impair the joining strength of the welding seams. In this paper a sample preparation method is described that prevents the formation of cracks. The measured joining strength of samples prepared by this method is substantially higher than previously reported values.

  13. 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

  14. Management Overview

    Energy Savers [EERE]

    so only a half cross-section of the set-up is shown The test tube is 12mmOD with 1 mm thick walls and 50 mm long 1000 psi internal applied pressure 950C Welds...

  15. HEAT INPUT AND POST WELD HEAT TREATMENT EFFECTS ON REDUCED-ACTIVATION...

    Office of Scientific and Technical Information (OSTI)

    years because of their improved irradiation resistance. However, they can suffer from welding induced property degradations. In this paper, a solid phase joining technology...

  16. Stability of Y Ti O Precipitates in Friction Stir Welded Nanostructure...

    Office of Scientific and Technical Information (OSTI)

    promising materials for fuel cladding and structural applications in the next generation nuclear reactor. This study evaluates microstructure of friction stir welded NFA using...

  17. 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...

  18. 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.

  19. Welding/sealing glass-enclosed space in a vacuum

    DOE Patents [OSTI]

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

    1996-02-06

    A method of welding and sealing the edges of two juxtaposed glass sheets together to seal a vacuum space between the sheets comprises the steps of positioning a radiation absorbent material, such as FeO, VO{sub 2}, or NiO, between the radiation transmissive glass sheets adjacent the edges and then irradiating the absorbent material, preferably with a laser beam, through at least one of the glass sheets. Heat produced by the absorbed radiation in the absorbent material melts glass in the portions of both glass sheets that are adjacent the absorbent material, and the melted glass from both sheets flows together to create the weld when the melted glass cools and hardens. The absorbent material can be dissolved and diffused into the melted glass to the extent that it no longer absorbs enough energy to keep the glass melted, thus, with appropriate proportioning of absorbent material to source energy power and welding heat needed, the process can be made self-stopping. 8 figs.

  20. Welding/sealing glass-enclosed space in a vacuum

    DOE Patents [OSTI]

    Tracy, C. Edwin (Golden, CO); Benson, David K. (Golden, CO)

    1996-01-01

    A method of welding and sealing the edges of two juxtaposed glass sheets together to seal a vacuum space between the sheets comprises the steps of positioning a radiation absorbant material, such as FeO, VO.sub.2, or NiO, between the radiation transmissive glass sheets adjacent the edges and then irradiating the absorbant material, preferably with a laser beam, through at least one of the glass sheets. Heat produced by the absorbed radiation in the absorbant material melts glass in the portions of both glass sheets that are adjacent the absorbant material, and the melted glass from both sheets flows together to create the weld when the melted glass cools and hardens. The absorbant material can be dissolved and diffused into the melted glass to the extent that it no longer absorbs enough energy to keep the glass melted, thus, with appropriate proportioning of absorbant material to source energy power and welding heat needed, the process can be made self-stopping.

  1. Further Development at JET of Remote Digital Photogrammetry Techniques and Remote Welding Under Conditions of Restricted Access

    E-Print Network [OSTI]

    Further Development at JET of Remote Digital Photogrammetry Techniques and Remote Welding Under Conditions of Restricted Access

  2. Effect of Composition on the Formation of Sigma during Single-Pass Welding of Mo-Bearing Stainless Steels

    E-Print Network [OSTI]

    DuPont, John N.

    Effect of Composition on the Formation of Sigma during Single-Pass Welding of Mo-Bearing Stainless, and laser welds were prepared on each alloy at constant power and travel speeds ranging from 4.2 to 42 mm d-ferrite alloys. The high cooling rates in the laser welds (estimated to range from 104 °C/s to 105

  3. Proceedings of Sino-Swedish Structural Materials Symposium 2007 Effect of Welding Heat Input on Simulated HAZ

    E-Print Network [OSTI]

    Hong, Soon Hyung

    Proceedings of Sino-Swedish Structural Materials Symposium 2007 Effect of Welding Heat Input Institute, Beijing 100081,China) Abstract: This study investigates the correlation among the welding heat that a relatively low energy input is recommended for welding of low carbon V-N microalloyed steel, according

  4. Development of a Robust and Cost-Effective Friction Stir Welding Process for Use in Advanced Military Vehicles

    E-Print Network [OSTI]

    Grujicic, Mica

    Development of a Robust and Cost-Effective Friction Stir Welding Process for Use in Advanced potential). Unfortu- nately, these alloys are not very amenable to conventional fusion-based welding technologies and in-order to obtain high-quality welds, solid-state joining technologies such as Friction stir

  5. Prenatal maternal stress programs infant stress regulation.

    E-Print Network [OSTI]

    Davis, Elysia Poggi; Glynn, Laura M; Waffarn, Feizal; Sandman, Curt A

    2011-01-01

    Programs Infant Stress Regulation Elysia Poggi Davis, PhDglucocorticoids disrupts the regulation of physiological andstress alters circadian regulation and laboratory levels of

  6. Contstraint effects of shallow cracks in structures containing fillet weld toe cracks 

    E-Print Network [OSTI]

    Neligon, Melinda T

    1995-01-01

    for structures containing a/W--O.l and a/W--O.5 fillet weld toe cracks. The Anderson-Dodds scaling model is applied to quantify the effects of finite size on J contour integral values for structures containing a/W=O.l and a/W=0.5 fillet weld toe cracks loaded...

  7. Joint strength in high speed friction stir spot welded DP 980 steel

    SciTech Connect (OSTI)

    Saunders, Nathan; Miles, Michael; Hartman, Trent; Hovanski, Yuri; Hong, Sung Tae; Steel, Russell

    2014-05-01

    High speed friction stir spot welding was applied to 1.2 mm thick DP 980 steel sheets under different welding conditions, using PCBN tools. The range of vertical feed rates used during welding was 2.5 mm – 102 mm per minute, while the range of spindle speeds was 2500 – 6000 rpm. Extended testing was carried out for five different sets of welding conditions, until tool failure. These welding conditions resulted in vertical welding loads of 3.6 – 8.2 kN and lap shear tension failure loads of 8.9 – 11.1 kN. PCBN tools were shown, in the best case, to provide lap shear tension fracture loads at or above 9 kN for 900 spot welds, after which tool failure caused a rapid drop in joint strength. Joint strength was shown to be strongly correlated to bond area, which was measured from weld cross sections. Failure modes of the tested joints were a function of bond area and softening that occurred in the heat-affected zone.

  8. 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

  9. Linear Friction Welding Process Model for Carpenter Custom 465 Precipitation-Hardened Martensitic

    E-Print Network [OSTI]

    Grujicic, Mica

    for Carpenter Custom 465 precipitation-hardened martensitic stainless steel to develop a linear friction weldingLinear Friction Welding Process Model for Carpenter Custom 465 Precipitation-Hardened Martensitic Stainless Steel M. Grujicic, R. Yavari, J.S. Snipes, S. Ramaswami, C.-F. Yen, and B.A. Cheeseman (Submitted

  10. ULTIMATE BEHAVIOR OF HEAVY STEEL SECTION WELDED SPLICES AND DESIGN IMPLICATIONS

    E-Print Network [OSTI]

    Bruneau, Michel

    ULTIMATE BEHAVIOR OF HEAVY STEEL SECTION WELDED SPLICES AND DESIGN IMPLICATIONS By Michel Bruneau are tested. Test specimens are devised so splices are located in regions of pure bending. The partial) specifies special Charpy V-notch testing re- quirements, along with some other weld-preparation requirements

  11. 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.

  12. BRIDGE NUMBERS FOR VIRTUAL AND WELDED KNOTS HANS U. BODEN AND ANNE ISABEL GAUDREAU

    E-Print Network [OSTI]

    Boden, Hans U.

    BRIDGE NUMBERS FOR VIRTUAL AND WELDED KNOTS HANS U. BODEN AND ANNE ISABEL GAUDREAU Abstract. Using Gauss diagrams, one can define the virtual bridge number vb(K) and the welded bridge number wb and Manturov showed that vb(K) = br(K), the bridge number as a classical knot, and we ask whether the same

  13. 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.

  14. The Size of the Sensitization Zone in 304 Stainless Steel Welds

    E-Print Network [OSTI]

    Eagar, Thomas W.

    ) ) viS i tf. f. t ~ I~ i \\ ! l The Size of the Sensitization Zone in 304 Stainless Steel Welds N stainless steel welds have been studied through a swtistical/y desigm·d experimellt. Tire resuits indicate stainless steel plates using argon shielding gas. The chemical com- position of the stainless steel is given

  15. 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.

  16. 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.

  17. 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.

  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. Stress, performance, and control room operations

    SciTech Connect (OSTI)

    Fontaine, C.W.

    1990-01-01

    The notion of control room operator performance being detrimentally affected by stress has long been the focus of considerable conjecture. It is important to gain a better understanding of the validity of this concern for the development of effective severe-accident management approaches. This paper illustrates the undeniable negative impact of stress on a wide variety of tasks. A computer-controlled simulated work environment was designed in which both male and female operators were closely monitored during the course of the study for both stress level (using the excretion of the urine catecholamines epinephrine and norepinephrine as an index) and job performance. The experimental parameters employed by the study when coupled with the subsequent statistical analyses of the results allow one to make some rather striking comments with respect to how a given operator might respond to a situation that he or she perceives to be psychologically stressful (whether the stress be externally or internally generated). The findings of this study clearly indicated that stress does impact operator performance on tasks similar in nature to those conducted by control room operators and hence should be seriously considered in the development of severe-accident management strategies.

  20. 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.

  1. Upgrade of laser and electron beam welding database

    E-Print Network [OSTI]

    Furman, Magdalena

    2014-01-01

    The main purpose of this project was to fix existing issues and update the existing database holding parameters of laser-beam and electron-beam welding machines. Moreover, the database had to be extended to hold the data for the new machines that arrived recently at the workshop. As a solution - the database had to be migrated to Oracle framework, the new user interface (using APEX) had to be designed and implemented with the integration with the CERN web services (EDMS, Phonebook, JMT, CDD and EDH).

  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. 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.

  4. 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.

  5. Beam/seam alignment control for electron beam welding

    DOE Patents [OSTI]

    Burkhardt, Jr., James H. (Knoxville, TN); Henry, J. James (Oak Ridge, TN); Davenport, Clyde M. (Knoxville, TN)

    1980-01-01

    This invention relates to a dynamic beam/seam alignment control system for electron beam welds utilizing video apparatus. The system includes automatic control of workpiece illumination, near infrared illumination of the workpiece to limit the range of illumination and camera sensitivity adjustment, curve fitting of seam position data to obtain an accurate measure of beam/seam alignment, and automatic beam detection and calculation of the threshold beam level from the peak beam level of the preceding video line to locate the beam or seam edges.

  6. Weld County, Colorado: Energy Resources | 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 JEnvironmental Jump to:EA EISTJThinWarsaw, Poland:EnergyWe Energy Wind FarmWege WindWeld County,

  7. Peritraumatic Interventions for Stress Resilience

    E-Print Network [OSTI]

    Plumb, Traci Nicole

    2015-01-01

    deficits following traumatic stress. Annual Meeting for theT.N. (2015). Paths to stress resilience. Invited Colloquium.Neurobiology of Post- Traumatic Stress Disorder, New York:

  8. 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

  9. Network Management Network Management

    E-Print Network [OSTI]

    Giaccone, Paolo

    Network Management Pag. 1 Network Management Network management and QoS provisioning - 1Andrea of this license visit: http://creativecommons.org/licenses/by-nc- /3 0/ Network management and QoS provisioning ­ Chapter 9, Network Management, of the book Jim Kurose, Keith Ross, Computer Networking, A Top Down

  10. Management Plan Management Plan

    E-Print Network [OSTI]

    Management Plan Management Plan "Management and restoration programs for native salmonids have communities" J. Lichatowich et al. 1998. A Conceptual Foundation for the Management of Native Salmonids in the Deschutes River. The Management Plan consists of five elements described in the Council's program: 1

  11. 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.

  12. Leak-Tight Welding Experience from the Industrial Assembly of the LHC Cryostats at CERN

    E-Print Network [OSTI]

    Bourcey, N; Chiggiato, P; Limon, P; Mongelluzzo, A; Musso, G; Poncet, A; Parma, V

    2008-01-01

    The assembly of the approximately 1700 LHC main ring cryostats at CERN involved extensive welding of cryogenic lines and vacuum vessels. More than 6 km of welding requiring leak tightness to a rate better than 1.10-9 mbar.l.s-1 on stainless steel and aluminium piping and envelopes was made, essentially by manual welding but also making use of orbital welding machines. In order to fulfil the safety regulations related to pressure vessels and to comply with the leak-tightness requirements of the vacuum systems of the machine, welds were executed according to high qualification standards and following a severe quality assurance plan. Leak detection by He mass spectrometry was extensively used. Neon leak detection was used successfully to locate leaks in the presence of helium backgrounds. This paper presents the quality assurance strategy adopted for welds and leak detection. It presents the statistics of non-conformities on welds and leaks detected throughout the entire production and the advances in the use...

  13. Friction Stir Spot Welding (FSSW) of Advanced High Strength Steel (AHSS)

    SciTech Connect (OSTI)

    Santella, M. L.; Hovanski, Yuri; Pan, Tsung-Yu

    2012-04-16

    Friction stir spot welding (FSSW) is applied to join advanced high strength steels (AHSS): galvannealed dual phase 780 MPa steel (DP780GA), transformation induced plasticity 780 MPa steel (TRIP780), and hot-stamped boron steel (HSBS). A low-cost Si3N4 ceramic tool was developed and used for making welds in this study instead of polycrystalline cubic boron nitride (PCBN) material used in earlier studies. FSSW has the advantages of solid-state, low-temperature process, and the ability of joining dissimilar grade of steels and thicknesses. Two different tool shoulder geometries, concave with smooth surface and convex with spiral pattern, were used in the study. Welds were made by a 2-step displacement control process with weld time of 4, 6, and 10 seconds. Static tensile lap-shear strength achieved 16.4 kN for DP780GA-HSBS and 13.2kN for TRIP780-HSBS, above the spot weld strength requirements by AWS. Nugget pull-out was the failure mode of the joint. The joining mechanism was illustrated from the cross-section micrographs. Microhardness measurement showed hardening in the upper sheet steel (DP780GA or TRIP780) in the weld, but softening of HSBS in the heat-affect zone (HAZ). The study demonstrated the feasibility of making high-strength AHSS spot welds with low-cost tools.

  14. Multiple pass and multiple layer friction stir welding and material enhancement processes

    DOE Patents [OSTI]

    Feng, Zhili (Knoxville, TN) [Knoxville, TN; David, Stan A. (Knoxville, TN) [Knoxville, TN; Frederick, David Alan (Harriman, TN) [Harriman, TN

    2010-07-27

    Processes for friction stir welding, typically for comparatively thick plate materials using multiple passes and multiple layers of a friction stir welding tool. In some embodiments a first portion of a fabrication preform and a second portion of the fabrication preform are placed adjacent to each other to form a joint, and there may be a groove adjacent the joint. The joint is welded and then, where a groove exists, a filler may be disposed in the groove, and the seams between the filler and the first and second portions of the fabrication preform may be friction stir welded. In some embodiments two portions of a fabrication preform are abutted to form a joint, where the joint may, for example, be a lap joint, a bevel joint or a butt joint. In some embodiments a plurality of passes of a friction stir welding tool may be used, with some passes welding from one side of a fabrication preform and other passes welding from the other side of the fabrication preform.

  15. 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.

  16. Evaluation of Internal Brushing on Pinch Weld Quality

    SciTech Connect (OSTI)

    Korinko, P

    2005-12-01

    Post machining operations such as borescope inspection can cause linear indications down the length of the bore of fill stems. Often these indications are removed or obscured using rotary wire brushing. This study evaluated the effect this mechanical operation may have on pinch weld quality when relatively cold welds were made. A total of four stems with two levels of brushing of both Type 304L and 21-6-9 stainless steels were tested. In addition, two each of the Type 304L stems were Nitradd cleaned and the other two were aqueously cleaned; all four 21-6-9 stems were aqueously cleaned. All of the brushed stem areas exhibited more surface anomalies based on borescope evaluation. On average, the bond rating was a higher value (worse) for the brushed areas than the unadulterated areas for both Type 304L and 21-6-9 stems. The test method used may have biased the results towards a lesser quality bond for the brushed areas so additional testing is recommended.

  17. 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.

  18. Process of welding gamma prime-strengthened nickel-base superalloys

    DOE Patents [OSTI]

    Speigel, Lyle B.; White, Raymond Alan; Murphy, John Thomas; Nowak, Daniel Anthony

    2003-11-25

    A process for welding superalloys, and particularly articles formed of gamma prime-strengthened nickel-base superalloys whose chemistries and/or microstructures differ. The process entails forming the faying surface of at least one of the articles to have a cladding layer of a filler material. The filler material may have a composition that is different from both of the articles, or the same as one of the articles. The cladding layer is machined to promote mating of the faying surfaces, after which the faying surfaces are mated and the articles welded together. After cooling, the welded assembly is free of thermally-induced cracks.

  19. Porosity in millimeter-scale welds of stainless steel : three-dimensional characterization.

    SciTech Connect (OSTI)

    Aagesen, Larry K.; Madison, Jonathan D.

    2012-05-01

    A variety of edge joints utilizing a continuous wave Nd:YAG laser have been produced and examined in a 304-L stainless steel to advance fundamental understanding of the linkage between processing and resultant microstructure in high-rate solidification events. Acquisition of three-dimensional reconstructions via micro-computed tomography combined with traditional metallography has allowed for qualitative and quantitative characterization of weld joints in a material system of wide use and broad applicability. The presence, variability and distribution of porosity, has been examined for average values, spatial distributions and morphology and then related back to fundamental processing parameters such as weld speed, weld power and laser focal length.

  20. 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.

  1. FUNDAMENTAL STUDY OF MICRO-DEFECTS IN ELECTROPOLISHED EB-WELDED AND HYDROFORMED SRF ACCELERATING STRUCTURES

    SciTech Connect (OSTI)

    Sumption, Mike

    2014-08-29

    In the area of niobium elecroploshing fundamentals, we focused on undersanding the influence of the surface topology, and geometry (with effects from gravity included. The formation of a viscous film is essential for the electropolishing process to take place. The exact nature and composition of the film formed on niobium is still unknown because of its solubility in the electrolyte. Extensive pitting may take place at surface where a stable film cannot form. This has to be taken into consideration while determining the speed with which the SRF cavities are rotated while EP. Hydrodynamic aspects must be taken into consideration while optimizing the polishing parameters. There is improvement in surface finish with polishing time. There is a huge change in surface quality when the EP time is increased from 2 hours to 4 hours but not much change takes place when the time is further increased to 6 hours. So keeping the economic points in view, about 100 um defect layer removal may be sufficient to get the desired performance. In the area of Electropolishing of untreated and treated niobium with Weld Joints we studied untreated and treated Nb, especially for the heat affected areas next to welded bumps, electropolished for different durations. The electropolishing of the untreated Nb caused the formation of pits on the surface at about 15 min but they disappeared when the electropolishing duration was more than 15 min. Electropolishing for 120 min smoothened the surface of untreated Nb by levelling the surface, but the severe formation of pits on the whole surface was found after 240 min. The treatment of Nb significantly changed the Nb surface morphology which was covered by grains of different size that looked light or dark in the optical microscope. The treated Nb was susceptible to pitting during the entire electropolishing starting from 15 min and the dark grains had more susceptibility to pitting than the light grains. In addition, electropolishing for 240 min again resulted in severe pit formation. In the area of Bulge test and microstructure studies, we worked to create a useful constitutive relationship for the complex stress state that accompanies SRF cavity formation. To do so, bulge tests were performed on Cu and Nb tube samples that exhibited the greatest degrees of uniaxial elongation after HT. The data from the bulge tests and an accompanying set of tensile tests provided input to a finite-element model that recreated the bulge tests numerically. As expected the model based on the bulge test results fit the experimental data well at least at low stress levels safely below the bursting pressure. Not so for that based on the tensile results. The results of the study emphasize the importance of for bulge testing rather than tensile testing when deriving the constitutional relationships eventually needed for modelling the hydroforming of Nb SRF cavities.

  2. A 3-D mathematical model to identify organ-specific risks in rats during thermal stress

    E-Print Network [OSTI]

    outcomes associated with heat stress is critical for effective management and mitigation of injury, which in a rat exposed to heat stress in an attempt to understand the correlation between heat load core temperature measurements in control and heat-stressed rats and other published experimental data

  3. 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.

  4. 5) Management 5) Management

    E-Print Network [OSTI]

    Nowak, Robert S.

    5) Management c) Control #12;5) Management c) Control Prioritizing control ­ From Hiebert in Luken & Thieret (1997) · Types of information utilized Ecological impacts #12;5) Management c) Control impacts Economic impacts #12;5) Management c) Control Prioritizing control ­ From Hiebert in Luken

  5. Network Management Network Management

    E-Print Network [OSTI]

    Giaccone, Paolo

    Network Management Pag. 1 Network Management Andrea Bianco Telecommunication Network Group Network management and QoS provisioning - 1Andrea Bianco ­ TNG group - Politecnico di Torino Telecommunication management and QoS provisioning - 2Andrea Bianco ­ TNG group - Politecnico di Torino Stanford, California

  6. Manufacturing and Performance Assessment of Stamped, Laser Welded, and Nitrided FeCrV Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cells

    SciTech Connect (OSTI)

    Brady, Michael P; Abdelhamid, Mahmoud; Dadheech, G; Bradley, J; Toops, Todd J; Meyer III, Harry M; Tortorelli, Peter F

    2013-01-01

    A manufacturing and single-cell fuel cell performance study of stamped, laser welded, and gas nitrided ferritic stainless steel foils in an advanced automotive bipolar plate assembly design was performed. Two developmental foil compositions were studied: Fee20Cre4V and Fee23Cre4V wt.%. Foils 0.1 mm thick were stamped and then laser welded together to create single bipolar plate assemblies with cooling channels. The plates were then surface treated by pre-oxidation and nitridation in N2e4H2 based gas mixtures using either a conventional furnace or a short-cycle quartz lamp infrared heating system. Single-cell fuel cell testing was performed at 80 C for 500 h at 0.3 A/cm2 using 100% humidification and a 100%/40% humidification cycle that stresses the membrane and enhances release of the fluoride ion and promotes a more corrosive environment for the bipolar plates. Periodic high frequency resistance potential-current scans during the 500 h fuel cell test and posttest analysis of the membrane indicated no resistance increase of the plates and only trace levels of metal ion contamination.

  7. 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.

  8. Vehicle Technologies Office Merit Review 2014: On-Line Weld NDE with IR Thermography

    Broader source: Energy.gov [DOE]

    Presentation given by Oak Ridge National Laboratory at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about on-line weld...

  9. Vehicle Technologies Office Merit Review 2014: Collision Welding of Dissimilar Materials by Vaporizing Foil Actuator

    Office of Energy Efficiency and Renewable Energy (EERE)

    Presentation given by The Ohio State University at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about collision welding...

  10. 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.

  11. Vehicle Technologies Office Merit Review 2015: Collision Welding of Dissimilar Materials by Vaporizing Foil Actuator

    Broader source: Energy.gov [DOE]

    Presentation given by Ohio State University at 2015 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about collision welding of...

  12. 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.

  13. Cracked lifting lug welds on ten-ton UF{sub 6} cylinders

    SciTech Connect (OSTI)

    Dorning, R.E. [Martin Marietta Energy Systems, Inc., Piketon, OH (United States)

    1991-12-31

    Ten-ton, Type 48X, UF{sub 6} cylinders are used at the Portsmouth Gaseous Diffusion Plant to withdraw enriched uranium hexafluoride from the cascade, transfer enriched uranium hexafluoride to customer cylinders, and feed enriched product to the cascade. To accomplish these activities, the cylinders are lifted by cranes and straddle carriers which engage the cylinder lifting lugs. In August of 1988, weld cracks on two lifting lugs were discovered during preparation to lift a cylinder. The cylinder was rejected and tagged out, and an investigating committee formed to determine the cause of cracking and recommend remedial actions. Further investigation revealed the problem may be general to this class of cylinder in this use cycle. This paper discusses the actions taken at the Portsmouth site to deal with the cracked lifting lug weld problem. The actions include inspection activities, interim corrective actions, metallurgical evaluation of cracked welds, weld repairs, and current monitoring/inspection program.

  14. Specifying and testing weld neck flanges for better quality

    SciTech Connect (OSTI)

    Weirich, A.B. [Saudi Aramco, Dhahran (Saudi Arabia)

    1996-07-01

    Field failures and persistent defects have impelled users to demand improved reliability in weld neck flanges. This paper explains why and how to specify for better quality. The answers are straightforward: Specify clearly -- Quality begins with improved raw stock, is assured by good manufacturing practices, and is warranted by appropriate quality controls. Be reasonable, specifications must be commercially viable in today`s competitive environment. Inspect the merchandise: Quality cannot be assured without effective enforcement. To think otherwise is unrealistic, regardless how good the procurement specifications may be. Review purchasing policies: When suppliers of quality products are identified, restricted purchases should be instituted. Quicker deliveries and a reliable supply of good quality product are assured as manufacturers maintain upgraded inventories in anticipation of repeat business.

  15. 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.

  16. Eutectic structures in friction spot welding joint of aluminum alloy to copper

    SciTech Connect (OSTI)

    Shen, Junjun, E-mail: junjun.shen@hzg.de; Suhuddin, Uceu F. H.; Cardillo, Maria E. B.; Santos, Jorge F. dos [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Materials Mechanics, Solid-State Joining Processes, Max-Planck-Str. 1, 21502 Geesthacht (Germany)

    2014-05-12

    A dissimilar joint of AA5083 Al alloy and copper was produced by friction spot welding. The Al-MgCuAl{sub 2} eutectic in both coupled and divorced manners were found in the weld. At a relatively high temperature, mass transport of Cu due to plastic deformation, material flow, and atomic diffusion, combined with the alloy system of AA5083 are responsible for the ternary eutectic melting.

  17. Webinar January 12: Assessing Steel Pipeline and Weld Susceptibility to Hydrogen Embrittlement

    Broader source: Energy.gov [DOE]

    The Energy Department will present a live webinar titled "Assessing Steel Pipeline and Weld Susceptibility to Hydrogen Embrittlement” on Tuesday, January 12, from 12 to 1 p.m. EST. This webinar will discuss the breadth of testing performed at Sandia National Laboratories focused on the effects of hydrogen gas on steel pipelines and welds, and demonstrate how measured fatigue crack growth laws can be applied to calculate minimum wall thickness needed for steel hydrogen pipelines.

  18. Environment of deposition of the Permian Lyons Sandstone at Black Hollow Field, Weld County, Colorado 

    E-Print Network [OSTI]

    Frank, David Michael

    1984-01-01

    ENVIRONMENT OF DEPOSITION OF THE PERMIAN LYONS SANDSTONE AT BLACK HOLLOW FIELD, WELD COUNTY, COLORADO A Thesis by DAVID MICHAEL FRANK Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement... for the degree of MASTER QF SCIENCE August 1984 Major Subject: Geology ENVIRONMENT OF DEPOSITION OF THE PERMIAN LYONS SANDSTONE AT BLACK HOLLOW FIELD, WELD COUNTY, COLORADO A Thesis by DAVID MICHAEL FRANK Approved as to style and content by: R. R. Berg...

  19. The structure and properties of weld lines in injection molded thermoplastics 

    E-Print Network [OSTI]

    Manisali, Ali Ihsan

    1980-01-01

    THE STRUCTURE AND PROPERTIES OF WELD LINES IN INJECTION MOLDED THEBMOPLAST1CS A Thesis by ALI IHSAN MANISALI Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OP... SCIENCE May 1980 Major Subject: Mechanical Engineering THE STRUCTURE AND PROPERTZES OF WELD LINES IN INJECTION MOLDED THERMOPLASTICS A Thesis by ALI IHSAN MANISALI Approved as to style and content by: (Chairman of Committee) (H of Department...

  20. Welding Induced Alignment Distortion in Dual-in-Line LD Packages

    SciTech Connect (OSTI)

    Liu, Wenning N.; Sun, Xin; Khaleel, Mohammad A.; Shi, Frank G.

    2007-11-11

    The tolerance for the movement of a single mode fiber relative to the laser is extremely tight, a submicron movement can often lead to a significant misalignment and thus the reduction in the power coupled into the fiber. Among various fiber pigtailing assembly technologies, pulsed laser welding is the method with submicron accuracy and is most conducive to automation. However, the melting-solidification process during laser welding can often distort the pre-achieved fiber-optic alignment. This Welding-Induced-Alignment-Distortion (WIAD) is a serious concern and significantly affects the yield for single mode fiber pigtailing to a semiconductor laser. In this paper, effect of laser welding sequence on WIAD in a dual-in-line packager is numerically investigated by means of Finite Element Method (FEM). Optimal welding sequence may minimize WIAD in dual-in-line package. Additionally, unsymmetrical space between fiber and U-channel induced by laser welding of U-channel–to-plate in DIP LD packages is found to have obvious effect on WIAD.

  1. 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.

  2. 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.

  3. Corrosion of nickel and Monel welds of steel in chlorine trifluoride

    SciTech Connect (OSTI)

    Fout, S.L.

    1988-07-25

    Failures in the weld areas of nickel-plated steel pipe carrying chlorine trifluoride, ClF/sub 3/, prompted this investigation to determine the effect of weld composition on corrosion by ClF/sub 3/. Monel/steel and nickel/steel alloys of composition to simulate weld overlays were tested to determine their corrosion rates in ClF/sub 3/ at 200/degree/F and 300/degree/F. For both nickel/steel and Monel/steel, the corrosion rate was higher at the higher temperature. For nickel/steel alloys at compositions up to 50% iron, which would cover a range considered normal for welding, the corrosion rate would be within acceptable limits. For Monel/steel alloys, compositions up to 35% iron have an acceptable corrosion rate. Above this, the corrosion would be greater than a tolerable amount. It should pose no problem to keep the heat input to the weld low enough to produce a Monel weld with an iron content below 35%. 2 refs., 5 figs., 2 tabs.

  4. 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.

  5. A Comparative Study of Welded ODS Cladding materials for AFCI/GNEP Applications

    SciTech Connect (OSTI)

    Indrajit Charit; Megan Frary; Darryl Butt; K.L. Murty; Larry Zirker; James Cole; Mitchell Meyer; Rajiv S. Mishra; Mark Woltz

    2011-03-31

    This research project involved working on the pressure resistance welding of oxide dispersion strengthened (ODS) alloys which will have a large role to play in advanced nuclear reactors. The project also demonstrated the research collaboration between four universities and one nation laboratory (Idaho National Laboratory) with participation from an industry for developing for ODS alloys. These alloys contain a high number density of very fine oxide particles that can impart high temperature strength and radiation damage resistance suitable for in-core applications in advanced reactors. The conventional fusion welding techniques tend to produce porosity-laden microstructure in the weld region and lead to the agglomeration and non-uniform distribution of the neededoxide particles. That is why two solid state welding methods - pressure resistance welding (PRW) and friction stir welding (FSW) - were chosen to be evaluated in this project. The proposal is expected to support the development of Advanced Burner Reactors (ABR) under the GNEP program (now incorporated in Fuel Cycle R&D program). The outcomes of the concluded research include training of graduate and undergraduate students and get them interested in nuclear related research.

  6. The Future of Financial Risk Management: Lessons

    E-Print Network [OSTI]

    Aronov, Boris

    The Future of Financial Risk Management: Lessons Charles S. Tapiero, Topfer Chair Distinguished Professor of Financial Engineering and Technology Management Department of Finance and Risk Engineering NYU, leading risk managers to turn to qualitative stress testingto turn to qualitative stresstesting, 4

  7. Stress-responsive biosensors for agricultural applications

    E-Print Network [OSTI]

    Hines, George

    2013-01-01

    Stress setpoint regulation controlMemory of past heat stress . . . . . . . . . . .7.1 Memory of stress . . . . . . . . . . . 7.2 Biosensor

  8. The effects of stress on nuclear power plant operational decision making and training approaches to reduce stress effects

    SciTech Connect (OSTI)

    Mumaw, R.J.

    1994-08-01

    Operational personnel may be exposed to significant levels of stress during unexpected changes in plant state an plant emergencies. The decision making that identifies operational actions, which is strongly determined by procedures, may be affected by stress, and performance may be impaired. ER report analyzes potential effects of stress in nuclear power plant (NPP) settings, especially in the context of severe accident management (SAM). First, potential sources of stress in the NPP setting are identified. This analysis is followed by a review of the ways in which stress is likely to affect performance, with an emphasis on performance of cognitive skills that are linked to operational decision making. Finally, potential training approaches for reducing or eliminating stress effects are identified. Several training approaches have the potential to eliminate or mitigate stress effects on cognitive skill performance. First, the use of simulated events for training can reduce the novelty and uncertainty that can lead to stress and performance impairments. Second, training to make cognitive processing more efficient and less reliant on attention and memory resources can offset the reductions in these resources that occur under stressful conditions. Third, training that targets crew communications skills can reduce the likelihood that communications will fail under stress.

  9. 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

  10. Development of automated welding process for field fabrication of thick walled pressure vessels. Technical progress report, second quarter, FY 1980, ending March 28, 1980

    SciTech Connect (OSTI)

    Schneider, U.A.

    1980-01-01

    Progress on a metallurgical contract is reported: (1) specifications of 2 1/4 chromium-1 molybdenum low alloy steel plate for a coal gasification project; (2) methods of welding and analyses of helium-argon mixtures for welding; and (3) tensile properties of welded joints. (LTN)

  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. Finite element simulation of laser spot welding A. De, S. K. Maiti, C. A. Walsh and H. K. D. H. Bhadeshia

    E-Print Network [OSTI]

    Cambridge, University of

    Finite element simulation of laser spot welding A. De, S. K. Maiti, C. A. Walsh and H. K. D. H laser spot welding, taking into account the temperature dependence of the physical properties and latent formation during laser spot welding, although the `double ellipsoidal' representation requires an a priori

  13. 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

  14. The influence of laser welding parameters on the microstructure and mechanical property of the as-jointed NiTi alloy wires

    E-Print Network [OSTI]

    Zheng, Yufeng

    The influence of laser welding parameters on the microstructure and mechanical property of the as September 2007; accepted 27 November 2007 Available online 4 December 2007 Abstract The Nd:YAG laser welding.%Ni) which had the same diameter of 1 mm. The wires were welded with different parameters, including impulse

  15. To appear in The International Journal of Intelligent Automation and Soft Computing, 2003 Detection of Welding Flaws with MLP Neural Network and Case Based Reasoning

    E-Print Network [OSTI]

    Triantaphyllou, Evangelos

    Detection of Welding Flaws with MLP Neural Network and Case Based Reasoning T. Warren Liao1 *, E-Ze University, Nei-Li 32026, Chung-Li, Taiwan Abstract - The correct detection of welding flaws is important to the successful development of an automated weld inspection system. As a continuation of our previous efforts

  16. Abstract--Friction stir welding (FSW) is a relatively new and promising joining process that is the subject of much current

    E-Print Network [OSTI]

    Yao, Bin

    Abstract--Friction stir welding (FSW) is a relatively new and promising joining process that is the subject of much current research. With constant welding parameters the axial force can vary significantly due to changes in workpiece temperature and other process variations, producing welds

  17. Tool Durability Maps for Friction Stir Welding of an Aluminum Alloy T. DebRoy, A. De*, H.K.D.H. Bhadeshia**, V. D. Manvatkar*, A. Arora

    E-Print Network [OSTI]

    Cambridge, University of

    1 Tool Durability Maps for Friction Stir Welding of an Aluminum Alloy T. DebRoy, A. De*, H and Metallurgy Cambridge University Abstract Friction stir welding is not used for hard alloys because life. It is shown that fatigue is an unlikely mechanism for tool failure, particularly for the welding

  18. Modeling of Casting, Welding and Advanced Solidification Processes IX Edited by Peter R. Sahm, Preben N. Hansen and James G. Conley

    E-Print Network [OSTI]

    Taylor, Gary

    Modeling of Casting, Welding and Advanced Solidification Processes IX Edited by Peter R. Sahm to the Modelling of Welding Phenomena G. A. Taylor, M. Hughes and K. Pericleous Centre for Numerical Modelling of welding phenomena is presented. The framework includes models from both the fields of Computational Fluid

  19. 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.

  20. Growth kinetics of Al–Fe intermetallic compounds during annealing treatment of friction stir lap welds

    SciTech Connect (OSTI)

    Movahedi, M., E-mail: m_movahedi@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Ave., Tehran (Iran, Islamic Republic of); Kokabi, A.H., E-mail: kokabi@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Ave., Tehran (Iran, Islamic Republic of); Seyed Reihani, S.M., E-mail: reihani@sharif.edu [Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11365-9466, Azadi Ave., Tehran (Iran, Islamic Republic of); Najafi, H., E-mail: hossein.najafi@epfl.ch [Institute of Condensed Matter Physics (ICMP), EPFL, CH-1015 Lausanne (Switzerland); Farzadfar, S.A., E-mail: seyed-amir.farzadfar@mail.mcgill.ca [McGill University, Department of Materials Engineering, Montreal, QC H3A 2B2 (Canada); Cheng, W.J., E-mail: d9603505@mail.ntust.edu.tw [Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan, ROC (China); Wang, C.J., E-mail: cjwang@mail.ntust.edu.tw [Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan, ROC (China)

    2014-04-01

    In this study, we explored the growth kinetics of the Al–Fe intermetallic (IM) layer at the joint interface of the St-12/Al-5083 friction stir lap welds during post-weld annealing treatment at 350, 400 and 450 °C for 30 to 180 min. Optical microscope (OM), field emission gun scanning electron microscope (FEG-SEM) and transmission electron microscope (TEM) were employed to investigate the structure of the weld zone. The thickness and composition of the IM layers were evaluated using image analysis system and electron back-scatter diffraction (EBSD), respectively. Moreover, kernel average misorientation (KAM) analysis was performed to evaluate the level of stored energy in the as-welded state. The results showed that the growth kinetics of the IM layer was not governed by a parabolic diffusion law. Presence of the IM compounds as well as high stored energy near the joint interface of the as-welded sample was recognized to be the origin of the observed deviation from the parabolic diffusion law. - Highlights: • This work provided a new insight into growth kinetics of Al–Fe IM thickness. • The growth kinetics of IM layer was not governed by a parabolic diffusion law. • IM near the joint interface was the origin of deviation from the parabolic law. • High stored energy at joint interface was origin of deviation from parabolic law.

  1. 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.

  2. 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.

  3. 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

  4. Effect of tool pin features on process response variables during friction stir welding of dissimilar aluminum alloys

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

    Rabby, Reza; Tang, Wei; Reynolds, A. P.

    2015-07-01

    In this article, the effect of pin features and orientation/placement of the materials on advancing side were investigated for friction stir welding (FSW) of dissimilar aluminum alloys AA2050 and AA6061. Pins for FSW were produced with a 2.12 mm pitch thread having three flats/flutes. Three sets of rotational speed/welding speed were used to perform a series of welds in a butt joint arrangement. The results show that, joint quality, process response variables and welding temperature are highly affected by pin features and material orientation in FSW. Defect free joints with effective material transportation in the weld nugget zone were obtainedmore »when welding was performed with AA2050 on the advancing side. The tool also encounters less in-plane reaction force for welding with 2050 on the advancing side. Pin with thread+3 flats produces quality welds at low rotational and travel speed regardless of the location of alloys on advancing or retreating side.« less

  5. Details of the Electro-Mechanical (E/M) Impedance Health Monitoring of Spot-Welded Structural Joints

    E-Print Network [OSTI]

    Giurgiutiu, Victor

    1 Details of the Electro-Mechanical (E/M) Impedance Health Monitoring of Spot-Welded Structural sensors for health monitoring spot-welded structural joints. Experiments were performed on aluminum-electric transducer; Crack propagation; Crack detection. 1. INTRODUCTION Health monitoring of structural joints

  6. Application of Bayesian Neural Network for modeling and prediction of ferrite number in austenitic stainless steel welds

    E-Print Network [OSTI]

    Cambridge, University of

    in austenitic stainless steel welds M. Vasudevan, M. Murugananth*, and A.K. Bhaduri Materials Joining Section the influence of compositional variations on ferrite content for the austenitic stainless steel base content in austenitic stainless steel welds based on the optimized neural network model. Bayesian neural

  7. Tensile-stressed microelectromechanical apparatus and tiltable micromirrors formed therefrom

    DOE Patents [OSTI]

    Fleming, James G.

    2007-01-09

    A microelectromechanical (MEM) apparatus is disclosed which includes a pair of tensile-stressed actuators suspending a platform above a substrate to tilt the platform relative to the substrate. A tensile stress built into the actuators initially tilts the platform when a sacrificial material used in fabrication of the MEM apparatus is removed. Further tilting of the platform can occur with a change in the ambient temperature about the MEM apparatus, or by applying a voltage to one or both of the tensile-stressed actuators. The MEM apparatus can be used to form a tiltable micromirror or an array of such devices, and also has applications for thermal management within satellites.

  8. The Experimental Effects of Stress on Fertility

    E-Print Network [OSTI]

    Koopman, Jenna

    2013-01-01

    out alternative treatments for infertility. Stress in thebest treatments for stress-induced infertility. Acupuncture

  9. Dynamic strain gages analysis of critical welds used in power plant circuit breakers

    SciTech Connect (OSTI)

    MacDougall, E.A. ); Wilhelm, W.G. )

    1990-01-01

    A history of failures in power plant circuit breakers associated with critical welds in the internal pole shafts has been investigated. This paper describes the test, equipment, and instrumentation and summarized the preliminary results of testing performed on these breakers at Brookhaven National Laboratory. It includes the description of the instrumentation including the use of a full bridge strain gage sensor and instrumentation amplifier connected to an oscilloscope. The combination provided a sensitive instrument capable of revealing subtle changes in circuit breaker performance. The strain gages were attached to pole shafts and monitored dynamically. The observed changes in wave signature were recorded as a function of accumulated operating cycles. Complex changes in wave shape recorded on an oscillograph indicate patterns related to impending weld failure. The life expectancy measured in the number of circuit breaker open and closing cycles is compared with the weld and other component failures. 8 refs., 4 figs.

  10. An integrated model for the post-solidification shape and grain morphology of fusion welds

    E-Print Network [OSTI]

    Kidess, Anton; Duggan, Gregory; Browne, David J; Kenjereš, Saša; Richardson, Ian; Kleijn, Chris R

    2015-01-01

    Through an integrated macroscale/mesoscale computational model, we investigate the developing shape and grain morphology during the melting and solidification of a weld. In addition to macroscale surface tension driven fluid flow and heat transfer, we predict the solidification progression using a mesoscale model accounting for realistic solidification kinetics, rather than quasi-equilibrium thermodynamics. The tight coupling between the macroscale and the mesoscale distinguishes our results from previously published studies. The inclusion of Marangoni driven fluid flow and heat transfer, both during heating and cooling, was found to be crucial for accurately predicting both weld pool shape and grain morphology. However, if only the shape of the weld pool is of interest, a thermodynamic quasi-equilibrium solidification model, neglecting solidification kinetics, was found to suffice when including fluid flow and heat transfer. We demonstrate that the addition of a sufficient concentration of approximately 1 $\\...

  11. 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.

  12. Using Phased Array Ultrasonic Testing in Lieu of Radiography for Acceptance of Carbon Steel Piping Welds

    SciTech Connect (OSTI)

    Moran, Traci L.; Anderson, Michael T.; Cinson, Anthony D.; Crawford, Susan L.; Nove, Carol A.

    2014-08-01

    The Pacific Northwest National Laboratory (PNNL) is conducting studies for the U.S. Nuclear Regulatory Commission (NRC) to assess the capability, effectiveness, and reliability of ultrasonic testing (UT) as a replacement method for radiographic testing (RT) for volumetric examination of nuclear power plant (NPP) components. This particular study focused on evaluating the use of UT on carbon steel plate welds. Welding fabrication flaws included a combination of planar and volumetric types, e.g., incomplete fusion, lack of penetration, cracks, porosity, and slag inclusions. The examinations were conducted using phased-array (PA) UT techniques applied primarily for detection and flaw type characterization. This paper will discuss the results of using UT in lieu of RT for detection and classification of fabrication flaws in carbon steel plate welds.

  13. Weld overlay coatings for erosion control. Task A: Literature review, progress report

    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).

  14. 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.

  15. recently carried out an analysis of the results of cross-weld creep tests that have been reported in the literature using neural networks in a Bayesian framework [9]. This

    E-Print Network [OSTI]

    Cambridge, University of

    #12;recently carried out an analysis of the results of cross-weld creep tests that have been-weld creep testing is then described. Finally, the preliminary results of the creep testing are presented that the weld preheat temperature has a significant effect on creep life, while the weld heat input

  16. Fully-automatic laser welding and micro-sculpting with universal in situ inline coherent imaging

    E-Print Network [OSTI]

    Webster, Paul J L; Ji, Yang; Galbraith, Christopher M; Kinross, Alison W; Van Vlack, Cole; Fraser, James M

    2014-01-01

    Though new affordable high power laser technologies make possible many processing applications in science and industry, depth control remains a serious technical challenge. Here we show that inline coherent imaging, with line rates up to 312 kHz and microsecond-duration capture times, is capable of directly measuring laser penetration depth in a process as violent as kW-class keyhole welding. We exploit ICI's high speed, high dynamic range and robustness to interference from other optical sources to achieve fully automatic, adaptive control of laser welding as well as ablation, achieving micron-scale sculpting in vastly different heterogeneous biological materials.

  17. Yucca Mountain Waste Package Closure System Robotic Welding and Inspection System

    SciTech Connect (OSTI)

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

    2011-10-01

    The Waste Package Closure System (WPCS), for the closure of radioactive waste in canisters for permanent storage of spent nuclear fuel (SNF) and high-level waste in the Yucca Mountain Repository was designed, fabricated, and successfully demonstrated at the Idaho National Laboratory (INL). This article focuses on the robotic hardware and tools necessary to remotely weld and inspect the closure lid welds. The system was operated remotely and designed for use in a radiation field, due to the SNF contained in the waste packages being closed.

  18. Diagenesis of the Terry sandstone member of the Pierre Shale, Spindle field, Weld County, Colorado 

    E-Print Network [OSTI]

    Hays, Phillip Dean

    1986-01-01

    DIAGENESIS OF THE TERRY SANDSTONE MEMBER OF THE PIERRE SHALE, SPINDLE FIELD, WELD COUNTY, COLORADO A Thesis PHILLIP DEAN HAYS Submitted to the Gradute College of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE August 1986 Major Subject: Geology DIAGNESIS OF THE TERRY SANDSTONE MEMBER OF THE PIERRE SHALE ~ SP INDLE F I ELD ~ WELD COUNTY ~ COLORADO A Thesis by PHILLIP DEAN HAYS Approved as to style and content by: -, ~jD Thomas T...

  19. Overcoming the effects of acute stress through good teamwork practices

    SciTech Connect (OSTI)

    Harrington, D.K. (Team Foundation, Winston-Salem, NC (United States)); Gaddy, C.D. (General Physics Corp., Columbia, MD (United States))

    1992-01-01

    Two recent industry studies have taken a look at operators in stressful situations. In the context of severe-accident management, Mumaw et al. discussed four approaches to training operators for severe accidents: (1) training for knowledge or procedural skills; (2) training decision makers about goals and plans; (3) training to avoid cognitive biases; and (4) training within a realistic setting. These four approaches address directly the cognitive skills important for decision making. These types of training can also address indirectly the effects of stress on performance. First, effects of stress on decision making, such as reduced working memory, can be addressed by training cognitive skills. Second, exposure to realistically stressful situations can reduce the novelty and uncertainty, which is a primary cause of stress reactions. In a second study reported by Desaulniers, the stress of requalification exams was the focus. Desaulniers concluded that repeated changes in the exam process, inconsistency in interpretation of examiner guidelines, and some content and grading practices resulted in undue stress for the operators. The US Nuclear Regulatory Commission staff actions to remedy these sources of undue stress were described.

  20. 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.

  1. 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.

  2. Paraxial ray-tracing approach for the simulation of ultrasonic inspection of welds

    SciTech Connect (OSTI)

    Gardahaut, Audrey; Jezzine, Karim [CEA, LIST, Digiteo Labs, Bât 565, PC 120, F-91191, Gif-sur-Yvette (France); Cassereau, Didier [CNRS, UMR 7623, LIP, 15 rue de l'école de médecine, 75006 Paris, France and ESPCI ParisTech, 10 rue Vauquelin, 75005 Paris (France)

    2014-02-18

    On-site inspection of bimetallic or austenitic welds can be very difficult to interpret owing to their internal structures. Skewing and splitting of the ultrasonic beam may occur due to the anisotropic and inhomogeneous properties of the welding material. In this paper, we present a ray-based method to simulate the propagation of ultrasonic waves in such structures. The formalism is based on dynamic ray tracing system in Cartesian coordinates along a reference ray. Standard ray tracing consists in the solution of a system of linear ordinary differential equations of the first order and is used to determine the trajectory of the ray. Likewise, dynamic ray tracing (DRT) also called paraxial ray tracing consists in the solution of an additional system of linear ordinary differential equations along the ray allowing paraxial quantities to be computed. It is used to evaluate the geometrical spreading and amplitude along the ray and in its vicinity. DRT is applied on a smooth representation of the elastic properties of the weld obtained thanks to an image processing technique applied on a macrograph of the weld. Simulation results are presented and compared to finite elements and experimental results.

  3. Modelling and Visualisation of Material Flow in Friction Stir Spot Welding

    E-Print Network [OSTI]

    Reilly, Aidan; Shercliff, Hugh; Chen, Yingchun; Prangnell, Philip

    2015-06-23

    protrudes right through the upper sheet to the tool interface, pushing the interface downwards in the weld centre. This stretches the bond line, exposing new clean surface and contributing to break-up of the oxide layer – though in FSSW the normal strains...

  4. Welding an LHC bending magnet held in place by CERN?s hydraulic press

    E-Print Network [OSTI]

    Laurent Guiraud

    1998-01-01

    A powerful hydraulic press has been installed at CERN. Rated at 27 000 tonnes, it has enough force to lift a weight equivalent to almost four Eiffel towers. The press is used to hold magnets in place as their casings are welded together or opened up.

  5. Unsaturated flow and transport through a fault embedded in fractured welded tuff

    E-Print Network [OSTI]

    Hu, Qinhong "Max"

    in locations where there is environmental contamination or the poten- tial for disposal of radioactive waste [Native et al., 1995], and the proposed radioactive waste repository in the tuff forma- tions at YuccaUnsaturated flow and transport through a fault embedded in fractured welded tuff Rohit Salve, Hui

  6. ~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

  7. 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

  8. Finite element simulation of magnetic detection of creep damage at seam welds

    SciTech Connect (OSTI)

    Sablik, M.J.; Rubin, S.W.; Jiles, D.C.; Kaminski, D.; Bi, Y.

    1996-09-01

    Using appropriately modified magnetization curves for each element of creep-damaged material, a finite element calculation has been carried out to simulate magnetic detection of non-uniform creep damage around a seam weld in a 2.25 Cr 1 Mo steam pipe. The magnetization curves for the creep-damaged elements were obtained from an earlier model for the magnetic effect of a uniformly creep-damaged material as given by Chen, et al. In the finite element calculation, a magnetic C-core with primary and secondary coils was placed with its pole pieces flush against the specimen in the vicinity of the weld. The secondary emf was shown to be reduced when creep damage was present inside the pipe wall at the cusp of weld and in the vicinity of the cusp. The C-core detected the creep damage best if it completely spanned the weld seam width. Also, the current in the primary needed to be such that the C-core was not magnetically saturated.

  9. Deformation and Fracture of Miniature Tensile Bars with Resistance-Spot-Weld Microstructures

    E-Print Network [OSTI]

    Tong, Wei

    mixture in dual-phase steels is typically produced after annealing in the so-called inter- critical Plastic deformation of miniature tensile bars generated from dual-phase steel weld microstructures (i-phase steels are being actively investigated for future automotive applications.[1] The term "dual-phase steel

  10. Nickel-Based Superalloy Welding Practices for Industrial Gas Turbine Applications M.B. Henderson

    E-Print Network [OSTI]

    Cambridge, University of

    1 Nickel-Based Superalloy Welding Practices for Industrial Gas Turbine Applications M.B. Henderson and reduced costs for industrial gas turbine engines demands extended use of high strength-high temperature superalloys are used within the industrial gas turbine (IGT) engine manufacturing industry, specifically

  11. PINCH WELD TESTING TO SUPPORT CHANGE IN MANUFACTURING OIL AT THE KCP

    SciTech Connect (OSTI)

    Korinko, P; David Maxwell, D

    2008-02-28

    This task supports the change from an oil mixture termed 50:50 oil (an equal parts mixture of Milpro 634 and Pennex N47) to a new oil mixture (Castrol Illocut 334). This change was necessitated by a KCP vendor no longer supplying the Pennex N47 component of the 50-50. In order to continue production of machined parts, a detailed process was followed to ensure that high quality parts could be manufactured and that the cutting oil selected would provide acceptable human performance characteristics, e.g., skin irritability, smell, etc. A prime consideration in changing the oil was that no apparent change in the pinch weldability of the fill stems fabricated using the new oil and process parameters, if any, be observed. A two part approach, as detailed in the plan shown in Appendix B, was used to qualify the effect of the process on pinch weld characteristics. In the first phase, ref. 1., the weld parameter window was defined using fill stems made from 304L, 21-6-9, and 316 stainless steel. These weld conditions were then subsequently used for the Castrol Illocut 334 machined fill stems. The results of this activity are reported in this document. A follow-on task of welding in the facility was requested by one of the design agencies and this will be completed and reported separately.

  12. Optimized Sampling Frequencies for Weld Reliability Assessments of Long Pipeline Segments

    E-Print Network [OSTI]

    Kreinovich, Vladik

    Optimized Sampling Frequencies for Weld Reliability Assessments of Long Pipeline Segments Cesar J that design an optimal testing strategy for long pipeline segments. I. INTRODUCTION Inspecting Pipelines buried pipelines. High­pressure corrosive substances transported within a pipeline and often severe soil

  13. Optimized Sampling Frequencies for Weld Reliability Assessments of Long Pipeline Segments

    E-Print Network [OSTI]

    Kreinovich, Vladik

    Optimized Sampling Frequencies for Weld Reliability Assessments of Long Pipeline Segments Cesar J that design an optimal testing strategy for long pipeline segments. I. INTRODUCTION Inspecting Pipelines buried pipelines. High-pressure corrosive substances transported within a pipeline and often severe soil

  14. Influence of filler wire composition on weld microstructures of a 444 ferritic stainless steel grade

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Influence of filler wire composition on weld microstructures of a 444 ferritic stainless steel, wetting and grain structure of the fusion zone. Keywords: ferritic stainless steel, GMAW, filler wire) presented a new design approach to replace traditional manifolds made of cast iron to stainless steel tubes

  15. Extracting yeast stress genes by dependencies between stress treatments

    E-Print Network [OSTI]

    Kaski, Samuel

    Extracting yeast stress genes by dependencies between stress treatments Arto Klamia,b , Janne, Finland c Medicel Oy, Helsinki, Finland 17 data sets from different stress treatments, obtained from two different sources (Gasch et al. 2000, Causton et al. 2001) Heat (3), acid, alkali, peroxide, Na

  16. Method and design for externally applied laser welding of internal connections in a high power electrochemical cell

    DOE Patents [OSTI]

    Martin, Charles E; Fontaine, Lucien; Gardner, William H

    2014-01-21

    An electrochemical cell includes components that are welded from an external source after the components are assembled in a cell canister. The cell canister houses electrode tabs and a core insert. An end cap insert is disposed opposite the core insert. An external weld source, such as a laser beam, is applied to the end cap insert, such that the end cap insert, the electrode tabs, and the core insert are electrically coupled by a weld which extends from the end cap insert to the core insert.

  17. Estimate of the allowable dimensions of diagnosed defects in category III and IV welded pipeline joints{sup 1}

    SciTech Connect (OSTI)

    Grin', E. A.; Bochkarev, V. I.

    2013-01-15

    An approach for estimating the permissible dimensions of technological defects in butt welded joints in category III and IV pipelines is described. The allowable size of a welding defect is determined from the condition of compliance with the specifications on strength for a reference cross section (damaged joint) of the pipeline taking into account its weakening by a given defect.With regard to the fairly widespread discovery of technological defects in butt welded joints during diagnostics of auxiliary pipelines for thermal electric power plants, the proposed approach can be used in practice by repair and consulting organizations.

  18. Irradiation-Assisted Stress Corrosion Cracking of Austenitic Stainless Steels in BWR Environments

    SciTech Connect (OSTI)

    Chen, Y.; Chopra, O. K.; Gruber, Eugene E.; Shack, William J.

    2010-06-01

    The internal components of light water reactors are exposed to high-energy neutron irradiation and high-temperature reactor coolant. The exposure to neutron irradiation increases the susceptibility of austenitic stainless steels (SSs) to stress corrosion cracking (SCC) because of the elevated corrosion potential of the reactor coolant and the introduction of new embrittlement mechanisms through radiation damage. Various nonsensitized SSs and nickel alloys have been found to be prone to intergranular cracking after extended neutron exposure. Such cracks have been seen in a number of internal components in boiling water reactors (BWRs). The elevated susceptibility to SCC in irradiated materials, commonly referred to as irradiation-assisted stress corrosion cracking (IASCC), is a complex phenomenon that involves simultaneous actions of irradiation, stress, and corrosion. In recent years, as nuclear power plants have aged and irradiation dose increased, IASCC has become an increasingly important issue. Post-irradiation crack growth rate and fracture toughness tests have been performed to provide data and technical support for the NRC to address various issues related to aging degradation of reactor-core internal structures and components. This report summarizes the results of the last group of tests on compact tension specimens from the Halden-II irradiation. The IASCC susceptibility of austenitic SSs and heat-affected-zone (HAZ) materials sectioned from submerged arc and shielded metal arc welds was evaluated by conducting crack growth rate and fracture toughness tests in a simulated BWR environment. The fracture and cracking behavior of HAZ materials, thermally sensitized SSs and grain-boundary engineered SSs was investigated at several doses (?3 dpa). These latest results were combined with previous results from Halden-I and II irradiations to analyze the effects of neutron dose, water chemistry, alloy compositions, and welding and processing conditions on IASCC. The effect of neutron irradiation on the fracture toughness of austenitic SSs was also evaluated at dose levels relevant to BWR internals.

  19. In mold laser welding for high precision polymer based optical components

    SciTech Connect (OSTI)

    Oliveira, N., E-mail: id2694@alunos.uminho.pt, E-mail: pontes@dep.uminho.pt; Pontes, A. J., E-mail: id2694@alunos.uminho.pt, E-mail: pontes@dep.uminho.pt [IPC - Institute for Polymers and Composites, Department of Polymer Engineering, University of Minho, 4800-058 Guimarães (Portugal)

    2014-05-15

    To assemble a complete subsystem as a rear lamp, is necessary to have different machines and to perform several tasks. This necessity obliges the companies to have large structures to support all the assembling process. These huge structures are very costly and have as a consequence the reduction of the competitiveness of the companies. The process presented in this document has the intention of reducing the number of tasks needed to produce the final subsystem/product. To achieve this goal were combined several technologies, as in-mould assembling, laser welding and LEDs (light-emitting diode). One of the advantages of this process was the utilization of only one injection molding machine with three injection units to do all the assembling process. To achieve the main objective, firstly, the rear lamp was designed according to with the legislation of UNECE Vehicle Regulations - 1958 Agreements; Regulation No. 50 -Rev.2 - Position lamps, stop lamps, direction indicators for motorcycles. Posterior several polymeric materials were studied at different levels. Initial were studied several concentrations of carbon nanotubes mixed with PC (polycarbonate). This had the objective of determine, if these materials are suitable to conduct the necessary electric current to turn on the different LEDs. One of the main advantages of this process is the use of the laser transmission welded process. Since, with this welding technology is possible reduce the complexity of the final part. To understand the potentialities of this technology a combination of two materials was studied. The studied showed that all materials presented a high transparency to the laser beam. In terms of weld process, the study showed that the best welding conditions are the lowest velocity, diameter and power. With these studies was possible conclude that this new process is suitable to be implemented at the industrial level.

  20. Toolbox Safety Talk Heat Stress

    E-Print Network [OSTI]

    Pawlowski, Wojtek

    Toolbox Safety Talk Heat Stress Environmental Health & Safety Facilities Safety & Health Section for inducing heat stress. When the body is unable to cool itself by sweating, several heat-induced illnesses Stress · Know signs/symptoms of heat-related illnesses; monitor yourself and coworkers. · Block out