Welding Handbook Ninth Edition Volume 3 WELDING PROCESSES, PART 2 Prepared under the direction of the Welding Handbook Committee Annette O’Brien, Editor Carlos Guzman, Associate Editor American Welding Society 550 N.W. LeJeune Road Miami, FL 33126 iii © 2007 by American Welding Society All rights reserved No portion of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, including mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyright owner. Authorization to photocopy items for internal, personal, or educational classroom use only, or the internal, personal, or educational classroom use only of specific clients, is granted by the American Welding Society (AWS) provided the appropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923; telephone: (978) 750-8400; Internet: www.copyright.com. Library of Congress Control Number: 2001089999 ISBN: 978-0-87171-053-6 The Welding Handbook is the result of the collective effort of many volunteer technical specialists who provide information to assist with the design and application of welding and allied processes. The information and data presented in the Welding Handbook are intended for informational purposes only. Reason- able care is exercised in the compilation and publication of the Welding Handbook to ensure the authenticity of the contents. However, no representation is made as to the accuracy, reliability, or completeness of this information, and an independent substantiating investigation of the information should be undertaken by the user. The information contained in the Welding Handbook shall not be construed as a grant of any right of manufacture, sale, use, or reproduction in connection with any method, process, apparatus, product, composition, or system, which is covered by patent, copyright, or trademark. Also, it shall not be construed as a defense against any liability for such infringement. Whether the use of any information in the Welding Handbook would result in an infringement of any patent, copyright, or trademark is a determination to be made by the user. Printed in the United States of America iv PREFACE This is Volume 3 of the Welding Handbook, the third of the five-volume series in the Ninth Edition. Following the publication of Welding Handbook Volume 1, Welding Science and Technology, the Welding Handbook Committee determined that one volume could no longer contain the process technology described in the 29 chapters of Volume 2, Eighth Edition; thus Volume 2 and Volume 3 of the Ninth Edition were designed to accommodate the expanded information. Welding Processes, Part 1 presented updated information on arc welding and cutting, the gas processes, brazing, and soldering. This volume, Welding Processes, Part 2 is devoted to information on resistance welding, solid state processes and other joining and cutting methods. Volumes 4 and 5 of the Ninth Edition of the Welding Handbook will address welding materials and applications. Volume 3 contains updated resistance welding chapters: spot and seam welding, projection welding, flash and upset welding, high-frequency welding, and resistance welding equipment. The chapter on friction welding has been updated, and new in this edition, a separate chapter on the developing process variation, friction stir welding, has been added. Other chapters are ultrasonic welding, explosion welding, adhesive bonding, thermal spraying and cold spraying, diffusion welding and diffusion brazing. The chapters on electron beam welding and laser beam welding and cutting contain significantly expanded technology. The last chapter, Other Welding and Cutting Processes, contains information on two new or revitalized processes, magnetic pulse welding, and electro-spark depositing. New information is presented on water jet cutting, which is reappearing in many current applications as a modern, efficient process. A table of contents of each chapter is outlined on the cover page, and a subject index with cross-references appears at the end of the volume. A major subject index of this volume and previous editions of the Welding Handbook is included. Appendices A and B are lists of safety standards, and Appendix C presents a list of SI/inch-pound conversions of commonly used pressure units. The chapters in this volume reflect the dramatic changes brought into welding processes over the past decade by the precise control of welding parameters made possible with digital controls and microprocessors as applied to new techniques and advanced materials. To meet the challenge of including this expanded technology, each chapter was prepared by a committee made up of highly qualified experts enthusiastic about the subject process, and headed by a chapter chair with an admirable dedication to the details of infusing state-of the-art information into the basics of the processes. All committee members are volunteers who generously devoted countless hours of personal time to the chapters. One hundred and ten American Welding Society volunteers contributed to this book, representing university, government, and private welding research and development institutions, manufacturers of welding equipment and materials, and manufacturers, fabricators, and welders who use this technology. The Welding Handbook Committee welcomes your comments and suggestions. Please address them to the Editor, Welding Handbook, American Welding Society, 550 N. W. LeJeune Road, Miami, FL 33126. Phillip I. Temple, Chair Richard C. DuCharme, Chair Welding Handbook Committee Welding Handbook Volume 3 Committee Annette O’Brien, Senior Editor Welding Handbook xiii CONTENTS ACKNOWLEDGMENTS...................................................................................................................................xii PREFACE...........................................................................................................................................................xiii REVIEWERS......................................................................................................................................................xiv CONTRIBUTORS..............................................................................................................................................xv CHAPTER 1—RESISTANCE SPOT AND SEAM WELDING....................................................................1 Introduction..........................................................................................................................................................2 Fundamentals........................................................................................................................................................2 Equipment...........................................................................................................................................................11 Surface Preparation for Spot and Seam Welding..................................................................................................14 Resistance Spot Welding......................................................................................................................................15 Resistance Seam Welding.....................................................................................................................................26 Metal Properties and Weldability.........................................................................................................................39 Economics of Resistance Welding........................................................................................................................43 Safe Practices.......................................................................................................................................................43 Conclusion..........................................................................................................................................................45 Bibliography........................................................................................................................................................45 CHAPTER 2—PROJECTION WELDING...................................................................................................49 Introduction........................................................................................................................................................50 Equipment...........................................................................................................................................................52 Welding Variables................................................................................................................................................55 Welding Schedules...............................................................................................................................................62 Metals Welded.....................................................................................................................................................63 Weld Quality.......................................................................................................................................................63 Cross Wire Welding.............................................................................................................................................66 Economics...........................................................................................................................................................69 Safe Practices.......................................................................................................................................................69 Bibliography........................................................................................................................................................71 CHAPTER 3—FLASH AND UPSET WELDING........................................................................................73 Introduction........................................................................................................................................................74 Flash Welding......................................................................................................................................................74 Fundamentals......................................................................................................................................................75 Applications........................................................................................................................................................76 Equipment...........................................................................................................................................................77 Welding Procedures.............................................................................................................................................79 Welding Machine Settings....................................................................................................................................92 Upset Welding.....................................................................................................................................................94 Fundamentals......................................................................................................................................................94 Process Variations................................................................................................................................................94 Applications........................................................................................................................................................94 Sheet, Strip, and Wire Welding............................................................................................................................95 Continuous Upset Welding..................................................................................................................................98 Weld Quality.....................................................................................................................................................100 Examination and Testing...................................................................................................................................102 Economics.........................................................................................................................................................103 Safe Practices.....................................................................................................................................................103 Conclusion........................................................................................................................................................104 Bibliography......................................................................................................................................................105 vii CHAPTER 4—RESISTANCE WELDING EQUIPMENT.........................................................................107 Introduction.......................................................................................................................................................108 Equipment Selection...........................................................................................................................................108 Electrodes...........................................................................................................................................................123 Actuators...........................................................................................................................................................133 Power Conversion Equipment............................................................................................................................135 Resistance Welding Controls..............................................................................................................................142 Quality Control Functions.................................................................................................................................152 Electric Service Equipment.................................................................................................................................153 Economics..........................................................................................................................................................154 Safe Practices......................................................................................................................................................155 Conclusion.........................................................................................................................................................157 Bibliography.......................................................................................................................................................158 CHAPTER 5—HIGH-FREQUENCY WELDING........................................................................................159 Introduction.......................................................................................................................................................160 Fundamentals.....................................................................................................................................................160 Applications.......................................................................................................................................................165 Induction Seam Welding of Pipe and Tubing......................................................................................................165 Contact Seam Welding of Pipe and Tubing.........................................................................................................166 Welding Parameters............................................................................................................................................169 Equipment..........................................................................................................................................................169 Inspection and Quality Control..........................................................................................................................178 Economics..........................................................................................................................................................179 Safe Practices......................................................................................................................................................180 Conclusion.........................................................................................................................................................180 Bibliography......................................................................................................................................................181 CHAPTER 6—FRICTION WELDING.........................................................................................................183 Introduction.......................................................................................................................................................184 Fundamentals.....................................................................................................................................................184 Welding Variables...............................................................................................................................................191 Joint Design.......................................................................................................................................................197 Equipment..........................................................................................................................................................198 Welding Procedures............................................................................................................................................202 Applications.......................................................................................................................................................203 Weld Quality......................................................................................................................................................203 Economics..........................................................................................................................................................205 Safe Practices......................................................................................................................................................205 Conclusion.........................................................................................................................................................208 Bibliography.......................................................................................................................................................208 CHAPTER 7—FRICTION STIR WELDING..............................................................................................211 Introduction.......................................................................................................................................................212 Fundamentals.....................................................................................................................................................212 Equipment and Controls....................................................................................................................................214 Tool Design........................................................................................................................................................217 Welding Parameters............................................................................................................................................219 Regions of a Friction Stir Weld...........................................................................................................................220 Factors Affecting Weldability.............................................................................................................................222 Heat Transfer.....................................................................................................................................................232 Material Flow....................................................................................................................................................236 Applications.......................................................................................................................................................238 viii Mechanical Properties.......................................................................................................................................239 Weld Quality.....................................................................................................................................................247 Economics.........................................................................................................................................................252 Safe Practices.....................................................................................................................................................253 Conclusion........................................................................................................................................................253 Bibliography......................................................................................................................................................253 CHAPTER 8—ULTRASONIC WELDING..................................................................................................263 Introduction......................................................................................................................................................264 Fundamentals....................................................................................................................................................264 Equipment.........................................................................................................................................................271 Welding Variables and Procedures.....................................................................................................................276 Metals Welded...................................................................................................................................................280 Applications......................................................................................................................................................283 Mechanisms of Ultrasonic Welding....................................................................................................................285 Ultrasonic Microwelding...................................................................................................................................291 Weld Quality.....................................................................................................................................................295 Economics.........................................................................................................................................................300 Safe Practices.....................................................................................................................................................300 Conclusion........................................................................................................................................................301 Bibliography......................................................................................................................................................301 CHAPTER 9—EXPLOSION WELDING....................................................................................................303 Introduction......................................................................................................................................................304 Fundamentals....................................................................................................................................................304 Equipment and Facilities...................................................................................................................................308 Testing Equipment.............................................................................................................................................312 Welding Variables..............................................................................................................................................312 Materials...........................................................................................................................................................314 Applications......................................................................................................................................................316 Cylinders...........................................................................................................................................................319 Transition Joints................................................................................................................................................320 Heat Exchangers...............................................................................................................................................323 Weld Quality and Testing..................................................................................................................................324 Economics.........................................................................................................................................................327 Safe Practices.....................................................................................................................................................329 Conclusion........................................................................................................................................................329 Bibliography......................................................................................................................................................329 CHAPTER 10—ADHESIVE BONDING....................................................................................................333 Introduction......................................................................................................................................................334 Fundamentals....................................................................................................................................................334 Adhesives..........................................................................................................................................................341 Joint Design.......................................................................................................................................................347 Surface Preparation...........................................................................................................................................353 Procedures.........................................................................................................................................................355 Equipment.........................................................................................................................................................358 Quality Control.................................................................................................................................................358 Economics.........................................................................................................................................................360 Safe Practices.....................................................................................................................................................361 Conclusion........................................................................................................................................................363 Bibliography......................................................................................................................................................364 ix CHAPTER 11—THERMAL SPRAYING AND COLD SPRAYING........................................................367 Introduction.......................................................................................................................................................368 Fundamentals.....................................................................................................................................................369 Process Variables................................................................................................................................................371 Process Variations..............................................................................................................................................378 Equipment and Materials...................................................................................................................................387 Characteristics of Spray-Deposited Materials.....................................................................................................396 Post-Spray Treatments........................................................................................................................................403 Applications.......................................................................................................................................................405 Quality Assurance..............................................................................................................................................409 Economics..........................................................................................................................................................410 Safe Practices......................................................................................................................................................412 Conclusion.........................................................................................................................................................417 Bibliography.......................................................................................................................................................418 CHAPTER 12—DIFFUSION WELDING AND DIFFUSION BRAZING...............................................421 Introduction.......................................................................................................................................................422 Advantages and Limitations...............................................................................................................................422 Surface Preparation............................................................................................................................................423 Diffusion Welding..............................................................................................................................................424 Fundamentals.....................................................................................................................................................424 Applications.......................................................................................................................................................426 Process Variables................................................................................................................................................426 Process Variations..............................................................................................................................................428 Techniques.........................................................................................................................................................429 Equipment..........................................................................................................................................................430 Tooling...............................................................................................................................................................433 Metals Welded...................................................................................................................................................433 Diffusion Brazing...............................................................................................................................................437 Methods.............................................................................................................................................................438 Variables............................................................................................................................................................439 Equipment and Tooling......................................................................................................................................441 Materials and Applications................................................................................................................................442 Diffusion Soldering............................................................................................................................................445 Applications.......................................................................................................................................................446 Inspection of DFW and DFB Joints....................................................................................................................446 Economics..........................................................................................................................................................447 Safe Practices......................................................................................................................................................447 Conclusion.........................................................................................................................................................448 Bibliography......................................................................................................................................................448 CHAPTER 13—ELECTRON BEAM WELDING.......................................................................................451 Introduction.......................................................................................................................................................452 Fundamentals.....................................................................................................................................................452 Equipment..........................................................................................................................................................468 Welding Procedures............................................................................................................................................484 Selection of Welding Variables............................................................................................................................488 Applications.......................................................................................................................................................493 Weld Quality......................................................................................................................................................494 Economics..........................................................................................................................................................499 Safe Practices......................................................................................................................................................499 Conclusion.........................................................................................................................................................501 Bibliography.......................................................................................................................................................501 x CHAPTER 14—LASER BEAM WELDING, CUTTING AND ASSOCIATED PROCESSES............503 Introduction......................................................................................................................................................504 Fundamentals of Laser Beam Welding and Cutting...........................................................................................505 Laser Beam Welding..........................................................................................................................................506 Laser Beam Systems...........................................................................................................................................507 Welding Techniques...........................................................................................................................................521 Applications......................................................................................................................................................524 Joint Design.......................................................................................................................................................528 Laser Beam Cutting...........................................................................................................................................530 Principles of Cutting and Drilling......................................................................................................................531 Equipment.........................................................................................................................................................539 Materials...........................................................................................................................................................544 Process Variables...............................................................................................................................................546 Quality..............................................................................................................................................................554 Economics of Laser Beam Welding and Cutting................................................................................................554 Safe Practices.....................................................................................................................................................555 Conclusion........................................................................................................................................................558 Bibliography......................................................................................................................................................558 CHAPTER 15—OTHER WELDING AND CUTTING PROCESSES....................................................561 Introduction......................................................................................................................................................562 Forge Welding...................................................................................................................................................562 Early Arc Welding.............................................................................................................................................564 Hot Pressure Welding........................................................................................................................................566 Thermite Welding..............................................................................................................................................573 Cold Welding.....................................................................................................................................................583 Magnetic Pulse Welding.....................................................................................................................................592 Electro-Spark Deposition...................................................................................................................................598 Percussion Welding............................................................................................................................................602 Water Jet Cutting...............................................................................................................................................607 Conclusion........................................................................................................................................................613 Bibliography......................................................................................................................................................613 APPENDIX A—AMERICAN WELDING SOCIETY SAFETY AND HEALTH STANDARDS LIST.......................................................................................................................................617 APPENDIX B—SAFETY CODES AND OTHER STANDARDS............................................................619 APPENDIX C—CONVERSIONS FOR VARIOUS PRESSURE UNITS...............................................623 MAJOR SUBJECT INDEX: Volumes 1, 2, and 3—Ninth Edition, and Volumes 3 and 4—Eighth Edition............................625 INDEX OF VOLUME 3, NINTH EDITION...............................................................................................645 xi AWS WELDING HANDBOOK 9.3 1 CCHAHPATPERT E1 R 9 Prepared by the Welding Handbook RESISTANCE Chapter Committee on Resistance Spot and Seam Welding: J. W. Dolfi, Chair SPOT AND SEAM Ford Motor Company (Ret.) J. E. Gould Edison Welding Institute WELDING M. J. Karagoulis General Motors Corporation B. G. Kelly Kelly Welding Solutions, P.C. C. J. Orsette RoMan Engineering Services W. Urech Soudronic Automotive Welding Handbook Committee Member: S. P. Moran Miller Electric Manufacturing Company Contents Introduction 2 Fundamentals 2 Equipment 11 Surface Preparation 14 Resistance Spot Welding 15 Resistance Seam Welding 26 Metal Properties and Weldability 39 Economics 43 Safe Practices 43 Conclusion 45 Bibliography 45 Supplementary Reading List 46 Photograph courtesy of Soudronic Automotive AG 2 AWS WELDING HANDBOOK 9.3 CHAPTER 1 RESISTANCE SPOT AND SEAM WELDING INTRODUCTION Spot welding and seam welding are resistance weld- cans and containers of all types. Other products of spot ing processes. Resistance welding includes a group of and seam welding are furnace heat exchangers and processes that produce coalescence of the faying sur- storage tanks. faces with the heat obtained from the resistance of the This chapter covers the fundamental principles of workpieces to the flow of the welding current in a cir- these processes and their variations, equipment, and cuit of which the workpieces are a part, and by the mechanical systems. The advantages and limitations of application of pressure. the processes are discussed, and welding conditions as A resistance spot weld is made between or on over- applied to various metals are presented. Other topics lapping members (workpieces) in which coalescence include joint design, welding schedules, surface prepa- may start and occur on the faying surfaces, or may pro- ration, weld quality, and economics. The chapter con- ceed from the outer surface of one member. The weld cludes with a section on safe practices specific to the cross section is approximately circular. spot and seam welding processes. A seam weld is a continuous weld made between or on overlapping members, in which coalescence may start and occur on the faying surfaces, or may have pro- ceeded from the outer surface of one member. The con- tinuous weld may consist of a single weld bead or a series of overlapping spot welds.1,2 FUNDAMENTALS Spot welding and seam welding adapt well to auto- mation. They are mainstay processes in the automotive industry and in other industries that manufacture prod- In resistance spot welding and seam welding, the ucts involving the welding of similar thicknesses of the coalescence of metals is produced by the heat generated same metal. Examples include automobile fuel tanks, in the workpieces due to resistance to the passage of catalytic converters, mufflers, and roof joints. Seam electric current through each workpiece. Force, exerted welding is an important process for manufacturers of on the joint through the electrodes, is always applied before, during, and after the application of current to confine the weld contact area at the faying surfaces and, in some applications, to forge the weld metal during 1. Welding terms and definitions used throughout this chapter are postheating. fromStandard Welding Terms and Definitions, AWS A3.0:2001, Miami: American Welding Society. A resistance welding electrode is the part of a resis- 2. At the time of the preparation of this chapter, the referenced codes tance welding machine through which the welding cur- and other standards were valid. If a code or other standard is cited rent and (in most cases) force are applied directly to the without a date of publication, it is understood that the latest edition workpiece. The electrode may be in the form of a rotat- of the document referred to applies. If a code or other standard is cited with the date of publication, the citation refers to that edition ing wheel, rotating roll, bar, cylinder, plate, clamp, only, and it is understood that any future revisions or amendments to chuck, or a modification of one of these. the code or standard are not included; however, as codes and stan- Figure 1.1 illustrates the mechanisms of the two dards undergo frequent revision, the reader is encouraged to consult the most recent edition. processes.