Principles Of Welding

PRINCIPLES OF WELDING Processes, Physics, Chemistry, and Metallurgy ROBERT W. MESSLER, Jr. Materials Science and Engineering Department Rensselaer Polytechnic Institute Troy, NY WILEYVCH WILEY-VCH Verlag GmbH & Co. KGaA This Page Intentionally Left Blank PRINCIPLES OF WELDING This Page Intentionally Left Blank PRINCIPLES OF WELDING Processes, Physics, Chemistry, and Metallurgy ROBERT W. MESSLER, Jr. Materials Science and Engineering Department Rensselaer Polytechnic Institute Troy, NY WILEYVCH WILEY-VCH Verlag GmbH & Co. KGaA All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate. Library of Congress Card No.: Applied for British Library Cataloging-in-Publication Data: A catalogue record for this book is available from the British Library Bibliographic information published by Die Deutsche Bibliothek Die Deutsche Bibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at . 0 1999 by John Wiley & Sons, Inc. 02004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim All rights reserved (including those oftranslation into other languages). No part of this book may be reproduced in any form - nor transmitted or translated into machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even whcn not specifically marked as such, are not to be considered unprotected by law. Printed in Singapore Printed on acid-free paper Cover Illustration Avram Kaufman Printing and Bookbinding Markono Print Media Pte Ltd, Singapore ISBN-13: 978-0-471-25376-1 ISBN-10: 0-47 1-25376-6 CONTENTS PREFACE xix I THEPROCESSANDPROCESSESOFWELDING 1 INTRODUCTION TO THE PROCESS OF WELDING 3 What Is Welding? / 3 The Evolution of Welding as a Process / 6 The Nature of an Ideal Weld: Achieving Continuity / 7 Impediments to Making Ideal Welds in the Real World / 10 1.5 What It Takes to Make a Real Weld / 12 1.6 Advantages and Disadvantages of Welding / 14 1.7 Summary / 15 References and Suggested Reading / 15 1.1 1.2 1.3 1.4 2 CLASSIFYING WELDING PROCESSES 2.1 2.2 2.3 2.4 17 Why Classify Processes? / 17 Mechanisms for Obtaining Material Continuity / 18 The Roles of Temperature and Pressure / 21 Alternative Bases for Classification / 23 2.4.1 Fusion Versus Nonfusion / 23 2.4.2 Pressure Versus Nonpressure / 25 2.4.3 Energy Source for Welding / 25 V Vl CONTENTS 2.4.4 Interface Relationships and Classification by Energy Transfer Processes / 27 2.4.5 Other Bases for Classification and Subclassification / 28 2.5 Allied Processes / 35 2.6 The AWS Classification Scheme / 37 2.7 Summary / 39 References and Suggested Reading / 39 3 FUSION WELDING PROCESSES 3.1 General Description of Fusion Welding Processes / 40 3.2 Chemical Fusion Welding Processes / 41 3.2.1 Oxyfuel Gas Welding / 41 3.2.2 Aluminothermic Welding / 46 3.3 Electric Arc Welding Processes / 49 3.3.1 Nonconsumable Electrode Arc Welding Processes / 50 3.3.1.1 Gas-Tungsten Arc Welding / 51 3.3.1.2 Plasma Arc Welding / 55 3.3.1.3 Magnetically Impelled Arc Butt Welding 1'57 3.3.2 Consumable Electrode Arc Welding Processes / 60 3.3.2.1 Gas-Metal Arc Welding / 60 3.3.2.2 Shielded-Metal Arc Welding / 64 3.3.2.3 Flux-Cored Arc Welding / 66 3.3.2.4 Submerged Arc Welding / 68 3.3.2.5 Electrogas Welding / 69 3.3.2.6 Electroslag Welding / 70 3.4 Resistance Welding Processes / 71 3.4.1 Resistance Spot, Resistance Seam, and Projection Welding / 71 3.4.2 Fla