Quality In Resistance Welding

Drawing on state-of-the-art research results, Resistance Welding: Fundamentals and Applications, Second Edition systematically presents fundamental aspects of important processes in resistance welding and discusses their implications on real-world welding applications. This updated edition describes progress made in resistance welding research and

Many developments in resistance welding techniques have been pioneered by researchers at NV Philips International's Centre for Production Techniques. This body has published research projects over the last 20 years on topics in this area. This information has been collected in this special report.

High-performance steels and aluminum alloys pose significant challenges to resistance welding processes. Unfortunately for students in materials science, metallurgy, and manufacturing, most available books provide only a superficial treatment of resistance spot welding. Surveying the topic in a scientific and systematic manner, Resistance Welding:

Drawing on state-of-the-art research results, Resistance Welding: Fundamentals and Applications, Second Edition systematically presents fundamental aspects of important processes in resistance welding and discusses their implications on real-world welding applications. This updated edition describes progress made in resistance welding research and practice since the publication of the first edition. New to the Second Edition: Significant addition of the metallurgical aspects of materials involved in resistance welding, such as steels, aluminum and magnesium alloys, zinc, and copper Electric current waveforms commonly used in resistance welding, including single-phase AC, single-phase DC, three-phase DC, and MFDC Magnesium welding in terms of cracking and expulsion The effect of individual welding parameters 2-D and 3-D lobe diagrams New materials for the ultrasonic evaluation of welds, including A-scan, B-scan, and in-line A-scan The book begins with chapters on the metallurgical processes in resistance spot welding, the basics of welding schedule selection, and cracking in the nugget and heat-affected zone of alloys. The next several chapters discuss commonly conducted mechanical tests, the monitoring and control of a welding process, and the destructive and nondestructive evaluation of weld quality. The authors then analyze the mechanisms of expulsion—a process largely responsible for defect formation and other unwanted features—and explore an often overlooked topic in resistance welding-related research: the influence of mechanical aspects of welding machines. The final chapters explain how to numerically simulate a resistance welding process and apply statistical design and analysis approaches to welding research. To obtain a broad understanding of this area, readers previously had to scour large quantities of research on resistance welding and essential related subjects, such as statistical analysis. This book collects the necessary information in one source for students, researchers, and practitioners in the sheet metal industry. It thoroughly reviews state-of-the-art results in resistance welding research and gives you a solid foundation for solving practical problems in a scientific and systematic manner.

The early chapters of this book provide thorough coverage of resistance spot welding fundamentals and principles. Topics covered include lobe and current range curves, contact resistance vs. electrode force, dynamic resistance, heat balance, nugget growth, etc. Equipment issues such as machine types, power supplies, and electrodes are addressed. Subsequent chapters focus on specific spot welding challenges to modern automotive manufacturing. Approaches to welding modern materials including advanced high-strength steels, coated steels, and aluminum alloys are covered in much detail. The final chapters focus on many common production and quality control issues, such as electrode wear, monitoring and testing, computational modeling, and welding codes. The overall goal of the book is to provide a comprehensive resource for automotive engineers and technicians who work with modern spot welding equipment and automotive materials.

The book begins with thorough coverage of Resistance Spot Welding fundamentals and principles, including concepts such as Lobe Curves, contact resistance vs. electrode force, dynamic resistance, heat balance challenges, nugget growth, machine types and power supplies, and electrodes. Subsequent chapters address challenges and approaches to important topics of welding advanced high-strength steels, such as DP, TRIP, TWIP, and Press Hardening Steel, as well as aluminum alloys. Welding issues associated with the various coatings used on these steels are addressed. The final chapters are dedicated to weld quality, monitoring, testing, computational modeling, and common automotive production issues such as the welding of multiple sheet stack-ups and a brief overview of associated codes and standards. The second edition includes updated chapters and additional information, such as expanded information on welding aluminum to steel, a new section on alternative welding and joining methods, and updates on monitoring and control as well as welding issues associated with the latest advanced high-strength steels.