Download or read book Development of Appropriate Spot Welding Practice for Advanced High Strength Steels TRP 0114 written by Jerry Gould and published by . This book was released on 2004 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: This program evaluated the effects of common manufacturing variables on spike-tempering effectiveness. The investigation used design-of-experiment (DOE) techniques, and examined both dual-phase and martensitic grades of high-strength steels (HSS). The specific grades chosen for this project were: Dual-phase (DP) 600, galvannealed (GA), 1.55 mm (DP) 600; Dual-phase (DP) 980 (uncoated), 1.55 mm (DP) 980; and Martensitic (M) 1300, 1.55 mm (M) 1300. Common manufacturing conditions of interest included tempering practice (quench and temper time), button size, simulated part fitup (sheet angular misalignment and fitup), and electrode wear (increased electrode face diameter). All of these conditions were evaluated against mechanical performance (static and dynamic tensile shear). Weld hardness data was also used to examine correlations between mechanical performance and the degree of tempering. Mechanical performance data was used to develop empirical models. The models were used to examine the robustness of weld strength and toughness to the selected processing conditions. This was done using standard EWI techniques. Graphical representations of robustness were then coupled with metallographic data to relate mechanical properties to the effectiveness of spike tempering. Mechanical properties for all three materials were relatively robust to variation in tempering. Major deviations in mechanical properties were caused by degradation of the weld itself. This was supported by a lack of correlation between hardness data and mechanical results. Small button sizes and large electrode face diameters (worn electrodes) produced large reductions in both static and dynamic strength levels when compared to standard production setups. Dynamic strength was further degraded by edge-located welds.
Download or read book 108 1 Hearings Department of The Interior and Related Agencies Appropriations For 2004 Part 5 2003 written by and published by . This book was released on 2003 with total page 992 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of the Interior and Related Agencies Appropriations for 2004 Testimony of Members of Congress written by United States. Congress. House. Committee on Appropriations. Subcommittee on Department of the Interior and Related Agencies and published by . This book was released on 2003 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of the Interior and Related Agencies Appropriations for Fiscal Year 2004 written by United States. Congress. Senate. Committee on Appropriations. Subcommittee on the Department of the Interior and Related Agencies and published by . This book was released on 2003 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of the Interior and Related Agencies Appropriations for written by United States. Congress. Senate. Committee on Appropriations and published by . This book was released on 2004 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Department of the Interior and related agencies appropriations for 2004 written by United States. Congress. House. Committee on Appropriations. Subcommittee on Department of the Interior and Related Agencies and published by . This book was released on 2003 with total page 1006 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 108 1 Senate Hearings Department of the Interior and Related Agencies Appropriations For Fiscal Year 2004 S Hrg 108 203 March 20 2003 written by and published by . This book was released on 2004 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resistance Spot Welding written by Menachem Kimchi and published by Springer Nature. This book was released on 2023-04-23 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book The Joining of Advanced High Strength Steels Using Resistance Spot Welding written by Christopher Carl Edward Miller and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resistance Spot Welding of Advanced High Strength Steels written by and published by . This book was released on 2019 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resistance Spot Welding written by Menachem Kimchi and published by Springer Nature. This book was released on 2022-05-31 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book Resistance Spot Welding of Advanced High Strenght Steels written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spot Welding of Advanced High Strength Steels AHSS written by Mohammad Ibraheem Khan and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Surface Condition on Resistance Spot Welding of Advanced High Strength Steel written by Xu Han and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced high strength automotive sheet steel (AHSS) is used in body-in-white design to reduce vehicle weight while maintaining high crashworthiness. Surface coatings applied to AHSS to protect it from oxidation and decarburization during its processing and life cycle. Due to the characteristics of AHSS, including alloying content and thermal process requirements, a variation of final surface conditions is possible. The resistance welding process is affected by surface changes as it alters the electrical contact resistance. As a result, a change in resistance spot welding process window occurs. Without proper attention, this variation in the operation window could reduce the joint strength and results in an unpredictable failure by having an undersized nugget. In this study, two surface-related phenomena, internal oxidation, and zinc diffusion, were investigated to characterize their impact on resistance spot welding. Additionally, a heat input based electrical dynamic resistance approach was proposed to determine appropriate welding current given variations in the Zn diffusion layer resulting from heat treating during this hot stamping process for PHS steels. Promotion of internal oxidation is used in Zn galvanizing line to improve the wettability of the steel surface to the Zn pool via the enhancement of the reactive wetting. The presence of these internal oxides has shown to shift the weld lobe to higher currents, increasing the time required to generate an acceptable weld. Study of weld development showed that surface melting is responsible for this shift in the weld process window. The surface melting created a liquid contact surface between the faying surface, which reduced the electric contact resistance and heat generation at the weld faying surface. A smaller nugget was formed due to the reduction of heating. To compensate for this reduced heat generation, a higher welding current was required when RSW of internally oxidized samples. Zinc diffusion from the galvannealed coating to the steel substrate occurs when a galvannealed steel was exposed to elevated temperature during heat treatment in the press-hardening process. This formed a Fe-Zn diffusion layer. The thickness and composition of the diffusion layer were found to be dependent on heat-treatment conditions. With an increase in heat-treatment time, the electrical resistance of the steel sheet was observed to increase as well. With higher electrical resistance, less welding current was needed to weld the material. While a change in nugget size occurred when welding steels made using different heat-treatment conditions with constant welding parameters, the mechanical lap shear strength was not impacted. Martensite tempering in the heat-affected region was more severe in samples with a larger diameter weld nugget, which decreased the required stress for failure to occur, counter-acting the increase in strength gained from the larger nugget size. This work has shown that with a heat-treatment time ranging between 4 to 10 minutes, a robust resistance welding schedule can be determined to generate a mechanically sound weld. Dynamic electrical resistance has been used to monitor the weld quality. Heat input analysis was shown to reflect the weld development as it takes into account the full weld cycle. Heat input has shown to have a linear correlation with nugget size. Undersized nugget can be successfully detected and corrected by changing the welding current based on the heat input value calculated from dynamic resistance measurement.
Download or read book Resistance Spot Welding of Low Carbon and High Strength Steels written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Properties of Resistance Spot Welds in High Strength Steels written by Neil Stevenson and published by . This book was released on 1984 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Liquid Metal Embrittlement of Advanced High Strength Steels During Resistance Spot Welding written by Julian Frei and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
