Effect of current and welding time on tensile-peel strength of resistance spot welded TWIP 1000 and martensitic steels

摘要

Recently, to reduce car weight for saving fuel, reducing gas emissions, and to raise car safety by selecting the optimum material that meets desired mechanical properties, Advanced High Strength Steels (AHSS) have been continuously in development. TWinning Induced Plasticity (TWIP) steels, that have high tensile strength with high elongation, and Martensitic steels, which tensile strengths can be raised up to 1700 Mpa, are among the most significant members of AHSS. However, strength of joints as important as the material itself. In an automotive body, the most practiced joining method is resistance spot welding. Tensile-peel test in resistance spot welding is of high importance, because its behavior akin to the breaking action of the sheet metal at the time of the accidents. In this study, tensile-peel strengths are investigated in terms of current and weld time using resistance spot welding. The weld time range is selected between 5-30 periods (a period 0,02 sec) with 5 period increments.