Effect of weld parameters on joint strength of 904L grade steel using resistance spot welding

Experimental investigation on resistance spot welding of 904L super austenitic stainless steel, which is finding its considerable applicability in automobile sector, is presented in this work. However, joining of this material involves difficulties due to complex working range of process parameters leading to critical mechanical and metallurgical changes in the weld joint. More focus is given on effect of important process parameters like weld time, current, electrode pressure and squeeze time on strength of weld joint. A mathematical model is proposed to understand the combined effect of multiple processing parameters on tensile shear strength (TSS) which can be beneficial to scientific community to get enhanced results. For the present setup, more significant parameter is electrode pressure followed by other parameters. TSS decreases with increase in electrode pressure up to certain level and then starts increasing while TSS increases with increase in squeeze time and subsequently it remains constant.