Assessment of resistance spot welding parameters on the strength and reliability of AISI 316L stainless steel joints

This study investigates how resistance spot welding parameters affect the joint strength and reliability of AISI 316L stainless steel, examining the effects of welding current, welding time, electrode pressure, and holding time. A 2ᵏ full factorial design combined with Weibull analysis was employed to systematically evaluate the influence of each parameter. Results indicate that the optimal welding conditions—4.0 kA welding current, 0.5 s welding time, 0.3 MPa electrode pressure, and 5.0 s holding time—lead to superior joint strength and reliability, achieving an average tensile shear force of 2376.02 N. Examination of the welded specimens revealed a pull-out failure mode and ductile fracture. Unlike previous studies that primarily focused on maximizing strength, this research integrates both strength and reliability assessments, providing a more comprehensive evaluation. The Weibull analysis not only validates findings from conventional analysis of variance, but also provides additional insights into joint reliability, demonstrating an effective alternative methodology for optimizing welding parameters. GRAPHICAL ABSTRACT HIGHLIGHTS A full factorial design combined with Weibull analysis was utilized to evaluate the effects of resistance spot welding parameters on AISI 316L stainless steel joints. High welding current, short welding time, low electrode pressure, and long holding time were identified as optimal conditions for achieving superior joint strength and reliability. Weibull analysis provided additional insight beyond ANOVA, enabling simultaneous assessment of strength and reliability, and guiding improved parameter selection for reliable welding.