Microstructure, Mechanical and Corrosion Properties of Resistance Spot Welded 316 Stainless Steel Joints: The Effect of Welding Current

In this study, resistance spot welding (RSW) of 316 stainless steel has been studied, focusing on the welding current (10, 15, and 18 kA) and its impact on the microstructure, mechanical, and corrosion properties. The laboratory verification of welding joints has been achieved by studying the mechanical behavior of welded joints using the tensile–shear tests. Microstructure examination has been done using optical microscopy (OM), surface morphology characterization using scanning electron microscopy (SEM). The corrosion behavior of weld joints has been studied using a potentiodynamic polarization (PD) technique in a 3.5 wt. % NaCl solution. Evaluation of the welded joints indicated that corrosion resistance of RSW joint at 15 kA welding current is higher than that of other joints, whereas the corrosion rate of RSW joint at 10 kA welding current is less than that of RSW joint at 18 kA welding current. In the presence of ferrite phase, mechanical and corrosion properties improved.