Structure-Mechanical Properties Relationship in Resistance Spot Welding of AISI304 Austenitic Stainless Steel

This paper aims at investigating on the influence of welding current on the quality of AISI304 resistance spot welds. Mechanical properties of the spot welds (peak load, failure energy and failure mode) were evaluated using tensile-shear test. The relationships among welding current, weld fusion zone characteristics and failure behavior were studied. Generally, it was observed that increasing fusion zone size is accompanied by an increase in load carrying capacity and energy absorption capability. However, when expulsion occurs, despite of almost constant weld fusion zone size, energy absorption capability reduces significantly due to increase in electrode indentation depth. Considering the failure mechanism in the tensile-shear test, minimum required fusion zone size to ensure the pullout failure mode was estimated using an analytical model.