EFFECT OF ANNEALING ON THE MICROSTRUCTURE AND MECHANICAL PROPERTIES OF RESISTANCE SPOT WELDED -SUS316L

The aim of the study is to improvise mechanical properties-tensile strength and microstructure behaviour of the material when the Resistance Spot Welding (RSW) is used to combine two metal-stainless steel (SUS316L). Constant nugget diameter needs to be maintained; thus, the constant parameter is needed by setting up 2.5 kN load with 5 kA 25 cycle as an optimum parameter. However, RSW the material absorbs high volumes of energy; hence it causes the material properties retarded. Therefore, post heat treatment (annealing) is used to treat the heat-affected zone of the welded diameter by manipulating the temperature of heat-treated, holding time and the heat rate. Tensile and microstructure tests are conducted to investigate the effectiveness of treatment analysis. It is found that annealing heat treatment improves the ductility of the material.Keywords: Resistance Spot Welded (RSW), stainless steel (SUS316L), heat affected zone, annealing, tensile load, Design of Experiments (DOE), Respond Surface Method (RSM)