The investigation of mechanical properties of three steel sheets resistance spot welds

In the daily life, we use many products which made of different sheet metals. Resistance spot welding is used to weld two or three sheets that have different thickness and mechanic featured, with lowest deformation and time, by not using additional material. It is important to understand spot-weld microstructure and mechanical properties in order to apply spot welding successfully. In this study, it was aimed to determine the effect of welding time, current, electrode force on tensile shear load, elongation, nugget diameter and indentation depth of triple welded sheet joints by resistance spot welding (FEP05 sheet + FE 600 DP sheet + FEP05 sheet). Using different materials which has different thicknesses, it was made resistance spot welding and was observed tensile strength, elongation, welding diameter, indentation, microstructure and microhardness of welding zones. The thicknesses of FE 600 DP and FEP05 steel sheets were 2 mm and 0.7 mm, respectively. According to results, it was observed that the tensile strength, elongation, welding diameter, indentation were correlated with more than one parameter.