Investigation of the mechanical properties of TRIP 800 steels in electric resistance spot welding

Combining low price, good corrosion properties and mechanical properties in the automotive industry, TRIP 800 steel sheets are mainly used in the automotive industry due to the high percent elongation (about 30%) under plastic strain. Perhaps the most common application of electric resistance spot welding is in the automobile manufacturing industry, where it is used almost universally to weld the sheet metal to form a car. In this study, TRIP 800 steel sheets with a thickness of 1.5 mm were assembled using the electrical resistance spot welding method. Samples were welded using different welding times and different current intensity values and the results were examined. Strength properties and microhardness distributions of electrical resistance spot welded specimens were investigated. Optical microscope and scanning electron microscope (SEM) were used for macro and microstructure examinations. In this study, the microstructure and distributions of microstructure and current density of the transition zone between welded joint region and TRIP 800 steel were investigated.