Mechanical and microstructural characterization of resistance spot welded dissimilar TWIP1000/TRIP800 joints

Abstract

Abstract In this work, resistance spot weldability of dissimilar TWIP1000/TRIP800 joint was investigated in terms of microstructural and mechanical characterization. The maximum tensile-shear load bearing capacity was 16,918 N in 6 kA welding current with 30 cycles of welding duration. Pull-out failure which was dominant and interfacial failure modes were obtained in tensile-shear tests. Although heat affected zone of the TRIP steel was totally transformed into tempered martensite, it showed better separation performance than TWIP steel. Heat affected zone of the TWIP steel was narrow, secondary phase formations and sudden grain coarsening have compromised the weakest point in the resistance spot welded joint.