Investigation of the microstructure and tensile properties of dual-phase steels of different strength levels joined by resistance spot welding

zIn this study, DP600/DP1000 and DP600/DP1200 resistance spot welding processes were performed.Welding applications were carried out at 7 kA constant welding current and 5 different electrode pressures (2,3,4, 5 and 6 Bar).The study focused on microstructural analysis, microhardness and tensile-shear testing.It was found that the welds consisted of 3 distinct regions.The microstructure differed between the regions.The volume fraction of martensite increased in the weld metal.As the electrode pressure decreased, the tensile-shear force increased for both joint types.The failures occurred on the DP600 side.The pullout type failure occurred in all joints.Hardness values increased from base metal to weld metal in all parameters.Bu almada, DP600/DP1000 ve DP600/DP1200 nokta diren kaynak ilemleri gerekletirilmitir. Kaynak uygulamalar 7 kA sabit kaynak akm ve 5 farkl elektrot basncnda (2,3,4, 5 ve 6 Bar) gerekletirilmitir. alma mikroyapsal analiz, mikrosertlik ve ekme-makaslama testlerine odaklanmtr.Kaynaklarn 3 farkl blgeden olutuu tespit edilmitir.Mikroyap, blgeler arasnda farkllk gstermitir.Kaynak metalinde martenzit hacim oran artmtr.Elektrot basnc azaldka ekme-