An effect of stress relief annealing on the resistance spot welded TRIP steel joint
Hayriye ERTEK EMRE Ramazan KAÇAR
AbstractIn the present study, the commercially available TRIP800 steel having 1.5 mm thickness was joined with resistance spot welding method by using optimum welding parameters which is assessed with developed weld lobe diagram. A group of samples were post weld heat treated (stress relief annealing treatment) at the temperature of 600oC for 30 minutes. The effect of stress relief annealing treatment on the tensile shear load bearing capacity, energy absorption, hardness and microstructure of weldment was investigated so, the relation with microstructure-mechanical properties was determined. The other group of samples was tested as welded condition for sake of comparison. Conclusively, it is believed that stress relief annealing treatment applied for resistance spot welded TRIP800 weldment did not affect to the constituent phases and failure mode of tensile test sample. However, the hardness decreased in the weld nugget and HAZ. Meanwhile, the tensile shear load bearing capacity and energy absorption of weldment affected negatively.