Effects of welding condition on controlling the residual stress in resistance spot welds

Abstract

This study examines the control of the residual stress in resistance spot welds by controlling the electrode force profile during the holding time. To examine the residual stress, numerical simulations of spot welding were performed. First, the effect of the electrode force value during the holding time on the residual stress distribution was investigated. The results show that an increase in the value of the electrode force tends to reduce the tensile residual stress. Second, the effect of the time duration of the applied electrode force on the residual stress distribution was investigated. The results show that it is important to apply the electrode force during the transformation to reduce the tensile stress. Finally, as an example, a controlling electrode force profile was proposed that reduces the tensile residual stresses in spot welds. The results indicate that the residual stresses in the spot welds can be reduced by increasing the electrode force during cooling and by applying the electrode force during the transformation.