Analysis of pre-pressing contact of rectangular electrode during resistance spot welding

The pre-pressing contact of rectangular electrode during resistance spot welding of stainless steel using finite element method was studied. The physical model was properly simplified on the basis of simulation accuracy and welding technology and a one-quarter three-dimension finite model of rectangular electrode for resistance spot welding was established. The contact pressure distributions of workpiece/workpiece and electrode/workpiece were researched by simulation. The results showed that the contact pressure distributions of workpiece/workpiece and electrode/workpiece were uneven; the stress concentration was found at the electrode corner angles because of the geometrical property of electrode, while the stress concentration was not obvious at the workpiece/workpiece interface. The contact pressure at electrode edges was the highest and decreased gradually around them.