Abstract
It has been reported that the weldability of the spot weld joint with initial gap is strongly influenced by the contact between electrode and plate. The state of contact during the welding largely depends on the deformation in the squeezing process. On the other hand, the characteristics of the deformation change with the geometry of the joint and the material property. Thus, the authors analyzed the deformation under squeezing process by the Finite Element Method to clarify the effects of geometry and material properties. Based on the numerical analyses, the squeezing process is shown to be divided into three stages with respect to plastic deformation and large deformation. Further, to predict the electrode force required to close the initial gap, two methods, using parametric curves and approximatin curves respectively, are proposed.
