Clinching with divided punch to prevent critical neck thicknesses

Abstract. Clinching thin sheet metal into a thicker part can result in low neck thicknesses or even cracks. How these critical values for thickness be counteracted is described this paper, using two-part punch, which devided an inner and outer unit. At the beginning, both move parallel direction of die until punch stops at defined position only one moves further down forms clinch point, with its characteristic contour geometric interlock thickness. Due to large diameter beginning process, more material initially flows area than conventional clinching, so that greater achieved. Numerical simulation was used create concept verify it experimentally. The has positive effect on shear tensile strength also transferred typical joining clinching (thick material).