Numerical investigation of piercing of DP600 within a critical range of slant angle

Abstract

Deep drawn parts often have complex designs and must therefore be trimmed or punched in a subsequent stage. Due to the complex part geometry, most punching areas have a critical slant angle (angle between part surface and ram movement direction) which differs from the vertical direction. Such piercing within the critical range of the slant angle may lead to severe damage of the cutting tool due to bending effects on the cutting punch. Consequently, expensive cam units are required to transform the ram movement direction in order to perform the piercing process perpendicularly to the local part surface. However, the critical angle of attack described above has not yet been sufficiently investigated for modern sheet metal materials. The purpose of this study is to investigate the influencing factors and their effect on lateral punch deflection during piercing of high strength steel DP600 with slant angles using the FEM Software DEFORM 3D and to create a simulation model that enables a previously sophisticated simulation of the shearing process at different cutting angles. The aim of the study was to measure the lateral deviation of the punch when cutting with a slant angle. The calculated results show that the horizontal deviation is mainly influenced by the slant angle of the workpiece surface, the cutting line and the length of the punch.