Optimization of Initial Blank Shape for Minimizing the Trimming Process in Hot Stamping of T-Shaped Parts

Abstract

Blank optimization in stamping is a way to reduce the cost of unnecessary material consumption or subsequent trimming operations by acquiring the final target part in a single forming process. There have been many studies on blank optimization in room temperature stamping, but few studies have yet been conducted in hot stamping. In this study, a blank shape optimization was conducted for a T-shaped part simulating a body center pillar. A finite element analysis (FEA) for the hot stamping process was performed using an appropriately assumed initial blank shape, and the blank shape was updated based on the shape error between the outline of the deformed blank obtained from the FEA and that of the target part. The shape error was calculated by applying the modified radius vector method. Hot stamping test was carried out using the optimal shaped blank predicted by the FEA. It was confirmed that the outline of the deformed blank obtained by the actual test was very close to the outline of the target part. From the results of this study, it can be seen that the blank optimum design technique at room temperature stamping can be applied to the case in hot stamping.