Evaluation of forming quality and spring-back of fuel cell metallic bipolar plate during stamping via simulations

This research studies the effects of mold design parameters on stamping of fuel cell metallic bipolar plate (MBP). The Taguchi method is used as the theoretical basis of the mold design optimization, and a simulation is carried out using the Deform 3D software. The optimal mold design parameters in critical locations where defects might occur are derived for micro-level simulations. The thinning ratio and damage are compared with different combinations of several parameters, such as fillet radius, channel depth, round corner radius, channel width, rib width, draft angle, frictional coefficient and punch velocity. The first three parameters are more significant in affecting the micro-level quality of MBP than the others, with the fillet radius of being the most important. Dynaform is also used to simulate the forming properties of macro-level mold design, while a forming limit diagram is used to analyze the forming quality of the design pattern, and spring-back is simulated to predict the warpage of the sheet. The MBP is stamped using the optimal parameters, and the forming results are compared to those from the simulations. The use of two simulation methods with the Taguchi method is proved produce results that are very similar to the experimental ones.