On the die face design for stamping an automotive engine hood

Abstract

The die face design for stamping an engine hood was examined in the present study using both the finite element analysis and the experimental approach. Since the engine hood is mainly manufactured in the drawing operation, the die addendum design is the key to the success of manufacturing a defect free product. In order to analyze the addendum design, the existing die addendum designs corresponding to those engine hoods were reviewed first and the design parameters were established. The preliminary study was then performed to determine favorable operation conditions including the suitable stamping die angle, blank‐holder surface shape, and die open line. The optimum design for the die addendum face was then investigated with the use of finite element simulations. The effects of the design parameters constructed in the present study on the occurrence of the defects were examined and a systematic design guideline was proposed. In order to validate the proposed die design, the actual stamping tooling was manufactured according to the finite element analysis and the engine hoods were produced. The part shape, thickness distribution, and the stretch at the central region of the production part were compared with those obtained from the finite element simulations. The consistent agreement between the product parts and the simulation results confirms the validity of the design guide proposed in the present study for stamping an engine hood.