Die-design for high-pressure sheet metal hydroforming by finite element simulations and statistical design of experiments

Innovative manufacturing methods like high pressure sheet metal hydroforming imply advantages for sheet metal parts with a complex geometry compared to conventional deep drawing. Unfortunately, the experience and knowledge in conventional deep drawing and in die design can rarely be transferred to hydroforming operations. New methodologies for process setup need to be developed in order to make the die design more efficient and to shorten trial-and-error loops. In this paper, a new approach of die designing by combining finite element simulations and statistical design of experiments is presented. Statistical models for the prediction of the quality of a formed workpiece provide the basis for the optimization of a given die design. The optimization aims at a die design for which the statistical models predict a failure-free forming process. To develop statistical models, it is necessary to collect data about the forming process. The data are generated in FE-simulations to obtain a fast and cost-efficient method for die designing.