Influence of the Key Process Parameters in Hydrodynamic Deep Drawing Utilizing a Combined Floating and Static Die Cavity

This study focuses on the effects of the key process parameters during a modified hydrodynamic deep drawing utilizing a combined floating and static die cavity (HDDC). A two-stage hydraulic loading path is recommended in the novel process, and each stage of the hydraulic loading path is a linear loading path with an inflection point. The method to evaluate the wrinkle and forming dimension precision of the formed parts is introduced at first. Then, the influence of the key parameters of the two-stage hydraulic loading path as well as the blank holder force on the dimension accuracy and surface quality of the formed parts was studied in detail. The results showed that the influence of the liquid pressure during the second stage is more significant than that in the first stage in hydrodynamic deep drawing utilizing a combined floating and static die cavity. The initial pressure of the second stage and the maximum pressure arriving moment during this stage have a significant impact on the dimensional accuracy of the formed parts, and the smaller initial pressure or the later the maximum pressure of the second stage arrives, the higher the accuracy of the formed part is. Similarly, the influence of the blank holder force in the second stage on the forming accuracy is more significant than that in the first stage.