A study on process improvements of multi-stage deep-drawing by the finite-element method

Abstract Multi-stage deep-drawing processes, including normal drawing, reverse drawing, and redrawing, to shape the front shell of a master VAC for an automobile have been analyzed sequentially by the use of the rigid-plastic finite-element method, computational results on the punch/die loads and thickness distributions being obtained. The thickness strains were compared with the results of experiments on current drawing processes, good agreement being found. Deep-drawing processes of the redesigned shell to improve the specific strength and stiffness were simulated with the numerical method developed. By varying several process parameters, such as the blank size, the corner radii of the tools, and the clearances, the simulation results showed improvements in reducing the forming loads. Also, forming defects were found during simulation and the appropriate blank size could be verified.