Multi-stage Inverse Analysis of Elliptic Cup Drawing with the Large Aspect Ratio

Abstract

An inverse finite element approach is employed for robust capability to design the optimum blank shape from the desired final shape with small amount of computing time and effort. For multi-stage deep-drawing processes, numerical analysis is extremely difficult to carry out because of its complexities and convergence problems as well as tremendous computing time. Analysis of elliptic cup drawing with the large aspect ratio is likewise so difficult as to design and describe intermediate die shapes. In this paper, finite element inverse analysis is applied to multi-stage elliptic cup drawing processes to calculate the thickness strain distribution of each intermediate shape. The multi-stage inverse analysis deals with the convergence among intermediate shapes and the corresponding sliding constraint surfaces that are described by the analytic function of merged-arc type surfaces.