Multi-stage deep drawing process of axis-symmetric extra deep drawing steel cylindrical cup

Abstract

The paper investigates the design and optimization of the multi-stage deep drawing process for the axis-symmetric extra deep drawing (EDD) Steel cup. The geometrical and process parameters are focused on eliminating defects like thinning, thickening, and wrinkling. The explicit analysis is carried out by using a 3-dimensional finite element model to optimize the total number of deep drawing stages. The proposed multi-stage deep drawing process sequences are numerically simulated and the obtained strain distribution is utilized for the generation of forming limit diagram (FLD) for predicting the defects such as thinning and wrinkling. The numerically generated FLD is further validated by using analytical models such as Keeler Brazier and North American deep drawing research group (NADDRG). The obtained results point out that the proposed design process sequences can be implemented successfully without failure. Among both, the optimized design process sequence has better accuracy with less thickness variation compared to the design sequence with a bulge at the bottom.