Strain Hardening Analysis of SUS 304 Stainless Steel Cup for Multi Stage Deep Drawing Using Finite Element Simulation Comparison with Experiment Result

This work aims at the numerical investigation on the multi-stage deep drawing method of cup from SUS 304 stainless steel sheet thickness 0.8 mm. In order to reveal strain-hardening characteristics in each stage and reduce the stage forming. The elasto-plastic finite-element analysis was used for determining the stress, strain, and strain flow of multi-stage deep drawing cup of SUS304. The plastic flow behavior used in this work was obtained from the tensile test under uniaxial state. The effective strain and percentage in thinning distributions were examined from both of the finite-element analysis and experiments. Strain hardening exponent values of each stages are determined by using uniaxial tensile test. Form this study, the simulation results are good agreement with the experimental results. The increased tensile strength were reduced the strain quantities in every stage and a proper strain hardening plays an important rule to the formability. Especially, the increased strain hardening with respect to insufficient die movement or excessive pressure of bank holder force will affect the failure modes.