The effect of material and process variables on the stamping formability of sheet materials

To investigate the effect of material and process variables on the stamping formability of sheet materials, simulations of cup drawing and the Yoshida buckling test were carried out using ABAQUS, a commercial finite-element analysis code. The effects of various factors on the stamping formability of sheet materials were analyzed by experiments designed according to the orthogonal array of the Taguchi method. Cup-drawing simulation showed that local necking is very sensitive to the plastic-anisotropy parameter of the sheet and to the friction coefficient at the sheet and tool interface. Simulation of the Yoshida buckling test clarified that the buckling behaviour of the sheet material is mostly susceptible to the yield stress and the thickness of the sheet. However, the plastic-anisotropy parameter and the strain-hardening index affect moderately the buckling behaviour of steel sheets after the initiation of buckling.