Cup Deep Drawing Simulation of Commercially Pure Titanium for Varying‐Shoulder‐Radius Die Using Finite Element Method and Non‐associated Flow Rule

To test the ability of predicting earing height in finite element simulations with nonassociated flow rule for complex die configurations such as “varying‐shoulder‐radius die,” a 3D simulation of deep drawing of a commercially pure titanium sheet is conducted. Cup deep drawing experiments with single‐radius die are first conducted to verify the accuracy of the simulation results, and the results are compared with the experimental measurements. Two types of nonassociated flow rules are applied: the Hill‐Hill combination using Hill48 for both the yield function and plastic potential, and the Hill‐Yld combination using Hill48 for the yield function and Yld2004‐18p for the plastic potential. The results show that the Hill‐Yld model reproduces the experimental results well in the range of 45°–90°. Subsequently, deep drawing using varying‐shoulder‐radius dies is simulated, and the results are compared with the experimental measurements. The results of the comparison show that the Hill‐Yld model is able to qualitatively reproduce the experimental trend of the earing height. The results suggest that the Hill‐Yld model with Yld2004‐18p as the plastic potential can qualitatively reproduce the results of deep drawing experiments using varying‐shoulder‐radius dies.