Numerical simulation of sheet metal stamping by using ODF data

An elasto-polycrystalline plastic finite element method is developed to simulate the deformation behavior and corresponding crystallographic texture evolution of sheet metals in stamping processes. A rate-independent crystal plasticity model and a degenerated shell element are introduced into the explicit finite element formulation. A successive integration method by which the shear rates on the slip systems can be calculated without prior determination of active/non-active state of the slip systems, as generally done in rate-dependent models, is employed to calculate the plastic strain rate of a crystal during the deformation. Representative crystal orientations are extracted from the orientation distribution function (ODF) data and assigned to the integration points of elements according to the distributional characteristic of crystal orientations. The macroscopic stress of a polycrystalline aggregate is evaluated by a volume-averaged response of the representative crystals. Two drawing processes are simulated, one with a cylindrical punch and the other with a square punch. Good agreements between the calculated results and experimental ones are obtained.