Anisotropic finite plasticity based on structural tensors—different strategies and application to forming simulations

The accuracry of sheet metal forming crucially relies on the quality of the material description which involves the modelling of large strains, elastic and plastic anisotropy as well as different kinds of hardening. In the present contribution we propose a hyperelasticity-based concept using structural tensors. Two formulations have been investigated. The first one uses stress and strain measures of the reference configuration and includes only symmetric internal variables. In contrast to that, the second model lives in the intermediate configuration and requires as such an assumption about the plastic spin. Both approaches are implemented into the finite element method using a novel integration algorithm based on the exponential map to maintain plastic incompressibility.