Numerical concepts for rate-independent single crystal plasticity Original Research Article

We provide a new time integration algorithm for rate-independent single crystal plasticity. The algorithm is based on an augmented Lagrangian formulation of the principle of maximum plastic dissipation. It is a synthesis of Lagrangian multiplier and penalty formulations avoiding their drawbacks (active set search, pseudo-inverse and approximate fulfillment of the yield condition respectively). The algorithm is physically motivated and especially provides a clear concept how to determine the set of active slip systems. The method is stable and efficient, several representative numerical examples are shown.