Numerical Computation of Anisotropically Evolving Yield Surfaces Based on Micro-to-Macro Transitions

Abstract

The paper proposes a numerical computation technique for anisotropically evolving yield surfaces based on micro–to–macro transitions. The underlying model of the finite crystal plasticity and the homogenization approach have previously been formulated by Mieheet al. [2]. The technique proposed has the following two central aspects, firstly a criterion for the determination of the macroscopic yield point is introduced which is based on the physically relevant mechanisms on the microscale and secondly, as a key point of the methodology, total unloading is applied to the representative volume element (RVE) before the yield surface for the corresponding microstructure is determined. The explained method is applied to a Taylor type polycrystalline material model. With respect to the validation of the proposed concept different tests are performed for various preloading conditions and comparisons with experimental findings are provided. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)