Estimation of the size of the RVE for isotropic copper polycrystals by using elastic-plastic finite element homogenisation

The representative volume element (RVE) plays an important role in predicting effective physical properties of random heterogeneous materials. In the present paper, the number of grains needed in a RVE is evaluated for isotropic polycrystalline copper with random texture, by studying dispersion of effective mechanical response of crystalline aggregates of various sizes extracted at various positions in a representative volume. For each extracted aggregate, finite element method (FEM) was used to simulate tensile test in order to calculate effective stress needed to strain the aggregate up to 1% and 2%. Both two- and three-dimensional polycrystalline aggregate models have been studied. The main result is that for the same accuracy the size of RVE is close to the ones available in the literature and which were calculated for elastic polycrystals. Finally, the influence of the reached value of strain and the tensile test strain rate on the RVE size has been analysed. (C) 2009 Elsevier B.V. All rights reserved.