A new formulation for the elastic-viscoplastic lower bound and intermediate modeling for polycrystalline plasticity

The aim of this work is to propose a simple intermediate model for large elastic-viscoplastic deformations that could predict the copper and brass components as well as the texture transition. We first propose a new formulation of the Sachs (static) model as extension of this model to large elastic-viscoplastic deformations. In light of state variable based modeling, we introduced a one parameter weight function, 0 < phi < 1, to formulate a simple intermediate model. This proposed model combines, in a simple way, both Taylor and Sachs assumptions. In the applications, we concentrate on the plane strain compression test. The results from these models are shown discussed.