ON MULTIPLE SPINS AND TEXTURE DEVELOPMENT - CASE-STUDY - KINEMATIC AND ORTHOTROPIC HARDENING

A general constitutive formulation for large inelastic deformations is presented, employing multiple constitutive and plastic spins in the rate equations of evolution for the tensorial internal variables. The multiplicity of the spins enables the macroscopic description of complex texture development, by allowing differential orientations of the internal variables in the course of deformation. The general case is illustrated by the study of a combined kinematic/orthotropic hardening model. The study is focused on the orientational evolution of the back-stress and, in particular, the orthotropic directions, in what can be called orthotropic texture development. Use of macroscopic and continuum micromechanical models provides interesting results on the texture development in simple shear, expressed by the variation of the plastic spin. The results are compared with available simulations by a Taylor-type polycrystalline model.