Polycrystal plasticity modeling of intracrystalline boundary textures

A finite element formulation is used to simulate and study the deformation response of face-centered cubic polycrystals. The polycrystals consist of r hombic dodecahedral-shaped crystals, each finely discretized with tetrahedr al elements. Rhombic dodecahedra are twelve-sided, regular, space-filling p olyhedra that are used to represent a microstructure with equiaxed grains. Material behavior is based on rate-dependent, crystallographic slip on a re stricted number of slip systems. The numerical formulation maintains compat ibility and equilibrium under the application of applied loads using an ass umed-stress hybrid finite element methodology. Spatial variations in deform ation arise in the polycrystal even under simple external loadings and lead to grain subdivision characterized by the formation of;boundaries separati ng regions with differing lattice orientation. Particular attention is focu sed on the resulting crystallographic misorientation across these boundarie s and their orientations relative to the applied loads. This evolving intra grain boundary texture is compared to published experimental data obtained using TEM and Kikuchi pattern analysis. (C) 1999 Acta Metallurgica Inc. Pub lished by Elsevier Science Ltd All rights reserved.