Analysis of shear deformation by slip and twinning in low and high/medium stacking fault energy fcc metals using the [formula omitted]-model

Abstract

Experimental tests involving shear stresses allow material to be deformed to very high plastic strain by overcoming localization phenomena. The simple shear texture development, which is also common near the surface of rolled parts, is important to study since it is directly connected to the metal anisotropy. Crystal plasticity models are used to simulate large deformation plasticity and texture evolution. The main insufficiency of most existing models is that they are, in certain cases, unable to predict all type of experimentally observed textures as well as texture transitions. In this paper, we show that the polycrystalline ϕ-model can be used to compute simple shear crystallographic texture transition for face-centered cubic metals (fcc) at large strains. This model takes into account the grains interaction effects but without the Eshelby inclusion theory. Predicted results are compared to experimental shear textures for medium stacking fault energy (SFE) metals (i.e. copper) and low SFE metals (i.e. silver). We show that the ϕ-model is able to predict a clear shear texture transition characterizing a range of fcc metals having high/medium to low SFE. The twinning mechanism is included in the ϕ-model in order to improve the predicted shear textures for low SFE metals. The effect of twinning on the ideal shear texture components is shown and is consistent with experimental results from the literature.