Modeling the effect of strain reversal on grain refinement and crystallographic texture during simple shear extrusion

This paper is concerned with the modeling of the effect of strain reversal on crystallographic texture and microstructure evolution in simple shear extrusion (SSE) processing of commercial purity copper. To reach this goal, the evolution of microstructure is predicted by a dislocation density-based constitutive model in which the effect of strain reversal is considered. This dislocation-based model is embedded in a crystal plasticity finite element (CPFE) model. In FE models, a representative volume element of the polycrystal at the central region of the billet is subjected to deformation history experienced by the SSE process with backpressure. By comparison the predicted crystallographic texture with the published data, it is concluded that the CPFEM well predicts a simple shear texture after a complete pass. The predicted results show 5-10% increase in the rate of dynamic recovery of the second half of deformation zone in comparison with the first half. The modified dislocation-based model predicts that the cell size of a complete pass is more than that of 0.5 pass sample as much as 27%.