Analysis of texture evolution in magnesium during equal channel angular extrusion

Texture development in magnesium during equal channel angular extrusion (ECAE) with an angle of 90° between the intersecting channels has been studied. Textures were simulated using polycrystal plasticity models as well as determined experimentally for routes A, Bc and C up to four passes. Based on a previous study on texture evolution during the simple shear of materials with hexagonal crystal structures [Beausir B, Tóth LS, Neale KW. Acta Mater 2007;2695:2705], the ideal orientations for ECAE of hexagonal metals were identified considering the shear to be at the 45° intersection plane of the two channels. Although dynamic recrystallization (DRX) was experimentally observed during the ECAE experiments, the polycrystal modeling using the viscoplastic self-consistent (VPSC) model was able to reproduce the experimental textures successfully. This was attributed to the fact that the textures were c-type fibers with their axis of rotation parallel to the c-axis, whereas the nucleation of grains during DRX takes place in positions simply rotated around the c-axis.