Texture evolution in oriented magnesium single crystals processed by equal channel angular pressing

Magnesium single crystals with different initial orientations were processed by single-pass equal channel angular pressing (ECAP) at 503 K. The texture in the crystals after ECAP was investigated by electron backscatter diffraction and compared to texture simulations based on a visco-plastic self-consistent model. The results show that orientation of [0001] and < 10 (1) over bar0 > axes in single crystals with respect to ECAP die geometry significantly influences activation of various deformation modes and resulting texture evolution. Depending on initial orientation, {10 (1) over bar2} twinning represents an important deformation mechanism at the early stages of forming because it causes reorientation of the matrix to orientations suitable for slip activity. Simulations indicate that, in addition to < a > basal slip, there is an activity of < c + a > pyramidal slip in all crystals. The < a > non-basal slip systems (< a > prismatic and < a > pyramidal) were active in crystals containing structure components with [0001] axis parallel to the transverse direction of the ECAP die. Occurrence of this component in resulting texture caused better deformation behavior without crack formation.