Texture adjustment approach of magnesium alloys via variable strain path calculated by an integrated finite element-viscoplastic self-consistent model

Abstract

An integrated calculated approach based on weakly coupled finite element (FEM)-viscoplastic self-consistent (VPSC) model was established to simulate the texture evolution during the variable strain path extrusion process of magnesium alloys. The spiral die extrusion (SDE) process with additional circumferential shear deformation was applied to investigate the effect of path control on texture adjustment and verify the accuracy of the model. The results indicated that the additional spiral shear resulting from the overall inclined flow path effectively reduced the intensity of the {0002}//ED fiber texture by suppressing basal slip activation in the core area, while the local shear deformation along the spiral equal channel strain path led to the formation of an inclined {0002}//ND plane texture on the side. Using the modified Hall–Petch relationship, the correlation between texture and yield strength was quantified. Specifically, the weakening of the texture effectively suppressed {10–12} tensile twinning, which compensated for the deficiency of compressive yield strength without significantly sacrificing tensile yield strength, and thus improved the tension-compression asymmetry. Furthermore, the strongly inclined {0002}//ND plane texture inhibited the widespread activation of basal slip during tensile yielding, thereby enhancing the yield strength.