Understanding the basal texture initiation in a randomly-oriented AZ31B alloy during cold-rolling

Abstract

This study experimentally investigated basal texture initiation and development during cold rolling, in combination with simulation using a modified visco-plastic self-consistent (VPSC) model. The results showed that the orientation of extension twins exhibit a random distribution after rolling. In contrast, the matrix grains deformed by slips tend to orientate with their c-axis around the normal direction (ND). Plastic strain concentration induced by dislocation piling up at grain boundaries contributes to plastic deformation inhomogeneity, and promotes the basal–pyramidal and prismatic–prismatic binary slips. Incorporated with the interactions between the basal 〈a〉 and pyramidal 〈c + a〉 dislocations, and between the prismatic 〈a〉 dislocations, the VPSC model replicates the experimental results, effectively demonstrating the process of the basal texture initiation and development. The basal texture initiation is independent of twinning, and results mainly from the development of misorientation induced by the formation of dislocation sub-boundaries via the interaction between the basal 〈a〉 and pyramidal 〈c + a〉 dislocations.

Keywords

• Generalized Schmid factor (G-SF)
• Deformation modes
• Texture initiation
• Dislocation interaction
• Modified VPSC model