Effect of {101 ¯ 2} Extension Twins on Microstructure Enhancement of Mg-3Al-1Zn Alloy in Half Channel Angular Extrusion

Abstract

This paper mainly concerns the enhancement of the microstructure and mechanical properties of the Mg-3Al-1Zn rolled sheet alloy in the half channel angular extrusion (HCAE) process, linking with effects of the starting texture and {10 (1) over bar2} extension twin. The initial HCAE specimens are prepared by imposing the c-axis compression of 5% along the rolling direction to the Mg-3Al-1Zn sheet. They were applied in the HCAE process at the forming temperature of 523 K to make the enhanced microstructure named after HCAE-I-t, II, IIIt according to different starting textures. Improved mechanical properties and homogeneous grain structure with enhanced elongation can be achieved by the specific starting texture (HCAE-I-t) rather than the effect of the induced {10 (1) over bar2} extension twins in the initial specimen.