Texture and Mechanical Properties of Mg-3Al-1Zn-0.5Mn-1.5Ca Alloy Produced by Torsion Extrusion

Abstract

Torsion extrusion was carried out on Mg-3Al-1Zn-0.5Mn-1.5Ca (in mass%) alloy (AZ31+1.5Ca alloy). The annealed torsion-extruded AZ31+1.5Ca alloy exhibited higher elongation compared with the annealed extruded AZ31+1.5Ca alloy without torsion. The ductility enhancement was attributed to a unique texture with h10 1 10i direction inclined 30 from the extrusion direction and low pole density. Besides, the annealed torsion-extruded AZ31+1.5Ca alloy exhibited higher strength compared with the annealed torsion-extruded Mg-3Al-1Zn-0.5Mn (in mass%) alloy (AZ31 alloy). In the extruded AZ31+1.5Ca alloy, the fine second phase particles, which contributed to a suppression of the grain growth during extrusion and annealing, were observed. The enhanced strength of the annealed torsion-extruded AZ31+1.5Ca alloy was likely attributed to not only grain refinement but also strengthening by the presence of the second phase particles.

The material flow and texture-weakening mechanism in double-sided friction stir welded Mg alloy

“…However, owing to the hexagonal close-packed (HCP) structure of Mg alloys, poor ductility and weak formability at ambient temperature are inevitable during plastic deformation because of the available slip system shortage [1]. This shortcoming became worse after the thermal-mechanical process like rolling, extrusion, and forging due to the formation of a highly orientated (0001) basal texture [2][3][4][5]. The strong (0001) basal texture would induce the severe local strain concentration at the early stage of deformation, which introduces crack tips and significantly deteriorate the mechanical properties [6][7][8].…”