Simultaneous improvements in strength and ductility of as-extruded Mg-1.0Sn-0.5Zn alloy via Ce addition in combination with pre-twining deformation

Abstract

In the present study, the comprehensive effects of Ce addition and pre-twining deformation on the microstructure evolution and mechanical properties of Mg-1.0Sn-0.5Zn alloys were systematically investigated. After Ce addition, two phases (CeMgSn and CeMgZn2) were newly emerged, which eventually hampered grain growth and postponed {10−12} tensile twin extinction during annealing subsequent to pre-compression. Besides, due to prominent grain refinement, the addition of Ce into as-extruded Mg-Sn-Zn alloy gave rise to a noticeable improvement in strength. As for the application of pre-twining deformation, it could induce a significant increase in the tensile ductility via texture tailoring, and the relative Visco-Plastic Self-Consistent (VPSC) simulation confirmed that the main reason was attributed to the vigorous activation of {10−12} tensile twins. As a result, both the strength and ductility of the as-extruded Mg-Sn-Zn alloy were substantially improved via the combination of Ce addition (obvious grain refinement) and pre-twining deformation (effective texture regulation).