| Abstract Scope |
Alloying elements improve the low-temperature formability of magnesium (Mg) by reducing the critical resolved shear stress and c/a axial ratio. While Mg-Li alloys exhibit distinct crystal structures based on lithium content, they suffer from a softening phenomenon caused by grain coarsening of the β-Li phase. This study systematically investigates the effects of Al addition and various heat treatment temperatures and durations on the microstructure and mechanical properties in the β-Li region of Mg-9.5Li-1.2Zn-xAl (x = 0, 0.5, 1, 1.5, 2 wt.%) alloys. The alloy specimens were melted under an SF6 + CO2 gas atmosphere, cast into a mold preheated to 200 °C, and directly extruded into 4 mm thick sheets. Following homogenization at 450 °C for 2 hours, the samples underwent diverse heat treatments. Microstructure, phase evolutions, and room-temperature mechanical properties were comprehensively evaluated using OM, SEM, XRD, and micro-Vickers hardness tests. |