Microstructural and mechanical recovery of overburned Mg-Gd-Y-Zn-Zr alloys via controlled thermal reprocessing

This study develops a controlled furnace-cooling method to repair overburned Mg-Gd-Y-Zn-Zr alloys, traditionally considered irreversibly damaged. Slow cooling (0.7℃/min) enables molten grain boundaries to re-solidify into LPSO and RE-rich phases, eliminating defects. The restored alloy outperforms non-overburned counterparts in strength and ductility after extrusion. This breakthrough challenges the irreversibility of overburning and offers a practical industrial strategy to reduce material waste while advancing lightweight magnesium alloys for high-performance applications.