Effect of aluminium on microstructure, mechanical property and texture evolution of dual phase Mg-8Li alloy in different processing conditions

Abstract

The present study investigates the possibility of enhancing the strength with ductility of dual-phase magnesium (Mg)-8 lithium (Li) alloy by the combination of alloying addition aluminium (Al) and suitable thermo-mechanical processing. Microstructural evolution, phase analysis and texture studies were performed for Mg-8Li-xAl (x=0, 2,4 and 6) alloys with the help of scanning electron microscopy (SEM) and X-ray diffraction (XRD). It is understood from the texture studies that the addition of Al to the Mg-8Li alloys activates the non-basal slip at room temperature. In turn, it facilitates the recovery process, hence a substantial improvement in plastic deformation after annealing of the alloys is observed. This is attributed to non-basal slip activity at room temperature. The presence of fine intermetallic compounds in the annealed Mg-8Li-xAl (x=4 and 6) alloys leads to the higher ultimate strength (193±7MPa and 267±9MPa) and ductility (20% and 17%), respectively.