An Insight into Microstructure and Mechanical Response of Mg-Li-Based Composites Prepared Using Glass Microballoons as Starting Reinforcement

Magnesium-lithium (Mg-Li) alloys are emerging lightweight materials that can find applications in the aerospace, automobile, and electronics fields. However, the widespread use of Mg-Li alloys is limited due to their low strength and processing challenges via metal casting due to the unpredictable loss of lithium by oxidation. That said, adding micron-sized high-strength hollow spherical glass microballoon (GMB) particles can improve the mechanical and damping response of Mg and its alloys, besides reducing the density. In the current study, Mg-Li syntactic foams reinforced with GMB particles were reported for the first time. Magnesium-lithium-based syntactic foams of density 1.45-1.66 g/cc were synthesized via disintegrated melt deposition technique and hot extrusion. The effect of GMB reinforcement on the mechanical, thermal, and damping characteristics of lightweight Mg-Li alloy is studied. The developed Mg-Li/GMB composites displayed improvements in the mechanical and damping response while maintaining an ~ 12% lower density than Mg. Microstructure-property correlations of the developed composites are discussed.