Microstructure and mechanical properties of YAl2 reinforced MgLiAl composite

MgLiAl matrix composite reinforced with YAl2 intermetallics particles were developed by stir-casting. Microstructure features of the YAl2/MgLiAl composite were investigated. The results show that a good particle distribution and interfacial bonding are obtained. There are no reaction products at particle/matrix interface. YAl2p/Mg-Li-Al composites have excellent comprehensive mechanical properties. The tensile strength and yield strength are significantly improved by the addition of YAl2 particulates, while a good ductility property is kept. At room temperature, tensile strength, yield strength and elongation of 20%YAl2p/Mg-Li-Al composite are 225, 161.4 MPa and 9% respectively. The addition of YAl2 particulates improves the deformation resistance at high temperature of the magnesium-lithium based composites, which makes the composites have good mechanical properties at high temperature. At 180 deg. C, the tensile strength and yield strength of 20%YAl2p/Mg-Li-Al composite are 78, 57 MPa respectively, and increase over past 100% and 200% than that of matrix alloy.