Effect of Heat Treatment on Microstructures and Properties of Mg-9Gd-4Y-0.3Zr Alloy

microstructures, aging hardness, mechanical properties of Mg-9Gd-4Y-0.3Zr alloys were investigated. The microstructure is a typical dendritic structure of as-cast sample, The aging test of extruded samples were carried at a temperature rang of 200-300°C and at a different aging time. The aging peak hardness is about 120HV, tensile strength was tested at temperature 25°C, 200°C, 250°C and 300°C, tensile strengths are 375 Mpa, 364 Mpa, 329 Mpa, 286 Mpa respectively, the maximum elongation is 13.32% at 300°C. The fracture mode is mainly microvoid coalescence fracture combination the brittle cleavage fracture at room temperature, and microvoid coalescence fracture at 200-300°C.