MICROSTRUCTURE AND MECHANICAL-PROPERTIES OF BULK MG70CA10AL20 ALLOYS PRODUCED BY EXTRUSION OF ATOMIZED AMORPHOUS POWDERS

The application of high-pressure Ar atomization to Mg70Ca10Al20 alloy causes the formation of amorphous and Mg phases, and subsequent extrusion of the atomized powder at 673 K results in the formation of a bulky alloy with a finely mixed structure consisting of Al2Ca embedded in an Mg matrix. The mixed phase alloy exhibits a high yield strength of 600 MPa, a high specific yield strength of 3.3 MNm kg-1, a high Young's modulus of 49 GPa at room temperature, a high elevated-temperature strength above 300 MPa in the range up to 550 K, and good corrosion resistance; these properties are superior to those of commercial Mg-based alloys. The simultaneous achievement of high mechanical strength and good corrosion resistance is attractive for subsequent development as a new type of high-strength materials.