Effect of Extrusion Ratio on Microstructure and Mechanical Properties of As-cast AZ91D Magnesium Alloy

摘要

In order to study the effect of deformation extent on microstructure and mechanical properties of as-cast AZ91D magnesium alloy, experiments of direct extrusion were performed at temperature of 420°C and different extrusion ratios. The microstructure and mechanical properties of billets and extrudates were measured. Experimental results show that the grain size of as-cast AZ91D magnesium alloy can be dramatically refined by extrusion. Direct extrusion can obviously improve the mechanical properties of as-cast AZ91D magnesium Alloy, comparing with the pre-extruded billet, the tensile strength, yield strength and elongation of extrudate can be improved by at least 83%, 154% and 150% respectively. As the extrusion ratio increases, the tensile strength and yield strength of extrudate will increase at first and then fall.