Effect of grain refinement of magnesium alloy AZ31 by severe plastic deformation on material characteristics

This work was focused on the grain refinement of magnesium alloy AZ31 by the equal channel angular pressing (ECAP) and investigation its effect on the microstructural change and mechanical properties. From the experimental works, it was observed that the fine and equiaxed grains with less than 3.0 μm were achieved. It was also found out that the decreasing temperature gave the finer grain and higher microhardness. In addition, in order to find the effect of grain size on the mechanical properties, tensile tests were carried out to analyze the changes in the yield and tensile strength and fracture elongation. From tensile tests, the fracture elongation increased with decreasing grain size, while the yield and tensile strength decreased. Finally, a forged impeller using grain refined magnesium alloy at the optimal processing condition was shown.