Effects of solution heat treatment on microstructure and mechanical properties of AZ61-0.7Si magnesium alloy

The effects of solution heat treatment on the microstructure and mechanical properties of AZ61-0.7Si magnesium alloy were investigated. The results indicate that the solution heat treatment can modify the Chinese script shaped Mg2Si phases in the AZ61-0.7Si magnesium alloy. After being solutionized at 420 °C for 16-48 h, the morphology of the Mg2Si phases in the AZ61-0.7Si alloy changes from the Chinese script shape to the short pole and block shapes. Accordingly, the tensile and creep properties of the AZ61-0.7Si alloy are improved. After being solutionized at 420 °C for 24 h and followed by aging treatment at 200 °C for 12 h, the heat-treated alloy exhibits relatively high tensile and creep properties than those of the as-cast alloy.