Influences of Rare-Earth Y Addition on the Microstructures, Mechanical Properties and Stacking Faults of ZK60 Alloys by Powder Metallurgy

Powder metallurgy and hot-pressing sintering are used to successfully prepare ZK60 and ZK60-3.63Y alloys. The effects of rare-earth Y addition on the texture evolutions, twinning behaviors, and nano-MgZn2 precipitates of ZK60 alloys are thoroughly investigated. In addition, the interactions between twinning behaviors and stacking fault energy are studied. The addition of rare-earth Y reduces the texture intensities of fine evenly equiaxed grains, and more extension twins are easily triggered due to decreasing stacking fault energy. The boundary relationship ratios of the twins reach 20.3%, which is greater than that of the ZK60 alloy. Furthermore, more spindle nano-MgZn2 precipitates are detected, and the strength and ductility of ZK60-3.63Y are improved. This method is efficient for preparing high-performance ZK60 alloys.