Effects of Minor Sr on As-Cast Microstructure and Mechanical Properties of ZA84 Magnesium Alloy

Abstract

The effects of minor Sr additions on the as-cast microstructure and mechanical properties of the ZA84 magnesium alloy were investigated. The results indicate that adding 0.05-0.15 wt.% Sr to the ZA84 alloy does not cause an obvious change in the morphology and distribution of the Mg32(Al,Zn)49 phase. However, the grains of the Sr-containing ZA84 alloys are effectively refined. Among the Sr-containing ZA84 alloys, the grains of the alloy added 0.10 wt.% Sr are relatively finer than other alloys. Furthermore, adding 0.05-0.15 wt.% Sr to the ZA84 alloy improves the tensile properties at room temperature and 150 °C but decreases the creep properties. Among the Sr-containing ZA84 alloys, the alloy added 0.10 wt.% Sr obtains the optimum tensile properties at room temperature and 150 °C.