Comparation about efficiency of Al–10Sr and Mg–10Sr master alloys to grain refinement of AZ31 magnesium alloy

In the article, the effects of Al–10Sr and Mg–10Sr master alloys on the grain refinement of AZ31 magnesium alloy, are compared and analyzed. The results indicate that adding Al–10Sr or Mg–10Sr master alloys to AZ31 magnesium alloy could effectively reduce its grain size, but the refinement efficiency of Mg–10Sr master alloys is higher than that of the Al–10Sr master alloys. In addition, for a given melt holding time, the refinement efficiency of the two master alloys respectively increase with Sr adding amount increasing from 0 to 0.1 wt%, and the increasing laws are similar. For a given Sr adding amount, the refinement efficiency of Al–10Sr mater alloy gradually increases with the melt holding time increasing from 20 to 80 min, but its changing is not obvious for the Mg–10Sr mater alloy. The difference of refinement efficiency for the Al–10Sr and Mg–10Sr master alloys might be related to the dissolution modes and rates of Al4Sr and Mg17Sr2 phases in the melt of AZ31 magnesium alloy.