Oxidation Behavior and Improvement in Nonflammability of LPSO-type Mg–Zn–Y–Sr Alloy

Mg97Zn1Y2 alloys with high ignition temperatures were developed by adding Sr. The addition of Sr resulted in the formation of a uniform and thin Y2O3 film. Mg–Zn–Y alloys containing at least 0.25 at.% Sr exhibited ignition temperatures of 1270–1320 K. As a result of EDS measurement, Sr was found to be concentrated in the Y2O3 film. In addition, a mixed film of MgO and SrO formed on the outer layer in the 1.5 at.% Sr-containing Mg97Zn1Y2 alloy. These findings suggest that the uniform and thin Y2O3 film that maintains high soundness at high temperatures was formed owing to valence control and the formation of a protective outer oxide film.