Surface oxidation study of molten Mg–Al alloys by oxide/metal/oxide sandwich method

The dynamic oxidation of molten Mg–Al alloy was investigated via the oxide /metal/oxide (OMO) sandwich method. The characteristics of sandwiches were explored using optical microscopy, scanning electron microscopy, X-ray energy dispersive spectroscopy, and X-ray diffraction analyses. The results showed the formation of porous oxide films with varying thicknesses from 0.43 to 16.7 mm. Both the measurements and calculations confirmed the literature findings that the oxidation product consists mainly of MgO and MgAl2O4 compounds. The increase in thickness and amount of folds formed on the oxide films implies the significant effect of aluminum in reducing the oxidation resistance of magnesium.