In this study, MgO/Mg composites were prepared using direct melt oxidation to verify the effects of elastic deformation and microplastic deformation on the damping properties. It was found that the composites have high damping properties at a certain strain amplitude, which indicated that the damping properties of the magnesium matrix were effectively enhanced by the in situ-synthesized oxide particle. In addition, other damping mechanisms different from the G–L dislocation damping mechanism exist in MgO/Mg composites, i.e., the damping mechanism of the microplastic deformation, leading to a model of microplastic deformation damping established and its mechanistic analysis.
