To demonstrate the viewpoint that the mechanical properties and corrosion resistance requirements of magnesium alloys are well coordinated, a series of magnesium alloys with low rare earth content were designed and prepared using alloying technology. The alloy composition was optimized using tissue analysis and performance testing methods. By performing solid solution treatment and hot extrusion treatment on the selected alloy, the alloy had excellent mechanical properties and corrosion resistance at the same time. Then, the surface modification process was used to reduce the decay rate of the corrosion medium on the mechanical properties of the alloy and extend its service life. The results indicated that preparing Micro-Arc Oxidation (MAO) coatings on solid solution extruded alloys could reduce the corrosion rate of the alloy and prevent the mechanical properties of the alloy from rapidly decaying in corrosive media. The surface of MAO coating was porous, mainly composed of the MgO phase, and the structure was composed of an outer loose and inner dense layer. As the oxidation time increased from 3 min to 20 minutes, the surface pore size increased, and the porosity decreased gradually when the average thickness of the coating increased from 10 μm to 42 μm.
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