In order to reduce the degradation rate of fly ash cenospheres (FACs)/magnesium alloy (MA) degradable composite, the protective micro-arc oxidation (MAO) coatings were prepared on the composite. The corrosion resistance of the coatings was evaluated by immersion tests and potentiodynamic polarization tests in 3 wt% KCl solution. The results indicated that FACs and Mg₂Si did not participate in the coating-forming reaction. During the initial period of MAO, the growth rate of the coating on α-phase was faster than that on β-phase. FACs and Mg₂Si had a hindering effect on the growth of the coating and were gradually covered by the coating. With the extension of oxidation time, the thickness of the coating increased, and the growth mechanism changed from outward growth to simultaneous inward and outward growth. The microstructure of the coating changed from through-pores to complex porous structure with prolonged oxidation time. Both the immersion tests and the potentiodynamic polarization curves showed that the coating significantly improved the corrosion resistance of the composite, and the coating obtained with longer oxidation time showed better corrosion resistance.

为了降低粉煤灰空心球（FACs）/镁合金（MA）可降解复合材料的降解速率，在复合材料上制备了保护性微弧氧化（MAO）涂层。通过在3 wt％的KCl溶液中的浸没试验和电位动力学极化试验评估了涂层的耐腐蚀性。结果表明，FAC和Mg ₂ Si不参与涂层形成反应。在MAO的初始阶段，α相上的涂层生长速度快于β相上的生长速度。脂肪酸和镁₂Si对涂层的生长具有阻碍作用，并逐渐被涂层覆盖。随着氧化时间的延长，涂层的厚度增加，并且生长机理从向外生长改变为同时向内和向外生长。涂层的微观结构从通孔变为复杂的多孔结构，氧化时间延长。浸没测试和电位动力学极化曲线均表明，该涂层显着提高了复合材料的耐腐蚀性，并且在更长的氧化时间下获得的涂层表现出更好的耐腐蚀性。