在硅酸盐-磷酸盐复合电解质中添加羟基磷灰石纳米粉体和氢氧化钠进行改性处理,然后采用该电解质对医用镁合金丝材进行微弧氧化处理。研究电解质中氢氧化钠含量对镁合金丝材表面陶瓷涂层微观组织结构和性能的影响。结果表明:对电解质改性后,镁合金丝材的微弧氧化起弧电压大降低且氧化速度更快。镁合金丝材在添加2 g/L氢氧化钠的电解质中进行微弧氧化处理后的耐腐蚀性能改善幅度显著。在模拟体液的早期浸泡过程中,微弧氧化处理过的镁合金丝材表现为缓慢且稳定的腐蚀降解。在浸泡28 d后,镁合金丝材表面的保护性陶瓷涂层尚未破坏,但浸泡60 d后,镁合金丝材出现了显著的腐蚀降解。 Hydroxyapatite nano-powder and sodium hydroxide were added into the silicate-phosphate composite electrolyte for modification, and then the electrolyte was used to micro-arc oxidation the medical magnesium alloy wire. The effect of sodium hydroxide in electrolyte on the microstructure and properties of ceramic coatings on magnesium alloy wire was studied. The results show that the starting voltage of microarc oxidation of magnesium alloy wire is greatly reduced and the oxidation rate is faster after the electrolyte is modified. Magnesium alloy wire added 2 g / L sodium hydroxide in the micro-arc oxidation of the corrosion resistance of the significant improvement. During the early soaking of simulated body fluids, the MAO-treated magnesium alloy wire showed slow and steady corrosion degradation. After soaking for 28 days, the protective ceramic coating on the surface of the magnesium alloy wire has not been damaged. However, the magnesium alloy wire shows significant corrosion degradation after soaking for 60 days.