采用正交试验法优化Al-Si合金硅酸盐体系微弧氧化电解液中钨酸钠、柠檬酸三钠、甘油浓度及电源脉冲频率、占空比、电流密度等工艺参数,研究工艺参数对膜层性能的影响。结果表明:微弧氧化最佳工艺参数为钨酸钠2 g/L、柠檬酸三钠2 g/L、甘油4 g/L、频率800 Hz、占空比30%、电流密度16.6~20 A/dm2;氧化膜主要由莫来石(mullite,3Al2O3·2Si O2)、α-Al2O3、γ-Al2O3相组成;莫来石含量较高,其中的硅元素主要来自铝合金基体。 Orthogonal experimental method was used to optimize the technological parameters of sodium tungstate, trisodium citrate, glycerin concentration and power pulse frequency, duty ratio and current density in the micro-arc oxidation of Al-Si alloy silicate system. Effect of film properties. The results showed that the best technological parameters of microarc oxidation were sodium tungstate 2 g / L, sodium citrate 2 g / L, glycerol 4 g / L, frequency 800 Hz, duty cycle 30%, current density 16.6-20 A / dm2; the oxide film mainly consists of mullite (3Al2O3 · 2Si O2), α-Al2O3 and γ-Al2O3 phases; the content of mullite is high, and the silicon element mainly comes from the aluminum alloy matrix.