Al-Si合金微弧氧化工艺优化研究

Technology improvement of micro-arc oxidation on Al-Si alloy

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。

The technological parameters of micro-arc oxidation of Al-Si alloy in silicate electrolyte were optimized by orthogonal experiment. The effects of technological parameters on the performance of ceramic film were studied. The results show that the optimized technological parameters are as follows:sodium tungstate 2 g/L,trisodium citrate 2 g/L,glycerol 4 g/L,frequency 800 Hz,duty cycle 30%,current density 16.6-20 A/dm2. The ceramic film is mainly composed of mullite,α-Al2O3,γ-Al2O3 phase,among which,the content of mullite is the highest,the silicon element in mullite is mainly from the subatrate of aluminum alloy.