工艺条件对镁合金微弧氧化陶瓷层孔隙率的影响

Effect of Electrolyte Concentration and Striving Voltage on Pore Rate of Ceramic Film by Micro-arc Oxidation

利用微弧氧化技术在AZ91D镁合金表面原位生长陶瓷膜,通过调节电解液浓度、控制起弧电压,以探索减少陶瓷层中孔洞及孔径的工艺方法。结果表明:选择合适的电解液的浓度可以减少陶瓷层中孔隙,控制微弧氧化过程中的起弧电压也可以减少陶瓷层中的孔隙和孔径。

Micro-arc oxidation（MAO） method was employed to deposit oxide film on AZ91D alloy at constant current in electrolyte containing NaESiO3, NaF, glycerol and KOH. The experimental phenomenon that occurred at the anode and cathode was analyzed. Microstructure and aperture were analyzed by scanning electron microscopy （SEM）. The effects of some factors on the pore and aperture of the ceramic coating, such as electrolyte concentration and striving voltage were investigated. The results show that the behavior of MAO process and the quality of the MAO coatings have been changed by different electrolyte concentration and various striving voltage. Namely, with the increasing of electrolyte concentration, the coating thickness and pore increased, and the coating thickness and aperture increased with the increasing of striving voltage increasing.