Effects of Electrical Parameters on the Microstructure of Microarc Oxidation Ceramic Coatings on Ti6Al4V Alloy

Ceramic oxide coatings were formed on T16A14V alloy surface by Microarc Oxida-tion(MAO) in Na2SiO3-KOH- (NaPO3)6 solution using an AC power supply. The effects of voltage and frequency of the power on growth kinetics, microstructure and phase constitute of the coatings were studied. The results show: with voltage increasing or frequency decreasing, the growth rate of the coatings increases, but the surface morphology becomes coarser. The as-deposited coatings are relatively dense and uniform, mainly composed of anatase and rutile TiO2- The phase constitute in the coatings depends on electrical parameters of voltage and frequency. With voltage increasing or frequency decreasing, the content of anatase TiO2 decreases, while rutile TiO2 increases and becomes the predominant phase.