Effect of Graphene Oxide on Wear and Corrosion Characteristics of Micro Arc Oxidation Coating on Titanium Alloy

In order to improve the wear and corrosion resistance of micro arc oxidation (MAO) coating on Ti-5Al-1V-1Sn-1Zr-0.8Mo alloy, 0-1.00 g/L graphene oxide (GO) was added to the electrolyte to prepare micro arc oxidation coating. The thickness, roughness, micro morphology and composition of MAO coating were characterized, and the wear and corrosion resistance of the coating were tested and analyzed. The results show that with the increase of GO content, the thickness of coating increases from 102.3 mu m to 115.3 mu m. The roughness reduces from 56.7 mu m to 32.9 mu m. The diameter of micropore on the surface of the coating is about 10-60 mu m without GO in electrolyte, and it decreases with the addition of GO. With 0.75 and 1.00 g/L GO, the diameter of micropore is stable at 10-20 mu m. XRD results show that the content of rutile TiO2 in the coating increases slightly with GO in eletrolyte, and the mass loss of the coating during wearing is significantly lower than that without GO. With 0.75 g/L GO, the binding force between coatings and substrate alloy is the largest, reaching to 53.3 N, which is 6.2 N higher than that without GO. After salt spray corrosion for 480 h, the coatings with GO content of 0.75 and 1.00 g/L have better corrosion resistance.