Effect of Graphene Addition During Micro-Arc Oxidation Process on Wear and Corrosion Properties of Composite Oxide Layers

—Ti and carbon steel are the materials most commonly employed in numerous industries. Nevertheless, adverse hardness, wear and corrosion resistance restrict numerous applications. We combined two surface processes technologies, thermal spraying and MAO, to produce a TiO 2 /Ti/Fe composite material. Firstly, a titanium (Ti) layer was prepared by thermal spraying on AISI 1020 carbon steel, and then additives in varying amounts were added to the electrolyte of micro-arc oxidation (MAO) to improve the wear and corrosion resistance. MAO current density and voltages were set at 35 A/dm 2 and 450 V, the operation time of MAO was 10 min. The concentration of graphene added to the electrolytes were 0, 0.01, 0.03, 0.05, 0.07, 0.09 g L –1 , and indicated as TiO 2 /Ti-F, TiO 2 /Ti-G1, TiO 2 /Ti-G3, TiO 2 /Ti-G5, TiO 2 /Ti-G7, TiO 2 /Ti-G9, respectively. Subsequently, surface roughness, thickness, microstructure, hardness, crystal structure, and composition were measured to confirm the properties of the oxide layer. Then the results of corrosion and wear tests to measure the wear and corrosion resistance of the oxide layer. As the results indicated, the specimen containing graphene (TiO 2 /Ti-G) has higher hardness, lower surface roughness, and about twice the thickness of oxide layer than the specimen without graphene (TiO 2 /Ti-F). In corrosion resistance, TiO 2 /Ti-G was at least about 30% more improved than TiO 2 /Ti-F, and TiO 2 /Ti-G7 was about 5 times better. In wear resistance, TiO 2 /Ti-G was at least 47% more improved than TiO 2 /Ti-F, and TiO 2 /Ti-G7 was about 80% better.