“…However, their low hardness, poor tribological properties, and high electrode potential give rise to the problems such as surface abrasion, contact corrosion, and marine biofouling, thus limiting the extensive applications in the complicated marine environment [5]. At present, some surface modification methods, such as anodizing [6,7], vapor deposition [8], magnetron sputtering [9], microarc oxidation (MAO) [10,11], etc., [12][13][14][15] are used to improve the corrosion resistance and wear resistance of the aluminum, magnesium, and titanium alloys. Moreover, as an in situ growth technique for preparing ceramic coatings, MAO has some attractive characteristics such as easy operation, high production efficiency, and environmental friendliness, thus being widely used in the surface modification of titanium alloys [16].…”