New Promising Ceramic Coatings for Corrosion and Wear Protection of Steels: A Review

Steel is one of the most substantial alloys used in various applications due to its ravishing properties such as high toughness, good machining ability, and low cost. However, steel suffers weak corrosion and wear resistance to address the current industry demands. Indeed, employing a ceramic coating produced via plasma electrolytic oxidation (PEO) has been exploited to enhance steel's protective properties against corrosive and abrasive conditions. Nevertheless, steel surface features in striking contrast to valve-metals hamper the formation of ceramic coatings. For this purpose, we review novel methods that researchers implemented to resolve this issue and then describe mechanisms involved in forming and altering the composition, microstructure, and morphology of the PEO ceramic coatings. Subsequently, corrosion, wear, and tribo-corrosion performance of coatings are discussed in light of modification developed due to the formation of the most efficient PEO ceramic coatings.