Plasma Electrolytic Oxidation (PEO) Coatings

Abstract

The demand of modern technological society for light structural materials (Al, Ti, Mg) emphasizes a combination of good corrosion resistance with wear properties and functionalized surfaces. Their extensive field of applications ranges from mechanical aspects and transport components to bioengineering. Regardless of the final application, improved tailored surfaces are required to prolong service life and reduce long-term costs. Plasma Electrolytic Oxidation (PEO) is an exceptional candidate to achieve that goal: it enables a considerable improvement of the mechanical properties and corrosion resistance of light alloys, together with other characteristics such as improved biocompatibility. PEO is an environmentally friendly treatment process employed to produce relatively thick (10–100 μm) ceramic-like coatings on Mg, Al, Ti, and other valve metals, with incorporation of species from both the substrate and the electrolyte.