Anticorrosion composite coatings on biodegradable Mg alloys: Electrochemical studies

Abstract

Calcium phosphate coatings consisting of magnesium oxide and hydroxyapatite, which accelerates osteogenesis (bone formation), were formed on magnesium alloys of the Mg–Mn–Ce and Mg–Zn–Zr systems by plasma electrolytic oxidation (PEO). The phase and elemental composition, morphology, and anticorrosion properties of the coatings were studied. Approaches to the formation of composite protective coatings on the basis of the PEO layer using superdispersed polytetrafluoroethylene were developed. Treatment of the PEO-coating with a polymer material reduces the adverse effect of different-level defects. After a single polymer deposition, corrosion protection effect of the composite layer substantially (by more than three orders of magnitude) increases with respect to the base PEO coating.