Fundamental and practical evaluations of PEO coatings of titanium

Abstract

AbstractPlasma electrolytic oxidation (PEO) enables fabrication of high performance ceramic surfaces on the light metals, with thickness, topography, composition and structure controllable by the process parameters. The growth of anodic coatings on titanium has been investigated at a fundamental level, and understanding of coating growth has been enhanced. Discrete thickening at sites of dielectric breakdown, local growth at the metal/oxide interface and destruction of earlier formed oxide were shown, offering a new perspective on coating processes, including those aspects affecting coating efficiency. Routes to tailored coating compositions for enhanced biocompatibility have been developed, and carried through to in vitro evaluation. Fabrication of amorphous oxide, which is beneficial to biocompatibility, was achieved through anodising at controlled current densities and with use of complexing agents. Corrosion tests of the coatings revealed low titanium release into physiological solution, which is impo...