Functional Combined Biocoatings on VT-6 Alloy

Abstract

Electrochemical oxidation of spark-deposited coatings from intermetallic ТіАl₃ and TiN—3AlN nitride ceramics in 3% NaCl solution leads to a nanosized surface scale layer based on titanium oxides of varying composition: from higher to lower oxides toward the substrate. The highest corrosion resistance is shown by the intermetallic coating, which is confirmed by anodic oxidation polarization curves and layerwise Auger analysis of the protective films of titanium and aluminum oxides. A combined biocoating is produced as follows: ТіАl₃ spark-deposited coating based on VT-6 alloy—electrochemical oxidation in 3% NaCl solution—hydroxyapatite coating—subsequent laser fusion. Energy-dispersive X-ray spec-trometry has revealed a wide adhesion interaction area at the interface between the spark-deposited coating and hydroxyapatite, which agrees with smooth variation in microhardness. The coating shows strong adhesion to the substrate and biocompatibility with bone tissue.