Electrodeposition of a hydroxyapatite coating on a biocompatible niti alloy

Abstract

The electrodeposition method was used to apply a hydroxyapatite coating (HAP) on the surface of a biocompatible NiTi alloy with the aim to enhance the corrosion resistance of the substrate and therefore decrease the release of nickel ions from the surface of the alloy. A uniform inner layer of HAP was formed and overlaid by clusters of spherical and flake-like morphological structures. The HAP coating exhibited super-hydrophilic wetting properties compared to the moderate hydrophilicity of the NiTi alloy. The barrier properties of the HAP coating were investigated by using potentiodynamic measurements. The HAP coating significantly enhanced the corrosion resistance of the NiTi alloy and confirmed the effective barrier properties of the coating, which can be used to minimise the nickel release in biomedical applications.