Electrophoretic deposition of hydroxyapatite nano coating on etched titanium surface

Abstract

Hydroxyapatite (Ca,O(PO4)(6)(OH)(2), HAp) is biocompatible and bioactive, however, it is relatively brittle. The development of HAp coatings on medical metal surface is a good way to improve the mechanical properties of HAp. In the present study, a HAp coating with nano-structure on a roughened titanium surface was developed by electrophoretic deposition process. To decrease sintering temperature HAp nanoparticles synthesized by a wet chemical method was used. It was observed that the coating was uniform and showed no cracks. After sintering the HAp coating still remained nano structured. The surface treatment of Ti was applied to form a distribution of small pits and a TiO2 thin layer on the Ti surface that improves the adhesion of coating to the Ti substrate. It was shown that the bonding strength of coating was 18 +/- 2.5 MPa. The hardness and Young's modulus were 40.6 and 0.42 GPa, respectively.