Preparation and Evaluation of Zn Doped HAp Plasma Spray Biocombatible Coatings on Titanium

The development of Zn doped HAp plasma spray coating on titanium has been conducted. It was found that the ZnO peak density decreased greatly on X-ray diffraction results by increasing sintering time from 1 h to 5 h, meaning most part of Zinc ions were integrated into HAp crystal structure. With the sintered Zn doped HAp, plasma spray coating on titanium was prepared. The longterm credibility of Zn doped HAp plasma spray biocompatible coatings on titanium was evaluated by monitoring the changes in corrosion resistance with electrochemical impedance technique in physiological saline. The dissolution of Zn ion from Zn doped HAp was detected by ICP in physiological saline after a long-term immersion, implying the potential function of enhancing bone growth. The excellent adhesion of Zn doped HAp plasma spray coatings to titanium substrate was confirmed by three-point bending test.