Abstract
To accelerate the bone growth around a metallic implant and to achieve the mechanical characteristics needed for biomedical applications, a hydroxyapatite/pure titanium (HA/Ti) composite coating was produced on NiTi alloy substrate by laser cladding. The experimental results showed that an excellent metallurgical bonding between the coating and the substrate was obtained. Owing to decomposition of HA under irradiation of high power laser, the microstructures of coating were mainly composed of CaO, CaTiO3, titanium phosphide and HA phases. In vitro experimental result demonstrated that HA/Ti composite coating made the bioactivity of NiTi alloy improved remarkably while restraining Ni ion from releasing.
The work described in this paper has been supported by the Research Grants Council of Hong Kong (project no. PolyU5261/04E), and part contents of this paper were presented at Bioceramics 19. One of the authors (S. Yang) is grateful to Science Foundation of Nanjing University of Science and Technology (grant no. 2011PYXM07) and project supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (grant no. 20113219110034).