Ti-O/Ti-N biomedical gradient films synthesized by metal vacuum arc plasma deposition and thermal oxidation

Summary form only given, as follows. In the last two decades, low temperature isotropic pyrolytic carbon (LTIC) has been the best material for fabricating artificial heart valves. However, the blood compatibility of LTIC is not sufficient for prolonged clinical use. TiO/TiN films were synthesized on 1Cr18Ni9Ti substrates. Ti-N films were deposited on 1Cr18Ni9Ti substrate by metal vacuum arc deposition. Then the as-deposited Ti-N films were oxidized at 600/spl deg/ for 25 min to synthesize Ti-O/Ti-N gradient film. In the complex Ti-O/Ti-N structure, the presence of Ti-O improves the blood compatibility and the main effect of Ti-N is to improve the mechanical properties. The composition, microstructure and mechanical properties of Ti-N and Ti-O/Ti-N gradient film were examined by XPS, XRD, microhardness tester and ball-on-disk wear test. Using a constant-potential method, the anodic polarization of the films has been measured, and the corrosion resistance properties of the films have been evaluated.