Evaluation of corrosion resistance and cytocompatibility of graded metal carbon film on Ti and NiTi prepared by hybrid cathodic arc/glow discharge plasma-assisted chemical vapor deposition

Hybrid cathodic arc/glow discharge plasma-assisted chemical vapor deposition is used to prepare graded films on Ti and NiTi. XPS reveals the formation of a Ti and carbon graded interface between the substrate and carbon surface layer. The graded film significantly improves the corrosion resistance of Ti and NiTi in 154 mM NaCl as demonstrated by the smaller corrosion current density, larger resistance, and smaller capacitance. The graded film on NiTi shows near-capacitive impedance spectra and 14 times larger phase angle maxima at 105 Hz. In addition, the osteoblasts cells spread well on the graded film surface suggesting good cytocompatibility.