Corrosion behaviour of tetrahedral amorphous carbon (ta-C) filled titania nano tubes

TiO2 nanotubes were formed by anodic oxidation on Ti-6Al-7Nb and the nanotubes were filled with tetrahedral amorphous carbon (ta-C) by cathodic arc evaporation (CAE). The samples were characterized by field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and micro Raman studies. The corrosion behaviour of the Ti-6Al-7Nb substrate, substrate with self-organized TiO2 nanotubes (TNT) and ta-C filled TiO2 nano tubes (ta-C TNT) were investigated through electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization studies in simulated body fluid (Hanks' solution). The investigations show that the native oxide on the sample is replaced by a self assembled nano array by an anodisation process and the pores can be filled with ta-C. Potentiodynamic polarization and electrochemical impedance studies of ta-C filled TNT sample show that the corrosion resistance is comparable with TNT sample