Synthesis and characterization of high-voltage electrodeposited diamond-like carbon protective coating on TiAlV biomedical substrates

Diamond-like carbon films (DLC) were deposited on TiAlV alloy substrates in liquid methanol by the liquid-phase electrodeposition technique in nitrogen atmosphere at room temperature. The voltage applied between the electrodes was higher than 1800?V because of the use of resistive organic liquid. The electrochemical behavior of TiAlV and DLC-covered TiAlV samples was investigated in fetal bovine serum at 37?degrees C and atmospheric pressure without agitation, using electrochemical impedance spectroscopy and potentiodynamic polarization as electrochemical techniques. For surface characterization techniques, we used scanning electron microscopy, X-ray diffraction, and Vickers microhardness measurements. Raman spectroscopy analysis of the films revealed three broad bands at approximately 1227, 1356, and 1550?cm-1 related to possible diamond nanoparticles, to TiC or amorphous TiOx, and to D- and G-bands of DLC, respectively. The metallic ion release in bulk solution was studied by inductive coupling plasmamass spectrometry. In uncoated samples, the release of metallic ions in bulk solution was much higher than in DLC-coated samples. Also, the corrosion resistance and Vickers microhardness of DLC-coated samples were improved in comparison with the uncoated samples. Copyright (c) 2012 John Wiley & Sons, Ltd.