Characterization of diamond-like carbon films deposited on commercially pure Ti and Ti–6Al–4V

The diamond-like carbon (DLC) films deposited on the articulating surface of medical-grade Ti and Ti–6Al–4V were characterized. The DLC films were synthesized by r.f. plasma assisted chemical vapor deposition (PACVD) using C6H6 at 10 mTorr. For wear tests, the ball-on-disk type wear tester was employed by wearing a 5-mm diameter ruby ball against a rotating metal disk. The DLC coating dramatically improved the wear performance of Ti and Ti–6Al–4V, and protected the substrates from corrosion. The wear behavior of DLC films on the Ti-alloy was that of normal abrasive wear. However, the softer Ti substrate deformed plastically and the films were prefractured. The lifetime of the DLC coating in saline solution was reduced due to the delamination of the coating.