Friction/Wear Behaviors of Magnetron Sputtered TiB2-C Composite Films on Ti6Al4V Alloy Substrate

The microstructure and friction/wear properties of TiB2-C (carbon-doped TiB2) films in TiB2-C/SiC double layer films (SiC films as interlayer) deposited on Ti6Al4V alloy substrate using magnetron sputtering technique at room temperature were investigated. The results show that the TiB2-C films exhibited the microstructural characteristics with nano-scale particles (domains), and the doped-carbon presented in manner of sp3 C-C and sp2 C-C bonds i.e. DLC (diamond-like carbon). The interface between the substrate and the SiC films and the interface between the SiC films and the TiB2-C composite films both showed good adhesion, with obvious element diffusions. As sliding against Si3N4 (silicon nitride) balls (2 mm in radius) using ball-on-disc type wear tester at room temperature under Kokubo simulation body fluid (SBF) and 50g load, the TiB2 -C composite films exhibited the friction coefficient of about 0.14 and the specific wear rate of 10.710-6 mm3 m−1 N−1. It is believed that the superior friction properties of the TiB2-C films are due to the role of the doped-carbon.