p. 970-975
TiN films were deposited on pure titanium specimens by reactive RF magnetron sputtering and gas nitriding methods. Pin-on-disk type wear tests were carried out to evaluate the effect of interfacial strength on the wear resistance of TiN films. The results showed that the wear property was improved remarkably by both methods, but the effect quickly disappeared after a large number of rotation cycles. Optical observation of wear scars during wear tests showed that delamination of a small part of the film occurred and the area extended within a small increase in rotation cycles. The delamination process of film during the wear test was discussed from a viewpoint of fracture mechanics, and the equation to evaluate the interfacial fracture toughness was derived. The interfacial fracture toughness of the sputtered and gas nitrided specimens decreased with increasing pin load and film thickness by fatigue damage along the interface accumulated during rotation cycles.
