Abstract
Diamond-like carbon (DLC) films are widely known as protection films and solid lubrication films. DLC films are promising candidates for tribomaterials in a water hydraulic system. The friction properties were investigated by using a ball-on-disk type reciprocating tribometer. The low-friction mechanism of DLC films in water environment was proposed. TEM analyses indicated that the localization of chromium on the worn surface of matting balls. Additionally, a TOF-SIMS analysis indicated that the hydroxyl group on DLC surfaces was generated by the tribochemical reaction with surrounded water. An ultra-thin water layer should be located in the friction surface. Furthermore, the adhesion of DLC films was investigated. The evaluation of adhesion was not yet established. We proposed an evaluation method using the high-frequency liner-oscillation tester (SRV) with stepwisely increasing of normal load. The delamination of films would be classified on the basis of the process of wear.
