Fatigue and frictional behavior of diamond-like carbon films deposited by filtered cathodic vacuum arc technique

Diamond-like carbon (DLC) films were deposited by filtered cathodic vacuum arc (FCVA) technique. The structure and topography of the films were studied by Raman spectroscopy and atomic force microscopy, respectively. The hardness and elastic modulus of the films were measured by Nano-indenter. Nano-impact tests were carried out to investigate the anti-fatigue properties of the films. The tribological property was investigated by micro tribotester. The results indicate that the DLC coatings are smooth and dense with high hardness. The structure and characters of the films were influenced by the duty ratio of pulse bias voltage applied on the Si substrate during the deposition. As the bias duty ratio increased, the sp content of the film increased, as a result, the hardness of the film increased. The film deposited with the bias ratio of 70% presented the best anti-fatigue properties. The film deposited with the bias ratio of 50% had the lowest friction coefficient.