Tribological properties of diamond-like carbon films deposited by vacuum arc

Abstract

Conventional artificial hip joints with metal-on-metal pairings are subject to wear resulting in a large number of metal wear particles, limiting the lifetime of implants. In order to improve the wear protection of artificial hip joints, diamond-like carbon (DLC) films with high quality have been synthesized by a vacuum arc adjustable from anodic to cathodic operation mode at a DC bias to the substrate. The influence of the bias on the wear behavior examined with disc-on-disc and cavitation erosion testing was investigated. DLC film with a high density (3.03 g cm−3) and low wear rate (1.04 × 10−5 g h−1) could be deposited by vacuum arc at a DC bias (−750 V). Furthermore, no delamination was observed after the DLC-on-DLC tribopairs were tested under a high conducted load (300 N) and velocity (0.1 m s−1) for 55 h, which indicated DLC film at the bias of −750 V has good tribological properties.