Tribocorrosion behavior of DLC-coated CoCrMo alloy in simulated biological environment

Due to renewed interest in hard-on-hard prosthetic joint replacements, especially metal-on-metal (MOM) and ceramic-on-metal joints (COM), concerns about debris and released metal ions from wear and mechanical-enhanced electrochemical (tribocorrosion) processes have raised. In order to reduce the metal debris quantity and the release of metal ions, a diamond like carbon (DLC) film is deposited on CoCrMo alloy by using a filtered cathodic vacuum arc technique (FCVA). The tribocorrosion behavior of DLC coated CoCrMo alloy is studied in bovine calf serum and 0.9% NaCl solution by using a linear reciprocating pin-on-plate tribometer with an integrated electrochemical cell. The open circuit potential (OCP) and the polarization test are monitored during the reciprocating pin-on-plate test. The results show that the absorbed protein layer on DLC surface play a positive role in reducing wear and metal ion release. The presence of DLC layer improves the tribocorrosion resistance of CoCrMo alloy. And The DLC film has a potential application on hard-on-hard prosthetic joint replacements and it can effectively reduce the metal debris quantity and the release of metal ions. (C) 2012 Elsevier Ltd. All rights reserved.