The oxidation-treated interface on tribological properties of carbon fibers-reinforced PTFE composite under oil-lubricated condition

The effect of air oxidation and ozone surface treatment of carbon fibers (CF) on tribological properties of CIF reinforced polytetrafluoroethylene (PTFE) composites under oil-lubricated condition was investigated. Experimental results revealed that ozone treated CF reinforced PTFE (CF-PTFE) composite had the lowest friction coefficient and wear under various applied loads and sliding speeds compared with untreated and air-oxidated composites. X-ray photoelectron spectroscopy (XPS) study of carbon fiber surface showed that, after ozone treatment, oxygen concentration was obviously increased, and the amount of oxygen-containing groups on CIF surfaces was largely increased. The increase in the amount of oxygen-containing groups enhanced interfacial adhesion between CF and PTFE matrix. With strong interfacial adhesion of the composite, stress could be effectively transmitted to carbon fibers; carbon fibers were strongly bonded with PTFE matrix and large scale rubbing-off of PTFE was prevented, therefore, the tribological properties of the composite were improved. Copyright (C) 2009 John Wiley & Sons, Ltd.