Enhanced tribological properties of PEEK‐based composite coatings reinforced by PTFE and graphite

Abstract The lubricating failure problems caused by friction and wear severely inhibit the regular operation and lifetime of artificial implanted joints. In order to improve their wear resistance effectively, the functional nano/micro‐composite coatings consisted of poly(ether‐ether‐ketone) (PEEK)/graphite/polytetrafluoroethylene (PTFE) were successfully prepared through electrophoretic deposition and heat treatment. Additionally, the friction and wear behaviors under different loads and lubricating mediums of the composite coatings were investigated systematically. The results show that the composite coating significantly increased the microhardness and wear resistance of PEEK coating. The introduction of graphite and PTFE fillers reduces the wear rates and coefficient of friction (COF) of the composite coating significantly. Especially under 10 N load conditions, the friction and wear tests show that the composite coatings drop by 80% of friction coefficient and an order of magnitude in wear rates compared to that of PEEK coating. The improved wear resistance can be attributed to the synergistic effect of PTFE and graphite fillers. As a result, the graphite provides good load‐bearing capacity and the PTFE lubricant endow a low friction coefficient for the composite coatings. Thus, this study provides a better approach to improve the wear resistance of PEEK‐based coatings.