Self-Lubricating PEO–PTFE Composite Coating on Titanium

Abstract

A self-lubricating plasma electrolytic oxidation⁻polytetrafluoroethylene (PEO⁻PTFE) composite coating was successfully fabricated on the surface of commercially pure titanium by a multiple-step method of plasma electrolytic oxidation, dipping and sintering treatment. The microstructure and tribological properties of the PEO⁻PTFE composite coating were investigated and compared with the PEO TiO2 coating and the PTFE coating on titanium. Results show that most of the micro-pores of the PEO TiO2 coating were filled by PTFE and the surface roughness of PEO⁻PTFE composite coating was lower than that of the PEO TiO2 coating. Furthermore, the PEO⁻PTFE composite coating shows excellent tribological properties with low friction coefficient and low wear rate. This study provides an insight for guiding the design of self-lubricating and wear-resistant PEO composite coatings.

Keywords

• self-lubricating
• composite coating
• titanium
• plasma electrolytic oxidation (PEO)
• polytetrafluoroethylene (PTFE)