Tribofilm growth at sliding interfaces of PEEK composites and steel at low velocities

Abstract Tribological behaviors of carbon fibers (CF) reinforced poly-ether-ether-ketone (PEEK) composites are investigated at low speeds ranging from 0.01 to 0.2 m/s under pressures varying from 1 to 30 MPa. Nano-Bi2O3, nano-SiO2 and conventional solid lubricants (graphite and polytetrafluoroethylene) are further added into CF-reinforced PEEK, respectively. It is demonstrated that a small load and relatively high speed are favorable for the wear-reduction role of nano-Bi2O3, while the positive role of nano-SiO2 is pronounced at a high load and speed. Friction and wear-reduction roles of the solid lubricants are the most significant at low load and low speed. It turns out that functionalities of the fillers are closely associated with their roles in tribofilm growth governed by complex physical and chemical actions.