Research On The Effects Of Molybdenum Diselenide On Tribological Propertites Of PTFE

As the rapid development of modern science and technology, polymer-based composites are gradually replacing some of the metal-based materials due to their excellent enhancing properties, which is one of the major tendencies of materials development. The applications of polymer and polymer-based composites in fields of aerospace, machinery and chemistry industries are becoming wider due to their excellent properties such as light weight, high strength and corrosion resistance. Thus, it is of great theoretical significance and application value to study new polymer-based composites. Molybdenum diselenide(Mo Se2) belongs to one of the transition metal of chalcogens, which possesses stable structure and good self-lubrication property. However, there are few studies on its application in self-lubrication area.In this paper, Mo Se2 was added into polytetrafluoroethylene(PTFE) to fabricate PTFE/Mo Se2 composites and the mechanical and tribological properties of the composites were investigated. The effects of content of Mo Se2 and surface modification of Mo Se2 on the mechanical and tribological properties of the PTFE/Mo Se2 composites were systematically studied. Based on this, tribological properties of PTFE/Mo Se2 composites with 20% surface modified Mo Se2 under different working conditions(contact pressure and sliding velocity) were studied. Confocal scanning laser microscopy(CSLM), scanning electron microscope(SEM) and energy dispersive spectrometer(EDS) were used to analyse the worn surface characteristics and wear mechanisms of the PTFE/Mo Se2 composites with 20% surface modified Mo Se2.Research results showed: for mechanical properties, the hardness of PTFE was increased and tensile strength was decreased by incorporating Mo Se2. Mechanical properties of PTFE filled with surface modified Mo Se2 was significantly superior to the one without modification. For tribological properties, content of Mo Se2 and its surface modification barely affected the anti-friction property of PTFE but anti-wear property of PTFE was greatly increased. And properties of PTFE/Mo Se2 composites with 20% surfacemodifided Mo Se2 were outstanding. Tribological properties of PTFE/Mo Se2 composites with 20% surface modified Mo Se2 differed under different contact pressures or sliding velocities and the suitable working condition for this kind of composite was mild or low pressure/velocity.