Abstract: Perfluoropolyether (PFPE) grease was prepared by using different types of polytetrafluoroethylene (PTFE) and anti-wear additives. Based on the detection techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption, the structure and microscopic morphology of PTFE thickener were characterized and analyzed.Two standardized test platforms, namely the four-ball friction testing machine and the SRV friction and wear testing machine, were used to explore the tribological behavior characteristics of PFPE grease.Meanwhile, the detection techniques of SEM, energy dispersive spectrometer (EDS), three-dimensional profilometer(micro-XAM-3D),andX-ray photoelectron spectrometer (XPS) were comprehensively employed to deeply analyze the composition and morphological characteristics of the friction pair surface and infer the lubrication mechanism of different greases.The results show that the P3-type PTFE micropowder with large pore structure has good thickening ability, and the prepared grease has the best wear reduction and wear resistance, which the minimum friction coefficient is only 0.101, the wear volume is only 7.29×10⁵ μm³. The grease with borate added exhibits more outstanding anti-friction and anti-wear properties, specifically manifested as a reduction of approximately 14% in the coefficient of friction and a decrease of approximately 50% in the volume of wear. Borate additives form a solid solution structure to construct a complex permeable protective film at the friction interface. This special protective film can effectively reduce the coefficient of friction and enhance the surface's anti-wear ability.

Key words: perfluoropolyether, grease, tribological properties, protective film