TRIBOLOGICAL PROPERTIES AND ELECTRICAL CONDUCTIVITY OF COMPOSITE LITHIUM GREASE REINFORCED BY IONIC LIQUID MODIFIED GRAPHITE

Abstract

Abstract: Using pentaerythritol ester as base oil, lithium complex soap as thickener, and adding ionic liquid modified graphite with different chain lengths as additives, lithium complex grease was prepared. The corrosivity and volume resistivity of the grease were tested. The tribological properties under current-carrying and non-current-carrying conditions were determined by using high-speed reciprocating friction and wear tester. The worn surfaces were analyzed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results show that the modified graphite material improves the wear resistance and conductivity of the base grease. Ionic liquids with longer chains form denser chemical films and exhibit the best friction reduction and anti-wear properties. Ionic liquids with shorter chains have lower volume resistivity and the best conductivity due to reduced electron entanglement.

Key words: modified graphite, ionic liquid, anti-friction and anti-wear, electrical conductivity

References

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