Study regarding enhancement of antiwear properties of a grease, by using carbon nanomaterials based additives

Abstract

This study focuses on the improvent of antiwear properties of two categories of greases, sodium grease and lithium grease. Additives such as nanomaterials are essential to improve the properties of greases. Graphene, MWNT and fullerene are used in different quantitites (0.5 wt.%, 1.5 wt.% and 3 wt.%) to improve the antiwear properties. Nonadded samples were analyzed from density (ASTM D 1298), drop point (ASTM D 566), cooper strip test (ASTM D 130) and water resistance (DIN 51807) perspective. Also, nonadded and added greases were analized tribologicaly with HFRR test, and the results showed that all types of carbon nanomaterials investigated improve the tribological properties of the greases, but in the case of grease based on Li soap it can be observed an important decrease of friction coefficient for 3 wt.% graphene and MWNT. The most important decrease in the friction coefficient was recorded by Li35 with graphene additive. In case of grease based on Na soap, it was not notices important changes.