An investigation on the tribological properties of multilayer graphene and MoS₂ nanosheets as additives used in hydraulic applications

Recently, we have proposed an Electro-hydrostatic-actuator (EHA) based on a novel linear oscillating motor, which permits nanoparticle additives, such as layered graphene and MoS₂, using in hydraulic oil. Especially under a super smooth (Ra~5 nm) surface unlike past studies, the tribological properties of these additives is sent more highlight. In addition, oil temperature is introduced into the friction process. We show that the friction coefficient can be decreased to as low as 0.04 when adding MoS₂ nanaosheets for the chemical absorption and forming "available solid lubricant" under smooth surface and high temperature while multilayer graphene performs relatively unstable tribological properties because of agglomerates and crystal defects. It can be concluded that MoS₂ nanosheets possess better potential value for the application.