Boundary lubrication properties and contact mechanism of carbon/MoS2 based nanolubricants under steel/steel contact

Lubrication mechanism of some carbon-based nanoparticles is unresolved and needs proper attention. In this work, friction and wear properties of carbon/MoS2 solid lubricants are tested in the boundary lubrication regime and further compared with oil-based binary and ternary nanolubricants. Results show that MWCNT and fullerene have high values of friction coefficient and wear rate in a dry medium. However, in lubricated medium with fomblin oil, they comply with the boundary lubrication mechanism and provide low friction and wear. The binary and ternary nanolubricants of oil-graphene, oil-MoS2, and oil-graphene-MoS2, oil-graphene-fullerene have provided enhanced wear and friction performance due to a build-up of a tribofilm between the contact zones. The interfacial contact mechanism depends on aggregation and particle rolling for dry and lubrication contact, respectively.