Tribological properties of carbon nanotubes as lubricant additives
F. Abate, A. Senatore, V. D’Agostino, C. Leone, M. Sarno, P. Ciambelli
university of salerno, IT
Keywords: nanoubrificant, carbon nanotubes, tribological properties
Abstract:Tribological performances of innovative lubricant additives based on IF-WS2 and other transition metal dichalcogenides like MoS2 nanoparticles have been widely investigated in recent years. The boundary lubrication regime is the main target for the benefits of well-tested or potential additives, since the film thickness of the lubricating base is no longer sufficient to preserve separation of the opposing metal surfaces. Among the various investigated materials, nanocarbons such as fullerenes and nanotubes have proven attractive and promising tribological properties in terms of friction reduction and anti-wear action. In this work, experiments have been carried out on a pin-on-disc tribometer to get assessment about the effectiveness of such additives as friction reducers in boundary and mixed lubrication regimes. Multiwalled carbon nanotubes of different geometric characteristics (diameter, length, thickness) were prepared by catalytic CVD. Several tests, performed on arrays of operating conditions in terms of speeds and loads, have aimed to underline the friction loss saving of the lubricated pair by varying nanoadditive concentration in the oil formulation. AISI 316 steel pins with different surface finish have been used to consider the effect of roughness parameters, while the counterpart surface is an X155Cr13MoKu steel disc, 60 HRC.