The Elastohydrodynamic Traction of Synthetic Base Oil Blends

The aim of this study was to investigate the elastohydrodynamic (EHD) properties of lubricant blends. Three base fluids of very similar viscosities, a polyalphaolefin, a diester and an alky lated aromatic, have been obtained and their EHD film thickness and traction behavior measured at a range of pressures. Blends of these fluids have been prepared and the influence of blending on film thickness and traction has been investigated. Traction measurements were conducted at film thicknesses between 100–200 nm and thermal analysis was incorporated to correct for in-contact shear heating. The blends showed a broadly linear relationship between the inlet pressure-viscosity coefficient and blend composition. Isothermal traction comparisons revealed that traction is not an additive property of lubricant blends.