ZnO nanoparticles coated with oleic acid as additives for a polyalphaolefin lubricant

In this work, ZnO nanoparticles (NPs) were successfully synthesized and coated with oleic acid (OA). The mean diameter of these NPs (ZnO-OA) was around 11.5 nm, their core characterized by XRD coating FTIR Raman. Homogeneous dispersions at different concentrations (0.10, 0.25, 0.50, 0.75 1.00 wt%) ZnO-OA in polyalphaolefin 40 (PAO40) oil thermophysically tribologically characterized. Both density viscosity values increased the concentration NPs, reaching relative increments 0.5% 4.0%, respectively, for 1 wt% nanodispersion. Tribological tests performed 353.15 K using an Anton Paar MCR 302 rheometer equipped a tribological ball-on three-pins configuration testing module. Regarding behavior, optimal 0.25 (25% reduction friction coefficient 82% wear terms cross sectional area, respect to those obtained neat base oil). rolling mechanism owing spherical shape nanoadditives, transforming sliding into friction, mending effect could explain better performance nanolubricants that PAO40. addition, presence PAO40, iron oxides evidenced from confocal Raman microscopy on worn surfaces test PAO40 + dispersion.