Synergistic Effects of Nanoparticles and Ionic Liquids as Hybrid Lubricant Additives

Abstract

This Doctoral Thesis presents new designed nanolubricants as potential substitutes of conventional lubricants. Hexagonal boron nitride nanoparticles, graphene nanoplatelets, iron oxide nanoparticles (synthetized from iron mine sludge), three phosphonium ionic liquids and two polyalphaolefin base oils (PAO32 and PAO10) were the materials selected. The techniques used in the characterization of nanoparticles, base oil, ionic liquids, and the worn surfaces from the tribological tests were Raman, SEM, FTIR, HRTEM, XRD or 3D profilometry. Viscosity, density, viscosity index, stability and tribological behavior (friction and wear) of designed nanolubricants were studied. Most of them improved the overall properties of PAO32 40 % reduction in friction and 99 % in wear being stable up to 240 days.