Investigating the effect of MoS2 nanoparticles in engine oil on reducing friction and wear of automotive parts

The growth of mechanical and related industries is significantly influenced by the lubrication industry. Recent research has focused heavily on lubricants, particularly concerning the utilization and overexploitation of finite resources, as well as compliance with environmental regulations. As a nano lubricant, Molybdenum disulfide greatly enhances the tribological properties of lubricating oils and represents a critical category of lubricating nanoparticles. This study employed various methods to prepare a suspension of engine oil containing 5% by weight of molybdenum disulfide sulfide (MoS2) nanoparticles, which was then assessed visually for stability. After determining the stability of the selected sample, its stability was further evaluated through dynamic light scattering analysis and elemental analysis. The initial dispersion of nanoparticles in ethanol was done using an ultrasound mixer, recognized as the most effective method. Subsequently, additional ultrasonication was carried out after adding the surfactant to the ethanol solvent solution. The coated nanoparticles were separated using high-speed centrifugation, and the oven was utilized for drying. Ultrasonication was performed for 15 minutes after adding 5% by weight of the coated nanoparticles to the oil. The effects of nano-sized particles in the base oil were examined through four-ball and pin-on-disk wear testing methodologies. SEM images showed that increased pressure on the friction surfaces during scratch pin wear caused the grooves to fill with nanoparticles and facilitate surface repairs, thus improving the surface finish and maintaining consistent groove formation.