Role of ZnO/MWCNTs hybrids nanoparticles addition on the tribological behaviour of SN150 paraffinic mineral oil

Abstract

Nanoparticle incorporation plays an active feature in heat transfer, ultimately enhancing the tribological process under boundary conditions of heat stress. Nanoparticles like zinc oxide (ZnO) and multiwall carbon nanotubes (MWCNT) are well known to significantly affect the cooling and lubrication applications, resulting in improved heat transfer and kinematic viscosity. The present work investigates the tribological performance of ZnO/MWCNTs hybrids as lubricant additive in the paraffinic type of mineral base oil of Group I (SN150) engine oil. The chemical composition of the modified and unmodified oil was examined by an inductively coupled plasma-optical emission spectrometer (ICP-OES), energy dispersive x-ray fluorescence (EDXRF) spectrometer, and Fourier-transform infrared spectroscopy (FTIR). A ring-on-disk tribotester was performed to investigate the tribological behaviour through the linear reciprocating mechanism alloy-steel contacts. The worn steel alloy surfaces morphology and chemical compositions were examined by scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDX), and 3D optical profilometer. Different ZnO/MWCNTs nanomaterial volumetric concentrations were examined in order to determine the most effective performance. According to the tribological results, ZnO/MWCNTs hybrid nanomaterials in the engine oil were found to have significantly higher friction temperature and antiwear capability than the base oil. A volumetric concentration of 3.00 wt% ZnO/MWCNTs nanomaterials to SN150 engine oil imparted excellent wear protection to the steel sample than the pure SN150 base oil. Based on the statistical analysis, the modified oil anti-wear performance was enhanced by reducing the wear loss by 80.5% and friction temperature by 55.8°C compared with the oil base.