Synthesis and Tribological Properties of Oleic Acid-Modified Magnesium-Aluminum Nanoparticles as Lubricating in the SN500HVI Paraffinic Base Oil

The study focused on the performance enhancement of SN500HVI base oil by incorporation of the oleic acid modified MgAl 2 O 4 nanoparticles synthesized using combined of hydrothermal and sol-gel processes. The properties of the nanoparticles were studied by Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscope (FESEM), and X-ray diffraction spectroscopy (XRD) techniques. Nano particles with different contents were added into the oil, and a Pin-on-Disk apparatus was employed to investigate tribological behaviors of the oil. Subsequently, wear and friction tests were performed. The addition of nanoparticles to the oil improved its tribological properties, and decreased the friction coefficient by 15%, 59%, and 27%, using 0.25, 0.5, and 1 wt.% of nano particle content, respectively, in comparison with unloaded oil. The mean friction coefficients improved with increasing the nanoparticles in the base oil, and this value decreased to 0.071 at the optimal concentration of 0.5 wt.%. The results showed that the synthesized nanoparticles can act as an effective additive for improving the quality of lubricating oil due to their high flexibility, high malleability, and low hardness.