Investigating the effect of titanium dioxide nanoparticles in improving the properties of bio-based engine lubricating oils.

In this research, the effect of titanium dioxide nanoparticles was investigated, in improving the anti-wear, friction and physical properties of epoxied soybean oil. This research consists of four stages. In the first step, to prepare nano-lubricant mixtures, titanium dioxide nanoparticles with concentrations of 0.1, 0.2 and 0.5 wt% were combined with epoxidized soybean oil. In the second step, an ultrasonic bath was used to disperse the nanoparticles in the lubricant, and span80 surfactant was used to stabilize the fluid and prevent solid nanoparticles from settling. In the third stage, the experimental tests were performed, including the wear test using the pin-on-disk device and the physical properties of nano-lubricants, including pour point, flash point, and viscosity, by relevant devices and based on international standards. In the fourth stage, the results of the analysis and the performance of nano-lubricants mixtures were compared with the base fluid. Based on the results of the tests, it was determined that the best performance is related to the nano-lubricant mixture with a concentration of 0.5 wt% of titanium dioxide nanoparticles, which reduced the coefficient of friction and wear by 7.93% and 57.14%, respectively. Also, the viscosity decreased by 11.95% and the flash point decreased by 3% compared to the base oil, but with increasing concentration, no significant change was observed in the pour point of nano-lubricants.