Study of Particle Size Effect on the Performance of TiO2 Nanoparticles as Lubricant Additives on Vegetable Oil-Based Nanolubricants

Recently there has been an increase in concern regarding the use of petroleum-based lubricants. This has created an interest in readily available biodegradable lubricants such as vegetable oils. This work evaluates the rheological and tribological performance of grapeseed, and sunflower oils altered with 5, 18, and 40 nanometer titanium dioxide (TiO2) nanoparticles at differing concentrations. Block-on-ring tests were performed using the ASTM G-077-05 standard procedure. The effect of nanoparticle size and concentration and shear rate on the viscosity were evaluated and the experimental data was compared to conventional models. Roughness tests were performed on the wear scar of the blocks used. From the experimental results, it was found that the use of nanoparticles in vegetable lubricants were able to reduce the coefficient of friction, volumetric wear, and torque of the system. The development of these vegetable oil nanolubricants show great potential as possible replacements to mineral and some synthetic oils