Effect of Castor Oil and Biodiesel on Tribological Performance of Engine Oil

This study aims to investigate the effects of castor oil and biodiesel on the tribological performance of engine oil. Five mixed types of engine oils (B0, B5, B100, 5B-5% and 10B-5%) were used as the testing oils. Tribological performance of the test oil was evaluated under different temperature and duration by Cameron Plint TE77 reciprocating rig. SEM, EDS and AES/XPS were separately to characterize the morphology of worn surface and indentify the composition of the surface films. The results show that the anti-wear ability of the engine oil mixed with castor oil is better than that of the engine oil mixed with biodiesel oil. At room temperature, the anti-wear ability of engine oil is dominated by the physical adsorption capacity and hydrodynamic effects; while at high temperature, the anti-wear ability of engine oil is depend on the moment of decomposition of ZDDP additive and its chemical reaction rate.