Experimental evaluation on the tribological properties of palm kernel oil by adding copper oxide nanoparticle

Abstract

The usage of vegetable oils is favoured upon mineral oils due to its biodegradability and non-toxicity. Since the usage of mineral oils caused environmental pollution, vegetable oils are seen as the alternative for promoting a better environment. Nowadays, vegetable oils are seen as the perfect lubricant since it exhibits good properties of a lubricant such as high viscosity index, low volatility, good lubricity, high flash point and low evaporative loss. Through research, it is found that vegetable oils develop lower coefficient of friction and high wear rate. However, the vegetable oils performance unfavourably when it deals with high pressure condition. Thus, nanoparticle is added as it serves as anti-wear additive. In this research, Palm Kernel Oil (PKO), Palm Olein (PO), Palm Kernel Oil + Copper Oxide Nanoparticle (PKO-CuO), Mineral Oil (SAE-40), Synthetic Oil (SAE15W-50, Syntium 1000) and Semi-Synthetic Oil (SAE15W-50, Syntium 800) are used as lubricant to be evaluated its tribological behaviours using fourball tribotester machine. The objectives of the research are to determine the coefficient of friction and wear characteristics at two different analysis, a) Standard Load Test conforming ASTM D4172 and b) Extreme Pressure Condition conforming ASTM D2783. The results are presented in many findings such as coefficient of friction (COF), wear scar diameter (WSD), surface roughness (Ra) and worn surface observation. For Standard Load Test, PKO-CuO shows better performance compared to Synthetic and Semi Synthetic Oil. However, under extreme pressure test vegetable oils shows bad performance. Among vegetable oils, PKO-CuO shows better performance as it fails at higher load. Hence PKO-CuO have promising lubricant trait and can be used as lubricant.