Tribological characteristics of Calophyllum ester based bio-lubricant – commercial engine oil blends

The main purpose of this research is to investigate the Tribological characteristics of Calophyllum Ester based Bio lubricant – commercial engine oil blends. The Bio lubricants used in this study are esters derived from Calophyllum seeds. The fatty acid content reveals the presence of saturates which form feed stock to esters. The physicochemical properties evaluated as per ASTM standards are found to be in an acceptable range. TMP (Trimethylolpropane) ester is blended with HP-RACER4 (Engine oil) in 5%, 10%, 15%, and 20% volume percentages respectively and tested for Anti-wear and Anti-Frictional properties using a four-ball tribo-tester. It was found that, although both the esters offer a very low coefficient of friction, the main drawback is their failure at higher loads. The blending of commercial lubricant with bio-lubricant resulted in lower friction and wear characteristics of the commercial lubricant. The optimum percentage of bio-lubricant in the commercial lubricant is found to be 20% which gave the desired results. (paper)