Font Size: 

Nowadays, most of the manufacturing industry consumes petroleum-based oil as metalworking fluids (MWFs) during machining processes. However, petroleum-based oil is toxic, not renewable, biodegradable, and has a detrimental effect on both the environment and human health. Thus, the aim of this study is to evaluate the effect of mono and hybrid nanofluids on the tribological behavior and lubricating properties of modified calophyllum inophyllum (MCIO). The hybrid nanoparticles, which consist of activated carbon and hexagonal boron nitride (hBN), were combined with MCIO to create the nanofluids, which were then compared to synthetic ester. Kinematic viscosity and the viscosity index are used to determine the physical characteristics of nanofluids. The tribological performance of nanofluids was ascertained using four-ball testing. MCIOah (MCIO with 0.025 weight percent activated carbon and hBN) exhibited the highest viscosity index (317) among all samples. Its superior tribological performance was attributed to its lowest coefficient of friction (0.0459) and smallest mean wear scar diameter (581.3 μm). The worn surface of the steel ball of MCIOah demonstrated the best surface quality. Conclusively, it was demonstrated that environmentally friendly MCIOah hybrid nanofluid offers superior tribofilm and lubricant efficiency.