The adverse effects of mineral oil-based metal cutting fluid on environmental sustainability have led to increased industrial concerns. Alternatively, biodegradable lubricants such as vegetable oil has a more positive impact with equivalent performance, but insufficient research on their benefits demands further exploration. This work features extensive experimental investigations on machining of Inconel 718 using novel formulations of coconut bio-based oil with enhanced nanoparticles and coco-amido-propyl-betaine. Bio-based with 0.8 wt% of Al2O3 managed to minimise the rapid growth of tool wear and prolong the tool life by 40.17%. Conversely, bio-based with 0.5 wt% of Al2O3 yielded lower values of cutting force (64.32 N), spindle power (2070 kW), specific cutting energy (6.55 W/mm3), and surface roughness (0.29 μm). The outstanding performance of bio-based nanolubricants contributed to superior machinability efficiency and eco-friendly machining environments.
