On the effects of bio-based nanolubricants formulation for the turning of Inconel 718

This study evaluates the effects of new bio-based nanolubricants blend formulation on the machinability improvement during the turning Inconel 718 alloys. Different proportion of coconut oil (CO), sodium dodecylbenzenesulphonate (SDBS), cocoamidopropyl betaine (CAPB) with 0.5% of aluminium oxide (Al₂O₃) nanoparticles were blended according to the mixture-design methodology to form the nanolubricants emulsion. Machining responses of tool wear, surface roughness, cutting power and spindle power were comprehensively assessed. The analyses revealed that a combination of 107.14 g of CO, 22.5 g of SDBS, and 15.36 g of CAPB was an ideal formulation for attaining excellent tribological and machining efficiency in the turning of the aforementioned alloy. Suitability of the formulated bio-based nanolubricants was also confirmed in terms of toxicity, corrosion resistance, and biodegradability. (author)