Machining performance of Inconel-718 alloy under the influence of nanoparticles based minimum quantity lubrication grinding

Abstract

Abstract Environmental and health problems associated with the conventional mineral-based cutting fluids has enhanced the quest of researchers to search for environment-friendly lubrication techniques. Minimum Quantity Lubrication (MQL) is the latest technique developing to reduce the use of coolants in machining. In the present work grinding of Inconel-718 (Ni-Cr alloy) has been examined under the influence of Al2O3 based Nanofluid Minimum Quantity Lubrication (NFMQL) technique using vegetable oils as the base oils in view of environmental conscious grinding. The grinding performance of Inconel-718 was evaluated in terms of surface roughness, grinding energy, cutting forces, temperature, and G-ratio. Nanofluids were prepared by adding 0.5 wt% and 1 wt% Al2O3 nanoparticles to the sunflower and rice-bran vegetable oils. From the results, it is observed that Al2O3 based nanofluid MQL with sunflower as base oil has given better results with respect to G-ratio, grinding energy, surface roughness, and coefficient of friction. Better value of surface roughness (0.5 μm) is achieved with 0.5 wt% concentration of nano-particles, whereas G-ratio (1.52), grinding energy(32.91 J/mm3) and tangential forces improved under nanofluid MQL condition with 1 wt% concentration of nanoparticles as compared to flood cooling. This might be due to the fact that while nanofluids flow through the wheel-workpiece interface, it results in the formation of a lubrication film that acts as ball bearing and reduces the sliding friction. Thus vegetable oils with the appropriate amount of Al2O3 nano-particles can give sufficient tribological properties with the environment and economic advantages.