Surface integrity and sustainability assessment in high-speed machining of Inconel 718 - An eco-friendly green approach

This paper primarily investigates productivity dependent surface integrity characteristics with keen focus on role of machining environments in machining of Inconel 718. Further a model has been proposed and developed for better understanding of sustainability in machining. For this high-speed turning of Inconel 718 at varying material removal rate (MRR) levels depicting productivity rates has been carried out under dry, flood coolant and water vapor machining environments, and then the resultant surface integrity is investigated in terms of surface roughness, surface damage and residual stresses. Later sustainability assessment has been also carried out using the developed model. The results show that good surface finish and residual stresses in compressive regime can be well ensured in high-speed machining range with low MRR under water vapor machining environment, while the same being feasible at high MRR under dry cutting. However the sustainability assessment gives highest product sustainability index of 82.92% at medium MRR under water vapor machining environment which emphasizes this to be a suggested favorable condition considering both, better surface integrity as well as sustainable cleaner machining alternative. Thus use of water vapor as coolant and lubricant in machining seems to be an eco-friendly machining technique and hence a better green manufacturing technology.