Parametric Evaluation in Context to the Functional Role of Eco-Friendly Water Vapour Cutting Fluid Through Chip Deformation Analysis in HSM Of Inconel 718

Demand for increased production rates, better quality, and incorporation of green manufacturing practices has been continually challenging the manufacturers. This could be feasible by adopting high-speed machining (HSM) using eco-friendly cutting fluids but with careful process control. On these lines, the current paper explores process characteristics of the exotic superalloy Inconel 718 being turned at high speeds with tooling as coated carbide inserts and eco-friendly cutting fluid as water vapour. The experiments were carried out by varying three process parameters, viz. cutting speed, feedrate as well as water vapour pressure, following central composite design based on response surface methodology. A special tool holder with an in-built fluid supply channel was used to facilitate precise delivery of water vapour cutting fluid onto the machining zone. The process mechanics has been analyzed with the aid of the chip deformation coefficient as the same is a crucial indicator revealing the cutting fluid performance in machining as a result impacting the surface integrity, tool wear, machinability, etc. Analysis revealed that the response surface quadratic model for the chip deformation coefficient was statistically significant. The feedrate, vapour pressure, and the interaction between feedrate and vapour pressure were highly dominating factors influencing the chip deformation coefficient, with contributions of around 23.41%, 25.33% and 21.49%, respectively. An increase in vapour pressure was highly beneficial in lowering the chip deformation coefficient on account of water vapour’s better penetrability and performance into the machining zone. Overall usage of cutting fluid as water vapour within feasible HSM parametric ranges can be notably beneficial.

Keywords: Chip deformation coefficient, Eco-friendly, High-speed machining, Inconel 718, Water vapour.