Mechanics of Cooling Lubricating Fluid (CLF) through chip deformation in eco-friendly machining of Inconel 718

摘要

This paper investigated the cutting mechanics aspects of the minutely explored eco-friendly Cooling and Lubricating Fluid (CLF), water vapor, in high-speed turning of Inconel 718 using coated carbide tools. Water vapor acts as a coolant and lubricant; however, the lubrication aspects need to be understood separately from the cooling. For this, the effect of water vapor CLF's parameters like nozzle diameter, stand-off distance, pressure and flow rate, as well as main machining parameters like cutting speed, feed rate and depth of cut in providing the necessary lubrication and/or cooling action were assessed in terms of the chip deformation coefficient, basically a prime indicator of lubrication status. The nozzle diameter and stand-off distance along with feed rate and depth of cut were found to be the most significant factors. Within the investigated regime, the optimal combination of process parameters for a lower chip deformation coefficient and hence, better lubrication, were a cutting speed of 80 m/min, feed rate of 0.20 mm/rev, depth of cut of 0.25 mm, nozzle diameter of 2 mm, stand-off distance of 20 mm and a pressure of two bar. Thus, by proper selection of optimal parameters, usage of water vapor for providing effective cooling and lubrication in machining can be a promising effort toward green manufacturing for the near future.