Performance evaluation of cubic boron nitride tool in machining of titanium (grade-II) under minimum quantity lubrication

Abstract

The advantages of metal cutting fluids in machining are prominent, yet their utilization is accompanied by health and environment hazards. Besides, stringent environmental policies make the manufacturers to change over to dry turning, which is not viable during the machining of sticky material like titanium alloys. Therefore, the usage of minimum quantity lubrication (MQL) can be considered as a possible solution and a one step towards green manufacturing.The aim of this work is to investigate the machinability of titanium (grade-II) alloy with cubic boron nitride (CBN) tool under MQL conditions. The machining tests was performed under varying conditions of process parameters such as cutting speed (<i>V_c</i>), feed rate (<i>f</i>) and side cutting edge angle (approach angle <i>ϕ</i>). The experiments were planned and executed using response surface methodology (RSM). The tangential force (<i>F_c</i>), tool wear (<i>V_Bmax</i>) and power consumption (<i>K</i>) were selected as the response variables. The outcomes demonstrated that the <i>F_c</i> increases with the increase in feed rate and decreases with the increase in cutting speed and approach angle. Whereas the <i>V_Bmax</i> and <i>K </i> increases with the increase in feed rate as well as cutting speed. There is very less effect of approach angle on <i>V_Bmax</i> and <i>K</i>. Moreover, the results have been presented and optimized process parameters are obtained through multiple response optimizations using desirability function approach. In the end, the optimized parameters under MQL conditions are compared with the wet and dry turning. The MQL conditions have shown better results over wet and dry machining.