Experimental investigation of different cutting conditions in turning of Inconel 718

Abstract

Metal cutting or machining is a backbone of manufacturing industries. During metal cutting process heat generated has to be removed with cutting fluid. Commonly used cutting fluid is hydrocarbon oil based but it contributes to environmental imbalance and the ill health of the operator. Solid lubrication is a good alternative to conventional cutting fluid. Turning process is carried out on Inconel 718 in the present work with solid lubricants filled in parallel, perpendicular and cross direction textured cutting inserts. The two solid lubricants used are Molybdenum Disulfide (MoS 2 ) and Tungsten Disulphide (WS 2 ).Taguchi L9 orthogonal array is used to perform experiments and Analysis of Variance (ANOVA) method is used to identify the effect of each process parameter on the output. Solid lubricants are inherently solid as lubricant material but will become smooth due to frictional heat at point of contact. The result uncovered that a persistent film of solid lubricant is formed on the facet of the tool because of the heat produced due to thermal expansion. This film layer may knock down the friction in the machining zone. Among all, perpendicular direction textured cutting inserts have reduced friction and good surface finish is obtained. Compared with MoS 2 , WS 2 has shown better results in terms of surface finish.