Experimental investigation towards achieving optimised responses of Inconel 800 by high-speed dry turning

Inconel 800, widely used in defence, aviation, and oil refineries, is difficult to machine due to its toughness and work-hardening nature. This study examines the hard turning of Inconel 800, focusing on the impact of cutting speed, feed rate, depth of cut, and tool nose radius on key outcomes like surface roughness (SR), material removal rate (MRR), and cutting power (CP). Experiments were conducted using the Taguchi L9 orthogonal array, with analysis of variance (ANOVA) applied to determine the most significant factors. Grey relational analysis (GRA) was also used for multi-objective optimisation. Results indicated that feed rate had the largest influence, followed by tool nose radius, cutting speed, and depth of cut. The optimal machining parameters were a cutting speed of 182 m/min, a feed rate of 0.180 mm/rev, a depth of cut of 1 mm, and a tool nose radius of 1.2 mm.