Optimization of Process Parameters in the Turning Operation of Inconel 625

Abstract

Many difficult to machine materials, such as Inconel 625Ni-based super alloy, are uncommon class of metallic materials with exceptional combination of greater thermal strength, toughness and resistance to deterioration. They have extensive applications in the manufacturing of new aero-engines, besides its enormous uses in marine, chemical and oil & petrochemical industries. In the context of its wide range of applications, there is a need for efficiently processing better methods in the manufacturing of such difficult to machine materials. This study consists of the turning operation of Ni-based super alloy Inconel 625 without coolant, carried out by physical vapour deposition (PVD) coated carbide inserts. The response parameters, such as surface roughness and material removal rate were evaluated in terms of cutting speed, feed rate and depth of cut. Sixteen experiments were carried out, based on Taguchi's Design of Experiments using orthogonal array. The resulting analysis was done based on response graph. The experimental results revealed that the feed rate was the most influential factor, followed by the depth of cut and cutting speed. The optimal parameters achieved were cutting speed of 90 m/min, the feed rate of 0.35 mm/rev and the depth of cut 0.2 mm.