Evaluation of Optimum Cutting Parameters In Turning of NIMONIC 75 using RSM

Nickel based superalloys pose a real threat to industries when it comes to machining, due to their strength and hardness. Despite of this disadvantage, they are in high demand just because of their excellent performance at high temperature. NIMONIC 75 is one of such alloys which exhibits all the essential properties of a superalloy and has hardness less than INCONEL 718. This paper investigates the effect of AlTiN coated cemented carbide tool and various cutting parameters – speed, feed and depth of cut – on the surface integrity of NIMONIC 75 under dry machining condition using response surface methodology (RSM). Since no data related to machining of NIMNIC75 is available so far, so to find the initial values of each parameter preliminary experiments had to be conducted. These preliminary experiments showed that the value of surface roughness is less between the speeds from 100 m/min to 250 m/min and feed rate from 0.02 mm/rev. to 0.04 mm/rev. The final result shows the significance of each machining parameter individually on the surface integrity and a model to predict the value of surface roughness between that particular range of cutting parameters.