Regular Article

Optimization of machining parameters in turning of Inconel 718 Nickel-base super alloy

¹ Laboratory MAI, National Engineering School of Tunis, University of Tunis El Manar, 1002 Tunis, Tunisia
² IPEI Nabeul, Mrazka University Campus, 8000 Nabeul, Tunisia
³ Laboratoire de Mécanique Appliquée des Nouveaux Matériaux (LMANM) Université 8 Mai 1945 Guelma, Guelma, Algeria
⁴ Mechanics and Structures Research Laboratory (LMS), May 8th 1945 University, 24000 Guelma, Algeria

^* e-mail: wassilaenit@gmail.com

Received: 14 June 2019
Accepted: 24 December 2019

Abstract

The high hardness and low thermal diffusivity along with the tremendous strength at high temperatures has rendered the nickel-base super alloys Inconel 718 one of the most difficult to cut material. It possesses a wide range of applications including aerospace as well as chemical and petrochemical industries, and is primarily used in the manufacture of aircraft gas turbines, space vehicles, nuclear power systems, and medical equipment. The present study is mainly focused on the cutting parameters optimization that leads to minimum surface roughness, cutting force and power, specific energy and maximum productivity during the turning of the molded Inconel 718 using a carbide cutting tool. The analysis of variance (ANOVA) method is applied to identify the cutting parameters that most influence the response criteria, and the response surface methodology (RSM) along with the desirability function (DF) approaches are further used to develop the prediction model that addresses the optimization procedure. The different parameters are considered one at a time in order to evaluate the sensitivity of the response (OFAT). This procedure led to identify the nose radius (r_ε), the feed rate (f), the depth of cut (a_p) and the cutting speed (V_c) as the most significant factors on both the surface roughness and the cutting forces. Furthermore, the product (f × a_p) and the cutting speed (V_c) were found to be the most dominant factors on the specific energy.