A Cost Effective Approach to Explore the Electrical Discharge Machined Surface Characteristics of Nimonic C263 Superalloy

The EDMed surfaces are subjected to stringent applications in aerospace, automotive engines, are still possessing limitations viz. higher cost of production, poor surface integrity, quality and numerous other technical problems. The evidence regarding the solution of these problems is extremely scattered and are not adequate and in some specific points. In view of this, we propose an experimental study to explore the machined surface characteristics of Nimonic C263 superalloy machined with different electrodes including copper, tungsten, and copper-tungsten through technical analysis and proper elucidation. The EDMed surface characteristics are evaluated in terms of surface roughness (SR), surface crack density (SCD), recast layer thickness (RCT), microhardness (MH) and machining cost (C) which are functions of controllable parameters viz. current (I), voltage (V), pulse on time (T_on), duty factor (τ) and a class of tool material. To explore the major outcomes, a detailed parametric study of the surface characteristics is conducted. The machined surface is analyzed using a field emission scanning electron microscope (FESEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) techniques to evaluate the pre-machining and post machining scenarios. Finally, a novel complex proportional assessment (COPRAS) technique is performed to discover the most cost-effective and precise level of parameters. A confirmative test is performed to check the feasibility of the mathematical model obtained for utility degree (U_i) which depicts the 6.13% error in between predicted and experimental results. The proposed work will be valuable in delivering a competent plan for fabrication and cost-effective production of EDMed parts, thereby resolving current challenges and constraints and paving the way for future development.