Effect of Wire Electrical Discharge Machining Parameters on various Tool Steels using Grey Relational Analysis

Materials having very high strength are causing hardship to machine using traditional machining methods. Therefore, consequently, unconventional machining process such as ECM, USM and EDM is developed for machining such materials. Wire EDM is an unconventional metal removal technology utilised to produce parts of any profile. Wire EDM machining parameters were optimised using Grey Relational Analysis for machining of tool steels such as H13, D2 and Oil Hardened Non-Shrinking Steels (OHNS). Optimum parameters are identified by conducting L27 OA experiment on H13, D2 and OHNS considering factors like GV, Ton, Toff and the wire feed by Taguchi based GRA method considering MRR, SR and cutting width (kerf) as the performance characteristics. Nine experiments were conducted with each tool. Objective is to obtain maximum MRR, minimum SR and minimum kerf simultaneously. The significance of the machining parameters was determined using ANOVA. From the response table and response graphs, the optimum process parameters were chosen. This method helped to improve the WEDM process.