Process parameter optimization in electrical discharge machining of ph 15 5 stainless steel material using multi criteria decision making mcdm method

Abstract

In the modern era, the development of new material needs various technology improvement methods due to inadequate manufacturing capability. Mainly, the machining technology is lacking in producing materials with complex shapes at the desired qualities. The above said complications can be overcome by using advanced machining technology like Non-Traditional Machining (NTM) processes. Electrical Discharge Machining (EDM) is one of the widely used techniques in Non-Traditional Machining (NTM) especially for finishing operation of high precision components, which are not possible by conventional material removal process. This is also one of the reasons for adopting the EDM in various applications of aerospace, nuclear, power plant, chemical, and medical industry. The materials like stainless steel alloys are used in similar applications which possess high strength and toughness. The selected material of Precipitation-Hardening (PH) 15 5 martensitic stainless steel faces issues in machining operation that undergoes by a conventional method. PH15-5 is one of the precipitation hardening stainless steel materials that contains high chromium and nickel content alloying elements. The corrosive resistance and high strength of this material property leads to many application such as actuator parts for modern fighter aircraft, high-pressure valves, turbine blade, fitting, gears, high strength shaft, and fasteners. Therefore, it requires the EDM type of machining process for obtaining the desired quality of components. Based on the literature review, the dimensional accuracy of the machined features is important, and the researchers are preferring more than 3 mm of machining depth to obtain more accurate data for the analysis purpose. Features of the machined surface depend on the property of the workpiece and electrode material. Many electrodes are readily available in the market, in which the copper is the cheapest one among the other electrodes.