Study and evaluation of process parameter on Nimonic 75 alloy by Electrochemical micromachining

Abstract

Electrochemical micromachining (EMM) is an effective technique for creating micro features in difficult to cut materials like super alloys. Nimonic 75 a super alloy is used to fabricate the aero combustor parts as it can withstand hot gases during the gas turbine operations. In EMM process, Nimonic 75 alloy of thickness 500 µm has been machined by applying two combination of electrolytes. A solid tungsten carbide with a diameter of 500 µm has been used as the tool in the present examination. The variable process parameters considered are machining voltage, micro tool feed rate and duty ratio and their influence on performance characteristics namely circularity entry, exit and surface roughness were studied. By using multi-response technique TOPSIS, the best combination of process parameter is found. SEM was employed to observe the morphology of the machined surfaces.