An Experimental Investigation of Micro-Machinability of Electric Discharge Machine for Stainless Steel - 316 Using Copper Electrodes

Abstract

Electric Discharge machines (EDM) could be essential in micromachining hard materials to produce fast, accurate, and deep holes. However, to successfully implement it in the industrial environment, the machining parameters for EDM machining micro-holes should be thoroughly investigated. This paper aims to study the feasibility of manufacturing micron-size holes using Electric Discharge Machining. The overcut, surface roughness, taper angle, MRR, TWR and microhardness were investigated by cutting micro-sized holes on 1mm thick stainless steel 316 using EDM with a copper electrode of 0.64mm diameter. The Response surface method and Artificial Neural Network is used to formulate the experiment layout, analyze each parameter's effect on the machining characteristics, and predict the optimal choice for each EDM parameters like Peak current, Pulse on time, Pulse off time. It has been found that these parameters have a significant influence on the machining characteristics such as overcut, surface roughness, taper angle, MRR, TWR and microhardness by varying one parameter at a time approach. Microscope and Micro-Hardness Tester, respectively observe the geometry of the machined microholes and heat-affected zone around the hole and slots.