Influence of different featured tools on machining accuracy in electrochemical milling

Abstract

Drawbacks of electrochemical machining can be conquered to a large extent with the introduction of electrochemical milling technique. In this method, a simple shaped tool follows a predetermined tool path and material gets removed atom-by-atom from anode workpiece by electrochemical reactions through layer-by-layer approach. Keeping in mind the rising trend of electrochemical milling technique, this research work focuses to investigate the impact of major process parameters of electrochemical milling, for example, feed rate and milling layer depth on foremost responses like material removal rate and width overcut during electrochemical milling of Nimonic-263 alloy. In this research work, three different types of featured tools have been utilized and for each tool, ANSYS simulation has been carried out for analysing their impact on machining accuracy. Furthermore, these obtained simulated results have been confirmed by experimentation. Finally, an attempt has been made to produce more accurate ‘L’-shaped features on Nimonic-263 alloy with the aid of tool rotation and inner-spraying featured tools. This study confirms that mixed electrolyte, that is, NaCl(1M) + NaNO3(1M), tool rotation with internal flushing, number of outlets and the structure of the end face of the tool generate excellent machining accuracy with super finished surface with Ra value in the order of 0.07–0.08 µm during electrochemical milling of Nimonic-263 alloy.