Performance optimisation of electrochemical micromachining of micro-holes on Inconel 625 alloy

摘要

This work involves producing micro holes on Inconel 625 alloy through Electrochemical micromachining (EMM) process. The input parameters investigated are supply voltage, electrolyte concentration and duty ratio. The cathode tool used is a conical tipped stainless steel needle and the electrolyte is acidified sodium nitrate solution. Taguchi design of L9 Orthogonal Array is followed for experimental work. The performance analysis is done through process responses such as machining rate and overcut. The experimental results have given the optimum parameter combination for higher machining rate as 16 V supply voltage, 35 g/lit electrolyte concentration and 45% duty ratio and for lesser overcut as 12V, 35 g/lit and 45% duty ratio. The influence of input parameters on the process is also studied. The multi-objective optimisation technique used has produced 12 V, 30 g/lit and 45% duty ratio as the ideal combination for achieving higher machining rate and lower overcut.