Experimental investigation of micro-holes in electrochemical machining using pulse current

Electrochemical micro-machining (EMM) has become one of the main machining methods for production of miniaturized parts and components. Utilizing a developed EMM set-up, sets of experiments have been carried out to investigate the influences of some of the predominant electrochemical process parameters such as pulse frequency, feed rate of tool, machining voltage and electrolyte concentration on the machining accuracy of micro-hloes. According to the present investigation, the most effective zone of pulse on time and electrolyte concentration can be considered as 15-50 mus and 30-50 g/l, respectively, which can gives a desirable machining accuracy for micro-holes. A machining voltage range of 6-10 V can be commended to obtain high machining accuracy. From the micrographs of the machined micro-holes, it may be observed that a lower value of electrolyte concentration with moderate machining voltage and moderate value of pulse on time will produce more accurate shape of micro-holes.