Feed rate of wire electrochemical machining using pulsed current

The effect of various parameters on the feed rate in electrochemical machining has been investigated. Parameters considered were velocity of the electrolyte flow, nozzle diameter, material, diameter and tension of the wire, pulse period and peak value of the applied voltage. On the assumption that the feed rate is limited by accumulation of generated sludge or gas, the feed rate equation and favourable pulse conditions were derived and verified experimentally. The rate was improved by applying a shorter pulse period than the 'residential' time of the electrolyte between electrodes. Above the critical pressure, at which the feed rate is a maximum, the adverse effects of wire vibration cannot be neglected. Measures proposed to prevent it were reduction of nozzle diameter and length of wire span, and increase in applied voltage and wire tension.