Analysis of ECM Phenomena with Equivalent Circuit for Electrolysis

We investigated the interaction between the tool-electroge and workpiece in electrochemical machining (ECM) by establishing an equivalent circuit model for electrolysis. A Zener diode was introduced for the first time to account for the fact that Faradaic current only starts to flow after the potential across the double layer at the solid and liquid interface exceeds the threshold of the electrolytic reaction. After determining the circuit parameters by comparing experimental and analytical results, we examined the ECM characteristics, the Faradaic current as well as the influence of the pulse-off time on the machining accuracy and removal rate. It was found that our model incorporating the Zener diode accurately describes the ECM process. From the simulation, the pulse-off time was found to have a significant impact on machining accuracy.