Reduction of stray corrosion by utilizing directional induction of hydrogen bubbles in bipolar pulsed ECM

Abstract

Electrolytes with bubbles can increase the impedance and reduce electrical conductivity for solution in electrochemical machining (ECM). In this paper, a method of electrochemical machining by using a bipolar pulse power supply and an auxiliary electrode to realize the reduction of stray corrosion is proposed. The auxiliary electrode is used to induce the generation of hydrogen bubbles on the surface of the workpiece and tool in the period of negative pulse, which can restrain the distribution of stray current in the period of positive pulse, thereby reducing stray corrosion and enhancing the machining precision of ECM significantly.