Study on influences of bubbles on ECM gap phenomena using transparent electrode

To understand the influences of bubbles generated in the machining gap on stability and accuracy of electrochemical machining, gap phenomena were observed directly using a transparent electrode made of SiC single crystal, which is electrically conductive and optically transparent. The criterion of boiling for electrolyte was obtained from both experiment and heat transfer analysis, and the relationship between the occurrence of electric discharge and the volume fraction of bubbles in the gap was clarified. The influences of the rotation of the tool electrode and the radial flow of electrolyte in the gap on the machining accuracy were also investigated. (C) 2016 CIRP.