Improving the machining efficiency of electrochemical micromachining with oscillating workpiece

To enhance the machining efficiency of electrochemical micromachining (EMM), the low-frequency sinusoidal oscillating motion was applied to the workpiece, while the tool electrode moved in controlled trajectory. Mathematical model for the material removal rate (MRR) and the pressure in the interelectrode gap were derived. The mechanisms of enhancing the mass transport in the interelectrode gap induced by the oscillating workpiece during EMM have been analyzed, based on the variation of pressure in the interelectrode gap. An experimental setup has been developed for EMM. Experiments were conducted to investigate the influences of a vibrating amplitude and frequency on the machining efficiency, stability, and achievable maximum feeding rate of the tool electrode. The results indicated that a larger vibrating amplitude and a proper frequency were suitable for obtaining a higher material removal rate during EMM. The highest feeding rate of 0.3 μm/s has been obtained utilizing oscillating workpiece during the machining of microgrooves. Both the theoretical and the experimental results indicated that the oscillating workpiece during EMM was beneficial to improving the machining efficiency. Finally, microstructures with the circular profiles were processed using EMM, by a tool electrode feeding rate of 0.3 μm/s and the workpiece oscillation with the amplitude of 0.5 μm and frequency of 60 Hz.