Enhancement of the Homogeneity of Micro Slits Prepared by Wire Electrochemical Micromachining

Wire electrochemical micromachining (WEMM)is promising in the fabrication of metal micro parts or devices because it has many advantages in machining structures with high aspect ratios. The smaller machining gap in WEMM is particularly interesting because higher accuracy can be obtained. However, with such a narrow machining gap, removing electrolysis products and renewing electrolyte become difficult, which would lead to a poor homogeneity of the micro slit. In this paper, the combined method of anode vibration and cathode travelling is used to improve the homogeneity of the micro slits. The influence of the parameters of anode vibration and cathode travelling on the side gap and the homogeneity of micro slits is experimentally investigated. A frequency of 100 Hz with an amplitude of 5 μm and a frequency of 2 Hz with an amplitude of 70 μm are optimal for anode vibration and electrode travelling, respectively. Finally, both groups of micro slits and cantilever curved micro beams with good homogeneity are successfully machined under the optimal conditions.