Fabrication of microelectrodes for EDM machining by a combined etching process

In this note, multi-headed microelectrodes were machined by a combined sequence process of WEDG, ultrasonic-aided chemical etching and an electrochemical anodic etching procedure. Electrodes were cut to 0.1 mm by a wire EDM machine from an original diameter of 3 mm in the first step. Electrodes were continually machined by chemical etching and anodic electrochemical etching. During electrolysis, copper impurity produced on the anode is not easily removed from its matrix. A ultrasonic mechanism was utilized to agitate the ferric chloride solution to clean the surface impurity off the electrode. The performance of ultrasonic-aided chemical etching was also studied. Micro single electrodes and foil electrodes were processed by chemical etching. Multi-headed microelectrodes can be machined to 30 µm by the combined sequence etching technology proposed.