Abstract: Micro wire electrochemical machining is studied as a new method of micro fabrication in this article. It uses a tungsten wire as the tool electrode. Because there is no tool wear in wire electrochemical machining, it can easily be applied to the fabrication of micro structures by moving the tool electrode along a programmed path. The model of micro wire electrochemical machining is investigated. Flow of the machining gap is improved by adding vibrancy to wire electrode. Factors that affect the precision of micro wire electrochemical machining, such as voltage, pulse ontime, pulse period,and machining speed, are studied and compared and improvements are achieved by the optimization of these factors. Micrometer scale wire electrodes are fabricated by electrochemical etching machining. With tungsten wires of 10 μm and 2 μm in diameter, a micro structure less than 20 μm wide and a micro helix less than 8 μm wide are fabricated, and many complex micro structures with slit width of 20 μm are also machined.

Key words: micro wire electrode, vibrancy, electrochemical etching, electrochemical machining, microstructure