Fabrication of micro tools using electrochemical machining with a reciprocating block electrode

Micro parts are increasingly being used in many applications. The machining of micro parts is inevitably dependent on micro tools, which play a key role in limiting the feature size and controlling the dimensional accuracy. However, the fabrication of micro tools is currently inefficient. This paper presents a novel electrochemical machining (ECM) method in which a reciprocating block (RBECM) is used as the tool electrode. In RBECM, the cylindrical workpiece reciprocates up and down in a straight line along its axis, while the block electrode simultaneously makes a feed movement. A mathematical model of the cutting edge length and width was derived to predict the size of the cutting edge tools. The results indicate that the model could achieve a good prediction accuracy. In addition, the effects of machining time on cutting edge width were experimentally investigated. Three types of stainless steel cutting edge tools with cutting edge widths of approximately 1/4, 1/2, and 3/4 of the diameter were successfully fabricated using a 5-mm-thick stainless steel block. The experimental results indicate that the machining time could be significantly reduced by 97.83%–99.5% compared to the ECM method using a tensioned metal wire as the cathode.