Developing a Process Chain with WEDG Technology and Pulse ECM to Fabricate Ultra Micro Pins

Abstract

Micro tools are widely used in some industry application, such as medical device, touching probe and micro electrode for EDM. Micro tools with diameter less than 50μm have been successful to fabricate since the development of WEDG technology. Recently, some reports point out that it is also possible to produce micro tools with diameter less than 5μm by WEDG technology. However the machining efficiency and tool will be bending when the diameter is less than 10μm by WEDG Technology. Due to the electro-discharge and fluid action force, it is a still critical problem to fabricate a straight and tiny micro tool with diameter less than 10μm. In order to fabricate micro tool with diameter less than 10μm, a combined process of WEDG technology and electro chemical machining was proposed in this study. After WEDG technology applying to fabricate a micro tool with diameter approximately 40μm. Pulse ECM was used on the same machine to re-shape micro tools with diameter below 10μm. The experimental results show that with charge-coupled device (CCD) assistance the hybrid process is possible to fabricate a length of 1mm and diameter 10μm micro tool. To fabricate high quality micro tools, the parameters of WEDG technology and ECM such as discharge voltage, processing time, concentration of electrolyte will be also investigated in this study. It is expected that micro tools could be fabricated more efficiency by this process.