Primary Study on Instantaneous Fabricating Mechanism of Tungsten Microelectrode Based on Single Discharge and Its Application

Based on conventional electrical discharge machining (EDM), a new method is presented for fabricating a tungsten microelectrode instantaneously in a single discharge. The influence of the main machining parameters, such as electrode material, polarity, working fluid, discharge duration, is analyzed by experiments to obtain microelectrode fabrication law. The fabrication mechanism is studied primarily through a lot of experiments, and the energy spectrum and grain structure analysis were carried out on the fabricated microelectrode. As the result of this research, a tungsten microelectrode with 350 μm in length and 30 μm in diameter can be fabricated on the top of the tungsten wire with 0.125 mm in diameter by this method. And it can be used as tool electrode in drilling 4 micro-holes continuously. At the tip of tungsten microelectrode, the radius is about 100 nm. It can be used as microprobe of scanner and detecting device. This method can increase the machining efficiency of microelectrode or microprobe greatly. It will be one of powerful methods of fabricating microelectrode or microprobe.