Miniaturization of WEDM using electrostatic induction feeding method

In this research, attempts were made to apply the electrostatic induction feeding method to WEDM because the method is able to eliminate the influence of stray capacitance in circuits thereby minimizing discharge energy to accomplish micro-WEDM. This method also allows non-contact feeding of electric current to the wire electrode, realizing highly accurate micro-WEDM because there is no wear of brush and the wire vibration does not depend on the cutting direction. In this research, micromachining properties of WEDM using the electrostatic induction feeding method were investigated using air and oil as the working dielectrics. A micro-slit of 32.4 μm in width and a micro-beam of 3.8 μm in width and 100 μm in length were obtained successfully. Moreover, non-contact feeding of electric current to the wire electrode was realized successfully, by sliding the wire electrode over a Teflon sheet of 30 μm in thickness laminated on a metal plate feeding electrode.