Multi-spherical probe machining by EDM: Combining WEDG technology with one-pulse electro-discharge

This paper describes a new hybrid technique combining wire electro-discharge grinding (WEDG) technology with one-pulse electro-discharge (OPED), to fabricate multi-micro-spherical probes. The results show that a burnished micro-spherical probe with diameter of about 40 μm could be formed instantaneously, which is not available with conventional machining methods. The unevenness of the radius is about 3 μm with repeatedly machining at the same conditions and the center shifting tolerances of the sphere is about 1 μm. Compared with micro-discharge electro-machining (EDM), the surface roughness of the probe is much smaller than discharge crater.