Development of controlled micro-discharge at the atmospheric pressure

The generation method of sub-millimeter sized plasma was developed through controlling the electrical discharge in the range from glow to arc discharge with use of the experimental torch device and the newly designed high-voltage power source. The electrical discharge was established between a cathode of the electrolytic polished tungsten electrode and an anode of stainless steel sheet. Features of the thermal materials processing by micro-discharge were experimentally investigated. It is shown that the power density of micro-discharge reaches higher than 109 W/m2 and sub-millimeter sized melt spot can be obtained at the surface of anode metal.