マイクロプラズマアークの発生とそのパワー密度に関する研究

抄録

In order to realize practical application of micro-plasma arc welding, the generation method of sub-millimeter sized plasma arc was developed through controlling the DC 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 tungsten electrode and an anode of stainless steel sheet through plasma constriction nozzle made from heat-resistant material of Boron Nitride. It is shown that the micro-plasma arc with use of sub-millimeter diameter nozzle is stabilized as the plasma beam of which size corresponds to the nozzle diameter. And decrease of nozzle diameter increases the power density of micro-plasma arc at the anode surface. Sub-millimeter sized melt spot can be obtained with the current of 1 A and discharge time of 5 ms.