Title :
Optical investigation of arc spot formation on cold cathodes in air
Author :
Nachtigall, Klaus P. ; Mentel, Juergen
Author_Institution :
Klockner Moller Elektrizitats-GmbH, Bonn, Germany
fDate :
10/1/1991 12:00:00 AM
Abstract :
The column of a high current arc was magnetically blown against a cathode positioned perpendicularly to the arc axis. A linearly increasing voltage was applied to this electrode. It was shown by high-speed photography that the arc spot ignition is initiated by an intensified light emission on the cathode within an area of approximately 40-μm diam. SEM micrographs from the traces produced during the ignition phase revealed that craters with diameters of some micrometers are formed within a burning spot, which corresponds in size to the optical spot. They are similar in size and shape to the craters formed by vacuum arcs on cathodes of the same material
Keywords :
arcs (electric); photographic applications; plasma diagnostics; 40 micron; SEM micrographs; air; arc axis; arc spot formation; burning spot; cold cathodes; craters; high current arc; high-speed photography; ignition; light emission; linearly increasing voltage; magnetically blown column; optical investigation; vacuum arcs; Cathodes; Electrodes; High speed optical techniques; Ignition; Optical materials; Photography; Shape; Stimulated emission; Vacuum arcs; Voltage;
Journal_Title :
Plasma Science, IEEE Transactions on
