Cathode erosion phenomena in a transferred-arc plasma reactor

Abstract

Phenomena occurring on the surface o/'a thoriated tungsten cathode operating in a trans.ferred-arc reactor were investigated. The efjeets of cathode geomet o, (pointedtip vs. fiat-tip)

Current density at the refractory cathode of a high-current high-pressure arc (two modes of cathode spot attachment)

“…2 Several experiments were performed with a pure tungsten cathode. If the plasma gas flow is purely axial (no swirl), the appearance is similar to that described in [18,19]: in the central region with a well-defined mosaic structure surrounded with a wide region covered with tiny craters. current 200 A).…”

An experimental study of the dependence on the current intensity of the erosion of thoriated tungsten cathodes in plasma arcs

“…The experimental corroboration of this prediction motivated the present paper. To the best of our knowledge, although thoriated tungsten cathodes have been the subject of intense experimental investigation in recent years [13]- [18], no experimental data supporting or rejecting the mentioned prediction has been reported.…”

“…In [13], an experimental study of the influence of the cathode geometry and of the plasma-forming gas composition on erosion of the thoriated tungsten cathodes was carried out, but at a constant current intensity of 200 A.…”

Electrode Phenomena in Plasma Sources

“…The importance of the ThO 2 dopant migration was also noted by Tsantrizos and Gauvin (1992). They studied the influence of the cathode shape on its erosion in Ar and He plasmas.…”