Title :
Time variations in the pressure exerted on the cathode during the operation of the cathode spot of a vacuum arc
Author :
Mesyats, G.A. ; Mourzakaev, A.M.
Author_Institution :
Inst. of Electrophys., Acad. of Sci., Ekaterinburg, Russia
Abstract :
The paper presents preliminary results of experiments on studying the time behaviour of the pressure exerted on the cathode of a vacuum arc by the cathode spot. The cathode was made as a copper film deposited on a glass substrate. During the operation of the cathode spot of a vacuum arc, sound waves propagate in the cathode, enter the glass and change its optical properties. This results in scattering of incident laser radiation. For a 3-A arc current of duration 50 ns an oscillogram of a current pulse of duration 200 ns, taken with a photorecorder, has been modulated with a period of about 25 ns, which suggests that the pressure is cyclic in character
Keywords :
cathodes; copper; glass; pressure; substrates; vacuum arcs; 200 ns; 25 ns; 3 A; 50 ns; Cu; arc current; cathode pressure behaviour; cathode spot; copper film; current pulse; cyclic pressure; glass substrate; incident laser radiation scattering; optical properties; oscillogram; photorecorder; sound wave propagation; vacuum arc; Acoustic propagation; Cathodes; Copper; Glass; Optical films; Optical propagation; Optical scattering; Pulse modulation; Substrates; Vacuum arcs;
Conference_Titel :
Discharges and Electrical Insulation in Vacuum, 1998. Proceedings ISDEIV. XVIIIth International Symposium on
Conference_Location :
Eindhoven
Print_ISBN :
0-7803-3953-3
DOI :
10.1109/DEIV.1998.740629
