Title :
Thorium-containing effective cathodes
Author :
Djubua, B.Ch. ; Polivnikova, O.V.
Author_Institution :
SRPC Istok, Fryazino, Russia
Abstract :
The authors have described the technological methods of fabrication of cathodes based on the following materials: W-Th, W-ThO 2, W-ThO2-C and Re-Th. Their thermionic and secondary-electron emission, as well as the evaporation speed of thorium, have been studied. The dependence of the radioactivity of the cathodes impregnated with thorium on their storage time has been investigated. It has been found that in the process of impregnation of a tungsten sponge at 2000°C practically all isotopes of thorium settle down on the cold walls of the vacuum oven and the isotope of Th232 which possesses low radioactivity penetrates into the sponge. The cathodes radioactivity increases substantially in 1.5-2 months of their storing after the impregnation
Keywords :
composite materials; magnetrons; mixtures; radioactivity; rhenium alloys; secondary electron emission; thermionic cathodes; thorium alloys; thorium compounds; tungsten alloys; 1.5 to 2 month; 2000 C; Re-Th; Th isotopes; Th-containing cathodes; Th232 isotope; ThO2; W sponge; W-Th; W-ThO2; W-ThO2-C; cathode fabrication; evaporation speed; impregnation process; radioactivity; secondary-electron emission; thermionic emission; Cathodes; Electron emission; Fabrication; Insulators; Powders; Pressing; Radio control; Steel; Temperature control; Tungsten;
Conference_Titel :
Microwave and Millimeter Wave Technology, 2000, 2nd International Conference on. ICMMT 2000
Conference_Location :
Beijing
Print_ISBN :
0-7803-5743-4
DOI :
10.1109/ICMMT.2000.895627
