Accession Number : ADD006410

Title :   Method of Making a Ruggedized High Current Density Cathode.

Descriptive Note : Patent Application,


Personal Author(s) : Smith,Bernard

Report Date : 25 Jun 1979

Pagination or Media Count : 5

Abstract : A high current density cathode capable of operating at current densities of 2A/sq cm to 30A/sq cm in the temperature range of 900 degrees C to 1125 degrees C is prepared by machining a porous high purity tungsten pellet containing copper in its pores and also containing about 0.6 to 2 weight percent of an activator to the desired cathode shape without reducing the pores of the emitter pellet. The pellet is then fired at 1800 degrees C in a non-oxidizing atmosphere to remove the copper filler material. The pellet is then impregnated with the Ba5Sr(WO6)2 at a temperature of 1900 degrees C in a dry inert gas atmosphere and the impregnated emitter then fired in dry hydrogen atmosphere at about 1840 degrees C for about 2.5 to 5 minutes. (Author)

Descriptors :   *Patent applications, *Oxide cathodes, *Emitters, *Fabrication, Tungsten, Pellets, Barium compounds, Strontium compounds, Tungstates, Porous materials, Impregnation, Microwave tubes

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE