Accession Number : ADD011036

Title :   Fast Turn-On Osmium Coated Cathode.

Descriptive Note : Patent Application,


Personal Author(s) : Marrian,C R K ; Haas,G A ; Shih,A

Report Date : 15 Mar 1984

Pagination or Media Count : 17

Abstract : This abstract discloses a fast turn-on refractory coated cathode comprising a porous tungsten metal matrix impregnated with barium calcium aluminate and coated with osmium. The osmium coating has a planned series of interruptions with each interruption being on the order of several microns in width to thereby expose the tungsten. These interruptions permit the barium and oxygen from the impregnant to rise to the cathode surface during activation or reactivation to form a desired near monolayer of barium and oxygen to enhance electron emission. Thus, this cathode design provides a fast turn-on characteristic even after shelf storage. (Author)

Descriptors :   *Patent applications, *Cathodes, Refractory coatings, Tungsten, Matrix materials, Porous materials, Impregnation, Barium compounds, Calcium compounds, Aluminates, Osmium, Interruption, Oxygen, Surfaces, Activation, Layers, Electron emission, Quick reaction, Starting

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE