6533b823fe1ef96bd127f4e8
RESEARCH PRODUCT
Barium depletion study on impregnated cathodes and lifetime prediction
Alexis SteinbrunnFabian PoretA. MonterrinR. Le DozeJ.l. RicaudJ.m. Roquaissubject
Materials scienceAnalytical chemistryEvaporationGeneral Physics and Astronomychemistry.chemical_elementThermionic emissionBariumSurfaces and InterfacesGeneral ChemistryTungstenCondensed Matter PhysicsAccelerated agingCathodeSurfaces Coatings and Filmslaw.inventionchemistrylawPelletPorositydescription
In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK).
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2003-06-01 | Applied Surface Science |