Impregnated cathode
US4928034A · kind A · utility
1Cited by
5References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 18, 1988 |
| Grant date | May 22, 1990 |
| Priority date | — |
| Expiry date | Nov 18, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J1/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
According to the present invention, an impregnated cathode is provided wherein an alloy layer of iridium and tungsten is formed on a surface of a porous pellet impregnated with an oxide of an alkali earth metal, wherein a crystal structure of the alloy has an .epsilon.II phase comprising an hcp structure whose lattice constants a and c satisfy 2.76.ltoreq.a.ltoreq.2.78 and 4.44.ltoreq.c.ltoreq.4.46, respectively. The impregnated cathode of the present invention maintains stable electron emission characteristics from an early stage of operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.