Tri-layer impregnated cathode
US5418070A · kind A · utility
7Cited by
17References
19Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 28, 1988 |
| Grant date | May 23, 1995 |
| Priority date | — |
| Expiry date | Apr 28, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12167
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An impregnated cathode comprising three layers: a very thin emitting surface layer of metal such as an alloy of tungsten with a high fraction of an activating metal of the platinum group to provide low workfunction; an underlying, thin buffer layer of porous tungsten alloyed with a fraction of activating metal, to retard diffusion loss of activating metal from the emitting layer; and a substrate of porous tungsten impregnated with barium aluminate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.