Tungsten-iridium impregnated cathode
US4675570A · kind A · utility
13Cited by
5References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 11, 1986 |
| Grant date | Jun 23, 1987 |
| Priority date | — |
| Expiry date | Apr 11, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Porous agglomerates are made from pure tungsten by sintering fine particles together and mechanically breaking down the mass to form some agglomerates considerably larger than the particles. These agglomerates are mixed with fine iridium powder and sintered to form a porous mass. The mass is machined to the cathode shapes and impregnated with an alkaline earth aluminate. The large agglomerates alloy with the iridium only on their outer surface. Their pure tungsten interior provides the surfaces to reduce the alkaline earth oxide to the metal which activates the cathode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.