Thermionic cathode of high emissive power for an electric tube, and process for its manufacture
US4752713A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 5, 1987 |
| Grant date | Jun 21, 1988 |
| Priority date | — |
| Expiry date | Mar 5, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J1/14
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A reactionless thermionic cathode for electronic tubes consists of a metallic or ceramic support and an alloy, preferably an intermetallic compound, containing the actual emission-promoting element, with a metal from the group comprising those of the VIIIth vertical row of the periodic table and rhenium. The preferred activation substances are platinides of the elements having a low electron work function, predominantly Ba and La. The cathode is manufactured by wet-mechanical, cataphoretic or electroplating application of the activation substance to the support or by infiltration of the porous support having a pore volume of at least 10%. High emission current densities are obtained at relatively low operating temperatures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.