Pyrolytic Graphite in the Design of a Compact Inert Heater of a Lanthanum Hexaboride Cathode
- 1 April 1970
- journal article
- research article
- Published by AIP Publishing in Review of Scientific Instruments
- Vol. 41 (4), 585-587
- https://doi.org/10.1063/1.1684584
Abstract
Pyrolytic graphite serves two functions in a new type of LaB6 cathode; it supports and heats the LaB6 emitter. The high anisotropic resistivity of pyrolytic graphite allows a compact heater‐emitter design a few millimeters in size, and the chemical compatibility of graphite with LaB6 at the operating temperature of about 1500°C prevents any lifetime reducing chemical reactions between the two materials. Typical heating power inputs have been measured to be 15 W at a heating current of about 3 A. One of these LaB6 cathodes has been tested in a demountable vacuum system at an average emission current density of 1.6 A/2cm for over 900 h without signs of impending failure.Keywords
This publication has 6 references indexed in Scilit:
- Poisoning of LaB6 CathodesJournal of Applied Physics, 1969
- Refinement of Lanthanum Hexaboride for Cataphoretic Deposition on RheniumReview of Scientific Instruments, 1967
- Electron Gun using Long-Life Lanthanum Hexaboride CathodeJournal of Applied Physics, 1967
- Thermionic emission properties of a lanthanum hexaboride/rhenium cathodeBritish Journal of Applied Physics, 1965
- Cataphoretic Coating Lanthanum Boride on Rhenium FilamentsReview of Scientific Instruments, 1965
- Boride CathodesJournal of Applied Physics, 1951