INVESTIGATION OF VARIOUS ACTIVATOR REFRACTORY SUBSTRATE COMBINATIONS.
Abstract
An investigation was conducted to examine the properties of various materials suitable for dispenser cathode systems. Work function, evaporation rate, and poisoning effects have been measured in an effort to characterize these systems. It has been shown that various barium dispenser cathode systems may have effective work functions at 1250 K in the range of 2.40 to 1.80 ev and that excess barium oxide in the matrix gives emission characteristics similar to the oxide cathode. Low mass gases such as oxygen, carbon monoxide and carbon dioxide have deleterious effects on the barium dispenser systems while the effects of hydrogen and methane seem to depend strongly on the nature of the emitting surfaces as well as other parameters encountered in the normal testing procedure. A diode test in a commercial type of tube demonstrated the feasibility of a simplified fabrication procedure for producing a low work function emitter, phi = 1.80 ev at 1250 K. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1965
- Accession Number
- AD0617779
Entities
People
- John H. Affleck
- William T. Boyd
Organizations
- General Electric