BASIC RESEARCH IN THERMIONICS. PART I. CESIUM PERMEATION THROUGH TANTALUM. Summary Report No. 1, November 1, 1961 to October 31, 1962

Technical Report · Tue Jan 01 04:00:00 EST 1963

OSTI ID:4640491

Chapman, R A; Peterman, D A; Woerner, P F; Wakefield, G F

A plasma thermionic converter concept was proposed which uses cesium permeation through a tantalum emitter to obtain space-charge neutralization of electron current from this emitter. The concept was not feasible because the permeation rate of cesium through tantalum was too small. Cesium permeation through tantalum was studied at 400 to 1800 C with cesium pressures up to 13 mm Hg. This phenomenon was investigated for potential application as a hollow, ion- dispensing emitter for a plasma thermionic converter. Three methods were used in this study: measurement of ion current from a hollow, polycrystalline tantalum emitter internally connected to a cesium reservoir; measurement of weight-loss from a hollow, polycrystalline tantalum container with a cesium reservoir attached, with both suspended from a microbalance into a radiant furnace; and direct measurement of the diffusion coefficient in single-crystal and polycrystalline tantalum utilizing radioactive Cs/sup 134/. (auth)

• Research Organization: Texas Instruments, Inc., Dallas
• NSA Number: NSA-17-039705
• OSTI ID: 4640491
• Report Number(s): AD-296233
• Country of Publication: United States
• Language: English

Related Subjects

CESIUM
CESIUM 134
CRYSTALS
CURRENTS
DIFFUSION
ELECTRIC CHARGES
ELECTRONS
EMISSION
FURNACES
HIGH TEMPERATURE
ION SOURCES
IONS
MEASURED VALUES
NESDPS Office of Nuclear Energy Space and Defense Power Systems
NEUTRALIZATION
PHYSICS
PLASMA
PRESSURE
TANTALUM
THERMAL DIFFUSION
THERMIONICS