High Current Density and Long-Life Nanocomposite Scandate Dispenser Cathode Fabrication

Autor:	Jinfeng Zhao, Diana Gamzina, Neville C. Luhmann, Na Li, Ji Li, Z A Munir, Larry R. Barnett, M. Banducci
Rok vydání:	2011
Předmět:	Materials science Nanocomposite Fabrication chemistry.chemical_element Nanotechnology Thermionic emission Tungsten Cathode Electronic Optical and Magnetic Materials law.invention chemistry law Particle Electrical and Electronic Engineering Composite material Porosity Current density
Zdroj:	IEEE Transactions on Electron Devices. 58:1221-1228
ISSN:	1557-9646 0018-9383
DOI:	10.1109/ted.2011.2109723
Popis:	A nano-Sc2O3-added W powder for use in high current density thermionic cathodes has been made using a solution-gel method with the following controllable uniform average particle sizes: ~72, 146, 272, and 587 nm. Using these powders, nanostructured Sc2O3 -added tungsten matrices with uniform nanosized tungsten grains and homogenous pore distribution were obtained. Nanocomposite Sc2O3-added W impregnated cathodes have been prepared from these powders and have shown excellent emission properties. For example, space-charge-limited current densities of 40 ± 1 A · cm-2 at 850°C and 170 ± 5 A · cm-2 at 1050°C have been obtained using a 300-nm Sc2O3-added (4.77 wt.%) W powder. Life testing is ongoing with 50 ± 2.5 A · cm-2 current density emission demonstrated at 1050°C after 10 680 h.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::85edd869955fd6b65390c05051ae2fcb https://doi.org/10.1109/ted.2011.2109723 Zobrazit plný text záznamu