Electron stimulated thorium adatom enrichment on the surface of thoriated tungsten below 2300K

Autor:	Agoston Boroczki, L. Balázs, M. Menyhárd, I. Gaál, L. Petrás, E. Horváth, A.L. Tóth, S. Gurbán
Rok vydání:	2006
Předmět:	Auger electron spectroscopy Reflection high-energy electron diffraction Materials science Auger effect chemistry.chemical_element Thorium Halide Electron Tungsten symbols.namesake chemistry Electron beam processing symbols Atomic physics
Zdroj:	International Journal of Refractory Metals and Hard Materials. 24:343-349
ISSN:	0263-4368
DOI:	10.1016/j.ijrmhm.2005.10.006
Popis:	The evolution of the surface composition of thoriated tungsten has been followed up by means of Auger electron spectroscopy (AES) upon various heat treatments performed below 2300 K. It turned out that the surface composition dramatically depends on the current density of the electron beam exciting the Auger electrons, and no Th adatom enrichment has been observed without electron beam irradiation in this temperature range. It has been shown that the sources of Th adatoms are the thoria particles attached to the free surface of the wire. It is proposed that electron irradiation induced oxygen depletion of the W–ThO2 system is the main reason for thorium release onto the free surface from the thoria particles. The relation of the topic to the electrode performance in metal halide lamps is also discussed.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4ae0febb059a7a41d65da009a18d6630 https://doi.org/10.1016/j.ijrmhm.2005.10.006 Zobrazit plný text záznamu Full Text from ScienceDirect