Fuel retention in carbon materials under ITER-relevant mixed species plasma conditions
2009 (English)In: Physica scripta. T, ISSN 0281-1847, Vol. T138, 014012- p.Article in journal (Refereed) Published
Samples of CFC NB41 and fine-grain graphite ATJ have been exposed to PISCES plasmas containing (i) pure deuterium, (ii) deuterium and beryllium, (iii) deuterium, beryllium and helium, and (iv) deuterium, beryllium and argon. Thermal desorption spectrometry (TDS) and nuclear reaction analysis (NRA) have been used to measure the amount and distribution of retained deuterium in the samples. For the case of pure deuterium plasma, parametric studies of deuterium retention in NB41 have been done with variations of the incident deuterium fluence (Phi = 1 x 10(25)-5 x 10(26) m(-2)), ion energy (E-i = 20-120 eV) and sample surface temperature (T-s = 370-820 K). It has been found, that for T-s = 470K the retention scales as Phi(0.35). For T-s = 820K the retention saturates at a level of similar to 10(21) Dm(-2). The retention increases with E-i and drops with higher T-s. At T-s = 720 K, the beryllium seeding results in a building of a protective beryllium carbide layer, which appears to prevent the in-bulk diffusion of deuterium, thus reducing the retention. Admixture of Ar and, in the case of low E-i, He leads to a significant reduction of the retention.
Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2009. Vol. T138, 014012- p.
DEUTERIUM RETENTION, GRAPHITE, HYDROGEN, BERYLLIUM
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:kth:diva-25571DOI: 10.1088/0031-8949/2009/T138/014012ISI: 000273199200013ScopusID: 2-s2.0-77953883206OAI: oai:DiVA.org:kth-25571DiVA: diva2:371028
12th International Workshop on Plasma-Facing Materials and Components for Fusion Applications Julich, GERMANY, MAY, 2009
QC 201011182012-01-232010-10-272012-01-23Bibliographically approved