Deep deuterium retention and Be/W mixing at tungsten coated surfaces in the JET divertorVise andre og tillknytning
2016 (engelsk)Inngår i: Physica Scripta, ISSN 0031-8949, E-ISSN 1402-4896, Vol. T167, artikkel-id 014061Artikkel i tidsskrift (Fagfellevurdert) Published
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Abstract [en]
Surface samples from a full poloidal set of divertor tiles exposed in JET through operations 2010-2012 with ITER-like wall have been investigated using SEM, SIMS, ICP-AES analysis and micro beam nuclear reaction analysis (μ-NRA). Deposition of Be and retention of D is microscopically inhomogeneous. With careful overlaying of μ-NRA elemental maps with SEM images, it is possible to separate surface roughness effects from depth profiles at microscopically flat surface regions, without pits. With (3He, p) μ-NRA at 3-5 MeV beam energy the accessible depth for D analysis in W is about 9 μm, sufficient to access the W/Mo and Mo/W interfaces in the coatings and beyond, while for Be in W it is about 6 μm. In these conditions, at all plasma wetted surfaces, D was found throughout the whole accessible depth at concentrations in the range 0.2-0.7 at% in W. Deuterium was found to be preferentially trapped at the W/Mo and Mo/W interfaces. Comparison is made with SIMS profiling, which also shows significant D trapping at the W/Mo interface. Mixing of Be and W occurs mainly in deposited layers.
sted, utgiver, år, opplag, sider
Institute of Physics Publishing (IOPP), 2016. Vol. T167, artikkel-id 014061
Emneord [en]
beryllium, deuterium, ion beam analysis, materials migration, Atomic emission spectroscopy, Ion beams, Mixing, Nuclear reactions, Surface roughness, Coated surface, Deposited layer, Deuterium retention, Nuclear reaction analysis, Surface roughness effects, Surface sample, Wetted surface, Fighter aircraft
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Identifikatorer
URN: urn:nbn:se:kth:diva-188322DOI: 10.1088/0031-8949/T167/1/014061ISI: 000383504700062Scopus ID: 2-s2.0-84959887762OAI: oai:DiVA.org:kth-188322DiVA, id: diva2:936256
Konferanse
15th International Conference on Plasma-Facing Materials and Components for Fusion Applications, PFMC 2015, Aix-en-Provence, France, 18 May 2015 through 22 May 2015
Merknad
QC 20161024
2016-06-132016-06-092024-03-15bibliografisk kontrollert