Ion beam analysis of tungsten layers in EUROFER model systems and carbon plasma facing components
2015 (English)In: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, ISSN 0168-583X, E-ISSN 1872-9584Article in journal (Refereed) Published
The tungsten enriched surface layers in two fusion-relevant EUROFER steel model samples, consisting of an iron-tungsten mixture exposed to sputtering by deuterium ions, were studied by Rutherford backscattering spectrometry and medium energy ion scattering. Despite very different exposure parameters (in particular a two orders of magnitude difference in ion fluence), the total amount of tungsten atoms per unit area in the enriched layers were similar for the two samples (2·1015 and 2.4·1015 atoms/cm2 respectively). A depth profile featuring exponential decrease in tungsten content towards higher depths with 10-20at.% of tungsten at the surface and a decay constant between 0.05 and 0.08Å-1 was indicated in one sample, whereas only the total areal density of tungsten atoms was measured in the other. In addition, two different beams, iodine and chlorine, were employed for elastic recoil detection analysis of the deposited layer on a polished graphite plate from a test limiter in the TEXOR tokamak following experiments with tungsten hexafluoride injection. The chlorine beam was preferred for tungsten analysis, mainly because it (as opposed to the iodine beam) does not give rise to problems with overlap of forward scattered beam particles and recoiled tungsten in the spectrum.
Place, publisher, year, edition, pages
ERDA, EUROFER, Fusion, MEIS, Tungsten, Atoms, Carbon, Chlorine, Forward scattering, Fusion reactions, Iodine, Ion beams, Ions, Magnetoplasma, Rutherford backscattering spectroscopy, Elastic recoil detection analysis, Exposure parameters, Medium energy ion scattering, Orders of magnitude, Rutherford back-scattering spectrometry
IdentifiersURN: urn:nbn:se:kth:diva-177225DOI: 10.1016/j.nimb.2015.09.024ISI: 000373412000071ScopusID: 2-s2.0-84960241915OAI: oai:DiVA.org:kth-177225DiVA: diva2:873938
QC 201511252015-11-252015-11-172016-05-03Bibliographically approved