First results and surface analysis strategy for plasma-facing components after JET operation with the ITER-like wall

TY - JOUR

T1 - First results and surface analysis strategy for plasma-facing components after JET operation with the ITER-like wall

AU - Likonen, J.

AU - Alves, E.

AU - Baron-Wiechec, A.

AU - Brezinsek, S.

AU - Coad, J. P.

AU - Hakola, A.

AU - Heinola, K.

AU - Koivuranta, S.

AU - Matthews, G. F.

AU - Petersson, P.

AU - Rubel, M.

AU - Stan-Sion, C.

AU - Widdowson, A.

PY - 2014

Y1 - 2014

N2 - During the carbon wall operations of JET since 2001, an extensive post-mortem analysis programme has been carried out under the JET Task Force Fusion Technology and a similar analysis programme is underway for the JET-ILW tiles removed during the 2012 shutdown. The first post-mortem results from the JET ITER-like wall tiles have shown that the overall amount of deposition on the divertor tiles and on remote divertor areas has been reduced by more than an order of magnitude with respect to JET-C. In addition, the obtained data indicate a possible interaction between Be and W such as the formation of mixed Be-W layers. This could be due to the surface roughness of the tiles, or could be caused by diffusion or even alloying. Ion-beam analyses and secondary ion mass spectrometry techniques give only elemental information, so other techniques such as x-ray diffraction, x-ray photoelectron spectroscopy, secondary electron microscopy/energy dispersive x-ray spectroscopy and nuclear microprobing are required. Since the nature of deposition and erosion has changed during the JET-ILW operations, a change in the post-mortem analysis programme is needed. For example, no cross-sectional samples from the sloping parts of tiles 4 and 6 are required. A strategy for post-mortem analyses of the marker-coated tiles will be presented in this paper.

AB - During the carbon wall operations of JET since 2001, an extensive post-mortem analysis programme has been carried out under the JET Task Force Fusion Technology and a similar analysis programme is underway for the JET-ILW tiles removed during the 2012 shutdown. The first post-mortem results from the JET ITER-like wall tiles have shown that the overall amount of deposition on the divertor tiles and on remote divertor areas has been reduced by more than an order of magnitude with respect to JET-C. In addition, the obtained data indicate a possible interaction between Be and W such as the formation of mixed Be-W layers. This could be due to the surface roughness of the tiles, or could be caused by diffusion or even alloying. Ion-beam analyses and secondary ion mass spectrometry techniques give only elemental information, so other techniques such as x-ray diffraction, x-ray photoelectron spectroscopy, secondary electron microscopy/energy dispersive x-ray spectroscopy and nuclear microprobing are required. Since the nature of deposition and erosion has changed during the JET-ILW operations, a change in the post-mortem analysis programme is needed. For example, no cross-sectional samples from the sloping parts of tiles 4 and 6 are required. A strategy for post-mortem analyses of the marker-coated tiles will be presented in this paper.

KW - JET ITER-like wall

KW - beryllium

KW - surface analysis

KW - tungsten

UR - http://www.scopus.com/inward/record.url?scp=84902215772&partnerID=8YFLogxK

U2 - 10.1088/0031-8949/2014/T159/014016

DO - 10.1088/0031-8949/2014/T159/014016

M3 - 会议文章

AN - SCOPUS:84902215772

SN - 0281-1847

VL - T159

JO - Physica Scripta

JF - Physica Scripta

M1 - 014016

T2 - 14th International Conference on Plasma-Facing Materials and Components for Fusion Applications, PFMC 2013

Y2 - 13 May 2013 through 17 May 2013

ER -