@misc{oai:repo.qst.go.jp:00066799,
 author = {Asakura, Nobuyuki and Masuzaki, S. and Tokitani, M. and Ashikawa, N. and Otsuka, T. and Oya, Y. and Hatano, Y. and Miyamoto, M. and Sakamoto, R. and Sakurada, S. and Uemura, Y. and Azuma, K. and Yumizuru, K. and Isobe, Kanetsugu and Oyaizu, Makoto and Suzuki, Tatsuya and Kurotaki, Hironori and Hamaguchi, Dai and Hayashi, Takumi and Widdowson, A. and Rubel, M. and Heinola, K. and Jachmich, S. and Likonen, J. and Grzonka, J. and 朝倉 伸幸 and 磯部 兼嗣 and 小柳津 誠 and 鈴木 達也 and 黒滝 宏紀 and 濱口 大 and 林 巧},
 month = {Sep},
 note = {Comprehensive analysis of the divertor tile surface and dust produced by the 1st campaign (2011-2012) of the JET ITER-Like-Wall (ILW) experiment has been performed in QST Rokkasho as a part of the Broader Approach (BA) DEMO R&D activity. The R&D facility is a unique facility where tritium, beryllium and activation materials can be handled. Plasma-Wall-Interaction analyses on these samples were carried out by NIFS, universities and QST collaboration with strong support by JET and EU. Microstructure, atomic composition and chemical states of the surfaces on the tiles and dust have been analysed. The divertor target in JET-ILW is made partly of tungsten (W) bulk lamellar plates and mainly of W-coating on the carbon fiber composite (CFC) bulk tiles by Vacuum Plasma Spray (VPS) process. In this analysis, W-coating tile samples (diameter of 17mm) were used, retracted from the inboard and outboard vertical targets and at the divertor floor. Two bottles of dust samples were collected by a vacuum cleaner on the inner and oud outer divertor surfaces. In JET-ILW, most of the first wall surface is covered by Be, and Be impurity is transported with the plasma from the first wall to the divertor with repeating the deposition and erosion processes.
Recently, some unique analysis results were obtained, in addition to standard surface analysis. Microstructure analysis of tile and dust cross-sections as well as their surfaces have been performed, using a transmission electron microscope (TEM) after the focused ion beam (FIB) fabrication. In particular, in the thick Be-deposition layers on the inner W-target, nano-size bubbles-like structure was generated, and the deposition layers were composed by mixture of W, Be, C, Ni and O, evaluated by using X-ray photoelectron spectroscopy (XPS) and Electron Probe Micro Analyzer (EPMA). These deposition layers might be affected by various plasma operations in the experiment campaign. Local pattern of the Be-deposition on a rough VPS-W surface against the plasma incident angle was investigated. The micro-structure analysis of dust particles showed that bubble-like structure was also generated inside a Be dominant dust (large 100 μm size dusts were so far analyzed), and chemical components and state analysis showed that BeO in a Be dominant dusts and some W and/or C dusts were determined. The analysis method of the tile and dust samples were established. Evaluations of hydrogen isotope retention and Tritium-specific activity (Bq/g) in JET-ILW tile surface and dust particles will be also presented., 13th International Workshop on Beryllium Technology},
 title = {Broader Approach (BA) R&D research status of the JET-ILW divertor tile and dust in Rokkasho: relating to Be deposition study},
 year = {2017}
}