Microstructural characterization of the Mixed-material deposition layer by using the advanced nano-fabrication technique

2013 Fiscal Year Final Research Report

• Project/Area Number: 23760811
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Nuclear fusion studies
• Research Institution: National Institute for Fusion Science
• Principal Investigator: TOKITANI Masayuki 核融合科学研究所, ヘリカル研究部, 助教 (30455208)
• Project Period (FY): 2011 – 2013
• Keywords: プラズマ・壁相互作用 / Mixed-material / 再堆積層 / 微細構造観察 / 電子顕微鏡 / ナノ機械的特性評価 / プラズマ粒子

Research Abstract

Toroidal profiles of the microscopic damage, erosion and deposition on the Large Helical Device (LHD) first-wall (SUS316L) were simultaneously evaluated by using focused ion beam (FIB) fabrication technique and transmission electron microscope (TEM) observation.
Sputtering erosion of the first-wall surfaces was mainly caused by glow discharge cleanings (GDCs) and not main plasma discharges, and the erosion depths of each toroidal section were varied from 50 nm to 1000 nm. Characteristics of the deposition layers and microscopic damages on the SUS316L matrix were different in each toroidal section. If we would want to reduce the amount of the hydrogen isotope retention on the first-wall surface, suppression of the formation of the mixed-material deposition layer is necessary.

Research Products

• [Journal Article] Evaluation of the surface morphologies and erosion/deposition profiles on the LHD first-wall by using toroidal array probes (2013)
  • Author(s): M. Tokitani, S. Masuzaki, N. Yoshida, T. Akiyama, N. Noda, A. Sagara, H. Yamada, T. Muroga, LHD experiment group, S. Nagata, B. Tsuchiya
  • Journal Title: Journal of Nuclear Materials Volume: 442 Pages: S873-S879
  • Peer Reviewed
• [Journal Article] Microstructural characterization of mixed-material deposition layer on the LHD divertor tiles by using nano-geological diagnosis (2013)
  • Author(s): M. Tokitani, S. Masuzaki, N. Yoshida, A. Sagara, N. Noda, H. Yamada, LHD Experiment Group
  • Journal Title: Journal of Nuclear Materials Volume: 438 Pages: S818-S821
  • Peer Reviewed
• [Journal Article] ITERに向けたタングステンPWI研究の進展と課題 (2011)
  • Author(s): 時谷政行,上田良夫
  • Journal Title: Journal of Plasma and Fusion Research Volume: Vol.87, No.9 Pages: 591-599
• [Journal Article] Exfoliation of the tungsten fibreform nanostructure by unipolar arcing inthe LHD divertor plasma (2011)
  • Author(s): M. Tokitani, S. Kajita, S. Masuzaki, Y. Hirahata, N. Ohno, T. Tanabe, LHD Experiment Group
  • Journal Title: Nuclear Fusion Volume: 51 Pages: 102001
  • Peer Reviewed
• [Journal Article] Micro/nano structural analysis of mixed-material deposition layer formed on the first walls of large helical device (2011)
  • Author(s): M. Tokitani, N. Yoshida, S. Masuzaki, N. Ashikawa, A. Sagara, N. Noda, H. Yamada, LHD Experiment Group
  • Journal Title: Journal of Nuclear Materials Volume: 417 Pages: 668-672
  • Peer Reviewed
• [Presentation] LHD高性能定常放電におけるプラズマ壁相互作用 (2013)
  • Author(s): 時谷政行,上田良夫,吉田直亮,増﨑貴,笠原寛史,吉村泰夫,長崎百伸,芦川直子,武藤敬,LHD実験グループ
  • Place of Presentation: 東京都目黒区
  • Year and Date: 20131203-06
• [Presentation] ヘリウムプラズマ照射とMixed-material堆積層形成による核融合装置プラズマ対向材料の表面変質とそれらが燃料粒子捕捉特性へ与える影響 (2012)
  • Author(s): 時谷政行
  • Organizer: プラズマ核融合学会第29回年会
  • Place of Presentation: 福岡県春日市(受賞講演)
  • Year and Date: 20121127-30
• [Presentation] LHDプラズマ照射によるナノ構造タングステン上でのユニポーラアーキングの発生 (2012)
  • Author(s): 時谷政行,梶田信,増崎貴,平畑祐樹,大野哲靖,田辺哲朗,LHD実験グループ
  • Organizer: 第9回核融合エネルギー連合講演会
  • Place of Presentation: 兵庫県神戸市
  • Year and Date: 20120628-29
• [Presentation] Microstructural characterization of mixed-material deposition layer on the LHD divertor tiles by using nano-geological diagnosis (2012)
  • Author(s): M. Tokitani, S. Masuzaki, N. Yoshida, A. Sagara, N. Noda, H. Yamada, LHD experiment group
  • Organizer: 20th International Conference on Plasma Surface Interactions
  • Place of Presentation: Aachen, Germany
  • Year and Date: 20120521-25
• [Presentation] Change of surface morphology and particle retention of the plasma facing materials in the fusion devices under helium irradiation and formation of the mixed-material deposits (2011)
  • Author(s): M. Tokitani, S. Masuzaki, N. Yoshida, N. Noda, S. Kajita, N. Ohno, A. Sagara, H. Yamada, LHD Experiment Group
  • Organizer: Plasma Conference 2011
  • Place of Presentation: Kanazawa, Ishikawa, Japan
  • Year and Date: 20111122-25
• [Presentation] Evaluation of the microscopic damage and erosion/deposition profiles on the LHD first-wall by using toroidal array probes (2011)
  • Author(s): M. Tokitani, N. Yoshida, S. Masuzaki, N. Noda, A. Sagara, H. Yamada, LHD Experiment Group, S. Nagata, B. Tsuchiya
  • Organizer: 15th International Conference on Fusion Reactor Materials
  • Place of Presentation: Charleston, South Carolina, USA
  • Year and Date: 20111016-22
• [Remarks]
  • URL: http://dpc.nifs.ac.jp/FSYS-HP/tokitani/tokitani.html