宇宙科学広報・普及主幹付

後藤 健

ゴトウ ケン  (Ken Goto)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 教授
学位
博士(工学)

J-GLOBAL ID
200901053594749329
researchmap会員ID
1000227989

受賞

 1

論文

 52
  • Tran Huu Nam, Ken Goto, Yuta Tobata, Yuki Kubota, Masahito Ueda, Satoshi Kobayashi
    Journal of Composite Materials 57(5) 929-940 2023年3月  査読有り
  • Yuta Tobata, Shinsuke Takeuchi, Ken Goto
    Journal of the European Ceramic Society 41(16) 113-122 2021年12月1日  
    Stress–strain relations at different degrees of peak stress were investigated using loading–unloading tests to elucidate cumulative damage mechanisms of short fiber type C/SiC under tension. Damage observations revealed their crack length, number, and angle characteristics. Furthermore, stress–strain relations were estimated by expanding Basista's equations and by substituting measured damage characteristics into them, which revealed a nonlinear stress–strain relation. Cracks propagated in transverse fiber bundles without fiber fracture, connecting other cracks that had 75 ° – 90 ° orientation to the tensile axis. Stress–strain relations estimated qualitatively and quantitatively suggest that mixed mode I and mode II crack opening in transverse fiber bundles in the through-thickness plane caused the stress–strain nonlinear relations.
  • Yuta Tobata, Shinsuke Takeuchi, Ken Goto
    Journal of Composites Science 5(9) 2021年9月1日  
    A cumulative damage mechanism for short fiber type C/SiC during shear loading– unloading testing was examined and quantified using Iosipescu specimens parallel in the in-plane and through-thickness plane, and by using modified fracture and damage mechanics theory referring to measured damage characteristics (crack length, number and angle). A nonlinear stress–strain relation was found for both specimens. Decrease in the apparent modulus was confirmed with increased peak stress, although permanent strain increased. Inelastic strain of the decomposed tensile direction derived from shear stress was greater than that of the compressive one. Cracks propa-gated perpendicularly to the tensile direction, intruding on the boundary of the transverse fibers and connecting to other cracks. The theoretical damage mechanics model succeeded to predict the stress–strain relation, proposing that the shear mechanical properties are predictable by measuring the damage characteristics.
  • Yuta Tobata, Shinsuke Takeuchi, Ken Goto
    JOURNAL OF THE EUROPEAN CERAMIC SOCIETY 41(1) 185-193 2021年1月  
    This study investigated cumulative damage mechanisms of short fiber type C/SiC under compression. To measure mechanical properties (unloading modulus and permanent strain) before fracture, repeated loading-unloading tests were conducted using a strain gage. Damage was observed to assess characteristics of crack density, length, number, and propagation angle. Furthermore, relations between mechanical properties and damage characteristics were elucidated by application of Basista's equations and by substituting crack densities inferred from damage observations. Stress-strain relations revealed nonlinear behavior. The unloading modulus did not change, but the permanent strain increased. Cracks propagated mainly between fibers, without fiber fracture, connecting other cracks in the direction of orientation 0 deg to 30 deg to the compressive axis. We estimated permanent strain using Basista's equations and damage characteristics. Estimates roughly agreed with experiment results, suggesting that the permanent strain increase is attributable to closed crack sliding and friction caused by increased crack density.
  • Takao Nakagawa, Ken Goto, Hidehiro Kaneda, Hideo Matsuhara, Jun Matsumoto, Tadahito Mizutani, Hiroyuki Ogawa, Masaru Saijo, Yoichi Sato, Kenichiro Sawada, Hiroshi Shibai, Keisuke Shinozaki, Hiroyuki Sugita, Shinsuke Takeuchi, Chihiro Tokoku, Thierry Tirolien, Hideki Uchida
    Proceedings of SPIE - The International Society for Optical Engineering 11443 2020年  
    We present an overview of the cryogenic system of the next-generation infrared observatory mission SPICA. One of the most critical requirements for the SPICA mission is to cool the whole science equipment, including the 2.5 m telescope, to below 8 K to reduce the thermal background and enable unprecedented sensitivity in the mid- and far-infrared region. Another requirement is to cool focal plane instruments to achieve superior sensitivity. We adopt the combination of effective radiative cooling and mechanical cryocoolers to accomplish the thermal requirements for SPICA. The radiative cooling system, which consists of a series of radiative shields, is designed to accommodate the telescope in the vertical configuration. We present thermal model analysis results that comply with the requirements to cool the telescope and focal plane instruments.

MISC

 65
  • 後藤, 健, 丸, 祐介, 山田, 和彦, 志田, 真樹, 福島, 洋介, 山本, 高行, 徳留, 真一郎, 野中, 聡, 峯杉, 賢治, 竹内, 伸介, 佐藤, 泰貴, 澤井, 秀次郎, 羽生, 宏人, 阿部, 琢美, GOTO, Ken, MARU, Yusuke, YAMADA, Kazuhiko, SHIDA, Maki, FUKUSHIMA, Yosuke, YAMAMOTO, Takayuki, TOKUDOME, Shinichiro, NONAKA, Satoshi, MINESUGI, Kenji, TAKEUCHI, Shinzuke, SATO, Yasutaka, SAWAI, Shujiro, HABU, Hiroto, ABE, Takumi
    観測ロケットシンポジウム2020 講演集 = Proceedings of Sounding Rocket Symposium 2020 2021年3月  
    第3回観測ロケットシンポジウム(2021年3月24-25日. オンライン開催) 3rd Sounding Rocket Symposium (March 24-25, 2021. Online Meeting) 著者人数: 14名PDF再処理の為、2023年3月17日に差替 資料番号: SA6000162017 レポート番号: Ⅴ-3
  • 鈴木仁研, 中川貴雄, 小川博之, 北本和也, 篠崎慶亮, 竹内伸介, 内田英樹, 後藤健, 西城大, 佐藤洋一, 澤田健一郎, 東谷千比呂, 松原英雄, 松本純, 水谷忠均, 山田亨, 山村一誠, 金田英宏
    日本天文学会年会講演予稿集 2021 2021年  
  • 戸端 佑太, 後藤 健, 竹内 伸介, TOBATA Yuta, GOTO Ken, TAKEUCHI Shinsuke
    第35回宇宙構造・材料シンポジウム:講演集録 = Proceedings of 35th Symposium on Aerospace Structure and Materials 2019年12月  
    第35回宇宙構造・材料シンポジウム(2019年12月2日. 宇宙航空研究開発機構宇宙科学研究所 (JAXA)(ISAS)), 相模原市, 神奈川県資料番号: SA6000146015レポート番号: A-14
  • 宇井 恭一, 峯杉 賢治, 紙田 徹, 後藤 健, 竹内 伸介, 伊海田 皓史, 星野 剛, 坂本 満也, 佐野 成寿, 小杉 幸寛, 藤本 智也, 西尾 誠司, 日吉 誠, 迎田 健一
    宇宙科学技術連合講演会講演集 60 6p 2016年9月6日  
  • 小林 訓史, 眞保 友彰, 後藤 健, 岩田 稔
    宇宙科学技術連合講演会講演集 60 4p 2016年9月6日  

担当経験のある科目(授業)

 2

共同研究・競争的資金等の研究課題

 22