Mechanical Characterization of grain boundary strengthening through TEM in-situ indentation

• Project/Area Number: 23560852
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: National Institute for Materials Science
• Principal Investigator: OHMURA TAKAHITO 独立行政法人物質・材料研究機構, 構造材料ユニット, グループリーダー (40343884)
• Project Period (FY): 2011 – 2013
• Project Status: Completed (Fiscal Year 2013)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2012: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2011: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: ナノインデンテーション / 転位 / 粒界 / TEM / 力学特性 / 結晶粒微細化強化 / ＴＥＭ

Research Abstract

TEM in-situ compression test was performed for Fe-Si bicrystal and revealed that dislocations passed through grain boundary without any pile-up. These results suggest that dislocation reaction occurs at grain boundary. We observed two types of dislocations of screw and edge during deformation. Load-displacement curves obtained with TEM observation shows that screw type dominant with lower mobility corresponds to higher flow stress. Another data shows obvious yield phenomenon and subsequently remarkable strain softening. In that case, dislocation density increases with strain after yielding. For the quantitative relationship between the flow stress and dislocation density is understood in the Johnston Gilman model

Research Products

• [Journal Article] Plasticity initiation and evolution during nanoindentation of an iron–3% silicon single crystal (2014)
  • Author(s): L. Zhang and T. Ohmura
  • Journal Title: Phys. Rev. Lett Volume: 112 Pages: 145504-145504
• [Journal Article] Plasticity initiation and evolution during nanoindentation of an iron–3% silicon single crystal (2014)
  • Author(s): L. Zhang and T. Ohmura
  • Journal Title: Phys. Rev. Lett. Volume: 112 Issue: 14
  • DOI: 10.1103/physrevlett.112.145504
  • Peer Reviewed
• [Journal Article] Dislocation character transition and related mechanical response in a body centered cubic single crystal (2012)
  • Author(s): L. Zhang, T. Ohmura, K. Sekido, T. Hara, K. Nakajima, K. Tsuzaki
  • Journal Title: Scripta Mater. Volume: 67 Pages: 388-391
• [Journal Article] Effects of lattice defects on indentation-induced plasticity initiation behavior in metals (2012)
  • Author(s): T. Ohmura, L. Zhang, K. Sekido and K. Tsuzaki
  • Journal Title: J. Mater. Res. Volume: 27 Pages: 1742-1749
• [Journal Article] Effect of Dislocation Density on Initiation of Plastic Deformation on Fe-C Steels (2012)
  • Author(s): K. Sekido, T. Ohmura, T. Hara and K. Tsuzaki
  • Journal Title: Mater. Trans. Volume: 53 Pages: 907-912
  • NAID: 10030629487
• [Journal Article] Effects of lattice defects on indentation-induced plasticity initiation (2012)
  • Author(s): T.Ohmura L.Zhang K.Sekido K.Tsuzaki
  • Journal Title: International Journal of Materials Research Volume: Vol.7/Number 13 Issue: 13 Pages: 1742-1749
  • DOI: 10.1557/jmr.2012.161
  • Peer Reviewed
• [Journal Article] Dislocation character transition and related mechanical response in a body centered cubic single crystal (2012)
  • Author(s): L.Zhang T.Ohmura K.Sekido T.Hara K.Nakajima K.Tsuzaki
  • Journal Title: Scripta Materialia Volume: Vol.67/Issue4 Issue: 4 Pages: 388-391
  • DOI: 10.1016/j.scriptamat.2012.05.032
• [Journal Article] Effects of lattice defects on indentation-induced plasticity initiation behavior in metals (2012)
  • Author(s): T. Ohmura, L. Zhang, K. Sekido and K. Tsuzaki
  • Journal Title: Journal of Materials Research Volume: 印刷中
  • Peer Reviewed
• [Journal Article] The effect of interstitial carbon on the initiation of plastic deformation of steels (2011)
  • Author(s): K. Sekido, T. Ohmura, L. Zhang, T. Hara and K. Tsuzaki
  • Journal Title: Mater. Sci. Eng. Volume: A 530 Pages: 396-401
• [Journal Article] Nanoindentation/atomic force microscopy analysis of e-martensitic transformation and shape memory effect in Fe-28Mn-6Si-5Cr alloy (2011)
  • Author(s): K. Sekido, T. Ohmura, T. Sawaguchi, M. Koyama, H.W. Park and K. Tsuzaki
  • Journal Title: Scripta Mater. Volume: 65 Pages: 942-945
• [Journal Article] Direct observation of plastic deformation in iron-3% silicon single crystal by in situ nanoindentation in transmission electron microscopy (2011)
  • Author(s): Ling Zhang, Takahito Ohmura, Kaoru Sekido, Kiyomi Nakajima, Toru Hara and Kaneaki Tsuzaki
  • Journal Title: Scripta Mater. Volume: 64 Pages: 919-922
• [Journal Article] Direct observation of plastic softening with increasing dislocation density in steel
  • Author(s): L. Zhang, N. Sekido and T. Ohmura
  • Journal Title: Mater. Sci. Eng., A Volume: (Accepted)
• [Presentation] 「固溶元素と転位の相互作用」 (2014)
  • Author(s): 大村孝仁,張鈴,鈴木拓也,関戸信彰,津崎兼彰
  • Organizer: 日本金属学会2014春季講演大会
  • Place of Presentation: 東京
  • Year and Date: 2014-03-21
• [Presentation] 「局所力学挙動評価による粒界近傍の変形挙動解析」 (2013)
  • Author(s): 大村孝仁
  • Organizer: 日本鉄鋼協会自主フォーラム「鉄鋼材料の結晶界面物性とその制御」
  • Place of Presentation: 東京
  • Year and Date: 2013-11-19
• [Presentation] Nano-scale Deformation Behavior of Metals Associated with Various Lattice Defects (2013)
  • Author(s): T.Ohmura
  • Organizer: International Workshop on Advancing Materials Performance from the Nanoscale
  • Place of Presentation: Xi'an
  • Year and Date: 2013-06-12
• [Presentation] Nanoindentation-induced deformation behavior of metals (2013)
  • Author(s): T.Ohmura
  • Organizer: 1st Workshop of Science and Technology of Materials Science
  • Place of Presentation: Gyeongsan
  • Year and Date: 2013-05-09
• [Presentation] 「局所力学特性評価による粒界近傍の変形挙動解析」 (2013)
  • Author(s): 大村孝仁
  • Organizer: 日本鉄鋼協会自主フォーラム「鉄鋼材料の結晶界面物性とその制御」
  • Place of Presentation: 東京
  • Year and Date: 2013-01-17
• [Presentation] Advanced Techniques of Microstructural and Mechanical Characterization in Nano-scale for Structural Materials (2013)
  • Author(s): T. Ohmura
  • Organizer: TNU-NIMS Workshop
  • Place of Presentation: Taipei
  • Year and Date: 2013-01-09
• [Presentation] Nano-scale Deformation Behavior of Metals Associated with Various Lattice Defects (2013)
  • Author(s): T. Ohmura
  • Organizer: 2013 International Workshop on Advancing Materials Performance from the Nanoscale
  • Place of Presentation: Xi'an
  • Invited
• [Presentation] 「ナノインデンテーションによる降伏現象の素過程解析」 (2012)
  • Author(s): 大村孝仁
  • Organizer: 日本鉄鋼協会計算工学による組織と特性予測II研究会
  • Place of Presentation: 東海市
  • Year and Date: 2012-06-11
• [Presentation] 「鉄鋼材料の局所力学挙動解析による強化機構解析」 (2012)
  • Author(s): 大村孝仁
  • Organizer: 日本金属学会2012年春季大会
  • Place of Presentation: 横浜
  • Year and Date: 2012-03-28
• [Presentation] TEM in-situナノインデンテーション法の応用 (2012)
  • Author(s): 大村孝仁
  • Organizer: 日本顕微鏡学会第68回学術講演会
  • Place of Presentation: つくば国際会議場（つくば市）
• [Presentation] Indentation-induced plasticity of metals with various lattice defects (2012)
  • Author(s): 大村孝仁
  • Organizer: IUMRS-ICEM 2012
  • Place of Presentation: パシフィコ横浜（横浜市）
• [Presentation] 鉄鋼材料の局所力学挙動評価による強化機構解析 (2012)
  • Author(s): 大村孝仁
  • Organizer: 日本金属学会2012年春季大会(招待講演)
  • Place of Presentation: 横浜国立大学（神奈川県）
• [Presentation] Indentation-induced deformation behavior in the vicinity of grain boundary of Fe alloys (2011)
  • Author(s): T. Ohmura
  • Organizer: MS&T, Columbus
  • Place of Presentation: Ohio
  • Year and Date: 2011-10-09
• [Presentation] Investigation on a fundamental deformation behavior through nanoindentation technique (2011)
  • Author(s): T. Ohmura
  • Organizer: The Fourth International Indentation workshop
  • Place of Presentation: Seoul
  • Year and Date: 2011-07-03
• [Presentation] 粒界近傍における局所領域変形挙動の解析 (2011)
  • Author(s): 大村孝仁
  • Organizer: 日本鉄鋼協会第162回秋季講演大会(招待講演)
  • Place of Presentation: 大阪大学（大阪府）
• [Presentation] 鉄合金における種々の格子欠陥と塑性変形開始挙動の関係 (2011)
  • Author(s): 大村孝仁
  • Organizer: 高温強度と組織形成の材料科学研究会(招待講演)
  • Place of Presentation: 樺川荘（香川県）
• [Book] ナノインデンテーション法による局所力学挙動解析 (2013)
  • Author(s): 大村孝仁
  • Publisher: 軽金属
• [Book] 局所力学挙動解析による機械的特性の評価技術ナノスケールからの変形機構の素過程に迫る (2013)
  • Author(s): 大村孝仁
  • Publisher: 塑性と加工
• [Book] 高強度マルテンサイト鋼の強化機構解析の新展開 (2011)
  • Author(s): 大村孝仁
  • Publisher: 金属
• [Remarks]
  • URL: http://www.nims.go.jp/group/sdg/result.html
• [Remarks] なし