Development of fiber-reinforcement-based crack arrester for composite bonded joints

• Project/Area Number: 17H03475
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Aerospace engineering
• Research Institution: The University of Tokyo
• Principal Investigator: Minakuchi Shu 東京大学, 大学院工学系研究科(工学部), 准教授 (70512359)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥15,470,000 (Direct Cost: ¥11,900,000、Indirect Cost: ¥3,570,000); Fiscal Year 2019: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2018: ¥5,460,000 (Direct Cost: ¥4,200,000、Indirect Cost: ¥1,260,000); Fiscal Year 2017: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000)
• Keywords: 複合材料 / 接着接合 / クラックアレスタ / 亀裂抑制 / 応力集中 / 剥離 / 損傷許容性 / 樹脂亀裂 / 伸張成形 / 接着 / 亀裂 / 亀裂進展抑制 / 航空宇宙工学 / 接着構造

Outline of Final Research Achievements

This study developed a fiber-reinforcement-based crack arrester technology to realize boltless composite structures. Through crack propagation tests and finite element analysis, the optimal arrester configuration for maximizing the crack stopping effect was investigated, and it was demonstrated that fatigue disbond and T-joint failure could be suppressed. In addition, ply curving termination (PCT) was devised to suppress the stress concentration at ply edges, and its effectiveness was confirmed by basic experimental verification.

Academic Significance and Societal Importance of the Research Achievements

従来の航空機複合材構造は、硬化成形した部材を接合し構造に組み立てる際に剥離防止のためのボルト締結が大量に用いられているため、複合材料の優れた力学的特性・軽量性が十分には生かされておらず、また製造コストが従来金属構造に比べて非常に高い。本研究は接着接合の信頼性を向上させることを目的とした試みであり、ボルト締結部を大幅に削減する「ボルトレス化」により軽量化と低コスト化を同時に実現するものである。

Research Products

• [Journal Article] Effect of interlocking fiber configuration on mode-I disbond arresting in composite bonded joints (2020)
  • Author(s): S. Hisada, S. Minakuchi, N. Takeda
  • Journal Title: SAMPE JOURNAL Volume: 未定
  • Peer Reviewed
• [Presentation] Ply Curving Termination to Suppress Delamination in Composite Ply Drop-Off (2019)
  • Author(s): Minakuchi S., Takeda N.
  • Organizer: The International Committee on Aeronautical Fatigue and Structural Integrity (ICAF) 2019
  • Int'l Joint Research
• [Presentation] Ply curving termination: suppressing delamination in tapered composites (2019)
  • Author(s): Shu Minakuchi, Nobuo Takeda
  • Organizer: 22nd International Conference on Composite Materials 2019
  • Int'l Joint Research
• [Presentation] Process-induced failure of deltoid in composite T-joint: fiber-optic based monitoring and numerical simulation (2019)
  • Author(s): Shinsaku Hisada, Shu Minakuchi, Nobuo Takeda
  • Organizer: 22nd International Conference on Composite Materials 2019
  • Int'l Joint Research
• [Presentation] Ply curving termination:suppressing delamination in composite ply drop-off (2019)
  • Author(s): Shu Minakuchi, Nobuo Takeda
  • Organizer: 1st Russia-Japan Joint Workshop on Composite Materials
  • Int'l Joint Research / Invited
• [Presentation] Ply Curving Terminationを用いた複合材剥離抑制 (2019)
  • Author(s): 水口周，武田展雄
  • Organizer: 第61回構造強度に関する講演会
• [Presentation] Ply Curving Terminationによるトランスバースクラックと端面剥離の抑制 (2019)
  • Author(s): 水口周，武田展雄
  • Organizer: 第 11回 日本複合材料会議
• [Presentation] CRACK PROPAGATION SUPPRESSION IN COMPOSITE T-JOINT USING FIBER-REINFORCEMENT-BASED CRACK ARRESTER (2018)
  • Author(s): Shinsaku Hisada, Shu Minakuchi and Nobuo Takeda
  • Organizer: 18th European Conference on Composite Materials
  • Int'l Joint Research
• [Presentation] 繊維強化型クラックアレスタを用いた複合材T-jointの損傷許容性向上 (2018)
  • Author(s): 久田深作，水口周，武田展雄
  • Organizer: 第60回構造強度に関する講演会
• [Presentation] Enhancing Damage Tolerance of Composite T-joint Using Fiber-Reinforcement-Based Crack Arrester (2018)
  • Author(s): Shinsaku Hisada, Shu Minakuchi, Nobuo Takeda
  • Organizer: American Society for Composites 33rd Technical Conference
  • Int'l Joint Research
• [Presentation] 繊維強化型クラックアレスタを用いた複合材T-jointの亀裂進展抑制 (2018)
  • Author(s): 久田深作, 水口周, 武田展雄
  • Organizer: 第9回日本複合材料会議
• [Presentation] Crack Propagation Suppression in Composite T-joint using Fiber-reinforcement-based Crack Arrester (2018)
  • Author(s): Shinsaku Hisada, Shu Minakuchi and Nobuo Takeda
  • Organizer: 18 European Conference on Composite Materials -ECCM 18
  • Int'l Joint Research
• [Presentation] Arresting Fatigue Crack in Composite Bonded Joint using Fiber-Reinforcement Design Feature (2017)
  • Author(s): Shu Minakuchi and Nobuo Takeda
  • Organizer: International Committee on Aeronautical Fatigue and Structural Integrity ICAF2017
  • Int'l Joint Research
• [Presentation] ARRESTING CRACK IN COMPOSITE BONDED JOINT UNDER FATIGUE USING FIBER-REINFORCEMENT-BASED FEATURE (2017)
  • Author(s): Shu Minakuchi and Nobuo Takeda
  • Organizer: SAMPE Seattle 2017
  • Int'l Joint Research
• [Presentation] ARRESTING FATIGUE CRACK IN COMPOSITE BONDED JOINT USING INTERLOCKED FIBER FEATURE (2017)
  • Author(s): Shu Minakuchi and Nobuo Takeda
  • Organizer: 21st International Conference on Composite Materials
  • Int'l Joint Research
• [Presentation] STOPPING FATIGUE CRACK IN COMPOSITE BONDED JOINT USING INTERLOCKED FIBER FEATURE (2017)
  • Author(s): Shu Minakuchi and Nobuo Takeda
  • Organizer: 15th European-Japanese Meeting on Composite Materials
  • Int'l Joint Research