Development of Damage Model for Estimation of the Effect of Strain HIstory and Heterogeneous Microstrucure on Ductile Failure

• Project/Area Number: 24560132
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Production engineering/Processing studies
• Research Institution: Osaka University
• Principal Investigator: OHATA Mitsuru 大阪大学, 工学(系)研究科(研究院), 准教授 (20294027)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥5,460,000 (Direct Cost: ¥4,200,000、Indirect Cost: ¥1,260,000); Fiscal Year 2014: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2013: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000); Fiscal Year 2012: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
• Keywords: 延性 / 成形限界 / 損傷 / 複合組織鋼 / シミュレーション / 歪履歴依存 / 不均質組織 / 延性損傷 / ひずみ履歴 / 二相組織鋼材 / 不均質 / 損傷モデル / バウシンガー効果 / 三次元数値解析 / 福相組織鋼材 / 延性破壊限界 / 数理損傷モデル / バウシンガー特性 / 複相組織鋼材 / 延性損傷限界

Outline of Final Research Achievements

3D micro-structural FE-model was developed for analyzing the stress/strain localization behaviors by micro-structural strength mismatch. Ductile damage model for reproducing damage evolution up to micro-void/micro-crack formation was also propsed taking the "Baushinger effect" of the materials into account. The combination of the 3D micro-structural FE-model and the proposed numerical damge model was verified to predtic effect of strain history and volume fraction of a second phase of two-phase steel on dcutile fracture limit. This numeriacl simulation was found to correlate micro-structural characteristics with mechanical properties including stress-strain curve and strain history effect on dcutile failure of two-phase steel.

Research Products

• [Journal Article] Simulation-based method for hierarchal material design to improve ductile crack growth resistance of structural component (2015)
  • Author(s): Hiroto Shoji, Mitsuru Ohata and Fumiyoshi Minami
  • Journal Title: International Journal of Fracture Volume: 192 Issue: 2 Pages: 167-178
  • DOI: 10.1007/s10704-015-9993-5
  • Peer Reviewed
• [Journal Article] 延性き裂進展抵抗を支配する材料延性に及ぼす不均質組織特性の影響予測 －複相組織材料の延性予測－ (2014)
  • Author(s): 庄司博人，大畑 充，南二三吉
  • Journal Title: 鉄と鋼 Volume: 100 Pages: 668-677
  • NAID: 130004747772
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] 組織不均質を考慮した三次元延性損傷シミュレーション法 －複相組織材料の延性予測－ (2013)
  • Author(s): 大畑 充，庄司博人，南二三吉
  • Journal Title: 鉄と鋼 Volume: Vol.99, No. 9 Pages: 573-581
  • NAID: 130003372561
  • Peer Reviewed
• [Journal Article] Effect of Mechanical Properties on Tensile Strain Limit for Leakage of High-Pressure Pipe with Surface Crack (2012)
  • Author(s): Mitsuru Ohata, Yusuke Takada, Takahiro Sakimoto, Satoshi Igi, Shigeru Endo and Fumiyoshi Minami
  • Journal Title: International Journal of Offshore and Polar Engineering Volume: 22 Pages: 157-164
  • Peer Reviewed
• [Presentation] Hierarchical Ductile Damage Simulation for Structural Performance-Based Material Design (2014)
  • Author(s): Mitsuru Ohata
  • Organizer: 4th International Symposium on Steel Science (ISSS2014)
  • Place of Presentation: Kyoto, Japan
  • Year and Date: 2014-11-03 – 2014-11-06
  • Invited
• [Presentation] Hierarchical Damage Simulation for Structural Performance-Based Material Design (2014)
  • Author(s): Mitsuru Ohata
  • Organizer: The 4th East Asia Symposium on Technology of Welding & Joining (4th EAST-WJ)
  • Place of Presentation: Xi’an, China
  • Year and Date: 2014-10-21 – 2014-10-23
  • Invited
• [Presentation] Numerical simulation of flat-to-slant ductile fracture transition in notched plate (2014)
  • Author(s): Mitsuru Ohata
  • Organizer: 20th European Conference on Fracture (ECF20)
  • Place of Presentation: Trondheim, Norway
  • Year and Date: 2014-07-01 – 2014-07-03
• [Presentation] Hierarchical Damage Simulation to Correlate Micro-structural Characteristics of Steel with Ductile Crack Growth Resistance of Component (2013)
  • Author(s): Mitsuru Ohata, Hiroto Shoji, Fumiyoshi Minami
  • Organizer: International Conference on Fracture,
  • Place of Presentation: Beijing, China
• [Presentation] 二相組織鋼の強度・延性に及ぼす組織性状の影響
  • Author(s): 庄司 博人，大畑 充，南 二三吉
  • Organizer: （一社）溶接学会
  • Place of Presentation: 岡山理科大学
• [Presentation] 延性き裂進展抵抗に及ぼす材料組織形態の影響
  • Author(s): 大畑充
  • Organizer: （社）日本鉄鋼協会
  • Place of Presentation: 愛媛大学
  • Invited