Innovation of bulk nano-structured commercial purity Ti with utra-high strength and high ductility utilizing TWIP effect

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H03409
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Kanazawa University
• Principal Investigator: WATANABE Chihiro 金沢大学, 機械工学系, 教授 (60345600)
• Co-Investigator(Kenkyū-buntansha): 三浦 博己 豊橋技術科学大学, 工学(系)研究科(研究院), 教授 (30219589) ; 都留 智仁 国立研究開発法人日本原子力研究開発機構, 原子力科学研究部門 原子力科学研究所 原子力基礎工学研究センター, 研究職 (80455295)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 工業用純チタン / 巨大ひずみ加工 / バルクナノメタル / 生体用インプラント

Outline of Final Research Achievements

Microstructure and mechanical properties of ultrafine-grained bulk nano-structured commercial purity titanium (BN-Ti) were systematically investigated. It was clarified that the larger the pass strain during the multi-directional forging processing, the finer the grains, and the higher the strength. The deformation mechanism of the BN-Ti transitions from "prismatic slip + pyramidal slip" to "prismatic slip + deformation twinning" as the grain size increases. The deformation mechanisms were also discussed from the viewpoint of computational mechanics.
The BN-Ti has attractive properties as a biomaterial. The surface treatments of BN-Ti were carried out, and the biological contact behavior of the bone cells was investigated. The BN-Ti after the surface treatments exhibited that the contact angle of bone cells was extremely small and the biological reaction was superior, compared with the conventional commercial purity Ti.

Free Research Field

金属材料工学

Academic Significance and Societal Importance of the Research Achievements

BN-Tiの変形メカニズムの結晶粒径依存性，及び変形メカニズムに与える微量元素の効果について，実験的・計算機理学的な検討から，系統的に明らかにする事ができた．得られた結果を作製プロセスへフィードバックすることで，BN-Tiの合金設計・創造プロセスへの指導原理を構築することができた．さらに，骨細胞との生体反応を調査し，市販Tiよりも優れていることも示し，生体用インプラントへの応用の可能性も示した．