New Biomaterial -Development of Co-based Superelastic Alloy-

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K18933
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 26:Materials engineering and related fields
• Research Institution: Tohoku University
• Principal Investigator: Omori Toshihiro 東北大学, 工学研究科, 准教授 (60451530)
• Project Period (FY): 2018-06-29 – 2020-03-31
• Keywords: 生体材料 / 形状記憶合金 / 超弾性 / マルテンサイト変態 / コバルト合金 / コバルトクロム合金

Outline of Final Research Achievements

In this study, the composition range of the BCC single phase at 1200C was determined in the Co-Cr-Al-Si system. The composition dependence of the martensitic transformation temperatures and Curie temperature of the parent phase were also determined. Using these results, the alloy composition for superelastic alloy was selected. A compressive superelastic test was conducted in Co-Cr-Al-Si single crystal and good superelasticity was obtained. Anomalous negative temperature dependence of the critical stress for martensitic transformation was observed. It was found in this study that Co-Cr superelastic alloy with good corrosion resistance is promising for a new biomaterial.

Free Research Field

金属材料学

Academic Significance and Societal Importance of the Research Achievements

本研究では、新しいCo-Cr-Al-Si系超弾性合金の研究を行い、その合金設計の基礎情報を得たことは今後の材料開発にとって重要である。さらに、設計した合金で超弾性試験を行い、明確な超弾性が得られることも実証できた。比較的高いCr濃度を有する本Co-Cr-Al-Si合金は耐食性に優れることも確認でき、新しい生体用超弾性として有望であると考えられる。