Clarification of the origin of fatigue softening and one variant ωphase in binary Ti-Nb based biomaterial alloys

2012 Fiscal Year Final Research Report

• Project/Area Number: 23860030
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Structural/Functional materials
• Research Institution: Osaka University
• Principal Investigator: TODAI Mitsuharu 大阪大学, 大学院・工学研究科, 助教 (10610800)
• Co-Investigator(Renkei-kenkyūsha): NAKANO Takayoshi 大阪大学, 大学院・工学研究科, 教授 (30243182)
• Project Period (FY): 2011 – 2012
• Keywords: 生体材料 / β型Ti合金 / 単結晶 / ω相変態 / 力学特性 / 疲労試験

Research Abstract

Ti-xNb alloys have the composition dependence of the phase stability of βphase. The Ti-xNb alloy with low βphase stability exhibits anomalous temperature dependence of the electrical resistivity, low Debye temperature and elastic softening. Thus, it can be reduced the Young’s modulus by controlling βphase stability in these alloys. The βphase stability also effect on the plastic deformation in Ti-xNb alloys. The Ti-xNb alloy with low βphase stability exhibits characteristics S-S curve. This means that the ωphase is precipitated by motion of dislocation. This phenomena more clearly appear in Ti-xNb alloy single crystal by fatigue experiments. Moreover, we found that the precipitation of ωphase leads to anomalous softening.

Research Products

• [Journal Article] 生体用Ti-Nb二元系合金単結晶におけるβ相の不安定性とその基礎物性 (2013)
  • Author(s): Pan Wang, 當代光陽, 中野貴由
  • Journal Title: 日本金属学会誌 Volume: (in press)
• [Journal Article] β-Phase Instability in Binary Ti-xNb Biomaterial Single Crystals (2013)
  • Author(s): Pan Wang, Mitsuharu Todai, Takayoshi Nakano
  • Journal Title: Materials Transactions Volume: 54 Pages: 156-160
• [Journal Article] Anomalous Fatigue Behavior in Ti-Nb Single Crystal (2011)
  • Author(s): M. Todai, P. Wang, K. Hagihara and T. Nkano
  • Journal Title: Proceedings of ECO MATES Pages: 53-54
• [Presentation] 生体用Ti-xNb合金単結晶における電気抵抗とデバイ温度のNb濃度依存性 (2013)
  • Author(s): 當代光陽, Pan Wang, 中野貴由
  • Organizer: 軽金属学会
  • Place of Presentation: 富山大学
  • Year and Date: 2013-05-19
• [Presentation] 生体用Ti-Nb合金単結晶におけるω相変態とβ相の相安定性 (2013)
  • Author(s): 當代光陽, Pan Wang, 中野貴由
  • Organizer: 日本金属学会春季大会
  • Place of Presentation: 東京理科大学
  • Year and Date: 2013-03-28
• [Presentation] Effect of βphase stability on plastic deformation behavior in binary Ti-Nb biomaterial single crystals (2013)
  • Author(s): Pan Wang, 當代光陽, 中野貴由
  • Organizer: 日本金属学会春季大会
  • Place of Presentation: 東京理科大学
  • Year and Date: 2013-03-27
• [Presentation] Anomalous fatigue behavior (2011)
  • Author(s): M. Todai, Pan Wang, Koji Hagihara and Takayosi Nakano
  • Organizer: Ti-Nb single crystals International Symposium on Materials Science and Innovation on Sustainable Society
  • Place of Presentation: Osaka, Japan
  • Year and Date: 2011-11-28