Development of high-strength titanium alloys and artificial hip joint by additive manufacturing

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05061
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26040:Structural materials and functional materials-related
• Research Institution: Tottori University
• Principal Investigator: Chen Zhong-Chun 鳥取大学, 工学研究科, 教授 (00282111)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: チタン / 積層造形 / 酸素 / 固溶強化 / 強度 / 人工股関節 / インプラント / 生体適合性

Outline of Final Research Achievements

A mixture of titanium powder and a small amount of oxide powder was used as a starting material, which was processed by a selective laser melting (SLM) method. The effect of oxide addition on microstructure and mechanical properties of the as-built samples has been investigated. The strength and hardness were significantly enhanced, even higher than those of Ti-6Al-4V alloy, due to solid solution strengthening of oxygen and other atoms formed through decomposition of the oxide during SLM process and microstructural refinement by rapid solidification. In addition, the needle-like microstructure also contributes to high ductility, making it possible to achieve both high strength and high ductility.

Free Research Field

材料工学、材料加工学

Academic Significance and Societal Importance of the Research Achievements

チタンに酸素を添加すると、強度の向上が知られているが、延性の著しい低下を招く。本研究では、金属3Dプリンタを駆使して高強度・高延性かつ優れた生体適合性を有する高酸素チタン合金の作製が可能となった。これにより、次世代カスタムメイドインプラント等医用分野のみならず、将来、航空機や自動車部品にもTi-6Al-4V合金の代替材料としての応用が可能であり、実用的にも大きな波及効果が期待される。