Improvement in performance of titanium alloy produced by 3D printer using advanced rapid high-temperature heat treatment

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02027
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: Morita Tatsuro 京都工芸繊維大学, 機械工学系, 教授 (90239658)
• Co-Investigator(Kenkyū-buntansha): 武末 翔吾 京都工芸繊維大学, 機械工学系, 助教 (00846058) ; 小茂鳥 潤 慶應義塾大学, 理工学部(矢上), 教授 (30225586)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 三次元プリンタ / LPBF / チタン合金 / 高周波誘導加熱 / 高速酸窒化 / 疲労強度 / 摩擦摩耗特性

Outline of Final Research Achievements

In this study, the fatigue strength of titanium alloy produced by a 3D printer was remarkably improved in short time (60 s) by a newly developed advanced rapid high-temperature heat treatment (improvement rate: 550 %). The fatigue strength of the alloy was fruther improved to the same level as that of the wrought material by combining the heat treatment with fine-particle bombarding. Rapid oxynitridation caused by the above heat treatment in air resulted in the formation of a hardened layer (thickness: 100 μm). As a result, the friction coefficient was significantly reduced to 0.17 and the wear resistance was markedly improved.

Free Research Field

材料力学および機械材料関連

Academic Significance and Societal Importance of the Research Achievements

本研究で得られた成果は，直接的には三次元プリンタ製チタン合金から造形される医療用インプラントや各種製品の高性能化を達成するために活用可能である．特に疲労強度の改善効果は，この材料の主たる問題点を後処理により解決可能であることを意味しており，応用範囲は広い．また，本研究で得られた摩擦摩耗特性の改善に関わる知見は，ステンレス鋼やアルミ合金等にも応用可能と考えられ，さらなる活用が期待される．