Development of highly efficient machining technology for niobium-titanium alloys with low elastic modulus similar to bone

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K04200
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18020:Manufacturing and production engineering-related
• Research Institution: Kanazawa Institute of Technology
• Principal Investigator: Kato Hideharu 金沢工業大学, 工学部, 教授 (90278101)
• Co-Investigator(Kenkyū-buntansha): 森本 喜隆 金沢工業大学, 工学部, 教授 (00290734)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 駆動型ロータリー工具 / ニオブチタン合金 / ヘール加工 / 高能率加工 / 切削機構 / チタニウム合金

Outline of Final Research Achievements

Niobium-titanium (Nb-Ti) alloy materials are composed of two elements, Nb and Ti, with low cytotoxicity. It is also expected to be used as an implant material because it has an elastic modulus close to that of human bone and is easy to supply primary molded products by precision casting methods. However, due to its high cohesion characteristics and low thermal conductivity, it has a short tool life and extremely high machinability, making it difficult to perform highly efficient machining. In this study, a rotary tool with a round insert or cylindrical end face periphery was driven and used in combination with hail cutting to enable highly efficient machining. In addition, a longer tool life is achieved in an environment with an oil mist supply. Furthermore, the cutting mechanism of this method is investigated and its usefulness is clarified.

Free Research Field

生産加工・加工学

Academic Significance and Societal Importance of the Research Achievements

Nb-Ti合金材料の高能率加工技術の開発においては，微細加工技術の開発においては、(a) 最適工具材料の選定と形状成形，(b) 極薄厚さの切りくずを生成する加工条件の把握と切削機構の解明が需要なポイントである．本研究ではシリンダ形状の円筒端面外周部を切れ刃とするロータリ工具を用いて切取り厚さを薄く制御することとヘール加工を組み合わせた加工法を提案し，切削温度を低減した高能率加工が可能であることを明らかとしている．これにより，生体適合性に優れ低い弾性率を有するNb-Ti合金の人工骨への適用への可能性を高められた．