Development of estimation method for temperature and strain rate dependencies via ball impact test

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K14846
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: Tokyo University of Science
• Principal Investigator: Ito Kiyohiro 東京理科大学, 工学部機械工学科, 助教 (10778210)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: ひずみ速度依存性 / 温度依存性 / 球体衝突 / 金属材料 / 圧痕

Outline of Final Research Achievements

The deformation resistance of metallic materials varies depending on the temperature and strain rate. In order to realize simple and high-accuracy estimation of the temperature and strain rate dependencies, an original estimation method based on the ball impact test was developed. Using this method, the temperature and strain rate dependencies can be estimated with high-accuracy from the difference between indentation sizes formed by the ball impact test at different temperatures or different impact velocities. The ball impact analysis based on the finite element method demonstrated that the temperature and strain rate dependencies can be estimated with high-accuracy under the conditions of various materials, ball radii, and impact velocities by the developed method.

Free Research Field

材料力学・機械材料学

Academic Significance and Societal Importance of the Research Achievements

本研究で新たに開発した評価手法では，異なる温度もしくは衝突速度で球体衝突試験を行い，材料表面に形成した圧痕寸法を測定するだけで温度やひずみ速度依存性を高精度に評価することができる．さらに，既存の評価手法では困難であった100000 1/s以上の超高ひずみ速度を実現できる．これにより，自動車などの輸送機器の衝突安全性向上や，切削やプレスといった機械加工の高速・高効率化など，幅広い産業分野への貢献が期待できる．また，超高ひずみ速度下における材料の変形メカニズムの解明にも有効となり得ることが期待でき，高い学術的意義も有している．