Evaluation of the electromagneto-mechanical characteristics of the magnetostrictive bolt and development of the devices using magnetostrictive bolt

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K13654
• 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: Ibaraki University
• Principal Investigator: Mori Kotaro 茨城大学, 理工学研究科(工学野), 講師 (40712740)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 磁歪材料 / 電磁力学特性 / センシング / 材料力学

Outline of Final Research Achievements

The purpose of this study is to develop a bolt using magnetostrictive materials that has a self-sensing capability for the force and a retightening capability by external magnetic field, and to consider the electromagneto-mechanical characteristics of FeCo bolts theoretically and experimentally. And, we also studied the energy harvesting characteristics due to vibration and shock, and the design and structure of multifunctional bolt-type devices.

Free Research Field

材料システム設計学

Academic Significance and Societal Importance of the Research Achievements

ネジは多くの機械，構造物で固定のために用いられているが，時間と共に緩み，締結力が低下することが問題となっている．また，ネジは弛みだけでなく過度な締付けも，破壊の原因となるため，ネジ内部の軸力の把握が重要である．これらの問題に対し，磁歪材料製ネジは，非接触かつ大掛かりな装置を用いずともネジ内部の軸力を把握することが可能となった．また，鉄コバルト合金は安価で通常のネジと近い機械的特性を持っているため，既存のネジと置換できる点も優れている．