Study on Electromagnetic Fracture Mechanics of Material Systems for New Electromagnetic Devices

新型电磁器件材料体系电磁断裂力学研究

• 批准号: 08455049
• 负责人: SHINDO Yasuhide
• 金额: $ 5.06万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455049/
• 关键词: Elasticity; Electromagnetic Fracture Mechanics; Integral Transforms; Finite Element Analysis; Material Testing; Electromagnetic Material; Electromagneto-Elastic Interaction; Fracture Toughness; 導電性・磁性材料; 圧電セラミックス; 破壊靱性; 強電磁場; 超伝導応用機器; 電子・電気機械

Design and development of new electromagnetic devices require basic research on electromagnetic fracture mechanics. In this research project, the electromagnetic fracture mechanics of material systems is investigated. From the theoretical considerations and experimental results for electromagnetic material systems, the following can be concluded1) (a) We consider the scattering of time harmonic flexural waves by a through crack in a conducting plate under a uniform magnetic field normal to the crack surface for two special cases, perfect conductivity and quasistatic electromagnetic field, which are of physical interest. The dynamic moment intensity factor versus frequency is computed and the influence of the magnetic field and the angle of incidence on the normalized values is displayed graphically.(b) We discuss the magneto-elastic interactions and singular moments in a soft ferromagnetic plate with a through crack under a uniform magnetic field normal to the plate surface. The static … More and dynamic moment intensity factors are computed and the influence of the magnetic field on the normalized values is displayed graphically.2) We examine the bending of a soft ferromagnetic beam plate in a transverse magnetic field both theoretically and experimentally. The effect of magnetic field on the deflection and strain is shown graphically. A comparison of the deflection and strain is made between theory and experiment, and the agreement is good for the magnetic field considered. We also study the effect of magnetic field on the fracture behavior of a soft ferromagnetic beam plate.3) We consider the cryogenic fracture behavior of structural alloys and weldments for superconductiong fusion magnets in high magnetic fields both analytically and experimentally.4) (a) We consider the static and dynamic problems of cracked piezoelectric materials and composites. Numerical calculations are carried out, and the stress intensity factor, energy release rate and crack growth rate are obtained. We also study the static behavior of the elastic and electric variables in the vicinity of a surface electrode attached to a piezoelectric ceramic.(b) We discuss the scattering of normally incident longitudinal waves by a finite crack in an infinite isotropic dielectric body under a uniform electric field. The dynamic stress intensity factor versus frequency is computed and the influence of the electric field on the normalized values is displayed graphically.5) (a) We perform the bending tests on piezoelectric material systems and examine the piezoelectric effects on the deflection. We also employ the finite element analysis to study the electromechanical behavior of piezoelectric material systems. Numerical results are compared with the experimentally measured response.(b) We carry out the Vickers indentation tests on piezoelectric materials and examine the influence of applied electric field, polarization and load on the fracture toughness. The specimen fracture behavior is also simulated numerically using the finite element technique. Numerical results are provided to illustrate both qualitative and quantitative behavior of the induced electromechanical fields.6) We performe the numerical simulation for analyzing the electromagnetic fracture and deformation of material systems. The predictions obtained from the simulation correlate very well with the experiments. Less

新电子设备的设计和开发需要有关电子断裂力学的基础研究。在该研究项目中，研究了材料系统的电子断裂力学。从电子材料系统的理论考虑和实验结果来看，可以得出以下1）（a）我们考虑在两个特殊情况下，在均匀的磁场下，在均匀的磁场下，在均匀的磁场下，通过裂纹在两个特殊情况下，在均匀的磁场下通过裂纹散射，完美的电导率，完美的电导率和准静态电磁场，具有物理利益。计算动态力矩强度因子与频率的动态强度因子，并以图形方式显示磁场和入射角对归一化值的影响。（b）我们讨论了磁弹性相互作用和柔软的铁磁板中的奇异矩，并在与板表面正常的均匀磁场下通过裂纹在裂纹的情况下通过a裂开。计算静态……更多的动态力矩强度因子，并以图形方式显示磁场对归一化值的影响。2）我们检查了理论和实验性的横向磁场中软铁磁束板的弯曲。磁场对挠度和应变的影响以图形方式显示。挠度和应变的比较是在理论和实验之间进行的，并且一致性对考虑的磁场有益。我们还研究了磁场对软铁磁束板的裂缝行为的影响。3）我们考虑了高磁场中的结构合金和焊接的低温裂缝行为和焊接的高磁融合磁体的焊接。进行数值计算，并获得应力强度因子，能量释放速率和裂纹生长速率。我们还研究了连接到压电陶瓷的表面电气附近弹性和电变量的静态行为。计算动态应力强度因子与频率，并以图形方式显示电场对归一化值的影响。我们还采用有限元分析来研究压电材料系统的机电行为。将数值结果与实验测量的响应进行了比较。（b）我们对压电材料进行了维克斯压痕测试，并检查了施加的电场，极化和负载对断裂韧性的影响。还使用有限元技术基本上模拟了样品骨折行为。提供了数值结果来说明诱导的机电场的定性和定量行为。6）我们执行了数值模拟，用于分析材料系统的电磁断裂和变形。从模拟获得的预测与实验非常相关。较少的

项目成果

Y.Shindo: "Singular Stress and Electric Fields of a Piezoelectric Ceramic Strip with a Finite Crack under Longitudinal Shear" Acta Mechanica. 120-1/4. 31-45 (1997)

Y.Shindo：“纵向剪切下具有有限裂纹的压电陶瓷条的奇异应力和电场”《力学学报》。

Y.Shindo: "Scattering of Oblique Flexural Waves by a Through Crack in a Conducting Mindine Plate in a Uniform Magnetic Field" International Journal of Solids and Structures. (in press).

Y.Shindo：“均匀磁场中传导 Mindine 板中的贯通裂纹引起的斜弯曲波的散射”《国际固体与结构杂志》。

Y.Shindo: "The Scattering of Oblique Flexural Waves of a Cracked Conducting Plate in a Uniform Magnetic Field" Acta Mechanica. 128-1/2. 15-27 (1998)

Y.Shindo：“均匀磁场中裂纹导电板的斜弯曲波的散射”《力学学报》。

Y.Shindo: "Impact Response of a Finite Crack in an Orthotropic Piezoelectric Ceramic" Acta Mechanica. (in press).

Y.Shindo：“正交各向异性压电陶瓷中有限裂纹的冲击响应”《力学学报》。

堀口 勝三: "磁場内におけるフェライト系ステンレス鋼平板の曲げ試験と磁気弾性解析" 日本機械学会論文集,A編. (印刷中).

Katsuzo Horiguchi：“磁场中铁素体不锈钢平板的弯曲试验和磁致弹性分析”日本机械工程师学会会议录，A 卷（印刷中）。