Research on Highly Sensitive Measurement and Evaluation of Electromagnetic Properties and Quantities in Relation to Strain and Stress, and Materials Degradation

1. 推导了磁场作用下可变形材料的本构方程。从理论上证明了磁弹性相互作用。为了提高无损检测技术的水平，发展了电磁场的数值分析方法，分析了电机中的磁通量和涡流，以及层状材料的轴对称电磁场。在低磁场条件下，测量了不同应力值下的磁通密度分布。传感器定位的合适区域与对应力变化的高灵敏度有关。改进了通过检测应力引起的磁各向异性来测量残余应力的方法。开发了用于材料降解和微织构评价的高灵敏度传感器和信号处理技术。此外，还开发了紧密耦合探针电位跌落技术，对裂纹进行高灵敏度无损检测。详细研究了磁致伸缩效应，并将其应用于应力测量。研究了利用磁箔和磁膜测量非磁性材料表面应力的方法。提出了钢丝和钢丝绳应力和退化的磁性无损检测方法。讨论了材料的显微组织与磁性能的关系。提出了利用巴克豪森噪声、磁机械声发射和电磁声换能器对降解材料进行无损评价的方法。磁性分级材料也能被制造出来。针对以多裂纹为代表的材料损伤，提出了用直流电势降、交变磁化强度和直流电流产生的磁场评价材料损伤的方法。提出了利用微波对介质材料缺陷进行高灵敏度检测的无损检测方法；提出了利用磁光元件对介质材料表面小裂纹进行无损检测的方法。少

1. The constitutive equations were derived for deformable materials under magnetic field. The magnetoelastic interactions were shown theoretically.2. The numerical analysis methods of electromagnetic field were developed for the advancement of nondestructive testing technique, analyzing magnetic flux and eddy current in electrical machines, and an axisymmetrical electromagnetic field of layered materials.3. The distribution of magnetic flux density was measured for various values of stress under low magnetic field. The suitable area in sensor positioning was determined in connection with higher sensitivity to the change in stress. The measuring method of residual stress by detecting the magnetic anisotropy induced by stress was improved.4. The high sensitivity sensor and the signal processing for the evaluation of materials degradation and microtexture were developed. Also the closely coupled probes potential drop technique was developed for highly sensitive nondestructive evaluation o … More f a crack.5. The magnetostriction effect was examined in detail and applied to stress measurement.6. The technique to measure the stress on the surface of non-magnetic material using magnetic foil and film was developed.7. The magnetic nondestructive methods for evaluating the stress and degradation of steel wires and wire ropes were developed.8. The relationship between the microtexture of material and the magnetic properties was discussed. The nondestructive evaluation methods of degraded materials by using the Barkhausen noise, magnetomechanical acoustic emission and electromagnetic acoustic transducers were developed. A magnetically graded material was also able to be manufactured.9. For the material damage represented by multiple cracks, the evaluation methods by d.c. potential drop, alternating magnetization and the magnetic field produced by d.c. current were developed.10. The nondestructive evaluation method utilizing microwave was developed for highly sensitive detection of the defects in dielectric materials, And the nondestructive detection method for small surface crack using magneto-optical element was developed. Less