Grant-in-Aid for Scientific Research (A)
Materials/Mechanics of materials
|Research Institution||Tohoku University|
ABE Hiroyuki Tohoku University, President, 総長 (00005266)
TAKAGI Toshiyuki Institute of Fluid Science, Tohoku University, Professor, 流体科学研究所, 教授 (20197065)
SHIRATORI Masaki Faculty of Engineering, Yokohama National University, Professor, 工学部, 教授 (60017986)
SAKA Masumi Graduate School of Engineering, Tohoku University, Professor, 大学院・工学研究科, 教授 (20158918)
OHTANI Ryuichi Graduate School of Engineering, Kyoto University, Professor, 大学院工学研究科, 教授 (50025946)
AOKI Shigeru Graduate School of Information Science and Engineerng, Tokyo Institute of Techno, 大学院情報理工学研究科, 教授 (90016436)
|Project Fiscal Year
1996 – 1998
Completed(Fiscal Year 1998)
|Budget Amount *help
¥13,400,000 (Direct Cost : ¥13,400,000)
Fiscal Year 1998 : ¥4,000,000 (Direct Cost : ¥4,000,000)
Fiscal Year 1997 : ¥4,000,000 (Direct Cost : ¥4,000,000)
Fiscal Year 1996 : ¥5,400,000 (Direct Cost : ¥5,400,000)
|Keywords||Resistivity / Permeability / Magnetoacoustic Emission / Eddy Current / Mechanics of Materials / Strain / Stress / Degradation / 抵抗率 / 透磁率 / 磁気AE / 渦電流 / 材料力学 / ひずみ / 応力 / 劣化|
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
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