Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Application of a NDI Method Using Magneto-Optical Film for Micro-Cracks

  • Jaekyoo Lim (Department of Mechanical Design, Research Center of Industrial Technology, Chonbuk National University) ;
  • Lee, Hyoungno (G. S., Department of Mechanical Design, Chonbuk National University) ;
  • Lee, Jinyi (R&D Center, Lacomm Co., Ltd.) ;
  • Tetsuo Shoji (Fracture Research Institute, Faculty of Eng., Tohoku University)
  • Published : 2002.05.01
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Abstract

Leakage magnetic flux is occurred in the cracked area of magnetized specimens, and also it changes the magnetic domain area of the magneto-optical film positioned on the specimen. It causes the change of the optical permeability of the magnetic domain on the crack area. So crack images can be obtained easily using this principle. On the other hand, utilizing a laser in this method makes possible to perform a remote sensing by detecting the light intensity contrast between cracked area and normal area. This paper shows the application of non-destructive inspection system taking advantage of magneto-optical method for micro-cracks and presents examples applied to the several types of specimens having fatigue cracks and fabricated cracks using this method. Also the authors prove the possibility of this method as a remote sensing system under the oscillation load considering application to real fields.

Keywords

References

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