Progress in Superconductivity and Cryogenics (한국초전도ㆍ저온공학회논문지)

The Korean Society of Superconductivity and Cryogenics (한국초전도저온학회)
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Study on Improvement of the Piezoelectric Properties of Acoustic Emission Sensor to be Used for Superconducting Application Systems

초전도 응용기기 안정성 진단을 위한 AE센서용 압전소자의 성능개선 연구

  • 김경준 (고려대학교 신소재공학과 초전도연구실 그룹) ;
  • 김주형 (고려대학교 신소재공학과 초전도연구실 그룹) ;
  • 송정빈 (고려대학교 신소재공학과 초전도연구실 그룹) ;
  • 백종후 (한국세라믹기술연구원) ;
  • 장재영 (연세대학교 전기공학과 초전도응용 연구실) ;
  • 고태국 (연세대학교 전기공학과) ;
  • 이해근 (고려대학교 신소재공학과)
  • Received : 2010.09.01
  • Accepted : 2010.09.13
  • Published : 2010.09.30
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Abstract

Acoustic emission (AE) signal from an HTS tape has a low signal to noise ratio, due to the large amount of noise caused by the boiling of the liquid cryogen or mechanical vibration from the cryo-cooler. In an attempt to improve the sensitivity of the AE sensor, $Pb(Zr_{0.54}Ti_{0.46})O_3$ + 0.2 wt% $Cr_2O_3$ + 1.0 wt.% $Nb_2O_5$ ceramics sintered at $1200^{\circ}C$ was synthesized. In addition, the resonance ($f_r$) and anti-resonance frequencies ($f_a$) were measured using the specimens with various thicknesses (1.0, 1.5, 2.0, 2.5 and 3.0 mm). According to the test results, large AE signals with high frequencies were obtained from the AE sensor fabricated using a piezoelectric disc with a thinner thickness.

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References

  1. H. G. Lee, H. M. Kim, J. Jankowski and Y. Iwasa, "Detection of 'hot spots' in HTS coils and test samples with acoustic emission signals", IEEE Transactions on Applied Superconductivity, Vol. 14, Issue 2, pp. 1298-1301, June, 2004. https://doi.org/10.1109/TASC.2004.830559
  2. H. M. Kim, K. B. Park, B. W. Lee, I. S. Oh, J. W. Sim, O. B. Hyun, Y. Iwasa and H. G. Lee, "A stability verification technique using acoustic emission for an HTS monofilar component for a superconducting fault current limiter", Superconductor Science and Technology, Vol. 20, Issue 6, pp. 506-510, 2007. https://doi.org/10.1088/0953-2048/20/6/004
  3. H. Nomura, K. Takahisa, K. Koyama and T. Sakai, "Acoustic emission from superconducting magnets", Cryogens, Vol. 17, Issue 8, pp. 471-481, 1977. https://doi.org/10.1016/0011-2275(77)90024-8
  4. C. Schmidt, G. Pasztor, "Acoustic emission from NbTi superconductors during flux jump", Cryogenics, Vol. 19, Issue 10, pp. 608-610, 1979. https://doi.org/10.1016/0011-2275(79)90034-1
  5. H. G. Lee, J. Bascunan and Y. Iwasa, "A High -Temperature Superconducting Double -Pancake Insert for an NMR Magnet", IEEE Transactions on Applied Superconductivity, Vol. 13, Issue 2, pp. 1546-1549, June. 2003. https://doi.org/10.1109/TASC.2003.812770
  6. H. M. Kim, K. B. Park, B. W. Lee, I. S. Oh, J . W. Sim., O. B. Hyun, Y. Iwasa and H. G. Lee, "A stability verification technique using acoustic emission for an HTS monofilar component for a superconducting fault current limiter", Superconducting Science and Technology, Vol. 20, Issue 6, pp. 506, 2007. https://doi.org/10.1088/0953-2048/20/6/004
  7. I. Grinberg, V. R. Cooper, and A. M. Rappe, "Relationship between local structure and phase transitions of a disordered solid solution", Nature Vol. 419, pp. 909-911, 2002. https://doi.org/10.1038/nature01115
  8. J. H. Kim, J. B. Song, Y. H. Jeong, Y. J. Lee, J. H. Paik, W. S. Kim and H. G. Lee, "Fabrication of a High Performance Acoustic Emission (AE) Sensor to Monitor and Diagnose Disturbances in HTS Tapes and Magnet ", Metals and Materials International, Vol. 16, pp. 109-113, 2010. https://doi.org/10.1007/s12540-010-0109-5