Performance of Different Sensors for Monitoring of the Vibration Generated during Thermosonic Non-destructive Testing

  • Kang, Bu-Byoung (Super-Speed Train Research Department, Korea Railroad Research Institute)
  • 투고 : 2011.02.25
  • 심사 : 2011.04.07
  • 발행 : 2011.04.30

초록

Vibration monitoring is required for reliable thermosonic testing to decide whether sufficient vibration is achieved in each test for the detection of cracks. From a practical point of view, a cheaper and convenient monitoring method is better for the application to real tests. Therefore, the performance of different sensors for vibration monitoring was investigated and compared in this study to find a convenient and acceptable measurement method for thermosonics. Velocity measured by a laser vibrometer and strain provide an equivalent HI when measured at the same position. The microphone can provide a cheaper vibration monitoring device than the laser and the heating index calculated by a microphone signal shows similar characteristics to that calculated from velocity measured by the laser vibrometer. The microphone frequency response shows that it underestimates high frequency components but it is applicable to practical tests because it gives a conservative value of HI.

키워드

참고문헌

  1. M. Imregun and K. Y. Sanliturk, "Natural frequency and damping changes produced by fatigue cracks," in Proceedings of the 15 th Seminar on Modal Analysis, Leuven, Belgium, pp. 791-805 (1990)
  2. C. F. Beards, "Structural vibration: analysis and damping," Arnold, London, (1996)
  3. A. P. Bovsunovsky and C. Surace, "Considerations regarding superharmonic vibrations of a cracked beam and the variation in damping caused by the presence of the crack," Journal of Sound and Vibration, 288(4-5), pp. 865-886 (2005) https://doi.org/10.1016/j.jsv.2005.01.038
  4. M. Morbidini, "A comparison of the vibration-modulation and thermosonic ndt techniques," Ph. D. thesis, Imperial College, University of London (2007)
  5. M. Morbidini, P. Cawley, T. Barden and D. Almond, "Prediction of the thermosonic signal from fatigue cracks in metals using vibration damping measurements," Journal of Applied Physics, 100(10), pp. 1-13 (2006)
  6. C. J. Pye and R. D. Adams, "Heat emission from damaged composite materials and its use in nondestructive testing," Journal of Physics D-Applied Physics, 14(5), pp. 927-941 (1981) https://doi.org/10.1088/0022-3727/14/5/026
  7. P. Duour, M. Morbidini and P. Cawley, "Comparison between a type of vibro-acoustic modulation and damping measurement as NDT techniques," NDT&E International 39, pp. 123-131 (2006) https://doi.org/10.1016/j.ndteint.2005.07.010
  8. P. Duour, M. Morbidini and P. Cawley, "A study of the vibro-acoustic modulation technique for the detection of cracks in metals," Journal of the Acoustical Society of America, 119(3), pp. 1463-1975 (2006) https://doi.org/10.1121/1.2161429
  9. D. D. Ho, D. S. Hong and J. T. Kim, "Nondestructive evaluation of railway bridge by system identification using field vibration measurement," Journal of the Korean Society for Nondestructive Testing, Vol. 30, No. 6, pp. 527-538 (2010)
  10. H. Jeong and D. Barnard, "Measurement of sub-and super harmonic waves at the interfaces of fatigue-cracked CT specimen," Journal of the Korean Society for Nondestructive Testing, Vol. 31, No. 1, pp. 527-538 (2011)
  11. X. Y. Han, Z. Zeng, W. Li, M. S. Islam, J. P. Lu, V. Loggins, E. Yitamben, L. D. Favro, G. Newaz and R. L. Thomas, "Acoustic chaos for enhanced detectability of cracks by sonic infrared imaging," Journal of Applied Physics, 95(7), pp. 3792-3797 (2004). https://doi.org/10.1063/1.1652243
  12. M. Rothenfusser and C. Homma, "Acoustic thermography: vibrational modes of cracks and the mechanism of heat generation," in Review of Progress in Quantitative Nondestructive Evaluation 24, Vol. 760 of AIP Conference Proceedings, Edited by D. O. Thompson and D. E. Chimenti, American Institute of Physics, Melville, NY, pp. 624-631 (2004)
  13. X. Y. Han, "Frequency dependence of the thermosonic effect," Review of Scientic Instruments, 74(1), pp. 414-416 (2003) https://doi.org/10.1063/1.1518550
  14. Technical Report, B&K, DK-2850 Nrum, Denmark