Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

The Korean Society for Nondestructive Testing (한국비파괴검사학회)
권호 표지
DOI QR코드

DOI QR Code

Initial Second Harmonic Generation in Narrowband Surface Waves by Multi-Line Laser Beams for Two Kinds of Spatial Energy Profile Models: Gaussian and Square-Like

  • Received : 2013.05.28
  • Accepted : 2013.06.21
  • Published : 2013.06.30
Download PDF
⟨ Previous Next ⟩

Abstract

Acoustic nonlinearity of surface waves is an effective method to evaluate the micro damage on the surface of materials. In this method, the $A_1$ (magnitude of the fundamental wave) and $A_2$ (magnitude of the second-order harmonic wave) are measured for evaluation of acoustic nonlinearity. However, if there is another source of second-order harmonic wave other than the material itself, the linear relationship between $A_1{^2}$ and $A_2$ will not be guaranteed. Therefore, the second-order harmonic generation by another source should be fully suppressed. In this paper, we investigated the initial second-order harmonic generation in narrowband surface waves by multi-line laser beams. The spatial profile of laser beam was considered in the cases of Gaussian and square-like. The temporal profile was assumed to be Gaussian. In case of Gaussian spatial profile, the generation of the initial second-order harmonic wave was inevitable. However, when the spatial profile was square-like, the generation of the initial second-order harmonic wave was able to be fully suppressed at specific duty ratio. These results mean that the multi-line laser beams of square-like profile with a proper duty ratio are useful to evaluate the acoustic nonlinearity of the generated surface waves.

Keywords

References

  1. K. Y. Jhang, J. I. Lee and T. H. Lee, "Acoustic nonlinearity of surface wave in a fatigue aluminum alloy specimen," Materials Transactions, Vol. 53, No. 2, pp. 303-307 (2012) https://doi.org/10.2320/matertrans.I-M2011846
  2. S. V. Walker, K. Y. Kim, J. Qu and L. J. Jacobs, "Fatigue damage evaluation in A36 steel using nonlinear Rayleigh surface waves," NDT&E International, Vol. 48, pp. 10-15 (2012) https://doi.org/10.1016/j.ndteint.2012.02.002
  3. M. Liu, J. Y. Kim, L. Jacobs and J. Qu, "Experimental study of nonlinear Rayleigh wave propagation in shot-peened aluminum plates - Feasibility of measuring residual stress," NDT&E International, Vol. 44, pp. 67-74 (2011) https://doi.org/10.1016/j.ndteint.2010.09.008
  4. T. H. Nam, S. H. Choi, T. H. Lee, K. Y. Jhang and C. S. Kim, "Acoustic nonlinearity of narrowband laser-generated surface waves in the bending fatigue of Al6061 alloy," Journal of the Korean Physics Society, Vol. 57, No. 5, pp. 1212-1217 (2010) https://doi.org/10.3938/jkps.57.1212
  5. C. B. Scruby and L. E. Drain, "Laser Ultrasonics: Techniques and Applications," Bristol: Adam Hilger (1990)
  6. A. D. W. McKie, J. W. Wagner, J. B. Spicer and C. M. Penny, "Laser generation of narrow-band and directed ultrasound," Ultrasonics, Vol. 27, pp. 323-330 (1989) https://doi.org/10.1016/0041-624X(89)90030-9
  7. J. Huang, S. Krishnaswamy and J. D. Achenbach, "Laser generation of narrow-band surface waves," Journal of the Acoustical Society of America, Vol. 92, No. 5, pp. 2527-2531 (1992) https://doi.org/10.1121/1.404422
  8. T. W. Murray, J. B. Deaton Jr. and J. W. Wagner, "Experimental evaluation of enhanced generation of ultrasonic waves using an array of laser sources," Ultrasonics, Vol. 34, pp. 69-77 (1996) https://doi.org/10.1016/0041-624X(95)00090-P
  9. H. Nishino, Y. Tsukahara, Y. Nagata, T. Koda and K. Yamanaka, "Excitation of high frequency surface acoustic waves by phase velocity scanning of a laser interference fringe," Applied Physics Letters, Vol. 62, No. 17, pp. 2036-2038 (1993) https://doi.org/10.1063/1.109471
  10. H. Nakano and S. Nagai, "Laser generation of antisymmetric lamb waves in thin plates," Ultrasonics, Vol. 29, No. 3, pp. 230-234 (1991) https://doi.org/10.1016/0041-624X(91)90061-C
  11. D. Royer and E. Dieulesaint, "Analysis of thermal generation of Rayleigh waves," Journal of Applied Physics, Vol. 56, No. 9, pp. 2507-2511 (1984) https://doi.org/10.1063/1.334314
  12. E. A. Ash, E. Dieulesaint and H. Rakouth, "Generation of surface acoustic waves by means of a C. W. laser," Electronics Letters, Vol. 16, No. 12, pp. 470-472 (1980) https://doi.org/10.1049/el:19800331
  13. H. G. Seo, M. H. Kim, S. H. Choi, C. S. Kim and K. Y. Jhang, "Frequency characteristics of surface wave generated by single-line pulsed laser beam with two kinds of spatial energy profile models: Gaussian and square-like," Journal of the Korean Society for Nondestructive Testing, Vol. 32, No. 4, pp. 347-354 (2012) https://doi.org/10.7779/JKSNT.2012.32.4.347
  14. Y. H. Berthelot and J. Jarzynski, "Directional laser generation and detection of ultrasound with arrays of optical fibers," Journal of Nondestructive Evaluation, Vol. 9, No. 4, pp. 271-277 (1990) https://doi.org/10.1007/BF00565645
  15. I. Arias and J. D. Achenbach, "Thermoelastic generation of ultrasound by linefocused laser irradiation," International Journal of Solids and Structures, Vol. 40, No. 25, pp. 6917-6935 (2003) https://doi.org/10.1016/S0020-7683(03)00345-7
  16. J. Zimmerman, W. Wlosinski and Z. R. Lindemann, "Thermo-mechanical and diffusion modeling in the process of ceramicmetal friction welding," Journal of Materials Processing Technology, Vol. 209, pp. 1644-1653 (2009) https://doi.org/10.1016/j.jmatprotec.2008.04.012
  17. Y. Chao and X. Qi, "Thermal and thermo-mechanical modelling of friction stir welding of aluminium alloy 6061-T6," Journal of Materials Processing Technology, Vol. 7, No. 10, pp. 215-233 (1998)
  18. H. Sun, S. Zhang and B Xu, "Influence of viscoelastic property on laser-generated surface acoustic waves in coating-substrate systems," Journal of Applied Physics, Vol. 109, pp. 073107 (2011) https://doi.org/10.1063/1.3553447