Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

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

DOI QR Code

Assessment of Plastic Deformation in Al6061 Alloy using Acoustic Nonlinearity of Laser-Generated Surface Wave

레이저 여기 표면파의 음향비선형성을 이용한 Al6061 합금의 소성변형 평가

  • 김정석 (한양대학교 자동차공학과) ;
  • 남태형 (한양대학교 자동차공학과) ;
  • 최성호 (한양대학교 자동차공학과) ;
  • 장경영 (한양대학교 기계공학부)
  • Received : 2011.01.02
  • Accepted : 2012.02.10
  • Published : 2012.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

The objective of this study is to assess plastic deformation in aluminium alloy by acoustic nonlinearity of laser-generated surface waves. A line-arrayed laser beam made by high-power pulsed laser and mask slits is utilized to generate the narrowband surface wave and the frequency characteristics of laser-generated surface waves are controlled by varying the slit opening width and slit interval of mask slits. Various degrees of tensile deformation were induced by interrupting the tensile tests so as to obtain aluminum specimens with different degrees of plastic deformation. The experimental results show that the acoustic nonlinear parameter of a laser-generated surface wave increased with the level of tensile deformation and it has a good correlation with the results of micro-Vickers hardness test and electron backscatter diffraction (EBSD) test. Consequently, acoustic nonlinearity of laser-generated surface wave could be potential to characterize plastic deformation of aluminum alloy.

본 연구의 목적은 비접촉식 레이저 여기 표면파의 비선형성 계측을 통하여 소성 변형된 알루미늄 합금의 소성변형을 평가하고자 하는 데 있다. 슬릿마스크와 고출력 펄스 레이저를 통한 선배열 레이저빔을 이용하여 협대역의 표면파를 발생 시켰으며, 표면파의 음향 비선형 특성을 이용하기 위하여 슬릿 마스크의 열림 폭과 간격을 변화시킴으로써 레이저 여기 표면파의 주파수 특성을 제어하였다. 스트로크 제어를 통한 인장시험을 통하여 단계별 인장 소성변형 정도를 달리하는 시험편을 제작하였다. 실험결과 인장 소성 변형율이 커짐에 따라 음향 비선형 파라미터는 증가하였으며, 경도 및 EBSD 측정결과 손상의 정도와 매우 밀접한 관계를 보였다. 결과적으로 본 연구에서의 레이저 여기 표면파의 비선형 평가기법은 알루미늄 합금의 소성변형 평가에 매우 유용할 것으로 판단된다.

Keywords

References

  1. V. V. S. Jaya Rao, E. Kannan, R. V. Prakash, and K. Balasubramaniam, "Fatigue damage characterization using surface acoustic wave nonlinearity in aluminum alloy AA7175-T7351," Journal of Applied Physics, Vol. 104, pp. 123508 (2008) https://doi.org/10.1063/1.2956396
  2. C. S. Kim, I. K. Park, K. Y. Jhang and C. Y. Hyun, "Long-term aging diagnosis of rotor steel using acoustic nonlinearity," Journal of the Korean Society for Nondestructive Testing, Vol. 31, No. 6, pp. 642-629 (2011)
  3. 백승현, 이태훈, 김정석, 장경영, "열처리된 SA508 합금에서의 초음파 비선형성 측정: 결 정립과 석출물 영향", 비파괴검사학회지, Vol. 30, No. 5, pp. 451-457 (2010)
  4. J. H. Cantrell, "Dependence of microelasticplastic nonlinearity of martensitic stainless steel on fatigue damage accumulation," Journal of Applied Physics, Vol. 100, pp. 063508 (2006) https://doi.org/10.1063/1.2345614
  5. J. H. Cantrell and X. G. Zhang, "Nonlinear Acoustic Response from Precipitate-Matrix Misfit in a Dislocation Network," Journal of Applied Physics, Vol. 84, pp. 15-18 (1998)
  6. J. H. Cantrell and W. T. Yost, "Nonlinear ultrasonic characterization of fatigue microstructures," International Journal of Fatigue, Vol. 23, pp. 487-490 (2001) https://doi.org/10.1016/S0142-1123(01)00162-1
  7. J. L. Blackshire, S. Sathish, J. Na and J. Frouin, "Nonlinear Laser Ultrasonic Measurements of Localized Fatigue Damage," Review of Progress in Quantitative Nondestructive Evaluation, Vol. 22, pp. 1479-1488 (2003)
  8. C. B. Scruby and L. E. Drain, "Laser Ultrasonics: Techniques and Applications", Adam Hilger, Bristol, (1990)
  9. 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
  10. A. Harata, N. Nishimura and T. Sawada, "Laser-induced surface acoustic-waves and photothermal surface gratings generated by crossing 2 pulsed laser-beams," Applied Physics Letters, Vol. 57, pp. 132-134 (1990) https://doi.org/10.1063/1.103964
  11. D. Royer and E. Dieulesaint, "Analysis of thermal generation of Rayleigh waves," Journal of Applied Physics, Vol. 56, pp. 2507-2511 (1984) https://doi.org/10.1063/1.334314
  12. T. H. Nam, S. H. Choi, T. H. Lee and K. Y. Jhang, C. S. Kim, "Acoustic Nonlinearity of Narrowband Laser-generated Surface waves in the Bending Fatigue of Al6061 Alloy," Journal of the Korean Physical Society, Vol. 57, pp. 1212-1217 (2010) https://doi.org/10.3938/jkps.57.1212
  13. Y. Shui, Y. Solodov, "Nonlinear Properties of Rayleigh and Stoneley Waves in Solids," Journal of Applied Physics, Vol. 64, pp. 6155-6165 (1988) https://doi.org/10.1063/1.342120
  14. C. E. Duffer and C. P. Burger, "Narrow Band Laser Ultrasonic NDE," Review of Progress in Quantitative nondestructive Evaluation, Vol. 15, pp. 593-600 (1996)
  15. Y. H. Berthelot and J. Jarzynski, "Directional Laser Generation and Detection of Ultrasound with Arrays of Optical Fibers," Review of Progress in Quantitative nondestructive Evaluation, Vol. 9, pp. 463-470 (1990)
  16. S. H. Choi, T. H. Nam, K. Y. Jhang and C. S. Kim, "Frequency Response of Narrowband Surface Waves Generated by Laser Beams Spatially Modulated with a Line-arrayed Slit Mask," Journal of the Korean Physical Society, Vol. 60, No. 1, pp. 26-30 (2012) https://doi.org/10.3938/jkps.60.26
  17. A. N. Norris, "Symmetry conditions for third order elastic moduli and implications in nonlinear wave theory," Journal of Elasticity, Vol. 25, No. 3, pp. 247-257 (1991) https://doi.org/10.1007/BF00040928
  18. G. Shui, J. Y. Kim, J. Qu, Y. S. Wang and L. J. Jacobs, "A new technique for measuring the acoustic nonlinearity of materials using Rayleigh waves," NDT & E International, Vol. 41, pp. 326-329 (2008) https://doi.org/10.1016/j.ndteint.2008.01.007

Cited by

  1. Frequency Characteristics of Surface Wave Generated by Single-Line Pulsed Laser Beam with Two Kinds of Spatial Energy Profile Models: Gaussian and Square-Like vol.32, pp.4, 2012, https://doi.org/10.7779/JKSNT.2012.32.4.347
  2. Fully Non-Contact Assessment of Acoustic Nonlinearity According to Plastic Deformation in Al6061 Alloy vol.32, pp.4, 2012, https://doi.org/10.7779/JKSNT.2012.32.4.388
  3. Ultrasonic Nonlinearity of AISI316 Austenitic Steel Subjected to Long-Term Isothermal Aging vol.34, pp.3, 2014, https://doi.org/10.7779/JKSNT.2014.34.3.241