Journal of Central South University

, Volume 18, Issue 3, pp 749–754 | Cite as

Modeling and finite element analysis of transduction process of electromagnetic acoustic transducers for nonferromagnetic metal material testing

  • Kuan-sheng Hao (郝宽胜)Email author
  • Song-ling Huang (黄松岭)
  • Wei Zhao (赵伟)
  • Ru-jiao Duan (段汝娇)
  • Shen Wang (王珅)


Facing the problems lack of considering the non-uniform distribution of the static bias magnetic field and computing the particle displacements in the simulation model of electromagnetic acoustic transducer (EMAT), a multi-field coupled model was established and the finite element method (FEM) was presented to calculate the entire transduction process. The multi-field coupled model included the static magnetic field, pulsed eddy current field and mechanical field. The FEM equations of the three fields were derived by Garlerkin FEM method. Thus, the entire transduction process of the EMAT was calculated through sequentially coupling the three fields. The transduction process of a Lamb wave EMAT was calculated according to the present model and method. The results show that, by the present method, it is valid to calculate the particle displacement under the given excitation signal and non-uniformly distributed static magnetic field. Calculation error will be brought about if the non-uniform distribution of the static bias magnetic field is neglected.

Key words

metal material nondestructive testing electromagnetic acoustic transducer multi-field coupling Garlerkin method finite element 


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  1. [1]
    WANG Xiang-hong, ZHU Chang-ming, MAO Han-ling, HUANG Zhen-feng. Feasibility analysis for monitoring fatigue crack in hydraulic turbine blades using acoustic emission technique [J]. Journal of Central South University of Technology, 2009, 16(3): 444–450.CrossRefGoogle Scholar
  2. [2]
    HUANG Song-ling, LI Lu-ming, SHI Ke-ren, WANG Xiao-feng. Magnetic field properties caused by stress concentration [J]. Journal of Central South University of Technology, 2004, 11(1): 23–26.CrossRefGoogle Scholar
  3. [3]
    MASAHIKO H., HIROTSUGU O. EMATS for science and industry non-contacting ultrasonic measurements [M]. Boston: Kluwer Academic Publishers, 2003: 1–9.Google Scholar
  4. [4]
    ALERS G A, BURNS L R. EMAT designs for special applications [J]. Materials Evaluation, 1987, 45(10): 1184–1189.Google Scholar
  5. [5]
    DIXON S, EDWARDS C, PALMER S B. Experiment to monitor adhesive cure using electromagnetic acoustic transducers [J]. Insight-Non-Destructive Testing and Condition Monitoring, 1995, 37(12): 969–973.Google Scholar
  6. [6]
    MURAYAMA R, AYAHA K. Evaluation of fatigue specimens using EMATs for nonlinear ultrasonic wave detection [J]. Journal of Nondestructive Evaluation, 2007, 26(2/3/4): 115–122.CrossRefGoogle Scholar
  7. [7]
    SEDLAK P, SIKULA J, LOKAJICEK T, MORI Y. Acoustic and electromagnetic emission as a tool for crack localization [J]. Measurement Science and Technology, 2008, 19(4): 45701.CrossRefGoogle Scholar
  8. [8]
    THOMPSON R.B. Noncontact transducers [C]// Ultrasonics Symposium Proceedings. New York: IEEE, 1977: 74–83.Google Scholar
  9. [9]
    LUDWIG R, YOU Z, PALANISAMY R. Numerical simulations of an electromagnetic acoustic transducer-receiver system for NDT applications [J]. IEEE Transactions on Magnetics, 1993, 29: 2081–2089.CrossRefGoogle Scholar
  10. [10]
    JAFRI-SHAPOORABADI R, KONRAD A, SINCLAIR A N. Comparison of three formulations for eddy-current and skin effect problems [J]. IEEE Transactions on Magnetics, 2002, 38: 617–620.CrossRefGoogle Scholar
  11. [11]
    JAFRI-SHAPOORABADI R, KONRAD A, SINCLAIR A N. Computation of current densities in the receiving mode of electromagnetic acoustic transducers [J]. Journal of Applied Physics, 2005, 97(10): 100–106.CrossRefGoogle Scholar
  12. [12]
    KALTENBACHER M, FTTINGER K, LERCH R, TITTMANN B. Finite element analysis of coupled electromagnetic acoustic systems [J]. IEEE Transactions on Magnetics, 1999, 35: 1610–1613.CrossRefGoogle Scholar
  13. [13]
    JIAN X, Dixon S, GRATTAN K T, EDWARDS R S. A model for pulsed Rayleigh wave and optimal EMAT design [J]. Sensors and Actuators: A, Physical, 2006, 128: 296–30.CrossRefGoogle Scholar
  14. [14]
    EISLEY J G., Mechanics of elastic structures: Classical and finite element methods [M]. Englewood Cliffs: Prentice Hall, 1989: 55–70.Google Scholar
  15. [15]
    JIN J M. The finite element method in electromagnetics [M]. New York: Wiley, 2000: 529–536.Google Scholar

Copyright information

© Central South University Press and Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Kuan-sheng Hao (郝宽胜)
    • 1
    Email author
  • Song-ling Huang (黄松岭)
    • 1
  • Wei Zhao (赵伟)
    • 1
  • Ru-jiao Duan (段汝娇)
    • 1
  • Shen Wang (王珅)
    • 1
  1. 1.State Key Laboratory of Power Systems, Department of Electrical EngineeringTsinghua UniversityBeijingChina

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