Abstract
A new ultrasonic transducer with multi-belts coil for generating and receiving longitudinal guided wave in ferromagnetic material pipes is proposed. The theory backgrounds and transduction principle of the proposed transducer are presented and analyzed. To verify the performance of the transducer, several experiments are performed. The performance of inspecting crack, frequency-tuned characteristic, effect of bias static magnetic field and dynamic magnetic field, lift-off effect and effect of the period number of the exciting current are investigated. The results show that the proposed coils not only could tune the center frequency but also could improve the amplitude and signal-to-noise (SNR) of the detected signals. Bias static magnetic field and dynamic magnetic field are two important factors influencing the amplitude of the longitudinal guided wave. The amplitude of the longitudinal guided wave is exponentially decreased versus the lift-off distance of the transmitter and receiver. Period number of excitation signal could influence the amplitude and wave width of the ultrasonic wave. The proposed transducer could easily control the wave modes and would be a better choice for pipes’ monitoring and inspection compared to traditional single-belt coil transducer.
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References
Alleyne D N, Cawley P. Long-range propagation of Lamb waves in chemical plant pipe work. Mat Eval, 1997, 55: 504–508
Kwun H, Teller C M. Magnetostrictive generation and detection of longitudinal, torsional, and flexural waves in a steel rod. J Acoust Soc Am, 1994, 96: 1202
Kwun H, Holt A E. Feasibility of under-lagging corrosion detection in steel pipe using the magnetostrictive sensor technique. NDT and E Int, 1995, 28: 211–214
Kwun H, Dynes C. Long-range guided wave inspection of pipe using the magnetostrictive sensor technology-Feasibility of defect characterization. Proceedings of SPIE, 1998, 3398: 28–34
Thompson R B. New configurations for the electromagnetic generation SH waves in ferromagnetic materials. Ultrasonic Symposium Proceedings, IEEE, New York, 1978. 374–378
Hao K S, Huang S L, Zhao W, et al. A new frequency-tuned longitudinal wave transducer for nondestructive inspection of pipes based on magnetostrictive effect. IEEE Sensors Application Symposium, 2010, 64–68
Murayama R, Mizutani K. Conventional electromagnetic acoustic transducer development for optimum Lamb wave modes. Ultrasonics, 2002, 40: 491–495
Rose J L. Ultrasonic Waves in Solid Media. New York: Cambridge University Press, 1999. 101–130
IEEE standard 319-1990. IEEE standard on magnetostrictive materials: piezomagnetic nomenclature, 1990
Sepandarmaz M. Determination of piezomagnetic properties for a magnetostriction-based EMAT. Ph.D. Dissertation, Toronto: University of Toronto. 2008. 19–25
Wang Y M, Kang Y H, Wu X J. Theoretical and experimental study on generation of longitudinal guided waves in circular pipes based on magnetostrictive effect (in Chinese). Chin J Mech Eng, 2005, 41: 174–179
Sablic M J, Rubin S W. Modeling magnetostrictive generation of elastic waves in steel pipes, I. Theory. Int J Appl Electrom, 1999, 10: 143–166
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Hao, K., Huang, S., Zhao, W. et al. Multi-belts coil longitudinal guided wave magnetostrictive transducer for ferromagnetic pipes testing. Sci. China Technol. Sci. 54, 502–508 (2011). https://doi.org/10.1007/s11431-010-4189-8
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DOI: https://doi.org/10.1007/s11431-010-4189-8