Electromagnetic Ultrasonic Transducers
Direct electromagnetic generation is a relatively recent addition to the list of techniques available for the generation of ultrasonic waves for nondestructive evaluation purposes. The history and physics of the generation technique will be discussed. In addition, transducer designs for the generation of various types of sound waves (longitudinal, shear and surface) will be presented. In particular, surface wave transducer designs will be shown to be very similar to those used in piezoelectric SAW devices. This similarity has been exploited to obtain EM transducers with signal processing capabilities similar to the piezoelectric devices. Other applications of these devices as well as possible directions of future research efforts will be discussed.
KeywordsRayleigh Wave Surface Acoustic Wave Static Magnetic Field Piezoelectric Transducer Bulk Wave
Unable to display preview. Download preview PDF.
- 1.Aksenov, S.I., B.P. Vikin and K.V. Vladimirskii, “The Excitation of Ultrasonic Vibrations by Ponderomotive Forces”, J. Exper. Theoret. Phys. USSR, 28 (1955) 762. (Eng. Trans. - Sov. Phys. JETP, 1, 1955 p. 609 )Google Scholar
- 2.Gantmakher, V.F. and V.T. Dolgopolov, “Excitation of Standing Sound Waves in Bi by an Electromagnetic Method”, Sov. Phys. JETP Lett., 5 (1967) 12. (Eng. Trans.)Google Scholar
- 6.Grubin, H.L., “Direct Electromagnetic Generation of Compressional Waves in Metals in Static Magnetic Fields”, IEEE Trans. on Sonics and Ultrasonics, SU-17 (1970) 227.Google Scholar
- 8.See: E.R. Dobbs, “Electromagnetic Generation of Ultrasonics”, Physical Acoustics, Vol. X, W.P. Mason and R.N. Thurston, eds., Academic Press, New York, 1973. Chapter 3 and the references contained therein.Google Scholar
- 9.Maxfield, B.W. and J.K. Hulbert, “Electromagnetic Acoustic Wave Transducers (EMATS): Their Operation and Mode Patterns”, Proc. 10th Symp. on NDE, San Antonio, Texas, April 1975, p. 44.Google Scholar
- 10.Thompson, R.B., “A Model for the Electromagnetic Generation and Detection of Rayleigh and Lamb Waves”, IEEE Trans on Sonics and Ultrasonics, SU-20 (1973) 340.Google Scholar
- 11.Kawashima, K. and R.W. McClung, “Electromagnetic Ultrasonic Transducer for Generating and Detecting Longitudinal Waves (with a Small Amount of Radially Polarized Transverse Wave)”, Mat. Eval., 34 (1976) 81.Google Scholar
- 12.Burstein, E., H. Talaat, J. Schoenwald, J.J. Quinn and E.G.H. Lean, “Direct EM Generation and Detection of Surface Elastic Waves on Conducting Solids I. Theoretical Considerations”, Proc. 1973 IEEE Ultrasonics Symp., Cat. No. 73, CHO 807-8 SU, p. 564, 1973.Google Scholar
- 14.Frost, H.M., J.C. Sethares and T.L. Szabo, “Applications for New Electromagnetic SAW Transducers”, 1975 Ultrasonics Symposium Proc., IEEE Cat. No. 75 CHO 994-SU, 604, 1975.Google Scholar
- 16.Szabo, T.L., “Advanced SAW Electromagnetic Transducer Design”, 1976 Ultrasonics Symposium Proc., IEEE Cat. No. 76 CH1120- 5SU, 29, 1976.Google Scholar
- 17.Moran, T.J., “Use of Pulse Compression Techniques to Improve the Range Resolution of Electromagnetic Surface Wave Transducers”, 1976 Ultrasonics Symposium Prog., IEEE Cat. No.76 CH1120-5SU, 26, 1976.Google Scholar
- 18.Moran, T.J. and R.M. Panos, “Electromagnetic Generation of Electronically Steered Ultrasonic Bulk Waves”, J. Appl. Phys., 47 (1976) 2225.Google Scholar