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.
KeywordsPermeability Attenuation Propa Radar Acoustics
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