J. Phys. IV France 02 (1992) C1-629-C1-632
INFLUENCE DES CONDITIONS DE COUPLAGE D'UN INTERFACE SUR LA FORME DU SIGNAL IMPULSIONNELY. JAYET, J.C. BABOUX and M. PERDRIX
Laboratoire de Traitement du Signal et Ultrasons, INSA, Bât. 502, F-69621 Villeurbanne cedex, France
Numerous theoretical studies have shown that the reflection and transmission phenomena of an ultrasonic plane wave can be expressed by complex coefficients depending on the acoustic properties of the different media and on the coupling conditions of the interface. In pulsed mode, the application of these complex coefficients changes the shape of the signal. Then, for a given incident shear wave, we study the influence of the quality of the interface, characterized by boundaries coefficients, on the shape of the reflected shear wave. So, we have proven that the quality of the interface cannot be determined only from the amplitude of the reflected signal but, we must consider its shape depending on the argument of reflection coefficient.
© EDP Sciences 1992