Absorption of Rayleigh Waves in Low-Loss Media

Abstract

Many materials are characterized by internal dissipation parameter 1/Q«1. An expression is derived for such media relating the Rayleigh wave absorption coefficient to compressional and shear wave absorption coefficients with the elastic velocities as parameters. Ultrasonic experiments are described in which the three absorption coefficients are measured in thin Plexiglas sheets. The theoretically derived expression satisfactorily relates the observed absorption coefficients.