Investigation of frequency-dependent attenuation coefficients for multiple solids using a reliable pulse-echo ultrasonic measurement technique

Abstract

A well-established narrowband pulse-echo technique is employed and improved further to investigate the frequency-dependent ultrasonic wave attenuation in various solids. During attenuation coefficient measurement, the diffraction correction is introduced to minimize wave beam-spreading loss, and frequency domain signals are used to minimize both the effects of downward shift of frequency and the error in determining the amplitude of time-domain signals. The frequency-dependent attenuation curves for 19 frequently-used solid materials are obtained using this method in the frequency range 1–25 MHz. It is observed from the measurement results of these materials that the attenuation can vary linearly or nonlinearly with the signal frequency, and the potential impact factors of the attenuation-frequency relationship are discussed. The experimental results presented in this paper is expected to provide a good reference for researchers interested in developing and using frequency-dependent attenuation coefficients of materials that are currently missing in the literature.