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

摘要

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 frequencydependent attenuation coefficients of materials that are currently missing in the literature.