Improved ultrasonic spectroscopy methods for characterization of dispersive materials.

Transmission ultrasonic spectroscopy method has been successfully implemented for the characterization of piezoceramics at high frequencies. There are, however, still some intrinsic error sources that limit the accuracy of the method. In this paper, two improved ultrasonic spectroscopy methods are presented, which can reduce the number of pre-required parameters and reduce another error source. The two improved methods were used to measure the frequency dispersion of phase velocity and attenuation of doped piezoceramic lead zirconate titanate (PZT-5A); results were compared with those obtained from the conventional method. The advantages and limitations of each method are discussed.