Primary calibration by reciprocity method of high-frequency acoustic-emission piezoelectric transducers

Although acoustic-emission (AE) piezoelectric transducers have distinctive variations in sensitivity, depending on frequency, propagation medium, and coupling, the vast majority of AE research is conducted by utilizing uncalibrated AE transducers. As a consequence, most results obtained by different groups are not comparable among each other. In this work, primary calibration by the method of reciprocity is shown. Rayleigh and longitudinal wave calibration curves are presented for piezoelectric high-frequency broadband transducer, mounted on steel and aluminium, in the frequency range 300 kHz-4 MHz. Influences on primary calibration of AE transducers, namely, by coupling medium, contact pressure, and propagation medium, are investigated.