Detection of high-order Lamb waves using an end-face injection of ultrasonic pulses

Abstract

Abstract In this work, we report the time-of-flight detection of high-order Lamb waves by using an end-face injection of ultrasonic pulses in plates. We used two piezoelectric transducers attached to the opposite edges of a rectangular plate. We applied the Short Time Fourier Transform (STFT) to determine the time-of-flight. We compare the contours of the STFT on the time-frequency spectrogram with the theoretical time-of-flight. This technique defines a broadband map for multiple Lamb waves on the same experimental run. We have found clear evidence not only of the lowest symmetric and antisymmetric modes ( S 0 and A 0 ) but also of higher order modes ( S 1 , A 1 , and S 2 ).