Measurements of backscattered leaky Lamb waves in plates

Abstract

We have reported earlier the observation of backscattered leaky Raleigh waves from a liquid–solid interface [J. Acoust. Soc. Am. 72, 1018–1020 (1982)]. Now we have carried out experiments to observe backscattered leaky Lamb waves from a plate immersed in liquid, using a single transducer in pulse echo modes. Sharp peaks were observed at angles corresponding to backward propagating symmetrical and antisymmetrical Lamb modes. These backward propagating Lamb waves leak back at both sides of the plate.