Investigation of the dispersion relations of surface acoustic waves propagating on a layered cylinder

The propagation of pulsed surface acoustic waves (SAW) on a layered cylinder has been investigated both theoretically and experimentally. The pulses were generated by a ''line-source'' pulsed laser and detected by an optical beam deflection technique providing information on pulse dispersion in a fully contactless way. The sample investigated was a hollow steel tube fitted tightly to a massive cylinder of a tin alloy. The theoretical dispersion relation for surface waves propagating in this system, under the assumption that the wave fields are uniform along the cylinder axis, was derived and good agreement with the experimental results was found. These results confirm the applicability of an optical, contactless technique for the characterization of layers on curved substrates. (C) 1996 Acoustical Society of America.