THE VERTICAL ATTENUATION AND TOMOGRAPHY OF RAYLEIGH-WAVES

The formula of vertical energy attenuation of Rayleigh waves in a semi -infinite substrate with a fluid layer has been derived. It was tested and verefied by ultrasonic experiments on thick aluminum plates with long man-made slots. A quantitative agreement was obtained between exp eriment and theory. Moreover, tomographic experiments were performed. The tomographic image can provide information concerning not only the two-dimension location and nature of defects, but also the position of defects in the vertical direction. (C) 1998 Elsevier Science B.V. All rights reserved.