Attenuation Of Ultrasonic Rayleigh-Lamb Waves By A Symmetrical Embedded Crack In An Elastic Plate

The present paper illustrates how embedded vertical defects can be detected rapidly in sheet metal by using longitudinal ultrasonic waves. Computational methods are used to validate analytical predictions of the reflection coefficients due to the attenuation of such ultrasonic waves by physically small defects. It is shown that detectable attenuation of the lowest order symmetric Rayleigh–Lamb wave (S0) occurs for a range of small defects (sub-millimeter in length) when using high-frequency waves (MHz range).