Detection of Small Horizontal Defects in Thin Isotropic Plates Using Ultrasonic Rayleigh-Lamb Waves
نویسنده
چکیده
This paper considers the detection of symmetric crack-like defects in thin metallic plates using longitudinal ultrasonic waves. Only physically small defect sizes are considered in order that the initial stages of crack growth, for example during fatigue, can be detected. This method has the potential to be significantly faster for non-destructively detecting defects than conventional ultrasonic techniques, which rely on transverse waves propagating through the thickness of a plate. It is shown, using analytical and computational methods, that it is possible to obtain measurable reflection coefficients due to the attenuation of a longitudinal ultrasonic wave by physically small defects.
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