Ultrasonic inspection of tilted defects using the 'corner effect' - modelling and experimental validation

摘要

In ultrasonic NDT, the 'corner trap'mechanism is a common means of detecting planar cracks which break the back-wall surface of the component. The mechanism is most efficient when the crack is normal or near-normal to the back wall, so that a specular reflection is obtained. However, a response is still obtained when the crack is more tilted, due to diffracted edge wave signals from the crack tip and from the 'wedge' formed between the crack and the back wall.