Ultrasonic Methods to Study Shadow Boundaries of Diffracting Cracks. Ultrasonic Caustics in NDE (Non-Destructive Evaluation)

摘要

The formation of caustics due to the defraction of ultrasound is predicted theoretically and observed experimentally in the shadow region of elliptical discontinuities in material. Good agreement is obtained between experiment and theory. It is suggested to use this method to determine size and orientation of cracks in structural materials, which is an important problem in non-destructive evaluation. (Author)