| 摘要 |
PURPOSE:To surely detect a defective part on a material boundary surface by making an ultrasonic wave perpendicularly incident on the material boundary surface and comparing the attenuation of the multi-reflected echo of the ultrasonic wave with a preliminarily obtained multi-reflected echo attenuation curve of an indefectible part on the material boundary surface. CONSTITUTION:An ultrasonic wave is made perpendicularly incident on a material boundary surface 3 of a member 2 like a clad material, which consists of members A and B different in material from each other, from an ultrasonic probe 1. The reflected echo from the surface 3 is not only partially propagated to the probe 1 but also repeatedly reflected in the member 2 to become the multi-reflected echo, and this echo is detected by the probe 1 to obtain a hard copy. It is compared with a preliminarily obtained hard copy of the indefectible part, and a peeling part is decided if the obtained hard copy is on the outside of an error range. Consequently, peeling of the material boundary surface or a contact-defective part is surely detected. |
