Abstract
In some case, defects at the corner in L-shaped component of actual structures cannot be detected by the general ultrasonic technique. The goal of this study is developing NDT method which can detect defects at the corner. In this paper, the result of fundamental research using L-shaped aluminum alloy with artificial defects is introduced. 2 type of the specimen were prepared. Type-I has rectangular outer edge and vertical artificial defect at the corner. On the other hand, Type-II has round outer edge and curved artificial defect. The ultrasonic transducer was put on the surface which is away from the corner. When straight-shaped defects vertical to ultrasonic propagation direction are exists, clear flaw-echo was observed. On the other hand, when curved defects are exists, even a little change was observed, clear flaw-echo was not observed. Further studies are required for detecting curved-damages of L-shaped specimen.
