Acoustic emission inspection of large test components including various defects

Extensive Acoustic emission tests were performed on large test components with built-in flaws. The results of hydrotests demonstrate the ability of AE as an integral NDT method to detect and localize flaws, and to classify macroscopic crack growth. A clear influence of PWR operating conditions on the AE intensity of stationary flaws was found during subsequent hydrotests. AE during cylic load was characterized by recurring signals at specific load levels. Non-growing cracks emitted signals at certain few intermediate loads showing the reproducibility of AE as an effect of friction processes. Growing cracks were determined by AE near maximum load. Improved measuring techniques are presented which can lead to a better location accuracy and allow discrimination of flaw position