Theoretical and experimental approach of reconstruction of defect sizes and structures

This report discusses some of those methods which proved recently to be very promising. One of the most important automatic testing methods of reactor components is the tandem method. For this method a program has been developed allowing to optimize the division of walls with any thickness according to the RSK-rules. As a special case we can obtain the inclination angle of the flaws. A new tool is the excitation of shear waves by the aid of an electrodynamic transducer. Here the angle can be chosen by electronically varying the frequency. A comparison is made between the reconstruction capability by using focusing probes with the focal plane in the plane of the flaws and with the reconstructions received from ultrasonic holography. The experimental results with focal probes are represented in a three-dimensional image. The advantage of the holography lies in the investigation of greater depths