engleski

The multiparameter-POD applied in detection of the defects in the environment of nonhomogeneous ultrasound attenuation

A phased array ultrasonic system is applied for testing copper specimens manufactured with artificial flat-bottom holes. This setup is tested in turns of the development of an optimized inspection technique for copper canisters for the final disposal of nuclear waste in Sweden. The inspected copper specimens are characterized by having non-homogeneous ultrasound attenuation. A new method in assessing the POD, the multiparameter-POD, is employed for estimating the reliability of detection of the artificial defects. The multiparameter-POD applied to the signal response analysis combines the assessed local ultrasound attenuation with the dependence on depths and areas of the flat-bottom holes. The presented method accounts for the more complex physical interaction of the sound wave with a specimen. The features of the multiparameter-POD are discussed at a selected UT configuration using 3.5 MHz. The dependence of the UT-signals and hence the POD on the local attenuation turned out to be a crucial influence on the inspection reliability in addition to the defect depth and area.

POD, defects in copper, ultrasound

The Review of Progress in Quantitative Nondestructive Evaluation (QNDE)