Industrial Applications of Positron Annihilation
J. Phys. IV France 05 (1995) C1-127-C1-134
Application of the Positron Lifetime Spectroscopy as Method of Non-Destructive TestingB. Somieski1, R. Krause-Rehberg2, H. Salz2 and N. Meyendorf1
1 Fraunhofer-Institut für zerstörungsfreie Prüfverfahren, Abt. EADQ, Gruppe phys. Verfahren Universität, Gebäude 37, 66123 Saarbrücken, Germany
2 Martin-Luther-Universität Halle/Wittenberg, Fachbereich Physik, Positronenlabor, F. -Bach-Platz 6, 06108 Halle/Saale, Germany
In order to show the suitability of the Positron Lifetime Spectroscopy (POLIS) as a method of Non-Destructive Testing (NDT) several iron alloys / steels were mechanically damaged (tensile stress, fatigue, creeping). The positron annihilation parameters show clear changes during all applied kinds of damage. After tensile stress as well as after creeping a homogeneous distribution of damage in the sample was detected. During the very first elastic cycle of a fatigue experiment, a change in the defect structure occurs in well annealed materials. A modified spectrometer for in the field mapping is presented.
© EDP Sciences 1995