Dislocation-defect interactions in nuclear reactor pressure-vessel steels investigated by means of internal friction
Faculty of Applied Economics
Engineering sciences. Technology
Journal of alloys and compounds. - Amsterdam
12th International Conference on Internal Friction and Ultrasonic, Attenuation in Solids (ICIFUAS-12), JUL 19-23, 1999, BUENOS AIRES, ARGENTINA
, p. 445-448
University of Antwerp
A study of pressure-vessel steel embrittlement mechanisms by means of temperature-dependent and amplitude-dependent internal friction has been carried out within the framework of commercial surveillance of nuclear reactor components. An inverted torsion pendulum operating at similar to 1 Hz has been employed to study a wide variety of pressure-vessel steels and an IAEA reference material in various conditions, This contribution will discuss the results for the JRQ reference material only and serve as a basis on which to interpret the data from real pressure-vessel steels. The temperature-dependent experiments evidence a reduction in the dislocation mobility as a result of neutron irradiation and prove that the technique is sensitive to thermal ageing involving changes in the dislocation mobility and type of dislocation-defect interaction. Amplitude-dependent internal friction provides a means to determine the yield strength of the material. The importance of the influence of dislocation dragging on the yield stress is highlighted. (C) 2000 Elsevier Science S.A. All rights reserved.