TEM Examinations of the Metal-Oxide Interface of Zirconium Based Alloys Irradiated in a Pressurized Water Reactor

    Volume 2, Issue 6 (June 2005)

    ISSN: 1546-962X

    CODEN: JAIOAD

    Published Online: 1 June 2005

    Page Count: 25


    Abolhassani, S
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Restani, R
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Rebac, T
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Groeschel, F
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Hoffelner, W
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Bart, G
    Paul Scherrer Institut, Laboratory for Materials Behaviour,

    Goll, W
    Framatome ANP GmbH, Erlangen,

    Aeschbach, F
    Kernkraftwerk Gösgen-Däniken,

    (Received 3 May 2004; accepted 6 December 2004)

    Abstract

    Metal-oxide interfaces of three different materials irradiated in a pressurized water reactor have been analyzed by TEM and AEM. Standard Zircaloy-4, low-tin Zircaloy-4, and Zr-2.5%Nb were used for this study. The microstructure of the material on the two sides of the metal-oxide interface, the geometry of the interface, the distribution of different alloying elements, and the oxygen profile have been examined in each material. Results of the examinations showed that the three materials had different microstructure and oxygen distribution on the two sides of the metal-oxide interface. In particular, the following parameters were noticed: a) the geometry of the interface seems to be of a different nature in the case of Zr-2.5%Nb alloy. Unlike the Zircaloy-4 alloys, which show an undulated interface, this material has a “jigsaw” type interface. This point is discussed, and its role on the oxidation is considered. b) Hydrides are observed and analyzed in the vicinity of the interface in the case of low-tin Zircaloy-4, and it is shown that they can have an influence on the occurrence of cracks in this material. c) The origins of stress are discussed, and it is shown that it can have different sources. The crystal structure of the oxides is mainly monoclinic. A tetragonal oxide is observed at some regions, in particular in the standard Zircaloy-4.


    Paper ID: JAI12390

    DOI: 10.1520/JAI12390

    ASTM International is a member of CrossRef.

    Author
    Title TEM Examinations of the Metal-Oxide Interface of Zirconium Based Alloys Irradiated in a Pressurized Water Reactor
    Symposium Zirconium in the Nuclear Industry: Fourteenth International Symposium, 2004-06-15
    Committee B10