Results of post-irradiation examination of WWER fuel assembly structural components made of E110 and E635 alloys

Full text: The paper presents the main examination results on the condition of fuel rods, guide tubes and spacer grids of the WWER FA made of E-110 and E-635 alloys. The paper is based on the data obtained during the examination of 28 WWER-1000 FA and 12 WWER-400 FA. Taking into account the high effect of the zirconium alloy behavior in the water-cooled reactors on the competence of Russian fuel, the comparison of Russian alloys with those of the zircaloy and M5 type was performed. It is shown that under the normal operating conditions the E-110 alloy proved to be suitable material for the WWER fuel rod claddings. The E-635 alloy is used, mainly, in the WWER-1000 FA skeleton elements. The registered oxide film thickness on the elements made of this alloy is higher as compared to the E-100 alloy. Nevertheless, it does not influence much on the serviceability of the bearing elements of the WWER-1000 FA skeleton. (author)