Ядерна фізика та енергетика Nuclear Physics and Atomic Energy   ISSN: 1818-331X (Print), 2074-0565 (Online)   Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine   Languages: Ukrainian, English, Russian   Periodicity: 4 times per year   Open access peer reviewed journal

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M. G. Holiak¹, G. P. Grynchenko², V. M. Revka¹, O. V. Trygubenko^1,2,*, Yu. V. Chaykovskyi¹, L. I. Chyrko¹, O. V. Shkapyak<sup>1

1</sup> Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine
² SS “Scientific and Technical Center”of SE “NNEGC “Energoatom”, Kyiv, Ukraine

^*Corresponding author. E-mail address: trygubenko_ol@ukr.net

Abstract: The results of surveillance-specimens testing of re-irradiated after recovery annealing reactor pressure vessel (RPV) metal of Rivne NPP unit 1 are presented. The radiation strengthening and shift of critical temperature of brittleness for RPV base metal and weld metal have been defined using tension and Charpy impact tests. The comparison of the experimental results and irradiation re-embrittlement models has been made. Based on summary analysis of three surveillance-specimens sets test results, it is shown that re-embrittlement degree after recovery annealing is not higher than that under primary irradiation. The paper also reveals the effect of phosphorus content in the RPV weld metal on Charpy upper shelf energy.

Keywords: WWER-440 reactor pressure vessel, recovery annealing, surveillance-specimens, radiation embrittlement, critical temperature of brittleness, Charpy curve, upper shelf energy.

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