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   Periodicity: 4 times per year   Open access peer reviewed journal

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V. M. Revka^*, L. I. Chyrko

Institute for Nuclear Research, National Academy of Sciences of Ukraine, Kyiv, Ukraine

^*Corresponding author. E-mail address: vrevka@hotmail.com

Abstract: The paper considers the generalized temperature dependence of the stress intensity factor K_JC in the WWER-1000 reactor pressure vessel metal, which was derived based on the surveillance test data for fracture toughness. The consistency of the shape of the Master curve and 95 % upper and lower confidence bounds with the experimental dependence of crack resistance parameters on temperature was studied. From the point of view of the level of conservatism and acceptability, a comparison of the normative curves of fracture toughness according to NPRR (Nuclear Power Rules and Regulations) G-7-002-86 and SOU NNEGC (Standard of organization of Ukraine, National Nuclear Energy Generating Company) 177:2019 with a 5 % confidence bound of the Master curve was carried out. The possibility of using RT₀ temperature as a temperature index instead of T_K for the normative fracture toughness curve of SOU NNEGC 177:2019 was considered.

Keywords: WWER-1000 reactor pressure vessel, 15X2NMFA-A steel, surveillance specimens, radiation embrittlement, critical brittleness temperature, fracture toughness, Master curve.

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