Abstract
Using statistical modeling (Monte Carlo method), numerical experiments were performed to determine the critical temperature Tc of brittleness according to the PNAE G-7-002-86 and RD EO 0598-2004 methodologies. The data of the Charpy impact test (V-notched) used in the calculations were obtained using more than 1200 samples of 15Kh2NMFAA steel cut from various zones along the thickness, height, and circumferential direction of the VVER-1000 reactor vessel. The tests were carried out in the temperature range from –95 to +20°C. On the basis of statistical criteria, we show that the shell material of the reactor vessel can be considered as homogeneous. The values of the destruction energy of impact samples in the brittle-viscous transition region are found to be distributed according to a bimodal law. The distribution parameters are determined at various temperatures. Using the statistical modeling, the distribution laws of the critical temperature of brittleness are determined. The average values of Tc obtained using PNAE G-7-002-86 are shown to be approximately 10°C higher than those obtained using RD EO 0598-2004. We determined the boundaries of the intervals in which the values of the critical temperature of brittleness with 90% probability fall depending on the number of samples tested and the test scheme. Recommendations for improving the methodology of determining the critical temperature of brittleness are given.
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REFERENCES
RD 0598-2004. Metodika opredeleniya kriticheskoi temperatury khrupkosti materialov korpusov reaktorov po rezul’tatam ispytanii malorazmernykh obraztsov na udarnyi izgib (RD 0598-2004. Measuring the Critical Temperature of Brittleness of RPV Materials Using Results of Impact Tests of Small-Size Samples), Moscow: Rosenergoatom, 2004.
PNAE G-7-002-86. Pravila i normy v atomnoi energetike. Normy rascheta na prochnost’ oborudovaniya i truboprovodov atomnykh energeticheskikh ustanovok (PNAE G‑7-002-86. Rules and Standards in Nuclear Energetics. Standards of Calculation for Durability of Equipment and Pipelines for Nuclear Power Installations), Moscow: Energoatomizdat, 1989.
Stepnov, M.N., Veroyatnostnye metody otsenki kharakteristik mekhanicheskikh svoistv (Probabilistic Methods for Evaluation of the Characteristics of the Mechanical Properties), Novosibirsk: Nauka, 2005.
Kazantsev, A.G., Markochev, V.M., and Sugirbekov, B.A., Evaluation of errors of determination of the critical temperature of metal brittleness of cases of VVER-1000 case, Tyazh. Mashinostr., 2015, no. 10, pp. 19–27.
Davidenkov, N.N., Dinamicheskie ispytaniya metallov (Dynamic Testing of Metals), Moscow: Narkomat Tazh. Prom. SSSR, 1936.
Shevandin, E.I. and Razov, I.A., Khladnolomkost’ i predel’naya plastichnost’ metallov v sudostroenii (Cold Brittleness and Maximum Plasticity of Metals in Ship-Building Industry), Leningrad: Sudostroenie, 1965.
Kantor, M.M. and Bozhenov, V.A., Scattering of values of impact toughness of low-alloy steel in the ductile-brittle transition temperature region, Inorg. Mater.: Appl. Res., 2014, vol. 5, no. 4, pp. 293–302.
Markochev, V.M. and Aleksandrova, O.V., Fractional power function in description of the probability, Zavod. Lab., Diagn. Mater., 2012, vol. 78, no. 11, pp. 71–73.
Buslenko, N.P. and Shreider, Yu.A., Metod statisticheskikh ispytanii (Monte-Karlo) i ego realizatsiya v tsifrovykh mashinakh (Method of Statistical Tests (Monte Carlo) and Its Implementation in Digital Machines), Moscow: Fizmatlit, 1961.
Chernobaeva, A.A., Nikolaev, Yu.A., Skundin, M.A., Zhurko, D.A., Krasikov, E.A., Medvedev, K.I., Kostromin, V.N., Drobkov, G.V., and Ryasanov, S.V., Data scatter cause analysis of the temperature surveillance specimens of VVER-1000 metal, J. At. Energy, 2012, vol. 113, no. 6, pp. 337–344.
Chernobaeva, A.A., Kuleshova, E.A., Skundin, M.A., Maltsev, D.A., Chirko, L.I., and Revka, V.N., Revision of date base of VVER-1000 thermal aging surveillance specimens, Proc. 22nd Int. Conf. on Structural Mechanics in Reactor Technology (SMiRT 22), San-Francisco, Raleigh, NC: Int. Assoc. Struct. Mech. Reactor Technol., 2013, pp. 138–147.
Chernobaeva, A.A., Verification of the models of radiation embrittlement of RPV materials and procedures of their application to evaluate operated reactor pressure vessels, Doctoral (Eng.) Dissertation, Moscow, 2009.
RD EO 1.1.2.0.0789-2012. Metodika opredeleniya vyazkosti razrusheniya po rezul’tatam ispytanii obraztsov-svidetelei dlya rascheta prochnosti i resursa korpusov reaktorov VVER-1000 (RD EO 1.1.2.0.0789-2012. Measuring the Destruction Viscosity Using the Results of Tests of Samples for Calculation of the Strength and Capacity of VVER-1000 Reactor Cases), Moscow: Rosenergoatom, 2012.
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Kazantsev, A.G., Markochev, V.M. & Sugirbekov, B.A. Statistical Estimate of Determining the Critical Temperature of Brittleness for Metal of the VVER-1000 Reactor Vessel Using Impact Bending Test Data. Inorg Mater 54, 1523–1531 (2018). https://doi.org/10.1134/S0020168518150074
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DOI: https://doi.org/10.1134/S0020168518150074