Stability of the Y–Ti–O oxides in reactor materials under neutron irradiation at high temperatures
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Published:2022-11-01
Issue:3(111)
Volume:
Page:109-130
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ISSN:1994-6716
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Container-title:Voprosy Materialovedeniya
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language:
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Short-container-title:Vopr. materialoved.
Author:
Frolov A. S.1, Kuleshova E. A.2, Gurovich B. A.1, Nikitina A. A.3, Maltsev D. A.1, Fedotova S. V.1, Safonov D. V.1
Affiliation:
1. National Research Center “Kurchatov Institute” 2. National Research Center “Kurchatov Institute”; National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) 3. A.A. Bochvar High Technology Scientific Research Institute for Inorganic Materials (VNIINM)
Abstract
The paper presents the results of electron microscopic studies of ferrite-martensitic steel samples hardened with Y-O oxides, EP-450 DUO in the initial state and after neutron irradiation in the BN-600 reactor at 1000°C to a damaging dose of 77.5 dpa. These studies showed that the main types of oxide phases were Y2(Si, Ti)2O7 and Y2(Si, Ti)O5. These precipitates at sizes less than 10-20 nm were semi-coherent with a ferritic matrix of steel EP-450 DUO with the ratio (110)malrix//(221)palticle. Some of the Y-Ti-O oxides in the initial state were Y2Ti2O7-type with some deviations from the stoichiometric composition.However, after neutron irradiation under BN-600 conditions at temperature ~ 1000°C, oxide particles could not be described by the indicated stoichiometry. Besides, after irradiation, silicon and aluminum were found in the oxide's composition. In the case of taking these elements into account during the construction of a triple composition diagram, it was shown that the oxide phases had Y2(Ti, Si, Al)2O7 and Y2(Ti, Si, Al)O5 types. It was established that in samples of EP-450 DUO steel in the initial state with oxide particles up to 20 nm in size, the yttrium content is generally lower than the titanium concentration. The titanium and yttrium concentrations corresponded to the stoichiometric composition Y2Ti2O7 (1:1) with a further increase in the average diameter of these phases. After irradiation, the situation changed somewhat: the yttrium content in most oxide phases exceeds the total concentration of titanium, silicon, and aluminum.The paper also presents the analysis of porosity and evolution of grain structure in EP-450 DUO steel after neutron irradiation.
Publisher
FSUE CRISM Prometey
Subject
General Earth and Planetary Sciences,General Environmental Science
Reference29 articles.
1. Wharry, J.P., Swenson, M.J., Yano, K.H., A review of the irradiation evolution of dispersed oxide nanoparticles in the b.c.c. Fe-Cr system: Current understanding and future directions, J. Nucl. Mater., 2017, V. 486, pp. 11-20. 2. Allen, T.R., Gan, J., Cole, J.I., Miller, M.K., Busby, J.T., Shutthanandan, S., Thevuthasan, S., Radiation response of a 9 chromium oxide dispersion strengthened steel to heavy ion irradiation, J. Nucl. Mater., 2008, V. 375, No 1, pp. 26-37. 3. Chen, T., Gigax, J.G., Price, L., Chen, D., Ukai, S., Aydogan, E., Maloy, S.A., Garner, F.A., Shao, L., Temperature dependent dispersoid stability in ion-irradiated ferritic-martensitic dualphase oxide-dispersion-strengthened alloy: Coherent interfaces vs. incoherent interfaces, Acta Mater., 2016, V. 116, pp. 29-42. 4. Auger, M.A., Hoelzer, D.T., Field, K.G., Moody, M.P., Nanoscale analysis of ion irradiated ODS 14YWT ferritic alloy, J. Nucl. Mater., 2020, V. 528. 5. Lescoat, M.-L., Ribis, J., Chen, Y., Marquis, E.A., Bordas, E., Trocellier, P., Serruys, Y., Gentils, A., Kaitasov, O., de Carlan, Y., Legris, A., Radiation-induced Ostwald ripening in oxide dispersion strengthened ferritic steels irradiated at high ion dose, Acta Mater., 2014, V. 78, pp. 328-340.
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