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Information × Registration Number 0224U033290, (0123U102776) , R & D reports Title Development of the advanced neutron-absorbing materials for control rods with extended resource popup.stage_title Матеріалознавчі дослідження нейтронно-поглинаючих матеріалів і нейтронно-фізичні розрахунки для обргунтування їх ресурсу і працездатності в умовах роботи в реакторі ВВЕР-1000 при нормальній експлуатації і аварійних ситуаціях Head Krasnorutskyi Volodymyr S., Кандидат фізико-математичних наук Registration Date 24-12-2024 Organization "Nuclear Fuel Cycle" Science and Technology Establishment National Science Center"Kharkov Institute of Physics & Technology" National Academy of Science,Ukraine popup.description1 Development of the advanced neutron-absorbing materials based on combinations of elements such as hafnium, zirconium and rare earth elements, technology for manufacturing dense pellets, as well as out-of-pile testing and material science research to develop and substantiate the design of control rod with an absorber combined in height, which will increase the resource and reliability of operation under normal and beyond design conditions of both operating VVER-1000 reactors and prospective AP1000 reactors that will form the basis of nuclear industry in Ukraine. popup.description2 Scientific and technological basis for the development of neutron absorbing materials in the form of complex oxygen systems, such as dysprosium hafnate and dysprosium zirconate in a single-phase state (fluorite type), promising for use in absorber rods for various types of reactors, was developed. Such materials in pellet and powder forms can be used to create both “black” and “gray” control rods for VVER-1000 and new reactor types to be introduced into Ukraine's nuclear power industry, including small modular reactors. Materials science investigations of phase and elemental composition, density, microstructure, both in the initial state and after long-term corrosion tests were performed. The results of corrosion tests of REE hafnate and zirconate pellets in simulated VVER-1000 coolant medium with T=350 °C and P=16.5 MPa (up to 5000 hours) substantiated their high corrosion resistance. The mechanical characteristics of dysprosium hafnate pellets with a density of (8.1...8.4) g/cm3 in the initial state and after long-term corrosion tests were investigated. It was confirmed that the materials retain full compatibility with 42ХНМ alloy under VVER-1000 emergency conditions when overheated in water vapor in the temperature range of (800...1200) °С. The calculations show that dysprosium hafnate in pellet form with a diameter of 6.85 mm and a density of 8.0 g/cm3 in 42ХНМ alloy cladding will have an initial relative physical efficiency of neutron absorption of about 84%. It was shown that the n, γ reaction changes the chemical and isotopic composition of the neutron absorbing material. It was demonstrated that the temperature on the surface and in the center of dysprosium hafnate pellets at an energy release of 122.74 W/cm3 was 389.6 °C and 588.6 °C, respectively. Thus, the results of research and testing enable us to recommend further development of materials in the form of dysprosium hafnate to create absorber rods for new advanced VVER-1000 reactor cycles. Product Description popup.authors Bondarenko Serhii L. Byrlov Volodumur V. Hrytsyna Viktor M. Hrudnyskyi Vadym V. Dykyi Іvan V. Zihunov Volodymyr V. Zuiok Valerii A. Kirsanova Olha S. Kolodii Ihor V. Krаsnorutskyi Volodymyr S. Kushtym Anton V. Kushtym Yana O. Lehenkyi Yehor S. Romankov Viktor O. Rud Roman O. Slabospytska Olena O. Tretiakov Mykhailo V. Chernov Ihor O. Shevchenko Ihor V. popup.nrat_date 2024-12-24 Close