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Information × Registration Number 0223U005132, 0121U108779 , R & D reports Title The investigation of the structural state influence on the microstructural evolution optimization and increase of structural materials radiation resistance of the modern and future nuclear energy popup.stage_title Head Voievodin Viktor M., Доктор фізико-математичних наук Registration Date 15-12-2023 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description2 It has been experimentally shown that local corrosion of structural materials determines the performance of equipment elements. In the circulation circuits of NPP power units, uniform corrosion of structural materials leads to pollution of the medium of the second circuit, which affects the formation of local corrosion zones. In the second circuit of power units, in most cases, at least at the initial stage, local corrosion undergoes an electrochemical stage, accompanied by a violation of the passive state of the metal. In particular, this concerns steels 08Х18Н10Т and 10ГН2МФА, from which the heat exchange pipes and the collector of steam generators are made, respectively. The development of corrosion processes after the first stage depends on the composition, defective structure, properties and operating conditions. Internal stresses lead to the formation of corrosion cracks, vibrational loads - to the formation of fatigue cracks. One of the possible initiators of damage to heat exchange pipes is the inclusion of titanium carbide in the 08X18N10T steel. It is shown that in the process of operation, structural materials change their mechanical properties, which is associated with both corrosion and aging. With the growth of corrosion ulcers and cracks during corrosion damage of 08X18N10T steel, the strength and yield limits and the relative elongation of the metal localized around the defects decrease. When aging steel 10ГН2МФА in the first 100-200 thousand. hours (depending on the size of the grain) of the operation is strengthened, then its strength decreases. It was established that steel embrittlement was not observed. The change in properties is due to the redistribution of carbon in the grain with the appearance of carbide inclusions along the grain boundaries. It is determined that inclusions in structural materials of the nuclear power industry can contribute to the spread of corrosion in the depth of the metal. In particular, this applies to chain inclusi  Product Description popup.authors Gozhenko Sergiy V. Krainiuk Yevhen O Tolstolutska Galyna D. popup.nrat_date 2023-12-15 Close