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Information × Registration Number 0224U001433, 0122U200379 , R & D reports Title Application of improved methods for assessment of current technical condition and metals damage of the reactor pressure vessels and other components of the NPP primary circuit in justifying the extension of their safe operation popup.stage_title Head Kharchenko Valerii V., Доктор технічних наук Registration Date 23-01-2024 Organization GS Pisarenko Institute of Strength Problems of the National Academy of Sciences of Ukraine popup.description2 Within the framework of this work, equipment has been modernized and a methodology has been developed for growing fatigue cracks and testing miniature compact 0.16T C(T) specimens and 0.5Т C(T) specimens with side-grooves for off-center tension to determine the fracture toughness characteristics of materials. According to the test results of a batch of specimens made of 15Kh2NMFA reactor steel in accordance with the developed techniques, the reference temperatures T0 were determined and the fracture toughness curves (Master curves) were constructed for all specimen types according to the ASTM 1921 standard. The obtained results showed that the deviation of the reference temperature values for different specimen’s types is no more than 4°C. Thus, subject to certain requirements, miniature 0.16T C(T) specimens and specimens with side grooves can be used to correctly determine the fracture toughness characteristics and assess the current state of materials of critical NPP equipment of the 1st circuit. Using the extended finite element method, numerical simulation of tests of compact CT-0.5T specimens, miniature CT-0.16T specimens and CT-0.5T specimens with side grooves were carry out. The fracture criteria parameters for 15Kh2NMFA steel were determined and the influence of specimen geometry and dimensions on the constraint at the crack tip and the features of crack propagation kinetics were investigated. The obtained results showed the effectiveness of using the extended finite element method to study the process of crack propagation in different types of samples. Based on the obtained experimental-computational research results, recommendations have been developed on the application of advanced techniques for assessing the current technical condition and damage of material of reactor pressure vessels and other 1st circuit NPP components when justifying the extension of their safe operation.  Product Description popup.authors Kondriakov Yevhen O. Kotliarenko Andrii A Kravchuk Andriy Vasylʹovych Kharchenko Valerii Volodymyrovych popup.nrat_date 2024-01-23 Close