PSI - Issue 43

Sergiy Kotrechko et al. / Procedia Structural Integrity 43 (2023) 228–233 Author name / Structural Integrity Procedia 00 (2022) 000 – 000

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4. Conclusions 1. The dependence of the incompatibilities of microplastic deformations at grain boundaries or other interfacial boundaries on plastic strain and temperature is the main reason for the influence of these factors on the intensity of cleavage nuclei generation, which is a key factor controlling the slope of the temperature dependence and its scatter limits 2. Failure to take this effect into account in conventional models of local approach leads to errors in the prediction not only of the fracture toughness values but also of the fracture probability value. In the latter case, the underestimation of the fracture probability can be about 2-4 times. This error reaches a maximum at low fracture probabilities (lower threshold value for fracture toughness). This is of crucial importance for critical structural elements (RPVs, oil and gas pipelines, etc.). Acknowledgements This work was supported by the National Academy of Sciences of Ukraine (under grant number 0121U107569). 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