The contribution of separations into the impact toughness of steels of strength class X80 is studied. Tests for impact bending are preformed in the range from +20 to –90°C, and analysis of fracture surfaces of Charpy specimens is performed. It is shown that the length L h of the high-energy zone of homogeneous ductile fracture is directly correlated with the level of the impact toughness KCV. The evolution of the form and number of separations upon lowering of the test temperature is considered. The conditions of attainment of a high level of impact toughness (KCV – 60 ≥ 250 J/cm2) are determined.
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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 39 – 44, August, 2015.
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Farber, V.M., Khotinov, V.A., Morozova, A.N. et al. Separations and Their Contribution into the Impact Toughness of Steels of Strength Class K65 (X80). Met Sci Heat Treat 57, 487–491 (2015). https://doi.org/10.1007/s11041-015-9909-z
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DOI: https://doi.org/10.1007/s11041-015-9909-z