Special Features of Transformations of Supercooled Austenite in Modern Structural Steels

Dilatometric, metallographic and durometric studies of transformations of supercooled austenite in modern commercial and experimental alloy steels under continuous cooling from the austenitization temperature at constant rates of 0.1 – 30 K/sec are performed. Thermokinetic diagrams of transformation of supercooled austenite are plotted and analyzed. The effect of alloying on the temperature and time intervals of formation of structural components in the steels is determined. Statistical analysis of the data obtained is performed to find the dependences of the critical temperatures Ac1 and Ac3 and of the critical quenching rate on the chemical composition of the steel. The behavior of the hardness of the formed structure as a function of the cooling rate is determined. Equations relating the coefficients of the function of logarithmic hardness and the chemical composition of the steels are suggested.

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Correspondence to M. V. Maisuradze.

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Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 29 – 38, July, 2020.

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Maisuradze, M.V., Ryzhkov, M.A., Antakov, E.V. et al. Special Features of Transformations of Supercooled Austenite in Modern Structural Steels. Met Sci Heat Treat 62, 448–456 (2020). https://doi.org/10.1007/s11041-020-00583-4

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Key words

  • steel
  • hardness
  • thermokinetic diagram
  • chemical composition
  • cooling rate