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.
Similar content being viewed by others
References
R. Chen, Z. Zheng, N. Li, and F. Feng, “In-situ investigation of phase transformation behaviors of 300M steel in continuous cooling process,” Mater. Charact., 144, 400 – 410 (2018).
M. Gomez, L. Rancel, E. Escudero, and S. F. Medina, “Phase transformation under continuous cooling conditions in medium carbon microalloyed steels,” J. Mater. Sci. Technol., 30(5), 511 – 516 (2014).
M. V. Maisuradze, M. A. Ryzhkov, and O. A. Surnaeva, “Transformations of supercooled austenite in promising high-hardenability machine steels,” Metal. Sci. Heat Treat., 60(5–6), 339–347 (2018).
L. E. Popova and A. A. Popov, Diagrams of Austenite Transformation in Steels and of Beta-Solution in Titanium Alloys [in Russian], Metallurgiya, Moscow (1991), 503 p.
M. Atkins, Atlas of Continuous Cooling Transformation Diagrams for Engineering Steels, British Steel Corporation, UK (1980), 260 p.
G. F. Vander Voort, Atlas of Time-Temperature Diagrams for Irons and Steels, ASM Int., USA (1991), 804 p.
M. V. Maisuradze, M. A. Ryzhkov, and A. A. Kuklina, “Phase transformations in D6AC steel during continuous cooling,” Solid State Phenom., 265, 712 – 716 (2017).
T. A. Kop, J. Sietsma, and S. Van Der Zwaag, “Dilatometric analysis of phase transformations in hypo-eutectoid steels,” J. Mater. Sci., 36, 519 – 526 (2001).
M. V. Maisuradze, M. A. Ryzhkov, Yu. V. Yudin, and A. A. Kuklina, “Transformations of supercooled austenite in a promising high-strength steel grade under continuous cooling conditions,” Metal. Sci. Heat Treat., 59(7–8), 486–490 (2017).
K. W. Andrews, “Empirical formulae for the calculation of some transformation temperatures,” J. Iron Steel Inst., 203(7), 721 – 727 (1965).
R. A. Grange, “Estimating critical ranges in heat treatment of steels,” Metal Progr., 70, 73 – 75 (1961).
J. Trzaska and L. A. Dobrzanski, “Modelling of CCT diagrams for engineering and constructional steels,” J. Mater. Proc. Technol., 192 – 193, 504 – 510 (2007).
M. A. Smirnov, V. M. Schastlivtsev, and L. G. Zhuravlev, Fundamentals of Heat Treatment of Steel [in Russian], UrO RAN, Ekaterinburg (1999), 496 p.
J. Datsko, L. Hartwig, and B. McClory, “On the tensile strength and hardness relation for metals,” J. Mater. Eng. Perform., 10(6), 718 – 722 (2001).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 29 – 38, July, 2020.
Rights and permissions
About this article
Cite this article
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
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11041-020-00583-4