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Rolling and other Metal Forming Processes
ArticleName Features of formation of fine-dispersed structure of coil rolled bearing steel
DOI 10.17580/chm.2024.04.05
ArticleAuthor S. A. Savchenko, I. A. Kovaleva, I. V. Astapenko, A. B. Sychkov

Belarusian Steel Works — the management company of the BMC holding, Zhlobin, Belarus

S. A. Savchenko, Leading Engineer-Technologist of the Technical Management of the Rolling Dept., e-mail:
I. A. Kovaleva, Head of the Research Center`s Research Lab. – the Branch Lab. of Metallurgical and Steel Wire Production Technologies of the Technical Dept., e-mail:


Sukhoi State Technical University of Gomel, Gomel, Belarus
I. V. Astapenko, Dr. Agr., Associate Prof., Dept. of Metallurgy and Materials Processing Technology, e-mail:


Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia
A. B. Sychkov, Dr. Eng., Prof., Dept. of Foundry Processes and Materials Science3, e-mail:


To ensure quality characteristics of coiled products required by customers after spheroidizing annealing in terms of mechanical properties, microstructure and depth of decarbonized layer (hereinafter referred to as DCL) of ShKh15 steel, production and research technological measures were carried out on rolling mill 370/150 with different conditions of initial temperature and dynamics of cooling of the wire rod. The article contains the results of research and analysis to determine effective initial microstructure of hot-rolled bearing round steel in coils with diameter of 6.5 mm, subjected to subsequent spheroidizing annealing, improving quality of rolled products by improving technological modes of in-line two-stage cooling of wire rod at air cooling stage. Dependence of influence of initial temperature and dynamics of air cooling process on formation of interlamellar distance of pearlite in the primary microstructure of coiled steel has been studied. Influence of austenitization temperature on dispersion of pearlite in bearing steel is described. Effective mode of in-line air cooling of bearing steel wire rod for subsequent spheroidizing annealing has been determined, providing uniform fine pearlite structure along the entire length of the wire rod coil, without presence of quenching structural inclusions. It has been established that initial coarse-lamellar form of pearlite on the surface of coiled steel according to the basic mode of in-line heat treatment in hot-rolling line of wire rod of mill 370/150 (initial cooling with water to temperature of 870-910 °C in the area of coil former and subsequent slow cooling with air on roller conveyor by the first four fans with air supply power of 10%) leads to excessive values of DCL depth and incomplete spheroidization after annealing of coils.

keywords Hot rolling, bearing steel, initial microstructure, decarbonized layer, two-stage cooling, dynamic recrystallization, thermokinetic decomposition of austenite, spheroidizing annealing, pearlite dispersion

1. Voinov S. G., Shalimov A. G. Ball bearing steel. Moscow : GNTI, 1962. 480 p.
2. Zinchenko S. A., Ibragimov A. U. Thermocyclic spheroidizing annealing of bearing steel. Modern instrumental systems, information technologies and innovations: Collection of Proceedings of the XII International Scientific and Practical Conference: in 4 volumes, Kursk, March 19–20, 2015. Vol. 2. Kursk : Universitetskaya kniga. 2015. pp. 144–147.
3. Spector A. G., Zelbert B. M., Kiseleva S. A. Structure and properties of bearing steels. Moscow : Metallurgiya. 1980. 264 p.
4. Novikov I. I. Theory of heat treatment of metals. Moscow : Metallurgiya. 1978. 392 p.
5. Bhadeshia H. K. D. H. Steels for bearings. Progress in materials Science. 2012. Vol. 57, Iss. 2. pp. 268–435.
6. Rauzin Y. R. Thermal treatment of chromium steel (for bearings and tools), 3rd ed., revised and additional. Moscow : Mashgiz. 1963. 378 p.
7. Hwang H., De Cooman B. C. Influence of the initial microstructure on the spheroidization of SAE 52100 bearing steel. Steel Research International. 2016. Vol. 87, Iss. 1. pp. 112–125. DOI: 10.1002/srin.201400591
8. Czarski A., Skowronek T., Matusiewicz P. Stability of a lamellar structure – Effect of the true interlamellar spacing on the durability of a pearlite colony. Arch. Metall. Mater. 2015. Vol. 60. pp. 2499–2504. DOI: 10.1515/amm-2015-0405
9. Svishchenko V. V., Ivanaisky A. A. Influence of initial structure on result of spheroidizing annealing of structural steel. Polzunovskiy vestnik. 2015. No. 1. pp. 61–63.
10. Huo X. D. et al. Effect of spheroidizing annealing time on microstructure and hardness of GCr15 bearing steel. Advanced Materials Research. 2012. Vol. 581. pp. 928–931. DOI: 10.4028/
11. Zhao X.-Yu., Zhao X.-M., Dong C., Yang Y., Han H. Effect of prior microstructures on cementite dissolution behavior during subcritical annealing of high carbon steels. Metals and Materials International. 2022. Vol. 28, Iss. 6. pp. 1315–1327. DOI: 10.1007/s12540-021-00983-y
12. Savchenko S. A., Kovaleva I. A., Guzova I. A., Sychkov A. B. The influence of initial structure of coil rolled bearing steel on uniformity of obtained structure after spheroidizing annealing. Chernaya metallurgiya. Byulleten nauchno-tekhnicheskoy i ekonomicheskoy informatsii. 2023. Vol. 79, No. 3. pp. 251–260. DOI: 10.32339/0135-5910-2023-3-251-260
13. Savchenko S. A., Kovaleva I. A., Guzova I. A., Sychkov A. B. The influence of structure of a coil rolled bearing steel on its structure and surface decarburization after spheroidizing annealing. Tekhnologii metallurgii, mashinostroeniya i materialoobrabotki. 2022. No. 21. pp. 133–144.
14. Puteev V. S., Savchenko S. A., Pankovets I. A., Voznaya V. I., Astapenko I. V. Improvement of the technological process of bearing steel production on the 370/150 mill. Lityo i metallurgiya. 2021. No. 3. pp. 65–73. DOI: 10.21122/1683-6065-2021-3-65-73
15. Pankovets I. A., Savchenko S. A., Voznaya V. I. et al. Investigation of factors contributing to the reduction of carbide inhomogeneity in bearing steel. Chernaya metallurgiya. Byulleten nauchno-tekhnicheskoy i ekonomicheskoy informatsii. 2021. Vol. 77. No. 7. pp. 804–810. DOI: 10.32339/0135-5910-2021-7-804-810
16. GOST 801–2022. Rolled products from bearing steel. Specifications. Introduced: 01.08.2023.
17. Huang Z. Y., Du L. X., Li M. Z. et al. Study on rolling and hot delivery spheroidizing annealing of GCr15 bearing steel. J. of Mater. Eng. and Perform. 2023. Vol. 32. pp. 7779–7784. DOI: 10.1007/s11665-022-07656-w
18. Li Z. X., Li C. S., Ren J. Y. et al. Design of online spheroidization process for 1.0C-1.5Cr bearing steel and microstructure analysis. Metall. Mater. Trans. A. 2018. Vol. 49. pp. 1782–1794. DOI: 10.1007/s11661-018-4511-9
19. Li Z. X., Li C. S., Zhang J. et al. Effects of annealing on carbides size and distribution and cold formability of 1.0C-1.5Cr bearing steel. Metall. Mater. Trans. A. 2015. Vol. 46. pp. 3220–3231. DOI: 10.1007/s11661-015-2904-6
20. Smirnov M. A., Schastlyvtsev V. M., Zhuravlev L. G. Basics of thermal treatment of steel. Moscow : Nauka i tekhnologii, 2002. 519 p.
21. Yatsenko Yu. V., Emchenko B. C., Reus V. A., Likhov V. K. Quality of bearing steel wire rod after two-stage cooling. Stal. 1985. No. 6. pp. 62–63.

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