Volgograd State Technical University (Volgograd, Russia):

M. Yu. Chubukov, Post-graduate
D. V. Rutskiy, Cand. Eng., Associate Prof.
N. A. Zyuban, Dr. Eng., Prof., Head of the Chair “Technology of Materials”, e-mail: tecmat@vstu.ru
M. V. Kirilichev, Post-graduate

The research of the structure of continuous-cast billets made of preperitectic and peritectic steel classes with different content of alloying elements is presented. Differences in the structure and development of structural zones are shown. It has been shown that the pre-peritectic class 06ГФБА steel has the greatest intensive heat removal zone (1.5–2.0 times) length, while the size of the crystals it consists of is minimal and does not exceed 10 mm. As the grade carbon content in steel increases, the parameters under consideration change. For 13ГФА steel (C = 0.14%), the length of intensive heat removal zone is reduced and does not exceed 17 mm, thus the crystallite size increases to 30 mm. The density of the dendritic axes is maximum for 06ГФБА steel and minimum for 13 ГФА steel. The greater development of intensive heat removal zone leads to a more uniform and, accordingly, favorable distribution of non-metallic inclusions, over the cross section of continuously cast billets from steel 06ГФБА. The absence of peritectic transformation during hardening, a decrease in the hardening interval, an increase in the development of zones of intensive heat removal favorably affect a decrease in the degree of segregation and, consequently, contributes to obtaining a continuously cast billet with a uniform distribution of chemical elements and lower segregation level.
This work has been supported by the Russian Foundation for Basic Research, project No. 18-08-00050

1. Safronov А. А., Tazetdinov V. I., Torokhov G. V. Mastering the production of continuously cast billets with a diameter of 550 mm from pipe steel grades at the caster No. 2 of the Iron Ozone 32 electric steel complex. Stal. 2013. No. 10. pp. 58–62.
2. Safronov А. А. et. al. Investigation of metal`s chemical heterogeneity of the continuously cast billet of a diameters 460 and 550 mm produced at the Iron Ozone 32 electric steel complex. Stal. 2013. No. 8. pp. 18–22.
3. Dyudkin D. A., Kisilenko V. V., Smirnov A. N. Production of steel. Vol. 4: Continuous casting of metal. Moscow: Teplotekhnik, 2009. 528 p.
4. Sanghyeon Lee. State of the Art Technology in Slab Continuous Casting: A Casting Speed Point of View in POSCO. BHM Berg- und Hüttenmännische Monatshefte. January 2018. Vol. 163, Iss. 1. pp. 3–10.
5. Available at: www.danieli.com/en/products/products-processesand-technologies/bloom-casters_26_88.htm
6. Kittaka S., Kaniki T., Watanabe K., Miura Y. Multi-Mode EMS for Slab Casters – Recent Improvements and New Applications. Nippon Steel Technical Report. July 2002. Vol. 86. pp. 68–73.
7. Kubota J., Kubo N., Ishii T. Steel flow control with travelling magnetic field for slab continuous caster mold. Tetsu-to Hagane. 2000. Vol. 86, No. 4. pp. 271–277.
8. Chowaniec F., Stanick M. The comparison of roundand square billets casting from peritectic steel grades. 2^nd International Metallurgical Conference, Trinec. 1997. pp. 139–143.
9. Nosochenko O. V., Isaev O. B., Lepikhov A. S., Dektyarev P. А. et. al. Reduction of the axial segregation of elements in a continuously cast billet during introduction of a steel tape. Stal. 2003. No. 9. pp. 42–44.
10. Bely А. P. Central segregation heterogeneity in continuously cast sheet blanks and thick plates. Moscow: Metallurgizdat, 2005. 136 p.
11. Dub V. S., Safronov A. A., Movchan M. A. et al. The influence of a secondary treatment technology on types of non-metallic inclusions formed and corrosion resistance of steel. Elektrometallurgiya. 2016. No. 5. pp. 3–15.
12. Fandrich R., Luengen H. B., Wuppermann K. D. Ladle metallurgy in Germany: the state and main lines of research. Chernye Metally. 2008. No. 7. pp. 26–34.
13. Millman S. Ladle operations. IISI study on clean steel. Belgien: Brussel: Intern. Iron and Steel Institute, 2004. pp. 61–74.
14. Grigorovich K. V., Garber А. К. Analysis of the processes of carbon steels secondary treatment. Perspektivnye materialy. 2011. No. 13. pp. 13–25.
15. Shakhpazov E. Kh., Zaytsev А. I., Shaposhnikov N. G., Rodionova I. G., Rybkin N. А. On the issue of physical and chemical prediction of the non-metallic inclusions type. Complex deoxidation of steel with aluminum and calcium. Metally. 2006. No. 2. pp. 3–13.
16. Agbola О. F., Morozova Т. V., Dub А. V. Non-metallic inclusions in low-alloyed tube steel. Metallurg. 2005. No. 4. pp. 67–73.
17. Efron L. I. Metal science in great metallurgy. Tube steels. Moscow: Мetallurgizdat, 2012. 696 p.
18. Zhulyev S. I., Zyuban N. А., Rutsky D. V. Steel ingots, quality issues and new technologies: Monograph. Volgograd: VolgGTU, 2016. 179 p.
19. Dub V. S., Romashkin А. N., Malginov А. N., Ivanov I. А., Tolstykh D. S. The study of influence of a forge ingots configuration on the chemical elements distribution across their cross section. Problemy chernoy metallurgii i materialovedeniya. 2014. No. 1. pp. 5–19.
20. Kazakov А. А., Zhiteneva А. I., Salynova М. А. Estimation of single large nonmetallic inclusions in steel using statistics of extreme values. Chernye Metally. 2018. No. 11. pp. 70–74.
21. Kazakov А. А., Kovalev P. V., Ryaboshuk S. V., Zhironkin М. V., Krasnov А. V. Control of nonmetallic inclusions formation during converter steel production. Chernye Metally. 2014. No. 14. pp. 91–96.
22. Kazakov A. A., Kovalev P. V., Ryaboshuk S. V., Mileykovsky A. B., Malakhov N. V. A study of temperature-time nature of nonmetallic inclusions to improve metallurgical quality of high-strength tube steels. Chernye Metally. 2009. No. 12. pp. 5–11.
23. Romashkin A. N., Dub V. S., Tolstykh D. S., Ivanov I. A., Malginov А. N. Criteria for assessing the susceptibility of steel to segregation in forging ingots. Metallurg. 2017. No. 10. pp. 35–40.
24. Banks K. M., Tuling A., Mintz B. Influence of V and Ti on hot ductility of Nb containing steels of peritectic C contents. Materials Science and Technology. 2011. Vol. 27, No. 8. pp. 1309–1314.
25. Banks K. M., Tuling A., Mintz B. Influence of chemistry on transverse cracking during continuous casting of medium C high N steel billets. Materials Science and Technology. 2012. Vol. 28. No. 11. pp. 1254–1260.
26. Semenov V. I., Nazaratin V. V., Andreev V. V., Nuraliev F. А. The influence of peritectic transformation on the crystallization, structure and properties of steel castings. Stal. 2016. No. 11. pp. 58–64.
27. Guyot V., Martin J. F., Ruelle A. et al. Control of surface Quality of 0,08% < C < 0,12 % Steel Slabs in Continuous Casting. ISIJ International. 1996. Vol. 36. pp. S227–S230.
28. Fedosov А. V., Skrebtsov А. М., Pashuk D. V. Transverse surface cracking during continuous casting of peritectic steels. Chernaya metallurgiya. Byulleten nauchno-tekhnicheskoi I ekonomicheskoi informatsii. 2018. No. 1. pp. 45–53.
29. Brune T. Senk D., Walpot R., Steenken B. Hot Ductility Behavior of Boron Containing Microalloyed Steels with Varying Manganese Contents. Metallurgical and materials transactions. June 2015. Vol. 46B. pp. 1405–1408.
30. Trutnev N. V., Lokhanov D. V., Chubukov M. Yu., Uskov D. P., Myakotina I. V. et al. Corrosion-resistant pipe from low-carbon pre-peritectic steel for oil and gas pipelines and method for its manufacture. Patent RF No. 2 647 201. Applied: 10.05.2017. Published: 14.03.2018. Bulletin No. 8.
31. Buzinov E. I., Rutsky D. V., Mozgovoy A. V., Zyuban N. A., Shelukhina Yu. M. Certificate of the state computer program registration No. 2010614950 dated 29 July 2010. RF. Metallographic program. GOU VPO VolgGTU. 2010.
32. GOST R 54153-2010. Steel. Method of atomic emission spectral analysis. Introduced: 01.01.2012.
33. GOST 1778-70 (ISO 4967-79) Steel. Metallographic methods for the determination on nonmetallic inclusions. Introduced: 01.01.1972.
34. Efimov V. А. Casting and crystallization of steel. Moscow: Metallurgiya, 1976. 552 p.
35. Efimov V. A., Eldarkhanov А. S. Technologies of modern metallurgy. Moscow: Novye tekhnologii, 2004. 784 p.