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Steel Making
Название Improvement of the melting technology and ladle treatment of steels 15Х2НМФА (15Kh2NMFA) (A-A, class 1) for special critical duty components in nuclear power stations
DOI 10.17580/cisisr.2017.02.02
Автор V. A. Dub, S. V. Novikov, I. A. Shchepkin, O. Yu. Kornienko
Информация об авторе

National University of Science and Technology “MISiS” (Moscow, Russia)

V. A. Dub, Cand. Eng., Leading Expert, the Chair of Physical Chemistry

 

RF State Research Centre JSC SPA “CNIITMASH” (Moscow, Russia)
S. V. Novikov, Cand. Eng., Scientific Researcher, Electric Melting Lab.
I. A. Shchepkin, Dr. Eng., Leading Scientific Researcher, Electric Melting Lab.

 

Ural State Federal University n. a. the 1st RF President B. N. Eltsin (Ekaterinburg, Russia)
O. Yu. Kornienko, Cand. Eng., Associate Prof., the Chair of Heat Treatment and Metal Physics, o.j.kornienko@urfu.ru


A. P. Kulikov, V. A. Tsarev, V. A. Novikov and D. S. Tolstykh participated in this research.

Реферат

The ways of increase of the power engineering products resource for large-size critical components made of steel 15Kh2NMFA are described in terms of radiation and thermal brittleness criteria due to the content restriction of harmful and impurity elements, primarily phosphorus, sulfur and hydrogen. The steelmaking process for this steel grade includes smelting of liquid semiproduct in the electric arc furnace DSP-120, secondary refining process and ladle-vacuum treatment. The main technological task in melting of this semiproduct is obtaining of a final phosphorus content not more than 0.003% using deep dephosphorization process. For this purpose solid carburizers in the charge, such as pig iron and coke, are replaced by pulverized carbon-containing materials, blowing-in with oxygen or adding to slag during oxidizing period. In order to organize the process of deep desulfurization simultaneously with the removal of hydrogen, it is necessary to obtain the optimal slag composition in the required amount and high deoxidation of the metal before ladle vacuum treatment. Deep bulk deoxidation was carried out immediately during discharge of liquid semiproduct out of the electric arc furnace. Regulated content of the following elements was obtained as a result of usage of these methods: phosphorus 0.003–0.004%, sulfur 0.001–0.002%, hydrogen 0.8–1.1 ppm, oxygen activity 3–5 ppm.

The study was financially supported by Ministry of Education and Science of the Russian Federation within the scope of accomplishment of the Federal Targeted Program “Investigations and innovations on priority development directions of the RF scientific–technological complex for 2014–2020 (application code “2015–14–579–0173–366”). Agreement of subsidizing No. 14.578.21.0114 dated October 27. 2015. Unique identifier of applied scientific researches and experimental development (PNIER) — RFMEFI57815X0114.

Ключевые слова Heat-resistant steels, melting, liquid semiproduct, dephosphorization, desulfurization, deoxidation, vacuum treatment, charge materials
Библиографический список

1. Astafyev A. A., Markov S. I., Kark G. S. Lowering of ability of pearlite shell steel to grain boundary impurity embrittlement. Proc. of All–Union Scientific Conference “Modern problems of metal quality improvement”. Donetsk. 1978. pp. 91–92.
2. Kark G. S., Astafyev A. A., Markov S. I. Influence of joint equilibrium grain boundary segregation of phosphorus and nickel on embrittlement of low–alloyed steel during long–term isothermal holding. Proc. of IX All–Union Conference on physics of metal strength and ductility. Kuibyshev. 1979. pp. 215–216.
3. Kark G. S., Markov S. I. Reverse tempering brittleness of reactor shell steel. Proc. of All–Uniom Scientific Conference “Progressive technological processes in nuclear machine–building”. Moscow. Mashprom. 1981. pp. 54–56.
4. Kark G. S., Astafyev A. A. Tempering brittleness of low–alloyed Cr–Ni–Mo steels. Metal Science and Heat Treatment of Steels for Equipping of Power Engineering Stations. Proc. Of TsNIITMASH. 1983. 177 p.
5. Kark G. S. Investigation of reverse tempering brittleness of steels for nuclear reactors shells. Dissertation … of Candidate of Engineering Sciences. Moscow. TsNIITMASH. 1980. 150 p.
6. Astafyev A. A., Markov S. I., Kark G. S. Influence of chemical composition of pearlite steels on their radiation embrittlement. Proc. of Scientific Seminar “Radiation Physics of Metals and Alloys”. Tbilisi. 1976. pp. 213–224.
7. Yoo К.–В., Kim J.–H. Effects of impurity segregation to grain boundary on intergranular cracking in 2.25Cr–l W steel. Procedia Engineering. 2011. Vol. 10., pp. 2484–2489.
8. Khodan A. N. et al. Mechanism and kinetics of phosphorus segregation at the grain boundaries of VVER–1000 pressure vessel steel at 280 – 320 °C. Acta Materialia. 2013. 10 p.
9. Lunev V. V., Averin V. V. Sulfur and phosphorus in steel. Мoscow : Metallurgiya. 1988. 256 p.
10. Sang Gyu Park, Min–Chul Kim, Bong Sang Lee, Dang Moon Wee. Effects of the P and Mn on Temper Embrittlement in SA508 Gr. 4N Low Alloy Steel. Transactions of the Korean Nuclear Society. Autumn Meeting. Korea, PyeongChang. 2008. October 30–31.
11. Oiks G. N. Steel production. Мoscow : Metallurgiya. 1973. 816 p.
12. Dyachenko V. F., Sarychev A. F., Velikiy A. B., Nikolaev O. A., Ivin Yu. A., Valiakhmetov A. Kh. Technological features of steel making in 180 t arc furnaces at Magnitogorsk Iron and Steel Works. Elektrometallurgiya. 2008. No. 2. pp. 9–10.
13. Bigeev V. A., Malofeev A. E., Panteleev A. V., Nikolaev O. A., Ivin Yu. A. Features of slag processes in the modern electric arc furnace. Chernaya Metallurgiya. Bulleten NTI. 2009. No. 10. pp. 48–50.
14. Chichko A. A., Matochkin V. A., Sobolev V. F., Chichko A. N. Management of steel dephosphorization process during melting of semiproducts in electric arc furnace. Elektrometallurgiya. 2008. No. 9. pp. 27–32.
15. Novikov V. A., Kulikov A. P., Shchepkin I. A., Afanasyev S. Yu. Batov Yu. M. Hydrogen removal during steel refining and vacuum treatment in the ladle. Elektrometallurgiya. 2012. No. 7. pp. 17–19.
16. Sommervill I. Measurement, forecast and application of volumes of metallurgical slags. Injection Metallurgy 86. Мoscow: Metallurgiya. 1990. pp. 107–120.
17. Dub V. S. To research, develop and put onto practice the technology of deep desulfurization and dephosphorization of structural steels applying to the conditions of “Izhorsky zavod”. TsNIITMASH Report. 1985. 42 p.
18. Kawakami K., Kikuchi Y., Kavai Y., Tate M. Steel desulfurization in a ladle via the method of Nippon Kokan. Chernye metally. 1982. No. 5. pp. 31–36.
19. Novikov V. A., Iodkovsky S. A., Dub V. S., Ignatyev V. I., Durynin V. A. Lowering of content of sulfur and hydrogen via ladle treatment of alloyed steel. Stal. 1987. No. 7. pp. 26–30.
20. Novikov V. A., Tsarev V. A., Novikov S. V., Afanasyev S. Yu. Batov Yu. M. Thermodynamic and kinetic features of desulfurization process. Elektrometallurgiya. 2012. No. 9. pp. 16–20.

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