DOI: 10.52150/2522-9117-2024-38-588-601

Zotov Dmytro Serhiiyovich, Ph. D. (Tech.), Head of quality department, PJSC “UKRNAFTA”, Nestorivskiy prov. 3-5, Kyiv, 04053, Ukraine. ORCID: 0009-0007-2996-0709. E-mail: dmitry.zotov@gmail.com

Niziaiev Kostiantyn Heorhiiovych, D. Sc. (Tech.), Professor, Ukrainian State University of Science and Technologies, Lazariana Str., 2, Dnipro, 49010б Ukraine. ORCID: 0000-0002-9260-0964. E-mail: metsteel.dmeti@gmail.com

Uzlov Oleg Volodymyrovych, Ph. D. (Tech.), Associate professor, Senior researcher, Iron and Steel Institute of Z. I. Nekrasov National Academy of Sciences of Ukraine, Academican Starodubova Square, 1, Dnipro, 49107, Ukraine. ORCID: 0000-0003-1329-5576. Email: oleg.uzlov@gmail.com

Puchykov Oleksandr Volodymyrovych, Senior researcher, Iron and Steel Institute of Z. I. Nekrasov National Academy of Sciences of Ukraine, Academican Starodubova Square, 1, Dnipro, 49107, Ukraine. ORCID: 0000-0003-4119-6399. Email: alexandr.Puchikov@gmail.com

Shpak Olena Adolfivna, Junior Researcher, Iron and Steel Institute of Z. I. Nekrasov National Academy of Sciences of Ukraine, Academican Starodubova Square, 1, Dnipro, 49107, Ukraine. Email: okc.testcenter@ukr.net

REDUCTION OF THE CONTENT AND SIZE OF NON-METALLIC INCLUSIONS IN STRIP ROLLED LOW CARBON STEEL

Abstract. Reducing the number of non-metallic inclusions in finished rolled products during smelting and processing of high-quality steel is an urgent problem for all global metallurgical enterprises. Results of low carbon steel quality improvement by non-metallic inclusions cleaness parameters at Ukrainian steel plant are shown. Deoxidation of semi-product with large quantity of aluminium during tapping leads to formation of vast variety of oxide inclusions. Bigger ones coagulate and assimilate into slag. Smaller inclusions of herzenite, mulit and magnesium spinel usually stay in liquid steel. Complete elimination of smaller non-metallic inclusions during ladle furnace treatment is rather difficult. In order to decrease size and quantity of alumina and silicate non-metallic inclusions one should provide oppression of these complex inclusions formation during steel tapping from converter to the ladle. This could be achieved by creating thermodynamical conditions for complete transfer of non-metallic inclusions into slag. Another way is to change aluminium for alternative deoxidisers which do not pollute steel. Steel deoxidation with help of calcium or carbon may allow to decrease quantity of alumina non-metallic inclusions drastically because of positive effect on their solubility in liquid steel as well as redundant oxygen removal as a gas in CO and CO₂ compounds. Effect of calcium carbide preliminary deoxidation during pouring of the semi-finished product from the oxygen converter on the content of non-metallic inclusions in flat rolled product has been analyzed. Non-metallic inclusions severity level number has been made according to DSTU 8966:2019. Technology of steel deoxidation during converter tapping has been improved. It has been shown that the partial replacement of aluminium with calcium carbide during deoxidation of steel at the final stage of smelting allows to reduce content of non-metallic inclusions in low-carbon flat rolled strip product.

Key words: calcium carbide, strip rolled product, non-metallic inclusions, low-carbon steel.

DOI: https://doi.org/10.52150/2522-9117-2024-38-588-601

For citation: Zotov, D. S., Niziaiev, K. H., Uzlov, O. V., Puchykov, O. V., & Shpak, O. A. (2024). Reduction of the content and size of non-metallic inclusions in strip rolled low carbon steel. Fundamental and applied problems of ferrous metallurgy, 38, 588-601. https://doi.org/10.52150/2522-9117-2024-38-588-601

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