South Ural State University (National Research Uviversity), Chelyabinsk, Russia:
S. A. Botnikov, Cand. Eng., Doctoral Cand., Dept. of Materials Science and Physical Chemistry of Materials, e-mail: sbotnikov@bk.ru

The steel cleanliness is an important factor in its quality and the need for cleaner steels is growing every year. At present, there is no universal integrated approach to the development, implementation and stable operation of the technology for producing high-clean steel in the conditions of modern steelmaking production. An approach to the thermodynamic analysis of steelmaking processes has been developed, taking into account the complicated phenomenon of metal secondary oxidation, at all stages of the steel production. As the main scientific idea of the created SyTherMa (STM) software package, the position on the leading role of the oxidizing potential in the metal – slag – gas system and the control of the external supply of oxygen from the atmosphere, materials, slag and refractory effectively works. This idea provides a quick identification of critical points in developing and existing technologies, helps in determining effective ways to solve emerging quality problems of clean and ultra-clean steels. The proposed approach to the development of an efficient technology for the production of steel with a low content of non-metallic inclusions, taking into account all ongoing processes in a single technological chain melting – tapping – secondary metallurgy – casting, eliminates incorrect decisions on the cost of steel or the productivity of the melting shop. The performed analysis of a set of measures for the production of high-quality steels from smelting to casting made it possible to apply an integrated approach to the development of clean steel technology using all available modern technologies and tools.
Based on the proceedings of the XVII International Congress of Steelmakers and Metal Producers "From Ore to Steel" (April 03–07, 2023, Magnitogorsk).

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23. Botnikov S. А., Morov D. V. Method for production of super pure aluminum deoxidized steel for production of high-quality metal products. Patent RF, No. 2740949. Applied: 22.07.2019. Published: 21.01.2021.