DOI: 10.52150/2522-9117-2025-39-04

D. O. Stepanenko¹, Ph. D. (Tech.), Senior Researcher, ORCID 0000-0001-5913-2284
A. I. Belkova^1,*, Ph. D. (Tech.), Senior Researcher, ORCID 0000-0001-8519-9351
D. M. Togobitskaya¹, D. Sc. (Tech.), Professor, Leading Researcher, ORCID 0000-0001-6413-4823
L. O. Lisova¹, Ph. D. (Tech.), Senior Researcher, ORCID 0000-0001-6298-9115
S. V. Grekov¹, Researcher, ORCID 0000-0003-2849-0999

¹ Iron and Steel Institute of Z. I. Nekrasov National Academy of Sciences of Ukraine, Academican Starodubova Square, 1, Dnipro, 49107, Ukraine

^* Corresponding author: alla2904b8@gmail.com

INFLUENCE OF Cr₂O₃ CONTENT ON THE PROPERTIES OF SLAG MELTS OF THE CaO-SiO₂-Al₂O₃-MgO-FeO/Fe₂O₃-MnO SYSTEMS

Abstract. In the smelting of ferrochromium steels, slag formation processes play a key role, determining metal refining and chromium retention. Slags of the CaO–SiO₂–Al₂O₃–MgO–FeO/Fe₂O₃–MnO system are widely used due to their controllable physicochemical properties, however, the presence of chromium oxide Cr₂O significantly affects their structure and properties, which in turn determines the distribution of elements between phases and the degree of chromium loss. Analysis of open literature publications indicates a complex relationship between the Cr2O3 content and slag viscosity, which depends on various indicators of a specific slag system and the metal smelting process. Its amphoteric nature causes a double effect: at low concentrations it reduces viscosity, at high concentrations it increases it, and also promotes the formation of solid phases, which additionally increase it. Data on electrical conductivity are contradictory, which indicates the need for targeted research. For accurate analysis and prediction of behavior, the analyzed multicomponent slag system, which includes oxides CaO, SiO₂, Al₂O₃, MgO, FeO, MnO and Cr₂O₃, is extremely complex. Each oxide has a specific and interconnected effect on the structure and properties of the slag, especially on viscosity. The effect of components, including Cr₂O₃, should be considered in the context of synergistic or antagonistic interactions with other components. For the development of predictive models, certain opportunities are provided by the integral parameters of the oxide system model from the position of the concept of directional chemical bonding, which allow comprehensively taking into account the effect of the entire component composition of the slag system on its properties. A high level of viscosity correlation with the indicators of the chemical equivalent of the slag composition ∆e and chemical individuality tgα has been established, and it has been shown that slags, different in technological purpose, are identified by specific values of the parameter ∆e. The conducted studies confirm the feasibility and effectiveness of using integral parameters of the oxide system composition for predicting and evaluating the properties of chromium-containing slags in order to optimize slag-forming mixtures and increase the efficiency of smelting ferrochromium steels.

Key words: ferrochromium steel, slag, chromium oxide Cr₂O₃, viscosity, electrical conductivity, parameters of interatomic interaction in melts, predictive models.

For citation: Stepanenko, D. O., Belkova, A. I., Togobitskaya, D. M., Lisova, L. O., & Grekov, S. V. (2025). Influence of CR₂O₃ content on the properties of slag melts of the CaO-SiO₂-Al₂O₃-MgO-FeO/Fe₂O₃-MnO systems. Fundamental and applied problems of ferrous metallurgy, 39, 61-77. https://doi.org/10.52150/2522-9117-2025-39-04

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Received  10.07.2025
Accepted 21.10.2025
Published online 01.12.2025