Nizhniy Tagil Iron and Steel Works

Producing metal with low non-metallic inclusion contamination remains a pressing challenge for metallurgical engineers. One key area for improving steel refining technology is selecting optimal compositions of refining alloys to enhance secondary metallurgy efficiency. This study presents results from using cored wire containing alkaline earth metals (Ca, Ba) at large-scale steelmaking plants. The research highlights the mechanism of non-metallic inclusion removal when using alkaline earth metal complexes compared to conventional calcium-based materials. Notably, the SiCaBa modifier demonstrated significantly improved calcium yield stability, enabling more reliable prediction of residual calcium content in molten steel. This helps prevent calcium overmodification and reduces risks of additional non-metallic inclusion formation. Industrial trials of INSTEEL® cored wire under various production conditions showed consistent trends: reduced non-metallic inclusion contamination; increased calcium yield efficiency (29.9% at Ural Steel JSC, 14.6% at KSP Steel LLP, and 23.5% at EVRAZ NTMK JSC); improved cleanliness ratings: at Ural Steel JSC (17G1SU grade): Brittle silicate max score decreased from 4.0 to 2.5; non-deformable silicates from 4.0 to 3.0; at EVRAZ NTMK JSC (OS grade). Non-deformable silicate contamination reduced from 2.75 to 2.47; 12.9% reduction in refining treatment costs. The findings demonstrate that complex alkaline earth metal alloys offer measurable advantages in secondary metallurgy processing compared to standard calcium treatments

A finite element analysis of the stress-strain state of a steel ball stamping process from a cylindrical billet was performed under the conditions of a non-isothermal process in an axisymmetric formulation. Three options for stamping a ball from blanks with different height-to-diameter ratios are considered. Distribution of temperature, degree and deformation rate, average stress and stress intensity are given. It has been found that with an increase in the relative workpiece height, the degree of deformation over the ball volume increases. In this case, the temperature value in the ball volume increases. A metal cooldown zone on the periphery of billet ends was revealed. Stress state index assessment at the last stage of stamping made it possible to identify the workpiece dangerous zones from the point of failure. When considering the metal plasticity indicators, this makes it possible to predict the defectiveness of products.

This article discusses the methods for increasing the durability of the lining (increasing the number of fillings) of steel-pouring ladles without changing the technology of steel production. It is shown that under the conditions of NTMK, an increase in the durability of the lining is possible due to the strengthening of weak zones using new formats of refractory products while maintaining the working volume of this metallurgical unit. The use of a new lining layout made it possible to increase the durability of the lining by 5

The results of a comprehensive study of the material microstructure of refractory samples after service in the furnace of a blast furnace with a useful volume of 2200 m3 for 14 years are presented. Structural and genetic analysis established a characteristic sequence of processes of degeneration and wear of the ceramic furnace stack, including 6 stages: the formation of micro-and macro-cracks; condensation of vaporous zinc; zinc oxidation with the formation of fire-resistant ZnO zincite and the deposition of carbon black by the; chemical interaction of zinkite with mullite and corundum to form ZnAl2O4 ganite and 2ZnO·SiO2 willemite; partial oxidation of silicon carbide with the release of silica glass SiO2, eutectic melt of complex composition, and wellimite. Due to intensive accumulation of capillary pores, infiltration of the slag melt in the volume of refractories does not occur. Wear of refractories in the furnace has a complex, mainly thermochemical mechanism and a low speed due to the formation of a garnish containing refractory compounds. Ill. 5. Ref. 14.