Volgograd State Technical University, Volgograd, Russia
D. V. Rutskiy, Cand. Eng., Associate Prof., Head of Dept. of Materials Technology, e-mail: drutskii@vstu.ru
N. A. Zyuban, Dr. Eng., Prof., Dept. of Materials Technology
A. A. Shuklin, Postgraduate Student, Dept. of Materials Technology

JSC “Volzhsky Pipe Plant“, Volzhsky, Russia

A. N. Bozheskov, Chief Engineer, e-mail: vtz@vtz.ru

Currently, continuous casting is one of the main ways to obtain ingots for subsequent metallurgical processing in the conditions of modern metallurgical enterprises. At the same time, one of the main problems is the organization and maintenance of high sequence of the process, since one of the main technological parameters affecting the cost of production of continuously cast billets is the casting ability of steel in continuous casters. When mastering the production of continuously cast billets from stainless steel grades on existing steelmaking units, problems arise related to poor casting ability. It was found in this work that the reason for the low casting ability in production of stainless steels is the release of refractory oxide (TiO and Al₂O₃–TiO₂) and oxynitride (Al₂O₃–TiO₂ and TiN) inclusions in deposits on the walls of the steel filling tract. The research used optical and electron microscopy methods with an automatic particle analyzer (EDAX Partical/Phase Analysis Software). Identification of non-metallic inclusions in the samples taken at the stages of ladle treatment and casting showed that oxide inclusions (TiO and Al₂O₃–TiO₂), formed after the introduction of FeTi, before the second stage of vacuum processing, nitride (TiN) and oxynitride inclusions (Al₂O₃–TiO₂ and TiN), are formed during continuous casting and solidification of continuously cast billets. Based on the conducted research, measures are proposed aimed at preventing the formation of refractory non-metallic inclusions containing titanium, which made it possible to increase the sequence of casting on existing steelmaking units in the electric steelmaking shop. The increase in serial production to two melts per series led to a reduction in the consumption of the metal coefficient in the production of continuously cast billets by 20 kg/t, as well as to a reduction in the cost of tundish refractories.

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