Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia:
N. G. Kolbasnikov, Dr. Eng., Prof., Scientific and Educational Center "Research and Modeling of Materials", e-mail: nikolay.kolbasnikov@gmail.com
N. V. Zhukov, Leading Specialist, Scientific and Technical Complex "New Materials and Technologies", e-mail: zhukov_nv@spbstu.ru
S. A. Kuzin, Engineer of the laboratory "Research and modeling of the structure and properties of metallic materials", e-mail: kuzinsta@yandex.ru
V. S. Teteryatnikov, Engineer of the laboratory "Research and Modeling of the structure and properties of metallic materials", e-mail: vlad.teteryatnikov@rambler.ru

A study of the formation of austenite grain size during rolling of a thick strip on a continuous mill by simulating multi-stage rolling on a Gleeble complex has been performed. It is shown that at low degrees of deformation in the stands of the finishing group of a rolling mill, the formation of a different-grained austenite structure can occur due to selective grain growth without the formation of recrystallization nuclei, despite the precipitation of carbonitrides of microalloying elements. The value of the difference between the deformation strengthening of neighboring grains, sufficient for the grain boundary to overcome the retardation caused by the carbonitride particles, has been determined. It is possible to avoid this negative phenomenon by increasing the degree of deformation in each pass and ensuring the conditions for the formation of recrystallization nuclei. An example of a similar phenomenon observed when rolling beryllium is given.
The research was carried out with the financial support of the Ministry of Education and Science of Russia as part of the implementation of the program of the world-class Scientific Center in the direction of "Advanced Digital Technologies" of SPbPU (agreement dated April 20, 2022 No. 075-15-2022-311).

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