Bauman Moscow State Technical University, Moscow, Russia:
I. S. Vasilyev, Leading Engineer, Research Institute of Structural Materials and Technological Processes (NII KM & TP)
P. Yu. Zhikharev, Leading Engineer, NII KM & TP, e-mail: zhikharev@bmstu.ru
A. V. Perestoronin, Cand. Eng., 2^nd category engineer of the Scientific and Educational Center "Center for Additive Technologies"

PJSC Magnitogorsk Iron and Steel Works, Magnitogorsk, Russia:
V. V. Mukhin, Cand. Eng., Leading Engineer of the Rolling Production Group of the Scientific and Technical Center

A description of the technique for developing the technology for hot-rolled coils manufacturing in the conditions of an existing production, the technology and characteristics of which go beyond the passport characteristics of the equipment, is presented. It is proposed to carry out comprehensive laboratory studies of the developed material (the kinetics of recrystallization processes during heating and rolling, the kinetics of structural transformations, material properties at production temperatures), engineering calculations of the equipment operation and simulation of the strip behavior during the rolling and coiling before the industrial testing of the hot rolled products manufacturing technology. The practical application of the proposed approach is demonstrated by the example of the development of a technology for manufacturing hot-rolled coils from low-carbon boron steel with a minimum yield strength of 1000 MPa. For the developed steel, rational temperature parameters for slabs heating are determined, which exclude the development of collective recrystallization and the formation of an uneven-grained structure, and also limiting deformation modes are defined, which ensure efficient grain refinement and implemented on existing hot strip mills. It has been established that in low-carbon steel a high strength with satisfactory ductility, low-temperature toughness, and the ability to cold forming (bending, profiling, etc.) is achieved due to the formation of a lower bainite structure in rolled products. The required structural state was obtained by applying the technology of interrupted quenching from rolling heating at massaverage cooling rates of about 25 °C/s.
The studies were carried out within the program of the Russian Federation of strategic academic leadership "Priority-2030" aimed at supporting the development programs of educational institutions of higher education, the scientific project PRIOR/SN/NU/22/SP5/26 "Development of innovative digital tools for the implementation of applied artificial intelligence and advanced statistical analysis of Big Data in production processes of metallurgical products".

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