Longitudinal rolling in calibers is one of the main technologies for obtaining long metal products. At the same time, during traditional rolling in calibers in the finished rolled products the remains of the cast structure and heterogeneity of the mechanical properties of the metal across the cross-section are observed. These disadvantages can be eliminated by implementing severe plastic deformation (SPD) in the volume of the metal. However, the low manufacturability of most SPD technologies constrains their use in industry. Therefore, the development and research of a new way to implement SPD in a continuous technological process, in particular during rolling in continuous mills, is an urgent scientific and technological problem. The project proposes to develop new technological schemes of rolling rolls calibration, providing the implementation of intense shear deformation. According to the hypothesis proposed in the project non-monotonic nature of the metal flow during rolling in the new system of gauges will lead to a deep densification and elaboration of the metal structure at all levels of the metallophysical structure, which contributes to an integrated improvement in the mechanical and service properties of metal products. Establishment of regularities of formation of metal structure and properties under these conditions is the main scientific issue of the project. The results obtained affect the development of theoretical and scientific foundations of technological methods of realization of intensive shear deformation in the field of longitudinal rolling and can be applied to justify new technology of industrial production of rolled metal products.

Development of a scientifically based technological solution for the implementation of intense shear deformations during rolling in calibrated rolls for the production of rolled metal with a high range of mechanical properties.

1) Analytical review of the current state and trends in the development of technologies and methods of pressure treatment, providing a comprehensive improvement in the quality of metals. A measurable indicator is an analytical report on the current state and trends in the development of the problem. 2) Selection and justification of the rolling method in calibers. A measurable indicator is the rolling method, a computer model of the process and the interpretation of the simulation results. 3) Calibration calculation and development of design of rolling rolls and roll equipment, providing the realization of intense shear deformation. Measurable indicator – Technical documentation for the production of rolling rolls and roll tooling. 4) Development of experimental stand for rolling. Measurable indicator – Experimental stand for rolling. 5) Experimental studies of the rolling process. Measurable indicator – Experimental samples of metal and technological regimes of the process. 6) Establishment of regularities of formation of micromechanical properties of metal. The measurable indicator is the indicators of the complex of mechanical properties and the microstructure of the metal. 7) Development of technological modes of rolling in calibers. A measurable indicator is the Technological regulations for the production of rolled metal.

Various technological and constructive ways of implementing intense shear deformations in longitudinal rolling processes have been identified by methods of collecting, processing and analyzing primary information. A rolling method is proposed in the "oval-circle" caliber system, where the main axes of the oval in the calibers are located obliquely relative to the axis of the rolls. The angle of inclination of the main axis of the oval in caliber relative to the axis of the rolls is assumed to be γ = 35 °, which ensures the implementation of a transverse shear in the deformation center simultaneously with high-altitude compression. Computer modeling of the rolling process in an oval caliber with an inclined oval arrangement showed the non-monotonous nature of the metal flow due to the occurrence of vortex plastic flows, which causes the implementation of intense plastic deformations. The parameters of the shape change and geometric ratios of the calibers of the new oval-circle system for rolling in an experimental mill have been determined and design documentation for the manufacture of rolling rolls and roll wiring has been developed. Based on the Johnson-Mail-Avrami-Kolmogorov phenomenological model (JMAK model), numerical modeling of the evolution of microstructure during the implementation of intense shear deformations during rolling in the oval-circle gauge system has been performed. The microstructure parameters for AISI 316 steel are calculated using a dynamic recrystallization model. A comparative analysis of the values and the nature of the cross-sectional distribution of the average grain sizes of materials obtained by rolling according to the traditional and new scheme has been performed. Based on the simulation results, it was found that the implementation of intense shear deformations during rolling in the oval-circle gauge system provides more intensive and uniform grain grinding over the entire strip section compared to the traditional scheme. Confirmation of the heterogeneity of the mechanical properties of the metal in cross-section during rolling according to the traditional rolling scheme has been obtained. The effectiveness of the new rolling scheme in working out the areas of the initial blank most affected by defects has been proven.