The comprehensive analysis of temperature influence on the strain–speed parameters of radial-shear rolling of Al-Zn-Mg-Ni-Fe alloy including the investigation of rheological properties, FEM simulation, and in-depth analytical interpretation of results was carried out. The rolling temperature has significant effect on the kinematic of metal forming, speed parameters, configuration, and length of trajectories. With the decrease in temperature, the speed of metal movement reduces, and this is the same for different components. The greatest decrease is noted for the axial speed component. In general, according to the nature of effect on the strain kinematic state, a temperature reduction of 100 °C (from 500 to 400 °C) acts similarly to a decrease in feed angle of about 4° and, in particular, increases the rolling time, nonuniformity of deformation, tightening, and temperature effect of deformation heating.

The Co–28Cr–6Mo medical alloy after homogenization is tested in uniaxial compression at temperatures of 1000, 1100, and 1200°C and strain

Radial-shear rolling technology (RSR) is a modern, effective technique for obtaining structured semi-finished and final bar products from various metals and alloys, including hard-to-deform ones. Due to design features (feed angle 18–20 °, rolling angle 0–12 °, taper angle of roll 10 ± 2,5 °) implemented in the RSR equipment (mini-mills) and unique trajectory-deformation conditions, the possibility of obtaining ultrafine-grained functional-gradient structure is realized. At the same time, mini-mills are characterized by compactness and versatility of working tools, which allows to reduce labor costs and follow the concept of lean production. This article reviews the industrial application of technology and equipment of RSR and scientific and applied research in this direction by various scientific groups, outlines the elements of theory, as well as the main stages of development and implementation. The reviewed publications indicate the demand for and prospects of application of RSR technology for obtaining products with a unique combination of properties. The study was supported by a grant from the Russian Science Foundation (Project No. 23-19-00477), https://rscf.ru/project/23-19-00477/.

The article analyzes the microstructure evolution of Co-Cr-Mo alloy during isothermal forging. The process of isothermal forging can be a technological solution to produce a semi-finished product for subsequent deformation processing and obtain a high-quality microstructure that excludes casting defects. Based on analysis of microstructure and phase composition and calculations, the required modes of ingot homogenization are determined. Finite element method simulation of the forging has shown that temperature and deformation conditions make deformation in the single-phase γ-region possible. However, at lower temperatures, σ-phase particles may precipitate at the last steps of deformation. After isothermal forging and water quenching, a mixture of recrystallized and polygonized structures with an average grain size of 5–10 μm and precipitation of ultra-fine dispersed particles of σ-phase (~0.13 μm) at grain boundaries are formed. Isothermal forging in the temperature range of 1100–1200 °C and at low strain rates of up to 1 s⁻¹ allows obtaining a microstructure without pores, cracks, and large inclusions. Thus, it makes it possible to use the forging billet for further deformation by different metal forming methods.

Effect of radial shear rolling on the morphology of intermetallic particles, and the mechanical properties of 7075 alloy at different processing temperatures and heat treatment after deformation was investigated. The results were consistent with data on metallographic investigation of phase particle shape, counts, and distribution. It was found that the formation, quantitative distribution, and circularity of particles at the surface and in the centre of the bar depended on the processing temperature and temperature gradient between surface and centre and were defined with a scheme of stresses in the deformation zone. The values of strength properties for all bars obtained by RSR depended on the processing regimes, while plasticity (elongation to failure δ = 14%–20%) increased with the growth of processing temperature. Article highlights Radial shear rolling makes it possible to obtain aluminium alloy bars with a gradient structure and a combination of high strength and ductility. The influence of the RSR method is reflected in the nature of the distribution of dispersive particles in the matrix of alloy. Mechanical properties of bars subjected to the RSR method depend on the initial processing regimes, while the level of plasticity increases with the growth of processing temperature.

Numerical simulation of metal forming processes is finding increasingly wide applications in advanced industry for the optimization of material processing conditions and prediction of process parameters, finally delivering a reduction of production costs. This work presents a comparison between simulation results of radial shear rolling (RSR) of VT3-1 titanium alloy (Ti-Al-Mo-Cr-Fe-Si) and results of experimental RSR at 1060 °C, 980 °C, and 900 °C in one, three, and five passes, respectively. The digital model (DM) demonstrates a high convergence of the calculation results (calculation error of less than 5%) with the actual geometric parameters of the experimental bars, their surface temperature, and rolling time during the experiment, which indicates a good potential for its application in the selection of deformation modes. Based on the simulation and experimental data, the conditions providing for the formation of differently sized grains in the bar cross-section have been identified. All of the as-rolled bars exhibit a gradient distribution of macrostructure grain size number (GSN), from the smallest one at the bar surface (2–4) to the greatest one in the center (4–6). The macrostructure GSN correlates with the workpiece temperature, which is the highest in the axial zone of the bars, and with the experimentally observed high plastic strain figures in the surface layers. It was found that, depending on the temperature conditions and reduction ratio per pass, any minor change in the values of process parameters can lead to the formation of macrostructures with different grain size numbers.