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.

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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.

Elaboration of modern domestic structural materials with increased corrosion resistance in contact with advanced heatcarriers of future reactor plants is an important problem at development of innovation projects of nuclear power engineering. Heatexchanging tubes are the critical components, which influence on the safety and reliability of steam generators operation. Corrosion properties of non-stabilized nitrogen-containing corrosion resistant steels of austenite class after cold deformation, thermal treatment and long-term thermal aging studied. It was shown, that silicon introducing into chrome-nickel steel, alloyed by nitrogen and molybdenum, results in increasing of its resistance against local kinds of corrosion and equated it on resistance against intercrystallite and pitting corrosion with particularly low-carbon steels and alloys. But the experimental 03Х18Н13С2АМ2ВФБР-Ш low carbon micro-alloyed steel, proposed for operation at a heat-carrier temperature of 450–500 о С, in the first version had a tendency to a decrease of resistance against local corrosion and impact resistance after long-term thermal aging at temperatures of 360 о С and higher. At present specifying of technological parameters of production and balanced alloying element content takes place, which prevents heat exchanging tubes properties degradation. Steel 03Х17Н13С2АМ2 which has higher resistance against local corrosion and strength comparing with 316LN and 08Х18Н10Т grades, can be taken as a candidate material for production of heat-exchanging tubes of steam generators of nuclear power stations having power reactors of water-water type. The new 03Х17Н9АС2 steel, resistant against inter-crystallite corrosion in high-oxidizing media, was proposed for tests of its operation under conditions of contact with lead heat-carriers instead of 10Х15Н9С3Б1-Ш (ЭП 302-Ш) steel.

In the article, the tests of the medical alloy Co – 28Cr – 6Mo after homogenization for uniaxial compression at temperatures of 1000, 1100 and 1200 °C and strain rates of 1, 10, and 50 s­–1 were carried out using the Gleeble System 3800. The stress-strain curves describing the alloy deformation behavior were obtained. The calculations of hot deformation parameters (activation energy, Zener-Hollomon parameter) were performed using three models (power-law, exponential, and hyperbolic sine function) describing the flow stress. The highest degree of convergence was shown by the calculation results based on the power function and the hyperbolic sine function. These models can be used to accurately calculate the flow stress at given temperature and strain rate parameters, or to simulate the deformation process. Also, based on processing maps, the authors developed the deformation-speed modes of hot deformation of the Co – 28Cr – 6Mo alloy. It will make it possible to choose the optimal rolling modes in the future. According to the data obtained, favorable temperature-speed conditions for hot deformation are shifted as deformation accumulates to the region of high temperatures and low strain rates. At the same time, the extremely unfavorable zone with negative values of the ξ-criterion, which appears at e = 0.3 – 0.4, continues to grow quite significantly with an increase in the deformation effect. Hot deformation of the Co – 28Cr – 6Mo alloy at low compression ratios (e < 0.2) is more expedient to perform at temperatures above 1150 °C and strain rates of at least 20 s–1. With an increase in deformation degree, it is necessary to choose lower strain rates (1 – 5 s–1) and higher deformation temperature.

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