卷 120, 编号 2 (2019)

This work studied the features of solitons inseparable from the domain structure using a ferromagnet with an easy-axis anisotropy type as an example. It has been shown that such solitons are carriers of macroscopic shears in the structure. They serve as remagnetization nuclei of the material under certain conditions. Near the boundaries of the region of their existence, they cause magnetization reversal of the domain structure, as well as a shift of its individual domain walls and the rotation of magnetization in the domains.

The relationships which interconnect parameters of static magnetic hysteresis loops, namely, hysteresis losses, coercive force, and remanence, have been obtained. These relationships arise from the similarity of dimensionless hysteresis quantities in the magnetic field range corresponding to the increase in the magnetic permeability. An experimental check was performed using the soft magnetic nanocrystalline Fe_72.5Cu₁Nb₂Mo_1.5Si₁₄B₉ alloy. It was shown that, at given values of magnetic induction B_max and magnetic field H_max, the required hysteresis quantity can be calculated using experimental values of the other hysteretic quantities.

This work studies the effect of irradiation defects induced by ¹³²Xe²⁷⁺ (167 MeV), ⁸⁶Kr¹⁷⁺(107 MeV), and ⁴⁰Ar⁸⁺(48 MeV) ions on the critical properties of the second-generation superconducting GdBa₂Cu₃O_{7 –x}-based ribbons (free from copper coating) produced by the SuperOx domestic company. Dependences of the critical current at 77 K in the self magnetic field and the critical temperature and width of the superconducting transition on the ion-irradiation fluence have been obtained. The ion-irradiation resistance of superconductor has been determined. The critical ion fluence value, at which the critical temperature is zero, was used to estimate the track radii in the superconductor.

Transmission electron microscopy, X-ray diffraction analysis, and microindentation were used to study the changes in the structure, phase composition, elastic modulus, and hardness of the Ti–(9.6–34) at % Nb alloys after quenching in water from heating temperatures corresponding to the β region. The relationship between the physicomechanical properties (elastic modulus, microhardness) and the volume fraction of metastable phases detected in Ti–Nb alloys after quenching from the β region has been shown. It has been noted that the Ti–13.3 at % Nb alloy with a structure in which the ω phase with anomalous morphology in the form of massive plates is formed after quenching is characterized by maximum values of elastic modulus and microdurometric characteristics. The growth of the elastic modulus of the metastable β solid solution with increasing niobium content in alloys with a decrease in the average distance between the niobium–niobium atoms in the bcc structure has been justified. The possibility for calculating the elastic modulus of quenched Ti–Nb alloys based on the additive contributions of the elastic moduli of phases detected after quenching, which are proportional to their volume fractions has been considered.

This paper presents results of the structural study of the Ti₅₀Ni₂₅Cu₂₅ alloy formed under rapid quenching from a melt. The studies were performed using neutron and X-ray diffraction and transmission and scanning electron microscopy. It has been revealed that this alloy has an amorphous nanocrystalline structure, which contains В2, L2₁, and L1₂ ensembles of nanocrystals with sizes to several nanometers in an amorphous matrix alongside with microspherolites, which have sustained the thermoelastic В2–В19 martensitic transition. It has also been shown for the first time that topological and compositional short-range atomic order is formed in the amorphous matrix of the Ti₅₀N₂₅Cu₂₅ alloy in the form of localized nanodomains by the same three types of superstructures (В2, L2₁, L1₂).

The effect of high-pressure torsion (HPT) deformation on the structure and hardening of three-layered hybrid steel/copper/steel material and its components has been studied in this work. The HPT of the three-layered steel/copper/steel blank results in the formation of a strong boundary between layers, which is mainly smooth, and in an increase in their strength. However, no maximally possible values of microhardness of the outer steel layers of the hybrid are reached because of the absence of ultrafine-grained structure in them.

This work presents the results of a comprehensive study of the structure, phase composition, mechanical and tribological characteristics of vacuum deposited chromium–carbon coatings of two different types. These two types are chromium-doped diamond-like coatings obtained by reactive magnetron sputtering of chromium in argon and in mixtures of acetylene with nitrogen; and coatings obtained by sputtering in argon of a target made by sintering of chromium powder and detonation-produced nanodiamonds. It has been shown that the features of the tribological behavior of these coatings at high contact pressures can be explained by the character of carbon phase distribution and differences in its structural state.