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Structural data and dependences of the film resistance on magnetic field strength R(H) are presented for Co–Gd and Al–Co–Gd alloy films obtained by vacuum sputtering. It has been found that amorphous Co55Gd45 films show ferromagnetism at room temperature. Singularities observed in the run of R(H) curves for Al84Co8Gd8 and Al92Co6Gd2 films are associated with magnetic ordering in the films.

—Samples of a diamond blend (DB) are processed in supercritical isopropanol using a specially designed unit, and the IR spectra, Raman spectra, and X-ray diffraction data before and after processing are analyzed. It is shown that a noticeable decrease in the intensity of the IR absorption bands of the oxygen-containing bonds is observed as a result of this process, which is indicative of the effective etching of the shell of diamond crystallites during processing. A noticeable increase is found in the half-width of the diamond line in the Raman spectra of the samples subjected to processing, which is determined by the decrease in the dimensions of diamond nanocrystallites due to the etching of the surface defect layer. The proposed method has significant advantages over a traditional acid-based technology of purification of a diamond blend and indicates the prospect of practical application for this process.

The structure and mechanical properties of pearlitic steels, which contain ~0.6% carbon and copper in the amount of 1.25 and 1.4%, have been studied in the states immediately after the pearlitic transformation (with different rates of cooling) and after tempering at 500°C. It has been established that tempered pearlitic steel with copper is 10–15% stronger than the steel of similar composition without copper. The strengthening of copper-containing pearlitic steel after tempering is caused by the precipitation of copper particles 5–20 nm in size in the ferritic regions of pearlite and in grains of free ferrite.

Specific features of the precipitation of 10–30-nm copper particles (Cu-phase particles) in a Fe-C-Mn-Cu steel in the course of pearlitic transformation and subsequent tempering at temperatures of 500–650°C have been studied. It has been shown that, upon the completion of the pearlitic transformation the Cu phase precipitates on cementite plates and in ferrite interspaces (primarily on dislocations). For a Fe-C-Mn-Cu-V steel, the influence of vanadium-carbide precipitates at the interface in the course of the pearlitic transformation on the process of the precipitation of the Cu-phase particles during subsequent tempering has been studied. The effect of the precipitation hardening of the pearlitic steels due to the precipitates of the Cu-phase particles has been assessed.

The peculiarities of the structure of the heat-affected zone (HAZ) of high-strength chromiumnickel-molybdenum shipbuilding steel before and after high-temperature tempering are examined. It is demonstrated that the type and morphology of structural components as well as the carbon redistribution, which depend on the cooling rate and the tempering degree, determine the HAZ hardness and impact strength.

In high-carbon vanadium steel, the temperature range (600°C and higher) and time (∼0.1 s) of the formation of vanadium carbide particles 5–10 nm in size at the interphase boundary upon pearlitic transformation have been established. Their distribution in ferrite has been subjected to crystallographic analysis with allowance for the habit of cementite plates. Based on the results of this analysis, a model has been suggested for the volume distribution of vanadium carbide nanoparticles in ferrite interlayers between cementite plates of the pearlitic colony in the form of successive (periodic) corrugated spherical surfaces with a period of ∼20 nm. This particle distribution is determined by the shape of the moving pearlite-austenite interphase boundary and by the direction of growth of the pearlitic colony.

The technique and the results of studying slightly etched fracture surfaces of samples of carbon steel in structural states with a large fraction of carbides (pearlite, bainite, tempered martensite) are given. The technique presented made it possible to reveal, directly on the facets of brittle transcrystalline and intercrystalline fracture, elements of a microscopic and fine macroscopic structure that have undergone fracture.

It has been shown that upon pearlitic transformation of a high-carbon vanadium steel, vanadium carbides 5–10 nm in size precipitate in the ferrite interspaces of the pearlite in the form of periodic rows (with a period of ∼20 nm). A correspondence between the distribution of vanadium carbides and the shape of the γ/α interphase boundary in the pearlite has been found. It has been supposed that in commercial steels the pearlitic transformation is accompanied by the formation of segregates of different atoms at the discretely moving γ/α interphase boundary.

Structural parameters of pearlitic steel, which determine mechanical properties and specific features of fracture under loading by static bending, have been studied. It is shown that the decisive role in strengthening belongs to the pearlite dispersity and that the main factor responsible for the high plasticity and high fracture energy is the refinement of the initial grain and pearlite colonies. Fine particles have been found to exert plasticizing effect on the pearlite structure upon brittle fracture.

Theoretical and experimental study of the evolution of the dislocation structure in pearlite during fatigue tests using contact and bending modes of loading has been performed. Special features of the dislocation structure of pearlite with a different degree of the structure fineness upon cyclic loading have been analyzed. It has been shown that a size structural effect is realized in the pearlite, which manifests itself in the dependence of the arising dislocation structure in the ferrite interlayers on their thickness. The model of the initiation of a fatigue crack in pearlite has been developed and the period of its initiation under contact cyclic loading has been calculated. Microstructural changes upon the fatigue failure of a high-carbon pearlitic-ferritic steel with different degrees of pearlite fineness have been studied electron-microscopically during contact and bending cyclic deformation.

A new method for determining the physical parameters, ionizing Lyman continua (Lyc) and chemical compositions of HII regions in blue compact dwarf galaxies is developed. We propose our modified NLEHII method, which is independent on the initial mass function (IMF) for the determination of the Lyc spectra of the ionizing nuclei of HII regions. This method is based on the assumptions of ionization-recombination and thermal equilibria in the HII regions. It is used to calculate the Lyc spectra for optimization photoionization models (OPhMs) of HII regions in an iterative way, since the Lyc spectrum depends on parameters that can be found from photoionization modeling. We apply this method to determine the chemical composition of an HII region in the blue compact dwarf galaxy SBS 0940+544 and, in particular, the helium mass fraction Y.

Specific features of plastic deformation and tensile failure of a plain carbon (C = 0.62%) pearlitic-ferritic steel with various pearlite fineness have been investigated. It is shown that the steels with coarse lamellar pearlite and fine lamellar pearlite have similar strain-hardening coefficients, but the relative elongation of the former steel is higher. Deformation results in a uniform dislocation distribution in the fine pearlite and in the formation of a cellular substructure in the coarse pearlite. It is established that the fine pearlite undergoes plastic deformation and ductile failure as a single structure, while the coarse pearlite exhibits a structure discontinuity upon deformation. A model of microplastic pearlite deformation and the initial stage of macroplastic pearlite deformation is proposed. It is established that the strain-hardening coefficient of pearlite at the initial deformation stage does not depend on its dispersity. A size effect, which manifests itself in the dependence of the dislocation structure formed in the ferrite interlayers on their thickness, is shown to be characteristic of pearlite deformation.

Radio-frequency magnetic and dissipative properties of La0.6Sr0.2Mn1.2O3 and La0.65Sr0.28Mn1.07O3 ceramics have been studied in the region of their Curie points. It is established that, despite relatively high conductivity in the frequency range f=1–15 MHz, the screening of samples by the skin current is negligibly small and the ceramic samples behave like strong ferromagnets. This behavior is explained by significant differences in the propagation of electromagnetic field in inhomogeneous granular ferromagnetic media and normal metals. The field dependence of the effective magnetic susceptibility of both manganites has been studied at room temperature.

The specific features of magnetoacoustic waves propagating in an orthorhombic antiferromagnet with weak ferromagnetism, namely, the Fe3BO6 orthoborate, are investigated experimentally in the vicinity of the spontaneous, first-order orientational phase transition. It is revealed that, at the phase transition point, the amplitude of active acoustic waves interacting with spin waves increases significantly. A phenomenological theory of magnetoelastic waves in orthoferrites is proposed. This theory allows for an intermediate domain structure existing in the range of a first-order orientational phase transition and offers a satisfactory explanation of the experimentally observed anomaly in the amplitude of active acoustic waves.