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CrAlSiC films deposited under various conditions of carbon-plasma generation (PVD or PACVD) are investigated. A plasma source of cathodic-arc discharge with a Cr–Al–Si cathode and a source of pulsed cathodic-arc discharge with a graphite cathode are used for the deposition of a CrAlSiC(I) film. A plasma source of cathodic-arc discharge with a Cr–Al–Si cathode and a gas-discharge device for generating a non-self-sustaining discharge in an argon-acetylene mixture are applied for the deposition of a CrAlSiC(II) film. The sources work together in both processes. The film structure is investigated using electron microscopy and Raman spectroscopy. The hardness and elasticity modulus are determined by nanoindentation; the friction coefficient is tested with the reciprocating motion of a steel ball without lubrication. It is found that the condition of generating carbon plasma (graphite sputtering or destruction of acetylene) has a significant effect on the structure and properties of CrAlSiC. CrAlSiC(I) consists of an amorphous phase with inclusions of silicon-carbide nanograins 10–30 nm in size. On the surface there are protrusions with a size of 2–4 µm. These features provide a high hardness and low friction coefficient. No crystalline formations are found in the amorphous matrix of CrAlSiC(II). On the surface there are bubble-like formations up to 15 microns in size. This coating is inferior to CrAlSiC(I) in terms of hardness and resistance to friction. Under friction the film is destroyed by chipping fragments. CrAlSiC(I) can be recommended for practical application.

The effect of the frictional treatment with a sliding indenter on the micromechanical properties of the austenitic corrosion-resistant chromium–nickel AISI 321 steel (16.80 wt % Cr, 8.44 wt % Ni) has been investigated. The instrumented microindentation results, which was performed on the surface of the steel and at different depths from the surface, has shown the exponential distribution of maximum hmax and permanent hp indentation depths, Martens hardness HM, indentation hardness at the maximum load HIT, elastic reverse deformation work of indentation We, total mechanical work of indentation Wt, elastic recovery Rе, ratio of indentation hardness to contact elastic modulus НIT/Е*, power ratio $${{H_{{{\text{IT}}}}^{3}} \mathord{\left/ {\vphantom {{H_{{{\text{IT}}}}^{3}} {{{E}^{{*2}}}}}} \right. \kern-0em} {{{E}^{{*2}}}}}$$ , and plasticity index δA over the depth of the hardened gradient layer. In this case, the HM, HIT, We, Rе, НIT/Е*, and $${{H_{{{\text{IT}}}}^{3}} \mathord{\left/ {\vphantom {{H_{{{\text{IT}}}}^{3}} {{{E}^{{*2}}}}}} \right. \kern-0em} {{{E}^{{*2}}}}}$$ values are the highest, whereas the hmax, hp, Wt, and δA values are the lowest for the steel surface. The E* contact elastic modulus of AISI 321 steel also increases after the frictional treatment. It is distributed nonmonotonously over the depth of the hardened layer. This can be explained by the formation of different dislocation structures on the steel surface and in the underlying layers. The indentation results have shown that the frictional treatment increases the resistance to mechanical action of both the steel surface and the hardened layer with a depth of to 500 µm.

In the alloy Fe63.5Ni10Cu1Nb3Si13.5B9, which is conventional FINEMET with Fe replaced by 10 at % Ni, the effects of the temperature and time of nanocrystallizing annealing in the presence of tensile stresses (stress annealing, SA) on the magnetic properties, magnetic anisotropy, and structure are considered. In the entire studied SA temperature range (480–550°С), induced magnetic anisotropy (IMA) of the easy-plane type occurs in the studied alloy. The tensile stresses upon SA were 200 MPa. In the course of SA at the minimum temperature, anisotropy with the minimum IMA constant (200 J/m3) is induced. The maximum SA duration, i.e., 4 h, is required. At SA temperatures of 540–550°С, 10 min is sufficient to induce IMA with the maximum constant ~2000 J/m3. It is shown that the structural state (phase composition) is correlated with the magnetic properties and IMA. Thus, the increase in the coercivity with an increase in the SA duration at 540–550°С (as well as at 520°С) is due to the development of the tetragonal phase in the alloy. The α‑(Fe,Ni)Si solid solution and Fe3Si phases form upon treatment for 10 min. The decrease in the IMA constant with an increase in the SA time at 540–550°С from 10 min to 1 h is most likely due to the change in the volume fractions of the structural components of the alloy with negative and positive magnetostriction.

Results are provided for studying deformation methods of steel surface nanostructuring and hardening with martensitic, pearlitic and austenitic structures. A new method of ultrasonic impact-friction treatment is considered. Combined methods of nanostructuring treatment (friction treatment + annealing) are proposed for a metastable Cr – Ni steel. The possibility is demonstrated of activating steel saturation with nitrogen during plasma treatment due to preliminary nanostructuring friction treatment.

The structure of the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy, which is a classic alloy of the FINEMET type with 10 at % Ni substituted for Fe, has been studied after crystallization in the presence of tensile stresses. It has been shown that, upon the crystallization of the alloy (520°C) both in the presence of a tensile load and without it, nanocrystals of an α-(Fe, Ni)Si solid solution and of the Fe3Si phase are formed with an increase in the duration of annealing from 10 min to 1 hour. When the length of the annealing is further increased from 1 to 4 hours, a tetragonal phase Fe3NiSi1.5 appears in the alloy. A relationship between the structural state (phase composition) of the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy and its magnetic properties and the type of the induced magnetic anisotropy has been shown. The growth of the coercive force, which was previously observed in samples of this alloy as the duration of the annealing was increased to 4 hours, is therefore associated with the appearance of a tetragonal phase in the alloy. The transverse magnetic anisotropy, which is induced in the alloy in the process of nanocrystallizing annealing in the presence of a tensile load, is associated with the formation of nanocrystals of the α-(Fe, Ni)Si solid solution and of the Fe3Si phase with a negative magnetostriction.

The methods of X-ray diffraction analysis and transmission electron microscopy were used to study the structure of coatings based on the Al2Au intermetallic compound. It has been shown that after the deposition, the coating is in an amorphous state. The annealing of the coating at 500°C for 15 min results in initial stages of crystallization. In the annealed coating, signs of a retained amorphous structure and grains of the Al2Au intermetallic compound with a size of 30–100 nm are observed. In addition, a small amount of the intermetallic phase AlAu is fixed in the coating after annealing. Optical characteristics of the annealed sample have been measured; a comparison with literature data on the structure and optical properties of coatings obtained by different methods was performed.

The microstructure of a laser-welded joint between a chromium–nickel austenitic steel and a titanium alloy with an intermediate copper insert has been studied. Using X-ray diffraction analysis, energy-dispersive X-ray microanalysis, and transmission electron microscopy, it has been shown that the welded joint represents a copper-based solid solution with intermetallic particles of (Fe,Cr)2Ti and Cu3Ti 10–50 μm in size, which were the first to crystallize in the welding pool, and intermetallic particles of (Fe,Cr)2Ti and Cu4Ti with a size of no more than 30 nm, which homogeneously precipitate on cooling from the copper-based solid solution oversaturated at the moment of crystallization. The fracture of the joint upon tensile tests occurred along the diffusion zone at the boundary with the titanium alloy. The maximum ultimate tensile strength of such a joint was 474 MPa.

The effect of 10 at % Ni, which was introduced into the classic Finemet Fe73.5Cu1Nb3Si13.5B9 at the expense of the Fe content, on the magnetic properties of the composition has been considered. The alloy was subjected to nanocrystallizing annealing in the presence of tensile stresses and in their absence. It is shown that, similarly to the Ni-free alloy, in the Fe63.5Ni10Cu1Nb3Si13.5B9 alloy subjected to thermomechanical treatment, the magnetic anisotropy with the easy magnetization direction across the ribbon axis (transverse induced magnetic anisotropy) is induced. It was found that the 10 at % Ni addition almost does not affect the value of magnetic anisotropy constant induced under thermomechanical treatment and decelerates the process of magnetic anisotropy inducing at σ ≤ 200 MPa. The Ni-containing alloy subjected to nanocrystallizing annealing (at 520°C) in the presence of tensile stresses and in their absence demonstrates the more than 200-fold increase in the coercive force as the annealing time increases from 1 to 4 h, whereas the coercive force of the Ni-free alloy is almost unchanged. This is likely to be related to the appearance of new structural components in the Ni-alloyed composition upon annealing.

Cu/Mg-composites, the copper matrix of which contains 1, 7 and 2730 magnesium filaments, were obtained by hyrdoextrusion at room temperature. The structure, mechanical and electrical properties of the deformed composite rods and thin wires were investigated. The yield strength and electrical resistivity were theoretically calculated and these estimations were compared with the experimental results. The XRD-method allowed discovering a change of the lattice constant of the Cu-matrix under deformation of the composites. It has been concluded that, under severe plastic deformation, a supersaturated Cu-based solid solution forms on the Cu/Mg-interface. As a result, the strength of the deformed Cu/Mg-composite with minimal volume fraction but maximal surface area of magnesium is abnormally high. A thick Cu-sleeve provides low electrical resistivity of this Cu/Mg-composite. The obtained results can be used for the development of high-strength Cu-based conductors. © 2019 The Authors Ural Branch, Russian Academy of Sciences, UB RAS The work was carried out in the framework of a state task according to the theme ?Pressure? No. AAAA-A18-118020190104-3. The studies of structure and mechanical properties of the samples were carried out at the Electron Microscopy Department and Mechanical Test Department of the Collective-Use Center of the Institute of Metal Physics (Ural Branch, Russian Academy of Sciences). The X-ray diffraction studies were carried out in the ?Composition of Compounds? Center of Collaborative Access, Institute of High-Temperature Electrochemistry, Ural Branch, Russian Academy of Sciences.

The influence of heat treatment in the 100–900°С temperature range on the phase composition, structure, and micromechanical characteristics of the surface layer of the 12Kh18N10T steel subjected to nanostructuring frictional treatment (FT) with a sliding indenter has been studied. This study considered opportunities for strengthening metastable austenitic steel using combined thermomechanical treatments. Annealing at 400–450°C allows for the retention of nanocrystalline martensitic–austenitic structures formed in the surface layer of the steel and a significant increase in the micromechanical characteristics owing to the strengthening of the strain-induced martensite. The annealing of the steel at 650°C leads to the formation in the surface layer of an austenitic predominantly submicrocrystalline and nanocrystalline structure with a hardness of 630 HV 0.025, which is almost 3 times higher than the hardness of steel in the initial quenched state. The transmission electron-microscopic studies of the surface layer of the austenitic steel deformed by FT made it possible to reveal the retention of highly dispersed austenitic regions in addition to the recrystallized regions upon heating to 800°C, as well as the absence of abnormal growth of recrystallized austenite grains upon heating to 900°C.

In this first part of the work, the microstructure, surface roughness, residual stresses, microhardness and micromechanical properties of the high-carbon (1.03 wt% C) steel with a fine-lamellar pearlitic structure have been studied before and after frictional treatment with a sliding indenter. It has been found that the frictional treatment is a nanostructuring treatment, which forms a high-quality surface with low roughness (Ra = 0.065 µm), leads to a significant surface hardening (microhardness increases from 450 to 1040 HV0.05) and forms favorable residual stresses in the hardened surface layer. The instrumented microindentation data also testify to substantial hardening of the steel after the frictional treatment and increased resistance of the steel to intensive mechanical contact. Tensile properties and the experimental verification of the ability of the high-carbon steel with different structural states of its surface to withstand contact loads will be presented in the second part of this work.

The structure of Al2Au intermetallic compound mechanically synthesized from a nanoscale gold powder and aluminum particles of about 0.5 mm in size has been studied by X-ray diffraction and transmission and scanning electron microscopy. It has been established that the intermetallic compound is formed as a powder with a particle size of 0.3–3 μm. In addition to intermetallic compound, some aluminum has been found in the powder, along with traces of gold and aluminum oxide Al2O3, and the appearance of an amorphous phase has been registered. The microstructure of compacts formed from the obtained powder has been studied, and heat treatments have been carried out. It has been found that compacting and subsequent annealing contribute to the agglomeration of intermetallic particles. Increasing the treatment temperature to 600°C results in the refinement of the structural elements as a result of their cracking in the surface layer. Compacts that are dark purple in their original state acquire a color ranging from pink to dark red as a result of annealing. After heat treatment, the presence of Al2O3, as well as of intermetallic phases enriched in gold (AlAu and AlAu4), has been detected in compacts in addition to the intermetallic compound Al2Au.

Methods of Mossbauer spectroscopy and electron microscopy have been used to study the effect of the severe plastic deformation by high pressure torsion in Bridgman anvils on the dissolution and precipitation of chromium nitrides in the austenitic and ferritic structure of an Fe71.2Cr22.7Mn1.3N4.8 high-nitrogen steel. It has been found that an alternative process of dynamic aging with the formation of secondary nitrides affects the kinetics of the dissolution of chromium nitrides. The dynamic aging of ferrite is activated with an increase in the deformation temperature from 80 to 573 K.

The evolution of the structure, microhardness, and electrical resistivity has been studied during prolonged low-temperature annealings of the Cu-8 at % Pd alloy. An increase in the microhardness and electrical resistivity after annealings at temperatures of 250 and 300°C has been revealed; the preliminary deformation significantly accelerates and enhances this effect; and the X-ray diffraction patterns remain unchanged and correspond to an fcc solid solution. Using transmission electron microscopy, the state of an atomic short-range order has been detected in the quenched alloy; prolonged annealings of the deformed alloy lead to the formation of microregions of the ordered L12 phase.

For the purpose of developing materials with optimum magnetic properties for high-temperature applications (500–600°C), we have investigated the magnetic properties and structure of a nanocrystalline (Fe0.7Co0.3)88Hf4Mo2Zr1B4Cu1 alloy. The alloy was subjected to nanocrystallizing annealing (NA) at 620°C in the presence of an alternating magnetic field (magnetic heat treatment, MHT). The influence of the duration of the NA and of the amplitude value H amp of the ac magnetic field on the magnetic properties of the alloy and on their thermal stability has been studied. It has been established that the MHT carried out at 620°C is most efficient after holding in a magnetic field for 20 min. In this case, a decrease in the coercive force and an increase in the remanence have been observed. An increase in the time of the holding upon the MHT from 20 min to 4 h decreases the efficiency of the treatment. It has been shown that the MHT carried out at 620°C for 2 h and H amp = 9 kA/m leads to the smallest changes in the magnetic properties of the alloy after the subsequent holding at a temperature of 550°C for 30 h. However, this treatment does not ensure the thermal stability of the magnetic properties of the alloy at 550°C achieved earlier after the nanocrystallization of the alloy at 620°C for 20 min in the presence of tensile stresses (250 MPa).

The effect of a high dc magnetic field (up to 29 T) applied during the crystallizing annealing of amorphous ribbons on the structure of Fe81Si7B12 and Fe73.5Cu1Nb3Si13.5B9 alloys has been studied. In the Fe81Si7B12 alloy, an increase in the average size of grains that form during magnetic annealing has been revealed; in the Fe73.5Cu1Nb3Si13.5B9 alloy, a small decrease is observed in the average grain size. The possible reason for this may be the differences in the specific features of the processes of crystallization of these alloys. No effect of the magnetic field on the crystallographic orientation of the arising grains has been revealed.

Using transmission electron microscopy, X-ray diffraction analysis, Mossbauer spectroscopy, microdurometry, and microindentation, the effect of large plastic deformations (through shear under pressure in Bridgman anvils) on the structure, phase composition, and micromechanical properties of high-nitrogen (1.24 wt % N) 08Kh22GA1.24 steel has been investigated. The steel was obtained by the casting method with counterpressure of nitrogen and was subjected to different heat treatments (quenching from1180°С, aging at 450 and 550°С) that form an austenitic (FCC) structure of the metallic matrix with chromium nitrides. It has been established that deformation by shear under pressure at room temperature results in the dispersion and deformation-induced partial dissolution of primary nitrides Cr2N in quenched and aged steel and in the complete (after aging at 450°С) and partial (after aging at 550°С) dissolution of secondary nitrides CrN. It has been noted that, for aged steel that contains finely dispersed secondary chromium nitrides upon shear deformation, as compared to the quenched state, the dispersion of the austenitic structure (down to nano- and submicrocrystalline states) is more intense and the enhancement in the microhardness and resistance to elastic–plastic deformations upon contact loading is more effective.

The structure and micromechanical properties of a 316L stainless steel produced by the selective laser melting (SLM) technique have been studied in its initial state and the following heat treatment: quenching from 1050 ºС and 4-hour annealing at 480 ºС. The heat treatment does not result in changing the steel phase composition, however, it reduces the microhardness by 5%, HM hardness (Martens hardness) by 12% and indentation hardness by 16% at HIT maximum load. The heat treatment also increases the Е* contact elasticity modulus by 14% due to the lower porosity of the material. As soon as heat treatment provides no strengthening of the steel synthesized by SLM, deformation processing, chemicothermal treatment and application of thin coatings may become quite promising strengthening methods. © 2020 Institute of Physics Publishing. All rights reserved. The main results were funded by the RFBR and Sverdlovsk Oblast, project number 20-48-660065. The results of the electron diffraction phase analysis were obtained by the M.N. Mikheev Institute of Metal Physics of the Ural Branch of the Russian Academy of Sciences (IMP UB RAS) within the state assignment of Ministry of Science and Higher Education of the Russian Federation (theme “Structure” No. № АААА-А18-118020190116-6). The studies were performed at the collaborative access center “Testing center of nanotechnology and advanced materials” of IMP UB RAS.

The effect of conditions of heat treatment on the microstructure and mechanical characteristics of an LN-1 alloy (Nb–10W–5Mo–1.5Zr–0.15C), which is used to produce high-temperature springs, has been studied. The temperature conditions of annealing of the alloy have been chosen, under which the fairly high ductility needed for the subsequent deformation of the alloy is achieved. Structural examinations have revealed the formation of fine niobium–zirconium carbides in the matrix in the course of the thermomechanical strengthening of the alloy, which involves preannealing.

The possibility of obtaining the shape-memory effect as a result of the γ → e → γ transformations in aging stainless steels strengthened by VC carbides has been investigated. Regimes are given for strengthening aging (at 650 and 720°C) for stainless steels that predominantly contain (in wt %) 0.06–0.45C, 1–2V, 2–5Si, 9 and 13–14Cr. The values of reversible deformation e (amount of shape-memory effect) determined after heating to 400°C in samples preliminarily deformed to 3.5–4% vary from 0.15 to 2.7%, depending on the composition of the steels and regimes of stabilizing and destabilizing aging.

Aim. To compare two therapies based on carvedilol or metoprolol in hypertensive patients with overweight and obesity.Material and methods. 320 patients with arterial hypertension (1-2 degree) were involved in the study. 160 patients received carvedilol and 160 patients – metoprolol. Both randomized groups were comparable on the main clinical characteristics.Results. By the end of the study both systolic and diastolic blood pressure (SBP, DBP) reduced in both groups рConclusion. The results of open, randomized CAMELLIA trial confirmed antihypertensive effect and good tolerability of carvedilol in common clinical practice as well as demonstrated some its advantages in patients with metabolic syndrome. Carvedilol has positive metabolic effects on lipid, glucose and uric acid levels. Carvedilol therapy is more preferable in patients with arterial hypertension and metabolic risk factors.

The microstructure, mechanical and electrical properties of Cu-Pd alloys (with Pd content not more than 8 at.%) and triple Cu-Pd-Ag alloys with 5 at.%Ag were studied. It was established that the strength and the recrystallization temperature of the Cu-Pd alloys increased with palladium content. A comparison of the electrical properties of these alloys when Pd content was increased from 0 to 8 at.%Pd was done. An anomaly was revealed in the Cu-5.9Pd and Cu-8Pd alloys: the plastic deformation does not lead to an increase in the electrical resistivity. It is due to the destruction of short range atomic order in the quenched Cu-Pd alloys under deformation. The alloying with silver leads to a further increase in strength with a constant electrical conductivity. It was found that annealing of the deformed Cu-Pd-Ag alloys at 200-300°C led to an increase in strength. It was shown that the effect was not related to the Pd-content and was due to silver only.

The parameters of the structure and phase composition of austenitic structural steels subjected to frictional treatment with a sliding indenter were studied by X-ray diffraction and transmission electron microscopy. It has been found that the strengthening of deformation-stable austenitic steel was due to the formation of finely divided austenite, with the intensification of the grain-boundary and dislocation strengthening mechanisms. Additional strengthening of metastable austenitic steel was due to the formation in the surface layer of about 70% of the volume fraction of nanocrystalline strain-induced martensite. It is proposed to use nanostructuring frictional pretreatment as a promising method for hardening austenitic structural steels before the subsequent application of superhard, dead-hard, and heat-resistant nanocomposite coatings.

The kinetics of the A1→B2 phase transition in the cryogenically deformed Cu-47at.%Pd alloy has been compared with that both after room-temperature deformation and after quenching from high temperature. For this aim, the evolution of the microstructure, electrical properties and microhardness of the alloy during disorder→order transformation at 400 °C were studied. It was shown that annealing at 400 °C for 1 h led to the formation of a uniform ultrafine-grained ordered structure in the cryo-deformed alloy. In turn, the annealing duration of 1 h is not enough to finish the ordering process in the quenched sample. It was found that some volume of the ordered B2-phase was formed in the cryo-deformed Cu-47at.% Pd alloy after holding at room temperature for 0.5 year.

Boron based ceramic coatings were deposited on steel substrates by high-energy short pulse laser melting. Under conditions of the laser deposition, coatings consisted of boron carbide and boron nitride form a layer that acts as solid lubricant leading to a low coefficient of friction (COF). The COF could be drastically decreased by proper selection of chemical composition of boron based ceramic coatings. Ultimately low COF of 0.03 was registered during dry sliding tests of coatings with addition of different metal oxides (MgO, ZrO2, Li2O). Low COF of composite ceramics coatings was attributed to the formation of the B O bond observed by the X-ray photoelectron spectroscopy technique. This bond as the essential component of the internal structure of coatings explains ultralow friction behaviour and remains low even during gradual deterioration of the coating. High quality adhesion of ceramics to steels was explained by reactive phase formation at the steel-ceramic interface, which was confirmed by both transmission electron microscopy and X-ray diffraction.

The deformation behavior of (Fe83.4Ga16.6)99.9NbC0.1 non-textured polycrystalline alloy during hydrostatic extrusion was investigated. Cold deformation 53% of the as-cast sample without prior high temperature deformations was achieved. In the process of deformation, a sharp axial texture develops. The deformation mechanisms are both slip induced crystal rotation and twinning. The development and growth of other orientations including the desired occur during primary recrystallization. The EBSD method was used to study the features of these phenomena. The volume fraction of preferential orientations after various modes primary recrystallization was estimated. volume fraction amounted 14.4 and 18.6% after annealing 800 and 950 °C respectively. A correlation between the texture of recrystallization and magnetostriction was established.

Frictional treatment (FT) with a sliding indenter forms highly dispersed (nano- and submicrocrystalline) austenitic structures with a hardness of 720 HV 0.025 in the surface layer of the 03Cr16Ni14Mo3Ti austenitic strain-resistant steel. According to the data on microindentation, FT increases the strength and of the surface layer of the austenitic steel and its resistance to elastic and plastic deformation. A high effectiveness of FT in the improvement of the tribological properties of the steel is demonstrated; namely, wear resistance increases 4 times under conditions of boundary friction as compared to the undeformed state. This is due to reduced plastic edging on the nanostructured surface.Frictional treatment (FT) with a sliding indenter forms highly dispersed (nano- and submicrocrystalline) austenitic structures with a hardness of 720 HV 0.025 in the surface layer of the 03Cr16Ni14Mo3Ti austenitic strain-resistant steel. According to the data on microindentation, FT increases the strength and of the surface layer of the austenitic steel and its resistance to elastic and plastic deformation. A high effectiveness of FT in the improvement of the tribological properties of the steel is demonstrated; namely, wear resistance increases 4 times under conditions of boundary friction as compared to the undeformed state. This is due to reduced plastic edging on the nanostructured surface.

Kh16N15M3T1 and Kh13V2 reactor steels were investigated. The study was carried out using a light-gas gun with the deformation velocities ranging from 4·104 to 3·106 s-1 and shock-loading pulses in 0.05-1 μs duration range. Dependences of the spallation strength and dynamic elastic limit in a wide temperature range are obtained. The recovered specimens were used to carry out the metallography analysis.

With two structural steels (the steels 50 and 09G2S) as examples, the paper studies the effectiveness of a new method of ultrasonic impact-frictional treatment (UIFT) for the hardening and nanostructuring of the surface layer with the variation of the tilt angle of the vibrating indenter and the treatment environment. It is demonstrated that treatment with tool tilt angles different from 90° and with the absence of a contact liquid results in the formation of a nanostructured surface layer with increased microhardness. © 2018 Author(s).

Aim. To prove the advantage of the long-term controlled antihypertensive therapy compared with the real usual standard therapy in patients with mild to moderate arterial hypertension.Material and methods. It was multicenter, randomized, prospective parallel-group study in patients with mild to moderate hypertension. One part of patients (treatment group) received the strongly regulated stepped antihypertensive therapy based on ACE-inhibitor spirapril, the second one (control group) continued their usual standard therapy prescribed by doctors of polyclinics or other patient care institutions. The study lasted one year.Results. 1742 patients were enrolled in the study, 854 patients were included in the treatment group and 888 – in the control group. 220 patients dropped out of the study by different reasons, and 1552 patients finished the study. There were 651 (37,6%) men and 1081 (62,4%) women. It was substantial decrease in blood pressure in both group, but distinctions between systolic and diastolic blood pressure in the treatment and control group during the study were significant.The target levels of blood pressure (systolic < 140 mm Hg and diastolic < 90 mm Hg) were registered substantially more frequent in the patients of treatment group than in control group (69,4% и 39,3% after three months and 83,6% и 66,9% after 12 months of the treatment correspondingly).Conclusion. Controlled stepped antihypertensive therapy resulted into more significant decrease in systolic and diastolic blood pressure and more frequent achievement of target levels of blood pressure in comparison with control group. It supposes better prognosis of patients.

For the first time the influence of a high direct current (DC) magnetic field on the structure and texture formation in tapes of Ni 48.8 Fe 51.2 alloy was investigated. Cube texture formation was studied in tapes after cold rolling to 98.8% and annealing in a high magnetic field up to 20 T. Samples were subjected to magnetic annealing below and above the Curie point. Structure and texture were studied using electron backscatter diffraction (EBSD) technique, transmission electron microscopy, and magnetic hysteresis loops measurements. The experiments show a significant increase of the {001}±10° volume fraction in the recrystallization texture with the main orientation {100}〈001〉, when the magnetic annealing is carried out at a temperature below the Curie point.

Magnetic properties, structure and thermal stability of the (Fe0.7Co0.3)88Hf2W2Mo2Zr1B4Cu1 alloy ribbon after its nanocrystallization at 620-750°C for 0-20 min in the presence or absence of tensile stresses σ were studied. It was shown that under the effect of tensile stresses a longitudinal magnetic anisotropy with an easy magnetization axis parallel to the long size of the ribbon was induced in the alloy. A better thermal stability of magnetic properties was observed for the alloy subjected to the nanocrystallization annealing at 620° for 20 min with σ = 170 MPa. After the subsequent annealing at 570°C for 25 h without σ, the magnetic properties of the alloy are unchanged. Increasing of the nanocrystallization annealing temperature up to 670-750°C did not result in improvement of the thermal stability of magnetic properties.

The effect of the temperature of nanocrystallizing annealing (NA) at temperatures of 670–750°C on the magnetic properties, structure, and thermal stability of the (Fe0.7Co0.3)88Hf2W2Mo2Zr1B4Cu1 alloy has been studied. The NA was performed both in the presence of tensile stresses applied to samples and in the absence of stresses. It was found that the nanocrystallization of the alloy under applied tensile stresses induces the longitudinal magnetic anisotropy with an easy magnetization axis parallel to the long side of the ribbon. The optimum conditions for nanocrystallization of the alloy, which stabilize its magnetic properties at a fairly high temperature of 570°C, have been determined.

The composition, structure, and properties of films prepared by depositing both titanium and carbon have been investigated. It was found that the films consist of an amorphous carbon matrix with uniformly distributed therein nanoparticles of titanium carbide (less than or equal to 20 nm in size). With increasing carbon concentration above 20 wt %, the film density decreases and the microhardness of the films increases, which reflects the diamond-like nature of the amorphous constituent of the composite film.

Laser welding of dissimilar materials is characterized by high radiation power density, penetration locality, melt convection in the weld pool, and high cooling rates. Therefore, it attracts the attention of developers of high-speed vehicles, who aim at utmost reducing the weight of structures via dissimilar materials welding. The crystallization mechanisms of the weld material govern the structure and strength of welded joints and require a detailed study. This study shows that laser radiation power and welding speed influence crystal forms of welds joining a titanium alloy and a chromium-nickel steel through a copper insert, their structure and tensile strength. At a power of 1.0 kW and a welding speed of 0.3 m/min, the largest amount of each of the alloys is melted in the weld pool and a wide weld is formed, the solidification being accompanied by dendrite formation. The increase in radiation power to 2.4 kW decreases the amount of the molten alloys in the weld pool thus forming welds narrower than 1.8 mm. The increase in the welding speed to 1 m/min inhibits formation of dendrites; in this case, (Fe,Cr)2Ti and Cu3Ti intermetallic particles are the first to solidify and the polyhedral crystals of the supersaturated copper-based solid solution, where nanodispersed (Fe,Cr)2Ti and Cu4Ti particles precipitate during cooling, are the next. This type of weld structure ensures the tensile strength of the joint comparable to the titanium alloy.

We used the ball milling (BM) technique to synthesize Al2Au intermetallic powder from elementary powders of different sizes. The analyses of the phase composition the powder after BM and the microstructure of the separate particles was carried out by TEM, SEM and XRD methods. Then, we prepared Al2Au coatings by vacuum deposition of the obtained powder onto glass substrates. The microstructure of the coatings before and after annealing at 500 °C for 15 min was studied. We established the presence of some volume of amorphous phase both in the initial powder and in the coating. The optical properties of the annealed coating have good correlation with available literature data.

The intermetallic compound Al2Au has been obtained from gold powder and aluminum particles through mechanical alloying in ball mills. The intermetallic structure was investigated by the methods of scanning transmission electron microscopy and X-ray diffraction analysis. It was found that mechanical alloying resulted in the formation of micro and nano particles of Al2Au. The powder obtained was compacted into tablets. X-ray diffraction analysis showed intermetallic lines and one line belonging to aluminum, within the compact. The structure of compacts after annealing was investigated. It was determined that compacting promoted the agglomeration of intermetallic particles. Further annealing led to the surface depletion in aluminum, cracking and refinement of structural elements. After heat treatment, a phase enriched in gold – AlAu – is registered in the samples.

There was performed a resistometric study of the Cu-8 at.%Pd alloy during heating and cooling with a constant rate. There was made a comparison with the change in the electrical properties of the Cu-5.9 at.%Pd alloy. In the investigated Cu-Pd alloys, the anomalous behavior of electrical properties was revealed: long low-temperature annealing increased the electrical resistivity. It was concluded that nuclei of the ordered L12 phase were formed in the Cu-5.9 at.% Pd alloy. The obtained result is in contradiction with the currently known Cu-Pd phase diagram, where the Cu-5.9Pd alloy is the fcc-solid solution. The critical temperatures of the order→disorder phase transformation in the alloys were determined.