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Cox-CrNbWMoAlC cast high-temperature materials were prepared from mixtures containing Co3O4/Cr2O3/Nb2O5/WO3/MoO3/Al/C and additive of 5% Al2O3 by centrifugal self-propagating high-temperature synthesis (SHS). As Co3O4 + Al was added, the burning velocity grew by five times. CrNbWMoAlC alloy was shown to have a multiphase structure consisting of NbC, Cr23C6, and Cr0.53Mo0.14Al0.33. Introduction of Co3O4 and Al was found to yield Cox-CrNbWMoAlC alloy with a dendritic structure containing Co and NbC phases as a basis.

A relatively new approach to obtaining metal materials containing several principal elements in equiatomic concentrations which look promising for replacing commercially used alloys is proposed. Such materials are called high-entropy alloys (HEAs). Studies show that HEAs tend to form a simple solid-solution structure and can also contain ordered intermetallic phases. Such a method of forming metal materials can be regarded as a background for producing new HEAs with elevated performance characteristics. Most studies focus on the relationship between microstructure and measured properties; significantly less attention is paid to studying and developing new effective methods for creating HEAs. In this paper, we study the possibility of obtaining CoCrFeNiMn–(X) HEAs by centrifugal metallothermic SHS. Chemical and technological modes of modifying cast CoCrFeNiMn alloy during synthesis (in situ) by introducing alloying components into the starting exothermic compositions are tested for the first time. The microstructure and phase composition of NiCrCoFeMn alloys synthesized from mixtures containing Ti–Si–B(C) or Al are characterized. The microstructure of CoCrFeNiMn–(Ti–Si–B(C)) HEAs is found to consist of an HEA-based matrix and new structural inclusions of carbides and borides of titanium. High-Al CoCrFeNiMn–Al HEAs are represented by a composite structure containing NiAl as a basis and dispersion nanoprecipitates (~100 nm) of a Cr- and Fe-based solid solution.

This paper presents a study of direct conversion of chemical energy into electrical energy during the combustion of a (80Zr + 20CuO)–(LiF + CaF2 + MgF2)–(15Zr + 85CuO) thin three-layer condensed energy system, which is a high-temperature galvanic cell. It is determined that this cell during combustion generates an electric signal with an amplitude of 1.6 V and a half-width of 15 s. Its formation mechanism is proposed. A time-resolving X-ray diffraction method is used to identify the phases formed.

Metallothermic SHS in conditions of artificial gravity was numerically modelled for the 3NiO + 2Al → Al2O3 + 3Ni reaction taken as an example. The process was assumed to include (a) high-temperature combustion reaction yielding liquid products, (b) their gravity-assisted separation, and (c) cooling down. In our ‘throughout’ mathematical model, a three-component emulsion—gas, metal, and ceramics—with individual translational velocities and temperatures was considered. Our model may expectedly extend the range of control means for SHS reactions in extreme conditions.

—Regularities of the formation of ultrafine-grained (UFG) and submicrocrystalline (SMC) structures in new nickel-free low-modulus Ti–Nb–Mo–Zr titanium β alloys under the action of plastic deformation have been studied. Temperature–time ranges of the development of dynamic recrystallization processes under the simultaneous action of temperature and plastic deformation are determined. A type-II recrystallization diagram of the Ti–28Nb–8Mo–12Zr alloy is constructed and analyzed. It is shown using scanning electron microscopy and the electron backscatter diffraction method that the UFG structure with an average grain size of no more than 7 μm and high fraction of high-angle grain boundaries is formed in the investigated alloys as a result of longitudinal rolling, followed by annealing for quenching. It is found that the formation of the UFG structure leads to a significant increase in the strength and plastic characteristics of these alloys. The regularities of the formation of UFG and SMC structures in titanium β alloys Ti–28Nb–8Mo–12Zr and industrial VT30 under the action of plastic deformation by the helical rolling method are studied. It is shown that the helical rolling of the VT30 alloy leads to the formation of the homogeneous UFG state as opposed to the Ti–28Nb–8Mo–12Zr alloy, where this method causes structure softening with micropores and microcracks formed in the central region. It is possible to form a nanostructured state with an average grain size of about 100 nm in Ti–Nb–Mo–Zr titanium β alloys using the high-pressure torsion method.

The possibility of obtaining a composite material based on titanium and chromium borides with a nickel binder by metallothermic SHS was considered. In the experiments, calcium chromates CaCrO4 and CaCr2O7 were used as the chromium-containing component of green mixtures. Thermodynamic calculations showed that the combustion temperature of the mixture based on calcium dichromate (CaCr2O7) exceeded by 200°C the combustion temperature of the mixture based on calcium chromate (CaCrO4). The use of calcium dichromate allowed us to expand the limits of combustion and phase separation of the mixture, as well as to increase the yield of the target product. XRD analysis and SEM/EDS data showed that the obtained composite material contains triple boride Ni20AlB14 as a basis and chromium and titanium borides and titanium–chromium boride, which are uniformly distributed over the material.

A method of preparation of titanium materials with a porous surface layer by hydrostatic pressing and subsequent high-temperature sintering with use of a pore former as a temporary space holder was proposed. Comparative studies of the structure and properties of titanium materials with a porous surface layer fabricated in a new way and by the classical method of powder metallurgy (uniaxial pressing and high-temperature sintering) were carried out. It was shown that this method makes it possible to obtain porous titanium samples with preset parameters of pore space (volume fraction and pore size) and high mechanical properties. An experimental sample of an endoprosthesis element (acetabular cup) was fabricated using the proposed method.

A Co–Cr–Mo alloy with homogenous ultrafine-grained structure prepared by combined use of metallothermic SHS and subsequent thermomechanical treatment (TMT) was characterized by SEM and XRD and the processing conditions were optimized.

The elastoplastic properties (elastic modulus, amplitude-independent damping ratio, microplastic flow stress) of a Ti-26Nb-7Mo-12Zr titanium β alloy are determined using an acoustic resonance method. The effect of the strain during thermomechanical treatment on the structural features of the micro-crystalline alloy and, hence, its elastoplastic properties is analyzed.

The calculation of the choice of a new low modulus titanium β alloy was described. The investigations of the structure and properties (mechanical, tribological and corrosive) of low modulus titanium β alloy Ti–26Nb–7Mo–12Zr after mechanical–thermal processing were carried out. An analysis of the results of experimental research showed that the formation of homogeneous fine grained structure by sheet rolling with subsequent annealing before quenching leads to decreased elastic modulus, increased plasticity and wear resistance. Therefore, new titanium β alloy designed in the present study, Ti–26Nb–7Mo–12Zr, is expected to have good properties as biomaterial.

The structure and phase composition of a VKNA-25 alloy based on the Ni3Al intermetallic compound, produced by directional solidification, and alloyed with rare-earth metals are studied in the following two states: after annealing at 1100°C and after creep at 1100°C.

One of the complications of specific antiblastoma therapy in the patients presenting with malignant neoplasms is the suppressed functional activity of blood neutrophil granulocytes. The results of clinical and experimental investigations suggest the enhanced enzymatic activity of neutrophils and lymphocytes under effect of ultrahigh-frequency electromagnetic radiation (UHF EMR). Our study has demonstrated that UHF EMR with a frequency selected on an individual basis in the range from 59 to 63 GHz exerts the protective action on the function and metabolism of blood neutrophils exposed to the damaging action of gamma-radiation in the patients presenting with lung cancer. Moreover, it allows the severity of local and systemic complications of specific antiblastoma chemo- and radiotherapy in these patients to be reduced.

This study included 188 patients presenting with pathology of the biliary system, such as dyskinesia of bile ducts, chronic non-calculous cholecystitis (CCC), and dysfunction of the bile system. The objective of the work was to develop complexes of intensive non-medicamental rehabilitative treatment for the correction of the adaptive potential of the organism in the springtime (March-May). It was shown that the efficacy of therapy during this period can be improved by modulation of the complex structure. New treatment modalities were proposed taking into consideration specific changes of clinical characteristics in different phases of the circumannual cycle and curative effects of various therapeutic factors that increase the adaptive potential of the organism. These complexes allowed both the efficiency and the tolerability of the treatment to be improved. It is concluded that the use of corrected complexes of intensive therapy in springtime (March-May) permits to reduce the duration of therapy by 5-6 days from the usual 21-24 days using the traditional approach.

Low-modulus titanium β-alloy Ti-26Nb-7Mo-12Zr for medical application, composed of nontoxic elements V and Al was considered. The influence of deformation in combination with heat treatment on the structure and properties of β-alloys such as elastic modulus, yield strength and tensile strength, ductility was investigated.