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This work focuses mainly on making and study steel conductors with inhomogeneous surface conductivity and its effect on material behavior under generation of high pulsed magnetic fields. Monotonically changing resistivity was realized by pack chromizing steel grades 30KhGSA and 40Kh which were treated at 1000°C in argon under different conditions. An approach to investigate the resistivity distribution across diffuse layer after steel chromizing is proposed and some results are presented. To achieve a discrete change in resistivity., a powder technology is proposed that involves the use of a base steel powder., e.g. ., 30KhGSA., and compositions based on it with chromium addition to form a layered structure. The results obtained on single layer samples made of powders are discussed.

The mode of dynamic plastic deformation of metal-matrix composites based on aluminum and titanium is realized by the method of multiple magnetic-pulse pressing of powders. To obtain a different degree of deformation, the height of the compacts or the multiplicity of the pressing were varied. The initial powders with the “metal core - strong shell” structure were obtained by the method of electric explosion of the corresponding wires, followed by passivation. It was found that as a result of plastic deformation, these shells are destroyed and their fragments uniformly strengthen the metal matrix. This effect is enhanced by additional heating of the powder to 400°C during pressing. This approach makes it possible to increase the microhardness of pure Al and Ti by a factor of 5 to 1.2 and 5.7 GPa, respectively. In this case, the electrical resistance of aluminum and the plasticity of titanium composites are comparable with the corresponding characteristics of pure metals.

Hardness, fracture strength, wear resistance, and ultimate bending strength of ceramics based on aluminum oxide irradiated with gamma rays (0.8 MeV) up to 2000 Mrad are studied. It is found that mechanical properties of ceramics in which corundum prevails deteriorate under irradiation. Most resistant to gamma irradiation is a ceramic consisting of equal volume fractions of Al2O3 and 2.5 mol % of Y2O3 in ZrO2 (2.5YSZ) solid solution. A different trend of change in the unit cell parameter of the corundum crystal lattice under increasing irradiation dose is detected: as the irradiation dose increases, the unit cell parameter of the corundum crystal lattice increases in ceramics including zirconium oxide (α-Al2O3 + 10% ZrO2) (ZTA10) and α-Al2O3 + 55% YSZ (ATZ50)), and vice versa, it decreases if there is no zirconium oxide in the composition (Al2O3, α-Al2O3 + 4% MgAl2O4 (AM1)).

The influence of low concentrations (1 mol %) of few co-dopants (Y2O3, La2O3, CeO2, Gd2O3, Er2O3, ZnO) on the structure and characteristic of 10 mol % scandia stabilized zirconia was studied. Sintering kinetics and thermal expansion coefficients of synthesized solid eletrolytes were determined. It was found that co-doping increased the conductivity of electrolytes at temperature below 550°C. However, at high temperatures, the introduction of co-dopants decreased the conductivity; moreover, this reduction was more severe the more the ionic radii of Zr4+ and co-dopant differ.

Bulk nanocrystalline composites produced by high-energy ball milling of nitrated iron powders followed by dynamic pressing are studied. Composites consist of three phases α-Fe + γ′-Fe4N + Φ, where the nature of the Φ phase is determined by the milling environment (nitrogen, heptane, or xylene). The microhardness of composites is 6–7 GPa at a density of 95–97%. Composites are characterized by a high corrosion resistance in chloride solutions.

Uniaxial magnetic-pulse compaction of nanosize powders is studied experimentally and theoretically. Experiments are carried out with powders based on aluminum oxide. The theoretical model of the process includes the consistent solution of equations describing the dynamics of the pulsed magnetic field as well as the dynamics of the mechanical system (movable parts of the press and the powder being compacted). The behavior of the powder is described using the phenomenological theory of a plastically compacted porous body. Direct comparison with experimental data makes it possible to determine all input parameters required for theoretical calculations. A wide range of pressing conditions is investigated and the effect of parameters such as the mass of the powder being compacted and the mass of the parts of the press being accelerated is analyzed. The conditions are determined for the most effective use of inertial properties of the press, which must result in high-density products of compacted powders.

An experimental and theoretical study of the process of the uniaxial magnetic pulse compaction of nanopowders is conducted. The experimentation is carried out using aluminum oxide powders. The developed theoretical model includes the integrated description of the pulse magnetic field and of the dynamics of the mechanical system (of the moving pressing tooling and of the densified powder). The powder constitutive behavior is considered in the framework of the phenomenological theory of plastic porous bodies with hardening. The direct experimental data input enables the introduction of all the parameters necessary for the theoretical calculations. Based on the developed model, the influence of a broad range of pressing conditions and parameters (the densified powder mass, the mass of the accelerated press equipment parts, specimen diameter, etc.) on the final specimen density and on the effectiveness of the magnetic pulse compaction is studied. The process conditions, under which the optimal inertia properties of the pressing device lead to the fabrication of high-density components, are determined.

Bulk Fe-TiC-Fe3C nanocomposites were fabricated by compaction of powders which were prepared by mechanical alloying of Fe (82 at %) and Ti (18 at %) in the media of toluene and vinyltriethoxysilane. The compacts were then annealed at 925°C. The structure and phase composition of the composites were investigated by X-ray diffraction, electron and atomic force microscopies, and Auger electron and X-ray photoelectron spectroscopies. It was shown that the use of organic liquids as a carbon source during mechanical alloying makes it possible to obtain materials with nanosized carbide inclusions uniformly distributed in the bulk material. Some combinations of the medium for mechanical alloying and milling time allow one to fabricate composites with high microhardness (12 GPa) and enhanced corrosion resistance.

X-ray diffraction, atomic-force microscopy, and density, microhardness, and coercive force measurements were used to study bulk iron-cementite nanocomposites obtained by different regimes of magnetic pulsed pressing of mechanically alloyed samples with a total carbon content ranging from 5 to 25 at. %.

The effect of the composition and density of ceramics on the electroconductivity of solid electrolytes Ce1 − xGdxO2 − δ(x = 0.09–0.31) with a submicron (0.1–0.3 µm) grain size, which are prepared from nanosized powders, is investigated. The powders are synthesized by two methods, specifically, by evaporation of a target with the aid of the radiation of a pulsed carbon dioxide laser and by a chemical method of burning. The samples of ceramics are prepared by magnetopulsed or quasi-isostatic (200–500 MPa) pressing and subsequent caking in air at a temperature of 1100–1300°C. It is established that the electroconductivity of the obtained solid electrolytes is higher and the effective activation energy for conduction is considerably lower as compared with analogous electrolytes with a micron grain size.

Metal matrix composites (MMCs) containing matrices with nanometer grain sizes have been produced from pure aluminum nano-powders (particle sizes 50-200 nm) with SiC reinforcement (particle sizes 3-10 {micro}m). The pure Al nano-powders were produced using an exploding wire technique. Dynamic loading using a magnetic impulse technique has been used to compact the MMC to high density. The dynamic compaction process results in excellent wetting of the SiC particles by the nanocrystalline Al powders, and the retention of a nano-crystalline grain size in the MMC. Microstructural analysis of the resulting MMC showed a highly uniform distribution of Sic particles with no visible defects or pores and the absence of deleterious phases (such as Al{sub 4}C{sub 3}) at the interfaces between the aluminum nano-grains and the SiC particles. The microstructures produced and the evolution of microstructure during dynamic compaction has also been studied using TEM and found to progress in three stages. These three stages are described.

Effect of the precursor approach, the method of nanosized powders pressing, and the sintering temperature of ceramic samples on the low-field magnetoresistance of nanosized La0.7Sr0.3MnO3 ceramics was studied.