The results of studying the elemental composition, structure, and physical properties of the copper electroerosion powder material fabricated by electroerosion dispersing (EED) in kerosene from rejects of copper wire of the electrotechnical grade are presented. An original home-made installation (RF Patent No. 2449859) was used for EED of conducting materials. It is established using an Analysette 22 NanoTec laser analyzer that the average size of the powder particle is 33,56 μm. The electron probe microanalysis showed that the content of main elements in powder is 79,5 % Cu, 17,7 % C and 2,0 % O. The results of electron microscopy of studied powder showed that it is constituted by regularly shaped (spherical or elliptical), irregularly shaped (conglomerates) particles, and fragmentary-shaped particles.

Peculiarities of fabrication of ceramic porous and dense composite materials based on compounds of the Si–C–O–N system with the participation of chemical reactions and formation of new phases are discussed. An attempt to analyze the relatively new technologies in terms developed in earlier works on reaction sintering of silicon nitride, carbide, and oxynitride is undertaken. It is shown that the approach to reaction sintering, which includes the selection of promising reaction systems allowing for bulk effect of reactions occurring in the course of material fabrication can be extended to the case of obtaining porous and highly porous materials. In contrast to the case of fabrication of reaction dense materials, where systems with positive bulk effects are used, the reaction systems with negative bulk effects can be used when fabricating highly porous materials.

Composites Al/Al2O3 (lamellar cermet matrix)–filling agent (discrete metallic filaments, duralumin chips, graphite particles, fused corundum grains, kaolin filaments, and technical alumina spherolites) are fabricated. Industrially produced PAP-2 aluminum powder, which consists of scaled particles with stearin coating (specific surface of the powder is 4,1322 m2/g, its particle sizes vary from 0,03 to 10 μm), was used to form the lamellar cermet matrix. In order to form the composites, the following production operations were used: heat treatment of PAP-2 powder in air to burn-out stearin from the particle surface and substitute it by alumina film, mixing the formed powder product with the filling agent, pressing, and reaction sintering the powder billets in a filtration burning mode in air. A new approach based on the chemical reaction of stearin saponification is proposed to fabricate the Al/Al2O3 composite. In this reaction, stearin on the surface of aluminum particles reacts with caustic soda resulted from the hydrolysis of diluted liquid glass introduced into initial powder. The reaction products (sodium stearate and glycerin) decompose during subsequent heat treatment in air with the formation of coke residue on the particle surface. Physicochemical properties of composites were determined using standard and generally accepted procedures.

Granules 45–315 μm in size are fabricated from powers of copper, its oxide, as well as aluminum and graphite by mechanical alloying in the attritor in air medium. Their structure represents a copper base with the grain size of 150–300 nm bordered by inclusions of the γ-Al2O3 phase 30–60 nm in size and small amounts of the Cu–Al2O3 phase and carbon are arranged. Microhardness of granules is in limits of 1500–2100 MPa. The samples of composite materials with the content of granules of 30, 50, and 70 wt.% are prepared by double compaction–sintering of a mixture of copper powder and mechanically alloyed granules. Their mechanical properties, electrical conductivity, and structure are investigated depending on the sintering temperature and amount of granules. Depending on the content of granules, properties of materials sintered at 900 °C, vary in the following limits: electrical conductivity is 55–70 % of electrical conductivity of copper of brand M1, hardness 60–93 HB, and tensile yield strength is 150–230 MPa. The strength and hardness increase with an increase in the weight fraction of granules, while electrical conductivity decreases. The structure of the material containing 30 % granules represents a copper matrix with granule-based inclusions, microhardness of which is 1150– 1700 MPa. A skeleton filled with a copper phase is formed in the samples containing 70 % granules. Hardness of the material with a weight fraction of granules of 50 % decreases less than by 15 % after annealing at 900 °C for 120 min.

Specific surface and porous structure of carbon fibers based on viscose produced by the Krasnoyarsk Plant of Chemical Fibers are investigated by low-temperature nitrogen absorption using an ASAP 2020 device. The dependence of their specific surface and character of the pore-size distribution on the modes of gas-phase activation in the carbon dioxide stream at 900°C is shown. It is established that the adsorption surface of carbon fibers can grow from 0,3 to 1900 m2/g in the course of activation. It is revealed that an increase in the activation time leads to an increase in the specific surface of fibers due to the appearance of numerous new micropores and development of the microporous structure.

The results of studying microstructure and hardness of surface layers of nickel alloy welded on titanium α + β alloy using fiber laser after their combined hardening under the effect of laser radiation are presented. Laser cladding makes it possible to form coatings with high hardness and quenching structures in surface layers of titanium alloy. Hardness of welded metal after the high-speed cooling from the melt temperature on the titanium substrate surface is larger than the density of martensite alloy formed in the titanium alloy after quenching.

The influence of mechanical treatment on the structure and phase composition of Ti–10%Ca3(PO4)2 powder mixtures is investigated. The Ti–Ti3P–CaO ceramic electrode materials with a high uniformity of components and residual porosity of 5–7% are fabricated according to the pressing and vacuum sintering technology. The erosion ability of the Ti–Ti3P–CaO metal–ceramic electrode under the pulsed electric-discharge machining of titanium substrates is investigated and compared with the TiC0,5–Ti3POx–CaO electrodes fabricated by self-propagating high-temperature synthesis. Coatings fabricated when using Ti–Ti3P–CaO and TiC0,5–Ti3POx–CaO electrodes are characterized by high continuity, thickness up to 20 μm, microhardness up to 3,6 GPa, roughness to 3,3–4,6 μm, and the presence and uniform distribution of calcium and phosphorus bioactive elements.

The deposition kinetics of electrospark coatings on EP718-ID heatproof nickel alloy is investigated using three compositions of SHS electrodes of the Cr–Al–Si–B system. The optimal frequency–energy deposition mode (Е = 0,048 J, I = 120 A, f = 3200 Hz, and τ = = 20 μs), which is characterized by a minimal electrode erosion with the satisfactory coating deposition rate, is established. Complex investigations into the structure, phase composition, and properties of coatings are performed. It is shown that electrospark coatings formed by Cr–Al–Si–B electrodes noticeably increase hardness, heat resistance, and wear resistance of EP718-ID nickel alloy and can be recommended to protect the surface of important parts and units made of nickel alloys.