The results of the investigation into the influence of the sintering mode, morphology, and chemical composition of aluminum powders (ASD-1 and PA-1 brands) as well as the content of alloying additive (Cr) on regularities of sintering, structure, and physicomechanical properties of powder bodies of the Al–Cr system with the chromium content of 2,5–20 at.% during liquid-phase sintering at temperatures of 700–900 °C are presented. The sintering mode providing the fabrication of powder bodies with the conservation of the initial form is established. It is found that the application of ASD-1 aluminum powder makes it possible to fabricate more dense briquettes almost overall the studied range of sintering temperatures and provides the better sinterability of compacts, which is explained by its higher chemical purity, dispersity, and spherical shape of grains. Alloy of the composition Al–(2,5÷7,5) at.% Cr sintered at 700°C showed the best physicomechanical characteristics among all studied samples.

Substances (K2Ta2O3F6, K3TaOF6, K2TaOF3, and KTaOF4) most suitable for the use as oxygen-containing additives in the sodiumthermal fabrication of finely dispersed tantalum powder are selected from the melts containing complex oxyfluoride compounds of tantalum based on thermodynamic and experimental investigations of reduction reactions of tantalum compounds with sodium. The application of mentioned compounds gives the opportunity to fabricate the tantalum powders with the specific surface at a level of 3–5 m2/g, which is higher by a factor of 8–10 compared with powders prepared under the same conditions upon reducing K2TaF7. It is shown that the prepared tantalum powders can be demanded as the initial material to create the capacitor powder with the charge of 70000–100000 μC/g.

Boron carbide is prepared by self-propagating high-temperature synthesis (SHS) in a range of compositions from 5 to 30 at.% carbon. The introduction of inert (MgO) and active (Mg(ClO4)2) additives leads to the variation in process parameters such as the temperature and combustion rate. It is established that depending on the synthesis conditions, the metrics of the unit cell of boron carbide is subjected to substantial variations. The degree of the effect of the SHS mode on the crystal structure increases with an increase in the carbon fraction in the boron carbide structure. The observed regularity is associated with the diversity of ordering of carbide atoms in nonstoichiometric boron carbide. No influence of the synthesis conditions is observed for the stoichiometric boron carbide, which is associated with the saturation of the structure with carbon. It is shown that the variation in the combustion temperature at SHS of boron carbide of the same composition leads to the variability of structural parameters reflecting the influence of the synthesis conditions on the crystal structure of the material.

Regularities of dissolution, phase formation, and structure formation in the course of the interaction of double carbides (Ti1–nMen
IV,V)C with Ni–25%Mo melt (t = 1450 °C, τ = 1 h, vacuum 10–1 Pa) are for the first time investigated by electron probe microanalysis and scanning electron microscopy. The role of each alloying metal in the formation of the composition and microstructure of studied compositions is revealed. It is established that alloying Group IV metals (Zr and Hf) almost do not enter the composition of the formed K-phase (carbide Ti1–nMonCх); therefore, its composition is independent of their concentration in double carbide. In contrast with zirconium and hafnium, alloying metals of Group V (V and Nb) actively participate in the formation of the K-phase; however, the dependences of the composition of the K-phase and metal matrix on the vanadium and niobium content in initial carbide have the opposite character in this case. The explanation of the causes of these distinctions is proposed.

Macrostructure of nickel foam with porosity of 20, 30, 45, and 60 ppi is investigated by X-ray tomography at voltage U = 300 kV, current I = 300 mA, and exposure time texp = 354 ms is investigated; the number of frames was 2500. It is established that actual parameters of pores deviate from theoretical ones. It is shown that the higher porosity is, the more uniform the pore-size distribution is. The X-ray tomography makes it possible to evaluate such characteristic as the thickness of the wall between the pores, which was not taken into account previously. It is revealed that the uniformity of the wall thickness with respect to sizes decreases as the sample porosity increases. These results make it possible to recommend the X-ray tomography as the method for the investigation and monitoring the foam materials and powders in various sintered materials, and the acquired data can be used to create actual three-dimensional models.

The results of studying the microstructure and microhardness of Ni-resist cast iron ChN16D7GKh after laser melt injection by means of introducing titanium into the melt are presented. The treatment was performed using a fiber laser with a beam focused into a spot 0,2 mm in diameter with the radiation power of 1 kW and motion velocity of the laser beam of 10–40 mm/s. Titanium is dissolved in the cast-iron melt, and TiC particles are formed in the structure in  he course of cooling. The coefficient of using the titanium powder increases as the size of the fusion zone increases and reaches 50 % in the best case. A modified layer has a composite structure with a metallic matrix and comparatively uniform distribution of titanium carbide particles. Microhardness of the modified zone is 600–700 HV. Its further growth is suppressed by the partial removal of carbon from the melt zone in the composition of red fume isolated in the process course. Therefore, the Laves phase (TiFe2) is formed instead of increasing the TiC content upon increasing the titanium supply. The experimental data on the regularities of the weight loss of the samples caused by substance removal from the melt zone depending on laser fusion parameters are presented.

Coatings TiCaPCON–Ag with the silver content of 1,0 and 2,5 at.% were obtained by magnetron sputtering. Two types of substrates with different roughness were used for their deposition, notably, polished titanium (average roughness Ra = 20 nm) and the surface modified by pulsed electric-spark treatment (Ra = 8 μm). Structural studies showed that the introduction of silver into the composition of coatings leads to the formation of nanoparticles 5–10 nm in size on their surface. The yield kinetics of silver from coatings into the physiological solution is investigated by mass spectrometry with inductively coupled plasma. It is shown that the yield of silver ions into the biological medium can be controlled due to varying the substrate surface roughness.

The influence of the tin content on the structure and hardness of the Sn–Cu–Co and Sn–Cu–Co–W alloys, which are applied as bonds of diamond-abrasive tools, is investigated. Bonds were prepared by the compositional brazing: powder components were mixed with organic bond and deposited on a steel base. Sintering was performed at 820–1100 °C. The structure of metallic binders was investigated by the X-ray diffraction and electron probe microanalyses. In addition, microhardness of structural components and macrohardness of bonds were measured. It is established that the hardness of tin bonds linearly increases as the tin content increases due to an increase in amount of solid intermetallic phases in their structure. The optimal tin content, which provides high hardness (96–98 HRB) and absence of low-melting high-tin intermetallic compounds in the bond structure, is determined for the Sn–Cu–Co–W bonds.

The influence of regimes of mechanical activation on geometric, energetic, and chemical parameters of activation of alumina used as a component of dressing coatings. The studies made it possible to determine the most rational treatment modes, notably, using an AGO-2 planetary-centrifugal mill: activation time is 20 min at material : balls ratio of 1 : 3. The dependences of the average particle size, the total surface, and variation in their phase composition on activation conditions are established. It is shown that the average particle size of alumina particles decreases from 3,2 to 1,6 μm with an increase in their total surface from 31·103 to 61·103 cm2/cm3. X-ray lines also broaden without decreasing their intensity; consequently, now new phases are formed in the course of activation during the decomposition of gibbsite γ-Al2O3. Two fractions are present in mechanically activated alumina, notably, initial α-Al2O3 having the crystallite size of the order of 1 μm (which corresponds to its very narrow lines in X-ray diffraction patterns of initial alumina) and finely dispersed α-Al2O3 with crystallite sizes approximately of 0,1 μm (which usually corresponds to the initial broadening stage of the lines of a new phase), which is formed due to the decomposition of gibbsite.