The refining and modifying influence of calcium, barium, and strontium carbonates on the microstructure and mechanical properties of brass billets is investigated. The possibility of applying dispersed carbonates in refining and modifying mixtures is confirmed by thermodynamic calculations. It is shown that the introduction of these compounds in the brass composition improves the mechanical properties of casts. The composition of preparations is chosen experimentally using the optimization methods. A high efficiency of the carbonate-based refining mixture with a modifying effect is confirmed by industrial tests.

Low-basic Cybber anionites with various functional groups and matrix type are tested for recovery of rhenium from multicomponent sulfuric acid solutions. It is established that anionite SX002 manifests an increased capacity during the sorption from solutions with a low Re content, while anionite ALX220 is applicable to recover Re at its high concentrations in the solution. The ionic background of the industrial solution affects the capacity of sorbents with respect to rhenium. When studying the kinetic characteristics, it is revealed that sorption processes on ionites are limited by the internal diffusion. The tests of ionites as applied to Cr-containing solutions indicate the possibility of using anionites ALX220 and SX002 to recover rhenium.

A complex manufacturing method of the billets from the material based on high-boron nickel aluminide is proposed. The method includes manufacturing the semifinished alloy products using a combined method of self-propagating high-temperature synthesis and centrifugal casting from oxide feedstock and subsequent vacuum induction remelting with introducing Al-based foundry alloys containing nanosized ZrO2 and modifying the structure. The evolution of the microstructure and phase composition is investigated at all production stages. A cast ZrO2-modified cylindrical billet, which possesses high purity in regards to gas impurities (O – 0,005 wt.% and N – 0,0001 wt.%) and is suitable for the further production of powders by the plasma rotating electrode process, is fabricated according to the proposed technology.

Closed analytical solutions of a plane strain problem for contact stresses in zones with variable friction forces for upsetting the strip made of ideal rigid-plastic material are derived. It is established that the use of the Mises exact plasticity condition for the slip zone instead of the approximate one written in principal stresses allowing for the Coulomb friction law leads to an essential (by a factor of 2–4 at f > 0,2) increase in the calculated slip zone length. To match the theoretical results with the experimental ones, a new method for calculating the contact stresses is proposed, in which their distributions in the slip and stagnation zones are derived from the solution of the plane strain problem using a parabolic approximation of the plasticity condition. The sizes of slip and stagnation zones are found depending on the characteristics of contact friction and conditions of appearance of the peaks near the strip end in the normal stress diagram are determined. The possibility of occurrence of retardation zones under tangent contact stresses lower than the yield point under simple shear τs are determined. Formulas for determining the upsetting force are refined.

The data of experimental studies on determining the mechanical properties of long-length deformed semifinished products in a form 
of bars and wire made of alloys of aluminum with rare-earth metals, which are fabricated using the combined treatment methods, are presented. The application of the combined technology of casting, rolling, and pressing makes it possible to increase the strength of hot-extruded rod by 15–20 % on average compared with combined rolling–extruding the cast billet formed in an electromagnetic crystallizer. It is also shown that a decrease in the REM content in the alloy leads to the strength reduction and an increase in plastic characteristics. Herewith, it is possible to control the level of physicomechanical characteristics of the final product varying the summary deformation ratio during drawing and applying annealing.

Possibilities of producing small-diameter tubes made of titanium alloys in a size range from 20 to 80 mm are considered. An experiment on piercing the billets made of commercially pure titanium VT1-0 with its further reduction using a screw rolling mill is performed. Experimental results that confirm the performing possibility of the manufacturing technology of hot-rolled seamless thick-wall tubes smaller than 73 mm in diameter using screw rolling mills are presented.

The influence of the density of titanium briquettes formed from titanium sponge of TG-100 brand and the presence of hydrogen in them on the force of direct briquette compacting at 600 °C, density, and mechanical properties of pressed rods is investigated experimentally. The results show that the smaller compacting force is required while the density and plasticity of compacted rods evaluated at
t = 600 °C increase.

Rheological properties of polycrystalline iridium of I 99.9 brand are investigated in order to construct the dependence of deformation resistance on studied factors (strain ratio, rate, and temperature). The tests of cylindrical samples made of iridium are performed using a cam plastometer in temperature range t = 900÷1400 °C at strain rates ξ = 0,2 and 20 s–1 as well as at t = 800÷1400 °C and ξ = 2 s–1 using the upsetting method at a strain rate up to 0,8. The results of investigations can be used to develop the pressure treatment of iridium wares at large plastic strains and in a broad range of thermomechanical parameters.

Amorphous thin-film Si–B–C–(N) coatings are fabricated by magnetron sputtering of sintered Si–B–C targets. The coating structure is investigated using X-ray phase analysis, scanning and transmission electron microscopy, scanning probe microscopy, glow-discharge optical emission spectroscopy, and Raman spectroscopy. Mechanical and tribological properties of coatings are determined using nanoindentation, scratch testing, and pin-on-disc testing. The oxidation resistance of coatings is investigated in a temperature range of 1200–1600 °C. It is established that coatings of the optimal composition possess hardness of 20 GPa, elasticity modulus of 210 GPa, elastic recovery of 53 %, friction coefficient of 0,6 against cemented carbide ball, and oxidation resistance above 1200 °C due to the formation of the SiO2-based protective film on their surface. Coatings deposited by sputtering the target of the Si70B25C composition in Ar + 15%N2 medium showed oxidation resistance both under long-term heating at t = 1200 °C for 12 h and short-term heating at temperatures of 1400, 1500, and 1600 °C.

Alloy powder of the Ti–47Al–2Nb–2Cr composition (at.%) with the structure of TiAl (60 wt.%) and Ti3Al (40 wt.%) is prepared by the calcium-hydride method. The mode of the calcium-hydride synthesis is optimized for the Ti–50Al (at.%) model alloy. It is established that the reduction temperature should be no lower than 1100 °C, while the excess of the CaH2 reducing agent should be no lower than 15 wt.%. The main physicochemical and manufacturing properties of the synthesized Ti–47Al–2Nb–2Cr powder alloy, which provide the formation of dense compacts during its subsequent consolidation processes, are determined using modern analytical methods.

The influence of parameters of mechanical activation (MA) on the structure and phase composition of the Ni–Al reaction mixtures as well as the products that are formed from them during the subsequent self-propagating high-temperature synthesis (SHS) is investigated using optical and electron microscopy, X-ray structural analysis, electron probe microanalysis, and laser diffraction. Optimal MA modes of reaction mixtures and optimal synthesis conditions of porous cakes are determined. Special functional additives of Al2O3, BN, and WC powders, which increase the cake porosity and facilitate the subsequent grinding, are selected; and their amount is determined. It is revealed that boron nitride and tungsten carbide additives most efficiently promote the destruction of NiAl particles. Submicron powders with the NiAl-based nanoblock structure are prepared.