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Comprehensive studies of the physical and mechanical properties and structure of VT1-0 titanium samples processed by selective laser melting have been carried out. High strength characteristics (the ultimate tensile strength of 820 MPa, the yield strength of 710 MPa) have been achieved. These exceed by 2 times the values for this material produced using conventional technology. The formation of the martensitic α'-phase, obtained due to the high crystallization rates realized in selective laser melting process, is the reason for the increase in the mechanical characteristics of titanium VT1-0. Mechanical characteristics of titanium VT1-0 subjected to high-temperature annealing demonstrated a monotonous decrease in strength parameters by 15% and an increase in plastic characteristics by 30%. It is shown that the technology of selective laser melting makes it possible to solve the problem of improving the strength characteristics of unalloyed titanium to create a new class of medical devices. Keywords: unalloyed titanium, VT1-0, additive technology, selective laser melting, density, strength, plasticity, elastic modulus, microstructure, implants for surgery.

The features of spark plasma sintering of submicron Al2O3 powders with different contents (0, 0.5, 1.5, 5 vol.%) of β-SiC nanoparticles have been studied. The microstructure and hardness of Al2O3 + 5 vol.% SiC ceramics obtained by sintering Al2O3 powders with β-SiC particles of various types (nanoparticles, submicron particles, fibers) have been studied. Sintering was carried out at heating rates (Vh) from 10 to 700oC/min. The sintering process of Al2O3 + SiC ceramics with low heating rates (V_h=10-50oC/min) has a complex three-stage character, with a flat area in the temperature range of 1200-1300oC. At high heating rates (V_h>250oC/min), the usual three-stage character of sintering is observed. The analysis of temperature dependences of compaction was carried out using the Young-Cutler model; It was found that the kinetics of powder sintering is limited by the intensity of grain boundary diffusion. It is shown that the dependence of the hardness of Al2O3 + SiC ceramics on Vh has a nonmonotonic character, with a maximum. In the case of pure alumina, an increase in Vh leads to a monotonic decrease in hardness Keywords: Alumina, silicon carbide, density, diffusion, hardness.

The effect of an additive of 0.5 wt.% of zirconium oxide on the spark plasma sintering (SPS) kinetics of alumina powders has been studied. Ceramics were obtained by mixing alumina powders in a planetary mill with grinding media from stabilized zirconium oxide. The activation energy of SPS was estimated using the Young-Cutler model. It has been shown that the density and average grain size in ceramics obtained from submicron alumina powders are significantly affected by the nonequilibrium state of the interfaces formed as a result of the transformation of the amorphous phase present on the alumina powder particle surface. The grain size and density of ceramics obtained from fine powders are significantly affected by the coalescence of ZrO2 particles. Keywords: Alumina, zirconium oxide, spark plasma sintering, density, diffusion, activation energy.

With an increase of magnetic field up to 0.8 T and plasma currentto 400 kA, fast ion losses rate in the discharges with toroidal Alfveneigenmodes decreased in tokamak Globus-M2 comparing with Globus-M tokamakdischarges. Taking into account the data on the discharges with increasedmagnetic field and plasma current, the regression fit of neutral particleanalyzer flux drop in energy channel close to neutral beam energy onrelative eigenmode magnitude, the value of magnetic field and plasma currentwas analyzed. The power of flux drop dependence on TAE magnitude was foundto be ~0.5 and inverse proportional on the value of product of magneticfield and plasma current, which is highly likely is determined only byplasma current due to weak dependence on magnetic field. The resultobtained indicates that fast ion losses in Globus-M2, stimulated by toroidalAlfven eigenmodes are mostly determined by the shift of passing orbits tothe plasma edge. With the increase of plasma current and magnetic field,neutron flux drops arising in the moments of toroidal mode bursts have alsodecreased. Keywords: TAE, NPA, spherical tokamak, fast ion losses\