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In this article, the coatings of ZrB2-xMoSi2-Y2O3-yAl (x = 24, 35, 45 wt %; y = 10, 15, 20 wt %) were applied to the surface of a carbon/carbon composite to protect against high-temperature oxidation using a multi-chamber detonation accelerator. The kinetic analysis of the formation processes of a glass-forming layer during the oxidation of the initial components of the system ZrB2-MoSi2-Y2O3-Al in an air atmosphere at a temperature of 1400 °C was carried out and the kinetically significant stages of the heterogeneous reaction were determined. It is shown that the speed and density of the formation of a glassy matrix can be adjusted by fine-tuning the ratio of components in the initial powder.

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Composite ZrB 2 -MoSi 2 coating modified by Y 2 O 3 and Al was prepared by a new multi-chamber detonation accelerator (MCDS) on carbon/carbon composites. Postdeposition heat treatment of the samples at 1500 • C for 1 and 6 h was carried out in air. The effect of heat treatment on the microstructure and phase composition of the ZrB 2 -MoSi 2 coating was investigated by scanning electron microscopy and X-ray diffraction phase analysis. The as-sprayed coating presented as a dense lamellar structure, composed of m-ZrO 2 , t-ZrO 2 , some hexagonal ZrB 2 , and cubic Al phases. The m-ZrO 2 , c-ZrO 2 , and h-(α-Al 2 O 3 ) formed at 1500 • C. The coatings after heat treatment (1 and 6 h) exhibited a structure without cracks. The porosity (~1%) of the coating did not change after heat treatment. Thin, continuous, silica-rich film covered the surfaces of ZrO 2 and Al 2 O 3 particles, and could have played a role during heat treatment by acting as a grain lubricant for particle rearrangement.

Electrically conductive amorphous carbon nitride (a-CN) coatings were deposited onto various substrates by pulsed vacuum-arc sputtering of a graphite cathode with simultaneous irradiation of the substrate with nitrogen ions. Deposition temperature was less than 60 • C. We investigated the effect of vacuum annealing at a temperature of 600 • С on the elemental composition, structure, electrical and optical properties of the obtained films. It was found that the elemental composition of the coating practically does not change over the thickness of the coating after annealing, while the remaining characteristics change significantly. Of particular interest is the correlation between the change in the nanostructure of the coating and the electrical properties of the coating. An explanation of the mechanisms for changing the properties of the coating after annealing is proposed.

The ZrB2-ZrO2-MoSi2-Al coating was prepared by a new multi-chamber detonation accelerator on carbon/carbon (C/C) composites without adhesion sublayer. The microstructure of the coating showed the laying characteristics of completely molten and partially molten areas had as lamellar-like structure. The coating was dense, homogeneous, and well connected with C/C composite substrate without sublayer. Void content in coating is 0.5±0.05% as determined by image analysis.

Thin films of predominantly amorphous n-type SiC were prepared by non-reactive magnetron sputtering in an Ar atmosphere. A previously synthesized SiC was used as a solidstate target. Deposition was carried out on a cold substrate of ptype Si (100) with a resistivity of 2 Vcm. The Raman spectrum shows a dominant band at 982 cm À1 , i.e., in the spectral region characteristic for SiC. It was found that the root mean square roughness varies from about 0.3 nm to 9.0 nm when the film thickness changes from about 2 nm to 56 nm, respectively. Transmission electron microscopy studies showed that SiC thin films consist predominantly of an amorphous phase with inclusions of very fine nanocrystallites. A heterostructure consisting of a p-type Si (100) and a layer of predominantly amorphous n-type SiC was fabricated and studied. The investigation of its electrical and photoelectric properties shows that the entire space charge region is located in Si. This is in addition confirmed by the spectral dependence of the p-Si/ n-SiC photosensitivity. The barrier height at the p-Si/n-SiC interface estimated from dark I-V characteristics is of the order of 0.9-1.0 eV. Load I-V characteristics of p-Si/n-SiC-nanolayer solar cells demonstrate under standard AM1.5 illumination conditions a conversion efficiency of 7.22%.

It is shown that at low negative bias potential applied to the substrate during the deposition (Ub is less than 150 V), a two-phase state with the preferred orientation of crystallites can be reached for the multilayer coatings with the layer thickness of 50 nm. This causes high hardness (up to 59 GPa) and high adhesion strength at the same time (critical load reaches 124.9 N). Low wear resistance of the coatings in contact with the counterbody of Al2O3 is observed.