Search

The results of a search for correlations between the crystal-geometry parameters and structural-phase states in the alloys based on Ag–Me (Me = Co, Rh, Ir, Ni, Pd, Pt, Cu, Au) are presented. The limits of numerical values of the crystal-geometry and thermodynamic factors are identified, within which inorganic regions of solid solutions are formed in the state diagrams of binary systems or monotectic reactions take place in the systems due to a limited solubility of the system components in liquid states. It is shown that an approach relying on the analysis of state diagrams, including the crystal-geometry and thermodynamic factors of the alloy-forming elements into consideration, is promising in searching for common patterns of structural-phase states in the Ag-based alloys; it is found out that an Ag–Pt system is the most attractive binary system in this respect. A slight deviation of the experimental concentration dependences of the atomic volume in the solid solutions of the Ag–Pd and Ag–Au systems from the Zen relation is observed in intermetallic compounds in the alloys of the Ag–Pt system.

The feasibility of producing protective radio-absorbing shielding materials on the basis of differently shaped surfaces with nanostructured coatings is investigated. Combinations of special nanostructured materials and technical solutions for the shape of the absorbing surface were tested, in order to create efficient nanocoatings. It is shown that the coatings of interest that meet the requirements of low reflection and high attenuation of transmitted radiation combined with low coating thickness can be developed, using corrugated surfaces. Corrugated chicken egg-packing cell samples with nanostructured carbon coatings were examined and found to allow for effective shielding of electromagnetic radiation and to exhibit minimum reflection coefficients as compared to construction materials.

The effect of the nature of carbon nanofillers on the structure-sensitive characteristics of resistive composites with polyurethane binders is investigated. The influence of the size, shape, concentration of carbon nanofibers (K-163 channel black, GE-3 graphite element, C-1 colloid graphite) and the method of their introduction into the binder on the formation of an electrically conductive mesh in the structure of the composite is identified. It is experimentally found that an introduction of C-1 colloid graphite ensures optimal parameters of specific volume resistivity, hardness, and adhesion strength, as well as low values of the percolation threshold.

Results of investigations of the reflection and transmission coefficients of flat specimens made from multifunctional composite polyurethane-based materials with fillers of three types: channel black K-163, colloidal graphite preparation С-1, and elemental graphite GE-3 are presented in teraherz frequency range. The calculated complex dielectric permittivity in this frequency range is presented. It is demonstrated that specimens with carbon filler content of 10 mass% and higher effectively reflect teraherz electromagnetic radiation, and specimens with filler content of 5 mass%, can be used as radio absorbing coatings. The feasibility of application of these materials for heating elements of press plates is analyzed.

Thermostability of resistive materials based on polyurethane used as heat-liberating elements in the design of heating elements of thermoactive formworks is investigated. The application of polyurethane as a binder provides solid contact of polymer molecules with nanodimensional carbon fillers and their uniform distribution in a composite material. The influence of thermal treatment and dispersed fillers on the stability of electrophysical and thermophysical properties of carbon-filled polyurethane coatings is established.