On the example of a single optimization principle, the role of technological trends in the technologies used in improving the quality of the final product in the conditions of real ceramic production is considered. The dependence of the level of homogeneity of the final microstructure of a polycrystalline material on the probability of achieving the requirements imposed by the unified optimization principle for such technological stages as synthesis, molding of workpieces and their sintering is shown. On the example of nuclear fuel elements, ways of improving the quality and profitability of the production of ceramic products intended for operation in extreme conditions are considered.
The efficiency and feasibility of using fractal methods to study the surface structure of ceramic materials have been investigated. It was found that the fractal formalism can be used as a means of studying the evolution of surface morphology and that multifractal parameters make it possible to judge the degree of homogeneity of the surface structure and the conditions of its formation.
Highly efficient wall ceramics based on expanded perlite, flask and ground glass have been obtained. The possibility of producing solid ceramic bricks (average density 925 kg / m 3 and compressive strength 13.5 MPa) for low-rise construction has been shown
A three-component ceramic material based on the ZrO2 - SrTiO3 - BiScO3 system has been obtained, its phase composition, microstructure features have been established, and the temperature dependence of the electrical conductivity has been studied. It was found that at room temperature the material consists of a cubic phase with a space group of symmetry Fm3m, corresponding to the cubic modification of zirconium dioxide, and a solid solution consisting of a nonpolar cubic phase with Pm3m symmetry and a polar tetragonal phase with P4mm symmetry and characteristic of the two-component system ZrO 2 ? SrTiO 3 ? BiScO 3 . The presence of these phases is confirmed by the results of studying the microstructure and elemental composition of the samples by scanning electron microscopy. It was found that above a temperature of ~ 750 K, the specific electrical conductivity of the samples under study increases significantly
The cybernetic equation of the complex dielectric constant of the condensed sample is considered. The results of computer simulation of long-wavelength optical spectra of pure crystalline oxides, as well as the resulting spectral dependences of the electronic properties of the sample under study, are presented.
The obtained ceramic material of the composition 0.5SrTiO 3 ? 0.5Y 0.1 Zr 0.9 O 2 and the features of its dielectric properties and electrical conductivity have been established. It was found that the material consists of two phases: the cubic Fm phase of zirconium dioxide stabilized by yttrium and the tetragonal I4 / mcm phase of the solid solution SrTi 1 - x Zr x O 3 . At T> 500 K, dielectric relaxation with an activation energy of the process ~ 1.1 eV, which is characteristic of titanium-containing compounds with a perovskite structure, is found. Above ~ 700 K, the specific electrical conductivity of the samples under study increases significantly, which may be associated with an increase in ionic conductivity. The activation energy of electrical conductivity was ~ 1.2 eV, which is consistent with the value of the activation energy of ionic conductivity of zirconium dioxide
The dependences of the microstructure and physicomechanical properties of ceramics based on Si 3 N 4 ? TiN are considered in a wide range of mass ratios of components. The sintering process and the physical and chemical processes occurring at the same time, in particular, the dependence of the hardness and density of the material on the ratio of the conducting phase of titanium nitride and the dielectric phase of silicon nitride with values ??above and below the percolation threshold has been investigated. Obtained ceramics based on pure titanium nitride with high physical and mechanical characteristics (H = 21.5 GPa)
The optimal conditions for the synthesis of nanocrystalline powders Li 2 TiO 3 from a mechanically activated mixture of lithium carbonate and rutile by the solid-phase method have been found. The effect of the firing temperature on the characteristics and microstructure of ceramics from synthesized powders has been studied.
On the basis of local feldspar zeolite raw materials, the possibility of obtaining densely sintered ceramic products is shown. As a result of the optimal selection of the composition of the charge, materials of high strength and low water absorption were obtained.
Studies have shown that it is advisable to use high-alumina nanotechnological raw materials as a softener to increase the thermal stability of clinker bricks. With an increase in the compositions of the ceramic masses of aluminum oxide Al2O3, the thermal resistance increases, and the TLEC decreases during firing (1250 ° C) of clinker bricks. When the content of Al2O3 in ceramic masses is from 41 to 43%, the thermal resistance of clinker bricks reaches a maximum value and lies in the range from 11 to 13 cycles. As a result of regression analysis, a mathematical model was obtained that allows one to determine the thermal stability of clinker bricks at points that were not included in the series of experiments.
