The possibility of using local raw materials of Uzbekistan for the production of electrical ceramics is shown. It has been established that samples in which the silica component is largely represented by cristobalite have optimal mechanical and electrical characteristics. Tab. 5, ill. 1, bibliography: 2 titles.
The results of the study of the structure of porous multilayer ceramic filter elements are presented and the possibility of their use for clarification and sterilizing filtration of an antidiarrheal energy preparation is evaluated. Tab. 1, ill. 5, bibliography: 3 titles.
The parameters of more than 40 different types of grinding bodies produced or developed by domestic and foreign manufacturers have been analyzed. It has been established that the wear resistance of ceramics is determined by two groups of factors: external (characteristics of the technological process, design features of grinding units, shape and size of grinding bodies) and internal (characteristics of the structure, composition and properties of materials). The ceramic structure has a primary effect on the wear resistance of similar materials. The wear resistance is increased both by increasing the content of corundum in the mass and by adjusting the microstructure of the ceramic by introducing modifying additives. The most promising additives are eutectic compositions. Tab. 1, ill. 1, bibliography: 11 titles.
Data on the thermophysical properties of NZP ceramics with the structure of the NaZr 2 (PO 4 ) 3 type are generalized. A system of regularities of thermal expansion is proposed, which makes it possible to purposefully predict NZP materials with controlled, including ultra-low, thermal expansion at close to zero anisotropy. The thermodynamic functions of reactions for the synthesis of NZP-phosphates are calculated and the applicability of ceramic technology for their production is substantiated. It is proposed to use NZP-ceramics as heat-insulating materials capable of operating under conditions of sharp temperature changes. Tab. 4, ill. 4, bibliography: 25 titles.
The microstructure of material samples based on natural wollastonite was investigated at various sintering temperatures (850 - 1100 ° C). The influence of microstructure on porosity, shrinkage, water absorption and mechanical strength is shown. The essence of physical and chemical processes is explained. Physical and mechanical characteristics of the material are given. Tab. 1, ill. 2, bibliography: 7 titles.
A comparative analysis of the machining of ceramic materials based on aluminum oxide, silicon nitride and carbide has been carried out. Recommendations are formulated for choosing the type of grinding wheel, grinding speed and pressure exerted by the wheel on the workpiece. Tab. 2, ill. 3.
The issues of using flue emissions from thermal power plants - hollow ceramic microspheres - in syntactic materials with increased dielectric characteristics are considered. Comparative dielectric properties of the obtained materials and materials based on hollow glass microspheres are presented. Tab. 1, ill. 1, bibliography: 3 titles.
The thermal expansion of mullite-cordierite, mullite and quartz ceramics, which was used to obtain materials with protective coatings from Nb 2 O 5 , has been investigated. It is shown that, in terms of the nature of thermal expansion, the closest to Nb 2 O 5 are fused quartz glass and quartz ceramics in the absence of cristobalite phase in it. Variable composition alloys (Nb 2 O 5 ) x - (SiO 2 ) 1- x < / sub> have intermediate TCLE and can be used to compensate for the stress mismatch between the coating and the quartz ceramic substrate. Il. 5, bibliography: 6 titles.
The use of porous ceramics from disthene-sillimanite concentrate as a filtering material in aggressive media is proposed, the influence of the plastic component (bentonite) on the properties of the resulting ceramics is considered, and the results of studying the processes of phase formation at a temperature of 1250 ° C with different isothermal exposure are presented. It was found that at this temperature mullitization of disthene and "improvement" of the structure of sillimanite take place. Tab. 3, bibliography: 6 titles.
By dehydration of a hydrated mixture of alumina cement and magnesia binder, a heat-resistant material based on aluminum-magnesium spinel with uniform crystallization was obtained. It was found that the use of the proposed method makes it possible not only to regulate the composition of the heat-resistant material, but also to significantly reduce the temperature of mineral synthesis. Tab. 3, ill. 2, bibliography: 2 titles.
