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The article considers a possible approach to obtaining a high-temperature composite material with a matrix based on aluminum oxide reinforced with zirconium oxide. The article describes a method for manufacturing samples of ceramic composite material. A comparative study of the compositions and technological methods of manufacturing ceramic composite material is carried out. The prospects of the CСМ composition based on mullite modified with zirconium oxide are substantiated. The advantage of obtaining ССМ by semi-dry pressing is described. The choice of the further direction of development is justified
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The features of batch mixing for flint and heat absorbing bronze glass melting containing selenium are considered. Methods to decrease selenium losses during glass mixture transportation and glass melting are presented. The possibility of using diatomite and soluble sodium silicate for these purposes is investigated
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The dielectric characteristics of the kaolinite mass in the frequency range from 200 to 3500 kHz are investigated. The influence of the mass humidity on the values of the real and imaginary components of the permittivity is considered. The samples were obtained from clay of the Orenburg region mixed with distilled water, containing more than 70 % kaolinite with particle sizes represented by three modal maxima, microns: 0.14 +- 0.05, 1.13 +- 0.40 and 23.4 +- 2.70. It has been established that the dielectric permittivity of wet (26.5 %) samples is two times higher than that of dry (7.8 %) and three times higher than that of fired (= 0 %). It is shown that the dependence of the permittivity on humidity is approximated by a quadratic equation
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The influence of a number of modifying additives: calcium fluoride, zinc oxide and boron oxide, on the melting and crystallization properties of strontium aluminosilicate glasses is considered. The influence of the type and amount of the modifying additive on the homogeneity of the molten glass and the quality of glass castings was visually evaluated. The influence of additives on the formation of the crystal structure of glasses was studied by methods of mass crystallization and XRD.
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The advantages of alkoxy technology as one of the types of the sol-gel method for the synthesis of ceramics and glass ceramics are shown; an overview of the methods for the synthesis of alkoxides and oxides based on them is presented. The results of experimental studies on the production of mullite glass-ceramics using the alkox technology method are described, the structural and phase transformations of the intermediate product in the process of mullite synthesis are studied.
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A technology has been developed for producing glass microspheres in a plasma reactor based on the wastes of enrichment of ferruginous quartzites KMA. The regularities of the influence of the flow rate of the plasma-forming argon gas and the power of the plasma reactor on the fractional composition have been established. It is shown that with an increase in the flow rate of the plasma-forming gas from 1.5 to 2.5 m3 / h and the current strength from 400 to 500 A due to the processes of coagulation, the amount of the fraction over 630 ?m increases. It has been shown that glass microspheres are enriched in aluminum and calcium oxides and depleted in silicon, magnesium, sodium, potassium, and iron oxides. It was found that under the action of high plasma temperatures, of the order of 9000 & # 150; 12,000 K, there is a complete melting and spherization of the particles with the formation of glass microspheres with a size of 80 to 1250 microns. The following operational parameters of glass microspheres based on the wastes of enrichment of ferruginous quartzites of KMA, such as microhardness, acid resistance and alkali resistance, have been investigated.
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It is shown for the first time that the slurry evacuation method can be used within the technology of manufacturing large-size radio-technical items from quartz ceramics. According to the results of the study, it was found that evacuation of a slip based on quartz glass before molding ceramic blanks makes it possible to increase the level of density values ??of the ceramic material by 0.01 g / cm
3 and improve its uniformity by more than 30 & # 37; , as well as to reduce the number of cavities in products made of quartz ceramics by removing air from the slip
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The effect of the content of silicon carbide whiskers and the sintering temperature on the physicomechanical and thermophysical properties of samples of a ceramic composite material (CMC) of the SiC & # 150; SiC
w & # 150; B
4 system has been investigated. C & # 150; AlN with a mass content of silicon carbide whiskers (SiC
w ) 10, 30 and 50 & # 37; obtained by the method of spark plasma sintering. The introduction of silicon carbide whiskers SiC
w into the CMC of the SiC & # 150; B
4 C & # 150; AlN system led to an increase in bending strength and crack resistance, and at a mass content of SiC
w 30 and 50 & # 37; values ??of strength and crack resistance of PFC are at the same level
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The results of studies of the structure and properties of traditional ceramic stone masses, including in the initial composition emaciated, flux and clay materials (respectively 36, 14 and 50 & # 37; by weight) with a systematic change in the ratio of kaolinite and illite-containing clays and temperature-time conditions of firing in the temperature range 1000 & # 150; 1300 & # 176; C. As a result of studies of the structure, phase composition, dilatometric and ceramic properties, the optimal ratios of kaolinite and illite clays and the sintering conditions under which the ceramic properties of the material are realized are determined. It is shown that the maximum compaction of ceramics (open porosity / water absorption 2 & # 150; 5 & # 37;, apparent density & # 8805; 2 g / cm
3 ) is achieved in the range of sintered state 1150 & # 150 ; 1250 & # 176; C and is realized while maintaining the equivalent mass ratios of both clays in the original compositions close to 1: 1
