The features of the structure of porcelain items, which were molded by the pouring and pouring method of slip casting, have been determined. The possibility of identifying the method of manufacturing products has been established. The data obtained can be useful for determining the mechanism of defects in porcelain produced by casting. Tab. 2, ill. 7, bibliography. 3 titles
The influence of colemanite additives on sintering, properties and microstructure of spodumene ceramics has been investigated. It has been established that the introduction of colemanite in an amount of 5-7% is most effective for intensifying sintering processes and forming a denser ceramic structure. Received spodumene ceramics with TCLE (9.8 ... 12.9) & sdot; 10 -7 К -1 , heat resistance more than 100 thermal cycles (800 ° С - water), water absorption 0.7 - 5.0% and mechanical strength in bending 33 - 44 MPa, provided at a firing temperature of 1200 ° C. Il. 4, bibliography: 8 titles.
A method of obtaining yttrium-stabilized zirconium ceramics by cold isostatic pressing without using a binder from zirconium dioxide nanopowder obtained by the method of reverse coprecipitation is considered. The main characteristics of the powder have been determined by X-ray diffraction, BET, thermal analysis, transmission and atomic force microscopy. It was found that the Zr 0.92 Y 0.08 O 2 powder consists of a pure tetragonal phase with a particle size of 10 nm. The microstructure and composition of zirconium ceramics were studied by SEM and XRD methods. The data obtained on the transition of the tetragonal phase of zirconium ceramics to the monoclinic phase with an increase in the sintering temperature are associated with the growth of the ceramic grain at high temperatures. Il. 5, bibliography: 4 titles.
The data characterizing the properties of molding masses for extrusion of complex-profile thin-walled products are presented. To characterize the molding properties of the masses, it was proposed to use such parameters as the ratio of deformations, the relaxation period, the power for the destruction of the coagulation structure, and the flow index. For extrusion, masses with developed plastic properties and a strong coagulation structure are recommended. Tab. 1, ill. 5, bibliography: 24 titles.
The dimensional and morphological parameters of nanopowders of the ZrO 2 - СеО 2 system obtained from carbonate and hydroxide precursors have been investigated. The effect of the nature of the precipitant and the temperature of heat treatment on the morphology of the synthesized powders, their agglomeration and porous structure is shown. The revealed differences in the structuredness of powders affect the sintering process and the preparation of samples of various degrees of compaction. Tab. 3, ill. 5, bibliography: 10 titles.
It is shown that the use of alkaline etching slimes as a thinner in ceramic masses based on unenriched kaolin clay makes it possible to obtain high quality clinker products. Tab. 2, ill. 2, bibliography: 5 titles.
A gas-dynamic model of the formation of open and closed porosity of materials under the conditions of combustion of an SHS system, when there is a liquid phase (which can boil under certain conditions), the pressure of impurity gases, vapor of the liquid phase, external pressure or vacuum, is considered. It is shown that there is a critical pressure that characterizes the transition boundary between closed and open porosity. Experimental studies for the Ti - C system showed that the size of the open pores of the synthesized sample, measured over the sample volume, correlates with the calculated values ??that were obtained when considering the gas-dynamic model of the formation of open porosity using the theory of cavitation. Il. 3, bibliography: 9 titles.
The results of studies on the synthesis of brightly colored lilac and light green pigments in the CaO - SiO 2 system with the addition of chromophore oxides and modifiers are presented. The process of formation of the structure of the pigment and the optimal temperature of synthesis have been established by methods of X-ray phase analysis and IR spectroscopy. The results of testing pigments in glaze melts are indicated. Tab. 1, ill. 2, bibliography: 5 titles.
According to the developed technology of solid-phase sintering based on raw materials SiO 2 nH 2 O, ZrO 2 and MnO 2 , Co 3 O 4 , NiO As a source of chromophores, zircon ceramic pigments of gray, lilac and gray-lilac colors were obtained. The sizes of the crystals are, respectively, from 2 to 5 to 10 microns. The synthesized pigments were investigated by X-ray phase analysis using a spectral photometer and a scanning electron microscope. Tab. 2, ill. 4, bibliography: 3 titles.
The structure of the "casting spot" defect on porcelain items has been investigated. Recommendations for eliminating this defect are given. These recommendations can also be used in the manufacture of products by casting from earthenware, majolica and other materials. Tab. 1, ill. 3, bibliography: 1 title.
