It is shownthat fully sintered ceramic mixtures for floor tile can be obtained from Berlinclay with additionof pegmatitefrom the Chupinskoe and Vishnevogorskoe deposits. The phase composition and microstructure of the synthesized materials are described.In Russia, ceramic floor tile is produced in correspondence with the requirements of GOST 6787-90 State Standard. The water absorption of the tile should not exceed 4%. At the present time, the building industry demands floor tile without open porosity and with zero water absorption. Such tile possesses high technical characteristics and can be polished, which improves considerably the appearance of the structures.As a rule, ceramic tile for floors is produced from mixtures that contain 80% plastic components and 20% fluxes (here and below in mass fractions) [1,2]. In order to obtain fully sintered ceramic mixtures, we studied compositions with a much higher content of fluxes (50 -70%).The ceramics industry does not use mixtures with such a high flux content, because in addition to the positive sintering action, the fluxes can have a negative effect, i.e., increase the susceptibility of the products to deformation and increase the closed porosity.We tested the raw components used by the Ekaterinburg Ceramic Plant, namely, Berlin clay and Chupinskoe and Vishnevogorskoe pegmatite. The chemical composition of these materials is presented in Table 1.We began with a study of some properties of the initial components. The properties of Berlin clay were studied in [3]. The thermogram of the Berlin clay obtained by us is presented in Fig. 1.In deciphering the DTA data, we established that the predominant clay mineral is kaolinite (the endothermic effect at 578°C caused by removal of chemically bound water from the kaolinite and the exothermic effect at 940°C connected with rearrangement of the metakaolinite lattice).The Berlin clay also contains montmorillonite (endothermic effect of removal of adsorption water at 185°C). Our 119 data on the mineralogical composition of the Berlin clay coincide with the results of [3]. i.e., the Berlin clay has a kaolinite-montmorillonite composition. We used the method in [4] for calculating the activation energy of the process of removal ofadsorption water, which amounted to 28 kJ Imole, and the energy of removal of chemically bound water from kaolinite, which was 89 kl/mole, Berlin clay belongs to the medium-plastic category. The picnometric density of the clay in the natural state is 2.53 g/cm 3 • The clay is moderately sinterable at a moderate temperature.In order to determine the heating behavior of Vishnevogorskoe and Chupinskoe pegmatites, these materials were preliminarily crushed (no residue on screen T Fig.

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