Steklo i Keramika (Glass and Ceramics). Monthly scientific, technical and industrial journal

 

ISSN 0131-9582 (Online)

It was found that it is possible to obtain high-strength ceramic paving stones based on loess rocks with the addition of 20 % glass waste powder. At the same time, the amount of moisture in the ation should be close to 10 %, which corresponds to the semi-dry pressing technoloformgy.

The publication presents general information about calcium zirconate and the physical/chemical characteristics of products based thereon. The main fields of application of ceramic and refractory materials based on CaZrO3 are also considered.

In the present study, we presented a review progress in sol-gel method for the synthesis of powders of ferroelectric ceramics of the PbTiO3–PbZrO3 system, based on the controlled hydrolysis of mixtures of salts or organometallic compounds of lead, zirconium, and titanium. To obtaining materials of the PbTiO3–PbZrO3 system, the main attention is paid to the sol-gel conditions, the heat treatment conditions, the raw materials, the obtaining the precursor conditions, the gels drying, and the PbTiO3–PbZrO3 powder crystallization.

Using glass as a structural element that could obtain the role of the primary load-bearing elements of iconoclast structures has had a superficial history. Because of its aesthetic and admissible mechanical properties, glass has been considered one of the structural elements in the construction industry. Because of its extra safety, laminated glass on top of the most widely used elements has been appraised with more depth. The study aimed to evaluate the failure modes in laminated glass and the possibility of detecting the pre-failure status of the surveyed elements, referring to the proffered approaches and image processing (IP) procedures in the literature. The outcomes have compared the peculiarity and strength points of various routes and have reached the inference for proper approaches in every procedure. According to the results, image processing (IP) is the most appropriate method of pre-failure detection in load-bearing laminated glass elements. Among the image processing (IP) techniques, digital image correlation has the widest application. The results of this study, in combination with other pieces of research, may propound a database for evaluating the failure status of glass structures.

The chemical resistance of glasses in the PbCl2–PbO–B2O3–NdF3 system has been studied. Oxochloride lead-borate glasses have demonstrated good water resistance and alkali resistance, while low acid resistance. Volumetric glass samples were exhibited in the tropical climate of Southeast Asia during the year. The spectral-luminescent characteristics of neodymium ions in these matrices maintain good stability in a tropical climate.

The possibility of using waste from the enrichment of ferruginous quartzites of KMA is considered. The chemical composition of waste from Lebedinsky GOK has been investigated. It has been established that the main components of the waste are quartz, magnetite, as well as dolomite, calcium and magnesium carbonates. It is shown that the chemical and granulometric composition of waste is characterized by stability, which allows them to be used as a corrective additive to ceramic masses in the production of wall ceramics.

The purpose of this work is to obtain ceramic filter materials as substrates and to develop a methodology for their application for the study of biological objects by electron microscopy. The composition, structure, pore sizes and morphology of ceramic substrates made of foamed silicate before and after the application of inverse opals made of silicon oxide were evaluated by X-ray phase analysis and SEM methods. A description of the use of the obtained filtering substrates in an experiment with biological objects is given. The substrates seem promising for electron microscopy, because they can be used for sample preparation of biological samples with the use of metal spraying or the introduction of ionic liquid. This technique, together with the filtering porous material and the technical capabilities of the microscope, preserves the physical characteristics of biological objects unchanged.

The article investigates the high-temperature interaction and sintering processes of samples of high-alumina masses of low-temperature firing for technical ceramics based on the ternary system kaolin–alumina-containing component–dolomite and establishes the areas of formation of high-alumina mass for technical ceramics on the triple diagram. It is shown that as a result of high-temperature interaction, new formation of crystalline phases of minerals occurs in the form of mullite, corundum, ?-cristobalite, as well as in a small amount of anorthite and an amorphous glassy phase, which impart the necessary physical and mechanical properties to the fired sample. The area of optimal compositions for obtaining high-alumina ceramic masses of low-temperature sintering based on the ternary system kaolin–alumina-containing waste–dolomite has been determined.

The chemical composition and technological properties of clay polymineral raw materials of the northwest of the Orenburg region have been studied. According to the chemical composition, the raw material can be attributed to semi-acidic sanded clays with a high content of coloring iron oxide Fe2O3 (4.83 %). The dependences of the viscosity of clay suspensions at sufficiently high concentrations (up to 0.16 vol. %); the linear character is confirmed by a high correlation coefficient and proves the absence of hydrate shells around particles containing a large amount of quartz in their composition. The values of the coefficient ? included in the Einstein equation are calculated, it turned out to be in the range 2.44 ? ? ? 3.0. The low plasticity of the raw materials, the studies of which were carried out in two ways – by squeezing the balls and bending the flagella, indicates a high content of sand. Sintering in the temperature range from 600 to 1000 °C did not happen, the samples cracked. Macroparameters of sintering and color parameters of samples under the influence of high temperature, as well as the results of the analysis of the phase composition do not allow us to assume satisfactory mechanical characteristics of ceramics from the studied raw materials. Low sorption properties of mineral raw materials with respect to copper and lead ions have been established. It is shown that the use of this raw material in the ceramic industry is not advisable, its use in road construction, landscaping, as thinning additives to reduce the plasticity and shrinkage of clays during drying and firing is more practical.

In this work, a study was made of the possibility of obtaining ceramics for microwave technology in the system of ZrO2–SnO2–TiO2 oxides by solid-phase synthesis using a sintering additive, lanthanum (III) oxide. Ceramics based on zirconium-tin titanate composition Zr0.8Sn0.2TiO4 with additions of 2, 4, 6 wt. % La2O3, its properties were studied using various methods of analysis. The densest ceramic specimens were obtained at a firing temperature of 1400 ?C and a La2O3 content of 4 wt. %.