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An opportunity of using solar energy to develop a multicomponent ceramic material synthesis technology using melts has been demonstrated. Optical and energy parameters of the 1 MW Large solar furnace for synthesizing aluminum titanate-based materials are presented along with their phase and grain size compositions depending on the melt cooling rate. A possibility of obtaining a two-phase material containing the tialite phase and spinel is shown. A positive effect of the spinel phase on the properties of ceramics made from the material synthesized by using solar energy has been established.

In this study, the potential possibilities of the precision of the vibrating reed method for the evaluation of the . of superconducting precursors in an HTSC Bi-Pb-Sr-Cu-O system were investigated. A special technology for obtaining these samples by using solar energy for melting and following superfast melt quenching was applied to increase their internal inhomogeneity, allowing to receive high-quality textural ceramic samples of Bi1,7Pb0,3Sr2Can-1CunOy (n=2-30) showing critical temperatures of superconducting precursor transitions above bulk Tc. To determine critical temperatures of superconducting precursors above bulk Tc for the first time, the original vibrating reed method of studying these multiphase samples in an applied magnetic field was used. It was shown that this method has sensitivity to superconducting diamagnetism making possible to reveal new superconducting precursor phases above bulk Tc.

The phase composition of composite ceramic based on aluminum titanate and additives synthesized by concentrated solar radiation by means of solid phase reactions and by the induction method is investigated. It is revealed that the additives positively influence the sample’s mechanical properties.

The mechanical properties of an aluminum titanate-based ceramic are increased by decreasing the grain growth kinetic of the initial material, which is synthesized by melting in a solar furnace. The thermomechanical properties are improved if the following additives are introduced: mullite, spinel, and a eutectic of Al2O3-ZrO2.

cited By 1; International audience; Production of superconducting ceramics based on precursors with rated composition Bi1.7Pb0.3Sr2Ca2Cu 3O y is studied. The precursors are synthesized in a solar furnace by melt rapid quenching. The phase composition of the samples is examined by microstructural and X-ray analyses. The temperature dependences of the resistance and magnetic susceptibility are measured. The influence of the composition and crystal structure of the substrate on texturing in the Bi-Sr-Ca-Cu-O system is studied. It is found that the type of quenching plays a significant role, while the type of substrate is of minor significance. © 2009 Pleiades Publishing, Ltd.

The properties in isostructural and isostoichiometric series of monotitanates and dititanates of the rare earth elements (REE), titanates with structure of pseudobrookite type, and solid solutions with fluorite structure based on ZrO2 and HfO2 are investigated. The differences determined by molten phase synthesis via the action of concentrated solar radiation are shown. It is proposed that ozone and excited valence electrons, i.e., the factors caused by concentrated solar radiation, influence the phase composition and properties of these oxide compounds.

The moldability and sinterability of the experimental chamotte specimens with the addition of Angrensk clay are examined. Data are presented on the deformation phenomena after sintering at 1150 to 1450°C. The thermal resistance and the strength of the specimens are studied, and also the effectiveness of the use of protective coatings with the addition of corundum that is obtained in the Big Solar Furnace. Conclusions are drawn on the possible use of these materials in the mixers of the glass smelting furnaces.

The possibility of synthesis of alumino magnesium silicate (MgO-Al2O3-SiO2) on a Big Solar Furnace is demonstrated. Thermomechanical properties of ceramics based on it are investigated. The obtained material has high mechanical and dielectric properties, and spark-resistant electrical insulating products can be produced from it.

The properties of the spherulites based on aluminum oxide, mullite, and zirconium dioxide that are obtained by melting and subsequent quenching in a 1000 kW solar furnace are studied. These spherulites are hollow. The thickness of the wall of the sphere is determined by the quenching rate. The microstructure of the spherulites that are based on aluminum oxide consists of crystallites of cubic form, the microstructure of the spherulites that are based on zirconium dioxide consists of micrograins of rounded form. The hardness and the elastic properties exceed the known values for the electrically melted materials that are based on corundum and zirconium dioxide.

The possibility of obtaining basalt fiber based on mineral raw material from Uzbekistan using heating by concentrated solar radiation is investigated. The phase composition and properties of the basalt fiber obtained by a conventional technology using gas and solar energy as an energy carrier are studied. The parameters of the solar furnace in the technological process of obtaining basalt fiber are determined. The first results attest that concentrated solar energy can be used to produce ‘green’ technologies for obtaining fibrous materials.