VOL 86, No. 8 (2013)

The features of thermally activated pore formation of the zeolite-alkaline charge are considered. It was found that when the dry granular charge is kept in air, free NaOH carbonatizes with the formation of hydrated sodium carbonate - Na ₃ [CO ₃] [HCO _{3] & middot; 2H 2 O. The same process occurs with NaOH occluded by intracrystalline pores and channels of zeolites. Sodium carbonate trapped in the intracrystalline pores and channels of zeolites is an additional source of pore-forming gas - CO 2. This makes it possible to obtain foam glass with a density of 100 - 150 kg / m ³ from zeolite-containing rocks.}

The change in some parameters of the nanoscale coating under the action of 0.1 N solutions of hydrochloric and nitric acid has been studied. It was found that the swelling in hydrochloric acid is more intense than in nitric acid. The intensity of dissolution of a nanosized coating in a 0.1 N solution of nitric acid is directly proportional, and in hydrochloric acid is inversely proportional to the duration of etching.

The composition of the heat-insulating porous material based on serpentinite has been developed. The natural components used in the charge, including serpentine and lake diatomite, make it possible to obtain a material with a forsterite content of more than 70%, the synthesis of which begins at 600 ° C, and to provide, in comparison with the known composition, high strength. High values ??of mechanical strength and low thermal conductivity allow the use of heat-insulating material for heating units and freezers.

The mechanism of forming the strength of a casting ceramic mold is shown. The schemes of the arrangement of the binder composition between the solid components are considered. Various options for the destruction of ceramics are shown. Great difficulties are noted for the creation of analytical methods for calculating the strength of ceramics. It is possible to increase the strength of a ceramic mold by treating it with aqueous solutions of salts. This information will help you choose the best method for hardening a ceramic casting mold.

The reasons for the formation and methods of preventing structural cracks during the molding of high-alumina ceramics on screw presses are considered.

The developed molding gypsum of improved quality is used in the casting of ceramic products using traditional and multiple casting technologies (Spagless). Such gypsums provide an increase in casting performance, an increase in the life cycle of gypsum molds and burrs.

The properties of basalt fiber obtained using low-temperature plasma have been investigated. Basalt wool has good physical and mechanical properties. Its chemical stability depends on the composition of the feedstock. Mineral wool obtained from the basalt of the Vasilievskoye deposit can be used to insulate surfaces with temperatures up to 500 ° C, from the basalt of the Suduntui deposit - up to 700 ° C.

The rheological properties and aggregate stability of molding solutions for the production of aluminosilicate fibrous materials are considered. The effect of acetate groups in polyvinyl alcohol on the properties of molding solutions is shown.

The microhardness of quartz ceramic was measured at three stages of heat treatment of the primary billet obtained by slip casting: after drying at 100 ° C; after sintering at 1190 ° C; after flaming surface treatment. Although the hardness of the final product is close to the known values ??for silica glass, the IR spectroscopy data indicate the presence of significant internal stresses in the material. The found high content of terminal atomic groups in the primary material is a favorable factor for the doping of Kersyl.

The paper presents the properties of reaction-bound calcium phosphate materials obtained by pressing a paste based on ?-tricalcium phosphate followed by holding in various solutions. The phase composition, solubility, mechanical characteristics of the obtained materials were investigated, and biological tests were carried out in vitro.