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The physicomechanical properties and structure of mullitecorundum unformed refractories were investigated and tests of a pilot batch of refractory products for various purposes were carried out. The effect of the addition of nanoscale SiO2 (1 wt. %) on strength, structural (density, porosity) and operational characteristics of unformed refractories. The results show that this additive contributes to the formation of a structure with high apparent density and compressive strength (2,93 and 2,98 g/cm3, 87,3 and 162,1 MPa, respectively, for two types of refractories), reduces open porosity from 20 to 14 %, and also increases the resistance of refractory products (by the duration of their operation) by 25‒35 % compared to the resistance of the base refractory. The use of SiO2 nanoparticle additives reduces the consumption of refractory products and raw materials for their production, and also increases the profitability of production. Ill. 2. Ref. 19. Tab. 4.

The samples of concrete based on ferroalloy slag with cement and fly ash were produced by the method mechanochemical activation. The chemical, phase and granulometric composition, specific surface area, morphology and strength characteristics of the samples were investigated. Ill. 8. Ref. 10. Tab. 5.

Samples of cement stone on the basis of two types of blast furnace granulated slag with the addition of fly ash by mechanochemical activation were made. Their chemical, phase and granulometric compositions, specific surface area, morphology, strength characteristics are investigated. An analysis of the influence of the method of introducing alkali on the performance of compressive strength was made.

The possibility to produce the vibro- and self-flow lowcement periclase concretes was investigated in the article. It was shown that when the concrete mixture is prepared in conventional conditions the aggregate and the fne ground component based on the fused periclase hydrate very little if any: over three days of the concrete curing the brucite content doesn't exceed 1 %. The data received can be used as the basis for the further development of the magnesia concretes with advanced properties.Ill.1. Ref. 17. Tab. 2.

The modeling technique was proposed for the phase formation in the CaO‒MgO‒Al2O3‒SiO2‒FeO‒Fe2O3multicomponent oxide system. The technique can be used to predict the equilibrium phase composition for both the refractory and refractory-slag systems, as well as to modify the metallurgical slag's chemical composition, to extent the metallurgical unit's refractory service life, and in order to attaint the refractory-slag systems the mineral binding properties.Ill. 2. Ref. 7. Tab. 8.

The investigating results are given in the article for the deoxidizing effect on the non-metallic inclusion compositions tubes steels melted in the vacuum induction furnaces with periclase lining. The oxygen thermodynamic activity was calculated for the lanthanum, cerium, alumina and yttrium melts during four heats. The magnesia spinel inclusion's formation condition was evaluated depending on the deoxidizer's used and on the deoxidizing depth. It was shown how the reduced alumina concentration during the steel ladle treatment governs the non-metal inclusions' compositions and on the possibility of their modification during the commercial tubes steels melting.