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The Pervouralsk Dinas Works has developed mullite-silica vibrocast concrete of grade MKRV. In developing this grade we took into account all positive and negative aspects of the service of the previously used mullite-corundum concrete grade MKV. As a consequence, the mechanical strength of the concrete was raised in the whole service temperature range, its open porosity decreased and, accordingly, its impregnation with slag and metal decreases, and its heat-insulating properties were improved.

Compositions have been developed for nonshrinking vibrocast thermally insulating light refractory concretes with densities of 1.0, 1.3, 1.5, and 1.8 g/cm 3 for temperatures of use up to 1400°C. The structure and properties have been examined for the concrete of density 1.3 g/cm 3 .Advances in metallurgy and other branches of industry impose new requirements on the properties of light-weight refractories, and one needs better refractories with a combination of properties providing the reduction of energy, materials, labor, and time during production.Although there has been a general reduction in the production and use of refractory materials, there has been an increase in the proportion of production for unmolded refractories having many advantages over the usual ones. Out of all forms of unmolded refractories, the commonest have been refractory concretes, both traditional ones with high contents of cement and low-cement new-generation ones.When heat-insulating refractories are used in industrial ovens, there is 20 -70% reduction in the consumption of fuel, and it is possible to accelerate substantially the firing in batch ovens while also reducing the wall thicknesses in ovens and domes. If the thermal insulation is provided by high porosity, then the mass of the lining is also reduced.It is important to develop light concretes with low density and thermal conductivity, which can be transported in the form of dry mixtures and from which one can produce the lining by vibrocasting directly at the user=s plant.This study was performed to develop compositions for light refractory concretes with various densities on the basis of available and cheap raw materials. The basic concept was to use a light spherical aluminosilicate filler with closed porosity, which would allow one to use the minimum amount of water to obtain the vibrational flow state. Eliminating water from the structure of the concrete leads to the structure becoming more open and weaker, so the task is to minimize the amount of treatment water, including by the use of deflocculants and the addition of ultrafine powders.Rod specimens were shaped by vibration in demountable metal molds. The molds containing the specimens were kept for 24 h in a moist medium at room temperature. Then the

Results of scientific researches show the trend of active using nitrides and borides of transition metals and their combination in developing protective materials. While single elements nitrides have been well studied, their multilayer modifications and combinations require more detailed study. Physical-mechanical properties and structural-phase state of multilayer coating according to the deposition conditions is an important task for the study. It will be the analysis of physical-mechanical and electrical properties of coatings based on refractory metals nitrides, their structure and phase composition and surface morphology depending on the parameters of condensation. It was established the structure and behavior of nano scale coatings based on refractory metals nitrides (Ti, Zr) depending on the size of nano grains, texture, stress occurring in coatings.

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