A study is made of the effect of dispersant additives on the properties of a mix and a fired material containing hollow corundum microspheres. It is shown tht the addition of CASTAMENT FS10 together with CASTAMENT FW 10 makes it possible to obtain a green product having an ultimate compressive strength of at least 2 MPa. The fired material is slightly less porous than the material without dispersant additives. Heat-insulating ceramics based on hollow corundum microspheres and having an open porosity of at least 50.7% and an ultimate compressive strength of at least 35 MPa are obtained after firing at 1600°C. The material shrinks no more than 0.2% during the firing operation, which has made it possible to make large products of complex shape and ship them to customers.

Ceramic filter elements based on aluminosilicate fibers were produced by vacuum forming, using various drying methods. Microwave drying and freezing followed by drying have been used as methods to reduce binder migration. The microstructure of the obtained filter elements, tensile strength and aerodynamic resistance were analyzed. The obtained characteristics were compared with the characteristics of filter elements made using convective drying. Ill. 6. Ref. 33. Tab.

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The prospect of using crystalline fused magnesia (FL LC) in the manufacture technology of melting crucibles by the method of isostatic pressing is shown. It has been established that the production of a material based on MgO using concrete technology is limited to the hydration and loosening of the structure due to the formation and subsequent decomposition of brucite (native magnesia). The physical and mechanical characteristics of the obtained products are given. The effect of the CaO/SiO2 ratio on the corrosion and erosion resistance of products is considered. The raw material should have a molar ratio of these oxides of more than 1,7. Pressed crucibles were tested in the production of nickel, cobalt and tin based alloys in a vacuum induction furnace. The parameters of operation of products in the enterprise are shown. The effect of clogging by crucible materials during smelting of pure nickel has also been studied. The absence of contamination of the melt with crucible materials such as silicon dioxide, aluminosilicates and oxide films, etc., has been established.

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