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Data on interactions in the ZrO 2 -Fe 2 O 3 system stabilized by oxides in a high-temperature form at 1750°C are obtained. Of all zirconia-based compositions, only magnesium-zirconium cubic solid solution enters into an active reaction with Fe 2 O 3 to yield MgFe 2 O 4 . The solid solutions formed by ZrO 2 with oxides of yttrium, neodymium, and calcium resist degradation by attack from Fe 2 O 3 ; part of iron oxide undergoes dissolution in cubic ZrO 2 .Components made of zirconium dioxide are promising for service in the metallurgical industry [1, 2]. Zirconiabased materials, owing to their high resistance to molten metal, have found application in the manufacture of the proportioning equipment for continuous casting machines in special steel technologies or the inserts for slide-gate plates. As is known, the main reason for the rapid wear of refractories exposed to molten steel is corrosion which, as a rule, results from the interaction of refractory constituents, slag, and oxide impurities in the metal.In what follows we report on the results of an experimental study of the high-temperature interaction between Fe 2 O 3 (a major component of metallurgical slags) and zirconium dioxide stabilized (fully or in part) in the high-temperature cubic modification by oxides.Stabilization of the high-temperature ZrO 2 was carried out in the following manner.Baddeleyite concentrate (available from the Kovdorskii Mining and Dressing Kombinat, Kovdor, Murmansk Region, Russia), first grade, £ 98.5% ZrO 2 , fraction 0.5 -0 mm, in a mixture with a stabilizing oxide, was ground in a rubber-lined vibratory mill for 15 h at a grinding balls : material ratio of 9 : 1. The stabilizing additives used were 12 mol.% CaO, 12 mol.% MgO, 12 mol.% Nd 2 O 3 , and 3.8% Y 2 O 3 . The finely dispersed mixtures (with a specific surface of about 3000 cm 2 /g) were pressed into briquettes under a pressure of 100 MPa using a bond (a 5% polyvinyl alcohol solution). The briquettes were fired in air at 1750°C for 4 h. The fired briquettes were crushed and finely ground to obtain a fraction of 0.25 -0 mm. The finely ground powders were subjected to magnetic separation and mixtures of stabilized ZrO 2 and Fe 2 O 3 were prepared at specified component ratios. The mixture components were homogenized in a rubber-lined vibromill for 15 h at a ratio of 9 : 1 (see above). The finely ground mixtures were pressed into cylindrical pellets of diameter and length 15 mm under a pressure of 100 MPa; the bond was a 5% polyvinyl alcohol solution added at a concentration of 6 -7%.

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Concrete examples of new technological and engineering designs of effective refractory materials for use in metallurgy and the glass industry are presented. It is shown that the OAL Borovich Refractory Combine has expanded the degree of diversification of its production activity not only through the development of new types of products, but also through the startup and operation of services that are new for the enterprise, such as engineering and bench pre-assembly of the bottom and other elements of glass making furnaces.For the OAO Borovich Refractory Combine, 2009 was one of the most difficult in its recent history. A critical situation that affected the basic consumers of refractory materials, in the metallurgical, cement, and glass making branches of industry lead to a reduction in the volumes of demand for refractories, and a decrease in the world price for petroleum led objectively to a decrease in the consumption of propants. The advantages of the two strategic directions for the development of the enterprise that had previously been decided on diversification and quality became fully apparent [1].Because of the high degree of quality of the output produced by the plant, the market and sphere of application of the traditionally fabricated output has expanded, there has been no drop in the volume of production, and highly skilled personnel have been retained. The principal advances achieved in the operation of the OAO Borovich Refractory Combine as regards increasing the quality of the output have been marked by the awarding of a number of certificates [2].The OAO Borovich Refractory Combine is a city-forming enterprise, hence to maintain a stable socioeconomic environment the management of the combine has never resorted to a sharp reduction in production, and besides expanding the product mix and the adoption of new types of products, the management has focused on increasing production efficiency, achieving economic gains, and avoiding bankruptcy. As the enterprise has developed, the accumulation of diversification capital at the OAO Borovich Refractory Combine has changed in form. The evolution of the diversification of the product manufactured at the OAO Borovich Refractory Combine, is presented in Table 1.The Borovich Combine produces refractories for all the different divisions of the ferrous metallurgy industry, including aluminosilicate articles for the brickwork of coke ovens and blast furnaces, Cowper hot-blast stoves, hot-metal transfer and casting ladles, mixer cars (including those for mixer cars used for articles to which silicon carbide has been added), regenerators of open-hearth furnaces, the bridges of electric-arc, steel melting furnaces, corundum-graphite articles for use in continuous casting of steel, and articles for rolling. Moreover, the products fabricated by the OAO Borovich Refractory Combine are purchased by enterprises in the ferrous metallurgy, machine-building, construction materials and chemical industries as well as by power plants and other industries. The production of pe...