and L. N. SemykinaThe possibilities for improving the technical properties and performance of ceramics using traditional methods are almost exhausted. The strength factors obtained by conventional firing of ceramics are below theoretical levels and ceramic structures are incapable of adapting to various conditions of service, such as thermal shock, chemical corrosion, etc. This results in premature failure of ceramic articles and constructions.In principle the latest ceramic technology should provide the formation of a quasistable structure capable of changing readily with varying schedules, and of maintaining volume constancy during operations [ i ].Such ceramics should possess adequate initial strength capable of ensuring the integrity of the design elements in furnaces.A model of the structure reflecting our ideas about the combination of volume constancy with a transformation capacity may consist of a densely packed spatial lattice of a crystal at the points of which, instead of atoms, particles of solid phase are situated. The bond between these particles should be effected by the formation on their surfaces of an amorphous layer of inorganic compounds, capable of entering into polycondensation reactions, with the formation of strong , spatial polymers. The volume constancy of such a structure should be provided by using solid particles, for example, grains of fused oxides of the highest refractories.The necessary condition for realizing this model is the formation on the solid particles' surfaces of an amorphized layer, consisting mainly of the chemical elements of the solid phase, and implanted ions. These ions form compounds with a great capacity for polymerization [2].

One of the most important characteristics of ceramics is their ability to function in the presence of anisotropic fluctuations of temperature fields with retention of mechanical strength and structural integrity. Granular materials such as ceramic concretes ('keramobetons') that are based on ceramic binder suspensions form no exception to this [i]. However, the concretes obtained at the present time using aqueous ceramic binder suspensions of monomineral systems (mainly, siliceous systems) undergo significant volumetric changes (2.10-10.2%) and exhibit poor thermal shock resistance (not more than 3 thermal cycles) [2]. On the other hand, the concretes based on the scrap of the quartz ceramics and the highly concentrated binder suspensions (HCBS) of fused quartz possess the maximum thermal shock resistance but such ceramic concretes are prone to cristobalitization in the 1300-1600=C range. Chamotte concretes obtained using quartz--chamotte (two-phase) binders have a high thermal shock resistance (16 thermal cycles involving water quenching from 1300~[3] and high-alumina ceramic concretes based on the monomineral binder suspensions [4] withstand 24 thermal cycles (1300~ --water).In this context, it is of particular interest to prepare and study the properties of the multiphase refractory HCBS and the ceramic concretes based on them that possess superior thermal shock resistance due to the difference in the coefficients of linear thermal expansion of the components that, in turn, leads to the evolution of a structure containing microcracks. The raw materials used for obtaining a three-phase ceramic suspension included quartz sand obtained from the u deposit (SiO 2 content 98 wt. %); scrap of the MKS-83 grade high-alumina refractories produced by the Semiluksk Refractories Plant (its chemical composition is as follows, %*: 13.34 Si02, 83.06 A1203, 0.83 TiO 2, 0.74 Fe203, 0.13 CaO, 0.25 MgO, 0.20 K20, 0.29 Na20, and 0.52 FeO); and unstabilized TsRO-I grade zirconium dioxide whose ZrO 2 content exceeds 99.5%. Based on these suspensions, we produced ceramic concretes in which the 3.0-0.5 mm fractions of sintered corundum (TU 14-8-89--73) were used as fillers.The suspensions were prepared by subjecting the raw materials to wet milling in a periodic-action ball mill according to the principles described elsewhere [5]. In order to control the properties of the suspensions and the castings based on them, we used the method of tribochemical implantation of reagents at the surface of the particles of the dispersed phase of the suspensions [6]. An aqueous solution of liquid glass formed the carrier of the implanted ions (Na § OH-, and [Si0414-). Table I shows the composition of the dispersed phase at different proportions of the components and the properties of the castings based on the obtained suspensions. The unstabilized ZrO 2 was introduced into the suspensions in the form of the minus 3-~m fraction (the Nos. 2-5 systems) after milling (for stabilizing and adjusting the content of the dispersing medium) and the minus 0.5-...

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