Specimens of composite (BeO + TiO 2 ) ceramics with TiO 2 added in an amount of 5, 10, 20, 30, and 40 mass% are obtained. The temperature dependence of the conductivity of the (BeO + 30 mass % TiO 2 ) ceramics is studied. Conduction is ensured by the titania additive present in the ceramics in a strongly reduced state. The maximum temperature (950 K) at which the (BeO + 30 mass % TiO 2 ) ceramics preserves its conductive properties in air for a long time and, possibly, the capacity to efficiently absorb microwave radiation is determined. Heating in air at a temperature exceeding 960 K is accompanied by the processes of oxidation of reduced TiO 2 , which causes disordering of the structure and lowering of the conductivity. An electron microscope study is used to show that the distribution of TiO 2 in the BeO of the [BeO + (5, 10, and 30 mass %) TiO 2 ] system is nonuniform; inclusions of large regions of grouped TiO 2 microcrystals are encountered. This affects the physicochemical properties of the ceramics, the thermal and electrical conductivities in particular. In order to ensure a uniform distribution of TiO 2 in the volume of the ceramics it is recommended to introduce the dioxide into the composition of the BeO powder from solutions (hydrochemical method).

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