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Determining the strength of high-temperature materials at a temperature exceeding 2000 K is an important problem. In particular, we note that very few studies have been carried out for determining the high-temperature strength of these materials in oxidizing media.We designed and installed a simple device (equipment) for determining the mechanical properties of the materials (in particular, oxide ceramics) including the tensile properties at 1700-2500 K in the environment of combustion gases.The device is fitted with an oxygen-gas burner* and consists of a ceramic channel (Fig~ I) that is sectionally constructed using sliced bricks of zirconia (zirconium dioxide) refractories having a granular structure. The test specimens % are freely accommodated in the channel and their fixing is carried out outside the channel. In view of the fact that the temperature at the ends of the specimen does not exceed 1000~ metallic clamps can be used for gripping. Heating is carried out using the oxygen-gas burner having a variable coefficient of excess oxidant (~ = 0.5-1.5); the maximum consumption of the combustion gases amounts to 2 g/sec.In view of the relatively low ultimate tensile strength of ceramics in the 2000-2500 K range (usually, it does not exceed 1-2 N/mm=), it is quite easy to obtain the required loads (for example, sand or metallic balls can be used). At 1700-2000 K, it is advisable to use more complex attachments (including a tensile testing machine).Using the developed device, we determined the temperature dependence of the ultimate tensile strength Otn s of the dumbbell-shaped specimens (Fig. 2) obtained from a water-cured zirconia concrete (hydration-hardened zirconium dioxide-based concrete) (WZC) containing 80% (weight contents) electromelted ZrO 2 of two fractions and 20% cement produced from a mixture