The paper demonstrates methods for testing and selecting composite ceramics-compounds by solving inverse problems of mechanics. A method for the identification of physical and mechanical characteristics of the compound is proposed. The idea of the method is that the studied material is connected with other materials, the characteristics of which are well known and differ from the characteristics of the material. Desired physical and mechanical properties should be considered unknown in the proposed calculation model. Values of the parameters can be measured accurately with experimental methods in the process of product operation. Characteristics of test materials and geometric dimensions of proposed structures are suggested. The solution of the problem of optimizing the tolerances of physical and mechanical characteristics of materials is proposed. In order to ensure the strength of the structure, the geometric dimensions of the composite construction ceramic resistor-compound are suggested