Russian scientists have developed six compositions of high-entropy ceramics with low thermal conductivity, high temperature stability, and radiation resistance. The material is considered promising for thermal barrier coatings in aerospace technology, radio electronics, and other systems operating in extreme conditions. The development by UrFU was reported by the Russian Ministry of Education and Science.
Specialists obtained six compositions of high-entropy ceramics. The material is a single solid solution of five or more components with a common crystal lattice. By selecting the ratio of components, scientists can change the properties of the resulting ceramics, in particular, their behavior at high temperatures.
Of particular interest for aircraft engine manufacturing is a comparison with already used stabilized zirconium dioxide. According to the Ministry of Education and Science, the new ceramic has lower thermal conductivity, and its coefficient of thermal expansion is better matched with the characteristics of metals.
Some samples also showed almost no change in structure after irradiation, whereas stabilized zirconium dioxide showed structural changes at comparable doses.
However, the value of 2050–2100 °C cannot yet be considered a confirmed operating temperature for the material. According to preliminary results of visual thermal analysis, melting in the obtained compositions begins precisely in this range. Additional research is required to determine the possibility of long-term operation at such temperatures.
For the PD-14, ceramic thermal barrier coatings based on yttria-stabilized zirconia are already used. According to ODK, such a layer on turbine blades reduces the temperature of the metal base by approximately 100–150 °C.
For prospective aircraft engines, such materials also represent potential interest. Earlier, the development of ceramic thermal barrier coatings for power units capable of withstanding up to 1250 °C on the surface was reported. Simultaneously, new heat-resistant materials and coating technologies are being created for the prospective engine. However, the possibility of using the developed ceramics directly in the PD-14, PD-35, or other serial engines has not yet been confirmed. This will require additional material testing and evaluation of its suitability in specific designs.