Mrs, materials scientists created a ceramic material a carbonitride of hafnium, able to withstand a record temperature of 4200 °C. This confirms the results of computer modeling that predicted the refractory properties and high hardness such material. Previously, the most refractory substance with a melting point of 3990 °C was considered as tantalum carbide-hafnium. After the end of the pandemic coronavirus, the scientists plan to conduct an experiment that will determine the melting temperature of the new material.
The materials scientists of the National research technological University MISIS has created the most in the world refractory ceramic material a carbonitride of hafnium, can withstand a temperature of 4200 °C. this was reported in the journal Ceramics International.
To date, the tantalum carbide-hafnium with a melting point of 3990°C was considered the most refractory compound created by man. The idea of creating a more refractory substances, materials scientists the University has prompted the study of the American colleagues of 2015, which with the help of computer modeling predicted exceptional thermal properties and high hardness of the composite compounds of hafnium, carbon and nitrogen. According to the calculations of researchers from the United States, the substance must withstand approximately 4200°C, characterized by high conductivity and resistance to oxidation.
“For new material were used triple system hafnium-carbon-nitrogen. By self-propagating high-temperature synthesis we got the substance of the carbonitride of hafnium — rich nitrogen hafnium carbide,” — said in an interview with RT the author, Director of the research center of structural and ceramic nanomaterials MISIS Dmitry of Moscow.
Next, the researchers compared the fusibility of two materials: the source of hafnium carbide (melting at 3990 °C) and the obtained carbonitride of hafnium. With the help of the battery, and molybdenum electrodes are held in a high vacuum simultaneous heating of two materials. As a result, the melted carbide, and a carbonitride remained unchanged. However, at this point, the researchers note, the specific melting temperature of the new material above 4000 °C, they could not be determined.
To validate all properties of the new material predicted by computer simulations, scientists need to conduct additional experiments. For this purpose, according to Dmitry in Moscow, an agreement was signed with the joint Institute for high temperatures RAS on conducting pyrometric analysis, which was postponed because of the pandemic COVID-19.
After the lifting of restrictions planned study, during which a carbonitride of hafnium will be melted by the laser with simultaneous measurement of thermophysical properties, including the temperature of prawle��ia.
According to scientists, the development of such high temperature materials will be required for aviation, aerospace and military technology. At hypersonic speed and when passing through the Earth’s atmosphere, the engines, wings and nose cones of aircraft operate at temperatures above 2000 °C and must be protected from the external environment. Such devices applied ceramic thermal protection using the most durable and refractory composite materials.
Further to check the possibility of the use of carbonitride of hafnium in the aerospace industry planned hypersonic study ablation — evaporation of the outer layers of the material.
