Researchers have developed technology that improves the flexural strength and fracture toughness of silicon carbide by 50%.
Silicon carbide is a promising structural material for the manufacture of refractory parts. Nowadays, it is increasingly used in industry as a semiconductor, construction, refractory and abrasive material. For example, it is used to make turbine blades, internal combustion engine parts and ceramics for the automotive industry..
Russian scientists have found a way to increase the strength of material for aircraft construction.
The problem is that due to the high sensitivity of silicon carbide to structural defects, it often has low tensile, flexural and fracture toughness. However, scientists from the National Research Technological University MISiS have found a way to improve the sinterability of the material by forming reinforcing nanofibers in it..
The team used the technology of self-propagating high-temperature synthesis, carried out in several stages. First, powders of silicon, carbon, tantalum and polytetrafluoroethylene were mixed in a planetary mill. Then, the resulting mixture was burned in a reactor, where nanowires were formed in it during combustion. At the last stage, the substance was sintered in a vacuum furnace.
This made it possible to synthesize silicon carbide with a reinforced matrix, which increases its flexural strength and crack resistance by 1.5 times. In addition to improving the mechanical characteristics of the material, nanofibers reduce the required temperature and sintering time from several hours at 1800-2000 °C up to 60 minutes at 1450 °C, reducing production costs and expanding the field of application in aircraft construction.
In addition to improving existing ones, researchers are also inventing new materials with amazing properties. Recently we announced the development of the world’s first material that cannot be cut or drilled.
text: Ilya Bauer, photo: NUST «MISIS», Nbc