METHOD FOR GROWING CARBON NANOTUBES IN CARBON FRAMES, METHOD FOR MANUFACTURING PRODUCTS FROM CARBON-CARBON COMPOSITE MATERIAL MODIFIED WITH CARBON NANOTUBES, AND CARBON-CARBON COMPOSITE MATERIAL Russian patent published in 2024 - IPC C01B32/158 C01B32/164 C04B35/83 B82B1/00 B82B3/00 B82Y40/00 

FIELD: chemical industry; metallurgy; space industry.

SUBSTANCE: method is described for growing carbon nanotubes in preforms, including carbon fibre frames, by the catalytic method in the gas phase, which includes impregnation with a precatalyst, drying the frame, followed by heating at atmospheric pressure in a carbon-containing gas to the temperature of its pyrolysis; wherein the frame is heated to a higher temperature, corresponding to the pyrolysis temperature of carbon-containing gas, from its inner surface, and the carbon-containing gas is supplied from the outer surface with a lower temperature, followed by the advancement of the zone with the pyrolysis temperature along the thickness of the frame. In this case, it is preferable to use network gas as a carbon-containing gas, with a methane content of 96 vol.%, and it is supplied after establishing a temperature of 750°C on the inner surface of the frame, which is the zero zone of pyrolysis of the network gas, with subsequent movement of the pyrolysis zone at a temperature of 750°C along the thickness of the frame at a speed of 0.5 mm/hour. A method for manufacturing products from a carbon-carbon composite material (CCCM) modified with carbon nanotubes (CNTs) includes formation of a frame based on carbon fibres, growing CNTs in its pores by the catalytic method in the gas phase and saturating it with pyrolytic carbon by the thermogradient method, carried out in a carbon-containing gas environment, wherein The growth of CNTs in the pores of the frame, preliminary and final saturation of it with pyrolytic carbon are carried out in a single technological process, while it is preferable that the preliminary saturation of the frame is carried out under the technological parameters of growing CNTs in the frame, and the final saturation with the movement of the pyrolysis zone with a temperature in the zone of 950°C at a speed of 0.25 mm/h using network gas with a metal content of 96 vol.% as a carbon-containing gas. Also described is a carbon-carbon composite material based on a frame of an orthogonal structure made of high-modulus carbon fibres and a pyrocarbon matrix, additionally containing carbon nanotubes located in the interfibre pores of the frame, with the following component content, in wt.%: carbon fibres - 21.2÷ 30.5; CNT - 1.4÷ 3.8; pyrocarbon matrix - 65.7÷ 77.4.

EFFECT: possibility of eliminating contact of service personnel with carbon nanotubes during the manufacture of products from carbon-silicon carbide and carbon-carbon composite materials, as well as creating prerequisites for reducing the cycle and cost of their production.

5 cl, 7 dwg, 3 tbl