METHOD OF PRODUCTION OF THIN-WALL PRODUCTS FROM COMPOSITE MATERIAL WITH VARIABLE CONTENT OF SILICON CARBIDE Russian patent published in 2016 - IPC C04B35/577 B82Y40/00 

FIELD: chemistry.

SUBSTANCE: method of production of thin-wall products from carbon-carbide-silicon compositional material with variable content of silicon carbide includes formation of framework of lamellar or lamellar-sewn structure from carbon and/or carbide-silicon fibres, its consolidation with carbon material with obtaining blank from carbon-containing composite material with open porosity, which reduces from protective layers to bearing layers of material of future product from 20-60 to 6-12%, and its siliconising. In the process of framework formation on the border between protective and bearing layers of future product layer of graphite foil and/or some border layers are soaked with suspension based on carbon nanoparticles; consolidation of framework with carbon material is carried out in the following succession: framework is partially consolidated with pyrocarbon vacuum isothermal method to its content 8-15 wt %, plastic blank is moulded on the basis of framework and coke-forming polymer binding agent, carbonised and saturated by pyrocarbon vacuum isothermal method at temperature 1000-1050°C to open porosity of material of bearing layers 6-12%. Protective layers of blank material from carbonised plastic from the side of their location are screened from access to them of carbon-containing gas, and temperature is set the higher, the smaller thickness of pyrocarbon-saturated blank is. Then, blank material pores are filled with nanodisperse carbon or mixture of nanodisperse and finely-disperse carbon with particle size not larger than 5 mcm, and siliconising is realised by steam-liquid phase method by capillary condensation of silicon vapours in temperature interval on blank 1300-1600°C, pressure in reactor being not higher than 27 mm Hg, at temperature of silicon vapours exceeding temperature of blank respectively by 100-10 degrees, with the following heating and exposure at temperature 1750-1800°C for 1-2 hours. Filling material pores with nanodisperse carbon is carried out by growing in them nanocarbon particles from gas phase, and capillary condensation of silicon vapours is carried out with heating from 1300 to 1600°C with isothermal exposure in said temperature interval.

EFFECT: extension of technological possibilities of method for production of thin-wall products from CM with variable in width content of silicon carbide and increase of their exploitation characteristics.

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