METHOD OF MANUFACTURING OF TIGHT ITEMS OUT OF CARBON-SILICON CARBIDE COMPOSITE MATERIAL Russian patent published in 2015 - IPC C04B41/87 C04B35/532 C04B35/573 

FIELD: metallurgy.

SUBSTANCE: invention relates to carbon-silicon carbide composite material (CSCM) operating under conditions of high thermal loading and oxidating medium, and can be used during construction of the missile-space equipment, where the items are subjected to tight requirements under overpressure. Method of manufacturing of tight items out of CSCM includes billet manufacturing out of porous carbon containing material, which components have similar CLTE, and its silicification by vapour-liquid method by heating, holding and cooling in silicon vapours. During silicification the billet is taken with predominant size of pores maximum 40 mcm, prior to its silicification in the surface material pores slurry composition out of carbon powder or its mixture with compounds is rubbed in, they have CLTE close to CLTE of the material components of the billet, then on the item surface the slurry coating is formed based on the said composition. In composition for the slurry coating formation at the side of fired surface the powders with particles size equal or exceeding size of the predominant material pores by maximum 2-2.5 times are used. In the slurry coating for the opposite surface of the item the powders with size below 5 mcm, including nano sizes are used. The silicon macro transfer to the material pores of the billet and slurry coating is performed by means of the capillary condensation of its vapours at the heating stage and/or isothermal holding in temperature range 1300-1600°C at silicon vapours temperature exceeding the temperature of the siliconised billet.

EFFECT: production of tight items out of CSCM for use at temperatures exceeding melt temperature of silicon in vacuum, and under overpressure.

3 ex, 1 tbl