METHOD OF MAKING AIRGTIGHT ARTICLES FROM CARBON-SILICON CARBIDE MATERIAL Russian patent published in 2013 - IPC C04B35/532 C04B35/577 

FIELD: chemistry.

SUBSTANCE: invention relates to carbon-silicon carbide composite materials operating in conditions of high thermal load and oxidative medium and can be used in chemical, oil and metallurgical industries, as well as aircraft engineering to make articles and structural components exposed to aggressive media and requiring air-tightness of the articles made from carbon-silicon carbide composite material. A workpiece is made from porous graphitised carbon material. The porous graphitised carbon material of the workpiece for siliconisation is material whose components have a coefficient of linear thermal expansion in the range of 3-6×10^-6 deg^-1. The workpiece is heated in the vessel of a closed volume in an inert atmosphere or in a vacuum in silicon vapour. Heating is carried out to 1500-700°C or 1700-1900°C at pressure of 1-36 mm Hg and 1-860 mm Hg, respectively, followed by holding in said temperature and pressure intervals for 2-3 and 1-2 hours, respectively. The workpiece is cooled in silicon vapour: to 1350°C at pressure 1-36 mm Hg at a rate of 100-200°C per hour.

EFFECT: preventing formation of cracks in the workpiece and enabling the manufacture of airtight articles from carbon-silicon carbide composite material.

6 cl, 32 ex, 1 tbl