METHOD OF MAKING ARTICLES FROM CARBON-SILICON CARBIDE MATERIAL Russian patent published in 2013 - IPC C01B31/04 C04B35/52 C04B35/565 C04B41/81 

FIELD: chemistry.

SUBSTANCE: invention can be used in chemical, petrochemical and chemical-metallurgical industry, as well as in aircraft engineering to make structural materials operating in conditions of high thermal load and oxidative media. A slurry coating based on a composition of a siliconising agent and a temporary binder is formed on a workpiece made from porous graphitised carbon material. The inner layer of the slurry coating is formed from silicon nitride, and the outer layer is formed from silicon or silicon encapsulated in a silicon nitride cladding. The workpiece is siliconised by heating to 1800°C in a vacuum or at atmospheric pressure in argon, holding for 1-2 hours at 1800-1850°C and cooling. The first mode includes heating from 1000°C to melting point of silicon at a rate of 350-500 deg/h; to 1650°C at not less than 200-250 deg/h and to 1800°C at a rate of not less than 100-200 deg/h. The second mode includes heating from 1000°C to 1300-1400 °C at a rate of 200-250 deg/h, isothermic holding in said interval for 40-60 min, heating to 1700°C at a rate of not less than 300-350 deg/h and from 1700 to 1800°C at a rate of not less than 100-200 deg/h. In both modes, heating in the interval 1600-1650°C is carried out at reactor pressure of not more than 300 mm Hg, and heating in the interval 1650-1800°C, isothermic holding at 1800-1850°C and cooling are carried out at reactor pressure of not more than 36 mm Hg.

EFFECT: simple method of making large-size articles, high purity of the surface of said articles and strength.

4 cl, 2 tbl, 21 ex