Method of producing protective coatings on articles with carbon-containing base. RU patent 2458893.

FIELD: chemistry.

SUBSTANCE: invention relates to production of carbon articles and materials and is meant for protecting articles operating in oxidative medium conditions at high temperatures, for example in metallurgy industry, aircraft building and other industries, from oxidation. The method involves formation on the surface of the article of a slurry coating based on a composition consisting of a mixture of fine powder of carbon and a refractory metal or compound thereof and a binder, heating the article in silicon vapour in a vacuum in the volume of a reactor with subsequent ageing and cooling. The refractory metal or compound thereof used is Mo and/or W and/or "И", and/or Zr and/or Hf, which are active towards silicon, and/or compounds thereof such as carbides and lower silicides of these metals, e.g., Mo₂C, MoC, W₂C, WC, TiC, ZrC, HfC, Mo₅Si₃, W₅Si₃, Ti₅Si₃, Zr₅Si₃, Hf₅Si₃ or similar. The article is heated in silicon vapour at pressure 1-36 mm Hg to temperature 1500-1750°C and held in said temperature interval and pressure for 1-3 hours, after which the article is cooled in silicon vapour. Heating from 1000°C to 1500-1750°C is preferably carried out at a rate of not more than 150°/h with isothermic ageing at temperatures where chemical reactions for forming silicides are intense.

EFFECT: high heat resistance and wider range of obtained coatings.

2 cl, 3 tbl

IPC classes for russian patent Method of producing protective coatings on articles with carbon-containing base. RU patent 2458893. (RU 2458893):

C04B41/87 - Ceramics

C04B35/58 - based on borides, nitrides or silicides

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