Refractory Coatings of C-Me-Si and C-Me-B-Si Systems for Protection of Carbon Materials (CM)

Abstract
The three-zoned structure of the coatings for protection from high-temperature oxidation of carbon materials (CM) was grounded. The kinetic of formation and phase composition of diffusion coating C-Me-Si and C-Me-B-Si (Me = Ti, Zr or Hf) systems formed on CM (graphite and carbon/carbon materials) have been studied. The coating on CM received by using sequential metallization, boron- and silicium- deposition from dispersive solid-phased media. The rate of formation coatings of C-Me-Si by metallization and Si-deposition on CM decreases on the line : Ti--Zr--Hf, and the formation carbide layers MeC by diffusion metallization CM describes linear-parabolic law have been shown. The velocity of boron diffusion of the "CM - MeC layer" compositions is very little and it is increased on the line : Ti--Zr--Hf insignificantly. The formation of MeB₂ layer at the boriding are decreased of the velocity of siliciding. The coating proposed hase three-zoned structure formed by compounds of C-Me-Si or C-Me-B-Si systems and intended for protection of CM from high-temperature oxidation (T [MATH] 1400°C). The laws of phase form and destruction at high-temperature oxidation in air for these coatings are investigated.