Hf (Ta) C ultra-high-temperature composite coating and preparation method thereof

Abstract

The invention discloses a Hf (Ta) C ultra-high-temperature composite coating, which consists of HFC with HfTaC2, wherein the molar fraction of HfTaC2 is 6-50 percent, and the HfTaC2 is distributed in the coating uniformly or in a gradient way. The preparation method comprises the steps of: placing a surface-treated substrate material into a low-voltage chemical vapor deposition furnace, and usingmixed powder of hafnium tetrachloride and tantalum pentachloride as a hafnium source and a tantalum source, methane as a carbon source, argon as a diluent gas and hydrogen as a reducing gas; and delivering the mixed powder into a reactor of the deposition furnace, and preparing the Hf (Ta) C ultra-high-temperature composite coating by surface deposition on the substrate material. Limitations of asingle coating in ablation can be overcome, advantages of all phases of the coating can be fully utilized, and requirements for long-time high-temperature protection of the substrate material can be satisfied. The process is simple and convenient to operate, the prepared coating is well combined with the substrate, no interlayer cracks or penetrating cracks can be produced, and the thermal shock resistance and ablation resistance are excellent. The Hf (Ta) C ultra-high-temperature composite coating is suitable for surface coating and high-temperature protection of carbon / carbon composite materials, carbon / ceramic composite materials, graphite, carbide ceramics and other materials.

Description

technical field

[0001] The invention relates to a Hf(Ta)C ultra-high temperature multi-phase coating and a preparation method thereof, which belongs to the technical field of chemical vapor deposition and is suitable for carbon / carbon composite materials, carbon / ceramic composite materials, graphite, carbide ceramics and other materials Surface coating and high temperature protection. technical background

[0002] Carbon / carbon composites have excellent high-temperature mechanical properties, low thermal expansion coefficient, high thermal conductivity, and good thermal shock resistance. They are ideal ablation structural materials for throat linings of solid rocket motors. The rapid oxidation of carbon / carbon composite throat lining in the high temperature aerobic environment above 500 ℃ will lead to the rapid attenuation of its mechanical properties. If the throat lining is severely ablated during operation, it will be difficult to maintain a stable aerodynamic shape, whi...

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