Graphite surface ablation-resistant layer and preparation method thereof

Abstract

The invention discloses a graphite surface ablation-resistant layer and a preparation method thereof. The graphite surface ablation-resistant layer is formed by a graphite surface layer substrate and ultrahigh-temperature ceramic columns distributed in the graphite surface layer substrate. The preparation method comprises the following steps: (1) graphite with a smooth surface is prepared; (2) graphite with a perforated surface is prepared; (3) a graphite substrate with perforated surface is prepared; (4) alloy raw materials are blended, and alloy is obtained by smelting; (5) the alloy is molten, such that alloy melt is obtained; the graphite substrate with perforated surface contacts the alloy melt, such that the alloy melt penetrates into the surface pores of the graphite substrate and is subjected to a reaction with graphite, and thus a graphite sample with ultrahigh-temperature ceramic columns is obtained; (6) the graphite sample is separated from the alloy melt; and through a temperature-maintaining process, the graphite surface ablation-resistant layer is obtained. The thickness and components of the graphite surface ablation-resistant layer provided by the invention are easy to control, and the graphite surface ablation-resistant layer can be prepared through in-situ preparation on the surface of graphite. The preparation method has the advantages of simple process, high efficiency and low cost.

Description

technical field [0001] The invention belongs to the field of ultra-high-temperature oxidation-ablation-resistant materials, and relates to an anti-ablation layer on a graphite surface and a preparation method thereof, in particular to an ultra-high-temperature ceramic modified high-temperature oxidation-resistant ablation layer on a graphite surface and a preparation method thereof. Background technique [0002] Graphite material has high melting point, high modulus, low density, excellent thermal shock resistance and corrosion resistance, and good thermal conductivity, and its mechanical properties at high temperatures are still stable and reliable. It has become an increasingly important high-temperature structural material. It is widely used in the fields of aviation, aerospace, metallurgy, machinery, nuclear energy and chemical industry. However, graphite easily reacts with oxidizing gases at temperatures above 400 °C, which significantly reduces its mechanical propertie...

AI Technical Summary

Problems solved by technology

However, in these methods of in-situ formation of protective layers, the thickness of the protective layer is very limited, and the graphite porosity is required to be large, and the mechanical properties of the graphite matrix will inevitably be damaged.

[0006] To sum up, the existing graphite anti-oxidation protection technology, whether it is to prepare a coating or form a protective layer in situ, has certain deficiencies, and it is necessary to develop a new type of graphite surface anti-high temperature oxidation ablation thick layer technology

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