Anti-ablation layer on graphite surface and preparation method thereof

Abstract

The invention discloses a graphite surface anti-ablation layer and a preparation method thereof. The graphite surface anti-ablation layer is composed of a graphite surface matrix and ultra-high temperature ceramic columns distributed in the graphite surface matrix. The preparation method includes (1) preparing graphite with a smooth surface; (2) preparing graphite with holes in the surface layer; (3) manufacturing graphite matrix with holes in the surface layer; (4) preparing alloy raw materials and obtaining alloys by melting; Melt to obtain an alloy melt, then contact the graphite matrix with holes on the surface with the alloy melt, so that the alloy melt penetrates into the surface pores of the graphite matrix and reacts with the graphite to obtain a graphite sample with an ultra-high temperature ceramic column; (6 ) to separate the graphite sample from the alloy melt, and obtain an anti-ablation layer on the graphite surface after heat preservation. The thickness and composition of the anti-ablation layer on the graphite surface of the present invention are easy to control, can be prepared in situ on the graphite surface, and the preparation method has 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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