C/SiC composite coating applied to surface of low-density carbon/carbon composite material and preparation process thereof

Abstract

The invention relates to a C / SiC composite coating applied to the surface of a low-density carbon / carbon composite material and a preparation process thereof. The composite coating consists of an inner hole sealing layer and an outer coating. The inner hole sealing layer is prepared from the raw materials in percentage by weight: 10-60% of silicon carbide powder, 1-25% of silicon powder, 0.05-8% of graphite powder, 1-10% of polyacrylonitrile ground carbon fiber and 40-80% of silica sol. The outer coating is prepared from the raw materials in percentage by weight: 10-30% of silicon carbide powder, 40-60% of resin, 30-70% of diluter and 1-6% of curing agent. The invention further comprises the preparation process of the low density C / SiC composite coating made of the carbon / carbon composite material. The C / SiC composite coating applied to the surface of the low-density carbon / carbon composite material provided by the invention is better in oxidation resistance, better in bonding force with a substrate material, compact in surface, free from crack and free from power fall.

Description

technical field [0001] The invention relates to thermal field material accessories for crystalline silicon growth equipment, in particular to a C / SiC composite coating on the surface of a low-density carbon / carbon composite thermal insulation material part and a preparation process thereof. Background technique [0002] Carbon / carbon composite materials have excellent properties such as high specific strength and specific modulus, high temperature resistance, corrosion resistance, fatigue resistance, creep resistance, good electrical conductivity and heat transfer performance, and small thermal expansion coefficient. Therefore, they are widely used in many fields. Applications. Low-density carbon / carbon composite materials are indispensable thermal insulation materials for monocrystalline silicon furnaces, polycrystalline silicon furnaces and high-temperature furnaces in many industries. The working temperature in monocrystalline silicon furnace and polycrystalline silicon ...

AI Technical Summary

Problems solved by technology

Although this method is simple in process, the bonding force between the coating and the substrate is poor, and powder is easy to fall off.

[0005] Chinese patent 200310115119.5 discloses a carbon / carbon composite anti-oxidation coating; Chinese patent 200510012730.4 discloses a method for preparing a high-temperature anti-oxidation coating on the surface of Ablation composite coating and preparation method, the above-mentioned patents are all preparation methods of relatively high-density carbon material surface coating, and are not suitable for the use requirements of silicon crystal furnaces that have strict requirements on the content of metal impurities

[0006] Chinese patent 200810079793.5 discloses a method for preparing silicon carbide coatings on carbon materials by electrophoretic deposition, which is complicated in process and high in cost