阅读说明：本技术 一种碳纤维增强陶瓷基复合材料及热解碳界面层制备方法 (Preparation method of carbon fiber reinforced ceramic matrix composite and pyrolytic carbon interface layer ) 是由 杨芳红 周长灵 姜凯 李涵 徐鸿照 刘瑞祥 张家路 于 2020-04-23 设计创作，主要内容包括：本发明公开了一种碳纤维增强陶瓷基复合材料及热解碳界面层制备方法,所述复合材料的组成包括碳纤维增强体、陶瓷基体、热解碳界面层,所述热解碳界面层位于碳纤维增强体与陶瓷基体之间并包覆于碳纤维增强体上,所述热解碳界面层采用化学气相沉积工艺在碳纤维增强体表面沉积热解碳形成。本发明一方面缓解了复合材料中增强体碳纤维与陶瓷基体之间的物理和化学性质的不匹配,另一方面保护了碳纤维在后续制备陶瓷基体中免受损害。采用本发明方法制备的热解碳界面层提高了复合材料的强度和韧性,同时使材料的断裂行为由脆性断裂变为韧性断裂。(The invention discloses a carbon fiber reinforced ceramic matrix composite and a preparation method of a pyrolytic carbon interface layer. The invention relieves the mismatching of physical and chemical properties between the reinforcement carbon fiber and the ceramic matrix in the composite material on one hand, and protects the carbon fiber from being damaged in the subsequent preparation of the ceramic matrix on the other hand. The pyrolytic carbon interface layer prepared by the method improves the strength and toughness of the composite material, and simultaneously changes the fracture behavior of the material from brittle fracture to ductile fracture.)

1. The utility model provides a carbon fiber reinforced ceramic matrix composite which characterized in that, composite's constitution includes carbon fiber reinforcement, ceramic matrix, pyrolytic carbon boundary layer is located between carbon fiber reinforcement and the ceramic matrix and cladding on carbon fiber reinforcement, pyrolytic carbon boundary layer adopts chemical vapor deposition technology at carbon fiber reinforcement surface deposit pyrolytic carbon formation.

2. The carbon fiber reinforced ceramic matrix composite according to claim 1, wherein: the carbon fiber reinforcement adopts a three-dimensional carbon fiber braided fabric with the volume fraction of the composite material being 20-40%.

3. The carbon fiber reinforced ceramic matrix composite according to claim 1 or 2, wherein: the thickness of the pyrolytic carbon interface layer is 100nm-10 mu m.

4. A preparation method of a pyrolytic carbon interface layer of a carbon fiber reinforced ceramic matrix composite is characterized by comprising the following steps:

step one

And putting the carbon fiber reinforcement into a high-temperature furnace to carry out glue removal treatment in a vacuum state.

Step two

And placing the obtained carbon fiber reinforcement into a chemical vapor deposition furnace for pyrolytic carbon interface layer deposition.

5. The method for preparing the pyrolytic carbon interface layer of the carbon fiber reinforced ceramic matrix composite according to claim 4, wherein the carbon fiber reinforcement is a three-dimensional carbon fiber woven fabric reinforcement woven by carbon fibers into a desired shape by a weaving process.

6. The method for preparing the pyrolytic carbon interface layer of the carbon fiber reinforced ceramic matrix composite according to claim 4, wherein the temperature of the gel removal treatment in the first step is 600-1200 ℃.

7. The method according to claim 4, wherein the pyrolytic carbon interface layer deposition process conditions in the second step comprise the following steps: the temperature is 600-1200 ℃, the carbon source gas is propane, the carrier gas is argon, the flow rate of the propane gas is 1.0-10.0L/min, the flow rate of the argon gas is 1.0-10.0L/min, the pressure in the furnace is 1.0-10.0KPa, and the deposition time is 10-100 h.

8. The method for preparing the pyrolytic carbon interface layer of the carbon fiber reinforced ceramic matrix composite according to claim 4 or 5, wherein the carbon fiber reinforcement is of a needle punched structure, a three-dimensional woven structure or a 2.5D woven structure.

9. The method for preparing the pyrolytic carbon interface layer of the carbon fiber reinforced ceramic matrix composite according to claim 7, wherein the method is used for obtaining the pyrolytic carbon interface layers with different thicknesses and structures by adjusting the process parameters including temperature, pressure, gas flow and deposition time.

Technical Field

The invention relates to the technical field of interface modification of carbon fiber reinforced ceramic matrix composites, and particularly provides a carbon fiber reinforced ceramic matrix composite and a preparation method of a pyrolytic carbon interface layer.

Background

The carbon fiber reinforced ceramic matrix composite is a composite material with carbon fibers as a reinforcement and ceramics as a matrix. By adding the high-temperature-resistant ceramic matrix, the carbon fiber reinforced ceramic matrix composite can be used as a high-temperature-resistant material. Compared with other high-temperature resistant materials, the carbon fiber reinforced ceramic matrix composite has the characteristics of light specific gravity, low thermal conductivity, low thermal expansion coefficient, chemical corrosion resistance, high strength, high hardness and the like, and becomes an ideal high-temperature structural material. However, the difference of physical and chemical properties between the carbon fiber reinforcement of the composite material and the ceramic matrix causes the problems of the mismatch of the thermal expansion coefficients and the mismatch of the microscopic lattices of the two. The interface between the two is susceptible to brittle fracture when stress is applied, resulting in a reduction in the strength and toughness of the composite.

Disclosure of Invention

The technical task of the invention is to provide a carbon fiber reinforced ceramic matrix composite and a preparation method of a pyrolytic carbon interface layer aiming at the problems, so as to solve the problem that the properties of a reinforcement and a matrix of the carbon fiber reinforced ceramic matrix composite are not matched.

The interface plays a role in transferring load, heat and the like in the composite material, and is also a concentrated area of cracks, defects and the like in the material fracture process, and the interface performance has obvious influence on the mechanical performance and the thermophysical performance of the composite material, so that the interface modification is an important way for improving the mechanical performance and the oxidation and ablation resistance of the composite material.

In order to achieve the purpose, the invention provides the following technical scheme:

the utility model provides a carbon fiber reinforced ceramic matrix composite, composite's constitution includes carbon fiber reinforcement, ceramic base, pyrolytic carbon interface layer is located between carbon fiber reinforcement and the ceramic base and cladding on carbon fiber reinforcement, pyrolytic carbon interface layer adopts chemical vapor deposition technology at carbon fiber reinforcement surface deposit pyrolytic carbon formation.

The carbon fiber reinforcement adopts a three-dimensional carbon fiber braided fabric with the volume fraction of the composite material being 20-40%.

The thickness of the pyrolytic carbon interface layer is 100nm-10 mu m.

A preparation method of a pyrolytic carbon interface layer of a carbon fiber reinforced ceramic matrix composite comprises the following steps:

step one

And putting the carbon fiber reinforcement into a high-temperature furnace to carry out glue removal treatment in a vacuum state.

Step two

And placing the obtained carbon fiber reinforcement into a chemical vapor deposition furnace for pyrolytic carbon interface layer deposition.

The carbon fiber reinforcement is a three-dimensional carbon fiber braided fabric reinforcement which is formed by braiding carbon fibers into a required shape by a braiding process.

The temperature of the glue discharging treatment in the first step is 600-1200 ℃.

The deposition process conditions of the pyrolytic carbon interface layer in the second step comprise the following contents:

the carbon fiber reinforcement is of a needle punched structure, a three-dimensional weaving structure or a 2.5D weaving structure.

The method obtains pyrolytic carbon interface layers with different thicknesses and structures by adjusting technological parameters including temperature, pressure, gas flow and deposition time.

Compared with the prior art, the preparation method of the carbon fiber reinforced ceramic matrix composite and the pyrolytic carbon interface layer has the following outstanding beneficial effects:

by designing the pyrolytic carbon interface layer, the invention effectively improves the interface bonding state and microstructure of the carbon fiber and the ceramic matrix, and greatly improves the mechanical property and thermophysical property of the composite material. The pyrolytic carbon is uniformly spread on the surface of the carbon fiber, has consistent thickness and fills the gullies on the surface layer of the carbon fiber.

The invention relieves the mismatching of physical and chemical properties between the reinforcement carbon fiber and the ceramic matrix in the composite material on one hand, and protects the carbon fiber from being damaged in the subsequent preparation of the ceramic matrix on the other hand. The pyrolytic carbon interface layer prepared by the method improves the strength and toughness of the composite material, and simultaneously changes the fracture behavior of the material from brittle fracture to ductile fracture.

Drawings

FIG. 1 is a scanning electron microscope image of the surface state of carbon fiber without vacuum degreasing treatment;

FIG. 2 is a scanning electron microscope image of the surface state of the carbon fiber after vacuum degreasing treatment;

FIG. 3 is a scanning electron micrograph of a pyrolytic carbon interface layer deposited on the surface of carbon fibers having a thickness of about 200 nm;

FIG. 4 is a scanning electron micrograph of a pyrolytic carbon interface layer deposited on the surface of carbon fibers having a thickness of about 1 μm.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.