阅读说明：本技术 一种铈改性抗氧化陶瓷基复合材料及其制备方法 (Cerium-modified antioxidant ceramic matrix composite and preparation method thereof ) 是由 陈昊然 于艺 杨良伟 李晓东 刘伟 张宝鹏 刘俊鹏 于新民 裴雨辰 于 2021-10-09 设计创作，主要内容包括：本发明提供了一种铈改性抗氧化陶瓷基复合材料及其制备方法,应用于航空航天材料技术领域；该制备方法包括：将金属铈在真空环境下加热至蒸发温度,然后对陶瓷基复合材料进行真空蒸镀,得到包含金属铈层的所述抗氧化陶瓷基复合材料；其中,所述金属铈层的厚度为1-5μm。本发明制备的氧化陶瓷基复合材料具有优异的高温环境下的抗氧化性；本发明通过真空退火的方式使经过高温氧化后的陶瓷基复合材料恢复储氧能力。(The invention provides a cerium modified antioxidant ceramic matrix composite and a preparation method thereof, which are applied to the technical field of aerospace materials; the preparation method comprises the following steps: heating the metal cerium to an evaporation temperature in a vacuum environment, and then carrying out vacuum evaporation on the ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material containing the metal cerium layer; wherein the thickness of the metal cerium layer is 1-5 μm. The oxide ceramic matrix composite material prepared by the invention has excellent oxidation resistance in a high-temperature environment; the invention recovers the oxygen storage capacity of the ceramic matrix composite material after high-temperature oxidation in a vacuum annealing mode.)

1. The preparation method of the cerium modified antioxidant ceramic matrix composite is characterized by comprising the following steps of:

heating the metal cerium to an evaporation temperature in a vacuum environment, and then carrying out vacuum evaporation on the ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material containing the metal cerium layer; wherein the thickness of the metal cerium layer is 1-5 μm.

2. The method of claim 1, wherein:

placing the oxidation-resistant ceramic matrix composite material at the temperature of 1000-1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 2-20%, and further comprising the following steps:

carrying out vacuum annealing treatment on the antioxidant ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material again;

wherein the content of the metal cerium in the metal cerium layer of the obtained antioxidant ceramic matrix composite material is 55-70%.

3. The method of claim 2, wherein:

the temperature of the vacuum annealing is 200-1400 ℃;

the time of the vacuum annealing is 0.5-1 h; and/or

The vacuum pressure of the vacuum annealing is 1 x 10^-11-1×10^-2mbar。

4. The method of claim 1, wherein:

before the ceramic matrix composite material is subjected to vacuum evaporation, the method also comprises the step of pretreating the ceramic matrix composite material: at a vacuum pressure of 1X 10^-8-1×10^-5mbar, and the temperature is 400-700 ℃ for 10-30 min.

5. The method of claim 1, wherein:

the purity of the metal cerium is more than or equal to 99 percent;

the particle size of the metal cerium is 200nm-1 mu m.

6. The method of claim 1, wherein:

the vacuum pressure of the vacuum environment is 1 x 10^-11-1×10^-2mbar; and/or

The vacuum pressure of the vacuum evaporation is 1 multiplied by 10^-11-1×10^-2mbar。

7. The method of claim 1, wherein:

the method for heating the metal cerium to the evaporation temperature in the vacuum environment comprises the following substeps:

the metal cerium is placed in an evaporation source, and then 0.5-2A current and 500-1000V voltage are applied to the evaporation source to heat the evaporation source to the evaporation temperature.

8. The method of claim 1, wherein:

the vacuum evaporation adopts a molecular beam epitaxial growth method; and/or

The evaporation temperature is 900-1400 ℃.

9. The method of claim 1, wherein:

the evaporation time of the vacuum evaporation is 20-50 h.

10. An oxidation-resistant ceramic matrix composite, characterized in that it is obtained by the preparation method according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of aerospace materials, in particular to a preparation method of a cerium modified antioxidant ceramic matrix composite material.

Background

The ceramic matrix composite is a key strategic material, which not only utilizes the advantages of high temperature resistance, low density, high specific strength, high specific modulus, oxidation resistance and the like of the ceramic material, but also solves the problems of poor toughness and poor thermal shock resistance of the ceramic material by a fiber toughening method, so that the ceramic matrix composite is widely applied to spacecraft structural members, such as aircraft engine combustion chambers, tail nozzles and the like. With the increasing research and development investment on high-mach-number aircrafts, researchers have made higher requirements on the high-temperature resistance, oxidation resistance and ablation resistance of the ceramic matrix composite, and the existing ceramic matrix composite system can not meet the requirements of the high-mach-number aircrafts on materials gradually. The design of the existing high-temperature-resistant anti-oxidation material mainly depends on the structure of the material, and the requirement of the current aerospace technology on the high-temperature resistance and the anti-oxidation of the ceramic matrix composite material cannot be met only by depending on the structure of the material. Therefore, how to improve the oxidation resistance of the ceramic matrix composite is a problem which needs to be solved urgently at present.

Disclosure of Invention

The embodiment of the invention provides a cerium-modified antioxidant ceramic matrix composite and a preparation method thereof, which can provide an antioxidant ceramic matrix composite, which can still maintain excellent inoxidizability at the temperature of 1000-1600 ℃, and can recover the inoxidizability through vacuum annealing treatment after oxidation.

In a first aspect, the present invention provides a method for preparing a cerium modified antioxidant ceramic matrix composite, comprising the steps of:

heating the metal cerium to an evaporation temperature in a vacuum environment, and then carrying out vacuum evaporation on the ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material containing the metal cerium layer; wherein the thickness of the metal cerium layer is 1-5 μm.

Preferably, the anti-oxidation ceramic matrix composite material is placed at the temperature of 1000-1600 ℃ until the content of the metal cerium in the metal cerium layer of the anti-oxidation ceramic matrix composite material is 2-20%, and the method further comprises the following steps:

carrying out vacuum annealing treatment on the antioxidant ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material again;

wherein the content of the metal cerium in the metal cerium layer of the obtained antioxidant ceramic matrix composite material is 55-70%.

Preferably, the temperature of the vacuum annealing is 200-1400 ℃;

the time of the vacuum annealing is 0.5-1 h.

Preferably, the vacuum pressure of the vacuum annealing is 1 × 10^-11-1×10^-2mbar。

Preferably, before the vacuum evaporation of the ceramic matrix composite material, the method further comprises the step of pretreating the ceramic matrix composite material: at a vacuum pressure of 1X 10^-8-1×10^-5mbar, and the temperature is 400-700 ℃ for 10-30 min.

Preferably, the purity of the metal cerium is more than or equal to 99 percent;

the particle size of the metal cerium is 200nm-1 mu m.

Preferably, the vacuum pressure of the vacuum environment is 1 × 10^-11-1×10^-2mbar。

Preferably, the vacuum pressure of the vacuum evaporation is 1 × 10^-11-1×10^-2mbar。

Preferably, the heating of the cerium metal to the evaporation temperature in the vacuum environment comprises the following substeps:

the metal cerium is placed in an evaporation source, and then 0.5-2A current and 500-1000V voltage are applied to the evaporation source to heat the evaporation source to the evaporation temperature.

Preferably, the vacuum evaporation adopts a molecular beam epitaxy growth method.

Preferably, the evaporation temperature is 900-.

Preferably, the evaporation time of the vacuum evaporation is 20-50 h.

In a second aspect, the invention provides an antioxidant ceramic matrix composite prepared by the preparation method of any one of the first aspect.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) the invention takes rare earth metal cerium (Ce) as a target source, the rare earth element Ce has multiple valence states (such as 0, +3, +4 valence) and oxide form (Ce)₂O₃、CeO₂) The strong capacity of storing and releasing oxygen can be generated by the transition between different valence states of the rare earth element Ce. Therefore, the rare earth element Ce can effectively absorb and convert oxygen and prevent the oxygen from permeating into the composite material to cause failure of the carbon fiber, so that the oxidation resistance of the composite material is improved. In order to ensure that Ce introduced into the ceramic matrix composite has uniform thickness, uniform dispersion and low porosity (1-5%), the method solves the problem in the experimental technology. The metal cerium layer can be obtained more efficiently in a vacuum evaporation mode, the metal cerium layer forms a compact protective layer on the outer surface layer of the ceramic matrix composite material, oxygen can be effectively prevented from entering the inside of the ceramic matrix composite material, and meanwhile, the metal cerium in the metal cerium layer can absorb the oxygen to form cerium oxide, so that the purpose of oxidation resistance is achieved.

(2) The preparation process of the invention selects a high vacuum environment, which can ensure that the metal cerium can be evaporated on the surface of the ceramic matrix composite material at the temperature of 900 plus one year 1400 ℃, and simultaneously, part of the metal cerium enters the interior of the ceramic matrix composite material in the evaporation process, thereby further improving the oxidation resistance of the ceramic matrix composite material, and the oxidation resistance ceramic matrix composite material prepared by the invention can work at the high temperature environment of 1000 plus one year 1600 ℃;

(3) the invention adopts a vacuum annealing mode to ensure that the oxidation resistance is generated after the high-temperature environment of 1000-1600 DEG CThe oxidation-resistant ceramic matrix composite material recovers the oxidation resistance, and the main component of the metal cerium layer of the oxidation-resistant ceramic matrix composite material after oxidation is Ce₂O₃、CeO₂During annealing, cerium oxide (Ce)₂O₃、CeO₂) Will release oxygen and convert into metal cerium; after the vacuum annealing treatment, the content of the metal cerium is increased to 55-70%, and the oxidation resistance of the ceramic matrix composite material before high-temperature oxidation is recovered.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer and more complete, the technical solutions in the embodiments of the present invention will be described below in conjunction with the embodiments of the present invention, and it is obvious that the described embodiments are a part of the embodiments of the present invention, but not all embodiments, and all other embodiments obtained by a person of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention.

The invention provides a preparation method of a cerium modified antioxidant ceramic matrix composite, which comprises the following steps:

heating the metal cerium to an evaporation temperature in a vacuum environment, and then carrying out vacuum evaporation on the ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material containing the metal cerium layer; the thickness of the metal cerium layer is 1-5 μm (for example, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm or 5 μm).

According to some preferred embodiments, the method further comprises the following steps of placing the oxidation-resistant ceramic matrix composite at 1000-:

carrying out vacuum annealing treatment on the antioxidant ceramic matrix composite material to obtain the antioxidant ceramic matrix composite material again;

wherein the content of the metal cerium in the metal cerium layer of the recovered oxidation-resistant ceramic matrix composite material is 55-70% (for example, 55%, 60%, 65% or 70%).

According to some preferred embodiments, the temperature of the vacuum annealing is 200-.

According to some preferred embodiments, the vacuum annealing time is 0.5 to 1h (e.g. may be 0.5h, 0.6h, 0.7h, 0.8h, 0.9h or 1 h).

According to some preferred embodiments, the vacuum pressure of the vacuum annealing is 1 × 10^-11-1×10^-2mbar (which may be, for example, 1X 10^-11mbar、1×10^-10mbar、1×10^-9mbar、1×10^-8mbar、1×10^-7mbar、1×10^-6mbar、1×10^-5mbar、1×10^-4mbar、1×10^-3mbar or 1 x 10^-2mbar)。

In the invention, after the anti-oxidation ceramic matrix composite material works at 1600 ℃, the metal cerium in the metal cerium layer of the anti-oxidation ceramic matrix composite material is oxidized, and the main component of the cerium oxide after high-temperature oxidation is Ce₂O₃、CeO₂When the content of the metal cerium is reduced to 0-20%, the oxidation resistance is lost, and the oxidation resistance of the oxidation-resistant ceramic matrix composite material can be recovered through vacuum annealing treatment, so that the repeated recycling of the oxidation-resistant ceramic matrix composite material is realized.

According to some preferred embodiments, before the vacuum evaporation of the ceramic matrix composite material, the method further comprises the step of pretreating the ceramic matrix composite material: at a vacuum pressure of 1X 10^-8-1×10^-5mbar (which may be, for example, 1X 10^-8mbar、1×10^-7mbar、1×10^-6mbar or 1 x 10^-5mbar) at a temperature of 400 ℃ and 700 ℃ (for example, 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, 650 ℃ or 700 ℃) for 10-30min (for example, 10min, 15min, 20min, 25min or 30 min).

In the invention, the ceramic matrix composite material is firstly annealed at high temperature (400-700 ℃) in an ultrahigh vacuum environment, so that surface impurities can be removed to increase the exposed surface active sites.

According to some preferred embodiments, the purity of the metallic cerium is 99% or more; the particle size of the metallic cerium is 200nm to 1 μm (for example, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm or 1 μm may be used).

According to some more preferred embodiments, the cerium metal is in the form of a powder or foil. Specifically, the cerium metal is pressed into a foil shape, so that the uniform dispersity of the cerium metal can be ensured, generally speaking, the uniformity is better, and the oxidation resistance of the subsequently prepared composite material is better.

According to some preferred embodiments, the vacuum pressure of the vacuum environment is 1 × 10^-11-1×10^-2mbar。

According to some preferred embodiments, the vacuum pressure of the vacuum evaporation is 1 × 10^-11-1×10^-2mbar。

In addition, 1X 10^-11-1×10^-2mbar can be 1 × 10^-11mbar to 1 x 10^-2Any value in the mbar range, for example, may be 1X 10^-11mbar、1×10^-10mbar、1×10^-9mbar、1×10^-8mbar、1×10^-7mbar、1×10^-6mbar、1×10^-5mbar、1×10^-4mbar、1×10^-3mbar or 1 x 10^-2mbar。

According to some preferred embodiments, the heating of the cerium metal to the evaporation temperature in the vacuum environment comprises the following sub-steps:

placing the metal cerium in a crucible of an evaporation source, placing the crucible in a cavity of a metal epitaxial device, and passing through a vacuum pump set (such as a mechanical pump and a molecule)Pump, ion pump, etc.) to obtain high vacuum environment with vacuum pressure of 1 × 10^-11-1×10^-2mbar, and applying a current of 0.5-2A (such as 0.5A, 1A, 1.5A or 2A) and a voltage of 500-1000V (such as 500V, 600V, 700V, 800V, 900V or 1000V) to the evaporation source to heat the evaporation source to the evaporation temperature.

According to some preferred embodiments, the vacuum evaporation is performed by molecular beam epitaxy.

It should be noted that, in the prior art, in the process of introducing the rare earth metal Ce, a solution impregnation method is generally used, which is not only inefficient, but also prone to agglomeration, and thus may affect the final oxidation resistance of the composite material. According to the invention, the rare earth metal Ce layer is constructed on the surface of the ceramic matrix composite by an ultrahigh vacuum evaporation method, so that the uniform dispersion of metal Ce can be ensured, the uniform thickness of the metal layer can be ensured, and the low porosity (1-5%) can be ensured, so that the ceramic matrix composite has more excellent oxidation resistance.

It should be noted that the molecular beam epitaxy method is an atomic-scale processing technique, which is beneficial to realize accurate control of thickness, structure and composition, formation of a steep heterostructure, and the like, and has the advantages of low temperature of epitaxy growth and capability of avoiding pollution in a vacuum environment.

According to some preferred embodiments, the evaporation temperature is 900-1400 deg.C (which may be 900 deg.C, 1000 deg.C, 1100 deg.C, 1200 deg.C, 1300 deg.C or 1400 deg.C, for example), more preferably 1100 deg.C.

It should be noted that, in the prior art, high temperature of more than 1500 ℃ is usually required when metal Ce is evaporated, and in the present invention, the vacuum environment is adopted to further reduce the evaporation temperature, thereby reducing energy consumption. The temperature is greatly reduced to 900-1400 ℃ by evaporation in an ultrahigh vacuum environment.

According to some preferred embodiments, the ceramic matrix composite material is aligned with a metal evaporation source outlet for evaporation, and the vacuum evaporation time is 20-50h (for example, 20h, 25h, 30h, 35h, 40h, 45h or 50 h).

According to the invention, after the evaporation of the rare earth metal Ce, the ceramic matrix composite can form a 1-5 μm thick coating on the surface of the ceramic matrix composite, and a part of the metal Ce enters the ceramic matrix composite, so that the oxidation resistance of the ceramic matrix composite is improved.

The invention also provides a cerium-modified antioxidant ceramic matrix composite material prepared by the preparation method of the cerium-modified antioxidant ceramic matrix composite material.

The invention is further illustrated below with reference to specific examples. It is to be understood, however, that these examples are illustrative only and are not to be construed as limiting the scope of the present invention. The experimental procedures used in the following examples are all conventional procedures unless otherwise specified. Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

Example 1

(1) Preparing an antioxidant ceramic matrix composite material: the ceramic matrix composite is processed under vacuum pressure of 5 x 10^-6Annealing for 15min at mbar and 450 deg.C to pretreat the ceramic matrix composite. Foil-shaped cerium metal (purity: 99.9%, particle size of prepared foil-shaped cerium metal is 200nm) was placed in a crucible of an evaporation source and vacuum-pressurized at 1X 10^-10Heating the evaporation source to evaporation temperature (1100 deg.C) under mbar vacuum by applying 1.3A current and 700V voltage to the evaporation source, and aligning the outlet of the evaporation source with the ceramic matrix composite material (C)_fSiC ceramic matrix composite) at a vacuum pressure of 10^-10Carrying out evaporation plating of metal cerium under the mbar condition to obtain the anti-oxidation ceramic matrix composite material containing the metal cerium layer outside; wherein the oxidation resistant ceramic matrix composite is doped with metal cerium both externally and internally.

(2) Vacuum annealing of the antioxidant ceramic matrix composite: placing the oxidation-resistant ceramic matrix composite material at 1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 12%, and placing the oxidation-resistant ceramic matrix composite material at a vacuum pressure of 5 multiplied by 10^-7Carrying out vacuum annealing at the temperature of 500 ℃ in mbar to obtain the antioxidant ceramic matrix composite material with the antioxidant performance again; whereinAnd the content of the metal cerium in the obtained antioxidant ceramic matrix composite material is 65 percent.

(3) And (3) testing the oxidation resistance: the composite material is processed into a bending sample strip, and after static oxidation is carried out for 5 hours at 1600 ℃, the retention rate of the bending strength is up to 90.0 percent, and the weight loss rate is 6.2 multiplied by 10^-6g/min; after the static oxidation at 1600 ℃ for 5 hours for the second time, the bending strength retention rate is up to 87.1 percent, and the weight loss rate is 6.7 multiplied by 10^-6g/min。

Example 2

(1) Preparing an antioxidant ceramic matrix composite material: the ceramic matrix composite is processed under vacuum pressure of 5 x 10^-6Annealing for 15min at mbar and 470 deg.C to pretreat the ceramic matrix composite. Foil-shaped cerium metal (purity: 99.9%, particle size of prepared foil-shaped cerium metal is 200nm) was placed in a crucible of an evaporation source and vacuum-pressurized at 1X 10^-10Heating the evaporation source to evaporation temperature (1050 ℃) by applying 1.3A current and 700V voltage to the evaporation source in a vacuum environment of mbar, and aligning the outlet of the evaporation source with the ceramic matrix composite material (C)_f/SiC-ZrC ceramic matrix composite) under vacuum pressure of 1 x 10^-10Carrying out evaporation plating of metal cerium under the mbar condition to obtain the anti-oxidation ceramic matrix composite material containing the metal cerium layer outside; wherein the oxidation resistant ceramic matrix composite is doped with metal cerium both externally and internally.

(2) Vacuum annealing of the antioxidant ceramic matrix composite: placing the oxidation-resistant ceramic matrix composite material at 1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 13%, and placing the oxidation-resistant ceramic matrix composite material at a vacuum pressure of 1 × 10^-6Carrying out vacuum annealing at the temperature of 300 ℃ in mbar to obtain the antioxidant ceramic matrix composite material with the antioxidant performance again; wherein, the content of the metal cerium in the obtained anti-oxidation ceramic matrix composite material is 68 percent.

(3) And (3) testing the oxidation resistance: the composite material is processed into a bending sample strip, and after static oxidation is carried out for 5 hours at 1600 ℃, the retention rate of the bending strength is up to 87.5 percent, and the weight loss rate is 5.5 multiplied by 10^-6g/min; after the static oxidation at 1600 ℃ for 5 hours for the second time,the bending strength retention rate is as high as 75.1%, and the weight loss rate is 7.5 multiplied by 10^-6g/min。

Example 3

(1) Preparing an antioxidant ceramic matrix composite material: the ceramic matrix composite is processed under vacuum pressure of 5 x 10^-6Annealing for 15min at mbar and 500 deg.C, and pretreating ceramic matrix composite. Foil-shaped cerium metal (purity: 99.9%, particle size of prepared foil-shaped cerium metal is 200nm) was placed in a crucible of an evaporation source and vacuum-pressurized at 1X 10^-10Heating the evaporation source to evaporation temperature (1100 deg.C) under mbar vacuum by applying 1.3A current and 700V voltage to the evaporation source, and aligning the outlet of the evaporation source with the ceramic matrix composite material (C)_fSiC-TiC ceramic matrix composite) under the vacuum pressure of 1 multiplied by 10^-10Carrying out evaporation plating of metal cerium under the mbar condition to obtain the anti-oxidation ceramic matrix composite material containing the metal cerium layer outside; wherein the oxidation resistant ceramic matrix composite is doped with metal cerium both externally and internally.

(2) Vacuum annealing of the antioxidant ceramic matrix composite: placing the oxidation-resistant ceramic matrix composite material at 1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 11%, and placing the oxidation-resistant ceramic matrix composite material at a vacuum pressure of 1 × 10^-8Carrying out vacuum annealing at the temperature of 300 ℃ in mbar to obtain the antioxidant ceramic matrix composite material with the antioxidant performance again; wherein, the content of the metal cerium in the obtained anti-oxidation ceramic matrix composite material is 62 percent.

(3) And (3) testing the oxidation resistance: the composite material is processed into a bending sample strip, and after static oxidation is carried out for 5 hours at 1600 ℃, the retention rate of the bending strength is up to 87.0 percent, and the weight loss rate is 5.8 multiplied by 10^-6g/min; after the static oxidation at 1600 ℃ for 5 hours for the second time, the bending strength retention rate is up to 82.3 percent, and the weight loss rate is 6.9 multiplied by 10^-6g/min。

Example 4

(1) Preparing an antioxidant ceramic matrix composite material: the ceramic matrix composite is processed under vacuum pressure of 5 x 10^-6Annealing at mbar and 580 deg.C for 15min to compound ceramic matrixAnd (4) pretreating the material. Foil-shaped cerium metal (purity: 99.9%, particle size of prepared foil-shaped cerium metal is 200nm) was placed in a crucible of an evaporation source and vacuum-pressurized at 1X 10^-10Heating the evaporation source to evaporation temperature (1100 deg.C) under mbar vacuum by applying 1.3A current and 700V voltage to the evaporation source, and aligning the outlet of the evaporation source with the ceramic matrix composite material (C)_f/SiC-HfC ceramic matrix composite) at vacuum pressure of 1 x 10^-10Carrying out evaporation plating of metal cerium under the mbar condition to obtain the anti-oxidation ceramic matrix composite material containing the metal cerium layer outside; wherein the oxidation resistant ceramic matrix composite is doped with metal cerium both externally and internally.

(2) Vacuum annealing of the antioxidant ceramic matrix composite: placing the oxidation-resistant ceramic matrix composite material at 1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 14%, and placing the oxidation-resistant ceramic matrix composite material at a vacuum pressure of 1 × 10^-7Carrying out vacuum annealing at the temperature of 300 ℃ in mbar to obtain the antioxidant ceramic matrix composite material with the antioxidant performance again; wherein, the content of the metal cerium in the obtained anti-oxidation ceramic matrix composite material is 67 percent.

(3) And (3) testing the oxidation resistance: the composite material is processed into a bending sample strip, and after static oxidation is carried out for 5 hours at 1600 ℃, the bending strength retention rate is up to 82.0 percent, and the weight loss rate is 5.6 multiplied by 10^-6g/min; after the second static oxidation at 1600 ℃ for 5 hours, the bending strength retention rate is up to 79.8 percent, and the weight loss rate is 6.9 multiplied by 10^-6g/min。

Example 5

(1) Preparing an antioxidant ceramic matrix composite material: the ceramic matrix composite is processed under vacuum pressure of 5 x 10^-6Annealing for 15min at mbar and 650 deg.C to pretreat the ceramic matrix composite. Foil-shaped cerium metal (purity: 99.9%, particle size of prepared foil-shaped cerium metal is 200nm) was placed in a crucible of an evaporation source and vacuum-pressurized at 1X 10^-10Heating the evaporation source to evaporation temperature (1200 ℃) by applying a current of 1.3A and a voltage of 700V to the evaporation source in a vacuum environment of mbar, and aligning the outlet of the evaporation source with the ceramicCeramic-based composite material (C)_f/SiC-TaC ceramic matrix composite) under vacuum pressure of 1 x 10^-10Carrying out evaporation plating of metal cerium under the mbar condition to obtain the anti-oxidation ceramic matrix composite material containing the metal cerium layer outside; wherein the oxidation resistant ceramic matrix composite is doped with metal cerium both externally and internally.

(2) Vacuum annealing of the antioxidant ceramic matrix composite: placing the oxidation-resistant ceramic matrix composite material at 1600 ℃ until the content of the metal cerium in the metal cerium layer of the oxidation-resistant ceramic matrix composite material is 13%, and placing the oxidation-resistant ceramic matrix composite material at a vacuum pressure of 1 × 10^-8Carrying out vacuum annealing at mbar and 350 ℃ to obtain the antioxidant ceramic matrix composite material with the antioxidant performance again; wherein, the content of the metal cerium in the obtained anti-oxidation ceramic matrix composite material is 66%.

(3) And (3) testing the oxidation resistance: the composite material is processed into a bending sample strip, and after static oxidation is carried out for 5 hours at 1600 ℃, the bending strength retention rate is up to 79.0 percent, and the weight loss rate is 6.5 multiplied by 10^-6g/min; after the second static oxidation at 1600 ℃ for 5 hours, the bending strength retention rate is up to 77.3 percent, and the weight loss rate is 2.1 multiplied by 10^-5g/min。

Comparative example 1

To C not doped with metal cerium_fThe bending strength retention rate of the/SiC ceramic matrix composite material after static oxidation at 1600 ℃ for 5 hours is 37.0 percent, and the weight loss rate is 3.1 multiplied by 10^-4g/min; after the static oxidation at 1600 ℃ for 5 hours for the second time, the bending strength retention rate is up to 16.7 percent, and the weight loss rate is 6.5 multiplied by 10^-4g/min。

And (3) testing the oxidation resistance: the oxidation resistant ceramic matrix composite obtained in the above examples 1 to 5, comparative example 1 was processed into a bent sample bar, and tested for the first time: respectively testing the retention rate and the weight loss rate of the bending strength under the condition of static oxidation at 1600 ℃ for 5 h; and (3) testing for the second time: under the condition of continuing static oxidation for 5h at 1600 ℃, the retention rate and the weight loss rate of the bending strength are respectively tested, wherein the retention rate and the weight loss rate of the bending strength obtained by the test are shown in table 1.

TABLE 1

As can be seen from Table 1, compared with comparative example 1, the rare earth metal Ce doped ceramic matrix composite material of the present invention can effectively improve the oxidation resistance of the ceramic matrix composite material at high temperature (1600 ℃).

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention. The invention has not been described in detail and is in part known to those of skill in the art.