阅读说明：本技术 一种高体积分数陶瓷增强铝基复合材料制备方法 (Preparation method of high-volume-fraction ceramic-reinforced aluminum-based composite material ) 是由 范语楠 范才河 阳建君 欧玲 严红革 何世文 郑东升 于 2020-05-21 设计创作，主要内容包括：本发明公开了一种高体积分数陶瓷增强铝基复合材料制备方法,以铝合金薄带和陶瓷颗粒为原材料,经预处理、加热熔融、雾化沉积制备而成。本发明可制备任意高体积分数的陶瓷颗粒增强铝基复合材料,陶瓷颗粒在铝基复合材料中分布均匀,能显著降低铝基复合材料的热膨胀系数、提高复合材料的综合力学性能。本发明采用沉积成型,通过控制沉积距离和铝丝输送速率,即可调整陶瓷增强铝基复合材料的尺寸,制备出近净尺寸的陶瓷增强铝基复合材料半成品,可应用于工业生产。(The invention discloses a preparation method of a high volume fraction ceramic reinforced aluminum matrix composite, which takes an aluminum alloy thin strip and ceramic particles as raw materials and is prepared by pretreatment, heating melting and atomization deposition. The invention can prepare any ceramic particle reinforced aluminum matrix composite with high volume fraction, the ceramic particles are uniformly distributed in the aluminum matrix composite, the thermal expansion coefficient of the aluminum matrix composite can be obviously reduced, and the comprehensive mechanical property of the composite can be improved. The invention adopts deposition molding, can adjust the size of the ceramic reinforced aluminum matrix composite by controlling the deposition distance and the aluminum wire conveying speed, prepares a ceramic reinforced aluminum matrix composite semi-finished product with near net size, and can be applied to industrial production.)

1. A preparation method of a high volume fraction ceramic reinforced aluminum matrix composite is characterized in that an aluminum alloy thin strip and ceramic particles are used as raw materials, and the preparation method comprises the following steps:

s1, pretreatment: wrapping ceramic particles in the aluminum alloy thin strip, and welding the sealing position of the aluminum alloy thin strip to prepare an aluminum wire filled with the ceramic particles;

s2, heating and melting: conveying the aluminum wire prepared in the step S1 to an induction heater, heating and melting to form molten droplets wrapping the ceramic particles;

s3, atomization and deposition: and (4) atomizing the molten droplets in the step S2 into micro-nano aluminum alloy droplets and ceramic particles by using high-pressure nitrogen, and co-depositing to form the ceramic particle reinforced aluminum matrix composite.

2. The method of preparing a high volume fraction ceramic reinforced aluminum matrix composite as claimed in claim 1 wherein the volume fraction of ceramic particles in the raw material is greater than 40%.

3. The method for preparing the high-volume-fraction ceramic-reinforced aluminum-based composite material as claimed in claim 2, wherein the volume ratio of the ceramic particles to the aluminum alloy thin strip is 45-65: 35-55.

4. The method of claim 1, wherein the ceramic particles comprise SiC, TiC, MgO, Al₂O₃Any one or more of.

5. The method for preparing a high volume fraction ceramic reinforced aluminum matrix composite according to claim 1, wherein the temperature of the induction heating in step S2 is 800 to 1000 ℃.

6. The method for preparing a high volume fraction ceramic reinforced aluminum matrix composite according to claim 1, wherein the high pressure nitrogen gas atomizes the molten droplets from the periphery of the molten droplets in step S3.

7. The preparation method of the high volume fraction ceramic reinforced aluminum matrix composite according to claim 6, wherein the pressure of the high pressure nitrogen is 2-5 MPa, and the temperature is-10 ℃ to-20 ℃.

8. The method for preparing a high volume fraction ceramic-reinforced aluminum-based composite material according to claim 1, wherein the deposition distance of the ceramic particle-reinforced aluminum-based composite material in step S3 is 200 to 300 mm.

9. The preparation method of the high volume fraction ceramic reinforced aluminum matrix composite material as claimed in claim 1, wherein the aluminum alloy thin strip is 2024 aluminum alloy, and the 2024 aluminum alloy comprises the following components by mass percent: 4% of Cu, 1.8% of Mg, 0.4% of Mn and the balance of Al.

10. A high volume fraction ceramic reinforced aluminum matrix composite obtained by the preparation method according to any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of aluminum-based composite materials, in particular to a preparation method of a high-volume-fraction ceramic reinforced aluminum-based composite material.

Background

The ceramic reinforced aluminum-based composite material generally has excellent comprehensive properties such as low density, high specific stiffness, low expansion, high heat conductivity and the like, and is expected to become a novel structural material following aluminum alloy and titanium alloy. However, with the rapid development of aerospace technologies and cosmic detection technologies, the ceramic reinforced aluminum matrix composite with a low volume fraction (5-30%) is difficult to meet the use requirements of severe space environments, such as various structural members, electronic packages, measuring instruments, optical devices, sensitive elements, satellite lens barrels and the like widely applied in aerospace, and requires a lower thermal expansion coefficient, a better thermal conductivity coefficient, a higher elastic modulus and a more excellent comprehensive mechanical property. In order to meet the requirements, the development of the ceramic reinforced aluminum matrix composite material with high volume fraction (more than 40%) and excellent mechanical property is a feasible approach.

At present, the prior preparation method of the high volume fraction ceramic reinforced aluminum matrix composite material mainly comprises an infiltration method, a casting method and the like, wherein the infiltration method is to infiltrate aluminum alloy into porous reticular ceramic particle precast blocks by means of extrusion infiltration or air pressure infiltration; the casting method is to add the reinforcing ceramic particles to a fully or partially melted matrix metal melt which is stirred at high speed and then cast into a composite material. The two methods have the main defects that the ceramic reinforcement is difficult to disperse uniformly, has poor mechanical property, is difficult to realize low thermal expansion coefficient and higher thermal conductivity coefficient, and has high processing difficulty and high cost.

Disclosure of Invention

The invention aims to provide a preparation method of a high-volume-fraction ceramic-reinforced aluminum-based composite material aiming at the defects in the prior art, an aluminum alloy thin strip is used for wrapping ceramic particles in advance, the production process is simplified, molten aluminum alloy liquid drops tightly wrap the ceramic particles, and the deposition efficiency and the dispersion uniformity of the ceramic particles can be effectively improved.

The invention also aims to provide the high volume fraction ceramic reinforced aluminum matrix composite material obtained by the preparation method, the ceramic particles are uniformly distributed in the aluminum matrix, and the reinforcing effect is good.

The purpose of the invention is realized by the following technical scheme:

a preparation method of a high volume fraction ceramic reinforced aluminum matrix composite takes an aluminum alloy thin strip and ceramic particles as raw materials, and comprises the following steps:

s1, pretreatment: wrapping ceramic particles in the aluminum alloy thin strip, and welding the sealing position of the aluminum alloy thin strip to prepare an aluminum wire filled with the ceramic particles;

s2, heating and melting: conveying the aluminum wire prepared in the step S1 to an induction heater, heating and melting to form molten droplets wrapping the ceramic particles;

s3, atomization and deposition: and (4) atomizing the molten droplets in the step S2 into micro-nano aluminum alloy droplets and ceramic particles by using high-pressure nitrogen, and co-depositing to form the ceramic particle reinforced aluminum matrix composite.

The aluminum alloy thin strip is used for wrapping ceramic particles and then is melted to form molten liquid drops wrapping the ceramic particles, the molten liquid drops and the ceramic particles are formed through high-pressure nitrogen atomization, and then the ceramic particle reinforced aluminum matrix composite material is formed through deposition; the ceramic particles are uniformly distributed in the aluminum matrix composite material, and agglomeration is not generated.

Further, the volume ratio of the ceramic particles in the raw material is more than 40%.

Further, the volume ratio of the ceramic particles to the aluminum alloy thin strip is 45-65: 35-55.

Further, the ceramic particles comprise SiC, TiC, MgO, Al₂O₃Any one or more of.

Further, the temperature of the induction heating in the step S2 is 800-1000 ℃.

Further, the high-pressure nitrogen gas atomizes the molten droplets from the peripheries of the molten droplets in step S3, respectively.

Further, the pressure of the high-pressure nitrogen is 2-5 MPa, and the temperature is-15 ℃ to-20 ℃.

The invention uses high-pressure nitrogen to atomize the molten liquid drops to form micro-nano aluminum alloy liquid drops and ceramic particles, and the aluminum alloy liquid drops are rapidly cooled under the action of low-temperature nitrogen to obtain the aluminum alloy matrix material with fine grains and uniform structure.

Further, the deposition distance of the ceramic particle reinforced aluminum matrix composite in the step S3 is 200-300 mm.

Further, the aluminum alloy thin strip is 2024 aluminum alloy, and the 2024 aluminum alloy comprises the following components in percentage by mass: 4% of Cu, 1.8% of Mg, 0.4% of Mn and the balance of Al.

A high volume fraction ceramic reinforced aluminum matrix composite material obtained according to the preparation method.

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

the method has low requirement on equipment, and can prepare any ceramic particle reinforced aluminum matrix composite material with high volume fraction. Various ceramic reinforcing particles can be added simultaneously in the preparation process, and the ceramic particles are uniformly distributed in the aluminum matrix composite material, so that a good reinforcing effect can be achieved; the functional material with low thermal expansion coefficient, high thermal conductivity coefficient, high elastic modulus and other special properties can be prepared by designing the types and components of the ceramic reinforced particles.

In the preparation process, the ceramic particles and the aluminum matrix are fully metallurgically bonded, the oxide at the interface of the ceramic particles and the aluminum matrix is less, the impurities are less, and the ceramic particle strengthening effect is good.

In the preparation process, under the protection of high-pressure nitrogen, the aluminum alloy liquid is not easy to oxidize; meanwhile, the cooling rate is high, the aluminum alloy matrix obtained after deposition is fine in crystal grains and uniform in structure, and the strength and the plasticity of the aluminum matrix composite can be effectively improved. The invention adopts deposition molding, can adjust the size of the ceramic reinforced aluminum matrix composite by controlling the deposition distance and the aluminum wire conveying speed, prepares a ceramic reinforced aluminum matrix composite semi-finished product with near net size, and can be applied to industrial production.

Drawings

FIG. 1 is a schematic view showing the structure of an apparatus for producing a high volume fraction ceramic-reinforced aluminum-based composite material in example 1;

wherein 1 is an aluminum wire wrapping ceramic particles, 2 is a conveying device, 3 is an induction heater, 4 is high-pressure nitrogen, 5 is molten liquid drops, 6 is ceramic particles, 7 is aluminum alloy liquid drops, and 8 is a ceramic reinforced aluminum matrix composite material.

Detailed Description

In order to facilitate understanding of the present invention, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the following specific examples.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.