阅读说明：本技术 一种氢气刻蚀的碳纳米管增强铜基复合材料的制备方法 (Preparation method of hydrogen-etched carbon nanotube reinforced copper-based composite material ) 是由 陶静梅 彭健 易健宏 鲍瑞 刘意春 李凤仙 李才巨 游昕 谈松林 于 2019-12-10 设计创作，主要内容包括：本发明公开一种氢气刻蚀的碳纳米管增强铜基复合材料的制备方法,属于复合材料制备领域。本发明所述方法先将碳纳米管进行酸化处理,其次,将纯铜粉球磨成片状,并将制得的酸化碳纳米管和片状铜粉混合球磨制备得到复合粉体,随后将复合粉体放入管式炉中并通入氢气,获得氢气刻蚀后的碳纳米管和铜粉的复合粉体,最后,通过放电等离子烧结工艺将所得的复合粉体制备成块体材料。本发明在铜的催化作用下,通过氢气对碳纳米管进行刻蚀处理,获得同时具备碳纳米管和石墨烯特征的混合结构,并将其作为增强体制备铜基复合材料,能有效增加碳纳米增强体和铜基体的接触面积,提高载荷转移效率,获得具有良好综合力学性能的铜基复合材料。(The invention discloses a preparation method of a hydrogen-etched carbon nanotube reinforced copper-based composite material, belonging to the field of composite material preparation. The method comprises the steps of firstly carrying out acidification treatment on a carbon nano tube, then, carrying out ball milling on pure copper powder into a sheet shape, mixing and ball milling the prepared acidified carbon nano tube and the sheet copper powder to obtain composite powder, then, putting the composite powder into a tube furnace, introducing hydrogen to obtain the composite powder of the carbon nano tube and the copper powder after hydrogen etching, and finally, preparing the obtained composite powder into a bulk material through a discharge plasma sintering process. According to the invention, under the catalytic action of copper, the carbon nano tube is etched by hydrogen to obtain a mixed structure with the characteristics of the carbon nano tube and graphene, and the mixed structure is used as a reinforcement to prepare the copper-based composite material, so that the contact area of the carbon nano reinforcement and a copper matrix can be effectively increased, the load transfer efficiency is improved, and the copper-based composite material with good comprehensive mechanical properties is obtained.)

1. A preparation method of a hydrogen-etched carbon nanotube reinforced copper-based composite material is characterized by comprising the following steps:

(1) acidizing the carbon nano tube: placing the carbon nano tube in acid liquor for ultrasonic dispersion treatment for 20-120 min, heating to 50-80 ℃, carrying out constant temperature treatment for 5-15 h, filtering, washing and drying to obtain a pretreated carbon nano tube;

(2) ball-milling treatment of pure copper powder: ball-milling pure copper powder into flake copper powder by adopting a high-energy ball-milling method;

(3) preparing composite powder: mixing and ball-milling the acidified carbon nano tube prepared in the step (1) and the flake copper powder prepared in the step (2) by adopting a high-energy ball milling method to obtain a carbon nano tube-copper composite powder body;

(4) hydrogen etching treatment of the composite powder: placing the composite powder prepared in the step (3) in a tube furnace, introducing hydrogen, heating to the hydrogen etching temperature, and preserving heat to obtain hydrogen-etched carbon nano tube-copper composite powder;

(5) sintering of the composite powder: and (4) performing spark plasma sintering or hot-pressing sintering on the composite powder prepared in the step (4) to obtain a compact block composite material.

2. The method for preparing a hydrogen-etched carbon nanotube-reinforced copper-based composite material according to claim 1, wherein the method comprises the following steps: the acid solution in the step (1) is a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, and the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is (3-4) to 1; the carbon nano tube is one or more of a single-wall carbon nano tube, a double-wall carbon nano tube and a multi-wall carbon nano tube, the purity of the carbon nano tube is not lower than 95%, and the diameter of the carbon nano tube is 50-100 nm.

3. The method for preparing a hydrogen-etched carbon nanotube-reinforced copper-based composite material according to claim 1, wherein the method comprises the following steps: in the step (2), the purity of the copper powder is not lower than 99%, the average particle size is 2-8 μm, and the conditions of the high-energy ball milling method are as follows: the ball-material ratio is 5-10: 1, the rotation speed of the ball mill is 200-400 r/min, and the ball milling is carried out for 5-10 hours.

4. The method for preparing a hydrogen-etched carbon nanotube-reinforced copper-based composite material according to claim 1, wherein the method comprises the following steps: in the step (3), the specific conditions of the mixing and ball milling are as follows: the ball-material ratio is 5-10: 1, the rotating speed of the ball mill is 100-200 r/min, the ball milling is carried out for 1-5 hours, and the volume percentage of the carbon nano tubes in the composite powder is 0.5-2.5%.

5. The method for preparing a hydrogen-etched carbon nanotube-reinforced copper-based composite material according to claim 1, wherein the method comprises the following steps: in the step (4), the flow rate of the hydrogen is 20-80 ml/min, the temperature of the hydrogen etching treatment is 850-1050 ℃, and the heat preservation time is 5-60 min.

6. The method for preparing a hydrogen-etched carbon nanotube-reinforced copper-based composite material according to claim 1, wherein the method comprises the following steps: in the step (5), the temperature of the spark plasma sintering or hot-pressing sintering treatment is 600-1000 ℃, the time of the spark plasma sintering or hot-pressing sintering treatment is 10-90 min, and the pressure of the spark plasma sintering or hot-pressing sintering is 10-80 MPa.

Technical Field

The invention relates to a preparation method of a hydrogen-etched carbon nanotube reinforced copper-based composite material, belonging to the technical field of composite material preparation.

Background

Carbon Nanotubes (CNTs) are a typical one-dimensional Carbon nanomaterial with a large aspect ratio, have a unique structure and excellent mechanical properties, have a tensile strength of 50-200 GPa, which is 100 times that of steel, but have a density of only 1/6 times that of steel, and have an elastic modulus of 1TPa, which is equivalent to that of diamond, which is about 5 times that of steel. Meanwhile, the carbon nano tube has excellent electric conduction and heat conduction performance and low thermal expansion coefficient, and can be used as an ideal reinforcement of a metal matrix composite material. However, due to poor wettability between the carbon nanotube and the metal matrix, the carbon nanotube reinforced metal matrix composite has the problems of easy agglomeration, low interface bonding strength between the carbon nanotube and the metal matrix, and the like in the preparation process of the carbon nanotube reinforced metal matrix composite. Graphene is a polymer made of carbon atoms in sp²The two-dimensional carbon nanomaterial composed of the hybrid orbit has excellent mechanical and electrical properties and has important application prospects in the field of composite materials. Compared with the carbon nano tube, the graphene with the two-dimensional structure has larger specific surface area, the effective contact area with the matrix is greatly increased when the graphene is used as a reinforcement of the composite material, the interface bonding strength with the matrix can be effectively improved, the load transfer efficiency is favorably improved, but the graphite prepared in a general commercial way has the advantages of large effective contact area with the matrix, high strength, high heat resistance, highThe length and width of the graphene are small, so that the graphene reinforced metal matrix composite is high in strength and poor in plasticity.

Graphene and carbon nanotubes are nanoscale carbon materials, and have characteristics of extremely large specific surface area, good conductivity, excellent mechanical properties and the like. The composite material can be used as a reinforcing phase to be added into a metal matrix to effectively improve the comprehensive performance of the composite material. According to the invention, the mixed structure reinforcement with the characteristics of graphene and carbon nano tubes is prepared by a hydrogen etching method under the catalysis of copper, the advantages of the carbon nano tubes and the graphene as the reinforcement can be effectively combined, the contact area of the reinforcement and a substrate is increased, the reinforcement has a larger length-diameter ratio, the load transfer and reinforcement functions can be fully exerted, and the composite material with good comprehensive mechanical properties is obtained.

Disclosure of Invention

The invention mainly provides a preparation method of a hydrogen-etched Carbon Nanotube (CNTs) reinforced copper-based composite material, which has novel design, more reasonable reinforcement structure and capability of obtaining the copper-based composite material with good comprehensive mechanical property; the preparation process is simple and convenient, the equipment is simple, the implementation is easy, and the specific implementation steps are as follows:

(1) acidizing the carbon nano tube: and (2) placing the carbon nano tube in acid liquor for ultrasonic dispersion treatment for 20-120 min, heating to 50-80 ℃, carrying out constant temperature treatment for 5-15 h, and filtering, washing and drying to obtain the pretreated carbon nano tube.

(2) Ball-milling treatment of pure copper powder: and ball-milling pure copper powder into flake copper powder by adopting a high-energy ball milling method.

(3) Preparing composite powder: and (3) mixing and ball-milling the acidified carbon nano tube prepared in the step (1) and the flake copper powder prepared in the step (2) by adopting a high-energy ball milling method to obtain the carbon nano tube-copper composite powder.

(4) Hydrogen etching treatment of the composite powder: and (4) placing the composite powder prepared in the step (3) in a tube furnace, introducing hydrogen, heating to a certain temperature, and preserving heat to obtain the hydrogen-etched carbon nano tube-copper composite powder.

(5) Sintering of the composite powder: and (4) performing spark plasma sintering or hot-pressing sintering on the composite powder prepared in the step (4) to obtain a compact block composite material.

Preferably, the acid solution in the step (1) is a mixed acid solution of concentrated sulfuric acid and concentrated nitric acid, and the volume ratio of the concentrated sulfuric acid to the concentrated nitric acid is (3-4): 1; the carbon nano tube is one or more of a single-wall carbon nano tube, a double-wall carbon nano tube and a multi-wall carbon nano tube, the purity of the carbon nano tube is not lower than 95%, and the diameter of the carbon nano tube is 50-100 nm.

Preferably, in the step (2) of the invention, the purity of the copper powder is not lower than 99%, the average grain diameter is 2-8 μm, and the conditions of the high-energy ball milling method are as follows: the ball-material ratio is 5-10: 1, the rotation speed of the ball mill is 200-400 r/min, and the ball milling is carried out for 5-10 hours.

Preferably, in step (3) of the present invention, the specific conditions of the mixing ball mill are as follows: the ball-material ratio is 5-10: 1, the rotating speed of the ball mill is 100-200 r/min, the ball milling is carried out for 1-5 hours, and the volume percentage of the carbon nano tubes in the composite powder is 0.5-2.5%.

Preferably, in the step (4), the flow rate of the hydrogen is 20-80 ml/min, the temperature of the hydrogen etching treatment is 850-1050 ℃, and the heat preservation time is 5-60 min.

Preferably, in the step (5) of the invention, the temperature of the spark plasma sintering or hot-press sintering treatment is 600-1000 ℃, the time of the spark plasma sintering or hot-press sintering treatment is 10-90 min, and the pressure of the spark plasma sintering or hot-press sintering is 10-80 MPa.

The excellent effects of the present invention:

(1) the method of the invention utilizes the catalytic action of copper, and carries out etching treatment on the carbon nano tube at high temperature through hydrogen to obtain the novel reinforcement with the characteristics of the carbon nano tube and the graphene, the mixed structure makes up the defect that the single carbon nano tube or the graphene is used as the reinforcement, and effectively combines the advantages of the carbon nano tube and the graphene as the reinforcement: the graphene structure can effectively increase the contact area between the reinforcement and the metal matrix, and improve the load transfer efficiency, so that the strength of the composite material is improved; the carbon nanotube structure has a larger length-diameter ratio, so that the tensile plasticity of the composite material can be effectively improved. Therefore, the carbon nano tube-graphene mixed structure after hydrogen etching is used as a reinforcement of the copper-based composite material, so that the composite material can obtain good comprehensive mechanical properties.

(2) According to the method, copper is used as a catalyst and is also a matrix of the composite material, and the etching of the carbon nano tube and the preparation of the composite powder are simultaneously completed through a one-step hydrogen etching process; the technological process is stable and reliable, the equipment is simple, and the method is easy to realize. In addition, the surface activity of the carbon nano tube can be improved by carrying out acidification treatment on the carbon nano tube, the wettability of the carbon nano tube with a copper matrix is improved, and the dispersion uniformity of the carbon nano tube in the copper matrix is improved; moreover, the spark plasma sintering technology can obtain compact block materials, and simultaneously effectively inhibit the growth of crystal grains, thereby further improving the mechanical property of the composite material.

Drawings

FIG. 1 is a process flow diagram of the method and composite material preparation of the present invention.

Fig. 2 is an SEM image of the original carbon nanotube-copper composite powder and the carbon nanotube-graphene-copper composite powder obtained under different cracking conditions.

Detailed Description

The invention will be described in more detail with reference to the following figures and examples, but the scope of the invention is not limited thereto.