Preparation method of copper-aluminum composite strip

Abstract

The invention provides a preparation method of a copper-aluminum composite strip, and belongs to the technical field of metal composite material preparation. According to the method, the copper foil and the aluminum foil are rolled to be cylindrical, then the copper-aluminum composite sheet is formed, and after vacuum annealing, the copper-aluminum composite strip is obtained through multi-pass cold rolling. According to the method, the copper foil and the aluminum foil are mutually wound to form the cylinder, and then the strip is prepared through cold rolling, so that the bonding area between copper and aluminum is greatly increased, the problem of sliding between copper and aluminum layers is solved, meanwhile, complex process steps such as welding and pretreatment are avoided, and a new path is provided for developing the high-performance copper-aluminum composite strip. According to the method, more than 40 layers of alternately-distributed copper-aluminum composite strips can be obtained through one-time rolling, multiple times of overlapping are not needed, and compared with an existing method, the method is more convenient and simpler.

Description

Technical Field

[0002] The invention belongs to the technical field of metal composite material preparation. Background Art

[0003] In today's society, with the rapid progress of economy and technology, the demand for material performance in many industries is increasing, especially in key fields such as aviation, aerospace, electronics, shipbuilding, energy and national defense. Traditional single materials can no longer meet all-round performance standards. In this context, in order to meet the industry's pursuit of economy and performance diversity, the advantages of composite materials are becoming increasingly prominent. Composite materials are a new material composed of two or more material components with different chemical and physical properties, which are optimized and combined through advanced material preparation technology. The design and manufacture of this material aims to obtain comprehensive performance that cannot be achieved by a single component material through the complementarity and correlation of the performance of each component. Among the many composite materials, metal layered composite materials occupy an important position, and their rolling composite technology has become a popular production process.

[0004] Copper-aluminum composite material is a new type of material made of copper and aluminum (or aluminum alloy) through a specific process. It combines the advantages of copper and aluminum, while overcoming the shortcomings of each material. It has the characteristics of light weight, high strength, high thermal conductivity, strong corrosion resistance, and strong impact resistance. It has been widely used in many fields such as electronics and electricity, machinery manufacturing, automobile manufacturing, and daily necessities. In addition, given the current situation of scarce copper resources and abundant aluminum resources in my country, promoting the "aluminum instead of copper" strategy can help alleviate the problem of overcapacity of aluminum in my country, and can also achieve resource complementarity and create significant economic value.

[0005] The traditional preparation process of copper-aluminum composite strips is to overlap two plates and then cold-roll them. During the process, due to the different ductility of copper and aluminum metals, sliding is likely to occur between the layers, resulting in problems such as reduced mechanical properties of the product. Currently available patent documents provide solutions such as welding the edges before rolling, or etching or modifying the bonding surfaces to increase the roughness. However, the above solutions increase the complexity of the process and increase the manufacturing cost. Summary of the invention

[0006] In order to solve the problems existing in the above-mentioned prior art, the present invention proposes a method for preparing a copper-aluminum composite strip, and the technical solution adopted is specifically as follows: A method for preparing a copper-aluminum composite strip comprises the following steps: 1) Select copper foil and aluminum foil with a thickness of 0.1~0.5 mm, clean the copper foil and aluminum foil, and remove impurities on the surface; 2) Stack the copper foil and aluminum foil together, and then roll them into a cylinder with a diameter of 8~10mm; 3) The copper foil and aluminum foil rolled into a cylindrical shape are pressed into a sheet on a hot press to obtain a copper-aluminum composite sheet with a thickness of 3-5 mm; 4) Place the copper-aluminum composite sheet in a vacuum annealing furnace and anneal it at 400-500°C for 1-3 hours with a vacuum degree of 1×10 -5 Pa to 1×10 -6 Between Pa; 5) cold rolling the annealed copper-aluminum composite sheet, with a deformation amount of 5-10% in each pass, and obtaining a copper-aluminum composite strip after multiple passes of rolling, wherein the copper-aluminum composite strip has a thickness of 0.1-0.5 mm.

[0007] Preferably, in step 1), the thickness of the copper foil and the aluminum foil is 0.1 mm.

[0008] Preferably, in step 1), alcohol is used to clean the copper foil and the aluminum foil.

[0009] Preferably, in step 2), the diameter of the cylinder is 10 mm.

[0010] Preferably, in step 3), the pressure at which the copper foil and the aluminum foil rolled into a cylindrical shape are pressed into a sheet on a press is 1 to 1.5 tons.

[0011] Preferably, in step 3), the thickness of the copper-aluminum composite sheet is 3 mm.

[0012] Preferably, the annealing treatment in step 4) is performed at a temperature of 500° C. and for a time of 1 h.

[0013] Preferably, the deformation amount of each cold rolling process in step 5) is 10%.

[0014] Beneficial effects of the present invention: The present invention is different from the traditional copper and aluminum plate composite rolling method. It uses copper foil and aluminum foil to wrap each other into a cylinder, and then prepare it into a strip through cold rolling. This method greatly increases the bonding area between copper and aluminum, solves the problem of sliding between copper and aluminum layers, and avoids the use of complex process steps such as welding and pretreatment, providing a new path for the development of high-performance copper-aluminum composite strips.

[0015] The method adopted by the present invention can obtain more than 40 layers of alternatingly distributed copper-aluminum composite strips through one rolling without the need for multiple stacking, which is more convenient and simpler than the existing method. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The morphology of copper-aluminum composite strip at different stages; Figure 2 Scanning electron microscope image of a cross section of a copper-aluminum composite strip; Figure 3 Energy spectrum image of the cross section of copper-aluminum composite strip. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is further explained and illustrated in the form of specific embodiments below.

[0018] Example 1 Copper foil and aluminum foil with a purity of 99.99%, a thickness of 0.1mm and a length of 20cm were selected.

[0019] 1) Use alcohol to clean the surface of copper foil and aluminum foil to remove impurities on the surface; 2) Stack the copper foil and aluminum foil together, and then roll them into a cylinder with a diameter of about 10mm; 3) Using a pressure of 1 ton, the copper foil and aluminum foil rolled into a cylindrical shape are pressed into a sheet on a hot press to obtain a copper-aluminum composite sheet with a thickness of 3 mm; 4) Place the copper-aluminum composite sheet in a vacuum annealing furnace and anneal it at 500°C for 1 hour with a vacuum degree of 1×10 -5 Pa to 1×10 -6 Between Pa; 5) The annealed copper-aluminum composite sheet is cold rolled, and the initial pressing amount and the deformation amount of each subsequent pass are 10%. After multiple passes of rolling, a composite strip with a thickness of 0.1 mm is finally obtained. Figure 1 As shown in d.

[0020] Figure 2 is the sample cross-section image, Figure 3 This is the energy spectrum image of the sample. From the image, we can observe that the overall thickness of the sample is about 100μm, and it can be clearly seen that the copper layer and the aluminum layer are alternately distributed. The number of layers is about 40, and the thickness of each layer is 0.1~20μm.

[0021] It should be understood that the application of the present invention is not limited to the above-mentioned embodiments. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for preparing a copper-aluminum composite strip, characterized in that: The method comprises the following steps: 1) Select copper foil and aluminum foil with a thickness of 0.1~0.5 mm, clean the copper foil and aluminum foil, and remove impurities on the surface; 2) Stack the copper foil and aluminum foil together, and then roll them into a cylinder with a diameter of 8~10mm; 3) The copper foil and aluminum foil rolled into a cylindrical shape are pressed into a sheet on a hot press to obtain a copper-aluminum composite sheet with a thickness of 3-5 mm; 4) Place the copper-aluminum composite sheet in a vacuum annealing furnace and anneal it at 400-500°C for 1-3 hours with a vacuum degree of 1×10 -5 Pa to 1×10 -6 Between Pa; 5) The annealed copper-aluminum composite sheet is cold-rolled, and the deformation amount of each pass is 5-10%. After multiple passes of rolling, a copper-aluminum composite strip is obtained, and the copper-aluminum composite strip has a thickness of 0.1-0.5 mm.

2. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: The thickness of the copper foil and the aluminum foil in step 1) is 0.1 mm.

3. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: In step 1), use alcohol to clean the copper foil and aluminum foil.

4. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: Step 2) The diameter of the cylinder is 10mm.

5. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: In step 3), the copper foil and aluminum foil rolled into a cylindrical shape are pressed into a sheet shape on a press machine with a pressure of 1 to 1.5 tons.

6. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: In step 3), the thickness of the copper-aluminum composite sheet is 3 mm.

7. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: In step 4), the annealing temperature is 500°C and the time is 1 hour.

8. The method for preparing the copper-aluminum composite strip according to claim 1, characterized in that: In step 5), the deformation amount of each cold rolling process is 10%.

Images