Preparation method of copper-aluminum composite board

Abstract

The invention provides a preparation method of a copper-aluminum composite board, which comprises the following steps: S1, carrying out rolling processing on a copper plate, and processing a plurality of embossments on the surface of the copper plate; s2, sequentially carrying out alkali washing, annealing treatment and acid washing on the rolled copper plate; s3, a hot-rolled aluminum plate is selected, and the surface of the aluminum plate is mechanically polished; s4, the floating convex face of the pickled copper plate and the mechanical polishing face of the aluminum plate are attached and assembled, mechanical combination of a copper-aluminum interface is achieved through single-pass large-rolling-reduction cold rolling, and a composite plate is obtained; and S5, the composite board is subjected to diffusion heat treatment, and the copper-aluminum composite board is prepared. According to the method, the copper-aluminum composite board with the high interface bonding strength can be manufactured through traditional equipment, and the method has the advantages of being low in production cost, simple in process and easy to industrially popularize.

Description

Technical Field

[0001] The invention relates to the technical field of preparation of metal layered composite materials, and in particular to a method for preparing a copper-aluminum composite plate. Background Art

[0002] Copper has excellent thermal conductivity, electrical conductivity, ductility and good corrosion resistance in certain media. It is the preferred material as an electrical conductor. However, my country's copper resources are in short supply and the cost is high. Aluminum is low in cost, low in density, light in weight, and has good electrical and thermal conductivity. The copper-aluminum composite plate prepared by combining copper plates and aluminum plates not only has the advantages of copper such as high strength, excellent electrical conductivity, good thermal conductivity and good wear resistance, but also has the characteristics of aluminum such as electrical conductivity, light weight, economy, good processing performance and strong corrosion resistance. It is widely used in heat dissipation, communications, energy, transportation and electricity.

[0003] The preparation methods of copper-aluminum composite plates mainly include explosion composite method, cast-roll composite method and rolling composite method. The explosion composite method uses the huge energy generated by the explosion of explosives to drive two metal plates to collide at a high speed, and uses high-speed impact to partially melt the interface metal to achieve composite. The process is simple, and the interface bonding strength of the prepared copper-aluminum composite plate is high. However, this method has problems such as environmental pollution and difficulty in continuous production. The cast-roll composite method is to completely melt the aluminum ingot into aluminum liquid, degas and filter it online after standing, and then contact it with the copper plate strip, and continuously roll it to form a copper-aluminum bimetallic composite plate strip. The cast-roll composite method improves production efficiency and product quality, and achieves energy saving and consumption reduction. However, it requires special equipment for degassing, filtering and rolling, and requires high skills of operators. The rolling composite method is divided into hot rolling and cold rolling. It is to tightly combine the two metal plates under the pressure of the rolling mill, and destroy the oxide layer and contamination layer at the metal contact interface to make the fresh metal combine under pressure. Hot rolling and cold rolling are relatively common production methods, which can achieve the production of copper-aluminum bimetallic composite plates with larger length and width. However, the rolling composite method has high requirements on equipment capacity, and the interface bonding strength of the prepared copper-aluminum composite plate is relatively low.

[0004] Therefore, in order to solve the problem of low interface bonding strength of copper-aluminum composite plates prepared by rolling composite method, it is of great significance to develop a rolling composite method for copper-aluminum composite plates with high interface bonding strength. Summary of the invention

[0005] According to the above-mentioned technical problem that the existing rolling composite technology is difficult to prepare a copper-aluminum composite plate with high interface bonding quality, a method for preparing a copper-aluminum composite plate is provided.

[0006] The technical means adopted by the present invention are as follows:

[0007] A method for preparing a copper-aluminum composite plate comprises the following steps:

[0008] S1, rolling the copper plate to form a plurality of reliefs on the surface of the copper plate;

[0009] S2, sequentially performing alkali washing, annealing and pickling on the copper plate after roller pressing;

[0010] S3, selecting a hot-rolled aluminum plate and mechanically grinding the surface of the aluminum plate;

[0011] S4, laminating the embossed surface of the pickled copper plate and the mechanically polished surface of the aluminum plate to form a blank, and performing single-pass cold rolling with a large reduction to achieve mechanical bonding at the copper-aluminum interface to obtain a composite plate;

[0012] S5. Performing diffusion heat treatment on the composite plate to prepare a copper-aluminum composite plate.

[0013] Furthermore, in the step S1, the embossment is in a shuttle shape, the angle between the direction of the shuttle-shaped embossment and the width direction of the copper plate is 45°, and the height of the shuttle-shaped embossment is 0.2-0.5 mm.

[0014] Furthermore, in step S2, the hardness of the copper plate after annealing is less than 100 HV.

[0015] Furthermore, in step S3, the angle between the mechanical grinding direction and the width direction of the aluminum plate is 45°, and the surface roughness Ra of the aluminum plate after grinding is greater than 2 μm.

[0016] Furthermore, in step S4, the pressing amount is 35%-42%.

[0017] Furthermore, in step S5, the heat treatment temperature is 300°C-350°C, and the insulation time is 6-8h.

[0018] Furthermore, in step S5, the thickness of the copper-aluminum composite plate is 1.5-5.0 mm, the copper-aluminum composite plate has a non-straight interface, and the interface bonding strength is greater than 90 MPa.

[0019] Furthermore, in step S1, the material of the copper plate is pure copper, and the models include T1, T2, and T3, and the initial thickness is 0.5-2.0 mm.

[0020] Furthermore, in step S3, the models of the aluminum plates include 1060, 3003, and 6061, and the initial thickness is 2.0-6.0 mm.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1. The present invention firstly performs roller processing on the copper plate to form a shuttle-shaped relief on the surface of the copper plate; then performs annealing treatment on the copper plate to eliminate work hardening; then pickles the copper plate to remove the surface oxide layer; then selects a hot-rolled aluminum plate, mechanically grinds its surface, removes the surface oxide layer and obtains a rough surface to be composited; then, the copper plate relief surface and the aluminum plate mechanically grind surface are bonded together, and a single-pass large-reduction cold rolling is performed to achieve mechanical bonding at the copper-aluminum interface; finally, the copper-aluminum composite plate is subjected to diffusion heat treatment to eliminate the interface stress and diffuse the interface elements to achieve metallurgical bonding.

[0023] 2. The present invention utilizes the rolling equipment commonly used for steel plates to roll the copper plate to perform shuttle-shaped embossing, does not require new equipment, has a simple process, and has low requirements on equipment.

[0024] 3. The present invention reduces the required reduction amount for cold rolling composite of copper and aluminum billets through copper layer rolling treatment and surface mechanical grinding process, which can guide the cold rolling composite process design of other metal layered composite materials.

[0025] 4. The copper-aluminum composite plate prepared by the present invention has a non-straight interface, which increases the interface bonding area and improves the interface bonding strength.

[0026] Based on the above reasons, the present invention can be widely promoted in the fields of preparation of metal layered composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 It is a process flow chart of the method of the present invention.

[0029] Figure 2 This is a morphology diagram of the shuttle-shaped relief on the surface of the copper layer after roller pressing according to the present invention. DETAILED DESCRIPTION

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0033] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be clear that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0034] The invention provides a method for preparing a copper-aluminum composite plate, which is used to solve the problem that the existing rolling composite technology is difficult to prepare a copper-aluminum composite plate with high interface bonding quality.

[0035] like Figure 1 As shown, the method for preparing the copper-aluminum composite plate provided by the present invention comprises the following steps:

[0036] S1. Roll the copper plate to create a number of shuttle-shaped reliefs on the surface of the copper plate. The angle between the direction of the shuttle-shaped relief and the width direction of the copper plate is 45°, and the height of the shuttle-shaped relief is 0.2-0.5 mm. The shuttle-shaped reliefs are evenly distributed, and the local structure of one distribution form is as follows: Figure 2As shown, the direction from the lower left corner to the upper right corner and forming an angle of 45° with the width direction of the copper plate is the first oblique direction, and the direction from the upper left corner to the lower right corner and forming an angle of 45° with the width direction of the copper plate is the second oblique direction; multiple rows of shuttle-shaped embossments are arranged at equal intervals along the first oblique direction, and multiple shuttle-shaped embossments are arranged at equal intervals in each row; multiple rows of shuttle-shaped embossments are arranged at equal intervals along the second oblique direction, and multiple shuttle-shaped embossments are arranged at equal intervals in each row;

[0037] S2, alkali washing the copper plate after rolling to remove the rolling oil on the surface; then annealing the copper plate after alkali washing to eliminate work hardening, requiring the hardness of the copper plate after annealing to be less than 100HV, then pickling the annealed copper plate to remove the surface oxide layer to obtain a clean and rough surface to be composited;

[0038] S3. Select a hot-rolled aluminum plate and mechanically grind its surface to remove the surface oxide layer and obtain a rough surface to be composited. The angle between the grinding direction and the width direction of the aluminum plate is required to be 45°, and the surface roughness after grinding is Ra>2μm;

[0039] S4, laminating the embossed surface of the pickled copper plate and the mechanically polished surface of the aluminum plate, and cold rolling with a large reduction in a single pass to achieve mechanical bonding between the copper and aluminum interfaces, with a reduction of 35%-42%;

[0040] S5. Perform diffusion heat treatment on the copper-aluminum composite plate to eliminate interface stress and diffuse interface elements to achieve metallurgical bonding. The heat treatment temperature is 300°C-350°C and the insulation time is 6-8h.

[0041] As a preferred embodiment, the copper plate is made of pure copper, and the model may be but not limited to one of T1, T2 or T3, and the initial thickness is 0.5-2.0 mm. The aluminum plate may be but not limited to one of 1060, 3003 or 6061, and the initial thickness is 2.0-6.0 mm;

[0042] As a preferred embodiment, in step S5, the thickness of the copper-aluminum composite plate is 1.5-5.0 mm, the prepared copper-aluminum composite plate has a non-straight interface, and the interface bonding strength is greater than 90 MPa.

[0043] The method of the invention can manufacture a copper-aluminum composite plate with high interface bonding strength by using traditional equipment, and has the advantages of low production cost, simple process and easy industrial promotion.

[0044] Example 1

[0045] The material of the copper plate is T1 pure copper, and the initial thickness of the copper plate is 2.0mm. The material of the aluminum plate is 1060 pure aluminum, and the initial thickness of the aluminum plate is 6.0mm. First, the copper plate is rolled to form a shuttle-shaped relief on the surface of the copper plate. The angle between the direction of the shuttle-shaped relief and the width direction of the copper plate is 45°, and the height of the shuttle-shaped relief is 0.5mm; then the copper plate is alkali washed, annealed and pickled, and the hardness of the copper plate after annealing is 90HV; then the hot-rolled 1060 aluminum plate is selected, and its surface is mechanically polished, and the angle between the polishing direction and the width direction of the aluminum plate is 45°. The surface roughness of the aluminum plate after polishing is Ra=3.5μm; then the embossed surface of the copper plate and the mechanically polished surface of the aluminum plate are bonded together, and a single pass large reduction cold rolling is performed to achieve mechanical bonding at the copper-aluminum interface, and the reduction is 42%; finally, the copper-aluminum composite plate is subjected to diffusion heat treatment, and the heat treatment temperature is 300℃ and the insulation time is 8h. The interface bonding strength of the copper-aluminum composite plate after diffusion heat treatment is 96MPa.

[0046] Example 2

[0047] The material of the copper plate is T2 pure copper, and the initial thickness of the copper plate is 1.0mm. The material of the aluminum plate is 6061 pure aluminum, and the initial thickness of the aluminum plate is 4.0mm. First, the copper plate is rolled to form a shuttle-shaped relief on the surface of the copper plate. The angle between the direction of the shuttle-shaped relief and the width direction of the copper plate is 45°, and the height of the shuttle-shaped relief is 0.3mm; then the copper plate is alkali washed, annealed and pickled, and the hardness of the copper plate after annealing is 96HV; then the hot-rolled 6061 aluminum plate is selected, and its surface is mechanically polished, and the angle between the polishing direction and the width direction of the aluminum plate is 45°. The surface roughness of the aluminum plate after polishing is Ra=2.7μm; then the embossed surface of the copper plate and the mechanically polished surface of the aluminum plate are bonded together, and a single pass large reduction cold rolling is performed to achieve mechanical bonding at the copper-aluminum interface, and the reduction is 40%; finally, the copper-aluminum composite plate is subjected to diffusion heat treatment, and the heat treatment temperature is 350℃ and the insulation time is 6h. The interface bonding strength of the copper-aluminum composite plate after diffusion heat treatment is 110MPa.

[0048] Example 3

[0049] The material of the copper plate is T1 pure copper, and the initial thickness of the copper plate is 0.5mm. The material of the aluminum plate is 3003 pure aluminum, and the initial thickness of the aluminum plate is 2.0mm. First, the copper plate is rolled to form a shuttle-shaped relief on the surface of the copper plate. The angle between the direction of the shuttle-shaped relief and the width direction of the copper plate is 45°, and the height of the shuttle-shaped relief is 0.2mm; then the copper plate is alkali washed, annealed and pickled, and the hardness of the copper plate after annealing is 92HV; then the hot-rolled 3003 aluminum plate is selected, and its surface is mechanically polished, and the angle between the polishing direction and the width direction of the aluminum plate is 45°. The surface roughness of the aluminum plate after polishing is Ra=3.0μm; then the embossed surface of the copper plate and the mechanically polished surface of the aluminum plate are bonded together, and a single pass large reduction cold rolling is performed to achieve mechanical bonding at the copper-aluminum interface, and the reduction is 36%; finally, the copper-aluminum composite plate is subjected to diffusion heat treatment, and the heat treatment temperature is 350℃ and the insulation time is 6h. The interface bonding strength of the copper-aluminum composite plate after diffusion heat treatment is 102MPa.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a copper-aluminum composite plate, characterized in that: The steps include: S1, rolling the copper plate to form a plurality of reliefs on the surface of the copper plate; S2, sequentially performing alkali washing, annealing and pickling on the copper plate after roller pressing; S3, selecting a hot-rolled aluminum plate and mechanically grinding the surface of the aluminum plate; S4, laminating the embossed surface of the pickled copper plate and the mechanically polished surface of the aluminum plate to form a blank, and performing single-pass cold rolling with a large reduction to achieve mechanical bonding at the copper-aluminum interface to obtain a composite plate; S5. Performing diffusion heat treatment on the composite plate to prepare a copper-aluminum composite plate.

2. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In the step S1, the embossment is in a shuttle shape, the angle between the direction of the shuttle-shaped embossment and the width direction of the copper plate is 45°, and the height of the shuttle-shaped embossment is 0.2-0.5 mm.

3. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In the step S2, the hardness of the copper plate after annealing is less than 100 HV.

4. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In the step S3, the angle between the mechanical grinding direction and the width direction of the aluminum plate is 45°, and the surface roughness Ra of the aluminum plate after grinding is greater than 2 μm.

5. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In step S4, the pressing amount is 35%-42%.

6. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In step S5, the heat treatment temperature is 300° C.-350° C., and the heat preservation time is 6-8 hours.

7. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In the step S5, the thickness of the copper-aluminum composite plate is 1.5-5.0 mm, the copper-aluminum composite plate has a non-straight interface, and the interface bonding strength is greater than 90 MPa.

8. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In the step S1, the material of the copper plate is pure copper, and the types include T1, T2, and T3, and the initial thickness is 0.5-2.0 mm.

9. The method for preparing the copper-aluminum composite plate according to claim 1, characterized in that: In step S3, the types of the aluminum plates include 1060, 3003, and 6061, and the initial thickness is 2.0-6.0 mm.

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