Preparation process of high-strength and high-conductivity copper-aluminum composite material and composite material

Abstract

The invention aims at disclosing a high-strength and high-conductivity copper-aluminum composite material preparation process and a composite material, and relates to the technical field of metal composite materials, the high-strength and high-conductivity copper-aluminum composite material preparation process comprises the following steps that a high-strength copper alloy strip is heated to a first temperature, and the first temperature ranges from 100 DEG C to 150 DEG C; the high-wettability aluminum alloy is liquefied and heated to a second temperature, liquid aluminum alloy is obtained, and the second temperature is 30-60 DEG C higher than the melting point of the high-wettability aluminum alloy; and S3, the liquid aluminum alloy and the high-strength copper alloy strip are subjected to continuous cast rolling, heat of the high-strength copper alloy strip is transferred to a third temperature from the first temperature, and the third temperature is 30-60 DEG C higher than the unit cell transformation temperature of the high-strength copper alloy strip. Si is used for increasing the wettability between aluminum and copper and increasing the stripping force between the copper-aluminum composite material; and by controlling the first temperature, the second temperature and the third temperature, the stripping force between the copper-aluminum composite materials is further increased.

Description

Technical Field

[0001] The present invention relates to the technical field of metal composite materials, and in particular to a preparation process of a high-strength and high-conductivity copper-aluminum composite material and the composite material. Background Art

[0002] In the fields of aerospace, transportation, electronic communications, marine engineering, special equipment, etc., high strength and high conductivity are required for conductor materials, and copper-aluminum composite materials are one of the good choices.

[0003] At present, copper-aluminum composite materials are composites of copper strips and aluminum strips, which have defects such as low peel strength, easy delamination, insufficient tensile strength, and insufficient electrical conductivity.

[0004] In view of this, it is necessary to develop a high-strength and high-conductivity copper-aluminum composite material preparation process and composite material to overcome the above-mentioned defects. Summary of the invention

[0005] The purpose of the invention is to disclose a preparation process of a high-strength and high-conductivity copper-aluminum composite material and the composite material.

[0006] The first object of the present invention is to provide a process for preparing a high-strength and high-conductivity copper-aluminum composite material.

[0007] The second object of the present invention is to provide a high-strength and high-conductivity copper-aluminum composite material.

[0008] To achieve the above first invention objective, the present invention provides a process for preparing a high-strength and high-conductivity copper-aluminum composite material, comprising the following steps:

[0009] Heating the high-strength copper alloy strip to a first temperature, wherein the first temperature is 100° C.-150° C.;

[0010] liquefying the high wettability aluminum alloy and heating it to a second temperature to obtain a liquid aluminum alloy, wherein the second temperature is 30° C. to 60° C. higher than the melting point of the high wettability aluminum alloy;

[0011] Step S3: continuously casting and rolling the liquid aluminum alloy and the high-strength copper alloy strip, wherein the high-strength copper alloy strip is heated from the first temperature to a third temperature, wherein the third temperature is 30° C.-60° C. higher than the unit cell transformation temperature of the high-strength copper alloy strip.

[0012] Preferably, the speed of the continuous casting is 0.5 m / s-3 m / s.

[0013] Preferably, the speed of the continuous casting is 1 m / s-2 m / s.

[0014] Preferably, the rolling force of the continuous casting is 1000t-2000t.

[0015] Preferably, the rolling force of the continuous casting is maintained at 2000t.

[0016] Preferably, the initial thickness of the high-strength copper alloy strip is 4 mm-5 mm, and the initial thickness accounts for 30%-50% of the total initial thickness of the copper-aluminum composite material.

[0017] Preferably, the reduction ratio of the continuous casting is 10%-15%.

[0018] Preferably, the liquid aluminum alloy is transported to the casting and rolling zone via a guide groove and a casting nozzle.

[0019] Preferably, the surface temperature of the casting rolls of the continuous casting is 350° C.-430° C.; and the high-strength copper alloy strip is heated to the first temperature by a copper strip auxiliary heating device.

[0020] Based on the same inventive principle, in order to achieve the above second inventive object, the present invention provides a high-strength and high-conductivity copper-aluminum composite material, which is composed of a high-strength copper alloy layer and a high-wettability aluminum alloy layer, wherein the thickness of the high-strength copper alloy layer accounts for 30%-50% of the total thickness;

[0021] The high-strength and high-conductivity copper-aluminum composite material is processed into a high-strength and high-conductivity copper-aluminum composite material through the high-strength and high-conductivity copper-aluminum composite material preparation process described in the first invention.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The high wettability aluminum alloy of the present invention contains Si. The function of Si is to increase the wettability between aluminum and copper, ensure the wettability between the high wettability aluminum alloy liquid and the high-strength copper alloy strip, and increase the peeling force between the copper-aluminum composite materials. Indispensably, the first temperature is the initial temperature of the high-strength copper alloy strip. When the high wettability aluminum alloy liquid and the high-strength copper alloy strip having the first temperature are continuously cast and rolled, the heat of the high wettability aluminum alloy liquid will be transferred and diffused to the high-strength copper alloy strip, and the temperature of the high-strength copper alloy strip will reach the third temperature. The third temperature is 30°C-60°C higher than the unit cell transformation temperature of the high-strength copper alloy strip. By controlling the first temperature, the second temperature and the third temperature, the peeling force between the copper-aluminum composite materials is further increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a process flow chart for preparing the high-strength and high-conductivity copper-aluminum composite material of the present invention.

[0025] Figure 2 It is a cross-sectional view of the high-strength and high-conductivity copper-aluminum composite material of the present invention.

[0026] Figure 3 It is an electron microscope image of the copper-aluminum casting and rolling interface of the present invention.

[0027] Figure 4It is an element line scan diagram of the copper-aluminum casting and rolling interface of the present invention.

[0028] Among them, 1. High-strength copper alloy layer; 2. High-wettability aluminum alloy layer. DETAILED DESCRIPTION

[0029] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thick", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0031] Embodiment 1

[0032] The present embodiment provides a preparation process of a high-strength and high-conductivity copper-aluminum composite material, comprising the following steps: Step S1: heating the high-strength copper alloy strip to a first temperature, the first temperature being 100°C-150°C; specifically, the material of the high-strength copper alloy strip is preferably T2 copper alloy or C18150 copper alloy, the first temperature is the initial temperature of the high-strength copper alloy strip, and the initial temperature can ensure that the composite temperature with the high-wettability aluminum alloy during subsequent continuous rolling meets the requirements, thereby ensuring the composite strength; the high-strength copper alloy strip is heated to the first temperature by a copper strip auxiliary heating device, that is, the high-strength copper alloy strip is heated to the first temperature after passing through the auxiliary heating device.

[0033] Step S2: liquefying the high wettability aluminum alloy and heating it to a second temperature to obtain a liquid aluminum alloy, wherein the second temperature is 30°C-60°C higher than the melting point of the high wettability aluminum alloy; specifically, the material of the high wettability aluminum alloy is preferably 1060 aluminum alloy or 8011 aluminum alloy, and the function of Si in the high wettability aluminum alloy is to increase the wettability between aluminum and copper, thereby ensuring the wettability between the high wettability aluminum alloy liquid and the high-strength copper alloy strip, and increasing the peeling force between the copper-aluminum composite material; in addition, the second temperature is 30°C-60°C higher than the melting point of the high wettability aluminum alloy, and the second temperature is preferably 35°C higher than the melting point of the high wettability aluminum alloy, so that the high wettability aluminum alloy carries sufficient heat.

[0034] Step S3: Continuously casting and rolling the liquid aluminum alloy and the high-strength copper alloy strip, the high-strength copper alloy strip is heat-transferred from the first temperature to a third temperature, and the third temperature is 30°C-60°C higher than the unit cell transformation temperature of the high-strength copper alloy strip. Specifically, the liquid aluminum alloy is transported to the casting and rolling zone through the guide groove and the casting nozzle. On the basis of ensuring the high wettability between copper and aluminum by using the high-wettability aluminum alloy, in order to further ensure the composite strength between copper and aluminum, the first temperature is the initial temperature of the high-strength copper alloy strip, and the first temperature is preferably 130°C. When the high-wettability aluminum alloy liquid and the high-strength copper alloy strip having the first temperature are continuously cast and rolled, the heat of the high-wettability aluminum alloy liquid will be transferred and diffused to the high-strength copper alloy strip, and the temperature of the high-strength copper alloy strip reaches the third temperature, and the third temperature is 30°C-60°C higher than the unit cell transformation temperature of the high-strength copper alloy strip, the unit cell transformation temperature is preferably 400°C, and the third temperature is preferably 430°C. By controlling the first temperature, the second temperature and the third temperature, the peeling force between the copper-aluminum composite materials is further increased.

[0035] It should be noted that, in this embodiment, the initial thickness of the high-strength copper alloy strip is 4mm-5mm, and the initial thickness accounts for 30%-50% of the total initial thickness of the copper-aluminum composite material. The tensile strength of the copper-aluminum composite material after continuous casting and rolling is >330Mpa, the electrical conductivity is >66%IACS, and the peeling force is >80N / mm.

[0036] In order to ensure the peeling force between the copper-aluminum composite materials, the following three aspects are simultaneously ensured: first, the material of the high wettability aluminum alloy is preferably 1060 aluminum alloy or 8011 aluminum alloy; second, the first temperature, the second temperature and the third temperature are controlled, the surface temperature of the casting roll of the continuous casting is 350℃-430℃, the surface temperature of the casting roll is close to the surface temperature of the composite material, and the temperature of the composite material is prevented from diffusing to the casting roll; third, the rolling force of the continuous casting is 1000t-200 0t, the rolling force of the continuous casting is preferably 2000t, the speed of the continuous casting is 0.5m / s-3m / s, the speed of the continuous casting is preferably 1m / s-2m / s, the pressing rate of the continuous casting is 10%-15%, and the rolling force of 2000t and the pressing rate of 10%-15% further ensure the composite strength between copper and aluminum; the interface electron microscope image between the high-strength copper alloy strip (C18150 copper alloy) and the high wettability aluminum alloy (1060 aluminum alloy), see Figure 3 It can be seen that the interface of the composite material prepared by casting and rolling is flat and well bonded. The SEM morphology of the high-strength copper alloy strip and the high-wettability aluminum alloy composite material shows that there are no obvious holes and impurity defects at the interface, the Cockendall effect produced by diffusion is weak, and an interface layer of about 0.8μm is produced. The interface line on both sides of copper and aluminum is smooth, and the metallurgical state is good, which is conducive to the subsequent rolling processing and heat treatment; see Figure 4 , Figure 4 It is the element line scan display, Figure 3 The atomic ratio of aluminum atoms to copper atoms at point 1 is close to 4:9. Figure 3 The atomic ratio of aluminum atoms to copper atoms at point 2 is close to 2:1. From the copper side to the aluminum side, the copper content gradually decreases while the aluminum content is the opposite. Based on the above analysis, it can be determined that the interface is divided into two layers. The interface layer close to copper is Al. 4 Cu 9 Interface compound, the interface layer close to aluminum is Al 2 Cu interface compounds.

[0037] See Table 1, which is a performance parameter table of copper-aluminum composite materials.

[0038] Table 1 Performance parameters of copper-aluminum composite materials

[0039]

[0040]

[0041] From the test results in Table 1, it can be seen that the influence on the peel strength N / mm (peeling copper), tensile strength MPa, conductivity and other aspects of the copper-aluminum composite material is mainly reflected in the following aspects: (1) The first temperature is the key factor. The second temperature and the first temperature combine to ensure the third temperature, thereby ensuring the composite strength and tensile strength; (2) The rolling force plays an auxiliary role in the peel strength N / mm (peeling copper) and tensile strength MPa; (3) The selection of copper alloy and aluminum alloy models provides a basic guarantee for the peel strength N / mm (peeling copper), tensile strength MPa, conductivity and other aspects.

[0042] Embodiment 2

[0043] See also Figure 2 A high-strength and high-conductivity copper-aluminum composite material, consisting of a high-strength copper alloy layer 1 and a high-wettability aluminum alloy layer 2, wherein the thickness of the high-strength copper alloy layer 1 accounts for 30%-50% of the total thickness; the high-strength and high-conductivity copper-aluminum composite material is processed into the high-strength and high-conductivity copper-aluminum composite material by the high-strength and high-conductivity copper-aluminum composite material preparation process described in Example 1. Specifically, the high-strength copper alloy strip is continuously cast and rolled to form the high-strength copper alloy layer 1, and the high-wettability aluminum alloy is continuously cast and rolled to form the high-wettability aluminum alloy layer 2. The copper-aluminum composite material after continuous casting and rolling has a tensile strength of >330Mpa, a conductivity of >66%IACS, and a peeling force of >80N / mm, meeting the requirements of high strength and high conductivity.

[0044] For the parts of the high-strength and high-conductivity copper-aluminum composite material described in Example 2 that are the same as those in Example 1, please refer to Example 1 and will not be described in detail here.

Claims

1. A process for preparing a high-strength and high-conductivity copper-aluminum composite material, characterized in that: The following steps are involved: Heating the high-strength copper alloy strip to a first temperature, wherein the first temperature is 100° C.-150° C.; liquefying the high wettability aluminum alloy and heating it to a second temperature to obtain a liquid aluminum alloy, wherein the second temperature is 30° C. to 60° C. higher than the melting point of the high wettability aluminum alloy; The liquid aluminum alloy and the high-strength copper alloy strip are continuously cast and rolled, and the high-strength copper alloy strip is heated from the first temperature to a third temperature, and the third temperature is 30° C.-60° C. higher than the unit cell transformation temperature of the high-strength copper alloy strip.

2. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 1, characterized in that: The speed of the continuous casting is 0.5m / s-3m / s.

3. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 2, characterized in that: The speed of the continuous casting is 1m / s-2m / s.

4. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 1, characterized in that: The rolling force of the continuous casting and rolling is 1000t-2000t.

5. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 4, characterized in that: The rolling force of the continuous casting and rolling is maintained at 2000t.

6. The process for preparing a high-strength and high-conductivity copper-aluminum composite material according to any one of claims 1 to 5, characterized in that: The initial thickness of the high-strength copper alloy strip is 4 mm to 5 mm, and the initial thickness accounts for 30% to 50% of the total initial thickness of the copper-aluminum composite material.

7. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 6, characterized in that: The continuous casting and rolling has a reduction ratio of 10% to 15%.

8. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 6, characterized in that: The liquid aluminum alloy is transported to the casting and rolling area through the guide groove and the casting nozzle.

9. The process for preparing the high-strength and high-conductivity copper-aluminum composite material according to claim 6, characterized in that: The surface temperature of the casting rolls of the continuous casting is 350°C-430°C; The high-strength copper alloy strip is heated to a first temperature by a copper strip auxiliary heating device.

10. High-strength and high-conductivity copper-aluminum composite material, characterized in that: It consists of a high-strength copper alloy layer and a high-wettability aluminum alloy layer, wherein the thickness of the high-strength copper alloy layer accounts for 30%-50% of the total thickness; The high-strength and high-conductivity copper-aluminum composite material is processed into a high-strength and high-conductivity copper-aluminum composite material through the high-strength and high-conductivity copper-aluminum composite material preparation process described in any one of claims 1-9.

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