High-elastic copper alloy foil and preparation method thereof

Abstract

The invention discloses a high-elastic copper alloy foil and a preparation method thereof. The preparation method comprises the following steps that 1, an inner-layer alloy material and an outer-layer alloy material are manufactured; 2, the inner-layer alloy material and the outer-layer alloy material are cleaned; 3, preheating the inner-layer alloy material and the outer-layer alloy material; 4, the preheated inner-layer alloy material and the preheated outer-layer alloy material are extruded through an extrusion die; 5, the copper alloy foil strip is cut into the needed size through a cutting machine; and 6, the copper alloy foil belt is subjected to surface treatment, and preparation is completed. The high-elasticity copper alloy foil is prepared through the steps. A double-layer composite structure is adopted for preparation, the corrosion resistance of the alloy is effectively enhanced, reinforcing phases such as aluminum oxide whiskers and silicon carbide particles are introduced into copper alloy melt, the strength and hardness of the material are further improved, and meanwhile good elasticity is kept.

Description

Technical Field

[0001] The invention relates to the technical field of copper alloy preparation, and in particular to a high-elastic copper alloy foil and a preparation method thereof. Background Art

[0002] As an important engineering material, copper alloy is widely used in electronics, communications, automobiles, construction and other fields due to its good conductivity, corrosion resistance and processing performance. However, with the continuous upgrading of industrial technology and application requirements, especially in high elasticity, high strength and high temperature environments, conventional copper alloy materials can no longer meet the stringent performance requirements. In particular, in engineering fields that require materials to have higher elasticity, the elastic modulus of traditional copper alloy foils often cannot meet the requirements, which limits its promotion and use in high elasticity application scenarios.

[0003] In modern engineering applications, especially in the electronics industry, the elasticity of copper alloy foil plays a vital role in the performance of devices. Traditional copper alloy foil is generally strengthened by simple composition adjustment or heat treatment. However, while improving the strength and ductility of the alloy, its elasticity and plasticity are often sacrificed. Therefore, how to improve the comprehensive performance of copper alloy foil while ensuring its high elasticity is an urgent problem to be solved. Summary of the invention

[0004] The purpose of the present invention is to solve the defects in the prior art and to propose a high elastic copper alloy foil and a preparation method thereof.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preparing a high elastic copper alloy foil comprises the following steps:

[0007] Step 1: Select Cu, Ni, and Al as the main preparation materials, and make inner layer alloy materials and outer layer alloy materials respectively through smelting, solidification, and molding;

[0008] Step 2: Clean the inner alloy material and the outer alloy material, then mechanically grind or sandblast the inner alloy material, and pickle the outer alloy material;

[0009] Step 3: Preheat the inner and outer alloy materials to the target temperature and keep them for 30 to 60 minutes;

[0010] Step 4: The preheated inner and outer alloy materials are extruded through an extrusion die respectively, and then composited, and then the outer alloy material is wrapped around the inner alloy material, and preheated and extruded again to form a composite strip, wherein the extrusion pressure is controlled at 100-200 MPa, and the extrusion speed can be controlled at 0.5-2 m / s according to the material thickness;

[0011] Step 5: hot rolling the extruded composite strip at 300°C to 900°C to form a preset shape, followed by water cooling and annealing, and cutting the copper alloy foil strip into required sizes using a cutting machine;

[0012] Step 6: Surface treatment of the copper alloy foil strip is performed to complete the preparation.

[0013] Further, the inner layer alloy material is an alloy strip with a thickness between 0.1 mm and 2 mm;

[0014] The outer alloy material is an alloy strip with a thickness between 0.05 and 0.5 mm;

[0015] The thickness of the inner layer alloy material accounts for 70%-90%, and the thickness of the outer layer alloy material accounts for 15%-30%.

[0016] Furthermore, the inner layer alloy material includes the following raw materials in percentage by mass:

[0017] Cu: 85%-95%, Ni: 1%-3%, Al: 2%-5%, Mn: 7%-12%, Si: 0.5%-1%.

[0018] Furthermore, the outer layer alloy material includes the following raw materials by mass percentage: Al: 90%-95%, Mg: 4%-6% (to improve strength and corrosion resistance), Si: 1%-3% (to improve the strength of aluminum alloy), Cu: 0.5%-1% (to improve the strength and wear resistance of the alloy)

[0019] Further, in step 3, the inner layer alloy material is heated to 300°C-400°C, and the outer layer alloy material is heated to 350°C-450°C at a heating rate of 5°C / min-10°C / min.

[0020] Furthermore, the composite processing steps in step 4 are:

[0021] 3-Aminopropyltriethoxysilane (APTES) was selected as a coupling agent for plasma treatment, with a concentration in the range of 0.5%-1%, and a coating amount of 1-2 g / m2 on the inner copper alloy surface. 2 ;

[0022] Plasma treatment conditions:

[0023] Power: 100-300W; Processing time: 2-5 minutes; Gas type: oxygen or nitrogen.

[0024] Furthermore, when preparing the inner alloy material, 2wt% alumina whiskers and 3wt% silicon carbide particles were simultaneously added to the copper alloy melt and evenly dispersed into the copper alloy melt by a stirrer at a stirring rate of 4000rpm and a processing time of 10 minutes.

[0025] Furthermore, the diameter of the aluminum oxide whisker is 0.5 μm and the length is 10 μm;

[0026] The surface of aluminum oxide whiskers is coated with aminosilane coupling agent with a concentration of 1% and a coating amount of 1g / m 2 , the processing time is 5 minutes;

[0027] The content of aluminum oxide whiskers in the copper alloy is 2wt%;

[0028] Silicon carbide particles, with a particle size of 1 μm, are surface coated by chemical plating, with a coating amount of 0.5 g / m 2 During the stirring process, ultrasonic vibration is used to disperse the silicon carbide particles. The ultrasonic power is 200 W, the frequency is 40 kHz, and the processing time is 5 minutes.

[0029] Furthermore, in step 1, the molten copper alloy is poured into a preheated directional solidification mold to solidify the alloy along a specific direction, wherein the solidification rate of the alloy is controlled by adjusting the cooling system, and the solidification rate is maintained between 0.5-2°C / min to orient the growth direction of the grains during the solidification process.

[0030] According to another aspect of the present invention, a high elastic copper alloy foil is provided.

[0031] A high elastic copper alloy foil is prepared according to the above method.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] By adding appropriate amounts of nickel, aluminum, manganese and other elements to the inner layer alloy material, the grain structure of the alloy is optimized, so that the copper alloy foil has higher tensile strength and elastic modulus while maintaining good plasticity; the double-layer composite structure is adopted, and the corrosion resistance of the alloy is effectively enhanced through the reasonable ratio of the outer layer alloy material (such as high aluminum content), especially in a humid environment, it exhibits a longer corrosion resistance. In addition, plasma treatment and silane coupling agent treatment are used to improve the adhesion between the composite layers and ensure the structural stability of the material. It can be widely used in electronic devices, automotive electrical systems, aerospace and high temperature and high pressure environments. The prepared alloy foil also has good processing performance and is suitable for large-scale production. By introducing reinforcing phases such as aluminum oxide whiskers and silicon carbide particles into the copper alloy melt, the strength and hardness of the material are further improved while maintaining good elasticity. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0035] Figure 1 Schematic diagram of the process of preparing a high elastic copper alloy foil in an embodiment of the present invention. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be described clearly and completely 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, rather than all the embodiments.

[0037] like Figure 1 As shown, a method for preparing a high elastic copper alloy foil comprises the following steps:

[0038] Step 1: Select Cu, Ni, and Al as the main preparation materials, and make inner layer alloy materials and outer layer alloy materials respectively through smelting, solidification, and molding, wherein the inner layer alloy material uses copper as the main alloy, and the outer layer alloy material uses aluminum and nickel as the main alloy;

[0039] Step 2: Clean the inner alloy material and the outer alloy material, then mechanically grind or sandblast the inner alloy material, and pickle the outer alloy material;

[0040] Step 3: preheat the inner and outer alloy materials, using a heating rate of 5°C / min-10°C / min, heating the inner alloy material to 300°C-400°C, and the outer alloy material to 350°C-450°C, and the holding time after heating to the target temperature is 30 minutes to 60 minutes;

[0041] It should be noted that the inner alloy material is heated to 300℃-400℃ and the outer alloy material is heated to 350℃-450℃ at a heating rate of 5℃ / min-10℃ / min. Controlling the heating rate to 5℃ / min-10℃ / min can avoid thermal stress caused by excessive temperature difference between the inner and outer layers and reduce the risk of separation between materials.

[0042] Step 4: The preheated inner and outer alloy materials are extruded through an extrusion die respectively, and then composited, and then the outer alloy material is wrapped around the inner alloy material, and preheated and extruded again to form a composite strip, wherein the extrusion pressure is controlled at 100-200 MPa, and the extrusion speed can be controlled at 0.5-2 m / s according to the material thickness;

[0043] Step 5: hot rolling the extruded composite strip at 300°C to 900°C to form a preset shape, followed by water cooling and annealing, and cutting the copper alloy foil strip into required sizes using a cutting machine;

[0044] Step 6: Surface treatment of the copper alloy foil strip is performed to complete the preparation.

[0045] In a specific embodiment of the present application, the inner layer alloy material is an alloy strip with a thickness between 0.1 mm and 2 mm;

[0046] The outer alloy material is an alloy strip with a thickness between 0.05 and 0.5 mm;

[0047] The thickness of the inner layer alloy material accounts for 70%-90%, and the thickness of the outer layer alloy material accounts for 15%-30%.

[0048] In a preferred embodiment of the present application, the inner layer alloy material includes the following raw materials in percentage by mass:

[0049] Cu: 85%-95%, Ni: 1%-3% (increases oxidation resistance and corrosion resistance), Al: 2%-5% (increases strength and heat resistance of the alloy), Mn: 7%-12% (improves strength and wear resistance), Si: 0.5%-1% (improves fluidity and corrosion resistance);

[0050] In a preferred embodiment of the present application, the manganese content is 10%-12%: it is suitable for improving the strength and hardness of the alloy while maintaining good plasticity and ductility, and can stably form a face-centered cubic (FCC) lattice structure, so that the elasticity of the alloy is optimized, and it is suitable for engineering materials requiring higher elasticity.

[0051] The outer alloy material includes the following percentages by mass: Al: 90%-95%, Mg: 4%-6% (to improve strength and corrosion resistance), Si: 1%-3% (to improve the strength of aluminum alloy), Cu: 0.5%-1% (to improve the strength and wear resistance of the alloy)

[0052] In a preferred embodiment of the present application, the composite processing steps in step 4 are:

[0053] 3-Aminopropyltriethoxysilane (APTES) was selected as a coupling agent for plasma treatment, with a concentration in the range of 0.5%-1%, and a coating amount of 1-2 g / m2 on the inner copper alloy surface. 2 .

[0054] Plasma treatment conditions:

[0055] Power: 100-300W; Processing time: 2-5 minutes; Gas type: Oxygen or nitrogen (mainly used for cleaning and activating surfaces)

[0056] It should be noted that silane coupling agents can form a thin film on the surface of copper alloys, enhance the chemical bonding between the surface and the outer layer material, and improve the interfacial adhesion. By reacting with the -OH groups on the surface of the copper alloy, chemical bonds are formed, thereby improving the bonding between the inner and outer layer materials. Plasma treatment can remove the oxide layer, oil stains and other pollutants on the surface of the copper alloy, and generate active oxygen groups through oxidation reactions, thereby further improving the surface roughness and chemical activity and improving interfacial adhesion.

[0057] In another preferred embodiment of the present application, when preparing the inner layer alloy material, 2wt% aluminum oxide whiskers and 3wt% silicon carbide particles are simultaneously added to the copper alloy melt and uniformly dispersed into the copper alloy melt by a stirrer, the stirring rate is 4000rpm, and the processing time is 10 minutes;

[0058] The diameter of the aluminum oxide whiskers is 0.5 μm and the length is 10 μm;

[0059] The surface of the aluminum oxide whisker is coated with an aminosilane coupling agent (such as APTES) at a concentration of 1% and a coating amount of 1 g / m 2 , the processing time is 5 minutes;

[0060] The content of aluminum oxide whiskers in the copper alloy is 2wt%;

[0061] Silicon carbide particles, with a particle size of 1 μm, are surface coated by chemical plating, with a coating amount of 0.5 g / m 2 During the stirring process, ultrasonic vibration is used to disperse the silicon carbide particles. The ultrasonic power is 200 W, the frequency is 40 kHz, and the processing time is 5 minutes.

[0062] In a specific embodiment of the present application, in step 1, the molten copper alloy is poured into a preheated directional solidification mold to solidify the alloy along a specific direction, wherein the solidification rate of the alloy is controlled by adjusting the cooling system (such as a water cooling or air cooling system), and the solidification rate is maintained between 0.5-2°C / min, which is used to orient the growth direction of the grains during the solidification process.

[0063] The present invention also discloses another specific embodiment, a high elastic copper alloy foil, which is prepared according to the steps of the above embodiment.

[0064] Example 1

[0065] The inner alloy is Cu-3Ni-2Al-7Mn-0.5Si, and the outer alloy is aluminum alloy (Al: 90%-95%, Mg: 4%-6%, Si: 1%-3%);

[0066] The molten metal was poured into a mold preheated to 200°C and directional solidification was performed using a cooling rate of 1°C / min;

[0067] The inner and outer alloy materials were cleaned and preheated, then mechanically polished and pickled;

[0068] Subsequently, the heating was carried out at a temperature of 300°C to 400°C at a rate of 5°C / min, and the temperature was maintained for 30 minutes before extrusion. The extrusion pressure was controlled at 150MPa, the speed was 1.5m / s, the thickness of the formed composite strip was 75% for the inner layer and 25% for the outer layer, the hot rolling temperature was 700°C, the annealing temperature was 400°C, and the annealing time was 60 minutes;

[0069] Finally, a highly elastic copper alloy foil strip is obtained.

[0070] Example 2

[0071] Cu-3Ni-2Al-12Mn-0.5Si is used as the inner alloy, and the outer alloy is made of pure nickel. The preparation process described in Example 1 is adopted, but the manganese content in the inner alloy is adjusted to 12% to improve the strength and hardness of the alloy. The copper alloy foil strip finally obtained has higher strength and elasticity after heat treatment and surface coating treatment, and is suitable for high stress and high temperature resistant working environment.

[0072] In order to better understand the technical solution of the present application, further explanation is given below in conjunction with experiments.

[0073] Subjects:

[0074] Example: A copper alloy foil strip prepared according to the steps described in Example 1;

[0075] Comparative Example 1: Any common copper alloy foil strip (Cu≥95%);

[0076] Comparative Example 2: Low manganese copper alloy foil strip (Cu≥85%, Mn≥8%);

[0077] Among them, Comparative Example 1 and Comparative Example 2 were prepared using the same basic process flow, and the following steps were performed respectively:

[0078] The alloy material is melted in an electric arc furnace, and after solidification and cooling, the alloy is cleaned to remove surface oxides and impurities;

[0079] The alloy is preheated, hot rolled, annealed and surface treated in sequence, and cut into size to obtain alloy strips.

[0080] The performance tests were performed on the alloy strips of Example, Comparative Example 1 and Comparative Example 2. The specific results are shown in Table 1.

[0081]

[0082]

[0083] Table 1

[0084] From the above, it can be seen that the elastic modulus of the copper alloy foil prepared in this scheme is 190 GPa. By optimizing the manganese content, the grain structure of the alloy is made more stable, thereby improving the elastic modulus of the alloy;

[0085] In addition, the corrosion depth of this solution is 0.1 mm, and the corrosion resistance is effectively improved through double-layer composite preparation, especially in humid environments, which can provide longer protection.

[0086] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a high elastic copper alloy foil, comprising the following steps: Step 1: Select Cu, Ni, and Al as the main preparation materials, and make inner layer alloy materials and outer layer alloy materials respectively through smelting, solidification, and molding; Step 2: Clean the inner alloy material and the outer alloy material, then mechanically grind or sandblast the inner alloy material, and pickle the outer alloy material; Step 3: Preheat the inner and outer alloy materials to the target temperature and keep them for 30 to 60 minutes; Step 4: The preheated inner and outer alloy materials are extruded through an extrusion die respectively, and then composited, and then the outer alloy material is wrapped around the inner alloy material, and preheated and extruded again to form a composite strip, wherein the extrusion pressure is controlled at 100-200 MPa, and the extrusion speed can be controlled at 0.5-2 m / s according to the material thickness; Step 5: hot rolling the extruded composite strip at 300°C to 900°C to form a preset shape, followed by water cooling and annealing, and cutting the copper alloy foil strip into required sizes using a cutting machine; Step 6: Surface treatment of the copper alloy foil strip is performed to complete the preparation.

2. The method for preparing a high elastic copper alloy foil according to claim 1, characterized in that: The inner alloy material is an alloy strip with a thickness ranging from 0.1 mm to 2 mm; The outer alloy material is an alloy strip with a thickness between 0.05 and 0.5 mm; The thickness of the inner layer alloy material accounts for 70%-90%, and the thickness of the outer layer alloy material accounts for 15%-30%.

3. The method for preparing a high elastic copper alloy foil according to claim 2, characterized in that: The inner alloy material includes the following raw materials by mass percentage: Cu: 85%-95%, Ni: 1%-3%, Al: 2%-5%, Mn: 7%-12%, Si: 0.5%-1%.

4. The method for preparing the high elastic copper alloy foil according to claim 3, characterized in that: The outer layer alloy material includes the following raw materials in percentage by mass: Al: 90%-95%, Mg: 4%-6%, Si: 1%-3%, Cu: 0.5%-1%.

5. The method for preparing a high elastic copper alloy foil according to claim 4, characterized in that: In step 3, the inner layer alloy material is heated to 300°C-400°C, and the outer layer alloy material is heated to 350°C-450°C at a heating rate of 5°C / min-10°C / min.

6. The method for preparing a high elastic copper alloy foil according to claim 5, characterized in that: The compound processing steps in step 4 are: 3-Aminopropyltriethoxysilane was selected as a coupling agent for plasma treatment, with a concentration in the range of 0.5%-1%, and a coating amount of 1-2 g / m2 on the inner copper alloy surface. 2 ; Plasma treatment conditions: Power: 100-300W; Processing time: 2-5 minutes; Gas type: oxygen or nitrogen.

7. The method for preparing a high elastic copper alloy foil according to claim 6, characterized in that: When preparing the inner layer alloy material, 2wt% alumina whiskers and 3wt% silicon carbide particles were added to the copper alloy melt at the same time and evenly dispersed into the copper alloy melt by a stirrer. The stirring rate was 4000rpm and the processing time was 10 minutes.

8. The method for preparing a high elastic copper alloy foil according to claim 7, characterized in that: The diameter of the aluminum oxide whiskers is 0.5 μm and the length is 10 μm; The surface of aluminum oxide whiskers is coated with aminosilane coupling agent with a concentration of 1% and a coating amount of 1g / m 2 , the processing time is 5 minutes; The content of aluminum oxide whiskers in the copper alloy is 2wt%; Silicon carbide particles, with a particle size of 1 μm, are surface coated by chemical plating, with a coating amount of 0.5 g / m 2 During the stirring process, ultrasonic vibration is used to disperse the silicon carbide particles. The ultrasonic power is 200 W, the frequency is 40 kHz, and the processing time is 5 minutes.

9. The method for preparing a high elastic copper alloy foil according to claim 8, characterized in that: In step 1, the molten copper alloy is poured into a preheated directional solidification mold to solidify the alloy along a specific direction, wherein the solidification rate of the alloy is controlled by adjusting the cooling system, and the solidification rate is maintained between 0.5-2°C / min to orient the growth direction of the grains during the solidification process.

10. A high elastic copper alloy foil, characterized in that: Prepared according to the method of claim 1.

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