High-strength CuNiSi alloy rolled copper foil for communication connector and preparation method of high-strength CuNiSi alloy rolled copper foil

Abstract

The invention discloses a high-strength CuNiSi alloy rolled copper foil for a communication connector and a preparation method of the high-strength CuNiSi alloy rolled copper foil, and belongs to the technical field of communication material preparation. The CuNiSi alloy base material is subjected to finish rolling for 2-3 passes, and the total pass power is 45-60%; cleaning and removing oil, and packaging with a soft copper foil; keeping the temperature at 600-800 DEG C for 4-6 hours; rolling is conducted for 2-6 passes, and the total machining rate is 40-85%; cleaning and removing oil; and carrying out surface treatment on the cleaned foil. The CuNiSi foil prepared through the preparation method of the high-strength CuNiSi alloy rolled copper foil for the communication connector breaks through the thickness limit of a copper alloy rolled copper foil, the strength of the copper alloy foil is improved, and meanwhile good conductivity is kept. The high-strength CuNiSi alloy rolled copper foil for the communication connector has the advantages of being thin in thickness, high in strength and good in conductivity, the development process of the copper alloy rolled copper foil is promoted, and the problem of neck clamping in the key technology is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of communication material preparation, and particularly relates to a high-strength CuNiSi alloy rolled copper foil for communication connectors and a preparation method thereof. Background Art

[0002] With the thinning of communication devices such as smart phones and the increase in the capacity of servers, various connectors inside the devices are further miniaturized, narrow-pitched, and the power throughput is increased, and the requirement for thinner foils of materials is also getting higher and higher. At the same time, in order to ensure the connection reliability of the connector contacts, the material is required to have high strength and good bending processability. Especially in the application of substrates, in addition to miniaturization, the problem of heat generation must also be solved in the substrate connectors. Among all metals, the electrical and thermal conductivity of copper is second only to silver, and the electrical conductivity of pure copper is the best at 102% IACS. Steel is a very common high-strength material at present, but its electrical conductivity is poor. The traditional "copper / stainless steel / copper" three-layer composite material can no longer meet the requirements, and it is necessary to develop copper alloy foils with higher strength, better electrical conductivity, and thinner thickness.

[0003] Domestic enterprises started relatively late in the research, development and production of high-end and high-performance copper alloys, and there is a lack of technical precipitation. Although some enterprises have the ability to produce copper alloy strip foils, the products are mostly concentrated in mid- to low-end applications. Especially in the preparation technology of CuNiSi strip foils, the product thickness is concentrated above 0.1 mm, and it is urgent to develop a preparation technology for copper alloy foils for high-end small connectors with a thickness below 0.1 mm, especially a thickness of 0.04 mm. Summary of the Invention

[0004] Aiming at the problems of high thickness, low strength and poor electrical conductivity of CuNiSi strip foils in the prior art, the present invention provides a high-strength CuNiSi alloy rolled copper foil for communication connectors, a preparation method thereof and an application. The CuNiSi strip foil prepared by the method of the present invention has the characteristics of thin thickness, high strength and good electrical conductivity, promotes the development process of copper alloy rolled copper foils, and solves the key technical problems.

[0005] The present invention is realized through the following technical solutions: A preparation method of a high-strength CuNiSi alloy rolled copper foil for communication connectors, comprising the following steps: (1) Precision rolling: The CuNiSi alloy base material is precision rolled for 2 to 3 passes, and the total pass plus power is 45 to 60%; (2) Cleaning: Cleaning and degreasing, and packaging with soft copper foil; (3) Annealing: Heat preservation at 600 to 800 °C for 4 to 6 h; (4) Finish rolling: Rolling for 2 to 6 passes, and the total processing rate is 40 to 85%; (5) Secondary cleaning: degreasing cleaning; (6) Surface treatment: perform surface treatment on the foil material after cleaning in step (4).

[0006] Further, the CuNiSi alloy base material in step (1) is composed of components with the following weight percentages: Ni 2 - 3%, Si 0.4 - 0.8%, Mg 0.05 - 0.3%, and the balance is Cu.

[0007] Further, the thickness of the CuNiSi alloy base material is 0.1 - 0.4 mm, the tensile strength ≥ 400 MPa, the elongation rate ≥ 10%, the hardness ≥ 120 HV, and the conductivity ≥ 50% IACS.

[0008] Further, the precision rolling conditions in step (1) are: rolling force 600 - 1100 KN, rolling speed 200 - 500 m / min, and tension 5 - 9.5 KN.

[0009] Further, the heating rate during annealing in step (3) is 60 - 100 °C / h.

[0010] Further, the conditions for finish rolling in step (4) are: rolling force 500 - 900 KN, rolling speed 300 - 600 m / min, and tension 2 - 7.5 KN.

[0011] Further, the cleaning speed in steps (2) and (5) is 50 - 100 m / min, and the solution temperature is 20 - 40 °C.

[0012] Further, the surface treatment in step (6) includes electrolytic degreasing, pickling, roughening, curing, anti-oxidation, and passivation.

[0013] Further, the conditions for electrolytic degreasing are: temperature 40 - 60 °C, sodium hydroxide 30 - 50 g / L, sodium carbonate 15 - 30 g / L, current density 4 - 12 A / dm²; the conditions for pickling are: sulfuric acid concentration 100 - 250 g / L; the conditions for roughening are: sulfuric acid concentration 100 - 300 g / L, copper ion concentration 10 - 20 g / L, plating solution temperature 15 - 30 °C, current density 25 - 55 A / dm²; the conditions for curing are: sulfuric acid concentration 80 - 200 g / L, copper ion concentration 40 - 70 g / L, plating solution temperature 30 - 60 °C, current density 10 - 30 A / dm²; the conditions for anti-oxidation are: temperature 25 - 35 °C, zinc ion concentration 1 - 10 g / L, nickel ion concentration 1 - 10 g / L, pH value 9 - 13, current density 2 - 15 A / dm²; the conditions for passivation are: passivation temperature 15 - 30 °C, chromium ion concentration 1 - 10 g / L, pH value 8 - 12, current density 3 - 8 A / dm².

[0014] In the present invention, a high-strength CuNiSi alloy rolled copper foil for communication connectors prepared by the described preparation method.

[0015] Beneficial effects The CuNiSi foil prepared by the preparation method of the high-strength CuNiSi alloy rolled copper foil for communication connectors in the present invention breaks through the thickness limit of copper alloy rolled copper foil, improves the strength of the copper alloy foil while maintaining good electrical conductivity. The high-strength CuNiSi alloy rolled copper foil for communication connectors has the characteristics of thin thickness, high strength and good electrical conductivity, promotes the development process of copper alloy rolled copper foil, and solves key technical problems. Specific embodiments

[0016] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below. Based on the embodiments in this application, other similar embodiments obtained by those of ordinary skill in the art without creative efforts shall all fall within the scope of protection of this application.

[0017] The CuNiSi alloy base material in the following examples is composed of the following components by weight percentage: Ni 2.5%, Si 0.5%, Mg 0.1%, and the balance is Cu; the tensile strength is 500 MPa, the elongation is 16%, the hardness is 150 HV, and the conductivity is 62% IACS. The thickness specification of the base material is 0.15×600 mm.

[0018] Example 1 (1) Precision rolling: The CuNiSi alloy base material is precision rolled for 2 passes to a thickness of 0.07 m, the rolling force is 700 KN, the rolling speed is 200 m / min, and the tension is 5 KN; (2) Cleaning: Clean in a degreasing machine at a cleaning speed of 100 m / min to remove residual rolling oil, and the coiled material is packaged with soft copper foil to protect the coil from being polluted by the external environment; (3) Annealing: Transfer to a bell-type annealing furnace for annealing, hold at 700 °C for 6 h, and the heating rate is 70 °C / h; (4) Final rolling: Transfer to a foil rolling mill and roll repeatedly for 4 passes to a thickness of 0.035 mm, the rolling force is 500 KN, the rolling speed is 300 m / min, and the tension is 3 KN; (5) Secondary cleaning: Clean in a degreasing machine at a cleaning speed of 60 m / min to remove residual rolling oil; (6) Surface treatment: The foils after cleaning in step (4) are subjected to surface treatment to obtain high-strength CuNiSi alloy rolled copper foils for communication connectors; the surface treatment includes electrolytic degreasing, pickling, roughening, curing, anti-oxidation, and passivation; the conditions for electrolytic degreasing are: temperature 40°C, sodium hydroxide 30 g / L, sodium carbonate 15 g / L, current density 6 A / dm²; the pickling conditions are: sulfuric acid concentration 150 g / L; the roughening sulfuric acid concentration is 150 g / L, copper ion concentration is 15 g / L, plating solution temperature is 20°C, and current density is 30 A / dm²; the curing conditions are sulfuric acid concentration 100 g / L, copper ion concentration 50 g / L, plating solution temperature 40°C, and current density 20 A / dm²; the anti-oxidation conditions are: temperature 25°C, zinc ion concentration 5 g / L, nickel ion concentration 5 g / L, pH value 9, and current density 5 A / dm²; the passivation conditions are: passivation temperature 15°C, chromium ion concentration 5 g / L, pH value 9, and current density 4 A / dm².

[0019] Example 2 Compared with Example 1, Example 2 uses a copper foil base material with higher basic strength to ensure the universality of this preparation process; The CuNiSi alloy base material in the following examples has the following composition in weight percentage: Ni 2.5%, Si 0.5%, Mg 0.1%, and the balance is Cu; the tensile strength is 580 MPa, the elongation is 13%, the hardness is 171 HV, and the conductivity is 52% IACS. The base material thickness specification is 0.20×600 mm.

[0020] (1) Precision rolling: The CuNiSi alloy base material is precision rolled 4 passes to a thickness of 0.07 m, the rolling force is 600 KN, the rolling speed is 400 m / min, and the tension is 8 KN; (2) Cleaning: Cleaning is carried out in a degreaser at a cleaning speed of 100 m / min to remove the residual rolling oil, and the coiled material is packaged with soft copper foil to protect the coil from being polluted by the external environment; (3) Annealing: Transfer to a bell-type annealing furnace for annealing, hold at 700°C for 6 h, and the heating rate is 70°C / h; (4) Final rolling: Transfer to a foil rolling mill and roll repeatedly 4 passes to a thickness of 0.035 mm, the rolling force is 500 - 900 KN, the rolling speed is 400 m / min, and the tension is 5 KN; (5) Secondary cleaning: Cleaning is carried out in a degreaser at a cleaning speed of 60 m / min to remove the residual rolling oil; (6) Surface treatment: The foils after cleaning in step (4) are subjected to surface treatment to obtain high-strength CuNiSi alloy rolled copper foils for communication connectors; the surface treatment includes electrolytic degreasing, pickling, roughening, curing, anti-oxidation, and passivation; the conditions for electrolytic degreasing are: temperature 50°C, sodium hydroxide 40 g / L, sodium carbonate 15 g / L, current density 6 A / dm²; the pickling conditions are: sulfuric acid concentration 150 g / L; the roughening conditions are sulfuric acid concentration 150 g / L, copper ion concentration 15 g / L, plating solution temperature 20°C, current density 30 A / dm²; the curing conditions are sulfuric acid concentration 100 g / L, copper ion concentration 50 g / L, plating solution temperature 40°C, current density 20 A / dm²; the anti-oxidation conditions are: temperature 25°C, zinc ion concentration 5 g / L, nickel ion concentration 5 g / L, pH value 9, current density 5 A / dm²; the passivation conditions are: passivation temperature 15°C, chromium ion concentration 5 g / L, pH value 9, current density 4 A / dm².

[0021] Example 3 The composition of the CuNiSi alloy base material in Example 3 has the following weight percentages: Ni 2.5%, Si 0.5%, Mg 0.1%, and the balance is Cu; the tensile strength is 500 MPa, the elongation is 16%, the hardness is 160 HV, and the conductivity is 62% IACS. The thickness specification of the base material is 0.20×600 mm.

[0022] (1) Precision rolling: The CuNiSi alloy base material is precision rolled for 4 passes to a thickness of 0.07 m, the rolling force is 600 KN, the rolling speed is 300 m / min, and the tension is 8 KN; (2) Cleaning: Cleaning is carried out in a degreaser at a cleaning speed of 100 m / min to remove the residual rolling oil, and the coiled material is packaged with soft copper foil to protect the coil from being polluted by the external environment; (3) Annealing: Transfer to a bell-type annealing furnace for annealing, hold at 600°C for 6 h, and the heating rate is 100°C / h; (4) Final rolling: Transfer to a foil rolling mill and repeatedly roll for 4 passes to a thickness of 0.035 mm, the rolling force is 500 KN, the rolling speed is 400 m / min, and the tension is 5 KN; (5) Secondary cleaning: Cleaning is carried out in a degreaser at a cleaning speed of 60 m / min to remove the residual rolling oil; (6) Surface treatment: The foils after cleaning in step (4) are subjected to surface treatment to obtain high-strength CuNiSi alloy rolled copper foils for communication connectors; the surface treatment includes electrolytic degreasing, pickling, roughening, curing, anti-oxidation, and passivation; the conditions for electrolytic degreasing are: temperature 50°C, sodium hydroxide 40 g / L, sodium carbonate 15 g / L, current density 6 A / dm²; the pickling conditions are: sulfuric acid concentration 150 g / L; the roughening sulfuric acid concentration is 150 g / L, copper ion concentration is 15 g / L, plating solution temperature is 20°C, current density is 30 A / dm²; the curing conditions are sulfuric acid concentration 100 g / L, copper ion concentration 50 g / L, plating solution temperature 40°C, current density 20 A / dm²; the anti-oxidation conditions are: temperature 25°C, zinc ion concentration 5 g / L, nickel ion concentration 5 g / L, pH value 9, current density 5 A / dm²; the passivation conditions are: passivation temperature 15°C, chromium ion concentration 5 g / L, pH value 9, current density 4 A / dm².

[0023] Comparative Example 1 Compared with Example 1, the annealing conditions in step (3) of Comparative Example 1 were holding at 450°C for 6 h, and the other conditions were the same as those in Example 1, and CuNiSi alloy rolled copper foils were prepared.

[0024] Performance test: The tensile strength, elongation, hardness, and conductivity of the CuNiSi alloy rolled copper foils prepared in Examples 1 to 3 and Comparative Example 1 were tested, and the results are shown in Table 1 below: Table 1 .

Claims

1. A method for preparing high-strength CuNiSi alloy rolled copper foil for communication connectors, characterized in that: The following steps are involved: (1) Finish rolling: The CuNiSi alloy base material is finished rolled 2 to 3 times, and the total pass power is 45 to 60%; (2) Cleaning: Clean and degrease, and package with soft copper foil; (3) Annealing: 600~800℃ for 4~6h; (4) Finished product rolling: 2 to 6 passes, with a total processing rate of 40 to 85%; (5) Secondary cleaning: cleaning and degreasing; (6) Surface treatment: Surface treatment is performed on the foil after cleaning in step (4).

2. The method for preparing the high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: Step (1) The CuNiSi alloy matrix material is composed of the following components in percentage by weight: Ni 2-3%, Si 0.4-0.8%, Mg 0.05-0.3%, and the balance Cu.

3. The method for preparing the high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: The CuNiSi alloy base material has a thickness of 0.1-0.4 mm, a tensile strength of ≥400 MPa, an elongation of ≥10%, a hardness of ≥120 HV, and a conductivity of ≥50% IACS.

4. The method for preparing high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: The finishing rolling conditions in step (1) are: rolling force 600-1100 KN, rolling speed 200-500 m / min, and tension 5-9.5 KN.

5. The method for preparing high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: The heating rate during annealing in step (3) is 60-100°C / h.

6. The method for preparing the high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: The conditions for the finished product rolling in step (4) are: rolling force 500-900 KN, rolling speed 300-600 m / min, and tension 2-7.5 KN.

7. The method for preparing high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: In step (2) and step (5), the cleaning speed is 50-100 m / min, and the solution temperature is 20-40°C.

8. The method for preparing high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 1, characterized in that: The surface treatment in step (6) includes electrolytic degreasing, pickling, roughening, curing, anti-oxidation and passivation.

9. The method for preparing high-strength CuNiSi alloy rolled copper foil for communication connector according to claim 8, characterized in that: The electrolytic degreasing conditions are: temperature 40-60℃, sodium hydroxide 30-50g / L, sodium carbonate 15-30g / L, current density 4-12A / dm²; the pickling conditions are: sulfuric acid concentration 100-250g / L; roughening sulfuric acid concentration 100-300g / L, copper ion concentration 10-20g / L, plating solution temperature 15-30℃, current density 25-55A / dm²; the curing conditions are sulfuric acid concentration 80-200g / L, copper ion concentration 40-70 g / L, plating solution temperature 30-60℃, current density 10-30A / dm²; the anti-oxidation conditions are: temperature 25-35℃, zinc ion concentration 1-10g / L, nickel ion concentration 1-10g / L, pH value 9-13, current density 2-15A / dm²; the passivation conditions are: passivation temperature 15-30℃, chromium ion concentration 1-10g / L, pH value 8-12, current density 3-8A / dm².

10. A high-strength CuNiSi alloy rolled copper foil for communication connectors prepared by the preparation method according to any one of claims 1 to 9.