A multiple silver-copper lateral composite strip for high-voltage fuse and its preparation method

Abstract

The present invention discloses a plurality of silver-copper lateral composite strips for high-voltage fuses and a preparation method thereof. The method comprises: regulating the properties of the pure copper and pure silver composite components through microalloying to improve the oxidation resistance of the pure copper and to make the deformation properties of the silver and copper components more similar; preparing the microalloyed copper and pure silver into copper bars and silver bars through continuous casting, vacuum melting, and rolling; then slotting the copper bars and coating the composite interface with the silver alloy bars with an organic additive to prepare a composite blank; initial rolling on a two-roll mill to bring the bonding interface into close contact; then sintering in a protective atmosphere to form an interface layer; and finally, subjecting the sintered composite blank to intermediate rolling, diffusion annealing, rolling, pre-finish heat treatment, and finish rolling to prepare a plurality of silver-copper lateral composite strips; and slotting the copper bars along their length. The method employs an organic additive to treat the silver-copper composite interface, thereby resolving the problem of easy oxidation at the composite interface. The silver-copper composite interface is securely bonded, while requiring minimal equipment and being suitable for mass production.

Description

Technical Field

[0001] The present invention belongs to the technical field of composite material preparation, and in particular relates to a plurality of silver-copper lateral composite strips for high-voltage fuses and a preparation method thereof. Background Art

[0002] A fuse is an electrical device that uses a metal conductor as a fuse to protect circuits. Connected in series, it heats up and melts when an overload or short-circuit current flows through the fuse, protecting the power system, various electrical equipment, and household appliances.

[0003] Pure silver ribbon is a widely used high-melting-point melt material. Silver melt has excellent short-circuit current interruption capabilities. Ag is chemically stable and exhibits excellent oxidation and corrosion resistance. Its resistance value rarely changes during use, and its melting point remains stable, ensuring circuit stability and safety. It is a key material for high-current, high-reliability fuses. However, over time, particularly in high- and low-voltage power distribution systems and the new energy vehicle industry, several shortcomings have emerged. First, pure silver is expensive, contributing to the high cost of electrical products. Second, pure silver itself has weak arc-extinguishing capabilities, requiring the use of an arc-extinguishing dielectric. Failure or malfunction of this dielectric can pose a fire or even explosion hazard. Furthermore, pure silver, as a melt material, has a high melting point, resulting in a high temperature rise and slow melting under current overload. Furthermore, the consumption of silver ribbon, the raw material for fast-acting fuses, has also increased dramatically, with its price quadrupling in the past two years. This has undoubtedly put significant pressure on manufacturers, leading them to focus on finding new, lower-cost materials that do not compromise performance. Therefore, developing a melt material with good conductivity, strong arc extinguishing ability, low cost, suitable melting point and good processing performance has become an engineering problem that needs to be solved urgently in fuse manufacturing.

[0004] To address the problems currently exposed during the use of melt materials, fuse manufacturers have proposed various methods, such as using copper alloys and silver-copper alloys instead of pure silver strip. Others have exploited the "metallurgical effect" by designing solder joints with low-melting-point materials such as SnPb on the melt. When overloaded, the low-melting-point material melts and reacts with silver, producing a eutectic alloy with a lower melting point. This causes the pure silver melt to fuse more quickly, quickly disconnecting the protection circuit. While these methods have partially addressed the problem, the issue of low reliability remains unresolved. Summary of the Invention

[0005] The present invention aims to overcome the above-mentioned shortcomings and provides a plurality of silver-copper lateral composite strips for high-voltage fuses and a preparation method thereof. The silver-copper lateral composite strips have a firm composite interface, the silver bar width and the relative position accuracy of the silver bar and the copper bar are high, the rolling process is cold rolling, the product batch stability is high, and the preparation process equipment is simple. The problems of unreliable silver-copper lateral composite interface bonding and difficult control of silver bar width and the relative position accuracy of the silver bar and the copper bar are solved. The plurality of silver-copper lateral composite strips prepared have a reliable composite interface bonding and high dimensional accuracy, and can be widely used as melt materials for high-voltage fast fuses of new energy vehicles and power distribution systems.

[0006] According to a first aspect, the present invention provides a plurality of silver-copper lateral composite strips for a high-voltage fuse, wherein the composite strips are prepared by the following method:

[0007] 1. Prepare the copper bars by continuous casting and smelting according to the following mass percentages.

[0008] (1) Ingredients

[0009] Ag: 0.05%~0.1%, Ce: 0.01%~0.05%, the balance is Cu;

[0010] (2) Cast copper busbar

[0011] Ce is added in the form of a CuCe20 master alloy and continuously cast in a rectangular high-purity graphite mold. The copper busbar width A ranges from 50 to 250 mm, and the thickness H ranges from 15 to 40 mm. Five to ten grooves are then machined along the length of the busbar to meet the product's bar width and spacing requirements. The groove width a ranges from 2.5 to 4.5 mm, and the depth h is 85% to 90% of the busbar thickness H.

[0012] 2. Use vacuum induction furnace to melt and cast silver alloy ingots according to the following mass percentages.

[0013] (1) Ingredients

[0014] Cu: 0.1%~0.3%, Ce: 0.01%~0.05%, Sn: 0.05%~0.1%, La: 0.01%~0.05%, P: 0.001%~0.01%, the balance is Ag;

[0015] (2) Melting and casting silver alloy ingots

[0016] Cu, Ce, and La are added in the form of a CuCeLa mixed rare earth master alloy, and P is added in the form of a CuP master alloy. The ingots are melted in a vacuum induction furnace and then hot-extruded, rolled, subjected to intermediate heat treatment, and finished rolled into silver bars. The width of the silver bar is the width of the copper busbar groove a-(0.03-0.1) mm, and the thickness H1 of the silver bar is the depth of the copper busbar groove h+(0.05-0.2) mm.

[0017] 3. Add two or more organic acids such as malonic acid, malic acid, citric acid, tartaric acid, and stearic acid to a mixed organic solvent of two or more, such as ethylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, propylene glycol, and butyl carbitol, and heat to dissolve at a temperature of 50°C to 70°C. After complete dissolution, add one or more additives such as diethanolamine, triethanolamine, castor oil, Span 85, and Tween 60. Stir evenly and cool to form a paste. Apply the paste to the surface of the copper busbar groove and the silver bar. Insert the silver bar coated with the organic additive into the copper busbar groove to assemble the silver-copper composite blank.

[0018] 4. Use a two-roll mill to initially roll the composite billet, with a total deformation of 5-10%;

[0019] 5. Sinter the composite billet after initial rolling in a tubular furnace under protective atmosphere at a sintering temperature of 600°C to 800°C for 1 to 3 hours. The protective atmosphere is one of nitrogen, argon, and hydrogen.

[0020] 6. The sintered composite billet is rolled on a precision four-roller rolling mill with a pass deformation of 5% to 10% and a total deformation of 40% to 70%.

[0021] 7. After intermediate rolling, the composite billet is subjected to diffusion annealing in a protective atmosphere of a tubular furnace. The diffusion annealing temperature range is 400°C to 700°C, the holding time is 0.5 to 4 hours, and the protective atmosphere is one of nitrogen, argon, and hydrogen. Repeat steps 6 and 7 above. After 3 to 5 annealing and rolling, the billet is rolled to a thickness of 3.0 ±0.1 mm;

[0022] 8. Intermediate surface treatment and rolling: The diffusion annealed composite sheet is surface treated using a strip grinder. After grinding, the bottom silver strip is exposed and the width of the silver strip is consistent with that of the front. The leader strip is then welded using a spot welder and rolled using a four-roller tight rolling mill with tension. The deformation per pass is 10-20%, and the total deformation between the two annealing passes is controlled between 40% and 70%. The tension is controlled between 1.5 kN and 4 kN, and the rolling speed is controlled between 5 m / min and 20 m / min.

[0023] 9. Annealing and shearing before finished products: According to the finished product size, tensile strength and hardness requirements, a vertical vacuum annealing furnace is used for heat treatment before finished products. The annealing before finished products is carried out in a vacuum pit furnace. The diffusion annealing temperature range is 400℃~500℃, the holding time is 0.5~2h, and the vacuum degree is less than 10 -1Pa; Pre-cutting of finished products uses a precision strip shearing machine to shear the edges of the strip to ensure that the overall width of the strip and the width of the copper bars on both sides meet the requirements of the finished product. The strip shearing tension is controlled between 0.5KN and 1.5KN, and the rolling speed is controlled between 3m / min and 10m / min.

[0024] 10. Finishing rolling of finished products: Tension rolling is performed on a precision six-roller rolling mill, with a pass deformation of 5-10%, a total deformation controlled between 40% and 60%, a tension controlled between 0.5 kN and 1.5 kN, and a rolling speed controlled between 3 m / min and 10 m / min. After finishing rolling, the finished products are sheared off, cleaned, inspected, and packaged to produce multiple silver-copper composite strip products.

[0025] Beneficial effects of the present invention:

[0026] The present invention adopts microalloying technology to regulate the performance of silver-copper composite substrate, applies organic composite additives on the composite interface to effectively remove the surface oxide film, and adopts the combined technology of coated composite billet preparation technology and protective atmosphere sintering to achieve the coexistence and mutual promotion of two mechanisms of physical mechanical bite pinning and chemical element diffusion connection at the silver-copper composite interface. The composite interface bonding is firm and reliable. At the same time, the coating structure composite ingot structure is adopted to avoid direct contact between the silver bar and the roller before the finished product is finished. The silver bar is in a three-dimensional compression state during the rolling process, and the stress state is uniform, so that the stress state of multiple silver bars is basically consistent, ensuring uniform deformation, thereby improving the width of the silver bar and the relative position accuracy of the silver and copper bars. The problems of unreliable silver-copper lateral composite interface bonding and difficult to control the silver bar width and the relative position accuracy of the silver bar and the copper bar are solved. The multiple silver-copper lateral composite strips prepared have reliable composite interface bonding and high dimensional accuracy, and can be widely used as melt materials for high-voltage fast fuses in new energy vehicles and power distribution systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings in the specification are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0028] Figure 1 This is a physical picture of five silver-copper lateral composite strips prepared in Example 1 of the present invention;

[0029] Figure 2 This is a physical picture of 8 silver-copper lateral composite strips prepared by the method of the present invention. DETAILED DESCRIPTION

[0030] Example 1

[0031] The present invention provides a method for preparing multiple silver-copper lateral composite strips for high-voltage fuses, comprising the following steps:

[0032] 1. Continuous casting and melting of copper bars are carried out by continuous casting process according to the following mass percentage: Ag: 0.08%~0.1%, Ce: 0.01%~0.05%, and the balance is Cu; Ce is added in the form of CuCe20 master alloy, and continuous casting is carried out in a rectangular high-purity graphite crystallizer. The width A of the copper bar is 80 ±0.5 mm, thickness H is 15 ±0.1 Then, 5 grooves are machined in the length direction of the copper bar according to the product silver bar width and spacing requirements. The width a of the groove is 2.5 ±0.05 mm, depth h is 12 ±0.1 mm;

[0033] 2. Silver alloy ingots are melted and cast in a vacuum induction furnace according to the following mass percentages: Cu: 0.1%~0.3%, Ce: 0.01%~0.05%, Sn: 0.05%~0.1%, La: 0.01%~0.05%, P: 0.001%~0.01%, and the balance is Ag; Cu, Ce, and La are added in the form of a CuCeLa mixed rare earth master alloy, and P is added in the form of a CuP10 master alloy. The ingots are melted in a vacuum induction furnace and hot extruded, rolled, subjected to intermediate heat treatment, and finished rolled into silver bars. The thickness of the silver bars is H1, which is 2.45 ±0.05 mm, the width of the silver bar is 12.1 ±0.1mm ;

[0034] 3. Add two or more organic acids such as malonic acid, malic acid, citric acid, tartaric acid, and stearic acid to a mixed organic solvent of two or more such as ethylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, propylene glycol, and butyl carbitol, and heat to dissolve at a dissolution temperature of 50° C. After complete dissolution, add two or more additives such as diethanolamine, triethanolamine, castor oil, Span 85, and Tween 60, stir evenly, and cool to form a paste. Apply the paste-like composite agent to the surface of the copper busbar groove and the surface of the silver bar. Insert the silver bar coated with the organic composite agent into the copper busbar groove to assemble into a silver-copper composite blank.

[0035] 4. The composite billet is initially rolled using a two-roll mill with a total deformation of 5-10%. The thickness of the composite billet after rolling is 14 ±0.1 mm;

[0036] 5. The composite billet after initial rolling is sintered in a tubular furnace with a protective atmosphere at a sintering temperature of 600°C and a holding time of 3 hours in a hydrogen protective atmosphere;

[0037] 6. The sintered composite billet is rolled on a precision four-roller rolling mill with a pass deformation of 5% to 10% and a total deformation of 40%;

[0038] 7. The composite billet after intermediate rolling is subjected to diffusion annealing in a tubular furnace with a protective atmosphere. The diffusion annealing temperature is 400°C, the holding time is 4 hours, and the protective atmosphere is hydrogen. Repeat steps 6 and 7 above. After annealing and rolling for 3 times, the billet is rolled to a thickness of 3.0 ±0.1 mm;

[0039] 8. Intermediate surface treatment and rolling: The composite plate after diffusion annealing is surface treated by using a strip grinder. After grinding, the bottom silver strip is exposed and the width of the silver strip is consistent with the front. Then, a spot welder is used to weld the leader strip and a four-roller tight rolling mill is used for strip tension rolling. The pass deformation is 10%, and the total deformation between the two annealings is controlled at 50%. The tension is controlled between 1.5KN and 2.0KN, and the rolling speed is controlled at 5m / min. After three annealing and rolling, the thickness is rolled to 0.2mm.

[0040] 9. Annealing and shearing before finished products: According to the finished product size, tensile strength and hardness requirements, a vertical vacuum annealing furnace is used for heat treatment before finished products. The annealing before finished products is carried out in a vacuum pit furnace with an annealing temperature of 400°C, a holding time of 0.5, and a vacuum degree of less than 10 -1 Pa; Pre-cutting of finished products uses a precision strip shearing machine to shear the edges of the strip to ensure that the overall width of the strip and the width of the copper bars on both sides meet the requirements of the finished product. The strip shearing tension is controlled between 0.5KN and 1.5KN, and the rolling speed is controlled between 3m / min and 10m / min.

[0041] 10. Finished product rolling: adopt precision six-roll rolling mill with tension rolling, the deformation of each pass is 5~10%, the total deformation is controlled at about 40%, the tension is controlled between 0.5KN~0.7KN, the rolling speed is controlled between 3m / min~4m / min, and the thickness of the finished product after rolling is 0.11 ±0.01 mm, the finished product is cut off after finishing rolling, and then cleaned, inspected and packaged to obtain 5 silver-copper composite strip products (such as Figure 1 shown).

[0042] Example 2

[0043] The present invention provides a method for preparing multiple silver-copper lateral composite strips for high-voltage fuses, comprising the following steps:

[0044] 1. Continuous casting and melting of copper bars is carried out by continuous casting process according to the following mass percentage: Ag: 0.08%~0.1%, Ce: 0.01%~0.05%, and the balance is Cu; Ce is added in the form of CuCe20 master alloy, and continuous casting is carried out in a rectangular high-purity graphite crystallizer. The width of the copper bar A is 200 ±1.0 mm, thickness H is 40 ±0.1Then, five grooves are machined in the length direction of the copper bar according to the product silver bar width and spacing requirements. The width a of the groove is 4.5 ±0.05 mm, depth h is 36 ±0.1 mm;

[0045] 2. Silver alloy ingots are melted and cast in a vacuum induction furnace according to the following mass percentages: Cu: 0.1%~0.3%, Ce: 0.01%~0.05%, Sn: 0.05%~0.1%, La: 0.01%~0.05%, P: 0.001%~0.01%, and the balance is Ag; Cu, Ce, and La are added in the form of a CuCeLa mixed rare earth master alloy, and P is added in the form of a CuP10 master alloy. The ingots are melted in a vacuum induction furnace and then subjected to hot extrusion, rolling, intermediate heat treatment, and finish rolling to form silver bars. The thickness of the silver bars is H1, which is 4.45 mm. ±0.05 mm, the width of the silver bar is 36.2 ±0.1mm ;

[0046] 3. Add two or more organic acids such as malonic acid, malic acid, citric acid, tartaric acid, and stearic acid to a mixed organic solvent of two or more such as ethylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, propylene glycol, and butyl carbitol, and heat to dissolve at 70°C. After complete dissolution, add two or more additives such as diethanolamine, triethanolamine, castor oil, Span 85, and Tween 60. Stir well and cool to form a paste. Apply the paste-like composite agent to the surface of the copper busbar groove and the surface of the silver bar. Insert the silver bar coated with the organic composite agent into the copper busbar groove to assemble into a silver-copper composite blank.

[0047] 4. The composite billet is initially rolled using a two-roll mill with a total deformation of 5-10%. The thickness of the composite billet after rolling is 38 ±0.2 mm;

[0048] 5. The composite billet after initial rolling is sintered in a tubular furnace under protective atmosphere at a sintering temperature of 770°C and a holding time of 0.5h in an argon protective atmosphere;

[0049] 6. The sintered composite billet is rolled on a precision four-roller rolling mill with a pass deformation of 5% to 10% and a total deformation of 60%;

[0050] 7. The composite billet after intermediate rolling is subjected to diffusion annealing in a tubular furnace with a protective atmosphere. The diffusion annealing temperature is 600°C, the holding time is 4 hours, and the protective atmosphere is argon. Repeat steps 6 and 7 above. After secondary annealing and rolling, the billet is rolled to a thickness of 3.0 ±0.1 mm;

[0051] 8. Intermediate surface treatment and rolling: The composite plate after diffusion annealing is surface treated by using a strip grinder. After grinding, the bottom silver strip is exposed and the width of the silver strip is consistent with the front. Then, a spot welder is used to weld the leader strip and a four-roller tight rolling mill is used for strip tension rolling. The pass deformation is 10%, and the total deformation between the two annealings is controlled at 50%. The tension is controlled between 1.5KN and 2.0KN, and the rolling speed is controlled at 10m / min. After three annealing and rolling, the thickness is rolled to 0.2mm.

[0052] 9. Annealing and shearing before finished products: According to the finished product size, tensile strength and hardness requirements, a vertical vacuum annealing furnace is used for heat treatment before finished products. The annealing before finished products is carried out in a vacuum pit furnace with an annealing temperature of 500°C, a holding time of 1 hour, and a vacuum degree of less than 10 -1 Pa; Pre-cutting of the finished product uses a precision strip shearing machine to shear the edges of the strip to ensure that the overall width of the strip and the width of the copper bars on both sides meet the requirements of the finished product. The strip shearing tension is controlled between 0.5KN and 1.0KN, and the rolling speed is controlled between 8m / min and 10m / min.

[0053] 10. Finished product rolling: adopt precision six-roll rolling mill with tension rolling, the deformation of each pass is 5~10%, the total deformation is controlled at about 70%, the tension is controlled between 0.5KN~0.7KN, the rolling speed is controlled between 8m / min~10m / min, and the thickness of the finished product after rolling is 0.05 ±0.005 mm, after the finished product is finish-rolled, the head and tail are cut off, and after cleaning and inspection, 10 silver-copper composite strip products are packaged.

Claims

1. A method for preparing multiple silver-copper lateral composite strips for high-voltage fuses, characterized in that: The following steps are involved: Step 1: Prepare the copper bars by continuous casting and melting according to the following mass percentages: Ingredients: Ag wt%: 0.05%~0.1%, Ce wt%: 0.01%~0.05%, the balance is Cu; Casting copper busbars: Ce is added in the form of a CuCe20 master alloy and continuously cast in a rectangular high-purity graphite mold. The copper busbar width A ranges from 50 to 250 mm, and the thickness H ranges from 15 to 40 mm. Five to ten grooves are then machined along the length of the busbar to meet the silver bar width and spacing requirements. The groove width a ranges from 2.5 to 4.5 mm, and the depth h is 85% to 90% of the copper busbar thickness H. Step 2: Using a vacuum induction furnace to melt and cast silver alloy ingots according to the following mass percentages: Ingredients: Cu wt%: 0.1%~0.3%, Ce wt%: 0.01%~0.05%, Sn wt%: 0.05%~0.1%, La wt%: 0.01%~0.05%, P wt%: 0.001%~0.01%, and the balance is Ag; Melting and casting silver alloy ingots: Cu, Ce, and La are added in the form of CuCeLa mixed rare earth master alloy, and P is added in the form of CuP master alloy. The ingots are melted and cast in a vacuum induction furnace, and then hot extruded, rolled, subjected to intermediate heat treatment, and finished rolled into silver bars. The width of the silver bar is the width of the copper busbar groove a-(0.03~0.1)mm, and the thickness H1 of the silver bar is the depth of the copper busbar groove h+(0.05~0.2)mm; Step 3, adding two or more of malonic acid, malic acid, citric acid, tartaric acid, and stearic acid to two or more of ethylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, propylene glycol, and butyl carbitol, mixing and heating to dissolve, adding one or more additives selected from diethanolamine, triethanolamine, castor oil, Span 85, and Tween 60 after complete dissolution, stirring and cooling to form a paste, applying the paste additive to the surface of the copper busbar groove and the surface of the silver bar to remove the surface oxide film, and inserting the silver bar coated with the organic additive into the copper busbar groove to assemble into a silver-copper composite blank; Step 4: The composite blank is initially rolled using a two-roll rolling mill with a total deformation of 5% to 10%; Step 5, sintering the composite billet after primary rolling in a protective atmosphere of a tubular furnace and keeping it warm; Step 6: The sintered composite billet is rolled using a precision four-roller rolling mill, with a pass deformation of 5% to 10% and a total deformation of 40% to 70%; Step 7, diffusion annealing the composite billet after intermediate rolling in a protective atmosphere of a tubular furnace and keeping it warm; Step 8: Repeat steps 6 and 7 above, and after 3 to 5 rolling and annealing, roll the steel sheet to a thickness of 2.9 mm to 3.1 mm. Step 9, intermediate surface treatment and rolling: The diffusion annealed composite sheet is surface treated, then welded with a leader strip and subjected to strip tension rolling using a four-roller compact rolling mill, with a pass deformation of 10-20%, and the total deformation between the two annealings controlled between 40% and 70%; Step 10, annealing and shearing before finishing; Step 11: The deformation of each pass is 5% to 10%, and the total deformation is controlled between 40% and 60%, and a plurality of silver-copper composite strip products are obtained by finish rolling.

2. The preparation method according to claim 1, wherein: In step 3, the heating and dissolving temperature is 50°C to 70°C.

3. The preparation method according to claim 1, wherein: In step 5, the sintering temperature is 600° C. to 800° C., the holding time is 1 to 3 hours, and the protective atmosphere is one of nitrogen, argon and hydrogen.

4. The preparation method according to claim 1, wherein: In step 7, the diffusion annealing temperature range is 400° C. to 700° C., the holding time is 0.5 to 4 hours, and the protective atmosphere is one of nitrogen, argon and hydrogen.

5. The preparation method according to claim 1, wherein: In step 9, a strip grinder is used for surface treatment, so that the bottom silver bar is exposed after grinding and the width of the silver bar is consistent with that of the front side.

6. The preparation method according to claim 1, wherein: In step 9, the tension of the strip tension rolling is controlled between 1.5 KN and 4 KN, and the rolling speed is controlled between 5 m / min and 20 m / min.

7. The preparation method according to claim 1, characterized in that In step 10, the pre-finishing annealing includes: According to the finished product size and tensile strength and hardness requirements, a vertical vacuum annealing furnace is used for pre-finished product heat treatment. The pre-finished product annealing adopts a vacuum pit furnace. The diffusion annealing temperature range is 400℃~500℃, the holding time is 0.5~2h, and the vacuum degree is less than 10 -1 Pa.

8. The preparation method according to claim 1, characterized in that In step 10, the shearing includes: A precision strip shearing machine is used to shear the edges of the strip to ensure that the overall width of the strip and the width of the copper bars on both sides meet the requirements of the finished product. The strip shearing tension is controlled between 0.5KN and 1.5KN, and the rolling speed is controlled between 3m / min and 10m / min.

9. The preparation method according to any one of claims 1 to 8, characterized in that In step 11, the finishing rolling includes: A precision six-roller rolling mill is used for strip tension rolling, with the tension controlled between 0.5KN and 1.5KN and the rolling speed controlled between 3m / min and 10m / min. After the finished product is finish-rolled, the head and tail are cut off and the product is cleaned, inspected, and then packaged to obtain multiple silver-copper composite strip products.

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