A copper-clad aluminum wire and a preparation method thereof, a cable and a preparation method thereof

Abstract

The application discloses a copper-clad aluminum wire and a preparation method thereof, and a cable and a preparation method thereof, and relates to the technical field of cables.The copper-clad aluminum wire comprises an aluminum core, a transition metal layer and a copper cladding layer arranged in sequence from inside to outside.In the technical scheme, the aluminum core, the transition metal layer and the copper cladding layer take into account the lightweight and low-cost advantages of aluminum and the high conductivity and corrosion resistance advantages of copper, and the problem that aluminum and copper are directly combined and prone to wire cracks due to stress concentration and long-term use of the risk of layering is solved through the transition metal layer.

Description

Technical Field

[0001] This invention relates to the field of cable technology, and in particular to a copper-clad aluminum conductor and its preparation method, and a cable and its preparation method. Background Technology

[0002] With the popularization of new energy vehicles and intelligent technologies, lightweighting of the entire vehicle has become key to improving range and energy efficiency. Copper has a density of approximately 8.89 g / cm³. 3 Aluminum, however, is only 2.7 g / cm³. 3 Copper-clad aluminum conductors, through their structural design of an aluminum core wrapped with a copper layer, significantly reduce weight while maintaining conductivity.

[0003] Existing copper-clad aluminum conductors are prone to microcracks at the copper-aluminum interface after stranding due to stress concentration. Long-term use poses a risk of delamination. When vibrations occur during vehicle operation, the stress concentration area is prone to metal fatigue, resulting in a high wire breakage rate. Summary of the Invention

[0004] The main objective of this invention is to provide a copper-clad aluminum conductor and its preparation method, as well as a cable and its preparation method, in order to solve the problem that copper-clad aluminum conductors are prone to delamination at the copper-aluminum interface after stranding, resulting in a high wire breakage rate.

[0005] To achieve the above objectives, the present invention proposes a copper-clad aluminum conductor, comprising an aluminum core, a transition metal layer, and a copper cladding layer arranged sequentially from the inside to the outside.

[0006] In one embodiment, the transition metal layer is plated on the inner side of the copper cladding layer and welded to the aluminum core.

[0007] In one embodiment, the alloy transition layer comprises a Sn-Mg alloy transition layer.

[0008] In one embodiment, the aforementioned method for preparing copper-clad aluminum conductors includes the following steps: S1. A transition metal layer is plated on one side of the copper strip to form a composite copper strip; S2. The side of the composite copper strip with the transition metal layer is wrapped around the outer surface of the preheated aluminum core. The transition metal layer is introduced into the copper-aluminum interface by composite rolling and diffusion welding. After rapid cooling, the copper-clad aluminum conductor is annealed in a protective atmosphere to form the copper-clad aluminum conductor.

[0009] In one embodiment, the plating method in step S1 is electroplating.

[0010] In one embodiment, in step S1, the temperature of the preheated aluminum core is 240~260°C.

[0011] In one embodiment, in step S1, the welding temperature is 380~420°C and the time is 8~12 minutes.

[0012] In one embodiment, the annealing step S2 specifically involves heating from room temperature to 280-320°C at a heating rate of 4-6°C / min, holding at that temperature for 15-25 minutes, and then cooling it with the furnace.

[0013] The present invention also provides a cable, which is formed by twisting multiple copper-clad aluminum conductors in the same direction.

[0014] In one embodiment, the cable includes an intermediate layer and a plurality of outer layers, the intermediate layer including one of the said conductors, and each of the outer layers including a plurality of the said copper-clad aluminum conductors.

[0015] The present invention also provides a method for manufacturing a cable, comprising the following steps: S10. Provide a plurality of copper-clad aluminum conductors as described in any of the above, wherein the plurality of copper-clad aluminum conductors include a central copper-clad aluminum conductor and a peripheral copper-clad aluminum conductor, wherein the diameter of the central copper-clad aluminum conductor is larger than that of the peripheral copper-clad aluminum conductor. S20. Position the center copper-clad aluminum wire through the first mold on the first wire distribution plate; S30. Multiple peripheral copper-clad aluminum conductors are arranged around the periphery of the central copper-clad aluminum conductor, and at least one outer layer is formed by twisting them in the same direction.

[0016] In one embodiment, forming at least one outer layer by stranding multiple peripheral copper-clad aluminum conductors around the central copper-clad aluminum conductor in the same direction specifically includes: guiding multiple peripheral copper-clad aluminum conductors through a mold and a wire divider, distributing them circumferentially around the central copper-clad aluminum conductor by controlling the stranding angle and pitch ratio, adjusting the tension of the copper-clad aluminum conductors by combining tension feedback, and stranding them in the same direction to form at least one outer layer.

[0017] In the technical solution of this invention, the aluminum core, the transition metal layer, and the copper cladding layer combine the advantages of aluminum in terms of lightweight and low cost with the advantages of copper in terms of high conductivity and corrosion resistance. The transition metal layer solves the problem that direct aluminum-copper composite is prone to wire cracking due to stress concentration and the risk of delamination during long-term use. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a cross-sectional schematic diagram of an embodiment of the copper-clad aluminum conductor of the present invention; Figure 2 This is a schematic flowchart of an embodiment of the method for manufacturing the conductor of the present invention; Figure 3 This is a cross-sectional schematic diagram of an embodiment of the cable of the present invention; Figure 4 for Figure 3 A schematic diagram of the layered twisting of the cables in the diagram; Figure 5 This is a schematic flowchart illustrating an embodiment of the cable manufacturing method of the present invention. Attached image description: 1. Aluminum core; 2. Transition metal layer; 3. Copper cladding layer; 11. First floor; 12. Second floor; 13. Third floor; 14. Fourth floor; 100. Copper-clad aluminum conductor; 20. First dividing board; 21. Second dividing board; 22. Third dividing board; 23. Fourth dividing board; 30. First mold; 31. Second mold; 32. Third mold; 33. Fourth mold.

[0021] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially. Furthermore, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, or solution B, or a solution where both A and B are satisfied simultaneously. In addition, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] With the popularization of new energy vehicles and intelligent technologies, lightweighting of the entire vehicle has become key to improving range and energy efficiency. Copper has a density of approximately 8.89 g / cm³. 3 Aluminum, however, is only 2.7 g / cm³. 3Copper-clad aluminum conductors, through their structural design of an aluminum core wrapped with a copper layer, significantly reduce weight while maintaining conductivity.

[0024] However, existing copper-clad aluminum conductors are prone to microcracks at the copper-aluminum interface after stranding due to stress concentration. Long-term use poses a risk of delamination. When vibrations occur during vehicle operation, the stress concentration area is prone to metal fatigue, resulting in a high wire breakage rate.

[0025] In view of this, the present invention provides a copper-clad aluminum conductor 100, which includes an aluminum core 1, a transition metal layer 2, and a copper cladding layer 3 arranged sequentially from the inside to the outside, as shown in the figure. Figure 1 As shown.

[0026] In the technical solution of the present invention, the aluminum core 1, the transition metal layer 2 and the copper cladding layer 3 take into account the advantages of aluminum in terms of lightweight and low cost and the advantages of copper in terms of high conductivity and corrosion resistance. The transition metal layer 2 solves the problem that direct composite of aluminum and copper is prone to wire cracking due to stress concentration and the risk of delamination during long-term use.

[0027] The connection between the transition metal layer 2 and the aluminum core 1 and the copper cladding layer 3 can be varied. In some embodiments of the present invention, the transition metal layer 2 is plated on the inner side of the copper cladding layer 3 and welded to the aluminum core 1. Obviously, this design is not limited to this; the transition metal layer 2 can also be welded to both the copper cladding layer 3 and the aluminum core 1 simultaneously.

[0028] In this embodiment, the copper cladding layer 3 is welded to the aluminum core 1. This is mainly because the melting point of copper is higher than that of aluminum and the transition metal layer 2. Therefore, the transition metal layer 2 can be plated onto the copper cladding layer 3 first, and then welded to the aluminum core 1. During the high-temperature welding process, the copper cladding layer 3 is not affected, thereby ensuring the integrity of the conductor's shape. Furthermore, the metallurgical bonding layer formed by welding is a continuous integral structure without gaps or holes where stress concentration occurs, resulting in better impact resistance, fatigue resistance, and sealing performance.

[0029] The transition metal layer 2 serves to connect the aluminum core 1 and the copper cladding layer 3. Its specific composition is not limited. For example, the transition metal layer 2 includes Sn-Zn transition metal layer 2, Sn-Al transition metal layer 2, Sn-Cu transition metal layer 2, Zn-Al transition metal layer 2, and Ag-Cu transition metal layer 2. It can form stable metallurgical bonding interfaces with the aluminum core 1 and the copper cladding layer 3 respectively, which can alleviate the interface stress concentration problem caused by direct copper-aluminum composite, improve the interface bonding strength and long-term service reliability.

[0030] In some embodiments of the present invention, the alloy transition layer is a Sn-Mg alloy transition layer. The Sn-Mg alloy transition layer can be formed to absorb thermal cycling stress, thus providing stress buffering and improving interfacial shear strength.

[0031] This invention also provides a method for preparing a copper-clad aluminum conductor 100. Figure 2 This is a schematic flowchart illustrating an embodiment of the manufacturing method of the copper-clad aluminum conductor 100 of the present invention. Please refer to [link / reference]. Figure 2 The preparation method of the copper-clad aluminum conductor 100 includes the following steps: S1. A transition metal layer 2 is plated on one side of the copper strip to form a composite copper strip; S2. The side of the composite copper strip with the transition metal layer 2 is wrapped around the outer surface of the preheated aluminum core 1. The transition metal layer 2 is introduced into the copper-aluminum interface by composite rolling and diffusion welding. After rapid cooling, the copper-clad aluminum conductor 100 is formed under a protective atmosphere.

[0032] In the technical solution of this invention, composite rolling and diffusion welding add an alloy transition layer to form a metallurgical bonding layer and an intermetallic compound reinforcement skeleton, thereby improving the interfacial shear strength and the strength retention rate after thermal shock.

[0033] In some embodiments of the present invention, in step S1, the plating method is electroplating. The electroplating is performed using a solution containing 20 g / L Sn. 2+ 5g / L Mg 2+ Electroplating is completed in an electrolyte containing a complexing agent, with the current density controlled at 2-3 A / dm³. 2 .

[0034] In the technical solution of this invention, Sn in the electrolyte is removed by electroplating. 2+ With Mg 2+ The reduction rate is synchronous and uniform, avoiding local enrichment of single ions and ensuring that the two elements are deposited synergistically on the copper strip surface, achieving uniform doping of Sn and Mg.

[0035] In some embodiments of the present invention, in step S1, the temperature of the preheated aluminum core 1 is 240~260°C. In the technical solution of this invention, 240~260°C exceeds the melting point of Sn, which enables Sn in the Sn-Mg coating on the surface of the copper strip to liquefy and spread rapidly, forming a Sn / Mg mixed liquid phase; if the temperature is too high, it will cause the aluminum core 1 to deform.

[0036] In some embodiments of the present invention, in step S1, the diffusion welding temperature is 380~420°C and the time is 8~12 min.

[0037] In the technical solution of the present invention, the welding temperature and time ensure that Mg fully reduces the Al2O3 oxide film at the copper-aluminum interface and avoids incomplete reduction caused by insufficient temperature, ensuring that Sn, Cu and Al atoms are in direct contact to form a continuous and stable metallurgical bonding layer.

[0038] In some embodiments of the present invention, in step S2, the annealing process specifically involves raising the temperature from room temperature to 280-320°C at a heating rate of 4-6°C / min, holding the temperature for 15-25 minutes, and then cooling it with the furnace.

[0039] In the technical solution of the present invention, the slow heating at 4~6°C / min can reduce the interfacial stress caused by the difference in thermal expansion between copper and aluminum, and the precise temperature control at 280~320°C can both prevent the aluminum core 1 from overheating and softening and prevent the copper layer from oxidizing.

[0040] The present invention also provides a cable, which is formed by twisting multiple copper-clad aluminum conductors 100 in the same direction.

[0041] In the technical solution of this invention, all copper-clad aluminum conductors 100 are twisted in the same direction to avoid stress collision caused by alternating directions between layers, thus eliminating stress concentration from a structural design perspective. Furthermore, the copper-clad aluminum conductor 100 is the aforementioned copper-clad aluminum conductor 100. The aluminum core 1, transition metal layer 2, and copper cladding layer 3 combine the advantages of aluminum in terms of lightweight and low cost with the advantages of copper in terms of high conductivity and corrosion resistance. The transition metal layer 2 solves the problem that direct composite of aluminum and copper is prone to conductor cracking due to stress concentration, and the risk of delamination during long-term use.

[0042] In some embodiments of the present invention, the cable includes an intermediate layer and multiple outer layers, the intermediate layer including a copper-clad aluminum conductor 100, and each outer layer including multiple copper-clad aluminum conductors 100. Specifically, as... Figure 3 As shown, the cable includes three outer layers. Obviously, this design is not limited to this; the outer layers can be two or more, depending on the actual needs.

[0043] In the technical solution of this invention, the co-directional twisting of each layer ensures that the force on each layer of conductor is balanced and the interlocking force increases layer by layer, reducing the risk of interlayer slippage, better solving the problem of interlayer stress alternation, and reducing the wire breakage rate.

[0044] The present invention also provides a method for manufacturing a cable. Figure 5 For a schematic flowchart of an embodiment of the cable manufacturing method provided by the present invention, please refer to [link / reference]. Figure 5 The method for manufacturing the cable includes the following steps: Step S10: Provide multiple copper-clad aluminum conductors 100 as described above. The multiple copper-clad aluminum conductors 100 include a central copper-clad aluminum conductor 100 and peripheral copper-clad aluminum conductors 100. The diameter of the central copper-clad aluminum conductor 100 is larger than that of the peripheral copper-clad aluminum conductors 100.

[0045] Specifically, in one embodiment, for example, the diameter of the central copper-clad aluminum conductor 100 is 0.3 mm, and the outer copper-clad aluminum conductor is distributed in three layers, namely the second layer 12, the third layer 13, and the fourth layer 14, with diameters of 0.25 mm, 0.22 mm, and 0.20 mm, respectively.

[0046] Step S20: Position the central copper-clad aluminum conductor 100 through the first mold 30 on the first dividing plate 20.

[0047] Specifically, the first dividing plate 20 is provided with a first through hole, and the first mold 30 is disposed in the first through hole. The first mold 30 is a polycrystalline diamond mold.

[0048] Step S30: Multiple peripheral copper-clad aluminum conductors 100 are twisted together in the same direction around the periphery of the central copper-clad aluminum conductor 100 to form at least one outer layer.

[0049] In the technical solution of the present invention, the position is strictly controlled by the first dividing plate 20 and the first mold 30 to ensure that the subsequent monofilaments are evenly distributed around it, thus ensuring the overall concentricity. The central copper-clad aluminum conductor 100 serves as the central axis of the entire conductor bundle, providing basic support for the outer structure and also undertaking the stress buffering function.

[0050] In some embodiments of the present invention, forming at least one outer layer by stranding multiple peripheral copper-clad aluminum conductors 100 around the periphery of the central copper-clad aluminum conductor 100 in the same direction specifically includes: guiding multiple peripheral copper-clad aluminum conductors 100 through a mold and a wire divider, distributing them circumferentially around the central copper-clad aluminum conductor 100 by controlling the stranding angle and pitch ratio, adjusting the tension of the copper-clad aluminum conductors 100 in combination with tension feedback, and stranding them in the same direction to form at least one outer layer.

[0051] Specifically, such as Figure 4 As shown, the second layer 12 includes 6 copper-clad aluminum conductors 100, which are evenly distributed in a circle around the first layer 11; the third layer 13 includes 12 copper-clad aluminum conductors 100, which are evenly distributed in a circle around the second layer 12; and the fourth layer 14 includes 18 copper-clad aluminum conductors 100, which are evenly distributed in a circle around the third layer 13.

[0052] In the technical solution of this invention, tension feedback adjustment is used to avoid wire skipping and breakage, ensuring interlayer adhesion; tight wrapping is achieved through molds, wire separating plates, twisting angles and pitch ratios, improving roundness and reducing the risk of local compression during bending, which could lead to insulation layer damage.

[0053] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0054] Example 1 A copper-clad aluminum conductor 100, consisting of an aluminum core 1, a Sn-Mg alloy transition layer 2, and a copper cladding layer 3 from the inside out, has the following structure: Figure 1 As shown, it is prepared by the following method: Clean the raw copper strip and electroplate a Sn-Mg composite coating onto its surface. The electroplating process involves using a solution containing 20 g / L Sn. 2+ 5g / L Mg 2+ Electroplating is completed in an electrolyte containing a complexing agent, with the current density controlled at 2-3 A / dm³. 2 The aluminum core is preheated to 250°C. A copper strip with a coating is then composite-rolled with the aluminum, followed by vacuum diffusion welding at 400°C. After rapid cooling, a copper-clad aluminum conductor monofilament is formed. Subsequently, a stepped annealing process is used, where the copper-clad aluminum monofilament is heated from room temperature to 300°C at a rate of 5°C / min in an argon-protected atmosphere, held at that temperature for 20 minutes, and then cooled in the furnace to form a copper-clad aluminum conductor 100.

[0055] Performance testing The test results are shown in Table 1. 1. Interface strength testing shall be conducted in accordance with GB / T16491-2008 "Electronic Universal Testing Machine" and ASTM D1002-2010 "Single Lap Joint Shear Strength Test Method"; 2. The strength retention rate after thermal shock shall be tested in accordance with IEC60068-2-14.

[0056] Table 1. Interface strength and post-thermal shock strength retention rate of a copper-clad aluminum conductor in Example 1.

[0057] Example 2 A cable includes 37 copper-clad aluminum conductors 10. Each copper-clad aluminum conductor 10 consists of an aluminum core 1, a Sn-Mg alloy transition layer 2, and a copper cladding layer 3 from the inside out. The Sn-Mg alloy transition layer 2 has a thickness of 0.75 μm. The 37 copper-clad aluminum conductors 10 are layered and twisted in a left-hand direction, forming four layers from the inside out. Its structure is as follows... Figure 3 As shown, it is prepared by the following method: Cable fabrication includes the following steps: The first layer 11 is the central axis of the entire wire harness, containing a copper-clad aluminum wire 10 with a diameter of 0.3mm. The position of the first layer 11 is strictly controlled by the first wire divider 20 (positioning hole accuracy ±0.01mm) and the first mold 30 (hole diameter 0.35±0.015mm). The second layer 12 includes 6 copper-clad aluminum wires 10 with a diameter of 0.25mm. The 6 copper-clad aluminum wires 10 are evenly distributed around the first layer 11 in a circle. They are guided by the second mold 21 (hole diameter 0.85±0.015mm) and the tension of the copper-clad aluminum wires is adjusted by tension feedback. The third layer 13 includes 12 copper-clad aluminum conductors 10 with a diameter of 0.22mm. The 12 copper-clad aluminum conductors 10 are evenly distributed in a circle around the second layer 12, with a twist angle of 25-28°. The fourth layer 14 includes 18 copper-clad aluminum conductors 10 with a diameter of 0.20mm, a twist angle of 30-32°, and a pitch ratio of 8.5. The fourth layer 14 reduces monofilament scratches through the exit section design (30° chamfer ±0.5mm smooth transition) of the fourth mold 33 (hole diameter 2.35±0.015mm).

[0058] All layers are twisted in the left direction. Figure 4 This is a schematic diagram of layered stranding. After each layer is stranded, it is guided and aligned by a polycrystalline diamond mold system with integrated intelligent sensors and a bearing block, which monitors the tension of each single filament in real time; it has closed-loop feedback adjustment capability, and dynamically adjusts the output of the servo motor through a PID algorithm to ensure that the tension fluctuation is ≤3%.

[0059] Performance testing The test results are shown in Table 2. Detection method: 1. Cable roundness inspection: Refer to GB / T2951.11-2008 "General test methods for insulation and sheath materials of cables and optical fibers - Part 11: General test methods for thickness and dimensional measurement" and the dimensional measurement methods of the equivalent IEC 60811-203 series standards for inspection; 2. Wire breakage rate test: The test shall be conducted in accordance with the IEC60228 / GB / T5023 series of test methods for the integrity of conductor structure.

[0060] Table 2. Cable roundness deviation and wire breakage rate in Example 2

[0061] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A copper-clad aluminum conductor, characterized in that, It includes an aluminum core, a transition metal layer, and a copper cladding layer arranged sequentially from the inside out.

2. The copper-clad aluminum conductor as described in claim 1, characterized in that, The transition metal layer is plated on the inner side of the copper cladding layer and welded to the aluminum core.

3. The copper-clad aluminum conductor as described in claim 2, characterized in that, The alloy transition layer includes a Sn-Mg alloy transition layer.

4. The method for preparing copper-clad aluminum conductors as described in any one of claims 1 to 3, characterized in that, Includes the following steps: S1. A transition metal layer is plated on one side of the copper strip to form a composite copper strip; S2. The side of the composite copper strip with the transition metal layer is wrapped around the outer surface of the preheated aluminum core. The transition metal layer is introduced into the copper-aluminum interface by composite rolling and diffusion welding. After rapid cooling, the copper-clad aluminum conductor is annealed in a protective atmosphere to form the copper-clad aluminum conductor.

5. The method for preparing copper-clad aluminum conductor as described in claim 4, characterized in that, In step S1, the plating method is electroplating.

6. The method for preparing copper-clad aluminum conductor as described in claim 4, characterized in that, In step S1, the temperature of the preheated aluminum core is 240~260°C.

7. The method for preparing copper-clad aluminum conductor as described in claim 4, characterized in that, In step S1, the welding temperature is 380~420°C and the time is 8~12 minutes.

8. The method for preparing copper-clad aluminum conductor as described in claim 4, characterized in that, In step S2, the annealing process specifically involves heating from room temperature to 280-320°C at a heating rate of 4-6°C / min, holding at that temperature for 15-25 minutes, and then cooling it in the furnace.

9. A cable, characterized in that, The cable is made of multiple copper-clad aluminum conductors twisted together in the same direction.

10. The cable as described in claim 9, characterized in that, It includes an intermediate layer and multiple outer layers, wherein the intermediate layer includes a copper-clad aluminum conductor, and each of the outer layers includes multiple copper-clad aluminum conductors.

11. A method for manufacturing a cable, characterized in that, Includes the following steps: S10. Provide a plurality of copper-clad aluminum conductors as described in any one of claims 1 to 3, wherein the plurality of copper-clad aluminum conductors include a central copper-clad aluminum conductor and a peripheral copper-clad aluminum conductor, wherein the diameter of the central copper-clad aluminum conductor is larger than that of the peripheral copper-clad aluminum conductor. S20. Position the center copper-clad aluminum wire through the first mold on the first wire distribution plate; S30. Multiple peripheral copper-clad aluminum conductors are arranged around the periphery of the central copper-clad aluminum conductor, and at least one outer layer is formed by twisting them in the same direction.

12. The cable as claimed in claim 11, characterized in that, The process of forming at least one outer layer by winding multiple peripheral copper-clad aluminum conductors around the central copper-clad aluminum conductor in the same direction specifically includes: guiding multiple peripheral copper-clad aluminum conductors through a mold and a wire divider, distributing them circumferentially around the central copper-clad aluminum conductor by controlling the twisting angle and pitch ratio, adjusting the tension of the copper-clad aluminum conductors by combining tension feedback, and winding them in the same direction to form at least one outer layer.

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