Aluminum alloy cable and method of making the same

Abstract

The application relates to an aluminum alloy cable and a preparation method thereof, the aluminum alloy cable comprises, from inside to outside, an aluminum alloy conductor pipe, an insulation layer, a shielding layer and an outer protective layer which are sequentially arranged; the material of the aluminum alloy conductor pipe comprises aluminum, a rare earth metal, iron, copper and magnesium; the aluminum alloy conductor pipe comprises the rare earth metal 0.1-0.5%, the iron 0.5-1.8%, the copper 0.15-0.3% and the magnesium 0.01-0.05% according to 100% of the mass fraction of the aluminum alloy conductor pipe. The application limits the material of the aluminum alloy conductor pipe in the aluminum alloy cable, and specifically limits the mass fraction of each material in the aluminum alloy conductor pipe, so that the mechanical strength of the aluminum alloy cable is improved, and the fatigue resistance and the service life under the vibration working condition of the aluminum alloy cable are improved.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, and in particular to an aluminum alloy cable and its preparation method. Background Technology

[0002] With the increasing popularity of lightweight new energy vehicles, aluminum cables are being used more and more in these vehicles. However, due to the inherent characteristics of aluminum conductors, they are prone to breakage and failure under prolonged vibration. Meanwhile, for the silicone rubber insulation layer, there are vulcanization systems such as double 24, double 25, and platinum. Double 24 vulcanization has a fast vulcanization speed at low temperatures, but it produces byproducts and an acidic odor. Double 25 vulcanization is slow and inefficient. Platinum vulcanization can achieve rapid vulcanization and odorless operation, but it has high requirements for the working environment and is costly. For the shielding layer, tinned copper wire braided shielding results in a relatively stiff cable. Under vibration, the braided wires break, easily damaging or puncturing the insulation.

[0003] In summary, the materials of aluminum alloy cables need to be improved to enhance their vibration resistance. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an aluminum alloy cable and its preparation method. This invention improves the mechanical strength of the aluminum alloy cable and enhances its fatigue resistance and lifespan under vibration conditions by limiting the material of the aluminum alloy conductor tube in the aluminum alloy cable and specifically limiting the mass fraction of each material in the aluminum alloy conductor tube.

[0005] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides an aluminum alloy cable, which comprises, from the inside out, an aluminum alloy conductor tube, an insulation layer, a shielding layer and an outer sheath arranged sequentially. The materials of the aluminum alloy conductor tube include aluminum, rare earth metals, iron, copper, and magnesium; Based on a mass fraction of 100%, the aluminum alloy conductor tube comprises 0.1-0.5% rare earth metals, 0.5-1.8% iron, 0.15-0.3% copper, and 0.01-0.05% magnesium.

[0006] Compared to copper as the main material for cables, this invention uses aluminum alloy as the main material for cables to achieve lightweighting. Rare earth metals are added to the aluminum alloy conductor tube to improve the strength of the single wire, enhance vibration resistance, and extend the service life. Specifically, this invention limits the amount of rare earth metals added to 0.1~0.5% to prevent excessive rare earth metals from forming coarse rare earth phases and reducing material performance.

[0007] The mass fraction of rare earth metals in the aluminum alloy conductor tube is 0.1% to 0.5%, for example, it can be 0.1%, 0.2%, 0.3%, 0.4% or 0.5%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0008] The mass fraction of iron in the aluminum alloy conductor tube is 0.5% to 1.8%, for example, it can be 0.5%, 0.8%, 1.1%, 1.5% or 1.8%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0009] The mass fraction of copper in the aluminum alloy conductor tube is 0.15~0.3%, for example, it can be 0.15%, 0.2%, 0.25% or 0.3%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0010] The mass fraction of magnesium in the aluminum alloy conductor tube is 0.01~0.05%, for example, it can be 0.01%, 0.02%, 0.03%, 0.04% or 0.05%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0011] As a preferred embodiment of the present invention, the aluminum alloy conductor tube is further made of silicon and manganese.

[0012] Preferably, based on a mass fraction of 100% for the aluminum alloy conductor tube, the aluminum alloy conductor tube comprises 0.3-1.0% silicon and 0.01-0.1% manganese, wherein the mass fraction of silicon is 0.3-1.0%, for example, it can be 0.3%, 0.5%, 0.7%, 0.8% or 1.0%, and the mass fraction of manganese is 0.01-0.1%, for example, it can be 0.01%, 0.02%, 0.04%, 0.06%, 0.08% or 0.1%, but is not limited to the listed values, and other unlisted values ​​within the above range are also applicable.

[0013] Preferably, the aluminum alloy conductor tube is an annealed aluminum alloy stranded conductor formed by regular stranding.

[0014] Preferably, the rare earth metal includes any one or a combination of at least two of La, Ce, Y, Sc or Er, wherein typical but non-limiting combinations include: a combination of La and Ce, a combination of La and Y, a combination of Ce and Y, a combination of Y, Sc and Er, and preferably a combination of La and Ce.

[0015] Preferably, the mass ratio of La to Ce is (1~3):1, for example, it can be 1:1, 1.5:1, 2:1, 2.5:1 or 3:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0016] This invention involves adding rare earth metals to aluminum alloy conductor tubes. Because rare earth metals have a strong affinity for aluminum, their addition effectively removes trace heavy metal impurities present in the aluminum alloy, achieving a good refining effect and further improving the conductivity of the aluminum alloy conductor tube, ensuring its performance. Furthermore, when the added rare earth metal is a combination of La and Ce, with a La to Ce mass ratio of (1~3):1, it has a better effect than adding a single rare earth metal or other combinations of rare earth metals. This is because, compared to single rare earth metals or other rare earth metals, La and Ce have a synergistic effect; La focuses on grain refinement and purification. The matrix (combined with impurities such as S / O); Ce is good at modifying inclusions and promoting dispersed precipitation; composite addition can deeply purify grain boundaries, eliminate low-melting-point eutectics, and make the grains more uniform and dense. The combination of La and Ce can simultaneously optimize strength, toughness, creep resistance and thermal fatigue, thereby improving the performance of aluminum alloy conductor tubes. Furthermore, when the mass ratio of La to Ce is (1~3):1, the synergistic effect of La and Ce can be fully utilized, avoiding the performance degradation caused by an excess of one metal. However, the addition of a single rare earth metal or other rare earth metal combinations can only partially improve strength and creep resistance, and cannot simultaneously optimize strength, toughness, creep resistance and thermal fatigue.

[0017] Preferably, the insulating layer is made of silicone rubber.

[0018] Preferably, the material of the shielding layer includes tin-plated copper wire and aluminum foil.

[0019] Preferably, based on the mass fraction of the tin-plated copper wire being 100%, the tin content in the tin-plated copper wire is 0.5% to 1.5%, for example, it can be 0.5%, 0.7%, 1%, 1.2% or 1.5%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0020] Preferably, the shielding layer comprises tin-plated copper wire and aluminum foil spirally wound in sequence.

[0021] In this invention, the shielding layer has a spiral structure, in which tinned copper wires are wound in a cross spiral to form a mesh-like covering layer outside the insulation layer. The density is generally 80-85%. With the addition of aluminum foil wrapping, a composite shield is formed, with a coverage rate of 100%, thereby improving the lifespan of the cable under vibration conditions.

[0022] Preferably, the material of the outer protective layer includes silicone rubber.

[0023] As a preferred technical solution of the present invention, the diameter of the aluminum alloy conductor tube is 0.3~0.5mm, for example, it can be 0.3mm, 0.35mm, 0.4mm, 0.45mm or 0.5mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0024] The aluminum alloy conductor tube of the present invention comprises a conductor tube formed by twisting and pressing at least 19 annealed aluminum alloy monofilaments, and the arrangement of the aluminum alloy monofilaments in the aluminum alloy conductor tube includes 1+6+12, that is, the outer surface of the central aluminum alloy monofilament in the aluminum alloy conductor tube is provided with 6 aluminum alloy monofilaments, and the outer surface of the 6 aluminum alloy monofilaments is provided with 12 aluminum alloy monofilaments.

[0025] Preferably, the thickness of the insulating layer is 0.5~1mm, for example, it can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0026] Preferably, the thickness of the shielding layer is 0.1~0.2mm, for example, it can be 0.1mm, 0.12mm, 0.15mm, 0.18mm or 0.2mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0027] Preferably, the thickness of the outer protective layer is 0.8~1.6mm, for example, it can be 0.8mm, 1mm, 1.2mm, 1.4mm or 1.6mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0028] In a second aspect, the present invention provides a method for preparing an aluminum alloy cable according to the first aspect, the method comprising the following steps: (1) Preparation of aluminum alloy conductor tube: molten aluminum ingot and first alloy are mixed in a mass ratio of (97.65~99.5):1 and subjected to a first heat treatment to obtain a first mixture. Then, the first mixture is subjected to a first refining treatment and a second refining treatment to obtain aluminum alloy monofilament. The aluminum alloy monofilament is used to prepare aluminum alloy conductor tube. The first alloy comprises Al-RE master alloy, Fe, Cu, and Mg; the mass ratio of Al-RE master alloy, Fe, Cu, and Mg in the first alloy is (97~99):(5~18):(1.5~3):(0.1~0.5); the mass content of RE in the Al-RE master alloy is 5~10%. (2) The aluminum alloy conductor tube is wrapped with an insulation layer, a shielding layer and a sheath layer in sequence to obtain the aluminum alloy cable.

[0029] This invention uses Al-RE master alloy as raw material to provide rare earth metals. Compared with directly adding pure rare earth metals, the burn loss is small and the prepared aluminum alloy conductor tube has good uniformity. This invention first prepares the aluminum alloy conductor tube, and then sequentially coats the outside of the aluminum alloy conductor tube with an insulation layer, a shielding layer and a sheath layer to obtain an aluminum alloy cable. The preparation method provided by this invention is simple, easy to operate and easy to scale up in industry.

[0030] It should be noted that RE represents rare earth metals.

[0031] In the first mixing process, the mass ratio of molten aluminum ingot to the first alloy is (97.65~99.5):1, for example, it can be 97.65:1, 98:1, 98.5:1, 99:1 or 99.5:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0032] The mass ratio of Al-RE master alloy, Fe, Cu and Mg in the first alloy is (97~99):(5~18):(1.5~3):(0.1~0.5), for example, it can be 97:5:1.5:0.1, 98:10:2:0.3, 98:5:1.5:0.5, 98:18:3:0.1 or 99:18:3:0.5, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0033] The mass content of RE in the Al-RE master alloy is 5-10%, for example, it can be 5%, 6%, 7%, 8%, 9% or 10%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0034] As a preferred technical solution of the present invention, the preparation of the molten aluminum ingot includes: preheating the aluminum ingot to obtain the molten aluminum ingot.

[0035] Preferably, the purity of the aluminum ingot is ≥99.7%, for example, it can be 99.7%, 99.75%, 99.8%, 99.85% or 99.9%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0036] Preferably, the temperature of the preheating treatment is 720~750℃, for example, it can be 720℃, 730℃, 735℃, 740℃ or 750℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0037] The present invention preheats aluminum ingots at 720~750℃ to remove moisture.

[0038] Preferably, the preheating treatment time is 6 to 8 hours, for example, 6 hours, 6.5 hours, 7 hours, 7.5 hours or 8 hours, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0039] Preferably, the first alloy further includes Si and Mn.

[0040] Preferably, the mass ratio of Al-RE master alloy, Si and Mn in the first alloy is (97~99):(3~10):1, for example, it can be 97:3:1, 97:10:1, 98:6:1, 99:3:1 or 99:10:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0041] Preferably, the RE in the Al-RE master alloy includes any one or a combination of at least two of La, Ce, Y, Sc or Er, wherein typical but non-limiting combinations include: a combination of La and Ce, a combination of La and Y, a combination of Ce and Y, a combination of Y, Sc and Er, and preferably a combination of La and Ce.

[0042] Preferably, the mass ratio of La to Ce is (1~3):1, for example, it can be 1:1, 1.5:1, 2:1, 2.5:1 or 3:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0043] Preferably, the temperature of the first heat treatment is 750~800℃, for example, it can be 750℃, 760℃, 770℃, 780℃, 790℃ or 800℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0044] This invention limits the temperature of the first heat treatment to ensure that the prepared aluminum alloy conductor tube has good uniformity. If the temperature is too low, the dissolution will be slow and the reaction efficiency will be low. If the temperature is too high, the burn-off will be too large.

[0045] Preferably, the first heat treatment time is 5 to 10 minutes, for example, it can be 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes or 10 minutes, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0046] Preferably, the first heat treatment is performed under stirring.

[0047] Preferably, the stirring speed is 200~400 r / min, for example, it can be 200 r / min, 250 r / min, 300 r / min, 350 r / min or 400 r / min, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0048] As a preferred technical solution of the present invention, the temperature of the first refining process is 750~800℃, for example, it can be 750℃, 760℃, 770℃, 780℃, 790℃ or 800℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0049] Preferably, the first refining process takes 10 to 20 minutes, for example, 10 minutes, 12 minutes, 15 minutes, 18 minutes or 20 minutes, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0050] Preferably, the first refining agent used in the first refining process includes a chloride-fluoride composite refining agent.

[0051] Preferably, the mass ratio of chloride salt to fluoride salt in the first refining agent is (3~8):1, for example, it can be 3:1, 4:1, 5:1, 6:1, 7:1 or 8:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0052] Preferably, the chloride salt includes NaCl and KCl.

[0053] The present invention specifically defines the chloride salts in the first refining agent as including NaCl and KCl, so as to achieve low melting point eutectic, wet the aluminum liquid, and promote dispersion.

[0054] Preferably, the fluoride salt includes Na3AlF6 and CaF2.

[0055] Specifically, the fluoride salts in the first refining agent include Na3AlF6 and CaF2, so as to destroy the Al2O3 film, adsorb inclusions, and reduce viscosity.

[0056] Preferably, based on a mass fraction of 100% for the chloride-fluoride composite refining agent, the chloride salt comprises 40-50% NaCl and 30-40% KCl, wherein the mass fraction of NaCl is 40-50%, for example, it can be 40%, 42%, 45%, 48% or 50%, and the mass fraction of KCl is 30-40%, for example, it can be 30%, 32%, 35%, 38% or 40%, but is not limited to the listed values, and other unlisted values ​​within the above range are also applicable.

[0057] Preferably, based on a mass fraction of 100% for the chloride-fluoride composite refining agent, the fluoride salt comprises 8-12% Na3AlF6 and 3-5% CaF2, wherein the mass fraction of Na3AlF6 is 8-12%, for example, 8%, 9%, 10%, 11% or 12%, and the mass fraction of CaF2 is 3-5%, for example, 3%, 3.5%, 4%, 4.5% or 5%, but is not limited to the listed values; other unlisted values ​​within the above range are also applicable.

[0058] Preferably, the first refining process is carried out under an argon atmosphere.

[0059] Preferably, the purity of argon gas in the first refining process is ≥99.9%, for example, it can be 99.9%, 99.92%, 99.94%, 99.96% or 99.99%, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0060] Preferably, the temperature of the second refining process is 750~800℃, for example, it can be 750℃, 760℃, 770℃, 780℃, 790℃ or 800℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0061] Preferably, the second refining process takes 10 to 20 minutes, for example, 10 minutes, 12 minutes, 15 minutes, 18 minutes or 20 minutes, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0062] Preferably, the second refining agent used in the second refining process includes BF3 and C2Cl6.

[0063] Preferably, the mass ratio of BF3 to C2Cl6 in the second refining agent is (1~3):1, for example, it can be 1:1, 1.5:1, 2:1, 2.5:1 or 3:1, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0064] The present invention specifically limits the mass ratio of BF3 and C2Cl6 in the second refining agent to (1~3):1, so as to achieve deep purification.

[0065] Preferably, the first refining process and the second refining process are each performed independently in ultrasound.

[0066] This invention employs ultrasound-assisted first and second refining processes to refine the microstructure and homogenize rare earth metals.

[0067] Preferably, the frequency of the ultrasound is 20~25kHz, for example, it can be 20kHz, 21kHz, 22kHz, 23kHz, 24kHz or 25kHz, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0068] Preferably, the power of the ultrasound is 1.5~2.5kW, for example, it can be 1.5kW, 1.7kW, 2kW, 2.2kW or 2.5kW, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0069] As a preferred technical solution of the present invention, the preparation of the aluminum alloy conductor tube includes: sequentially performing regular stranding and annealing treatment on the aluminum alloy monofilament to obtain the aluminum alloy conductor tube.

[0070] Preferably, the stranding pitch in the regular stranding is 10 to 15 times the diameter of the aluminum alloy monofilament, for example, it can be 10, 11, 12, 13, 14 or 15 times, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0071] Preferably, the annealing temperature is 180~220℃, for example, it can be 180℃, 190℃, 200℃, 210℃ or 220℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0072] Preferably, the annealing time is 12 to 14 hours, for example, 12 hours, 12.5 hours, 13 hours, 13.5 hours or 14 hours, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0073] As a preferred technical solution of the present invention, the preparation of the insulating material of the insulating layer includes: mixing the basic raw materials of the insulating material, the 2,4-dimethyl vulcanizing agent, the defrosting agent and the color paste in a second mixing process to obtain a second mixture; performing a kneading treatment on the second mixture to obtain an insulating rubber compound; and performing an extrusion vulcanization molding treatment on the insulating rubber compound to obtain the insulating material.

[0074] Preferably, the mass ratio of the base raw material, bis(2,4) vulcanizing agent, defrosting agent, and color paste in the second mixing process is 100:(1.2~1.5):(0.3~0.5):(0.9~1.0), for example, it can be 100:1.2:0.3:0.9, 100:1.3:0.4:0.95, 100:1.3:0.3:1.0, 100:1.4:0.5:0.9, or 100:1.5:0.5:1.0, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0075] Similarly, the specific selection of defrosting agent and color paste in this invention has almost no impact on the performance of aluminum alloy cables. Those skilled in the art can select the specific grades of the aforementioned substances as needed, without making specific limitations here.

[0076] Preferably, the mixing temperature is 10~25℃, for example, it can be 10℃, 12℃, 15℃, 20℃ or 25℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0077] Preferably, the mixing time is 8 to 10 minutes, for example, 8 minutes, 8.5 minutes, 9 minutes, 9.5 minutes or 10 minutes, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0078] Preferably, the preparation of the basic raw material includes: a third mixing of methyl vinyl silicone rubber, fumed silica, structure control agent, odor absorber, halogen-free flame retardant synergist, antioxidant, passivator and silane coupling agent to obtain a third mixture, and then subjecting the third mixture to intensive mixing to obtain the basic raw material.

[0079] It should be noted that the odor-absorbing aid in this invention can both absorb odors and remove acid.

[0080] This invention retains the advantages of low cost and high efficiency of 2,4-dimethylsiloxane, and adds odor-absorbing agents and defrosting agents during the preparation of insulating materials to reduce the odor of silicone, achieving an odor level of ≤3.5, meeting the requirements for use in new energy vehicles, and improving the customer experience.

[0081] Preferably, in the third mixing process, the mass ratio of methyl vinyl silicone rubber, fumed silica, structure control agent, odor absorbent, halogen-free flame retardant synergist, antioxidant, passivator, and silane coupling agent is (50~80):(10~40):(0.1~10):(0.1~10):(1~6):(2~5):(1~3):1, for example, it can be 50:10:0.1:0.1:1:2:1:1, 60:25:5:5:3:3:2:1, 60:10:10:5:3:2:3:1, 60:40:5:5:1:5:1:1 or 80:40:10:10:6:5:3:1, but it is not limited to the listed values, and other unlisted values ​​within the above range are also applicable.

[0082] In this invention, the specific selection of structure control agent, odor absorber, halogen-free flame retardant synergist, antioxidant, passivator and silane coupling agent has almost no impact on the performance of aluminum alloy cable. Those skilled in the art can select the specific grades of the aforementioned substances as needed, and no specific limitation is made here.

[0083] Preferably, the temperature of the mixing process is <100°C, for example, it can be 80°C, 85°C, 90°C or 95°C, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0084] Preferably, the mixing time is 10 to 20 minutes, for example, 10 minutes, 12 minutes, 15 minutes, 18 minutes or 20 minutes, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0085] As a preferred technical solution of the present invention, the extrusion vulcanization molding process includes an eight-stage extrusion vulcanization process.

[0086] Preferably, the extrusion vulcanization process includes a first extrusion vulcanization process, a second extrusion vulcanization process, a third extrusion vulcanization process, a fourth extrusion vulcanization process, a fifth extrusion vulcanization process, a sixth extrusion vulcanization process, a seventh extrusion vulcanization process, and an eighth extrusion vulcanization process performed sequentially.

[0087] Preferably, the extrusion temperature of the first extrusion vulcanization treatment is 750~850℃, for example, it can be 750℃, 780℃, 800℃, 820℃ or 850℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0088] Preferably, the extrusion temperature of the second extrusion vulcanization treatment is 650~740℃, for example, it can be 650℃, 680℃, 700℃, 720℃ or 740℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0089] Preferably, the extrusion temperature of the third extrusion vulcanization treatment is 550~640℃, for example, it can be 550℃, 580℃, 600℃, 620℃ or 640℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0090] Preferably, the extrusion temperatures of the fourth, fifth, and sixth extrusion vulcanization processes are each independently 150~250℃, for example, 150℃, 180℃, 200℃, 220℃, or 250℃, but are not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0091] Preferably, the extrusion temperature of the seventh extrusion vulcanization process and the eighth extrusion vulcanization process is independently 350~450℃, for example, it can be 350℃, 380℃, 400℃, 420℃ or 450℃, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0092] In the extrusion vulcanization process of this invention, the first three sections undergo high-temperature extrusion for rapid vulcanization and shaping, while the last five sections are kept at a low temperature to ensure thorough vulcanization. Simultaneously, this invention adjusts the vulcanization process, increasing the temperature of the last two vulcanization chambers from 150-250°C to 350-450°C to accelerate the volatilization of acidic gases generated during vulcanization and reduce the need for secondary processing or prolonged air circulation to dissipate odors.

[0093] As a preferred technical solution of the present invention, the preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with forward and reverse spirals, one layer spiraling left and the other spiraling right; and then winding aluminum foil around the outside of the tin-plated copper wire.

[0094] Preferably, the tin-plated copper wire is wound at an angle of 50 to 65°, for example, 50°, 55°, 60° or 65°, but is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0095] In this invention, tin-plated copper wire is wound at a specific angle and in a specific manner to form a two-layer structure with opposing spirals: one layer spiraling to the left and the other to the right. This is key to structural balance, effectively counteracting the spin tendency of the cable under stress, preventing structural loosening, and creating a spring effect: when the cable bends, the oblique winding layer can stretch and slide like a spring, thereby evenly distributing bending stress to each conductor and significantly reducing internal friction. Furthermore, unlike braided structures (crosspoint locking), the parallel conductor layers of the oblique winding structure allow for relative displacement, which can more effectively release the accumulated stress generated by bending and torsion, resulting in stronger vibration resistance.

[0096] Preferably, the thickness of the left-handed structural layer is 0.11~0.2mm, for example, it can be 0.11mm, 0.12mm, 0.14mm, 0.17mm or 0.2mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0097] Preferably, the thickness of the right-handed structural layer is 0.11~0.2mm, for example, it can be 0.11mm, 0.12mm, 0.14mm, 0.17mm or 0.2mm, but it is not limited to the listed values. Other unlisted values ​​within the above range are also applicable.

[0098] Preferably, the material of the sheath layer includes silicone rubber.

[0099] Preferably, the preparation method includes the following steps: (1) Preparation of aluminum alloy monofilament: Aluminum ingots with a purity ≥99.7% are preheated at 720~750℃ for 6~8h to obtain molten aluminum ingots; the molten aluminum ingots and the first alloy are mixed at a mass ratio of (97.65~99.5):1, and subjected to a first heat treatment at 750~800℃ for 5~10min at a rotation speed of 200~400r / min to obtain a first mixture; then the first mixture is subjected to ultrasonic treatment at a frequency of 20~25kHz and a power of 1.5~2.5kW at a temperature of 750~800℃. A first refining process lasting 10-20 minutes and a second refining process lasting 10-20 minutes at 750-800℃ are used to obtain aluminum alloy monofilaments. The first refining process is carried out in an atmosphere with argon purity ≥99.9%. The first refining agent, with a mass fraction of 100%, comprises 40-50% NaCl, 30-40% KCl, 8-12% Na3AlF6, and 3-5% CaF2. The second refining agent used in the second refining process is BF3 and C2Cl6 in a mass ratio of (1-3):1. The first alloy comprises an Al-RE master alloy in a mass ratio of (97~99):(5~18):(3~10):(1.5~3):(0.1~0.5):1, Fe, Si, Cu, Mg, and Mn; the mass content of RE in the Al-RE master alloy is 5~10%; the RE in the Al-RE master alloy comprises any one or a combination of at least two of La, Ce, Y, Sc, or Er. (2) Preparation of aluminum alloy conductor tube: The aluminum alloy monofilament is subjected to regular stranding and annealing treatment at a temperature of 180~220℃ for 12~14h in sequence to obtain aluminum alloy conductor tube; wherein, the stranding pitch in the regular stranding is 10~15 times the diameter of the aluminum alloy monofilament. (3) An insulating layer is wrapped around the outside of the aluminum alloy conductor tube; the preparation of the insulating material of the insulating layer includes: mixing methyl vinyl silicone rubber, fumed silica, structure control agent, odor absorber, halogen-free flame retardant synergist, antioxidant, passivator and silane coupling agent in a mass ratio of (50~80):(10~40):(0.1~10):(0.1~10):(1~6):(2~5):(1~3):1 to obtain a third mixture, and subjecting the third mixture to a intensive mixing process at a temperature <100℃ for 10~20min to obtain the basic raw material; The base raw materials, bis(2,4) vulcanizing agent, defrosting agent, and color paste are mixed in a mass ratio of 100:(1.2~1.5):(0.3~0.5):(0.9~1.0) to obtain a second mixture. The second mixture is then kneaded at a temperature of 10~25℃ for 8~10 minutes to obtain an insulating compound. The insulating compound is then extruded and vulcanized to obtain an insulating material. The extrusion vulcanization molding process includes, in sequence, a first extrusion vulcanization process at an extrusion temperature of 750~850℃, a second extrusion vulcanization process at an extrusion temperature of 650~740℃, a third extrusion vulcanization process at an extrusion temperature of 550~640℃, a fourth extrusion vulcanization process at an extrusion temperature of 150~250℃, a fifth extrusion vulcanization process at an extrusion temperature of 150~250℃, a sixth extrusion vulcanization process at an extrusion temperature of 150~250℃, a seventh extrusion vulcanization process at an extrusion temperature of 350~450℃, and an eighth extrusion vulcanization process at an extrusion temperature of 350~450℃. (4) A shielding layer and a sheath layer are sequentially wrapped around the outside of the insulation layer to obtain the aluminum alloy cable; The preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with opposite spirals, one layer spiraling left and the other right; then winding aluminum foil around the outside of the tin-plated copper wire; the winding angle of the tin-plated copper wire is 50~65°; the thickness of the left-spiral structure layer is 0.11~0.2mm; the thickness of the right-spiral structure layer is 0.11~0.2mm.

[0100] Compared with the prior art, the present invention has at least the following beneficial effects: In this invention, aluminum alloy is used as the main material for the cable to achieve lightweighting. Rare earth metals with a mass fraction of 0.1~0.5% are added to the aluminum alloy conductor tube, and the rare earth metals are provided by Al-RE master alloy as raw material. This results in good uniformity of the prepared aluminum alloy conductor tube, which improves the strength of the single wire, enhances the vibration resistance, and extends the service life. Specifically, the tensile strength of the aluminum alloy cable can reach more than 145MPa, and the elongation at break can reach more than 22%. Attached Figure Description

[0101] Figure 1 This is a schematic diagram of the structure of the aluminum alloy cable provided in Embodiment 1 of the present invention.

[0102] Among them, 1-aluminum alloy conductor tube; 2-insulation layer; 3-shielding layer; 4-outer protective layer. Detailed Implementation

[0103] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0104] Example 1 This embodiment provides an aluminum alloy cable, such as Figure 1 As shown, the aluminum alloy cable includes, from the inside out, an aluminum alloy conductor tube 1, an insulation layer 2, a shielding layer 3, and an outer sheath 4 arranged sequentially. Based on a mass fraction of 100%, the aluminum alloy conductor tube 1 comprises 0.3% rare earth metals, 1% iron, 0.6% silicon, 0.2% copper, 0.03% magnesium, and 0.05% manganese, with the balance being aluminum; wherein the rare earth metals are La and Ce in a mass ratio of 2:1. The aluminum alloy conductor tube 1 is an annealed aluminum alloy stranded conductor formed by regular stranding; the diameter of the aluminum alloy conductor tube 1 is 0.4 mm; the material of the insulation layer 2 is silicone rubber; the thickness of the insulation layer 2 is 0.8 mm; the shielding layer 3 includes tin-plated copper wire and aluminum foil spirally wound in sequence; based on the mass fraction of the tin-plated copper wire being 100%, the tin content in the tin-plated copper wire is 1%; the thickness of the shielding layer 3 is 0.15 mm; the material of the outer sheath 4 is silicone rubber; the thickness of the outer sheath 4 is 1.2 mm.

[0105] This embodiment also provides a method for preparing the aluminum alloy cable, the method comprising the following steps: (1) Preparation of aluminum alloy monofilament: Aluminum ingots with a purity of 99.8% were preheated at 735℃ for 7 hours to obtain molten aluminum ingots; the molten aluminum ingots and the first alloy were mixed at a mass ratio of 98.5:1 and subjected to a first heat treatment at 780℃ for 8 minutes at a rotation speed of 300 r / min to obtain a first mixture; then the first mixture was subjected to an ultrasonic treatment at 780℃ for 15 minutes at a frequency of 22 kHz and a power of 2 kW. The process involves a first refining treatment at 780°C and a second refining treatment at 15 minutes to obtain aluminum alloy monofilaments. The first refining treatment is conducted in an atmosphere of 99.95% argon purity. The first refining agent, with a mass fraction of 100%, comprises 48% NaCl, 38% KCl, 10% Na3AlF6, and 4% CaF2. The second refining agent used in the second refining treatment is BF3 and C2Cl6 in a mass ratio of 2:1. The first alloy comprises an Al-RE master alloy in a mass ratio of 98:12:6:2:0.3:1, Fe, Si, Cu, Mg, and Mn; the mass content of RE in the Al-RE master alloy is 8%; the RE in the Al-RE master alloy is La and Ce in a mass ratio of 2:1. (2) Preparation of aluminum alloy conductor tube: The aluminum alloy monofilament is subjected to regular stranding and annealing treatment at 200℃ for 13h in sequence to obtain aluminum alloy conductor tube; wherein, the arrangement of aluminum alloy monofilament in the regular stranding is 1+6+12; the stranding pitch in the regular stranding is 13 times the diameter of aluminum alloy monofilament. (3) An insulating layer is wrapped around the outside of the aluminum alloy conductor tube; the preparation of the insulating material of the insulating layer includes: a third mixture of p-methyl vinyl silicone rubber, fumed silica, structure control agent (diphenylsilanediol), odor-absorbing agent (inorganic silicate, brand name JH-801), halogen-free flame retardant synergist (bisphenol A bis-diphenyl phosphate), antioxidant (phosphite antioxidant, brand name 168), passivating agent (N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine) and silane coupling agent (brand name KH-550) to obtain a third mixture, and the third mixture is subjected to a intensive mixing treatment at a temperature of 90°C for 15 minutes to obtain the basic raw material; The base raw materials, 2,4-dimethyl vulcanizing agent, defrosting agent (brand name TF-02), and color paste were mixed in a mass ratio of 100:1.3:0.4:0.95 to obtain a second mixture. The second mixture was then subjected to a kneading treatment at a temperature of 15°C for 9 minutes to obtain an insulating compound. The insulating compound was then subjected to extrusion vulcanization molding to obtain an insulating material. The extrusion vulcanization molding process includes, in sequence, a first extrusion vulcanization process at an extrusion temperature of 800°C, a second extrusion vulcanization process at an extrusion temperature of 700°C, a third extrusion vulcanization process at an extrusion temperature of 600°C, a fourth extrusion vulcanization process at an extrusion temperature of 200°C, a fifth extrusion vulcanization process at an extrusion temperature of 200°C, a sixth extrusion vulcanization process at an extrusion temperature of 200°C, a seventh extrusion vulcanization process at an extrusion temperature of 400°C, and an eighth extrusion vulcanization process at an extrusion temperature of 400°C. (4) A shielding layer and a sheath layer are sequentially wrapped around the outside of the insulation layer to obtain the aluminum alloy cable; The preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with opposite spirals, one layer spiraling left and the other right; then winding aluminum foil around the outside of the tin-plated copper wire; the winding angle of the tin-plated copper wire is 60°; the thickness of the left-spiral structure layer is 0.15 mm; and the thickness of the right-spiral structure layer is 0.15 mm.

[0106] Example 2 This embodiment provides an aluminum alloy cable, which includes, from the inside out, an aluminum alloy conductor tube, an insulation layer, a shielding layer, and an outer sheath arranged sequentially. Based on a mass fraction of 100%, the aluminum alloy conductor tube comprises 0.5% rare earth metals, 0.5% iron, 1.0% silicon, 0.3% copper, 0.01% magnesium, and 0.01% manganese, with the balance being aluminum; wherein the rare earth metals are Ce, Y, and Sc in a mass ratio of 2:1:1. The aluminum alloy conductor tube is an annealed aluminum alloy stranded conductor formed by regular stranding; the diameter of the aluminum alloy conductor tube is 0.5 mm; the material of the insulation layer is silicone rubber; the thickness of the insulation layer is 1 mm; the shielding layer includes tin-plated copper wire and aluminum foil spirally wound in sequence; based on the mass fraction of the tin-plated copper wire being 100%, the tin content in the tin-plated copper wire is 0.5%; the thickness of the shielding layer is 0.2 mm; the material of the outer sheath is silicone rubber; the thickness of the outer sheath is 1.6 mm.

[0107] This embodiment also provides a method for preparing the aluminum alloy cable, the method comprising the following steps: (1) Preparation of aluminum alloy monofilament: Aluminum ingots with a purity of 99.7% were preheated at 750℃ for 6 hours to obtain molten aluminum ingots; the molten aluminum ingots and the first alloy were mixed at a mass ratio of 97.65:1, and subjected to a first heat treatment at 800℃ for 5 minutes at a rotation speed of 200 r / min to obtain a first mixture; then the first mixture was subjected to an ultrasonic treatment at a frequency of 25 kHz and a power of 2.5 kW for 20 minutes at a temperature of 750℃. A first refining process of 10 min and a second refining process of 800℃ for 10 min yield aluminum alloy monofilaments. The first refining process is carried out in an atmosphere of 99.9% argon purity. The first refining agent, with a mass fraction of 100%, comprises 50% NaCl, 35% KCl, 12% Na3AlF6, and 3% CaF2. The second refining agent used in the second refining process is BF3 and C2Cl6 in a mass ratio of 1:1. The first alloy comprises an Al-RE master alloy in a mass ratio of 97:5:10:3:0.1:1, Fe, Si, Cu, Mg, and Mn; the mass content of RE in the Al-RE master alloy is 10%; the RE in the Al-RE master alloy is Ce, Y, and Sc in a mass ratio of 2:1:1. (2) Preparation of aluminum alloy conductor tube: The aluminum alloy monofilament is subjected to regular stranding and annealing treatment at 180°C for 14 hours to obtain aluminum alloy conductor tube; wherein, the arrangement of aluminum alloy monofilament in the regular stranding is 1+6+12; the stranding pitch in the regular stranding is 10 times the diameter of aluminum alloy monofilament. (3) An insulating layer is wrapped around the outside of the aluminum alloy conductor tube; the preparation of the insulating material of the insulating layer includes: a third mixture of p-methyl vinyl silicone rubber, fumed silica, structure control agent (diphenylsilanediol), odor-absorbing agent (inorganic silicate, brand name JH-801), halogen-free flame retardant synergist (bisphenol A bis-diphenyl phosphate), antioxidant (phosphite antioxidant, brand name 168), passivating agent (N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine) and silane coupling agent (brand name KH-550) to obtain a third mixture, and the third mixture is subjected to a intensive mixing treatment at a temperature of 80°C for 20 minutes to obtain the basic raw material; The base raw materials, 2,4-dimethyl vulcanizing agent, defrosting agent (brand name TF-02), and color paste were mixed in a mass ratio of 100:1.2:0.5:0.9 to obtain a second mixture. The second mixture was then subjected to a kneading treatment at a temperature of 25°C for 8 minutes to obtain an insulating compound. The insulating compound was then subjected to extrusion vulcanization molding to obtain an insulating material. The extrusion vulcanization molding process includes, in sequence, a first extrusion vulcanization process at an extrusion temperature of 750°C, a second extrusion vulcanization process at an extrusion temperature of 650°C, a third extrusion vulcanization process at an extrusion temperature of 550°C, a fourth extrusion vulcanization process at an extrusion temperature of 250°C, a fifth extrusion vulcanization process at an extrusion temperature of 250°C, a sixth extrusion vulcanization process at an extrusion temperature of 250°C, a seventh extrusion vulcanization process at an extrusion temperature of 350°C, and an eighth extrusion vulcanization process at an extrusion temperature of 350°C. (4) A shielding layer and a sheath layer are sequentially wrapped around the outside of the insulation layer to obtain the aluminum alloy cable; The preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with opposite spirals, one layer spiraling left and the other right; then winding aluminum foil around the outside of the tin-plated copper wire; the winding angle of the tin-plated copper wire is 50°; the thickness of the left-spiral structure layer is 0.2 mm; and the thickness of the right-spiral structure layer is 0.2 mm.

[0108] Example 3 This embodiment provides an aluminum alloy cable, which includes, from the inside out, an aluminum alloy conductor tube, an insulation layer, a shielding layer, and an outer sheath arranged sequentially. Based on a mass fraction of 100%, the aluminum alloy conductor tube comprises 0.1% rare earth metals, 1.8% iron, 0.3% silicon, 0.15% copper, 0.05% magnesium, and 0.1% manganese, with the balance being aluminum; wherein the rare earth metals are Sc and Er in a mass ratio of 1:1. The aluminum alloy conductor tube is an annealed aluminum alloy stranded conductor formed by regular stranding; the diameter of the aluminum alloy conductor tube is 0.3 mm; the material of the insulation layer is silicone rubber; the thickness of the insulation layer is 0.5 mm; the shielding layer includes tin-plated copper wire and aluminum foil spirally wound in sequence; based on the mass fraction of the tin-plated copper wire being 100%, the tin content in the tin-plated copper wire is 1.5%; the thickness of the shielding layer is 0.1 mm; the material of the outer sheath is silicone rubber; the thickness of the outer sheath is 0.8 mm.

[0109] This embodiment also provides a method for preparing the aluminum alloy cable, the method comprising the following steps: (1) Preparation of aluminum alloy monofilament: Aluminum ingots with a purity of 99.9% were preheated at 720℃ for 8 hours to obtain molten aluminum ingots; the molten aluminum ingots and the first alloy were mixed at a mass ratio of 99.5:1, and subjected to a first heat treatment at 750℃ for 10 minutes at a rotation speed of 400 r / min to obtain a first mixture; then the first mixture was subjected to an ultrasonic treatment at 800℃ for 10 minutes at a frequency of 20 kHz and a power of 1.5 kW. A first refining process of 1 minute and a second refining process of 750℃ for 20 minutes are used to obtain aluminum alloy monofilaments. The first refining process is carried out in an atmosphere with an argon purity of 99.99%. The first refining agent used in the first refining process, with a mass fraction of 100%, includes 47% NaCl, 40% KCl, 8% Na3AlF6, and 5% CaF2. The second refining agent used in the second refining process is BF3 and C2Cl6 in a mass ratio of 3:1. The first alloy comprises an Al-RE master alloy in a mass ratio of 99:18:3:1.5:0.5:1, Fe, Si, Cu, Mg, and Mn; the mass content of RE in the Al-RE master alloy is 5%; the RE in the Al-RE master alloy is Sc and Er in a mass ratio of 1:1. (2) Preparation of aluminum alloy conductor tube: The aluminum alloy monofilament is subjected to regular stranding and annealing treatment at 220°C for 12 hours to obtain aluminum alloy conductor tube; wherein, the arrangement of aluminum alloy monofilament in the regular stranding is 1+6+12; the stranding pitch in the regular stranding is 15 times the diameter of aluminum alloy monofilament. (3) An insulating layer is wrapped around the outside of the aluminum alloy conductor tube; the preparation of the insulating material of the insulating layer includes: a third mixture of p-methyl vinyl silicone rubber, fumed silica, structure control agent (diphenylsilanediol), odor-absorbing agent (inorganic silicate, brand name JH-801), halogen-free flame retardant synergist (bisphenol A bis-diphenyl phosphate), antioxidant (phosphite antioxidant, brand name 168), passivating agent (N,N'-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine) and silane coupling agent (brand name KH-550) to obtain a third mixture, and the third mixture is subjected to a intensive mixing treatment at a temperature of 95°C for 10 minutes to obtain the basic raw material; The base raw materials, 2,4-dimethyl vulcanizing agent, defrosting agent (brand name TF-02), and color paste are mixed in a mass ratio of 100:1.5:0.3:1.0 to obtain a second mixture. The second mixture is then kneaded at 10°C for 10 minutes to obtain an insulating compound. The insulating compound is then extruded and vulcanized to obtain an insulating material. The extrusion vulcanization molding process includes, in sequence, a first extrusion vulcanization process at an extrusion temperature of 850°C, a second extrusion vulcanization process at an extrusion temperature of 740°C, a third extrusion vulcanization process at an extrusion temperature of 640°C, a fourth extrusion vulcanization process at an extrusion temperature of 150°C, a fifth extrusion vulcanization process at an extrusion temperature of 150°C, a sixth extrusion vulcanization process at an extrusion temperature of 150°C, a seventh extrusion vulcanization process at an extrusion temperature of 450°C, and an eighth extrusion vulcanization process at an extrusion temperature of 450°C. (4) A shielding layer and a sheath layer are sequentially wrapped around the outside of the insulation layer to obtain the aluminum alloy cable; The preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with opposite spirals, one layer spiraling left and the other right; then winding aluminum foil around the outside of the tin-plated copper wire; the winding angle of the tin-plated copper wire is 65°; the thickness of the left-spiral structure layer is 0.11 mm; and the thickness of the right-spiral structure layer is 0.11 mm.

[0110] Example 4 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the temperature of the first heat treatment is adjusted from 780°C to 700°C, while all other aspects are the same as in Embodiment 1.

[0111] Example 5 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the temperature of the first heat treatment is adjusted from 780°C to 850°C, while all other aspects are the same as in Embodiment 1.

[0112] Example 6 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the mass ratio of La to Ce in the aluminum alloy conductor tube is adjusted from 2:1 to 0.5:1, while all other aspects are the same as in Embodiment 1.

[0113] Example 7 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the mass ratio of La to Ce in the aluminum alloy conductor tube is adjusted from 2:1 to 4:1, while all other aspects are the same as in Embodiment 1.

[0114] Example 8 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the first refining process and the second refining process are not performed in ultrasound, while the rest are the same as Embodiment 1.

[0115] Example 9 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the extrusion vulcanization molding process does not include the eighth extrusion vulcanization process, but all other aspects are the same as in Embodiment 1.

[0116] Example 10 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the temperature of the seventh extrusion vulcanization treatment is adjusted from 400°C to 200°C, while the rest is the same as Embodiment 1.

[0117] Example 11 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the temperature of the eighth extrusion vulcanization treatment is adjusted from 400°C to 200°C, while all other aspects are the same as in Embodiment 1.

[0118] Example 12 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that, except that the shielding layer includes sequentially braided tin-plated copper wire and aluminum foil, everything else is the same as in Embodiment 1.

[0119] Example 13 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that the third mixture does not include an odor-absorbing agent, and its reduction is distributed to the other components of the third mixture according to the mass ratio. Otherwise, it is the same as Embodiment 1.

[0120] Example 14 This embodiment provides an aluminum alloy cable, which differs from Embodiment 1 only in that, except that the second mixture does not include defrosting agent, and its reduction is distributed to the other components of the second mixture by mass ratio, the rest is the same as Embodiment 1.

[0121] Comparative Example 1 This comparative example provides an aluminum alloy cable, which differs from Example 1 only in that the mass fraction of rare earth metals in the aluminum alloy conductor tube is adjusted from 0.3% to 0.05%, that is, the mass ratio of Al-RE master alloy, Fe, Si, Cu, Mg and Mn in the first alloy in the preparation method is adjusted from 98:12:6:2:0.3:1 to 97.5:12:6:2:0.3:1. Otherwise, it is the same as Example 1.

[0122] Comparative Example 2 This comparative example provides an aluminum alloy cable, which differs from Example 1 only in that the mass fraction of rare earth metals in the aluminum alloy conductor tube is adjusted from 0.3% to 1%, that is, the mass ratio of Al-RE master alloy, Fe, Si, Cu, Mg and Mn in the first alloy in the preparation method is adjusted from 98:12:6:2:0.3:1 to 99:12:6:2:0.3:1. Otherwise, it is the same as Example 1.

[0123] Comparative Example 3 This comparative example provides an aluminum alloy cable, which differs from Example 1 only in that the first alloy in step (1) is adjusted to have a mass ratio of Al, RE, Fe, Si, Cu, Mg and Mn of 93:5:12:6:2:0.3:1. All other aspects are the same as in Example 1.

[0124] The room temperature mechanical properties of the aluminum alloy cables in the above embodiments and comparative examples were tested at 25°C using the metal tensile test. The odor level of the aluminum alloy cables was also tested using the qualitative odor method (smelling with the nose). Specifically, 10 trained evaluators were selected to evaluate the odor of the aluminum alloy cables according to the evaluation criteria in Table 1 and score them. The average score of all evaluators was taken to obtain the odor level. The vibration resistance of the aluminum alloy cables was tested according to GB / T2423.10 at a frequency of 100Hz and an acceleration of 2g. The tests were conducted for 72 hours in each of the X, Y, and Z directions. After the tests, it was observed whether the aluminum alloy cables broke. The test results are shown in Table 2.

[0125] Table 1 Table 2 The test results show that: (1) As can be seen from Examples 1 to 3, aluminum alloy is used as the main material of the cable in this invention to achieve lightweighting. Rare earth metals with a mass fraction of 0.1~0.5% are added to the aluminum alloy conductor tube, and rare earth metals are provided by Al-RE intermediate alloy as raw material. This makes the prepared aluminum alloy conductor tube have good uniformity, thereby improving the strength of the single wire, enhancing the vibration resistance, and extending the service life. Specifically, the tensile strength of the aluminum alloy cable can reach more than 145MPa and the elongation at break can reach more than 22%.

[0126] (2) As can be seen from Examples 1 and 4-5, the temperature of the first heat treatment in Example 1 is 780℃, and the tensile strength of the aluminum alloy cable prepared is 155MPa, the elongation at break is 25%, and the conductor does not break after the vibration test; while the temperature of the first heat treatment in Example 4 is 700℃, and the tensile strength of the aluminum alloy cable prepared is 140MPa, the elongation at break is 22%, and the conductor breaks after the vibration test; the temperature of the first heat treatment in Example 5 is 850℃, and the tensile strength of the aluminum alloy cable prepared is 137MPa, the elongation at break is 20%, and the conductor breaks after the vibration test. It can be seen that the present invention limits the temperature of the first heat treatment to make the prepared aluminum alloy conductor tube have good uniformity, thereby improving the strength of the single wire and enhancing the vibration resistance.

[0127] (3) As can be seen from Examples 1 and 6-7, in Example 1, the mass ratio of La to Ce in the aluminum alloy conductor tube is 2:1, and the tensile strength of the final aluminum alloy cable is 155MPa, the elongation at break is 25%, and the conductor does not break after vibration test; while in Example 6, the mass ratio of La to Ce in the aluminum alloy conductor tube is 0.5:1, and the tensile strength of the final aluminum alloy cable is 135MPa, the elongation at break is 18%, and the conductor breaks after vibration test; in Example 7, the mass ratio of La to Ce in the aluminum alloy conductor tube is 4:1, and the tensile strength of the final aluminum alloy cable is 137MPa, the elongation at break is 18%, and the conductor breaks after vibration test. This shows that La and Ce have a synergistic effect. The present invention specifically limits the mass ratio of La to Ce to (1~3):1 to give full play to their synergistic effect, while optimizing strength, toughness, creep resistance and thermal fatigue, thereby improving the performance of the aluminum alloy conductor tube.

[0128] (4) As can be seen from Examples 1 and 8, the present invention uses ultrasonic-assisted first and second refining processes to refine the structure and homogenize rare earth metals, thereby ultimately improving the strength and vibration resistance of aluminum alloy cables.

[0129] (5) As can be seen from Examples 1 and 9-11, the present invention performs an eight-stage extrusion vulcanization process. The first three stages are high-temperature extrusion for rapid vulcanization and shaping, while the last five stages are heat preservation at low temperature. At the same time, by adjusting the vulcanization process, the temperature of the last two vulcanization chambers is increased from 150~250℃ to 350~450℃, which can accelerate the volatilization of acidic gases generated by vulcanization and reduce the need for secondary processing or long-term air circulation to dissipate odors.

[0130] (6) As can be seen from Examples 1 and 12, the shielding layer in Example 1 is made by sequentially winding tin-copper wire and aluminum foil on the outside of the insulation layer. The final aluminum alloy cable has a tensile strength of 155 MPa and an elongation at break of 25%, and the conductor does not break after the vibration test. In contrast, the shielding layer in Example 12 is made by sequentially braiding tin-copper wire and aluminum foil on the outside of the insulation layer. The final aluminum alloy cable has a tensile strength of 135 MPa and an elongation at break of 18%, and the conductor breaks after the vibration test. This shows that in this invention, the tin-plated copper wire is wound at a specific angle and in a specific manner, so that the oblique winding layer can stretch and slide like a spring when the cable is bent, thereby distributing the bending stress evenly to each conductor and greatly reducing internal friction. Moreover, compared with the braided structure, the parallel conductor layer of the oblique winding structure allows relative displacement, which can more effectively release the accumulated stress generated by bending and torsion, and has stronger vibration resistance.

[0131] (7) As can be seen from Examples 1 and 13-14, the third mixture in Example 1 contains odor-absorbing agent and defrosting agent, and its odor level is 3.5. The third mixture in Example 13 does not contain odor-absorbing agent, and its odor level is 5. The third mixture in Example 14 does not contain defrosting agent, and its odor level is 5. This shows that the present invention uses 2,4-dichlorohydrin as raw material and adds odor-absorbing agent and defrosting agent during the preparation of insulating material to reduce the odor of silicone and achieve an odor level ≤3.5, which meets the requirements of new energy vehicles and improves the customer experience.

[0132] (8) As can be seen from Example 1 and Comparative Examples 1-3, the present invention adds 0.1-0.5% rare earth metal by mass to the aluminum alloy conductor tube and uses Al-RE intermediate alloy as raw material to provide rare earth metal for the system, so that the prepared aluminum alloy conductor tube has good uniformity, thereby improving the strength of the single wire, enhancing the vibration resistance and extending the service life.

[0133] In summary, this invention uses aluminum alloy as the main material for the cable to achieve lightweighting. Rare earth metals with a mass fraction of 0.1-0.5% are added to the aluminum alloy conductor tube, and the rare earth metals are provided by the Al-RE master alloy as a raw material. This results in good uniformity of the prepared aluminum alloy conductor tube, improving the strength of the single filament, enhancing vibration resistance, and extending service life. Specifically, the tensile strength of the aluminum alloy cable can reach over 145 MPa, and the elongation at break can reach over 22%.

[0134] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. An aluminum alloy cable, characterized in that, The aluminum alloy cable comprises, from the inside out, an aluminum alloy conductor tube, an insulation layer, a shielding layer, and an outer sheath, arranged sequentially. The materials of the aluminum alloy conductor tube include aluminum, rare earth metals, iron, copper, and magnesium; Based on a mass fraction of 100%, the aluminum alloy conductor tube comprises 0.1-0.5% rare earth metals, 0.5-1.8% iron, 0.15-0.3% copper, and 0.01-0.05% magnesium.

2. The aluminum alloy cable according to claim 1, characterized in that, The aluminum alloy conductor tube also contains silicon and manganese. Preferably, based on a mass fraction of 100% for the aluminum alloy conductor tube, the aluminum alloy conductor tube comprises 0.3-1.0% silicon and 0.01-0.1% manganese; Preferably, the aluminum alloy conductor tube is an annealed aluminum alloy stranded conductor formed by regular stranding; Preferably, the rare earth metal includes any one or a combination of at least two of La, Ce, Y, Sc or Er, and more preferably a combination of La and Ce; Preferably, the mass ratio of La to Ce is (1~3):1; Preferably, the material of the insulating layer includes silicone rubber; Preferably, the material of the shielding layer includes tin-plated copper wire and aluminum foil; Preferably, based on a mass fraction of 100% for the tin-plated copper wire, the tin content in the tin-plated copper wire is 0.5% to 1.5%; Preferably, the shielding layer comprises tin-plated copper wire and aluminum foil spirally wound in sequence; Preferably, the material of the outer protective layer includes silicone rubber.

3. The aluminum alloy cable according to claim 1 or 2, characterized in that, The diameter of the aluminum alloy conductor tube is 0.3~0.5mm; Preferably, the thickness of the insulating layer is 0.5~1mm; Preferably, the thickness of the shielding layer is 0.1~0.2mm; Preferably, the thickness of the outer protective layer is 0.8~1.6mm.

4. A method for preparing an aluminum alloy cable according to any one of claims 1-3, characterized in that, The preparation method includes the following steps: (1) Preparation of aluminum alloy conductor tube: molten aluminum ingot and first alloy are mixed in a mass ratio of (97.65~99.5):1 and subjected to a first heat treatment to obtain a first mixture. Then, the first mixture is subjected to a first refining treatment and a second refining treatment to obtain aluminum alloy monofilament. The aluminum alloy monofilament is used to prepare aluminum alloy conductor tube. The first alloy comprises Al-RE master alloy, Fe, Cu, and Mg; the mass ratio of Al-RE master alloy, Fe, Cu, and Mg in the first alloy is (97~99):(5~18):(1.5~3):(0.1~0.5); the mass content of RE in the Al-RE master alloy is 5~10%. (2) The aluminum alloy conductor tube is wrapped with an insulation layer, a shielding layer and a sheath layer in sequence to obtain the aluminum alloy cable.

5. The preparation method according to claim 4, characterized in that, The preparation of the molten aluminum ingot includes: preheating the aluminum ingot to obtain the molten aluminum ingot; Preferably, the purity of the aluminum ingot is ≥99.7%; Preferably, the temperature of the preheating treatment is 720~750℃; Preferably, the preheating treatment time is 6-8 hours; Preferably, the first alloy further comprises Si and Mn; Preferably, the mass ratio of Al-RE master alloy, Si and Mn in the first alloy is (97~99):(3~10):1; Preferably, the RE in the Al-RE master alloy includes any one or a combination of at least two of La, Ce, Y, Sc or Er, and is preferably a combination of La and Ce; Preferably, the mass ratio of La to Ce is (1~3):1; Preferably, the temperature of the first heat treatment is 750~800℃; Preferably, the first heat treatment time is 5 to 10 minutes.

6. The preparation method according to claim 4 or 5, characterized in that, The temperature of the first refining process is 750~800℃; Preferably, the first refining process takes 10-20 minutes; Preferably, the first refining agent used in the first refining process includes a chloride-fluoride composite refining agent; Preferably, the mass ratio of chloride salt to fluoride salt in the first refining agent is (3~8):1; Preferably, the chloride salt includes NaCl and KCl; Preferably, the fluoride salt comprises Na3AlF6 and CaF2; Preferably, based on a mass fraction of 100% for the chloride-fluoride composite refining agent, the chloride salt comprises 40-50% NaCl and 30-40% KCl; Preferably, based on a mass fraction of 100% for the chloride-fluoride composite refining agent, the fluoride salt comprises 8-12% Na3AlF6 and 3-5% CaF2; Preferably, the temperature of the second refining process is 750~800℃; Preferably, the second refining process takes 10-20 minutes; Preferably, the second refining agent used in the second refining process includes BF3 and C2Cl6; Preferably, the mass ratio of BF3 to C2Cl6 in the second refining agent is (1~3):1; Preferably, the first refining process and the second refining process are each performed independently in ultrasound.

7. The preparation method according to any one of claims 4-6, characterized in that, The preparation of the aluminum alloy conductor tube includes: sequentially performing regular stranding and annealing treatment on the aluminum alloy monofilament to obtain the aluminum alloy conductor tube; Preferably, the stranding pitch in the regular stranding is 10 to 15 times the diameter of the aluminum alloy monofilament; Preferably, the annealing temperature is 180~220℃; Preferably, the annealing process takes 12 to 14 hours.

8. The preparation method according to any one of claims 4-7, characterized in that, The preparation of the insulating material of the insulating layer includes: mixing the basic raw materials of the insulating material, bis(2,4) vulcanizing agent, defrosting agent and color paste to obtain a second mixture; performing a kneading treatment on the second mixture to obtain an insulating rubber compound; and performing an extrusion vulcanization molding treatment on the insulating rubber compound to obtain the insulating material. Preferably, in the second mixing process, the mass ratio of the base raw material, bis(2,4) vulcanizing agent, defrosting agent and color paste is 100:(1.2~1.5):(0.3~0.5):(0.9~1.0); Preferably, the mixing temperature is 10~25℃; Preferably, the mixing process takes 8 to 10 minutes.

9. The preparation method according to claim 8, characterized in that, The extrusion vulcanization molding process includes an eight-stage extrusion vulcanization process. Preferably, the extrusion vulcanization process includes a first extrusion vulcanization process, a second extrusion vulcanization process, a third extrusion vulcanization process, a fourth extrusion vulcanization process, a fifth extrusion vulcanization process, a sixth extrusion vulcanization process, a seventh extrusion vulcanization process, and an eighth extrusion vulcanization process performed sequentially. Preferably, the extrusion temperature of the first extrusion vulcanization treatment is 750~850℃; Preferably, the extrusion temperature of the second extrusion vulcanization treatment is 650~740℃; Preferably, the extrusion temperature of the third extrusion vulcanization treatment is 550~640℃; Preferably, the extrusion temperatures of the fourth extrusion vulcanization process, the fifth extrusion vulcanization process, and the sixth extrusion vulcanization process are each independently 150~250°C; Preferably, the extrusion temperature of the seventh extrusion vulcanization process and the eighth extrusion vulcanization process are each independently 350~450°C.

10. The preparation method according to any one of claims 4-9, characterized in that, The preparation of the shielding layer includes: winding tin-plated copper wire around the outside of the insulating layer to form a two-layer structure with forward and reverse spirals, one layer spiraling left and the other spiraling right; and then winding aluminum foil around the outside of the tin-plated copper wire. Preferably, the tin-plated copper wire is wound at an angle of 50~65°; Preferably, the thickness of the left-handed structural layer is 0.11~0.2mm; Preferably, the thickness of the right-handed structural layer is 0.11~0.2 mm; Preferably, the material of the sheath layer includes silicone rubber.

Images