Enameled round graphene aluminum alloy winding wire and production process thereof

Abstract

The invention relates to the technical field of wires and cables, and particularly discloses an enameled round graphene aluminum alloy winding wire and a production process thereof. The enameled round graphene aluminum alloy winding wire comprises a graphene aluminum alloy conductive wire core and an insulating layer, the insulating layer comprises a polyimide heat-resistant layer and a ceramic protective layer, the polyimide heat-resistant layer is located between the graphene aluminum alloy conductive wire core and the ceramic protective layer, and the ceramic protective layer is located between the graphene aluminum alloy conductive wire core and the ceramic protective layer. The ceramic protective layer is prepared from the following raw materials in parts by weight: 30 to 50 parts of low-density polyethylene, 40 to 60 parts of ethylene-octylene copolymer, 50 to 80 parts of low-melting-point ceramic powder, 3 to 5 parts of vulcanizing agent, 5 to 8 parts of antioxidant and 5 to 8 parts of lubricating agent; the winding wire prepared by the invention has relatively good heat resistance and strength under the synergistic effect of all the components.

Description

Technical Field

[0001] This application relates to the technical field of wire and cable, and in particular to an enameled round graphene aluminum alloy winding wire and its production process. Background Art

[0002] Currently, enameled round wires are widely used in electrical equipment, such as power transformers, high-voltage motors, and other occasions that require high-performance winding wires. Traditional enameled wires mostly use copper or aluminum as the conductive wire core, and an insulating paint layer such as polyester, polyurethane, or polyimide is coated on the outer layer.

[0003] However, the electrical conductivity and mechanical strength of pure aluminum or aluminum alloy conductors are relatively low, while copper conductors have a high cost and exhibit a skin effect in high-frequency applications, affecting the transmission efficiency. Conventional organic insulating layers have poor heat resistance and are prone to burning and releasing toxic gases under high-temperature or open-fire conditions, making it difficult to meet the high-safety requirements in fields such as new energy vehicles and aerospace. Summary of the Invention

[0004] In order to improve the electrical performance, strength, and heat resistance of existing enameled round wires, this application provides an enameled round graphene aluminum alloy winding wire and its production process.

[0005] In a first aspect, this application provides an enameled round graphene aluminum alloy winding wire, adopting the following technical solution: An enameled round graphene aluminum alloy winding wire includes a graphene aluminum alloy conductive wire core and an insulating layer. The insulating layer includes a polyimide heat-resistant layer and a ceramicized protective layer. The polyimide heat-resistant layer is located between the graphene aluminum alloy conductive wire core and the ceramicized protective layer. The ceramicized protective layer includes the following raw materials in parts by weight: 30 - 50 parts of low-density polyethylene, 40 - 60 parts of ethylene-octene copolymer, 50 - 80 parts of low-melting-point porcelain powder, 3 - 5 parts of vulcanizing agent, 5 - 8 parts of antioxidant, and 5 - 8 parts of lubricant.

[0006] By adopting the above technical solution, the addition of graphene can improve the strength of the aluminum alloy wire core and enhance the electrical performance of the winding wire. At the same time, introducing a polyimide heat-resistant layer between the graphene aluminum alloy conductive wire core and the ceramicized protective layer can provide preliminary heat resistance protection for the winding wire, and the ceramicized protective layer provides a second layer of protection, thereby providing double heat resistance protection for the conductive wire core and improving the durability of the winding wire in a high-temperature environment.

[0007] In the raw materials of the ceramified protective layer, the low-melting-point ceramifying powder is combined with low-density polyethylene and ethylene-octene copolymer. At room temperature, it can make the ceramified protective layer have good flexibility and impact strength. When exposed to high temperatures or open flames, it can quickly ceramify to form a ceramic-like porcelain product with certain strength and self-supporting ability, providing fire protection for the conductive wire core and improving the fire safety and heat resistance of the winding wire. At the same time, the low-melting-point ceramifying powder can accelerate the ceramification process and improve the fire protection effect of the ceramified protective layer. The ethylene-octene copolymer can reduce the phenomenon of brittle cracking of the ceramified protective layer, improve the flexibility of the ceramified protective layer, and the ethylene-octene copolymer can form crosslinks with polyimide to improve the bonding strength between the insulating layers and enhance the flexibility and impact strength of the winding wire.

[0008] Preferably, the low-melting-point ceramifying powder is one of phosphate glass powder and borosilicate glass powder.

[0009] Preferably, the surface of the low-melting-point ceramifying powder is modified with γ-methacryloxypropyltrimethoxysilane. The modification method includes the following specific steps: Mix γ-methacryloxypropyltrimethoxysilane with the low-melting-point ceramifying powder, stir evenly, and obtain the modified low-melting-point ceramifying powder after heating and drying.

[0010] By adopting the above technical solution, the surface of the low-melting-point ceramifying powder is modified with γ-methacryloxypropyltrimethoxysilane, which can reduce the moisture absorption phenomenon of the ceramifying powder, and thus improve the strength and electrical properties of the ceramified protective layer.

[0011] Preferably, the mass ratio of γ-methacryloxypropyltrimethoxysilane to the low-melting-point ceramifying powder is (0.5 - 1):10.

[0012] Preferably, the polyimide heat-resistant layer comprises the following raw materials in parts by weight: 30 - 40 parts of polyimide resin, 5 - 10 parts of nano-zinc oxide, 5 - 10 parts of polycarbonate, and 5 - 10 parts of mesoporous silica.

[0013] By adopting the above technical solution, the polyimide resin can provide good high-temperature resistance for the conductive wire core and ensure good electrical insulation performance. At the same time, it has good strength and dimensional stability, enhancing the durability of the winding wire. The polycarbonate can improve the brittleness of the polyimide, making the polyimide heat-resistant layer have good flexibility and flexural fatigue resistance, enhancing the interfacial adhesion between the polyimide heat-resistant layer and the ceramified protective layer, and enhancing the protective effect of the insulating layer on the conductive wire core.

[0014] Adding an appropriate amount of nano-zinc oxide and mesoporous silica to the polyimide heat-resistant layer can synergistically enhance the effect, accelerate the heat dissipation from the conductive wire core to the outside, reduce the risk of local overheating, and at the same time reduce the thermal shrinkage of the polyimide heat-resistant layer at high temperatures, and improve the impact strength and high-temperature resistance of the polyimide heat-resistant layer.

[0015] Preferably, the pore diameter of the mesoporous silica is 20-40 nm.

[0016] Preferably, the graphene-aluminum alloy conductive wire core comprises the following raw materials in parts by weight: 85-95 parts of aluminum, 1-3 parts of copper, 0.3-0.5 parts of graphene, and 0.03-0.05 parts of rare earth.

[0017] By adopting the above technical solution, the combination of graphene and aluminum can enhance the tensile strength of the wire core. At the same time, graphene can synergistically enhance the effect with rare earth, inhibit grain growth, and improve the high-temperature stability of the wire core.

[0018] Preferably, the rare earth is at least one of lanthanum, cerium, and scandium.

[0019] In a second aspect, the present application provides a production process for an enameled round graphene-aluminum alloy winding wire, adopting the following technical solution: A production process for an enameled round graphene-aluminum alloy winding wire includes the following specific steps: Mix and open mill low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramizing powder, vulcanizing agent, antioxidant, and lubricant to form a ceramized protective layer mixture; Pre-compound the graphene-aluminum alloy conductive wire core with the polyimide heat-resistant layer in advance, and then melt and extrude the ceramized protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramized protective layer, thereby obtaining the enameled round graphene-aluminum alloy winding wire.

[0020] By adopting the above technical solution, the strength, electrical performance, and heat-resistant and fireproof performance of the enameled round graphene-aluminum alloy winding wire can be improved, enabling the winding wire to still maintain good performance in a high-temperature environment.

[0021] Preferably, the production process for the enameled round graphene-aluminum alloy winding wire includes the following specific steps: Mix, heat, and melt aluminum, copper, graphene, and rare earth to obtain a metal liquid, and cast, roll, and draw the metal liquid to obtain a graphene-aluminum alloy conductive wire core; Mix polyimide resin, nano-zinc oxide, polycarbonate, and mesoporous silica evenly, and melt and extrude them on the surface of the graphene-aluminum alloy conductive wire core to form a polyimide heat-resistant layer; Mix low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramizing powder, vulcanizing agent, antioxidant and lubricant by open mill to form a ceramizing protective layer mixture. Then melt and extrude the ceramizing protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramizing protective layer, thus obtaining an enameled round graphene aluminum alloy winding wire.

[0022] In summary, the present application has the following beneficial effects: 1. Since the present application uses graphene combined with aluminum alloy to form a conductive wire core, it can enhance the strength and electrical performance of the wire core. The conductive wire core is double-protected by the polyimide heat-resistant layer and the ceramizing protective layer, which can enhance the heat resistance, strength and durability of the winding wire. The combination of low-melting-point ceramizing powder with low-density polyethylene and ethylene-octene copolymer provides fire protection for the conductive wire core and improves the fire safety and heat resistance of the winding wire.

[0023] 2. In the present application, polycarbonate is used in combination with polyimide resin in the polyimide heat-resistant layer to improve the high-temperature resistance of the conductive wire core and ensure the electrical performance of the winding wire. At the same time, the synergistic effect of nano-zinc oxide and mesoporous silica is utilized to accelerate the heat dissipation from the conductive wire core to the outside, reduce the risk of local overheating, and improve the impact resistance and high-temperature resistance of the polyimide heat-resistant layer. Specific embodiments

[0024] The following further elaborates on the present application in conjunction with embodiments.

[0025] All raw materials in the embodiments can be obtained commercially. Embodiments

[0026] Embodiment 1 This embodiment provides an enameled round graphene aluminum alloy winding wire, which includes a graphene aluminum alloy conductive wire core and an insulating layer. The insulating layer includes a polyimide heat-resistant layer and a ceramizing protective layer, and the polyimide heat-resistant layer is located between the graphene aluminum alloy conductive wire core and the ceramizing protective layer.

[0027] The ceramizing protective layer includes the following raw materials in parts by weight: 40 kg of low-density polyethylene, 50 kg of ethylene-octene copolymer, 65 kg of low-melting-point ceramizing powder, 4 kg of vulcanizing agent, 7 kg of antioxidant, and 7 kg of lubricant. The polyimide heat-resistant layer is polyimide resin.

[0028] The graphene aluminum alloy conductive wire core includes the following raw materials in parts by weight: 90 kg of aluminum, 2 kg of copper, 0.4 kg of graphene, and 0.04 kg of rare earth.

[0029] Among them, the low-melting-point ceramizing powder is phosphate glass powder, purchased from Guangdong Nanhai Donggu New Materials Co., Ltd.; the density of low-density polyethylene is 0.915 g / cm 3, the vulcanizing agent is dicumyl peroxide, the antioxidant is antioxidant 1010, the lubricant is zinc stearate, the ethylene-octene copolymer is Dow POE-8999, the polyimide resin is Mitsui PL450A of Japan, and the rare earth is lanthanum.

[0030] The production process of the enameled round graphene aluminum alloy winding wire includes the following specific steps: S1: Mix aluminum, copper, graphene and rare earth and heat them to 750 °C to melt, obtain the metal liquid, and cast, roll and draw the metal liquid to obtain the graphene aluminum alloy conducting wire core.

[0031] S2: Mix low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramizing powder, vulcanizing agent, antioxidant and lubricant and open mill at 180 °C to form the ceramizing protective layer mixture.

[0032] S3: Heat the polyimide resin to 400 °C and extrude it on the surface of the graphene aluminum alloy conducting wire core to form a polyimide heat-resistant layer with an average thickness of 10 μm, and then extrude the ceramizing protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramizing protective layer with an average thickness of 10 μm, thus obtaining the enameled round graphene aluminum alloy winding wire.

[0033] Example 2 The difference between Example 2 and Example 1 is that in the raw materials of the ceramizing protective layer, the usage amount of low-density polyethylene is 30 kg, the usage amount of ethylene-octene copolymer is 60 kg, the usage amount of low-melting-point ceramizing powder is 50 kg, the usage amount of vulcanizing agent is 3 kg, the usage amount of antioxidant is 5 kg, and the usage amount of lubricant is 8 kg.

[0034] Example 3 The difference between Example 3 and Example 1 is that in the raw materials of the ceramizing protective layer, the usage amount of low-density polyethylene is 50 kg, the usage amount of ethylene-octene copolymer is 40 kg, the usage amount of low-melting-point ceramizing powder is 80 kg, the usage amount of vulcanizing agent is 5 kg, the usage amount of antioxidant is 8 kg, and the usage amount of lubricant is 5 kg.

[0035] Example 4 The difference between Example 4 and Example 1 is that in the raw materials of the graphene aluminum alloy conducting wire core, the usage amount of aluminum is 85 kg, the usage amount of copper is 1 kg, the usage amount of graphene is 0.3 kg, and the usage amount of rare earth is 0.05 kg.

[0036] Example 5 The difference between Example 5 and Example 1 is that in the raw materials of the graphene aluminum alloy conducting wire core, the usage amount of aluminum is 95 kg, the usage amount of copper is 3 kg, the usage amount of graphene is 0.5 kg, and the usage amount of rare earth is 0.03 kg.

[0037] Example 6 Example 6 is different from Example 1 in that the polyimide heat-resistant layer comprises the following raw materials in parts by weight: 35 kg of polyimide resin, 8 kg of nano zinc oxide, 8 kg of polycarbonate, and 8 kg of mesoporous silica. The average particle size of the nano zinc oxide is 50 nm, the diameter of the mesoporous silica is 20 - 40 nm, and the molecular weight Mw of the polycarbonate is 20,000.

[0038] The production process of the enameled round graphene aluminum alloy winding wire comprises the following specific steps: S1: Mix aluminum, copper, graphene, and rare earth, heat them to 750 °C for melting to obtain a metal liquid, and then cast, roll, and draw the metal liquid to obtain a graphene aluminum alloy conductive wire core.

[0039] S2: Mix low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramizing powder, vulcanizing agent, antioxidant, and lubricant, and open mill them at 180 °C to form a ceramized protective layer mixture.

[0040] S3: Mix the polyimide resin, nano zinc oxide, polycarbonate, and mesoporous silica evenly, and melt-extrude them on the surface of the graphene aluminum alloy conductive wire core at 400 °C to form a polyimide heat-resistant layer with an average thickness of 10 μm. Then, extrude the ceramized protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramized protective layer with an average thickness of 10 μm, thus obtaining the enameled round graphene aluminum alloy winding wire.

[0041] Example 7 Example 7 is different from Example 6 in that the usage amount of the polyimide resin in the raw materials of the polyimide heat-resistant layer is 30 kg, the usage amount of the nano zinc oxide is 5 kg, the usage amount of the polycarbonate is 10 kg, and the usage amount of the mesoporous silica is 10 kg.

[0042] Example 8 Example 8 is different from Example 6 in that the usage amount of the polyimide resin in the raw materials of the polyimide heat-resistant layer is 40 kg, the usage amount of the nano zinc oxide is 10 kg, the usage amount of the polycarbonate is 5 kg, and the usage amount of the mesoporous silica is 5 kg.

[0043] Example 9 Example 9 is different from Example 6 in that the polycarbonate is not used in the raw materials of the polyimide heat-resistant layer.

[0044] Example 10 Example 10 is different from Example 6 in that the mesoporous silica is not used in the raw materials of the polyimide heat-resistant layer.

[0045] Example 11 Example 11 is different from Example 6 in that the surface of the low-melting-point ceramizable powder in the raw material of the ceramization protective layer is modified with γ-methacryloxypropyltrimethoxysilane. The production process of the enameled round graphene aluminum alloy winding wire includes the following specific steps: S1: Mix aluminum, copper, graphene and rare earth and heat them to 750 °C for melting to obtain a metal liquid. Cast, roll and draw the metal liquid to obtain a graphene aluminum alloy conductive wire core.

[0046] S2: Mix γ-methacryloxypropyltrimethoxysilane with the low-melting-point ceramizable powder and stir evenly. The mass ratio of γ-methacryloxypropyltrimethoxysilane to the low-melting-point ceramizable powder is 0.8:10. After heating and drying, the modified low-melting-point ceramizable powder is obtained. Mix low-density polyethylene, ethylene-octene copolymer, modified low-melting-point ceramizable powder, vulcanizing agent, antioxidant and lubricant and knead them at 180 °C to form a ceramization protective layer mixture.

[0047] S3: Mix polyimide resin, nano-zinc oxide, polycarbonate and mesoporous silica evenly, and melt and extrude them on the surface of the graphene aluminum alloy conductive wire core at 400 °C to form a polyimide heat-resistant layer with an average thickness of 10 μm. Then extrude the ceramization protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramization protective layer with an average thickness of 10 μm, thus obtaining the enameled round graphene aluminum alloy winding wire.

[0048] Comparative example Comparative example 1 Comparative example 1 is different from Example 1 in that the ceramization protective layer is not used in the raw material of the enameled round graphene aluminum alloy winding wire.

[0049] Comparative example 2 Comparative example 2 is different from Example 1 in that the low-melting-point ceramizable powder is not used in the raw material of the ceramization protective layer.

[0050] Comparative example 3 Comparative example 3 is different from Example 1 in that the polyimide heat-resistant layer is not used in the raw material of the enameled round graphene aluminum alloy winding wire.

[0051] Performance detection test Perform the following performance detections on the enameled round graphene aluminum alloy winding wires provided in Examples 1-11 and Comparative examples 1-3 of the present application. The specific detection results are shown in Table 1.

[0052] Detection method I. Mechanical properties and thermal aging properties Refer to the standard of GB / T 2951.11-2008 "General test methods for insulating and sheathing materials of cables and optical cables - Part 11: General test methods - Measurement of dimensions and mechanical properties", and detect the elongation at break of the prepared enameled round graphene aluminum alloy winding wire. Test according to GB / T1040.3-2006 "Determination of tensile properties of plastics - Part 3: Test conditions for thin plastics and films", and detect the tensile strength of the enameled round graphene aluminum alloy winding wire prepared in this application, with a tensile speed of 250 mm / min. Test according to the standard of GB / T2951.12-2008 "General test methods for insulating and sheathing materials of cables and optical cables - Part 12: General test methods - Thermal aging test", with the aging conditions of 168 h and 100 °C, and detect the tensile strength after aging.

[0053] II. Volume resistivity Test according to GB / T 1410-2006 "Test methods for volume resistivity and surface resistivity of solid insulating materials", and the test temperature is 20 °C.

[0054] III. Fire resistance Refer to the standard of GB / T19216.21-2003 "Circuit integrity tests of cables or optical cables under fire conditions - Part 21: Test procedures and requirements - Cables with rated voltage 0.6 / 1.0 kV and below", and at a flame temperature of 800 °C, test whether the enameled round graphene aluminum alloy winding wire prepared in this application is qualified during the experiment.

[0055] Table 1: Data table of performance test results It can be seen from the performance test results that the enameled round graphene aluminum alloy winding wire prepared in this application has good heat resistance and fire safety. At the same time, under the synergistic effect of each component, it can also maintain good strength and electrical properties. By comparing Comparative Examples 1-3 with Example 1, it can be seen that in Comparative Example 1, the ceramicized protective layer is not used, and in Comparative Example 2, the low-melting-point ceramifying powder is not used. It can be seen from the performance test results that the fire resistance effect and heat resistance performance of the winding wire will both decrease significantly and lose its service performance in an environment containing open flames. Further explanation shows that using a single polyimide heat-resistant layer for heat protection of the conductive wire core has limited effects, and at the same time, it cannot maintain the safety of the winding wire in an open flame. In Comparative Example 3, the polyimide heat-resistant layer is not used. Although the prepared winding wire still has a fire resistance effect, its heat aging performance and strength are greatly reduced. Further explanation shows that only by combining the ceramicized protective layer and the polyimide heat-resistant layer in this application and synergistically enhancing the effect can the winding wire have good strength, aging resistance and fire resistance effect.

[0056] As can be seen from Examples 9-10, in Example 9, polycarbonate is not used, and in Example 10, mesoporous silica is not used. The heat aging resistance and tensile strength of the prepared winding wires both decrease significantly, further indicating that under the synergistic effect of each component, the polyimide heat-resistant layer can provide heat-resistant protection for the conductive wire core.

[0057] As can be seen from Example 11, the surface modification of the low-melting-point ceramizable powder with γ-methacryloxypropyltrimethoxysilane can reduce the moisture absorption phenomenon of the ceramizable powder, thereby improving the strength and electrical performance of the winding group.

[0058] This specific embodiment is only an interpretation of the present application, and it does not limit the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. An enameled round graphene aluminum alloy winding wire, characterized in that, It includes a graphene aluminum alloy conductive wire core and an insulating layer. The insulating layer includes a polyimide heat-resistant layer and a ceramifiable protective layer. The polyimide heat-resistant layer is located between the graphene aluminum alloy conductive wire core and the ceramifiable protective layer. The ceramifiable protective layer comprises the following raw materials in parts by weight: 30-50 parts of low-density polyethylene, 40-60 parts of ethylene-octene copolymer, 50-80 parts of low-melting-point ceramifiable powder, 3-5 parts of vulcanizing agent, 5-8 parts of antioxidant, and 5-8 parts of lubricant.

2. The enameled round graphene aluminum alloy winding wire according to claim 1, wherein The low-melting-point ceramifiable powder is one of phosphate glass powder and borosilicate glass powder.

3. The enameled round graphene aluminum alloy winding wire according to claim 2, characterized in that, The surface of the low-melting-point ceramifiable powder is modified by γ-methacryloxypropyltrimethoxysilane. The modification method includes the following specific steps: Mix γ-methacryloxypropyltrimethoxysilane with the low-melting-point ceramifiable powder, stir evenly, and obtain the modified low-melting-point ceramifiable powder after heating and drying.

4. The enameled round graphene aluminum alloy winding wire according to claim 3, characterized in that, The mass ratio of γ-methacryloxypropyltrimethoxysilane to the low-melting-point ceramifiable powder is (0.5-1):

10.

5. The enameled round graphene aluminum alloy winding wire according to claim 1, characterized in that, The polyimide heat-resistant layer comprises the following raw materials in parts by weight: 30-40 parts of polyimide resin, 5-10 parts of nano-zinc oxide, 5-10 parts of polycarbonate, and 5-10 parts of mesoporous silica.

6. The enameled round graphene aluminum alloy winding wire according to claim 5, characterized in that, The pore diameter of the mesoporous silica is 20-40 nm.

7. The enameled round graphene aluminum alloy winding wire according to claim 1, characterized in that, The graphene aluminum alloy conductive wire core comprises the following raw materials in parts by weight: 85-95 parts of aluminum, 1-3 parts of copper, 0.3-0.5 parts of graphene, and 0.03-0.05 parts of rare earth.

8. The enameled round graphene aluminum alloy winding wire according to claim 7, wherein, The rare earth is at least one of lanthanum, cerium, and scandium.

9. A production process of an enameled round graphene aluminum alloy winding wire as described in any one of claims 1-8, characterized in that, It includes the following specific steps: Mix and open mill low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramifiable powder, vulcanizing agent, antioxidant, and lubricant to form a ceramifiable protective layer mixture. Pre-compound the graphene aluminum alloy conductive wire core with the polyimide heat-resistant layer in advance, and then melt and extrude the ceramifiable protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramifiable protective layer, thus obtaining an enameled round graphene aluminum alloy winding wire.

10. The production process of the enameled round graphene aluminum alloy winding wire according to claim 9, characterized in that, It includes the following specific steps: Mix aluminum, copper, graphene, and rare earth, heat and melt them to obtain a metal liquid, and then cast, roll, and draw the metal liquid to obtain a graphene aluminum alloy conductive wire core. Mix polyimide resin, nano-zinc oxide, polycarbonate, and mesoporous silica evenly, and melt and extrude them on the surface of the graphene aluminum alloy conductive wire core to form a polyimide heat-resistant layer. Mix and open mill low-density polyethylene, ethylene-octene copolymer, low-melting-point ceramifiable powder, vulcanizing agent, antioxidant, and lubricant to form a ceramifiable protective layer mixture, and then melt and extrude the ceramifiable protective layer mixture on the surface of the polyimide heat-resistant layer to form a ceramifiable protective layer, thus obtaining an enameled round graphene aluminum alloy winding wire.

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