Aluminum alloy wiring harness and preparation method thereof

Abstract

The application provides an aluminum alloy wire harness and a method for preparing the same, which is designed for applications requiring high conductivity and excellent mechanical strength, such as new energy vehicles, photovoltaic solar panels, battery energy storage systems, and wind power generation equipment. The aluminum alloy wire harness includes an aluminum core conductor, an insulation layer, a shielding layer, and a protective layer arranged in sequence from the inside to the outside. The aluminum core conductor can be selected as a single solid aluminum alloy conductor or an aluminum alloy stranded wire, with any cross-sectional shape of circular, rectangular, rounded rectangular, and unicycle, and is made of Al-Mg-Si alloy, and is optimized through precise aging treatment process to obtain high strength and excellent conductivity. In addition, the end connector of the aluminum core conductor includes a copper nose, a copper silver-plated nose, or a nose pressed from an aluminum core conductor. The present invention adopts casting, extrusion, or drawing processes to simplify the process flow, save energy and time, and effectively reduce costs, thereby providing significant economic benefits.

Description

Technical Field

[0001] The present invention relates to the field of electrical connection technology, particularly to aluminum alloy wiring harnesses and methods for their preparation. These wiring harnesses are designed for applications requiring high electrical conductivity and excellent mechanical strength, and are suitable for applications such as new energy vehicles, photovoltaic solar panels, battery energy storage systems, and wind power generation equipment. Background Art

[0002] As technology advances, electronic devices and energy systems place increasing demands on the performance of electrical connector components, particularly in terms of conductivity and environmental corrosion resistance. While traditional copper-based wiring harnesses offer excellent conductivity, their heavy weight, high cost, and resource sustainability issues limit their application. Aluminum alloys, with their lightweight, cost-effectiveness, and excellent conductivity, are becoming a popular alternative.

[0003] However, in practical applications, aluminum alloy wiring harnesses still face numerous technical challenges, particularly in demanding applications such as the electrical systems of new energy vehicles and the electrical connections of renewable energy facilities. Current technology struggles to achieve an optimal balance between tensile strength and electrical conductivity. Furthermore, existing wiring harness preparation processes are complex, often requiring the assembly of multiple alloy materials, such as copper cores, copper wires, and aluminum shielding foil. This not only increases manufacturing costs but also impacts production efficiency.

[0004] Therefore, there is an urgent need to develop a new aluminum alloy wiring harness and its manufacturing method to overcome the shortcomings of existing technologies and provide a solution with a more optimized structure, more efficient manufacturing, lower cost, and less environmental impact. This new technology should be able to meet the stringent requirements of new energy vehicles, photovoltaics, and other applications, while achieving both economic and environmental goals. Summary of the Invention

[0005] The purpose of the embodiments of the present application is to provide an aluminum alloy wire harness and a method for preparing an aluminum alloy wire harness, which can reduce costs and reduce environmental impact while meeting the requirements of high conductivity and superior mechanical strength. This embodiment achieves performance improvement of aluminum alloy wire harnesses that are widely used in electrical and electronic equipment through innovative material selection and process optimization, and is particularly suitable for new energy vehicles, renewable energy systems and other fields that require lightweight and high-performance electrical connection solutions. The aluminum alloy wire harness not only improves conductivity and corrosion resistance by using specially treated Al-Mg-Si alloy, but also significantly enhances tensile strength and fatigue resistance through optimized alloy composition and heat treatment process. In addition, the preparation method of the present invention simplifies the production process, reduces energy consumption and production costs, and makes the aluminum alloy wire harness more environmentally friendly and economical, meeting the sustainable development requirements of modern industry.

[0006] In a first aspect, the present application provides an aluminum alloy wiring harness, comprising:

[0007] Aluminum alloy wiring harness mother body and terminal connectors;

[0008] The wiring harness mother body comprises an aluminum core conductor, an insulating layer, a shielding layer and a protective layer arranged in sequence from the inside to the outside;

[0009] The terminal connector is selected from any one of a copper nose, a copper silver-plated nose, or a nose pressed from one side of an aluminum core conductor. The terminal connector is provided at the end of the aluminum core conductor to achieve connection with other circuits or devices.

[0010] The aluminum core conductor may be a single solid aluminum alloy conductor or an aluminum alloy stranded wire, having a cross-sectional shape of any one of circular, rectangular, rounded rectangular and unitary circle, and a cross-sectional area of ​​100 to 200 mm²;

[0011] The aluminum core conductor is an Al-Mg-Si alloy, and its composition and proportion are Si 0.3-0.45%, Mg 0.40-0.55%, Cu<0.01%, Mn<0.005%, Cr<0.005%, Zn<0.01%, Ti<0.005%, Fe<0.1%, and other single elements<0.005%;

[0012] The aluminum core conductor has a tensile strength greater than 230 MPa, a yield strength greater than 200 MPa, an elongation greater than 15%, an electrical conductivity greater than 58% IACS, and a thermal expansion coefficient less than or equal to 22×10 -6 / ℃;

[0013] The insulating layer is a composite of PTFE and rubber solid solution material, which is co-extruded with the aluminum core conductor;

[0014] The shielding layer is an aluminum drawn tube, which is fastened to the insulating layer by mechanical expansion and contraction technology, has a wall thickness of 2-5 mm, and adopts 8 series alloy, whose composition and proportion are: Si<0.1%, Fe 0.3-0.6%, Cu<0.05%, Mn 0.8-1.2%, Mg<0.01%, Cr<0.02%, Ni<0.03%, Zn<0.02%, Ti<0.04%, and other single elements<0.005;

[0015] The protective layer is a mesh rubber material and is sleeved on the outside of the shielding layer.

[0016] In one embodiment, the aluminum core conductor of the aluminum alloy wiring harness has a Mg / Si mass ratio of 1.1-1.3, and Mn+Ti+Cr+Zn≤0.02%.

[0017] In one embodiment, the aluminum core conductor of the aluminum alloy wiring harness is heat-treated, and the heat-treated state is any one of T61, T63, T64, and T65; in the microstructure of the aluminum core conductor, a second phase exists in the aluminum matrix, and the second phase is a β" phase, and the number density of the β" phase is not less than 0.8×10 23 per cubic meter, and the volume fraction is not less than 1.5%; in the structure of the aluminum core conductor, the excess Mg content is not higher than 0.07%, and the excess Si content is not higher than 0.05%.

[0018] In one embodiment, when the aluminum core conductor of the aluminum alloy wiring harness is a single solid aluminum alloy conductor, its end connector is designed to press the two ends of the aluminum alloy conductor into ends of a specific shape; when the aluminum core conductor is an aluminum alloy stranded wire, the end connector is selected from either a copper nose or a copper-plated silver nose, and is fixedly connected to the aluminum alloy stranded wire through ultrasonic welding technology to ensure the reliability and electrical performance of the connection.

[0019] In a second aspect, the present application provides a method for preparing an aluminum alloy wiring harness, comprising the following steps:

[0020] (1) Preparation of aluminum core conductor;

[0021] (2) Co-extruding the aluminum core conductor and the insulation layer;

[0022] (3) Condensed aluminum shielding layer and insulation layer;

[0023] (4) Preparing an end connector, including preparing one end of an aluminum core conductor into an end connector or welding one end of an aluminum core conductor to an existing end connector;

[0024] or (5) bending the aluminum alloy wire harness into a fixed shape;

[0025] (6) Put on the protective cover;

[0026] (7) Install the end fixings.

[0027] In one embodiment, the method for preparing the aluminum alloy wire harness is to prepare the aluminum core conductor by any of the following process flows according to product performance requirements and manufacturing conditions:

[0028] 1) A process flow suitable for preparing a single solid aluminum alloy conductor with medium strength and high conductivity, comprising the following steps:

[0029] a. Prepare raw materials according to alloy composition;

[0030] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt;

[0031] c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod;

[0032] e. Solution treatment of aluminum alloy round rods at 520-540℃ and water cooling;

[0033] i. Perform tensile straightening treatment;

[0034] k. Carry out aging treatment;

[0035] 2) A process flow suitable for preparing medium-strength, high-conductivity aluminum alloy stranded wire includes the following steps:

[0036] a. Prepare raw materials according to alloy composition;

[0037] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt;

[0038] c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod;

[0039] e. Solution treatment of aluminum alloy round rods at 520-540℃ and water cooling;

[0040] j. The processed aluminum alloy round rod is drawn into aluminum alloy wire;

[0041] k. Carry out aging treatment;

[0042] 3) A process flow suitable for preparing a single solid aluminum alloy conductor with high strength and high conductivity, comprising the following steps:

[0043] a. Prepare raw materials according to alloy composition;

[0044] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities;

[0045] d. Casting the aluminum alloy melt into aluminum alloy round cast rods;

[0046] f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃;

[0047] g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles;

[0048] h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles;

[0049] i. Perform tensile straightening treatment;

[0050] k. Carry out aging treatment;

[0051] 4) A process flow suitable for preparing high-strength, high-conductivity aluminum alloy stranded wire includes the following steps:

[0052] a. Prepare raw materials according to alloy composition;

[0053] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities;

[0054] d. Casting the aluminum alloy melt into aluminum alloy round cast rods;

[0055] f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃;

[0056] g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles;

[0057] h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles;

[0058] j. Drawing the processed aluminum alloy bars or profiles into aluminum alloy wires;

[0059] k. Carry out aging treatment.

[0060] In one embodiment, the method for preparing the aluminum alloy wire harness has a hydrogen content in the melt of less than 0.15 ml / 100 gAl and a slag content of less than 0.03 mm 2 / kgAl.

[0061] In one embodiment, in the method for preparing the aluminum alloy wire harness, the extrusion die temperature during extrusion of the aluminum alloy cast rod is 475-490°C, the extrusion barrel temperature is 455-470°C, the cast rod temperature is 510-525°C, the extrusion billet temperature is 525-540°C, and online heat treatment is performed after extrusion. The temperature of the aluminum alloy rod or profile after quenching is less than 180°C.

[0062] In one embodiment, in the method for preparing the aluminum alloy wire harness, the aging treatment can select any one of T61, T63, T64, and T65 aging processes, wherein the T61 aging treatment is performed in a temperature range of 215°C to 245°C for 4 to 8 hours; the T63 aging treatment is performed in a temperature range of 200°C to 230°C for 8 to 12 hours; the T64 aging treatment is performed in a temperature range of 260°C to 290°C for 6 to 9 hours; and the T65 aging treatment is performed in a temperature range of 205°C to 235°C for 2 to 5 hours.

[0063] On the third aspect, the present application provides an aluminum alloy wire harness, which is mainly used in the fields of electrical connection components of new energy vehicles, conductive frames of photovoltaic solar panels, conductive connectors of battery energy storage systems, conductive components of wind power generation devices, etc.

[0064] The beneficial effects of this application compared with the prior art are:

[0065] The present application provides a high-performance aluminum alloy wiring harness with high electrical conductivity and enhanced mechanical stability, meeting its application in the high-demand new energy vehicle and photovoltaic fields. The present application adopts a new Al-Mg-Si alloy system and adopts casting or extrusion or casting-drawing and extrusion-drawing processes to solve the problem of the difficulty in balancing electrical conductivity and mechanical strength in traditional aluminum alloy wiring harnesses. Through this technology, a corrosion-resistant aluminum alloy wiring harness is obtained. The preparation process of the present application also specifically optimizes the ratio of alloy elements and processing steps, with the advantages of high cost-effectiveness, improved production efficiency and low environmental impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0067] Figure 1 This is the cross-sectional shape of a circular aluminum core conductor shown in an embodiment of the present application.

[0068] Figure 2 The cross-sectional shape of a rectangular aluminum core conductor shown in an embodiment of the present application.

[0069] Figure 3 The cross-sectional shape of the rounded rectangular aluminum core conductor shown in one embodiment of the present application.

[0070] Figure 4 This is the cross-sectional shape of a unicyclic aluminum core conductor shown in an embodiment of the present application.

[0071] Figure 5 A schematic diagram of the preparation process of an aluminum alloy wiring harness according to an embodiment of the present application is shown.

[0072] Figure 6 This is a schematic diagram of the preparation process of a single solid aluminum alloy conductor with medium strength and high conductivity according to an embodiment of the present application.

[0073] Figure 7 This is a schematic diagram of the preparation process of medium-strength, high-conductivity aluminum alloy stranded wire shown in one embodiment of the present application.

[0074] Figure 8 This is a schematic diagram of the preparation process of a single solid aluminum alloy conductor with high strength and high conductivity according to one embodiment of the present application.

[0075] Figure 9 This is a schematic diagram of the preparation process of high-strength, high-conductivity aluminum alloy stranded wire shown in one embodiment of the present application.

[0076] Figure 10 This is a TEM image of the microstructure of a single solid aluminum alloy conductor according to an embodiment of the present application. DETAILED DESCRIPTION

[0077] The terms "first", "second", "third", etc. are only used to distinguish and describe, and do not indicate the order of arrangement, nor can they be understood as indicating or implying relative importance.

[0078] Furthermore, terms such as "horizontal," "vertical," and "overhanging" do not necessarily imply that a component must be absolutely horizontal or overhanging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but rather that it can be slightly tilted.

[0079] In the description of this application, it should be noted that the terms "inside", "outside", "left", "right", "up", "down", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limitations on this application.

[0080] In the description of this application, unless otherwise clearly specified and limited, the terms "set", "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or it can be internal communication between two components. If the specific conditions are not specified in the examples of this application, the conventional conditions or the conditions recommended by the manufacturer shall be followed. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially.

[0081] The technical solution of this application will be clearly and completely described below with reference to the accompanying drawings.

[0082] The present invention provides an aluminum alloy wiring harness, comprising an aluminum alloy wiring harness body and an end connector. The wiring harness body comprises an aluminum core conductor, an insulation layer, a shielding layer, and a protective layer, arranged in sequence from the inside out. The end connector is selected from a copper lug, a silver-plated copper lug, or a lug pressed from one side of the aluminum core conductor. The end connector is provided at the end of the aluminum core conductor to enable connection to other circuits or devices.

[0083] The aluminum alloy wiring harness design of this invention incorporates a multi-layer structure and specialized connector configurations. These design choices are designed to meet specific performance requirements and enhance the reliability and efficiency of the aluminum alloy wiring harness in practical applications. The aluminum core conductor is the primary electrical conductor in the wiring harness. Aluminum was chosen for its excellent conductivity, lightweight, and cost-effectiveness. The insulation layer prevents power leakage and electrical shorts, ensuring that current flows only within a predetermined path. This layer is typically made of a material with high electrical insulation properties, such as polytetrafluoroethylene (PTFE), to protect the inner conductor from external interference. The shielding layer provides protection against external electromagnetic interference (EMI) and ensures stable signal transmission within the wiring harness. This is particularly important for high-frequency communications equipment or dense electronic equipment environments. The outer shielding layer provides physical protection against mechanical damage, chemical corrosion, and environmental factors (such as humidity and temperature fluctuations). This layer is typically made of a wear-resistant material, such as rubber or specialized plastics, to extend the service life of the wiring harness.

[0084] Terminal connectors are made of copper or silver-plated copper because of its excellent electrical conductivity and corrosion resistance. The silver-plated copper nose provides copper's conductivity while the silver coating further enhances corrosion resistance and connection durability. Terminal connectors are installed at the end of the aluminum core conductor to facilitate a quick and stable electrical connection to other circuits or devices. Extruded connectors are selected to ensure mechanical strength and good contact performance, reducing contact resistance and improving transmission efficiency.

[0085] The aluminum core conductors in this application can be single solid aluminum alloy conductors or stranded aluminum alloy wires, with cross-sectional shapes ranging from circular, rectangular, rounded rectangular, and spherical, and a cross-sectional area of ​​100-200 mm². The aluminum core conductors in this application offer a variety of design options and flexibility. This flexibility enables aluminum alloy wiring harnesses to be used in a wide range of industrial environments, from heavy industry to precision electronics, providing reliable electrical connection solutions. Selecting different conductor types and cross-sectional shapes optimizes electrical performance, mechanical strength, and cost-effectiveness based on specific application requirements. Single solid aluminum alloy conductors: This type of conductor is made from a single piece of aluminum alloy and is typically used in applications requiring high strength and reliability. Solid conductors offer a simple structure, are wear-resistant, and exhibit low electrical resistance when conducting current. However, these conductors are generally thicker and difficult to bend during application, requiring pre-bending into a specific shape according to specific bending requirements or using a straight conductor. Stranded aluminum alloy wires: Made from multiple fine aluminum alloy wires, they offer improved flexibility and fatigue resistance. This structure makes the wire harness more durable when subjected to bending or vibration, making it suitable for use in dynamic applications such as electrical wiring inside automobiles and mobile equipment.

[0086] Diversity in cross-sectional shapes: Circular is the most common cross-sectional shape, offering uniform resistance characteristics and a simple manufacturing process. Rectangular cross-sections offer a larger surface area and are suitable for applications requiring maximum conductive area within a limited space. Rounded rectangles combine the characteristics of circular and rectangular shapes, with rounded corners that reduce wear on cables during routing and help improve the overall durability of the cable. Oval (elliptical) rectangles are suitable for applications with limited space, as the oval shape makes the cable more compact, facilitating installation and routing. The range of cross-sectional areas available (100-200mm²) allows for the selection of the appropriate size during design based on varying current loads and mechanical strength requirements. Conductors with larger cross-sectional areas can carry higher currents and are suitable for power transmission and large equipment, while conductors with smaller cross-sectional areas are suitable for signal transmission and lightly loaded circuits.

[0087] Figure 1 、 Figure 2 、 Figure 3 and Figure 4 The cross-sectional structures of aluminum alloy wire harnesses composed of a circular aluminum core conductor, a rectangular aluminum core conductor, a rounded rectangular aluminum core conductor, and a spherical aluminum core conductor are shown. In the figure, 1, 2, 3, and 4 represent the aluminum core conductor, the insulation layer, the shielding layer, and the protective layer, respectively.

[0088] The aluminum core conductor in this application is an Al-Mg-Si alloy with the following composition and ratios: Si 0.3-0.45%, Mg 0.40-0.55%, Cu <0.01%, Mn <0.005%, Cr <0.005%, Zn <0.01%, Ti <0.005%, Fe <0.1%, and other individual elements <0.005%. By controlling the content and ratio of these alloying elements, the microstructure and properties of the Al-Mg-Si alloy can be optimized, achieving a balance between high conductivity and good mechanical properties.

[0089] Silicon (Si) 0.3-0.45%: Silicon is one of the main alloying elements in Al-Mg-Si aluminum alloys. It forms the Mg2Si strengthening phase with magnesium, improving the material's strength. Silicon additions are typically controlled at 0.3-0.45% to ensure sufficient strengthening without excessively increasing resistivity.

[0090] Magnesium (Mg) 0.40-0.55%: Magnesium is another important alloying element that also participates in the formation of the Mg2Si strengthening phase. Mg additions are typically controlled at 0.40-0.55% to achieve good strengthening effects and adequate electrical conductivity.

[0091] Copper (Cu) <0.01%: Copper is an element that significantly increases resistivity. Therefore, in aluminum alloys that pursue high conductivity, the copper content should be as low as possible, usually controlled below 0.01%.

[0092] Manganese (Mn) <0.005%, Chromium (Cr) <0.005%, Zinc (Zn) <0.01%, Titanium (Ti) <0.005%, Iron (Fe) <0.1%: These elements are usually present as impurities and their content should be controlled at as low levels as possible to reduce the negative impact on conductivity.

[0093] The aluminum core conductor in this application has a tensile strength greater than 230 MPa, a yield strength greater than 200 MPa, an elongation greater than 15%, an electrical conductivity greater than 58% IACS, and a thermal expansion coefficient less than or equal to 22×10 -6 / ℃. The excellent properties of aluminum alloy conductors in terms of structural strength, durability, flexibility, conductivity and thermal stability make them an ideal choice for a variety of applications in the electrical and electronics industries. In particular, an elongation of more than 15% indicates that the aluminum alloy conductor can significantly elongate before breaking, has good toughness, and is suitable for applications that require flexibility, such as cable connections in mobile devices or vehicles. Conductivity is an indicator of the conductive performance of a material and is measured in units of the International Annealed Copper Standard (IACS). 58% IACS means that the conductivity of the aluminum alloy conductor reaches 58% of the conductivity of pure annealed copper, which is a very high value for non-copper materials. Thermal expansion coefficient ≤22×10 -6 / ℃ ensures that the aluminum alloy conductor has stable dimensions under temperature fluctuations.

[0094] In the present application, the insulating layer is a composite of PTFE and rubber solid solution material, which is co-extruded with the aluminum core conductor.

[0095] PTFE (polytetrafluoroethylene) is a material with excellent chemical stability and heat resistance, resulting in exceptional electrical insulation properties. PTFE also boasts an extremely low coefficient of friction and excellent corrosion resistance, allowing it to withstand extreme temperatures and harsh chemical environments. The rubber solid solution material provides excellent flexibility and mechanical protection, enhancing the insulation's tear and abrasion resistance, making the wiring harness more suitable for environments subject to high physical stress. Combining the high electrical insulation of PTFE with the mechanical protection of rubber, this composite insulation layer effectively prevents current leakage while protecting the internal conductor from physical damage. During manufacturing, the PTFE and rubber solid solution material are tightly bonded to the aluminum core conductor through a co-extrusion process. Co-extrusion is a highly efficient production technology that combines different material layers in a continuous process. This method not only improves production efficiency but also ensures a strong bond between the insulation layer and the conductor, enhancing overall structural integrity.

[0096] In this application, the shielding layer is an aluminum drawn tube, which is fastened to the insulating layer by mechanical expansion and contraction technology. The wall thickness is 2-5 mm and an 8 series alloy is used. Its composition and proportion are: Si < 0.1%, Fe 0.3-0.6%, Cu < 0.05%, Mn 0.8-1.2%, Mg < 0.01%, Cr < 0.02%, Ni < 0.03%, Zn < 0.02%, Ti < 0.04%, and other single elements < 0.005%.

[0097] The shielding layer in this application uses an aluminum drawn tube, and its design and material selection provide excellent shielding effect and mechanical strength for the aluminum alloy wiring harness. A drawn tube made of aluminum alloy is used as the shielding layer, which is made through a precise drawing process. Drawing is a plastic processing technology that can accurately control the size and wall thickness of the aluminum tube. This technology can ensure that the aluminum tube has a uniform wall thickness and a high degree of surface finish. Mechanical expansion and contraction technology is used to tightly combine the aluminum drawn tube with the insulation layer. Mechanical expansion refers to first mechanically expanding the diameter of the aluminum tube so that it can be fitted onto the outside of the insulation layer; then the aluminum tube is restored or slightly reduced in diameter through a contraction process to be tightly fixed on the insulation layer. This method provides an excellent mechanical locking effect and ensures that there is no gap between the shielding layer and the insulation layer, enhancing the stability of the overall structure.

[0098] The shielding layer is constructed from an 8-series aluminum alloy, which typically contains high levels of added elements such as copper and manganese, providing excellent mechanical properties and corrosion resistance. Silicon (Si) <0.1% provides strength and heat resistance; Fe (Iron) 0.3-0.6% enhances the alloy's hardness and strength; Cu (Copper) <0.05% improves plasticity and corrosion resistance; Mn (Manganese) 0.8-1.2% significantly enhances the alloy's strength and wear resistance; and Mg (Magnesium) <0.01% slightly impacts the alloy's hardness and strength. Cr (Chromium), Ni (Nickel), Zn (Zinc), and Ti (Titanium): These elements are present in lower concentrations primarily to fine-tune the alloy's properties, improving corrosion resistance and processing performance. Wall thicknesses range from 2-5mm, ensuring sufficient mechanical strength and shielding effectiveness, allowing the wiring harness to resist physical damage while effectively blocking electromagnetic interference.

[0099] Overall, the use of drawn aluminum tubing as the shielding layer, coupled with mechanical expansion and contraction techniques for fastening, and the selection of high-performance 8-series aluminum alloys, ensure that the aluminum alloy wiring harness provides effective shielding while also possessing excellent mechanical protection and durability. These design choices make the aluminum alloy wiring harness of the present invention well-suited for use in electronic and electrical systems, particularly those requiring high shielding effectiveness and mechanical strength.

[0100] In this application, the protective layer is a mesh rubber material that is placed on the outside of the shielding layer. The protective layer uses a mesh rubber material to cover the outside of the shielding layer to provide additional mechanical protection and environmental resistance, preventing physical damage and chemical corrosion, thereby enhancing the durability and reliability of the entire wiring harness.

[0101] Furthermore, in the composition of the aluminum core conductor in the present application, the mass ratio of Mg / Si is 1.1-1.3, and Mn+Ti+Cr+Zn≤0.02%.

[0102] An ideal Mg / Si ratio ensures sufficient Mg2Si strengthening phase formation to enhance strength while avoiding excessive free Si or Mg atoms, which increase resistivity and reduce conductivity. Generally, a Mg / Si ratio between 1.1 and 1.3 is considered optimal. This ensures the formation of the β" phase within an ideal range, optimizing the alloy's mechanical properties and heat resistance, providing a good balance of strength and conductivity while maintaining good ductility and workability. If the Mg / Si ratio is too high, there may be an excess of free Mg atoms, leading to increased resistivity; if the ratio is too low, there may be an excess of free Si atoms, similarly affecting conductivity. Limiting the combined content of Mn, Ti, Cr, and Zn to below 0.02% is primarily intended to avoid the negative impact of excessive alloying element additions on conductivity. Keeping the content of these elements low helps maintain the recrystallized structure, improving strength and conductivity.

[0103] Furthermore, the aluminum core conductor in the present application is heat-treated, and the heat-treated state is any one of T61, T63, T64, and T65; in the microstructure of the aluminum core conductor, a second phase exists in the aluminum matrix, and the second phase is a β" phase, and the number density of the β" phase is not less than 0.8×10 23 per cubic meter, and the volume fraction is not less than 1.5%; in the structure of the aluminum core conductor, the excess Mg content is not higher than 0.07%, and the excess Si content is not higher than 0.05%.

[0104] Artificial aging can be used to manipulate these precipitate characteristics, optimizing alloy properties. Different aging conditions (T6, T61, T63, T64, and T65) result in distinct precipitate characteristics, necessitating the selection of the appropriate aging process based on the specific application and performance requirements. For example, a T6 aging treatment typically results in finer precipitates, which improves strength but may slightly compromise conductivity. Meanwhile, a T64 aging treatment may result in larger precipitates, maintaining high conductivity but potentially lower strength than a T6 aging treatment.

[0105] In Al-Mg-Si alloys, the β" precipitate phase is considered to be an ideal precipitate phase because it can enhance strength while having little effect on conductivity. The β" precipitate phase is a metastable phase with a smaller size and higher relative conductivity. In contrast, the larger β' or β phase can provide higher strength, but it also has a greater negative impact on conductivity. Therefore, while pursuing strength and high conductivity, emphasis should be placed on promoting the formation of the β" precipitate phase and trying to avoid the formation of the β' or β phase caused by excessive aging. In this application, the number density of the β" phase is not less than 0.8×10 23 per cubic meter, with a volume fraction of no less than 1.5%, indicating a relatively abundant secondary phase, resulting in complete precipitation and very few solid solution atoms in the matrix, effectively improving the material's electrical conductivity and strength. Excess magnesium (Mg) and silicon (Si) contents are controlled to no more than 0.07% and 0.05%, respectively. This ensures that the Mg and Si elements in the alloy are primarily used to form the beneficial β" phase, rather than remaining as residual solid solution atoms. Controlling excess element content helps avoid a decrease in electrical conductivity, a process primarily controlled through alloy proportioning and aging.

[0106] In the microstructure of highly conductive aluminum alloys, the intracrystalline features can be clearly seen through transmission electron microscopy (TEM): Figure 10 In the middle, we can see the inner edge of the crystal <001> AlNeedle-shaped β" phases precipitated. These needle-shaped precipitates had a diameter of approximately 5 nm and a length of less than 200 nm. The figure also shows the presence of a small number of dislocations within the crystal, with the dislocations surrounding the needle-shaped β" phase attached to them, indicating that the presence of dislocations promotes the precipitation of the β" phase. The present invention achieves the formation of intracrystalline β" phases through precise control of the alloy composition and heat treatment process, which helps to improve the strength of the material. At the same time, due to its small size, its relatively weak electron scattering effect has a minimal impact on conductivity, achieving a balance between high conductivity and excellent strength.

[0107] Furthermore, in the present application, when the aluminum core conductor is a single solid aluminum alloy conductor, its end connector is designed to press the two ends of the aluminum alloy conductor into ends of a specific shape; when the aluminum core conductor is an aluminum alloy stranded wire, the end connector is selected from either a copper nose or a copper-plated silver nose, and is fixedly connected to the aluminum alloy stranded wire through ultrasonic welding technology to ensure the reliability and electrical performance of the connection.

[0108] In this application, the end connectors designed for different types of aluminum core conductors have their own unique configurations and connection technologies to ensure connection reliability and optimize electrical performance. For single solid aluminum alloy conductors, the end connectors are designed to press the two ends of the aluminum alloy conductor into specifically shaped end connectors. This pressed end connector provides better mechanical plugging and locking performance, ensuring the stability of the connection. The pressed end connector is integrated with the aluminum core conductor, which can effectively increase the contact area, thereby reducing contact resistance and improving the stability and conductivity efficiency of the electrical connection. When using aluminum alloy stranded wire, the end connector is selected as a copper nose or a copper-plated silver nose. Both copper and silver have excellent electrical conductivity. Choosing such materials as end connectors can further ensure the electrical conductivity of the entire connection system. The copper-plated silver nose not only provides the good electrical conductivity of copper, but the silver coating also increases corrosion resistance and oxidation resistance, making it suitable for applications in harsh environments. The end connector and the aluminum alloy stranded wire are fixedly connected using ultrasonic welding technology. Ultrasonic welding is a solid-state welding technology that does not require an external heat source and uses heat generated by ultrasonic vibrations to achieve a metal-to-metal connection. This welding technology is particularly effective for metals such as aluminum alloys and copper, and can achieve tight and highly conductive welds without overheating the materials. Using ultrasonic welding avoids the heat-affected zone issues that may occur in traditional welding, maintains the original properties of the conductor, and provides a strong mechanical and electrical connection.

[0109] This selection of end connector designs and connection technologies tailored to different types of aluminum conductors significantly improves the performance and reliability of aluminum alloy wiring harnesses in various applications. The pressed ends of the single solid aluminum alloy conductors and the ultrasonically welded copper lugs of the aluminum alloy strands are designed to maximize the efficiency and durability of the electrical connection, ensuring excellent performance under various operating conditions. This design approach not only improves product performance but also takes into account the ease of installation and maintenance.

[0110] The present invention also provides a method for preparing an aluminum alloy wiring harness, comprising the following steps:

[0111] 1) Prepare aluminum core conductor;

[0112] 2) Co-extrude the aluminum core conductor and insulation layer;

[0113] 3) Condensation aluminum shielding layer and insulation layer;

[0114] 4) preparing an end connector, including preparing one end of the aluminum core conductor into an end connector or welding one end of the aluminum core conductor to an existing end connector;

[0115] or 5) bending the aluminum alloy wire harness into a fixed shape;

[0116] 6) Put on the protective cover;

[0117] 7) Install the terminal fixings.

[0118] Aluminum alloy wire harness preparation process flow chart, see Figure 5 .

[0119] It is worth noting that 5) bending the aluminum alloy wire harness into a fixed shape is not a necessary step. When selecting a single solid aluminum alloy conductor, bending is required according to the application scenario; when selecting aluminum alloy stranded wire, bending is not required because the structure of the stranded wire itself provides better flexibility and resistance to bending stress.

[0120] The preparation method of the aluminum alloy wire harness in the present invention particularly emphasizes that the preparation of the aluminum core conductor is based on product performance requirements and manufacturing conditions, and any of the following four process flows can be selected:

[0121] Process 1: A process suitable for preparing a single solid aluminum alloy conductor with medium strength and high conductivity, including the following steps:

[0122] a. Prepare raw materials according to alloy composition;

[0123] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt;

[0124] c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod;

[0125] e. Solution treatment of aluminum alloy round rods at 520-540℃ and water cooling;

[0126] i. Perform tensile straightening treatment;

[0127] k. Carry out aging treatment;

[0128] A look at the process flow Figure 6 .

[0129] This process continuously casts and rolls aluminum alloy melt into round rods, which are then solution treated and water-cooled to optimize the microstructure. Stretching, straightening, and aging treatments are then performed to enhance the material's mechanical properties and electrical conductivity. This process not only ensures the uniformity and workability of the aluminum alloy, but also improves its overall performance. This method achieves highly efficient production through meticulous control of the material production process, resulting in a short process and high-quality products.

[0130] Process 2: The process for preparing medium-strength, high-conductivity aluminum alloy stranded wire includes the following steps:

[0131] a. Prepare raw materials according to alloy composition;

[0132] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt;

[0133] c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod;

[0134] e. Solution treatment of aluminum alloy round rods at 520-540℃ and water cooling;

[0135] j. The processed aluminum alloy round rod is drawn into aluminum alloy wire;

[0136] k. Carry out aging treatment;

[0137] Second view of process flow Figure 7 .

[0138] Continuous casting and rolling involves directly forming liquid aluminum alloy into round rods through a continuous casting and rolling process. This process is highly efficient and ensures consistent dimensional and microstructural uniformity. Continuous casting and rolling is a common method in modern metalworking, suitable for large-scale production. Its continuous nature allows for effective control of the mechanical properties and chemical composition of the finished product. Drawing involves passing pre-treated aluminum alloy round rods through a series of dies, gradually reducing their diameter to form fine aluminum alloy wire. This process not only further refines the material's grain structure but also enhances the wire's tensile strength and hardness. Drawing significantly hardens the material through cold work, contributing to improved mechanical properties of the final product. During solution quenching, the aluminum alloy round rods are heated to 520-540°C, a temperature range sufficient to dissolve most of the precipitated phases in the alloy into the aluminum matrix. This is followed by rapid cooling (water cooling) to prevent the reformation of the precipitates, thereby forming a supersaturated solid solution that prepares the material for subsequent aging treatment. Solution treatment improves the material's plasticity, facilitating the drawing process.

[0139] This process combines continuous casting and rolling to ensure material uniformity, solution quenching to enhance plasticity and workability, cold work hardening during drawing to improve mechanical strength, and aging treatment to precisely control the material's microstructure to enhance tensile strength and electrical conductivity. This comprehensive process layout not only improves production efficiency but also ensures the product has high electrical conductivity and excellent mechanical properties.

[0140] Process 3: A process suitable for preparing a single solid aluminum alloy conductor with high strength and high conductivity, comprising the following steps:

[0141] a. Prepare raw materials according to alloy composition;

[0142] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities;

[0143] d. Casting the aluminum alloy melt into aluminum alloy round cast rods;

[0144] f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃;

[0145] g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles;

[0146] h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles;

[0147] i. Perform tensile straightening treatment;

[0148] k. Carry out aging treatment;

[0149] Three views of the process Figure 8 .

[0150] Homogenization heat treatment of aluminum alloy round cast bars aims to eliminate the uneven microstructure and stress concentrations generated during the casting process. Heating at 550-570°C promotes uniform distribution of alloying elements within the aluminum matrix, improving processability and mechanical properties. The homogenized aluminum alloy bars are then extruded into bars or profiles of the desired shape. Extrusion further refines the grain size and enhances the material's mechanical strength. Depending on the material's shape and cross-sectional area, either in-line or off-line solution quenching can be selected. This treatment locks in the supersaturated solid solution state of alloying elements within the aluminum matrix through rapid cooling (quenching), preparing the appropriate microstructure for subsequent aging. Aging after off-line solution quenching promotes better precipitation, resulting in improved electrical conductivity and strength. While in-line solution quenching yields slightly lower strength and conductivity, it offers a shorter, more efficient, and lower-cost process. Stretching straightening improves the straightness and geometric accuracy of the quenched material. Furthermore, stretching is a cold working process, introducing dislocations that facilitate precipitation during aging.

[0151] Process 4: The process for preparing high-strength and high-conductivity aluminum alloy stranded wire includes the following steps:

[0152] a. Prepare raw materials according to alloy composition;

[0153] b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities;

[0154] d. Casting the aluminum alloy melt into aluminum alloy round cast rods;

[0155] f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃;

[0156] g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles;

[0157] h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles;

[0158] j. Drawing the processed aluminum alloy bars or profiles into aluminum alloy wires;

[0159] k. Carry out aging treatment.

[0160] Four points of process flow Figure 9 .

[0161] Drawing, a cold working process, generates numerous dislocations within the material. These dislocations serve as nucleation sites for precipitation phases, accelerating precipitation hardening and ultimately increasing the alloy's strength and conductivity. Cold working also allows aluminum alloys to be produced to desired sizes and shapes, such as wires of varying diameters, expanding their applications in electrical connectors and high-voltage wiring harnesses.

[0162] Furthermore, the hydrogen content in the aluminum alloy melt of the present invention should be less than 0.15ml / 100gAl, and the slag content should be less than 0.03mm 2 / kgAl. Hydrogen content is an important parameter that needs to be controlled during the smelting process of aluminum alloys. Aluminum alloys easily absorb hydrogen during the melting process to form hydrogen solutes. When the alloy solidifies, the hydrogen dissolved in the aluminum alloy may precipitate to form hydrogen bubbles, resulting in pores inside the casting, affecting the mechanical properties and electrical conductivity of the casting. Therefore, it is very important to control the hydrogen content of the alloy after smelting. It is mentioned in this application that the hydrogen content of the alloy after smelting should be less than 0.15ml / 100gAl, which can improve the quality of the casting, thereby helping to improve the conductivity and strength of the aluminum alloy material. The slag content should be less than 0.03mm 2 This stringent control standard of 0.1% / kgAl ensures the aluminum alloy has high purity and uniformity, and the lower slag content helps improve the overall quality of the finished product, enhancing its performance and reliability in structural and electrical applications.

[0163] Furthermore, in the present invention, the extrusion die temperature during extrusion of the aluminum alloy cast rod is 475-490°C, the extrusion barrel temperature is 455-470°C, the cast rod temperature is 510-525°C, the extruded billet temperature is 525-540°C, and online heat treatment is adopted after extrusion. The temperature of the aluminum alloy rod or profile after quenching is less than 180°C.

[0164] Setting the die temperature between 475°C and 490°C helps ensure good ductility during extrusion while preventing material damage or premature die wear caused by overheating. Appropriate die temperatures reduce extrusion forces and improve material flow, resulting in smooth, dimensionally precise aluminum alloy profiles. The extrusion barrel temperature is kept slightly below the die temperature, between 455°C and 470°C. This helps control the temperature gradient from the barrel to the die, ensuring temperature uniformity during extrusion and preventing localized overheating or cold hardening. The casting temperature is kept between 510°C and 525°C. This temperature range ensures sufficient ductility for easy forming during extrusion and facilitates flow and filling in the die. The extruded billet temperature is kept between 525°C and 540°C. Higher billet temperatures ensure a highly supersaturated solid solution after in-line quenching. Keeping the in-line heat treatment and post-quenching temperatures below 180°C locks in the material's microstructure, enhancing its mechanical strength and corrosion resistance. Rapid cooling of aluminum alloys to below 180°C helps form a supersaturated solid solution, which is a necessary condition for effective aging treatment.

[0165] Furthermore, the aging treatment of the present invention can select any one of T61, T63, T64, and T65 aging processes, wherein the T61 aging treatment is performed in a temperature range of 215° C. to 245° C. and lasts for 4 to 8 hours; the T63 aging treatment is performed in a temperature range of 200° C. to 230° C. and lasts for 8 to 12 hours; the T64 aging treatment is performed in a temperature range of 260° C. to 290° C. and lasts for 6 to 9 hours; and the T65 aging treatment is performed in a temperature range of 205° C. to 235° C. and lasts for 2 to 5 hours.

[0166] Artificial aging is a common heat treatment process in Al-Mg-Si aluminum alloys, designed to optimize the alloy's electrical conductivity and strength. By controlling the temperature and duration of the aging treatment, the characteristics of the precipitated phase in the alloy (such as size, shape, and distribution) can be adjusted, thereby optimizing performance. This application provides five different artificial aging treatment processes: T6, T61, T63, T64, and T65 aging treatments:

[0167] T6 aging treatment: Treatment is carried out at a temperature range of 190°C to 220°C for a duration of 8 to 12 hours. This aging process usually results in the formation of finer precipitates, which helps to improve the strength of the alloy, but may slightly sacrifice electrical conductivity.

[0168] T61 aging treatment: Treatment is carried out at a temperature range of 215°C to 245°C for a duration of 4 to 8 hours. This aging treatment process is designed to increase strength while maintaining good electrical conductivity.

[0169] T63 aging treatment: treatment is carried out at a temperature range of 200℃ to 230℃ and a duration of 8 to 12 hours. This aging process is similar to the T6 aging treatment, but may produce slightly different precipitation phase characteristics at different temperatures and times, and the electrical conductivity is higher than T6 aging.

[0170] T64 aging treatment: Treatment is carried out at a temperature range of 260°C to 290°C for a duration of 6 to 9 hours. This aging process is designed to produce larger precipitates, which helps maintain high conductivity, but the strength may not be as high as other aging treatments.

[0171] T65 aging treatment: treatment is carried out at a temperature range of 205°C to 235°C for a duration of 2 to 5 hours. This aging treatment process is designed to achieve rapid aging to quickly increase the strength and electrical conductivity of the alloy, and has high electrical conductivity.

[0172] Depending on the specific application needs and performance requirements, an appropriate aging treatment process can be selected to optimize the conductivity and strength of the alloy. Different aging treatment processes will result in different characteristics of the precipitated phase in the alloy, thus affecting the final properties of the alloy.

[0173] In general, the above four process routes have their own characteristics and applicable scenarios. By selecting the appropriate process route and parameters, the performance of aluminum core conductors can be optimized according to different application requirements.

[0174] It's worth noting that the four process routes described above can be selectively implemented based on actual usage and performance requirements. For example, some applications may prioritize improving conductivity at the expense of strength, or vice versa. Therefore, in actual production, the appropriate process route and aging treatment conditions can be flexibly selected based on specific needs to achieve the optimal performance balance.

[0175] The electrical conductivity and strength of the aluminum alloy material prepared by the above steps reach a predetermined range. This embodiment uses the synergistic effect of composition optimization design, casting and rolling, extrusion, solution treatment, cold working treatment and artificial aging treatment through the above process to improve the electrical conductivity and strength of the aluminum alloy. It effectively solves the contradiction between the electrical conductivity and strength of traditional aluminum alloys. The preparation process route of the present application has a short process, a fast production cycle, energy saving and time saving, and obvious economic benefits. Using the process of the present application, a high-conductivity aluminum alloy wiring harness material can be prepared. The material has excellent electrical conductivity and good strength characteristics, which meet its application needs in the fields of new energy vehicles, photovoltaic solar panels, battery energy storage systems, wind power generation devices, etc.

[0176] The features and performance of the present invention are further described in detail below with reference to the embodiments. Example

[0177] This embodiment provides an aluminum alloy wire harness with a single solid aluminum alloy conductor, which has a circular cross-sectional shape and a cross-sectional area of ​​150 mm. 2 The preparation method of the single solid aluminum alloy conductor is shown in Figure 8 .

[0178] S1 prepares raw materials according to the alloy composition: the concentration of alloy elements is Si 0.45%, Mg 0.55%, Cu 0.002%, Mn 0.002%, Cr 0.001%, Zn 0.005%, Ti 0.003%, Fe 0.05%;

[0179] S2 heats the aluminum ingot to melt at 735℃ and adds alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities, with hydrogen content of 0.10ml / 100gAl and slag content of 0.02mm 2 / kgAl;

[0180] S3 casts the aluminum alloy melt into aluminum alloy round casting rods;

[0181] S4 performs homogenization heat treatment on aluminum alloy round cast bars at 565℃;

[0182] S5 extrudes the aluminum alloy cast rod into aluminum alloy round bar, with the die temperature being 475°C, the extrusion barrel temperature being 460°C, the cast rod temperature being 520°C, and the extrusion billet temperature being 530°C;

[0183] S6 performs online solution quenching treatment on the aluminum alloy bar. After quenching, the temperature of the aluminum alloy bar or profile is 160℃;

[0184] S7 performs stretching and straightening treatment;

[0185] S8 is subjected to aging treatment, and T64 aging treatment is used to perform the treatment at a temperature range of 270°C for a duration of 8 hours.

[0186] The microstructure of the solid aluminum alloy conductor obtained in this embodiment was analyzed. Figure 10 , Figure 1 Intracrystalline edges can be observed <001> Al Needle-shaped β" phases precipitated. These needle-shaped precipitates had a diameter of approximately 5 nm and a length of less than 200 nm. The figure also shows the presence of a small number of dislocations within the crystal, with the dislocations surrounding the needle-shaped β" phase attached to the crystals. This indicates that the presence of dislocations promotes the precipitation of the β" phase. This example achieves a balance between high conductivity and excellent strength through precise control of the alloy composition and heat treatment process.

[0187] The test data of Example 1 are shown in Table 1. Example

[0188] This embodiment provides a stranded aluminum alloy wire harness with a rectangular cross-section and a cross-sectional area of ​​180 mm. 2 , its preparation method refers to Figure 7 :

[0189] S1 prepares raw materials according to the alloy composition: the concentration of alloy elements is Si 0.4%, Mg 0.5%, Cu 0.002%, Mn 0.001%, Cr 0.001%, Zn 0.005%, Ti 0.003%, Fe 0.05%;

[0190] S2 heats the aluminum ingot to melt at 750℃ and adds alloying elements in sequence; after melting, it is fully stirred and refined to remove gas and impurities to obtain a pure aluminum alloy melt with a hydrogen content of 0.10ml / 100gAl and a slag content of 0.02mm 2 / kgAl;

[0191] S3 continuously casts and rolls the aluminum alloy melt into aluminum alloy round rods;

[0192] S4: Aluminum alloy round rods are subjected to solution quenching treatment at 540°C and water cooling;

[0193] S5 draws the processed aluminum alloy round rod into aluminum alloy wire;

[0194] S6 is subjected to aging treatment, using T61 aging treatment at a temperature range of 225°C for 6 hours;

[0195] The test data of Example 2 is shown in Table 1. Example

[0196] This embodiment provides an aluminum alloy wire harness with a single solid aluminum alloy conductor, which has a rectangular cross-sectional shape and a cross-sectional area of ​​80 mm. 2 The preparation method is the same as that of Example 1 except that the alloy composition is different from that of Example 1 and the shape of the extrusion die is rectangular.

[0197] The concentrations of alloying elements are Si 0.3%, Mg 0.4%, Cu 0.001%, Mn 0.001%, Cr 0.001%, Zn 0.005%, Ti 0.003%, and Fe 0.08%;

[0198] The test data of Example 3 are shown in Table 1. Example

[0199] This embodiment provides an aluminum alloy wire harness with a single solid aluminum alloy conductor, the cross-sectional shape of which is a rounded rectangle with a cross-sectional area of ​​65mm 2 The preparation method is the same as that of Example 1 except that the alloy composition is different from that of Example 1 and the shape of the extrusion die is rectangular.

[0200] Alloy composition: The concentration of elements is Si 0.4%, Mg 0.55%, Cu 0.005%, Mn 0.001%, Cr 0.002%, Zn 0.005%, Ti 0.001%, Fe 0.05%;

[0201] The test data of Example 4 are shown in Table 1. Example

[0202] This embodiment provides an aluminum alloy wire harness with a single solid aluminum alloy conductor, the cross-sectional shape of which is a circle and the cross-sectional area is 80mm. 2 The preparation method is the same as that of Example 1 except that the alloy composition is different from that of Example 1 and the shape of the extrusion die is rectangular.

[0203] Alloy composition: The concentration of elements is Si 0.45%, Mg 0.55%, Cu 0.002%, Mn 0.001%, Cr 0.001%, Zn 0.003%, Ti 0.001%, Fe 0.06%;

[0204] The test data of Example 5 are shown in Table 1. Example

[0205] This embodiment provides an aluminum alloy wire harness with an aluminum alloy stranded wire having a circular cross-sectional shape and a cross-sectional area of ​​130 mm. 2 , its preparation method refers to Figure 9 .

[0206] S1 prepares raw materials according to the alloy composition, wherein the concentration of alloy elements is Si 0.45%, Mg 0.55%, Cu 0.002%, Mn 0.001%, Cr 0.001%, Zn 0.005%, Ti 0.003%, Fe 0.05%;

[0207] S2 heats the aluminum ingot to melt at 745℃ and adds alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities, with hydrogen content of 0.10ml / 100gAl and slag content of 0.02mm 2 / kgAl;

[0208] S3 casts the aluminum alloy melt into aluminum alloy round casting rods;

[0209] S4 performs homogenization heat treatment on aluminum alloy round cast bars at 560°C;

[0210] S5 extrude the aluminum alloy cast rod into aluminum alloy bar;

[0211] S6 performs off-line solution quenching treatment on aluminum alloy bars or profiles;

[0212] S7 performs stretching and straightening treatment;

[0213] S8 draws the processed aluminum alloy rod into aluminum alloy wire;

[0214] S9 is subjected to aging treatment, and T63 aging treatment is used to perform the treatment at a temperature range of 210°C for a duration of 9 hours.

[0215] The test data of Example 6 are shown in Table 1. Example

[0216] This embodiment provides an aluminum alloy wire harness with a single solid aluminum alloy conductor, which has a circular cross-sectional shape and a cross-sectional area of ​​150 mm. 2 , its preparation method refers to Figure 6 .

[0217] S1 prepares raw materials according to the alloy composition, wherein the concentration of alloy elements is Si 0.35%, Mg 0.45%, Cu 0.002%, Mn 0.001%, Cr 0.001%, Zn 0.002%, Ti 0.003%, Fe 0.06%;

[0218] S2: Melt the aluminum ingot at 725℃ and add alloying elements in sequence; after melting, stir and refine thoroughly to remove gas and impurities to obtain a pure aluminum alloy melt with a hydrogen content of 0.10ml / 100gAl and a slag content of 0.02mm 2 / kgAl;

[0219] S3 continuously casts and rolls the aluminum alloy melt into aluminum alloy round rods;

[0220] S4: Aluminum alloy round rods are solution treated at 540°C and water cooled;

[0221] S5 performs stretching and straightening treatment;

[0222] S6 is subjected to aging treatment, and T65 aging treatment is used to perform the treatment in the temperature range of 225°C for a duration of 5 hours.

[0223] The test data of Example 7 is shown in Table 1.

[0224] Table 1: Example test data.

[0225] Example Conductivity (%IACS) Tensile strength (MPa) Elongation (%) Example 1 59.6 255.4 16.8 Example 2 57.5 231.0 14.2 Example 3 59.0 258.2 15.4 Example 4 59.2 246.1 16.3 Example 5 59.8 240.6 17.8 Example 6 58.5 259.7 14.5 Example 7 57.8 234.3 14.8

[0226] Comparative Example 1:

[0227] 1) Alloy material preparation: Alloy composition: Si 0.5%, Mg 0.7%, Cu 0.02%, Mn 0.03%, Cr 0.05%, Zn0.005%, Ti 0.003%, Fe 0.1%

[0228] 2) Melting and casting: The alloy raw materials are directly cast into ingots after melting, and the hydrogen content of the ingots is not specially controlled.

[0229] 3) Homogenization heat treatment: Homogenization heat treatment is carried out at 530°C for 6 hours.

[0230] 4) Deformation treatment: Use traditional extrusion process and set the extrusion ratio to 40.

[0231] 5) Solution heat treatment: Solution treatment is carried out at 535℃ and the holding time is 2 hours.

[0232] 6) T6 aging treatment: Heat the solution treated aluminum to 190°C, keep it warm for 6 hours, and then air cool it to room temperature.

[0233] Testing revealed that the aluminum alloy prepared in the comparative example had an electrical conductivity of 55.5% IACS, significantly lower than the optimized aluminum alloy in the present invention. Its tensile strength was 215 MPa, and its elongation was 12%, indicating inferior overall performance compared to the present invention.

[0234] Comparative Example 2:

[0235] The preparation method and performance of conductive aluminum alloys refer to the standard GB / T 3954-2022 "Electrical Round Aluminum Rod".

[0236] Comparative Example 3:

[0237] The preparation method and performance of conductive aluminum alloys refer to the standard GB / T 27676-2011 "Aluminum and aluminum alloy tubular conductors".

[0238] By comparing the above embodiments with the comparative examples, it can be found that the aluminum alloy wire harness conductor material provided in the present application exhibits excellent electrical conductivity and mechanical properties under different preparation conditions, and the comprehensive performance of electrical conductivity and strength is higher than that of the comparative example.

[0239] This result demonstrates that the alloy composition, heat treatment process, and process route of this application significantly influence the microstructure and properties of the aluminum alloy. The preparation method of this application offers advantages such as a simple process flow, high production efficiency, energy conservation, and environmental protection. The resulting aluminum alloy material has broad application prospects, particularly in electrical connectors for new energy vehicles, conductive frames for photovoltaic solar panels, conductive connectors for battery energy storage systems, and conductive components for wind turbines.

[0240] It should be noted that, unless there is a conflict, the features in the embodiments of this application may be combined with each other. The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. For those skilled in the art, this application may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.

Claims

1. An aluminum alloy wire harness, characterized in that: The invention comprises an aluminum alloy wiring harness mother body and an end connector; the wiring harness mother body comprises an aluminum core conductor, an insulating layer, a shielding layer and a protective layer arranged in sequence from the inside to the outside; the end connector is selected from any one of a copper nose, a copper silver-plated nose or a nose pressed from one side of the aluminum core conductor, and the end connector is arranged at the end of the aluminum core conductor to achieve connection with other circuits or equipment; the aluminum core conductor is a single solid aluminum alloy conductor or an aluminum alloy stranded wire, and has any one of a circular, rectangular, rounded rectangular and unitary circular cross-sectional shape, and a cross-sectional area of ​​100-200 mm²; the aluminum core conductor is an Al-Mg-Si alloy, and its composition and ratio are Si 0.3-0.45%, Mg 0.40-0.55%, Cu<0.01%, Mn<0.005%, Cr<0.005%, Zn<0.01%, Ti<0.005%, Fe<0.1%, and other single elements<0.005%; the aluminum core conductor has a tensile strength greater than 230 MPa, a yield strength greater than 200 MPa, an elongation greater than 15%, an electrical conductivity greater than 57.5% IACS, and a thermal expansion coefficient less than or equal to 22×10 -6 / ℃; the insulating layer is a composite of PTFE and rubber solid solution material, which is co-extruded with the aluminum core conductor; the shielding layer is an aluminum drawing tube, which is fastened to the insulating layer by mechanical expansion and contraction technology, with a wall thickness of 2-5mm and adopts 8 series alloy, whose composition and proportion are: Si<0.1%, Fe 0.3-0.6%, Cu<0.05%, Mn0.8-1.2%, Mg<0.01%, Cr<0.02%, Ni<0.03%, Zn<0.02%, Ti<0.04%, and other single elements<0.005%; the protective layer is a mesh rubber material, which is sleeved on the outside of the shielding layer.

2. The aluminum alloy wire harness according to claim 1, characterized in that: The aluminum core conductor has a Mg / Si mass ratio of 1.1-1.3, and Mn+Ti+Cr+Zn≤0.02%.

3. The aluminum alloy wire harness according to claim 1, characterized in that: The aluminum core conductor is heat treated, and the heat treatment state is any one of T61, T63, T64, and T65; in the microstructure of the aluminum core conductor, a second phase exists in the aluminum matrix, and the second phase is a β" phase, and the number density of the β" phase is not less than 0.8×10 23 per cubic meter, with a volume fraction of not less than 1.5%; in the structure of the aluminum core conductor, the excess Mg content is not higher than 0.07%, and the excess Si content is not higher than 0.05%.

4. The aluminum alloy wire harness according to claim 1, characterized in that When the aluminum core conductor is a single solid aluminum alloy conductor, its end connector is designed to press the two ends of the aluminum alloy conductor into ends of a specific shape; when the aluminum core conductor is an aluminum alloy stranded wire, the end connector is made of either a copper nose or a copper-plated silver nose, and is fixedly connected to the aluminum alloy stranded wire through ultrasonic welding technology to ensure connection reliability and electrical performance.

5. A method for preparing an aluminum alloy wire harness according to any one of claims 1 to 4, characterized in that: The steps include: (1) Preparation of aluminum core conductor; (2) Co-extruding the aluminum core conductor and the insulation layer; (3) Condensed aluminum shielding layer and insulation layer; (4) Preparing an end connector, including preparing one end of an aluminum core conductor into an end connector or welding one end of an aluminum core conductor to an existing end connector; or (5) bending the aluminum alloy wire harness into a fixed shape; (6) Put on the protective cover; (7) Install the end fixings.

6. The method for preparing an aluminum alloy wire harness according to claim 5, characterized in that The preparation of aluminum core conductors can be done by selecting any of the following process flows based on product performance requirements and manufacturing conditions: 1) A process flow suitable for preparing a single solid aluminum alloy conductor with medium strength and high conductivity, comprising the following steps: a. Prepare raw materials according to alloy composition; b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt; c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod; e. Solution treatment of aluminum alloy round rods at 520-540℃ and water cooling; i. Perform tensile straightening treatment; k. Carry out aging treatment; 2) A process flow suitable for preparing medium-strength, high-conductivity aluminum alloy stranded wire includes the following steps: a. Prepare raw materials according to alloy composition; b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities to obtain a pure aluminum alloy melt; c. continuously casting and rolling the aluminum alloy melt into an aluminum alloy round rod; e. Solution quenching treatment of aluminum alloy round rods at 520-540℃ and water cooling; j. The processed aluminum alloy round rod is drawn into aluminum alloy wire; k. Carry out aging treatment; 3) A process flow suitable for preparing a single solid aluminum alloy conductor with high strength and high conductivity, comprising the following steps: a. Prepare raw materials according to alloy composition; b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities; d. Casting the aluminum alloy melt into aluminum alloy round cast rods; f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃; g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles; h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles; i. Perform tensile straightening treatment; k. Carry out aging treatment; 4) A process flow suitable for preparing high-strength, high-conductivity aluminum alloy stranded wire includes the following steps: a. Prepare raw materials according to alloy composition; b. Melt the aluminum ingot at 720-750°C and add the alloying elements in sequence; after melting, stir thoroughly and refine to remove gas and impurities; d. Casting the aluminum alloy melt into aluminum alloy round cast rods; f. Perform homogenization heat treatment on the aluminum alloy round cast rod at 550-570℃; g. Extruding the aluminum alloy cast rod into aluminum alloy bars or profiles; h. Perform online solution quenching treatment or offline solution quenching treatment on aluminum alloy bars or profiles; j. Drawing the processed aluminum alloy bars or profiles into aluminum alloy wires; k. Carry out aging treatment.

7. The method for preparing an aluminum alloy wire harness according to claim 6, characterized in that The hydrogen content in the melt should be less than 0.15ml / 100gAl, and the slag content should be less than 0.03mm 2 / kgAl.

8. The method for preparing an aluminum alloy wire harness according to claim 6, characterized in that The extrusion die temperature during aluminum alloy casting rod extrusion is 475~490℃, the extrusion barrel temperature is 455~470℃, the casting rod temperature is 510~525℃, the extrusion billet temperature is 525~540℃, and online heat treatment is adopted after extrusion. The temperature of the aluminum alloy rod or profile after quenching is <180℃.

9. The method for preparing an aluminum alloy wire harness according to claim 6, characterized in that The aging treatment is any one of T61, T63, T64 and T65, wherein the T61 aging treatment is carried out at a temperature range of 215°C to 245°C and lasts for 4 to 8 hours; the T63 aging treatment is carried out at a temperature range of 200°C to 230°C and lasts for 8 to 12 hours; the T64 aging treatment is carried out at a temperature range of 260°C to 290°C and lasts for 6 to 9 hours; and the T65 aging treatment is carried out at a temperature range of 205°C to 235°C and lasts for 2 to 5 hours.

10. The use of the aluminum alloy wire harness according to claim 1, characterized in that: The aluminum alloy wiring harness is used in the fields of electrical connection components of new energy vehicles, conductive frames of photovoltaic solar panels, conductive connectors of battery energy storage systems, and conductive components of wind power generation devices.

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