A high-conductivity aluminum alloy material and its preparation method

Abstract

This invention provides an Al-Mg-Si based high-conductivity aluminum alloy material and its preparation method. The microstructure of this aluminum alloy is characterized by: fine and uniform recrystallized grains accounting for 30% to 50%, with a size less than 5 μm; the grains exhibit a... <111> and <100> Orientation; along the grain interior <001> Al and <111> Al Needle-shaped β″ precipitates are formed in the direction of precipitation, with a diameter of less than 10 nm and a length of less than 100 nm; <001> Al Spherical β′ and / or β precipitates are formed at grain boundaries; the intragranular dislocation density is less than 2.5 × 10⁻⁶. 14 m ‑2 This material possesses an electrical conductivity of 58% to 60% IACS, making it suitable for electrical connections in new energy vehicles, conductive frames for photovoltaic cells, connectors for battery energy storage systems, and conductive components for wind power generation. This technology achieves a balance between high conductivity and excellent strength through a simple process and its energy-saving and environmentally friendly characteristics, making it suitable for a wide range of applications and realizing the goal of replacing copper with aluminum.

Description

Technical Field

[0001] This application relates to the field of aluminum alloy material processing technology, and more specifically, to an Al-Mg-Si system high electrical conductivity aluminum alloy material and its preparation method. Background Technology

[0002] With the rapid development of green energy industries such as new energy vehicles and solar photovoltaics, the demand for high-performance conductive materials is also increasing. While copper, as a traditional conductive material, possesses excellent conductivity, its limited resources and high price have led to the search for alternatives. Aluminum alloys, due to their lightweight, low cost, and good conductivity, are gradually becoming an ideal replacement for copper. In the new energy vehicle sector, the rapid popularization of electric vehicles has placed higher demands on the conductive materials of key components such as battery connectors and motor windings. Simultaneously, in the solar photovoltaic industry, the continuous expansion of installed capacity is driving up the demand for conductive frames and connecting wires. These applications place high demands on the conductivity and mechanical strength of conductive materials.

[0003] However, while traditional Al-Mg-Si aluminum alloys possess a certain degree of electrical conductivity, further improvements in conductivity typically require the addition of alloying elements and heat treatment. A key challenge in this process is balancing the alloy's conductivity and mechanical strength. Past research has primarily focused on grain refinement and heat treatment processes, but these often fail to simultaneously meet the demands for high conductivity and high strength.

[0004] This invention proposes a high-conductivity aluminum alloy material and its preparation method. By precisely controlling the microstructure and phase characteristics of the alloy, an optimized balance between conductivity and strength is achieved. This material not only possesses higher conductivity than traditional aluminum alloys but also maintains good mechanical properties, enabling it to meet the demands of high-performance conductive materials in fields such as new energy vehicles and solar photovoltaics. The technology of this invention enables the lightweighting and cost reduction of conductive materials, providing strong material support for the development of the green energy industry.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this application is to provide a high-conductivity aluminum alloy material, its preparation method, and its application.

[0007] This invention is implemented as follows:

[0008] In a first aspect, the present invention provides a highly conductive aluminum alloy material, characterized in that the aluminum alloy belongs to the Al-Mg-Si system, and its microstructure has the following characteristics: its microstructure contains fine and uniform recrystallized grains and non-recrystallized grains extending along the deformation direction, wherein the proportion of recrystallized grains is 30% to 50%, and the size of the recrystallized grains is less than 5 μm; the grains mainly exhibit a shape along the deformation direction. <111> Orientation and perpendicular to the deformation direction <100> Orientation; within the grain, along <001> Al and <111> Al Needle-shaped β″ precipitates precipitate in three equivalent directions, with a diameter less than 10 nm and a length less than 100 nm; <001> Al Spherical β′ and / or β precipitates are formed at grain boundaries; the intragranular dislocation density is less than 2.5 × 10⁻⁶. 14 m -2 The total resistivity of the aluminum alloy ( ρ The total (total) is less than 29.5 nΩm, and its conductivity is in the range of 58% to 60% IACS.

[0009] Secondly, the present invention provides a method for preparing a high-conductivity aluminum alloy material, comprising the following steps: providing alloy raw materials, wherein the concentration of alloying elements meets a specific range; melting and casting the alloy raw materials to form a casting; subjecting the casting to homogenization heat treatment to obtain a homogeneous casting; subjecting the homogeneous casting to pressure processing to obtain aluminum material; subjecting the aluminum material to solution treatment to obtain solution-treated aluminum material; optionally, subjecting the solution-treated aluminum material to pre-artificial aging treatment; optionally, subjecting the solution-treated aluminum material to cold working treatment; and subjecting the solution-treated aluminum material, or the aluminum material that has undergone solution treatment followed by pre-artificial aging treatment, or the aluminum material that has undergone solution treatment followed by cold working treatment, or the aluminum material that has undergone solution treatment, pre-artificial aging treatment, and cold working treatment, to artificial aging treatment.

[0010] Thirdly, the present invention also provides applications of the high conductivity aluminum alloy material described in the above embodiments in 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.

[0011] The advantages of this invention compared to existing technologies are: it provides an Al-Mg-Si system high-conductivity aluminum alloy material with high electrical conductivity and excellent mechanical strength. By optimizing the alloy's microstructure and phase characteristics, it achieves a reduction in resistivity and an improvement in conductivity, thereby meeting the demand for high-performance conductive materials in fields such as new energy vehicles and solar photovoltaics. Simultaneously, this technology, with its simple process flow and energy-saving and environmentally friendly characteristics, achieves lightweighting and cost reduction of conductive materials, providing strong material support for the development of the green energy industry. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a TEM image of a grain boundary structure illustrated in one embodiment of this application.

[0014] Figure 2 As illustrated in one embodiment of this application <001> Al TEM image of the intracrystalline structure. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0016] The technical solution of this application will be clearly and completely described below.

[0017] This invention provides an Al-Mg-Si conductive aluminum alloy, the microstructure of which has the following characteristics:

[0018] Its microstructure consists of fine, uniform recrystallized grains and non-recrystallized grains extending along the deformation direction, with recrystallized grains accounting for 30% to 50% and their size being less than 5 μm. This structure is beneficial for improving the material's electrical conductivity because the fine recrystallized grains reduce the obstruction of electron conduction by grain boundary scattering. Simultaneously, the dislocations contained in a certain proportion of the non-recrystallized grains promote the precipitation of precipitates, which on the one hand strengthen the material's strength, and on the other hand improve electrical conductivity due to the reduction in solute atoms.

[0019] The grains mainly exhibit a shape along the deformation direction. <111> Orientation and perpendicular to the deformation direction <100> Orientation. In Al-Mg-Si aluminum alloys (FCC structure). <111> The direction of closest packing is the most densely packed direction, where electrons have a stronger conductivity. Therefore, when grains exhibit this orientation along the deformation direction (usually the stretching or compressing direction)... <111> Orientation can promote electron conduction along that direction, thereby improving the material's electrical conductivity. Similarly, <100> Direction is also an important direction of transmission, although it is not as important as... <111> Directional density. When grains are perpendicular to the deformation direction. <100> When oriented, a good electronic conduction path can be provided in a plane perpendicular to the main conduction direction, thereby forming a more uniform conductive network throughout the material.

[0020] Inside the grain, along <001> Al and <111> Al Needle-shaped β″ precipitates are formed in three equivalent directions, with diameters less than 10 nm and lengths less than 100 nm. Generally, to reduce electron scattering, the size and uniform distribution of the precipitate phase should be kept as small as possible. Fine β″ precipitates can provide sufficient strength enhancement while having minimal impact on conductivity. This application optimizes the size and distribution of the precipitate phase by precisely controlling the temperature and time of the aging treatment, thereby improving conductivity.

[0021] In Al-Mg-Si alloys, the β″ precipitate is considered the ideal precipitate phase because it can enhance strength while having a relatively small impact on electrical conductivity. The β″ precipitate is a metastable phase with a small size and high relative electrical conductivity. In contrast, while larger β′ or β phases can provide higher strength, they also have a greater negative impact on electrical conductivity. Therefore, while pursuing both strength and high electrical conductivity, emphasis should be placed on promoting the formation of the β″ precipitate, while avoiding the formation of β′ or β phases caused by excessive aging.

[0022] exist <001> Al Spherical β′ and / or β precipitates form at the grain boundaries. <001> Spherical β′ and / or β precipitates form at the grain boundaries of Al grains. These spherical precipitates hinder grain boundary movement, enhancing grain boundary strengthening and thus improving the material's creep resistance and strength. The formation of grain boundary precipitates consumes solute atoms (such as Mg and Si) in the crystal lattice, reducing their scattering effect on electron conduction and improving the material's electrical conductivity. Since the spherical precipitates are located at grain boundaries, their impact on the overall conductivity of the material is relatively small, as grain boundaries themselves are regions that impede electron conduction. This invention achieves a good balance between precipitates and electrical conductivity by optimizing alloy composition and heat treatment processes.

[0023] The intracrystalline dislocation density is less than 2.5 × 10⁻⁶.14 m -2 A lower dislocation density is beneficial for reducing electron scattering, thereby improving electrical conductivity. While moderate cold working can increase dislocation density and promote the formation of precipitated phases, excessive cold working may lead to dislocation density accumulation, thus reducing conductivity. Therefore, a balance needs to be struck between cold working and aging treatment to optimize the effect of microstructure on conductivity. The dislocation density controlled in this invention enables the alloy to possess high electrical conductivity.

[0024] The total resistivity of the aluminum alloy in this application ( ρ The total conductivity is less than 29.5 nΩm, and its conductivity is in the range of 58% to 60% IACS. This indicates that the material has good electrical conductivity and is more suitable for use as a conductive material in a variety of applications.

[0025] In the microstructure of highly conductive aluminum alloys, the characteristics of grain boundaries and intragranular structures can be clearly observed using transmission electron microscopy (TEM): Figure 1 In the sample, approximately spherical β′ and β phases were observed at the grain boundaries, with the β phase measuring approximately 80 nm and the β′ phase approximately 30 nm in size. The presence of these spherical precipitates helps to hinder grain boundary movement, enhancing the grain boundary strengthening effect and thus improving the overall strength of the material. Simultaneously, these precipitates can also reduce the number of solute atoms in the lattice, decreasing the scattering effect of solute atoms on electron conduction and thus improving the material's electrical conductivity.

[0026] Figure 2 In the middle, the inner edge of the crystal can be seen <001> Al Needle-shaped β″ phases were precipitated. These needle-shaped precipitates are approximately 5 nm in diameter and less than 90 nm in length. The figure also shows a small number of dislocations within the crystal, with the needle-shaped β″ phases attached to the surrounding area, indicating that the presence of dislocations promotes the precipitation of the β″ phase. This invention achieves the formation of intracrystalline β″ phases through precise control of alloy composition and heat treatment processes. This helps improve the strength of the material, and due to its small size, its electron scattering effect is relatively weak, thus having a smaller impact on conductivity, achieving a balance between high conductivity and excellent strength.

[0027] Furthermore, the total resistivity described in this application ( ρ According to Matthisen's rule, total is composed of the parent metal ( ρ base), dislocation ( ρ disl), grain boundary ( ρ GB ) and alloy solute atoms ( ρ ss) and precipitate phase ( ρThe sum of contributions from precip, without considering vacancy concentration (which will not exceed 0.001%), satisfies the following relationship:

[0028] ρ total= ρ base+ L disl Δρ disl+ S GB Δρ GB +∑ ρ alloy ci , αi )+∑ ρ precip( f par j , sj , DJ )

[0029] in:

[0030] ρ base is the resistivity of pure aluminum, with a value of 26.55 nΩm;

[0031] Δρ disl is the resistivity increase caused by dislocations due to pressure deformation, expressed as a unit dislocation. Δρ The value of disl is 2.7 × 10. −25 Ωm 3 , ρ disl at solid solution temperature ( T sol The resistivity is relatively low within the range of 520-535℃. Dislocations are linear defects in crystal structures that significantly affect the resistivity of materials. The presence of dislocations increases the resistivity of materials because they scatter electrons passing through the crystal, thereby reducing electron mobility and the conductivity of the material. Δρ disl represents the increase in resistivity per unit dislocation. For Al-Mg-Si aluminum alloys, this value is typically taken as 2.7 × 10⁻⁶. −25 Ωm 3 .

[0032] Within the solution treatment temperature range of 520-535℃, solute atoms (such as Mg and Si) in Al-Mg-Si aluminum alloys enter the aluminum lattice, forming a supersaturated solid solution. During this process, due to the high temperature, existing dislocations in the material may annihilate or rearrange, leading to a decrease in dislocation density. Therefore, within this temperature range, the resistivity increase caused by dislocations (…) ρ The relatively small disl value helps maintain high conductivity.

[0033] ρ GB represents resistivity with increasing grain size, per grain boundary. Δρ GB The value is 2.6 × 10 −16 Ωm 2 Grain size has a significant impact on the resistivity of a material. Smaller grain size means a greater number of grain boundaries, which are scattering centers for electron conduction. Therefore, as grain size decreases, the number of grain boundaries increases, and electrons encounter more scattering as they pass through the material, leading to an increase in resistivity. This application, by adjusting a certain recrystallization ratio, is essentially a method for controlling grain size. (Unit grain boundary) Δρ GB The value of reflects the contribution of grain boundaries to resistivity. For Al-Mg-Si aluminum alloys, the value per unit grain boundary is... Δρ GB The value is usually 2.6 × 10. −16 Ωm 2 Therefore, to achieve higher conductivity, it is necessary to minimize the scattering effect of grain boundaries on electron conduction. This can be achieved by controlling the grain size, i.e., by increasing the grain size through appropriate heat treatment processes, thereby reducing the number of grain boundaries, decreasing the increase in resistivity caused by grain boundaries, and improving the conductivity of the material.

[0034] ∑ ρ alloy ci , αi The increase in resistivity represents the increase of the alloying element, taking into account the element's properties. ci The concentration and corresponding resistivity coefficient αi Concentration per unit (at.%) ρ ss is approximately 0.4-0.9×10 -8 Ωm, where ci The range is: Si 0.3-0.5%, Mg 0.35-0.65%, Cu <0.01%, Mn <0.01%, Cr <0.01%, Zn <0.01%, Ti <0.005%, Fe <0.1%, B 0~ x %, with other individual elements <0.005%. In Al-Mg-Si aluminum alloys, the addition of alloying elements is intended to improve material properties, but it also affects the material's resistivity. ∑ ρ alloy ci , αi ) represents the increase in resistivity caused by alloying elements, where ci It is the concentration of alloying elements. αi This is the contribution factor of the element to resistivity. It represents the increase in resistivity per unit concentration (at.%). ρ SS is usually between 0.4 and 0.9 × 10. -8Within the range of Ωm. The effects of different alloying elements' concentrations and their influence on resistivity are as follows:

[0035] Silicon (Si) 0.3-0.5%: Silicon is one of the main alloying elements in Al-Mg-Si aluminum alloys. It forms the Mg2Si reinforcing phase with magnesium, improving the strength of the material. The amount of silicon added is usually controlled at 0.3-0.5% to ensure sufficient strengthening effect without excessively increasing resistivity.

[0036] Magnesium (Mg) 0.35-0.65%: Magnesium is another important alloying element, and it also participates in the formation of the Mg2Si strengthening phase. The amount of magnesium added is usually controlled at 0.35-0.65% to achieve good strengthening effect and appropriate electrical conductivity.

[0037] An ideal Mg / Si ratio ensures sufficient formation of the Mg₂Si reinforcing phase to improve strength, while avoiding excessive free Si or Mg atoms, which can increase resistivity and decrease conductivity. Generally, a Mg / Si ratio between 1.0 and 1.3 is considered optimal, providing a good balance between strength and conductivity. If the Mg / Si ratio is too high, there may be too many free Mg atoms, leading to increased resistivity; if the ratio is too low, there may be too many free Si atoms, which will also affect conductivity.

[0038] Copper (Cu) <0.01%: Copper is an element that significantly increases resistivity. Therefore, in aluminum alloys that require high conductivity, the copper content should be as low as possible, usually controlled below 0.01%.

[0039] Manganese (Mn), chromium (Cr), zinc (Zn), titanium (Ti) <0.01%, iron (Fe) <0.1%: These elements usually exist as impurities, and their content should be controlled as low as possible to reduce the negative impact on conductivity.

[0040] Boron (B) 0~x%: The addition of boron can refine the grains and improve the processing performance of the material. In addition, the amount of boron added is related to the total amount of Mn, Cr, and Ti, and is used to neutralize the negative effects of these elements.

[0041] By controlling the content and proportion of these alloying elements, the microstructure and properties of Al-Mg-Si aluminum alloys can be optimized, achieving a balance between high electrical conductivity and good mechanical properties.

[0042] ∑ ρ precip( f par j , sj , DJ The ) represents the increase in resistivity due to the precipitated phase, taking into account the precipitated phase.j volume fraction f par j ,size sj and density DJ precipitate phase j The electrical conductivity and strength of the alloy can be optimized by controlling the artificial aging treatment state using T6, T61, T63, T64, or T65. f par j This indicates the volume percentage of the precipitated phase in the alloy. A higher volume fraction means more precipitated phase, which may lead to a greater increase in resistivity. sj This indicates the size of the precipitate phase. A suitable precipitate phase may cause greater scattering of electron conduction, thereby increasing resistivity. DJ This indicates the distribution density of the precipitated phase in the alloy. A higher density means that the precipitated phases are closer together, which may lead to a stronger electron scattering effect.

[0043] Artificial aging treatment can control these characteristics of precipitated phases, thereby optimizing alloy properties. Different aging treatment states (T6, T61, T63, T64, T65) will result in different precipitated phase characteristics, so the appropriate aging treatment process needs to be selected according to the specific application and performance requirements. For example, T6 aging treatment usually results in finer precipitated phases, which helps to improve strength, but may slightly sacrifice electrical conductivity; while T64 aging treatment may result in larger precipitated phases, which helps to maintain higher electrical conductivity, but the strength may not be as high as that of T6 aging treatment.

[0044] In summary, by controlling the volume fraction, size, and density of the precipitated phase, the electrical conductivity can be optimized while maintaining the alloy's strength, thus achieving the design goal of highly conductive aluminum alloys.

[0045] Furthermore, in this application, when the total amount of Mn, Cr, and Ti in the aluminum alloy is less than 0.015%, B is not added; when the total amount exceeds 0.015%, the amount of B added is... x The percentage is calculated based on 1.25 to 1.5 times the stoichiometric coefficient of B required to form borides from Mn, Cr, Ti and B.

[0046] In Al-Mg-Si aluminum alloys, trace elements such as manganese (Mn), chromium (Cr), and titanium (Ti) are typically added to improve alloy properties, such as strength and corrosion resistance. However, excessive presence of these elements in the alloy can lead to the formation of undesirable phases, thereby reducing the alloy's electrical conductivity. To suppress the formation of these undesirable phases, boron (B) can be added to form stable borides with Mn, Cr, and Ti, thereby reducing the concentration of these elements in the alloy matrix and improving the alloy's electrical conductivity.

[0047] This application states that when the total content of Mn, Cr, and Ti in the alloy is less than 0.015%, the addition of boron (B) is unnecessary because the content of these elements is already low enough that it is unlikely to negatively affect the alloy's electrical conductivity. However, when the total content of Mn, Cr, and Ti exceeds 0.015%, B needs to be added to form borides with these elements to reduce their concentration in the alloy matrix. The amount of B added (x%) is calculated based on the stoichiometric coefficient of B required to form borides with Mn, Cr, and Ti. Typically, the amount of B added is slightly higher than the theoretically calculated value by 1.25 to 1.5 times to ensure that Mn, Cr, and Ti can completely react with B to form borides, thereby minimizing the impact of these elements on the alloy's electrical conductivity. This method of adding B helps optimize the alloy's electrical conductivity while maintaining a balance of other properties.

[0048] Furthermore, the aluminum alloy of this application employs one of the following five artificial aging treatment processes to optimize the alloy's electrical conductivity and strength:

[0049] T6 aging treatment: The treatment is carried out in a temperature range of 190℃ to 220℃ for a duration of 8 to 12 hours;

[0050] T61 aging treatment: The treatment is carried out in the temperature range of 215℃ to 245℃ for a duration of 4 to 8 hours;

[0051] T63 aging treatment: The treatment is carried out in a temperature range of 200℃ to 230℃ for a duration of 8 to 12 hours;

[0052] T64 aging treatment: The treatment is carried out in a temperature range of 260℃ to 290℃ for a duration of 6 to 9 hours;

[0053] T65 aging treatment: The treatment is carried out in the temperature range of 205℃ to 235℃ for a duration of 2 to 5 hours.

[0054] Artificial aging is a commonly used heat treatment process in Al-Mg-Si aluminum alloys, aimed at optimizing the alloy's electrical conductivity and strength. By controlling the temperature and time of the aging treatment, the characteristics of precipitated phases in the alloy (such as size, shape, and distribution) can be adjusted, thereby achieving performance optimization. This application provides five different artificial aging treatment processes: T6, T61, T63, T64, and T65 aging treatments.

[0055] T6 aging treatment: The treatment is carried out at a temperature range of 190°C to 220°C for 8 to 12 hours. This aging process typically results in the formation of finer precipitates, which helps improve the strength of the alloy, but may slightly sacrifice electrical conductivity.

[0056] T61 aging treatment: The treatment is carried out at a temperature range of 215℃ to 245℃ for 4 to 8 hours. This aging treatment process aims to improve strength while maintaining good electrical conductivity.

[0057] T63 aging treatment: The treatment is carried out in the temperature range of 200℃ to 230℃ for 8 to 12 hours. This aging treatment process is similar to T6 aging treatment, but may produce slightly different precipitate phase characteristics at different temperatures and times, and the electrical conductivity is higher than that of T6 aging.

[0058] T64 aging treatment: The treatment is carried out at a temperature range of 260°C to 290°C for 6 to 9 hours. This aging treatment process aims to produce a larger precipitate phase, which helps maintain high electrical conductivity, but the strength may not be as high as other aging treatment processes.

[0059] T65 aging treatment: The treatment is carried out at a temperature range of 205℃ to 235℃ for 2 to 5 hours. This aging treatment process aims to achieve rapid aging to quickly improve the strength and electrical conductivity of the alloy, while maintaining high conductivity.

[0060] Depending on the specific application requirements and performance specifications, an appropriate aging treatment process can be selected to optimize the electrical conductivity and strength of the alloy. Different aging treatment processes will result in different characteristics of the precipitated phases in the alloy, thus affecting the final properties of the alloy.

[0061] Furthermore, the present invention also provides a method for preparing a highly conductive aluminum alloy material, which includes the following steps:

[0062] a) Provide alloy raw materials according to the alloy element ratios;

[0063] b) The alloy raw materials are melted and cast to form castings;

[0064] Ideally, the hydrogen content of the alloy after smelting should be less than 0.15 ml / 100 g Al.

[0065] Hydrogen content is a crucial parameter that needs to be controlled during the aluminum alloy smelting process. Aluminum alloys readily absorb hydrogen gas during melting, forming hydrogen solutes. When the alloy solidifies, the hydrogen dissolved in the aluminum alloy may precipitate, forming hydrogen bubbles. This can lead to porosity inside the casting, affecting its mechanical properties and electrical conductivity. Therefore, controlling the hydrogen content after alloy smelting is extremely important.

[0066] This application states that the hydrogen content after alloy melting should be less than 0.15 ml / 100g Al. This means that the volume of dissolved hydrogen in every 100g of aluminum alloy should not exceed 0.15 ml. By controlling the hydrogen content below this level, porosity inside the casting can be reduced, improving the quality of the casting and thus contributing to increased conductivity and strength of the aluminum alloy material.

[0067] c) Perform homogenization heat treatment on the castings to obtain homogeneous castings;

[0068] The homogenization heat treatment process involves treatment at a temperature range of 500°C to 550°C for a duration of 6 to 10 hours.

[0069] Homogenization heat treatment can redistribute alloying elements within castings, reducing segregation and releasing internal stress, thereby improving the homogeneity and plasticity of the castings. The homogenization heat treatment regime mentioned in this application involves treatment within a temperature range of 500°C to 550°C for 6 to 10 hours. This temperature range and time duration are optimized to effectively homogenize the castings while avoiding the adverse effects of over-heat treatment. Homogenization heat treatment yields homogeneous castings, laying a solid foundation for subsequent machining and performance optimization. This is of great significance for improving the electrical conductivity and strength of aluminum alloy materials.

[0070] d) The homogeneous casting is pressure processed to obtain aluminum material;

[0071] Pressure processing can be either extrusion or rolling. If extrusion deformation is used, the extrusion ratio is 20 to 80. If rolling deformation is used, the rolling deformation amount is 60% to 85%.

[0072] Extrusion is a process of forming aluminum material with a desired cross-sectional shape by extruding a homogeneous casting through a die under high pressure. The extrusion ratio refers to the ratio of the cross-sectional area of ​​the homogeneous casting before extrusion to the cross-sectional area of ​​the aluminum material after extrusion. In this application, the extrusion ratio is 20 to 80, meaning that the cross-sectional area of ​​the aluminum material after extrusion is 1 / 20 to 1 / 80 of the cross-sectional area of ​​the homogeneous casting before extrusion. A higher extrusion ratio helps refine the grain size, improving the mechanical properties and electrical conductivity of the aluminum material. Rolling is a processing method that reduces the thickness of a homogeneous casting by subjecting it to pressure between a pair of rotating rolls. The rolling deformation refers to the percentage change in the thickness of the aluminum material before and after rolling. In this application, the rolling deformation is 60% to 85%, meaning that the thickness of the aluminum material is reduced by 60% to 85% through rolling. A larger rolling deformation helps enhance the mechanical properties of the aluminum material while also improving its electrical conductivity. Through pressure processing, the aluminum alloy can be strengthened and its microstructure refined, thereby improving the electrical conductivity and strength of the aluminum alloy material. Choosing the appropriate extrusion ratio and rolling deformation is crucial for obtaining aluminum materials with excellent properties.

[0073] e) Perform a solution treatment on the aluminum material to obtain a solution-treated aluminum material;

[0074] Solution treatment is an important step in the heat treatment of aluminum alloys. Its purpose is to completely dissolve solute atoms (such as Mg, Si, etc.) in the alloy into the aluminum matrix to form a homogeneous solid solution. This process typically involves heating the aluminum to a certain temperature, holding it for a period of time, and then rapidly cooling it to "freeze" the distribution of solute atoms in the aluminum matrix.

[0075] In this application, the solution treatment temperature range is 520-535℃. This temperature range is specifically optimized based on the phase diagram and alloy composition of Al-Mg-Si aluminum alloys to ensure that solute atoms such as Mg and Si in the alloy can fully dissolve into the aluminum matrix without causing excessive grain growth or the formation of undesirable phases. Simultaneously, at this temperature, existing dislocations in the material may annihilate or rearrange, leading to a reduction in dislocation density and contributing to maintaining high electrical conductivity. The aluminum material after solution treatment possesses a uniform solid solution microstructure, which is crucial for subsequent aging treatment and optimization of aluminum alloy properties. Through solution treatment, the plasticity and processing properties of aluminum alloys can be improved, laying the foundation for achieving high electrical conductivity and good mechanical properties.

[0076] f) Optionally, the solution-treated aluminum material may undergo pre-artificial aging treatment;

[0077] Preferably, the pre-artificial aging treatment is carried out at a temperature range of 160°C to 180°C for a duration of 1 to 5 hours.

[0078] Pre-aging (also known as pre-hardening) is an optional heat treatment process performed on aluminum alloys after solution treatment and before final artificial aging. Its purpose is to induce fine second-phase particles, or Guinier-Preston (GP) zones, in the aluminum alloy. These particles can serve as a nucleation basis for more stable precipitated phases during subsequent aging, thereby improving the alloy's mechanical properties and electrical conductivity.

[0079] In Al-Mg-Si aluminum alloys, pre-artificial aging treatment typically involves heating the solution-treated aluminum to a relatively low temperature (160°C to 180°C in this application) and holding it for a period of time (1 to 5 hours in this application). This temperature range is specifically chosen to promote the formation of GP zones, which are tiny regions rich in solute atoms (such as Mg and Si) that are ordered within the aluminum matrix but have not yet formed stable precipitates. Pre-artificial aging treatment can form numerous small GP zones in the aluminum alloy. These GP zones can then act as nucleation sites for β″ precipitates during subsequent artificial aging, thereby accelerating precipitate formation and improving the alloy's strength. Simultaneously, due to the very small size of the GP zones, their impact on the electrical conductivity of the aluminum alloy is relatively small, thus maintaining high conductivity while improving strength. This makes pre-artificial aging treatment an effective means of optimizing the properties of Al-Mg-Si aluminum alloys. However, for this application, this step is not mandatory and can be selected based on actual needs.

[0080] g) Optionally, the solution-treated aluminum material may be subjected to cold working.

[0081] Cold working (such as cold rolling or cold drawing) is a machining process that can be performed on aluminum alloys after solution treatment. Its purpose is to change the microstructure and macroscopic shape of the aluminum material through plastic deformation in order to achieve specific mechanical properties, electrical conductivity and dimensional specifications.

[0082] During cold working, numerous dislocations are generated within the aluminum alloy. These dislocations can serve as nucleation sites for precipitated phases, thus accelerating the precipitation hardening process. Particularly when cold working is combined with pre-aging, the fine GP zones formed by the pre-aging process interact with the dislocations introduced by cold working, promoting faster and more uniform precipitated phase formation, thereby improving the alloy's strength and conductivity. Although cold working increases the dislocation density in the aluminum alloy, thus increasing resistivity, this effect is generally smaller compared to the positive impact of precipitated phases on conductivity. Therefore, by appropriately controlling the degree of cold working, it is possible to maintain high conductivity while improving strength.

[0083] Furthermore, cold working can also bring aluminum alloys to the required dimensions and shapes, such as wires of different diameters, thereby expanding their applications in electrical connection components, high-voltage wiring harnesses, and other fields. Therefore, cold working is one of the important means to optimize the properties of Al-Mg-Si aluminum alloys and meet specific application requirements. However, for this application, this step is not mandatory and can be selected according to actual needs.

[0084] h) Perform artificial aging treatment on aluminum materials that have undergone solution treatment, or aluminum materials that have undergone solution treatment followed by pre-artificial aging treatment, or aluminum materials that have undergone solution treatment followed by cold working, or aluminum materials that have undergone solution treatment, pre-artificial aging treatment, and cold working treatment.

[0085] Artificial aging is the final key step in the heat treatment of Al-Mg-Si aluminum alloys, aiming to optimize the alloy's electrical conductivity and strength. In this step, artificial aging can be selectively performed depending on different process routes and practical application requirements.

[0086] i) Artificial aging treatment of aluminum materials that have only undergone solution treatment: This process is suitable for applications that require a balance between strength and conductivity. Artificial aging treatment can promote the formation of precipitated phases in the alloy, thereby improving strength while maintaining high conductivity.

[0087] ii) Artificial aging treatment of aluminum materials after solution treatment and pre-artificial aging treatment: Pre-artificial aging treatment can form small GP zones in the aluminum materials after solution treatment, providing more nucleation sites for subsequent artificial aging treatment, thereby accelerating the formation of precipitated phases, improving the strength of the alloy, and at the same time maintaining conductivity as much as possible.

[0088] iii) Artificial aging treatment (T8, T81, T83) is applied to aluminum materials that have undergone solution treatment and cold working: Cold working increases the dislocation density in the aluminum, providing more dislocations as nucleation sites for precipitated phases, accelerating their formation, and improving the alloy's strength. Artificial aging further optimizes the distribution and size of the precipitated phases, making them finer and more uniformly distributed, thus achieving a better performance balance, improving the electrical conductivity of the aluminum alloy while maintaining good strength. This process is suitable for applications requiring high strength and good electrical conductivity.

[0089] iv) Artificial aging treatment of aluminum materials that have undergone solution treatment, pre-artificial aging treatment, and cold working: This process route combines the advantages of pre-artificial aging and cold working, while maintaining the material's machinability and dimensional accuracy. It enables faster and more uniform formation of precipitated phases, resulting in higher strength and good conductivity, making it suitable for applications with high performance requirements. This process route allows for precise control of aluminum alloy properties through meticulous control of each process parameter, meeting the needs of different application fields.

[0090] In summary, each of the four process routes has its own characteristics and applicable scenarios. By selecting the appropriate process route and parameters, the performance of aluminum alloys can be optimized for different application requirements.

[0091] It is worth noting that the four process routes mentioned above can be selectively implemented based on actual usage and performance requirements. For example, some applications may prioritize increasing conductivity at the expense of some strength, or vice versa. Therefore, in actual production, appropriate process routes and aging treatment conditions can be flexibly selected according to specific needs to achieve the best performance balance.

[0092] The aluminum alloy material prepared through the above steps achieves the predetermined range of electrical conductivity and strength. This embodiment employs a comprehensively optimized process through steps a)-h), utilizing the synergistic effects of compositional optimization design, solution treatment, pre-artificial aging treatment, cold working, and artificial aging treatment to improve the electrical conductivity and strength of the aluminum alloy. This effectively solves the contradiction between conductivity and strength in traditional aluminum alloys. The preparation process of this application has a short flow, fast production cycle, saves energy and time, and has significant economic benefits. Using the process of this application, highly conductive aluminum alloy materials can be prepared, which possess excellent electrical conductivity and good strength characteristics, meeting their application requirements in new energy vehicles, photovoltaic solar panels, battery energy storage systems, wind power generation devices, and other fields.

[0093] The aluminum alloy material prepared by the above steps has fine and uniform recrystallized grains and non-recrystallized grains extending along the deformation direction. The grains mainly exhibit a grain-to-deformation-direction relationship. <111> Orientation and perpendicular to the deformation direction <100> The orientation of the aluminum alloy is characterized by needle-like β″ precipitates within the grains and spherical β′ or β precipitates at the grain boundaries. This specific microstructure allows the alloy to simultaneously achieve high electrical conductivity and strength, expanding the application areas of high-conductivity aluminum alloys. This enables the alloy to be widely used in electrical connection components for new energy vehicles, conductive frames for photovoltaic solar panels, conductive connectors for battery energy storage systems, and conductive components for wind power generation devices.

[0094] The features and performance of the present invention will be further described in detail below with reference to embodiments. Example

[0095] This embodiment provides a highly conductive aluminum alloy, the preparation method of which is as follows:

[0096] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.4%, Mg 0.45%, Cu 0.002%, Mn 0.005%, Cr 0.005%, Zn 0.005%, Ti 0.003%, Fe 0.05%.

[0097] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0098] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform treatment at a temperature of 535℃ for 8 hours.

[0099] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 60 to obtain aluminum material.

[0100] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 530℃, and the holding time is 1 hour.

[0101] 6) Perform drawing treatment on solution-treated aluminum materials.

[0102] 7) Perform T61 aging treatment on the cold-worked aluminum material, that is, perform the treatment at a temperature of 215℃ for 6 hours.

[0103] For microstructure analysis of the high conductivity aluminum alloy obtained in this embodiment, please refer to [link to relevant documentation]. Figure 1-2 , Figure 1 Approximately spherical β′ and β phases can be observed at the grain boundaries, with the β phase having a size of approximately 80 nm and the β′ phase approximately 30 nm. Figure 2 The inner edge of the crystal can be seen <001> Al Needle-shaped β″ phases precipitated. These needle-shaped precipitates are approximately 5 nm in diameter and less than 90 nm in length. The figure also shows a small number of dislocations within the crystal, with the needle-shaped β″ phases attached to the surrounding area, indicating that the presence of dislocations promotes the precipitation of the β″ phase. This embodiment achieves a balance between high electrical conductivity and excellent strength through precise control of the alloy composition and heat treatment process.

[0104] The detection data for Example 1 are shown in Table 1. Example

[0105] This embodiment provides a highly conductive aluminum alloy, the preparation method of which is as follows:

[0106] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.4%, Mg 0.45%, Cu 0.005%, Mn 0.005%, Cr 0.005%, Zn 0.003%, Ti 0.003%, Fe 0.05%.

[0107] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0108] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform the treatment at a temperature of 520℃ for 8 hours.

[0109] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 50 to obtain aluminum material.

[0110] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 530℃, and the holding time is 1 hour.

[0111] 6) Perform pre-artificial aging treatment on the solution-treated aluminum material at a temperature of 180℃ for 3 hours.

[0112] 7) Perform drawing treatment on aluminum materials that have undergone pre-artificial aging treatment.

[0113] 8) Perform T6 aging treatment on the cold-worked aluminum material, that is, perform the treatment at a temperature of 200℃ for 10 hours.

[0114] The detection data for Example 2 are shown in Table 1. Example

[0115] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.4%, Mg 0.45%, Cu 0.002%, Mn 0.005%, Cr 0.005%, Zn 0.005%, Ti 0.003%, Fe 0.05%.

[0116] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0117] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform treatment at a temperature of 530℃ for 8 hours.

[0118] 4) The homogeneous casting is rolled and deformed by 70% to obtain aluminum material.

[0119] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 535℃, and the holding time is 1 hour.

[0120] 6) The solution-treated aluminum material is subjected to T63 aging treatment, which is carried out at a temperature of 200℃ for 10 hours.

[0121] The detection data for Example 3 are shown in Table 1. Example

[0122] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.45%, Mg 0.6%, Cu 0.005%, Mn 0.004%, Cr 0.005%, Zn 0.002%, Ti 0.003%, Fe 0.05%.

[0123] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0124] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform the treatment at a temperature of 525℃ for 8 hours.

[0125] 4) The homogeneous casting is rolled and deformed by a rolling deformation of 75% to obtain aluminum material.

[0126] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 525℃, and the holding time is 1 hour.

[0127] 6) Perform pre-artificial aging treatment on the solution-treated aluminum material at a temperature of 170℃ for 4 hours.

[0128] 7) The aluminum material that has undergone pre-artificial aging treatment is subjected to T64 aging treatment, which is carried out at a temperature of 270℃ for 7 hours.

[0129] The detection data for Example 4 are shown in Table 1. Example

[0130] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.35%, Mg 0.5%, Cu 0.002%, Mn 0.005%, Cr 0.003%, Zn 0.005%, Ti 0.003%, Fe 0.04%.

[0131] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0132] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform treatment at a temperature of 530℃ for 8 hours.

[0133] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 65 to obtain aluminum material.

[0134] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 520℃, and the holding time is 1 hour.

[0135] 6) The solution-treated aluminum material is subjected to T65 aging treatment, which is carried out at a temperature of 220℃ for 3 hours.

[0136] The detection data for Example 5 are shown in Table 1. Example

[0137] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.4%, Mg 0.55%, Cu 0.003%, Mn 0.003%, Cr 0.004%, Zn 0.004%, Ti 0.003%, Fe 0.05%.

[0138] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0139] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform the treatment at a temperature of 520℃ for 8 hours.

[0140] 4) The homogeneous casting is rolled and deformed by 70% to obtain aluminum material.

[0141] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 530℃, and the holding time is 1 hour.

[0142] 6) Perform pre-artificial aging treatment on the solution-treated aluminum material at a temperature of 165℃ for 3 hours.

[0143] 7) The aluminum material that has undergone pre-artificial aging treatment is cold rolled, with a deformation of about 1%.

[0144] 8) Perform T64 aging treatment on the cold-worked aluminum material, that is, perform the treatment at a temperature of 270℃ for 6 hours.

[0145] The detection data for Example 6 are shown in Table 1. Example

[0146] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.45%, Mg 0.6%, Cu 0.003%, Mn 0.005%, Cr 0.003%, Zn 0.005%, Ti 0.003%, Fe 0.04%.

[0147] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0148] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform treatment at a temperature of 530℃ for 8 hours.

[0149] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 45 to obtain aluminum material.

[0150] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 525℃, and the holding time is 1 hour.

[0151] 6) The solution-treated aluminum material is then drawn.

[0152] 7) Perform T63 aging treatment on the cold-worked aluminum material, that is, perform the treatment at a temperature of 210℃ for 10 hours.

[0153] The detection data for Example 7 are shown in Table 1. Example

[0154] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.35%, Mg 0.5%, Cu 0.002%, Mn 0.002%, Cr 0.003%, Zn 0.001%, Ti 0.002%, Fe 0.03%.

[0155] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0156] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform the treatment at a temperature of 520℃ for 8 hours.

[0157] 4) The homogeneous casting is rolled and deformed by 80% to obtain aluminum material.

[0158] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 530℃, and the holding time is 1 hour.

[0159] 6) Perform pre-artificial aging treatment on the solution-treated aluminum material at a temperature of 170℃ for 4 hours.

[0160] 7) The aluminum material that has undergone pre-artificial aging treatment is subjected to T6 aging treatment, that is, treatment is carried out at a temperature of 200℃ for 10 hours.

[0161] The detection data for Example 8 are shown in Table 1. Example

[0162] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.4%, Mg 0.45%, Cu 0.002%, Mn 0.003%, Cr 0.005%, Zn 0.002%, Ti 0.003%, Fe 0.05%.

[0163] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0164] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform the treatment at a temperature of 525℃ for 8 hours.

[0165] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 30 to obtain aluminum material.

[0166] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 520℃, and the holding time is 1 hour.

[0167] 6) Perform drawing treatment on solution-treated aluminum materials.

[0168] 7) Perform T61 aging treatment on the cold-worked aluminum material, that is, perform the treatment at a temperature of 215℃ for 6 hours.

[0169] The detection data for Example 9 are shown in Table 1.

[0170] Example 10:

[0171] 1) Provide alloy raw materials, wherein the concentration of alloying elements is: Si 0.45%, Mg 0.50%, Cu 0.01%, Mn 0.02%, Cr 0.01%, Zn 0.005%, Ti 0.003%, Fe 0.07%, B 0.0012%.

[0172] 2) The alloy raw materials are smelted and cast to form castings with a hydrogen content of less than 0.15 ml / 100 g Al.

[0173] 3) The castings are subjected to homogenization heat treatment to obtain homogeneous castings. The homogenization heat treatment regime is to perform treatment at a temperature of 530℃ for 8 hours.

[0174] 4) The homogeneous casting is extruded and deformed at an extrusion ratio of 40 to obtain aluminum material.

[0175] 5) The aluminum material is subjected to solution treatment to obtain the solution-treated aluminum material. The solution temperature is 525℃, and the holding time is 1 hour.

[0176] 6) Perform pre-artificial aging treatment on the solution-treated aluminum material at a temperature of 170℃ for 3 hours.

[0177] 7) Perform T64 aging treatment on aluminum materials that have undergone pre-artificial aging treatment, that is, perform the treatment at a temperature of 275℃ for 7 hours.

[0178] The detection data for Example 10 are shown in Table 1.

[0179] Table 1: Detection data from the example.

[0180] Example Electrical conductivity (%IACS) Tensile strength (MPa) Elongation (%) Example 1 59.2 245.2 17.8 Example 2 57.8 295.3 13.6 Example 3 59.5 260.6 15.5 Example 4 59.0 265.5 16.2 Example 5 59.3 255.3 16.5 Example 6 60.0 250.7 17.5 Example 7 59.3 268.3 15.8 Example 8 58.3 282.1 14.1 Example 9 58.5 290.5 12.4 Example 10 58.8 264.6 15.8

[0181] Comparative Example 1:

[0182] 1) Alloy material preparation: Alloy composition: Si 0.5%, Mg 0.7%, Cu 0.02%, Mn 0.03%, Cr 0.05%, Zn 0.005%, Ti 0.003%, Fe 0.1%

[0183] 2) Smelting and casting: The alloy raw materials are smelted and then directly cast into ingots. The hydrogen content of the ingots is not specially controlled.

[0184] 3) Homogenization heat treatment: Homogenization heat treatment is carried out at 530℃ for 6 hours.

[0185] 4) Deformation process: The traditional extrusion process is adopted, and the extrusion ratio is set to 40.

[0186] 5) Solution heat treatment: Solution treatment is carried out at 535℃ and held for 2 hours.

[0187] 6) T6 aging treatment: Heat the solution-treated aluminum material to 190℃, hold for 6 hours, and then air cool to room temperature.

[0188] 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 embodiments of this invention. Its tensile strength was 215 MPa, and its elongation was 12%, indicating poor overall performance compared to the embodiments of this invention.

[0189] Comparative Example 2:

[0190] The preparation method and performance of conductive aluminum alloys are referenced in standard GB / T 3954-2022 "Electrical Round Aluminum Rods".

[0191] Brand state Tensile strength / MPa Elongation / % Conductivity / %IACS 6101 T4 160 10 34.50

[0192] Comparative Example 3:

[0193] The preparation methods and properties of conductive aluminum alloys are referenced in standard GB / T 27676-2011 "Aluminum and Aluminum Alloy Tubular Conductors".

[0194] Brand state Tensile strength / MPa Elongation / % Conductivity / %IACS 6101 T5A, T6 200 10.0 ≥55.0 6101 T10 170 - ≥55.0 6063 T5A, T6 205 8.0 ≥51.0 6063 T10 180 - ≥51.0

[0195] Comparative Example 4:

[0196] The preparation method and performance of conductive aluminum alloys are referenced in standard GB / T 6892-2023 "General Industrial Aluminum and Aluminum Alloy Extruded Profiles".

[0197] Brand state Tensile strength / MPa Elongation / % Conductivity / %IACS 6101B T6 215 8.0 ≥48.27 6063 T4 - - ≥43.1 6063 T5, T6 - - ≥48.27

[0198] Comparative Example 5:

[0199] The preparation method and properties of conductive aluminum alloys refer to the European standard DIN EN 755-2 Aluminium and aluminum alloys - Extruded rod / bar, tube and profiles - Part 2: Mechanical properties.

[0200] Brand state Tensile strength / MPa Elongation / % Conductivity / %IACS 6101B T6 215 8.0 51.7 6101B T7 170 12.0 55.0

[0201] Comparative Example 6:

[0202] The preparation methods and properties of conductive aluminum alloys are referenced in the American Aluminum Alloy Handbook ISSN 2377-6838 TempersFor Aluminum and Aluminum Alloy Products.

[0203] Brand state Tensile strength / MPa Elongation / % Conductivity / %IACS 6101 T1 110 - 50.0 6101 T8 303 3.5 53.0 6101 T83 248 4.0 57.5

[0204] By comparing the above embodiments with the comparative examples, it can be found that the high conductivity aluminum alloy material provided in this application exhibits excellent electrical conductivity and mechanical properties under different preparation conditions, and its comprehensive electrical conductivity and strength performance are higher than those of the comparative examples.

[0205] This result demonstrates that the alloy composition, heat treatment process, and process route of this application have a significant impact on the microstructure and properties of the aluminum alloy. Through appropriate design and optimization, highly conductive aluminum alloy materials that meet specific application requirements can be obtained. The preparation method of this application has advantages such as simple process flow, high production efficiency, energy saving, and environmental protection, making the resulting aluminum alloy material have broad application prospects, especially suitable for electrical connection components in new energy vehicles, conductive frames for photovoltaic solar panels, conductive connectors for battery energy storage systems, and conductive components for wind power generation devices.

[0206] It should be noted that, where there is no conflict, the features in the embodiments of this application can 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 can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A high-conductivity aluminum alloy material, characterized in that, The aluminum alloy belongs to the Al-Mg-Si system. The alloying elements in the aluminum alloy include: Si 0.3-0.5%, Mg 0.35-0.65%, Cu <0.01%, Mn <0.01%, Cr <0.01%, Zn <0.01%, Ti <0.005%, Fe <0.1%, B 0~x%, and other individual elements <0.005%. When the total amount of Mn, Cr, and Ti is less than 0.015%, B is not added. When the total amount exceeds 0.015%, the amount of B added (x%) is calculated based on 1.25 to 1.5 times the stoichiometric coefficient of B required to form borides with Mn, Cr, Ti, and B. The microstructure of the aluminum alloy has the following characteristics: its microstructure contains fine and uniform recrystallized grains and non-recrystallized grains extending along the deformation direction, wherein the proportion of recrystallized grains is 30% to 50%, and the size of the recrystallized grains is less than 5 μm; the grains mainly exhibit an orientation along the deformation direction. <111> Orientation and perpendicular to the deformation direction <100> Orientation; within the grain, along <001> Al and <111> Al Needle-shaped β″ precipitates precipitate in three equivalent directions, with a diameter less than 10 nm and a length less than 100 nm; <001> Al Spherical β′ and / or β precipitates are formed at grain boundaries; the intragranular dislocation density is less than 2.5 × 10⁻⁶. 14 m -2 The total resistivity of the aluminum alloy ρ total It is less than 29.5 nΩm, and its conductivity is in the range of 58% to 60% IACS.

2. The high conductivity aluminum alloy material according to claim 1, characterized in that... The total resistivity ρ total From the parent metal ρ base dislocation ρ disl Grain boundary ρ GB and alloy solute atoms ρ ss and precipitate phase ρ precip The sum of contributions constitutes the equation, satisfying the following relationship: ρ total = ρ base + L disl Δρ disl + S GB Δρ GB +∑ ρ alloy ( c i , α i )+∑ ρ precip ( f parj , s j , d j ) in: ρ base This is the resistivity of pure aluminum, with a value of 26.55 nΩm; Δρ disl It is the increase in resistivity caused by dislocations resulting from pressure deformation, per unit dislocation. Δρ disl The value is 2.7 × 10 −25 Ωm 3 , ρ disl solid solution temperature T sol It has a lower value in the range of 520-535℃; ρ GB Resistivity representing the increase in grain size, per unit grain boundary Δρ GB The value is 2.6 × 10 −16 Ωm 2 ; ∑ ρ alloy ( c i , α i The increase in resistivity represents the increase of the alloying element, taking into account the element's properties. c i The concentration and corresponding resistivity coefficient α i Concentration per unit (at.%) ρ ss It is 0.4-0.9×10 -8 Ωm, where c i The concentration range is: Si 0.3-0.5%, Mg 0.35-0.65%, Cu <0.01%, Mn <0.01%, Cr <0.01%, Zn <0.01%, Ti <0.005%, Fe <0.1%, B 0~ x %, with other individual elements < 0.005%; ∑ ρ precip ( f parj , s j , d j The ) represents the increase in resistivity due to the precipitated phase, taking into account the precipitated phase. j volume fraction f parj ,size s j and density d j precipitate phase j The electrical conductivity and strength of the alloy can be optimized by adjusting any one of the artificial aging treatment states: T6, T61, T63, T64, or T65.

3. The high conductivity aluminum alloy material according to claim 1, characterized in that... One of the following five artificial aging processes is used to optimize the electrical conductivity and strength of the alloy: T6 aging treatment: The treatment is carried out in a temperature range of 190℃ to 220℃ for a duration of 8 to 12 hours; T61 aging treatment: The treatment is carried out in the temperature range of 215℃ to 245℃ for a duration of 4 to 8 hours; T63 aging treatment: The treatment is carried out in a temperature range of 200℃ to 230℃ for a duration of 8 to 12 hours; T64 aging treatment: The treatment is carried out in a temperature range of 260℃ to 290℃ for a duration of 6 to 9 hours; T65 aging treatment: The treatment is carried out in the temperature range of 205℃ to 235℃ for a duration of 2 to 5 hours.

4. A method for preparing a high-conductivity aluminum alloy material as described in any one of claims 1 to 3, characterized in that... Perform the following steps in sequence: a) Provide alloy raw materials according to the proportions of alloying elements; b) The alloy raw materials are melted and cast to form castings; c) Perform homogenization heat treatment on the castings to obtain homogeneous castings; d) The homogeneous casting is pressure processed to obtain aluminum material; e) Perform a solution treatment on the aluminum material to obtain a solution-treated aluminum material; f) Optionally, the solution-treated aluminum material may undergo pre-artificial aging treatment; g) Optionally, the solution-treated aluminum material may be subjected to cold working. h) Optionally, the solution-treated aluminum material is subjected to pre-artificial aging treatment followed by cold working. i) Perform artificial aging treatment on aluminum materials that have undergone solution treatment, or aluminum materials that have undergone solution treatment followed by pre-artificial aging treatment, or aluminum materials that have undergone solution treatment followed by cold working treatment, or aluminum materials that have undergone solution treatment, pre-artificial aging treatment and cold working treatment. The aluminum alloy material prepared by the above steps has electrical conductivity and strength within the predetermined range.

5. The method for preparing a high-conductivity aluminum alloy material according to claim 4, characterized in that... The hydrogen content of the alloy after smelting should be less than 0.15 ml / 100 g Al.

6. The method for preparing a high-conductivity aluminum alloy material according to claim 4, characterized in that... The homogenization heat treatment process involves treatment at a temperature range of 500°C to 550°C for a duration of 6 to 10 hours.

7. The method for preparing a high-conductivity aluminum alloy material according to claim 4, characterized in that... Pressure processing can be either extrusion or rolling. If extrusion deformation is used, the extrusion ratio is 20 to 80. If rolling deformation is used, the rolling deformation amount is 60% to 85%.

8. The method for preparing a high-conductivity aluminum alloy material according to claim 4, characterized in that... The pre-artificial aging treatment is carried out at a temperature range of 160°C to 180°C for a duration of 1 to 5 hours.

9. The application of the high conductivity aluminum alloy material according to claim 1, characterized in that, The aforementioned high-conductivity aluminum alloy material is used in 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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