Ultrahigh-strength high-conductivity thin and long grain aluminum alloy material and preparation method thereof

Abstract

The invention belongs to the field of metallurgical wire processing, and relates to an aluminum alloy material, in particular to an ultrahigh-strength high-conductivity slender grain aluminum alloy material and a preparation method thereof. The aluminum alloy material is prepared from the following elements in percentage by mass: 0.56 percent to 0.75 percent of Si, 0.2 percent to 0.5 percent of Fe, 0.005 percent to 0.15 percent of Cu, 0.45 percent to 0.85 percent of Mg, 0.1 percent to 0.25 percent of RE, 0.005 percent to 0.03 percent of B, 0.001 percent to 0.02 percent of Ti and the balance of aluminum, the preparation method comprises the processes of smelting, alloying treatment, refining, continuous casting, continuous rolling, quenching, drawing, tempering recrystallization and aging treatment in sequence. By setting the aluminum alloy material formula and improving the preparation method, the distribution of grain boundaries is optimized, and the strength and the conductivity of the aluminum alloy conductor are synchronously improved.

Description

Technical Field

[0001] The present invention belongs to the field of metallurgical wire processing and relates to aluminum alloy materials, and in particular to an ultra-high strength, high conductivity, elongated grain aluminum alloy material and a preparation method thereof. Background Art

[0002] Aluminum alloy, one of the most widely used nonferrous metals in industry, has found widespread application in aviation, aerospace, automotive, machinery manufacturing, shipbuilding, and the chemical industry. High-strength aluminum alloy rods, a key functional material, are primarily used in overhead conductors and insulated cables. Their core function as a conductor is to efficiently conduct current. Furthermore, their high strength and excellent corrosion resistance make them highly sought after in the field of wire transmission.

[0003] However, after forming, traditional aluminum or aluminum alloy rods face bottlenecks in improving key performance indicators (such as tensile strength and electrical conductivity) due to the metal's internal crystallization characteristics and imperfect material structure. Currently, industry standards clearly define the performance of high-strength aluminum alloy rods: after T6 treatment, the tensile strength of rods with a diameter of 3.5mm or larger must be no less than 315MPa, and that of rods with a diameter of less than 3.5mm must be no less than 325MPa; meanwhile, the resistivity must be ≤32.84nΩ·m (corresponding to 52.5% IACS). However, the actual performance levels achieved within the industry remain largely limited to these standards, with no significant breakthroughs yet. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention provides an ultra-high-strength, high-conductivity, elongated-grain aluminum alloy material and its preparation method. This invention improves the grain boundary arrangement of the material by defining a specific aluminum alloy formulation and adjusting the distribution of grain boundaries. By improving the distribution of crystals and achieving a directional texture, the material achieves simultaneous increases in tensile strength and conductivity. Through directional grain boundary regulation and controlled axial grain solid solution precipitation, the strength and conductivity of the aluminum alloy conductor are simultaneously enhanced.

[0005] In order to achieve the above object, the technical solution of the present invention is: In a first aspect, an ultra-high strength and high conductivity elongated grain aluminum alloy material is composed of the following elements, calculated by mass percentage: Si: 0.56-0.75%, Fe: 0.2-0.5%, Cu: 0.005-0.15%, Mg: 0.45-0.85%, RE: 0.1-0.25%, B: 0.005-0.03%, Ti: 0.001-0.02%, and the remainder is aluminum; Among them, RE is a rare earth element.

[0006] In a second aspect, a method for preparing the above-mentioned ultra-high strength, high conductivity, elongated grain aluminum alloy material comprises the following steps: smelting, alloying, refining, continuous casting, continuous rolling, quenching, drawing, tempering and recrystallization, and aging treatment; The continuous casting process involves continuous casting in an inert atmosphere below atmospheric pressure at a temperature of 690-740°C. During the continuous casting process, the molten aluminum sequentially enters several temperature zones, and the average temperature of each temperature zone gradually decreases as the aluminum flows. The temperature within each temperature zone also gradually decreases as the aluminum flows. Furthermore, between two adjacent temperature zones, the outlet temperature of the upstream temperature zone is lower than the inlet temperature of the downstream temperature zone. The process of tempering and recrystallization is as follows: the drawn aluminum alloy single wire is placed at a temperature of 110-120°C for constant temperature treatment, and then placed at room temperature for constant temperature treatment.

[0007] In a third aspect, a use of the above-mentioned ultra-high strength, high conductivity, slender grain aluminum alloy material in overhead conductors or overhead insulated cables.

[0008] The beneficial effects of the present invention are: 1. The aluminum alloy material provided by this invention, with its synergistic effect of 0.2-0.5% iron and 0.1-0.25% rare earth, can improve the ductility of the alloy rod, optimize the composition of the liquid aluminum, refine the grain size, remove slag, and enhance corrosion resistance. It also removes gases and harmful impurities from the aluminum alloy, reducing crack sources, thereby increasing its strength and improving its processing properties. It also improves its fluidity, plasticity, and workability, resists repeated bending, and increases its hardness, strength, and toughness.

[0009] 2. In the aluminum alloy material provided by the present invention, the boron content is controlled at 0.005-0.03%. During the casting process of the aluminum alloy material system of the present invention, it can improve the fluidity of aluminum, reduce the adverse effects of other elements in the aluminum, form nuclei, and thus form non-spontaneous nucleation, which has the effect of grain refinement. In addition, the 0.005-0.03% boron content, combined with other elements in the aluminum alloy material system of the present invention, can improve the material's electrical conductivity by up to 6-10%.

[0010] 3. Adding 0.001-0.02% of titanium to the aluminum alloy material system provided by the present invention can play a significant role in the metal grain structure, thereby facilitating the directional control of the metal grain structure during the casting process.

[0011] 4. In the aluminum alloy preparation method provided by the present invention, during the continuous casting process, low-pressure casting is performed and the casting temperature is regulated. This allows for directional crystallization under the combined effects of pressure and temperature. Subsequently, a drawing process is performed to achieve ultra-slenderization of the metal grain structure. Finally, tempering, recrystallization, and aging treatments are performed to strengthen the axial dislocation texture, thereby significantly improving the strength of the aluminum alloy. Furthermore, the ultra-slenderization of the metal grain structure through drawing can reduce obstacles to electron transport in the aluminum alloy, thereby reducing resistivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0013] Figure 1 This is a process flow chart of a method for preparing an ultra-high strength, high conductivity, elongated grain aluminum alloy material according to Example 1 of the present invention; Figure 2 This is a diagram showing the settings of various temperature zones for continuous casting in Example 1 of the present invention; Figure 3 Schematic diagram of the structure of the grain orientation control device in Example 1 of the present invention, wherein 1 is a low thermal conductivity ceramic mold shell of the furnace lining insulation material, 2 is the atmosphere furnace, 3 is the aluminum liquid (melt), 4 is the orientation baffle, 5 is the orientation crystallization zone, 6 is the heat conduction layer, 7 is the ingot, and 8 is nitrogen; Figure 4 This is a schematic diagram of the quenching zones in Example 1 of the present invention. DETAILED DESCRIPTION

[0014] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention belongs.

[0015] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0016] In view of the fact that the tensile strength and electrical conductivity of existing aluminum alloy rods need to be further improved, the present invention proposes an ultra-high strength, high electrical conductivity, elongated grain aluminum alloy material and a preparation method thereof.

[0017] A typical embodiment of the present invention provides an ultra-high strength and high conductivity slender grain aluminum alloy material, which is composed of the following elements, calculated by mass percentage: Si: 0.56-0.75%, Fe: 0.2-0.5%, Cu: 0.005-0.15%, Mg: 0.45-0.85%, RE: 0.1-0.25%, B: 0.005-0.03%, Ti: 0.001-0.02%, and the balance is aluminum; Among them, RE is a rare earth element.

[0018] The aluminum alloy material of the present invention contains other inevitable elements, and the present invention does not limit other elements. The total mass percentage of other elements is less than 0.15%.

[0019] In some embodiments, RE is La and Ce. Specifically, the mass ratio of La to Ce is 1:2.0-2.5.

[0020] In some embodiments, Si: 0.56-0.63%, Fe: 0.20-0.30%, Cu: 0.01-0.15%, Mg: 0.60-0.75%, RE: 0.10-0.15%, B: 0.010-0.020%, Ti: 0.005-0.015%, and the balance is aluminum.

[0021] Another embodiment of the present invention provides a method for preparing the above-mentioned ultra-high strength, high conductivity, elongated grain aluminum alloy material, comprising the steps of smelting, alloying, refining, continuous casting, continuous rolling, quenching, drawing, tempering and recrystallization, and aging treatment in sequence; The continuous casting process involves continuous casting in an inert atmosphere below atmospheric pressure at a temperature of 690-740°C. During the continuous casting process, the molten aluminum sequentially enters several temperature zones, and the average temperature of each temperature zone gradually decreases as the aluminum flows. The temperature within each temperature zone also gradually decreases as the aluminum flows. Furthermore, between two adjacent temperature zones, the outlet temperature of the upstream temperature zone is lower than the inlet temperature of the downstream temperature zone. The process of tempering and recrystallization is as follows: the drawn aluminum alloy single wire is placed at a temperature of 110-120°C for constant temperature treatment, and then placed at room temperature for constant temperature treatment.

[0022] In the present invention, to achieve continuous casting under subatmospheric pressure, the continuous casting apparatus is sealed. Sealing the continuous casting apparatus facilitates pressure control. Subatmospheric pressure is 0.2-0.5 standard atmospheres (ATM), where 1 ATM is 101 kPa. The inert atmosphere of the present invention can be an atmosphere formed by an inert gas such as nitrogen, helium, argon, or xenon.

[0023] In some embodiments, the temperature zones that the molten aluminum enters in sequence are the crystallization temperature zone, the crystal stabilization temperature zone, the weak cooling temperature zone, and the strong cooling temperature zone. The temperature of the crystallization temperature zone is 708-740°C, the temperature of the crystal stabilization temperature zone is 705-738°C, the temperature of the weak cooling temperature zone is 702-716°C, and the temperature of the strong cooling temperature zone is 695-712°C. The casting distances of the molten aluminum in the crystallization temperature zone, the crystal stabilization temperature zone, the weak cooling temperature zone, and the strong cooling temperature zone increase in sequence.

[0024] Within each temperature zone, the molten aluminum is divided into three sections along the casting path: upstream, midstream, and downstream. The average temperatures of the upstream, midstream, and downstream sections decrease in that order. Specifically, the temperature in the upstream, midstream, and downstream sections of the crystallization temperature zone is 732-740°C, 718-725°C, and 708-715°C, respectively.

[0025] Specifically, the temperature of the upstream section of the crystallization temperature zone is 722-738°C, the temperature of the midstream section of the crystallization temperature zone is 714-719°C, and the temperature of the downstream section of the crystallization temperature zone is 705-709°C.

[0026] Specifically, the temperature of the upstream section of the weak cooling section temperature zone is 715-716°C, the temperature of the midstream section of the weak cooling section temperature zone is 707-714°C, and the temperature of the downstream section of the weak cooling section temperature zone is 702-704°C.

[0027] Specifically, the temperature of the upstream section of the strong cooling section temperature zone is 708-712°C, the temperature of the midstream section of the strong cooling section temperature zone is 702-706°C, and the temperature of the downstream section of the strong cooling section temperature zone is 695-700°C.

[0028] In some embodiments, the continuous casting method is horizontal casting at a casting speed of 4 to 6 t / h.

[0029] In some embodiments, during the tempering recrystallization, the constant temperature treatment time at a temperature of 110-120° C. is 4-6 hours.

[0030] In some embodiments, during tempering and recrystallization, the constant temperature treatment time at room temperature is 16-24 hours.

[0031] In some embodiments, the smelting process involves heating and melting aluminum metal raw material under an inert atmosphere. Specifically, the smelting temperature is 750-780°C. Specifically, the aluminum metal raw material is industrial-grade Al99.70 pure aluminum. This raw material offers advantages such as abundant supply, low cost, and easy procurement. Alternatively, the aluminum metal raw material may utilize refined aluminum or high-purity aluminum as the base alloy. This aluminum matrix is ​​of higher quality than standard aluminum-based materials, resulting in products with superior electrical and mechanical properties.

[0032] In some embodiments, the alloying process involves adding a master alloy to the molten aluminum according to a specific ratio. Specifically, the alloying process utilizes manual stirring, electromagnetic stirring, or permanent magnetic stirring to ensure uniform mixing of the molten aluminum. The alloying process is typically performed at a temperature of 730-750°C.

[0033] In some embodiments, the refining process includes furnace refining and external refining. Specifically, the furnace refining temperature is 740-760°C. Specifically, the furnace refining process involves adding a refining agent to the molten aluminum (or melt) under an inert atmosphere. More specifically, the refining agent is sprayed into the molten aluminum using nitrogen or an inert gas as a carrier. Specifically, after furnace refining, slag is skimmed to remove any slag floating on the surface of the molten aluminum. Specifically, after skimming, the composition of the molten aluminum is adjusted to ensure the following: Al ≥ 97.10 wt%, Si: 0.56-0.75 wt%, Fe: 0.2-0.5 wt%, Cu: 0.005-0.15 wt%, Mg: 0.45-0.85 wt%, B: 0.005-0.03 wt%, Ti: 0.001-0.02 wt%, and RE: 0.1-0.25 wt%. Specifically, the aluminum is refined in the furnace until the aluminum liquid temperature reaches 740-760°C, and then refined outside the furnace. Specifically, the refining outside the furnace is sequentially performed by online degassing and double-stage filtration.

[0034] In some embodiments, the continuous casting ingot is heated to 520-540° C. and then continuously rolled. Rolling at 520-540° C. can better organically combine the various components, which is beneficial to improving the performance of the aluminum alloy rod.

[0035] In some embodiments, during continuous rolling, an emulsion is used for lubrication and cooling. Specifically, the pressure and flow rate of the emulsion are adjusted to ensure that the final rolling temperature of the aluminum alloy rod is ≤300°C.

[0036] In some embodiments, the aluminum alloy rod is quenched using water or emulsion after continuous rolling.

[0037] In some embodiments, the surface temperature of the aluminum alloy rod after continuous rolling is controlled by quenching to be ≤70° C. This condition is more conducive to ensuring the strength of the aluminum alloy rod.

[0038] In some embodiments, quenching is performed using a zoned process. Specifically, the aluminum alloy after continuous rolling is quenched in sequence through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, and quenching zone 5. More specifically, the cooling temperature of quenching zone 1 is 28-32°C, and the pressure of cooling water is 0.19-0.21 MPa. More specifically, the cooling temperature of quenching zone 2 is 28-32°C, and the pressure of cooling water is 0.29-0.31 MPa. More specifically, the cooling temperature of quenching zone 3 is 23-27°C, and the pressure of cooling water is 0.29-0.31 MPa. More specifically, the cooling temperature of quenching zone 4 is 18-22°C, and the pressure of cooling water is 0.29-0.31 MPa. More specifically, the cooling temperature of quenching zone 5 is 18-22°C, and the pressure of cooling water is 0.34-0.36 MPa.

[0039] In some embodiments, the steel sheet is naturally cooled after quenching and then drawn, and the natural cooling time is not less than 24 hours.

[0040] In some embodiments, the aging treatment is a two-stage aging treatment, and the temperature of the first aging treatment is different from the temperature of the second aging treatment. The axial dislocation texture strengthening effect of the two-stage aging treatment is better. Specifically, the temperature of the first aging treatment is 152-158°C. Specifically, the heating time of the first aging treatment is 1.8-2.2h, the holding time is 5.5-6.5h, and the power-off holding time is 0.9-1.1h. Specifically, the temperature of the second aging treatment is 172-178°C. Specifically, the heating time of the second aging treatment is 0.9-1.1h, and the holding time is 3.6-4.4h.

[0041] Specifically, the steps are as follows: 1) Raw material selection and smelting: Inspect the raw materials, select aluminum ingots of corresponding grades for reasonable matching, put them into the aluminum melting furnace for smelting, control the aluminum liquid temperature in the furnace ≤ 760℃, and use nitrogen (N2 ≥ 99.99% or more) as a gas protection in the furnace atmosphere; 2) Analysis of aluminum liquid composition: Transfer the smelted aluminum liquid (or electrolytic aluminum liquid) to a holding furnace, stir it evenly, and then take a sample for rapid analysis using a direct reading spectrometer to detect the content of Al, Si, Fe, Cu, Mg, B, Ti, La, and Ce in the solution; 3) Alloying treatment: Based on the spectral test results of step 2), the addition amounts of magnesium ingot, aluminum silicon, aluminum iron, aluminum copper, aluminum rare earth, aluminum boron, and aluminum titanium master alloy are calculated. When the temperature of the aluminum liquid in the holding furnace is controlled at 730-750°C, the corresponding master alloy is added, and manual and electromagnetic stirring are performed for 25-35 minutes to make the aluminum liquid composition fully uniform. The main components of the aluminum liquid are Al ≥ 97.10wt%, Si: 0.56-0.75wt%, Fe: 0.2-0.5wt%, Cu: 0.005-0.15wt%, Mg: 0.45-0.85wt%, B: 0.005-0.03wt%, Ti: 0.001-0.02wt%, and rare earth (RE): 0.1-0.25wt%. 4) Furnace refining: After completing step 3), when the aluminum liquid temperature reaches 740-760°C, use 99.999% high-purity nitrogen as a carrier to pass a high-efficiency powder refining agent into the melt in the holding furnace for refining to achieve degassing and impurity removal of the aluminum liquid. During refining, the refining agent blowing speed and nitrogen pressure are controlled to keep the refining time within 20-30 minutes and the nitrogen pressure within 10-15KPa. 5) Slag removal: After step 4) is completed, let the aluminum liquid stand for 5-10 minutes, open the slag removal door of the holding furnace to remove the slag, and clean the aluminum slag floating on the surface of the aluminum liquid; 6) Composition adjustment: The aluminum liquid after steps 4) and 5) is allowed to stand in a holding furnace for 30-40 minutes, and then sampled and analyzed. If the element content deviates, adjustments are made to confirm that the aluminum liquid composition is: Al ≥ 97.10wt%, Si: 0.56-0.75wt%, Fe: 0.2-0.5wt%, Cu: 0.005-0.15wt%, Mg: 0.45-0.85wt%, B: 0.005-0.03wt%, Ti: 0.001-0.02wt%, Rare Earth (RE): 0.1-0.25wt%; 7) Refining and slag removal outside the furnace: After step 6) is completed, when the aluminum liquid temperature reaches 730-750℃, it can be taken out of the furnace. The aluminum liquid comes out of the holding furnace and passes through the launder into the online degassing device and the two-stage filtration device for refining outside the furnace. Degassing and slag removal are carried out again. Refining agent (can be added through a wire feeder) is added to the aluminum melt in the aluminum alloy casting launder. The refining agent is Al-Ti-B wire or Al-Ti-C wire. The speed of adding the refining agent is 60-120cm / min. 8) Continuous casting: The clean aluminum liquid refined again in step 7) is continuously cast, and the ladle temperature is controlled at 690-700℃. The casting is carried out in an inert atmosphere of 0.2-0.5 standard atmospheric pressure using a horizontal casting method. The temperature zones that the aluminum liquid enters in sequence are the crystallization temperature zone, the fixed crystal temperature zone, the weak cooling temperature zone, and the strong cooling temperature zone. The temperature of the upstream section of the crystallization temperature zone is 732-740℃, the temperature of the midstream section of the crystallization temperature zone is 718-725℃, and the temperature of the downstream section of the crystallization temperature zone is 708-715℃; the fixed crystal temperature zone is 732-740℃. The temperature of the upstream section of the zone is 722-738°C, the temperature of the middle section of the fixed crystal temperature zone is 714-719°C, and the temperature of the downstream section of the fixed crystal temperature zone is 705-709°C; the temperature of the upstream section of the weak cooling section temperature zone is 715-716°C, the temperature of the middle section of the weak cooling section temperature zone is 707-714°C, and the temperature of the downstream section of the weak cooling section temperature zone is 702-704°C; the temperature of the upstream section of the strong cooling section temperature zone is 708-712°C, the temperature of the middle section of the strong cooling section temperature zone is 702-706°C, and the temperature of the downstream section of the strong cooling section temperature zone is 695-700°C; At the same time, according to the diameter range of the drawn monofilament, the speed of the crystallization wheel and the cooling water pressure are controlled to make the temperature of the billet from the crystallization wheel to the approach bridge 490-510℃; 9) Continuous Rolling: Straighten and heat the ingot produced in step 8) and maintain the ingot temperature at 520-540°C before rolling. During the rolling process, use an emulsion to lubricate and cool the rolls and aluminum rod. Adjust the emulsion pressure and flow rate to keep the aluminum alloy rod's final rolling temperature ≤300°C. 10) Aluminum rod quenching: Use water or dilute emulsion to quench the high-strength aluminum alloy rods coming out of the rolling mill - rapid cooling treatment, control the surface temperature of the aluminum rod to ≤70℃ to ensure the strength of the aluminum rod; quenching should be carried out in zones, that is, quenching in order through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, and quenching zone 5; the cooling temperature of quenching zone 1 is 28-32℃, and the pressure of cooling water is 0.19-0.21MPa; more specifically, the cooling of quenching zone 2 is 28-32℃, and the pressure of cooling water is 0.19-0.21MPa; more specifically, the cooling of quenching zone 2 is 28-32℃, and the pressure of cooling water is 0.19-0.21MPa. The temperature is 28-32°C, and the pressure of the cooling water is 0.29-0.31 MPa; more specifically, the cooling temperature of the quenching zone 3 is 23-27°C, and the pressure of the cooling water is 0.29-0.31 MPa; more specifically, the cooling temperature of the quenching zone 4 is 18-22°C, and the pressure of the cooling water is 0.29-0.31 MPa; more specifically, the cooling temperature of the quenching zone 5 is 18-22°C, and the pressure of the cooling water is 0.34-0.36 MPa; 11) Cleaning of aluminum rod: Before the aluminum rod enters the take-up frame (or winding reel), use compressed air to blow away the water on the surface of the aluminum rod to keep it clean and dry; 12) Natural cooling: The aluminum alloy rod obtained in step 11) is placed on the site for natural cooling. The cooling time shall not be less than 24 hours.

[0042] 13) Drawing and directional graining: The drawing process should adopt pre-drawing followed by formal drawing, and the wire should be drawn to the specified wire diameter (the wire diameter includes but is not limited to 2.4mm, 3.85mm, and also includes wire diameters of other specifications).

[0043] 14) Tempering and recrystallization: After the drawn aluminum alloy single wire is placed at 110-120℃ for 4-6 hours, it can be placed at room temperature for 16-24 hours before the next processing step.

[0044] 15) Double-stage aging treatment: The material treated in 14) is placed in a heat treatment device for aging treatment: First aging treatment process: 152-158℃ / (1.8-2.2)+(5.5-6.5)+(0.9-1.1)h (heating + holding + power off holding); Second aging treatment process: 172-178℃ / (0.9-1.1)+(3.6-4.4)h (heating + insulation).

[0045] A third embodiment of the present invention provides a use of the above-mentioned ultra-high strength, high conductivity, elongated grain aluminum alloy material in overhead conductors or overhead insulated cables.

[0046] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0047] Example 1 A method for preparing an ultra-high strength and high conductivity slender grain aluminum alloy material, such as Figure 1 As shown, the steps are as follows: 1) Raw material selection and smelting: Inspect the raw materials, select Al99.70 aluminum ingots, put them into the aluminum melting furnace for smelting, control the aluminum liquid temperature in the furnace at 760℃, and use nitrogen (N2 ≥ 99.99% or more) as the gas protection in the furnace.

[0048] 2) Analysis of aluminum liquid composition: The smelted aluminum liquid is transferred to a holding furnace, stirred evenly, and then sampled for rapid analysis using a direct reading spectrometer to detect the contents of Al, Si, Fe, Cu, Mg, B, Ti, La, and Ce in the solution.

[0049] 3) Alloying treatment: Based on the spectral test results in step 2) and the composition in Table 1, calculate the amount of magnesium ingot, aluminum silicon, aluminum iron, aluminum copper, aluminum rare earth, aluminum boron, and aluminum titanium master alloy to be added. When the temperature of the aluminum liquid in the holding furnace is controlled at 750°C, add the corresponding master alloy and stir manually and electromagnetically for 30 minutes to make the aluminum liquid composition fully uniform.

[0050] 4) Furnace refining: After completing step 3), when the aluminum liquid temperature reaches 750°C, use 99.999% high-purity nitrogen as a carrier to pass a high-efficiency powder spray refining agent into the melt in the holding furnace for refining to achieve degassing and impurity removal of the aluminum liquid. During refining, the refining agent blowing speed and nitrogen pressure are controlled to keep the refining time within 30 minutes and the nitrogen pressure within 15KPa.

[0051] 5) Slag removal: After step 4) is completed, let the aluminum liquid stand for 10 minutes, open the slag removal door of the holding furnace to remove the slag, and clean the aluminum slag floating on the surface of the aluminum liquid.

[0052] 6) Composition adjustment: Let the aluminum liquid after steps 4) and 5) stand in the holding furnace for 35 minutes, then take samples for analysis. If the element content deviates, make adjustments to confirm that the aluminum liquid composition is consistent with the composition in Table 1.

[0053] 7) Off-furnace refining and slag removal: After step 6 is completed, the molten aluminum can be removed from the furnace when the temperature reaches 740°C. The molten aluminum exits the holding furnace and passes through the launder for online degassing and two-stage filtration. It then undergoes off-furnace refining and further degassing and slag removal (ceramic filter plates at 40 PPI). Al-Ti-B wire is then added to the molten aluminum in the aluminum alloy casting launder via a wire feeder (at a rate of 90 cm / min). Degassing requirements are shown in Table 2.

[0054] Table 2 Degassing requirements

[0055] 8) Continuous casting: Step 7) The clean aluminum liquid after re-refining enters the upper ladle and flows into the lower ladle through the guide pipe for continuous casting. The ladle temperature is controlled at 690-700℃. The horizontal casting method is used for casting under nitrogen conditions of 0.3 standard atmospheric pressure (1 standard atmospheric pressure is 101KPa). The temperature zones that the aluminum liquid enters in sequence are the crystallization section temperature zone (zone 1), the fixed crystal section temperature zone (zone 2), the weak cooling section temperature zone (zone 3), and the strong cooling section temperature zone (zone 4). Figure 2 As shown, the temperature of each zone is: Zone 1: a: 732-740℃; b: 718-725℃; c: 708-715℃; Zone 2: d: 722-738℃; e: 714-719℃; f: 705-709℃; Zone 3: G: 715-716℃; H: 707-714℃; I: 702-704℃; Zone 4: J: 708-712℃; K: 702-706℃; M: 695-700℃; Among them, the grain orientation control device in each temperature zone is as follows Figure 3 As shown, it includes a low thermal conductivity ceramic mold shell 1 of the furnace lining insulation material, an atmosphere furnace 2, a directional baffle 4, and a heat conduction layer 6. The low thermal conductivity ceramic mold shell 1 of the furnace lining insulation material and the atmosphere furnace 2 are sealed. Under the action of nitrogen 8, the (melt) 3 is cast into an ingot 7 in the directional crystallization zone 5.

[0056] At the same time, according to the diameter range of the drawn single wire, the crystallization wheel speed is adjusted to 1.5 rpm, the casting cooling water temperature is 30°C, the total cooling water pressure is 0.30 MPa, and the temperature of the billet from the crystallization wheel to the approach bridge is 500°C.

[0057] 9) Continuous Rolling: The ingot produced in step 8) is straightened and heated, maintaining a temperature of 520-540°C before rolling. During the rolling process, an emulsion (14% concentration, 65°C, and 0.25 MPa) is used to lubricate and cool the rolls and aluminum rod. The resulting high-strength aluminum alloy rod has a diameter of 9.5 mm, and the final rolling temperature is controlled below 300°C.

[0058] 10) Aluminum rod quenching: Use water or dilute emulsion to quench the high-strength aluminum alloy rod coming out of the rolling mill - rapid cooling treatment, control the surface temperature of the aluminum rod ≤ 70℃ to ensure the strength of the aluminum rod; quenching should be carried out in zones, that is, quenching in order through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, and quenching zone 5, such as Figure 4 The conditions of each quenching zone are shown in Table 3.

[0059] Table 3 Temperature and cooling water pressure of each quenching zone (pressure expressed in terms of pressure)

[0060] 11) Cleaning of aluminum rod: Before the aluminum rod enters the take-up frame (or winding reel), use compressed air to blow away the water on the surface of the aluminum rod to keep the aluminum rod clean and dry.

[0061] 12) Natural cooling: The aluminum alloy rod obtained in step 11) is placed on the site for natural cooling. The cooling time shall not be less than 24 hours.

[0062] 13) Drawing and directional graining: The drawing process should adopt pre-drawing followed by formal drawing, with a drawing speed of 15m / s, a cross-sectional change rate of 20% per pass, and the diameter of the drawn finished aluminum wire is 2.4mm or 3.85mm.

[0063] 14) Recrystallization or recrystallization: The drawn aluminum alloy single wire is placed at 115℃ for 5 hours for constant temperature treatment, and then placed at room temperature for 20 hours before the next processing step.

[0064] 15) Double-stage aging treatment: The material treated in 14) is placed in a heat treatment device for aging treatment: The first aging treatment process: 155℃ / 2+6+1h (heating + insulation + power off insulation); Second aging treatment process: 175℃ / 1+4h (heating + insulation).

[0065] Example 2 This embodiment is the same as embodiment 1, except for the elemental composition. The specific elemental composition is shown in Table 1.

[0066] Example 3 This embodiment is the same as embodiment 1, except for the elemental composition. The specific elemental composition is shown in Table 1.

[0067] Comparative Example 1 This embodiment is the same as embodiment 1, except that: (1) the continuous casting is a conventional method, i.e., the casting temperature is 714-719°C; and (2) step 14) tempering and recrystallization is not performed. The specific steps are as follows: 1) Raw material selection and smelting: Inspect the raw materials, select Al99.70 aluminum ingots, put them into the aluminum melting furnace for smelting, control the aluminum liquid temperature in the furnace at 760℃, and use nitrogen (N2 ≥ 99.99% or more) as the gas protection in the furnace.

[0068] 2) Analysis of aluminum liquid composition: The smelted aluminum liquid is transferred to a holding furnace, stirred evenly, and then sampled for rapid analysis using a direct reading spectrometer to detect the contents of Al, Si, Fe, Cu, Mg, B, Ti, La, and Ce in the solution.

[0069] 3) Alloying treatment: Based on the spectral test results in step 2) and the composition in Table 1, calculate the amount of magnesium ingot, aluminum silicon, aluminum iron, aluminum copper, aluminum rare earth, aluminum boron, and aluminum titanium master alloy to be added. When the temperature of the aluminum liquid in the holding furnace is controlled at 750°C, add the corresponding master alloy and stir manually and electromagnetically for 30 minutes to make the aluminum liquid composition fully uniform.

[0070] 4) Furnace refining: After completing step 3), when the aluminum liquid temperature reaches 750°C, use 99.999% high-purity nitrogen as a carrier to pass a high-efficiency powder spray refining agent into the melt in the holding furnace for refining to achieve degassing and impurity removal of the aluminum liquid. During refining, the refining agent blowing speed and nitrogen pressure are controlled to keep the refining time within 30 minutes and the nitrogen pressure within 15KPa.

[0071] 5) Slag removal: After step 4) is completed, let the aluminum liquid stand for 10 minutes, open the slag removal door of the holding furnace to remove the slag, and clean the aluminum slag floating on the surface of the aluminum liquid.

[0072] 6) Composition adjustment: Let the aluminum liquid after steps 4) and 5) stand in the holding furnace for 35 minutes, then take samples for analysis. If the element content deviates, make adjustments to confirm that the aluminum liquid composition is consistent with the composition in Table 1.

[0073] 7) Refining and slag removal outside the furnace: After step 6) is completed, when the aluminum liquid temperature reaches 740℃, it can be taken out of the furnace. The aluminum liquid comes out of the holding furnace and passes through the launder for online degassing and two-stage filtration, and then undergoes refining outside the furnace. It is degassed and deslaged again (ceramic filter plate 40PPI), and Al-Ti-B wire is added to the aluminum melt in the aluminum alloy casting launder through a wire feeder.

[0074] 8) Continuous Casting: After step 7), the clean aluminum liquid is refined again and enters the upper ladle, which flows into the lower ladle through the guide pipe for continuous casting. The ladle temperature is controlled at 690-700℃. The horizontal casting method is used for casting, and the casting temperature is 714-719℃. At the same time, according to the diameter range of the drawn single wire, the crystallization wheel speed is adjusted to 1.5 rpm, the casting cooling water temperature is 30°C, the total cooling water pressure is 0.30 MPa, and the temperature of the billet from the crystallization wheel to the approach bridge is 500°C.

[0075] 9) Continuous Rolling: The ingot produced in step 8) is straightened and heated, maintaining a temperature of 520-540°C before rolling. During the rolling process, an emulsion (14% concentration, 65°C, and 0.25 MPa) is used to lubricate and cool the rolls and aluminum rod. The resulting high-strength aluminum alloy rod has a diameter of 9.5 mm, and the final rolling temperature is controlled below 300°C.

[0076] 10) Quenching of aluminum rods: Use water or dilute emulsion to quench the high-strength aluminum alloy rods coming out of the rolling mill - rapid cooling treatment, control the surface temperature of the aluminum rods ≤ 70 ° C to ensure the strength of the aluminum rods; quenching should be carried out in zones, that is, quenching in order through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, quenching zone 5, such as Figure 4 The conditions of each quenching zone are shown in Table 3.

[0077] 11) Cleaning of aluminum rod: Before the aluminum rod enters the take-up frame (or winding reel), use compressed air to blow away the water on the surface of the aluminum rod to keep the aluminum rod clean and dry.

[0078] 12) Natural cooling: The aluminum alloy rod obtained in step 11) is placed on the site for natural cooling. The cooling time shall not be less than 24 hours.

[0079] 13) Drawing and directional graining: The drawing process should adopt pre-drawing followed by formal drawing, with a drawing speed of 15m / s, a cross-sectional change rate of 20% per pass, and the diameter of the drawn finished aluminum wire is 2.4mm or 3.85mm.

[0080] 14) Double-stage aging treatment: The material after 13) is placed in a heat treatment device for aging treatment: The first aging treatment process: 155℃ / 2+6+1h (heating + insulation + power off insulation); Second aging treatment process: 175℃ / 1+4h (heating + insulation).

[0081] Comparative Example 2 This embodiment is the same as embodiment 1, except that the continuous casting is a conventional method, that is, the casting temperature is 714-719°C.

[0082] The specific steps are as follows: 1) Raw material selection and smelting: Inspect the raw materials, select Al99.70 aluminum ingots, put them into the aluminum melting furnace for smelting, control the aluminum liquid temperature in the furnace at 760℃, and use nitrogen (N2 ≥ 99.99% or more) as the gas protection in the furnace.

[0083] 2) Analysis of aluminum liquid composition: The smelted aluminum liquid is transferred to a holding furnace, stirred evenly, and then sampled for rapid analysis using a direct reading spectrometer to detect the contents of Al, Si, Fe, Cu, Mg, B, Ti, La, and Ce in the solution.

[0084] 3) Alloying treatment: Based on the spectral test results in step 2) and the composition in Table 1, calculate the amount of magnesium ingot, aluminum silicon, aluminum iron, aluminum copper, aluminum rare earth, aluminum boron, and aluminum titanium master alloy to be added. When the temperature of the aluminum liquid in the holding furnace is controlled at 750°C, add the corresponding master alloy and stir manually and electromagnetically for 30 minutes to make the aluminum liquid composition fully uniform.

[0085] 4) Furnace refining: After completing step 3), when the aluminum liquid temperature reaches 750°C, use 99.999% high-purity nitrogen as a carrier to pass a high-efficiency powder spray refining agent into the melt in the holding furnace for refining to achieve degassing and impurity removal of the aluminum liquid. During refining, the refining agent blowing speed and nitrogen pressure are controlled to keep the refining time within 30 minutes and the nitrogen pressure within 15KPa.

[0086] 5) Slag removal: After step 4) is completed, let the aluminum liquid stand for 10 minutes, open the slag removal door of the holding furnace to remove the slag, and clean the aluminum slag floating on the surface of the aluminum liquid.

[0087] 6) Composition adjustment: Let the aluminum liquid after steps 4) and 5) stand in the holding furnace for 35 minutes, then take samples for analysis. If the element content deviates, make adjustments to confirm that the aluminum liquid composition is consistent with the composition in Table 1.

[0088] 7) Refining and slag removal outside the furnace: After step 6) is completed, when the aluminum liquid temperature reaches 740℃, it can be taken out of the furnace. The aluminum liquid comes out of the holding furnace and passes through the launder for online degassing and two-stage filtration, and then undergoes refining outside the furnace. It is degassed and deslaged again (ceramic filter plate 40PPI), and Al-Ti-B wire is added to the aluminum melt in the aluminum alloy casting launder through a wire feeder.

[0089] 8) Continuous Casting: After step 7), the clean aluminum liquid is refined again and enters the upper ladle, which flows into the lower ladle through the guide pipe for continuous casting. The ladle temperature is controlled at 690-700℃. The horizontal casting method is used for casting, and the casting temperature is 714-719℃. At the same time, according to the diameter range of the drawn single wire, the crystallization wheel speed is adjusted to 1.5 rpm, the casting cooling water temperature is 30°C, the total cooling water pressure is 0.30 MPa, and the temperature of the billet from the crystallization wheel to the approach bridge is 500°C.

[0090] 9) Continuous Rolling: The ingot produced in step 8) is straightened and heated, maintaining a temperature of 520-540°C before rolling. During the rolling process, an emulsion (14% concentration, 65°C, and 0.25 MPa) is used to lubricate and cool the rolls and aluminum rod. The resulting high-strength aluminum alloy rod has a diameter of 9.5 mm, and the final rolling temperature is controlled below 300°C.

[0091] 10) Quenching of aluminum rods: Use water or dilute emulsion to quench the high-strength aluminum alloy rods coming out of the rolling mill - rapid cooling treatment, control the surface temperature of the aluminum rods ≤ 70 ° C to ensure the strength of the aluminum rods; quenching should be carried out in zones, that is, quenching in order through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, quenching zone 5, such as Figure 4 The conditions of each quenching zone are shown in Table 3.

[0092] 11) Cleaning of aluminum rod: Before the aluminum rod enters the take-up frame (or winding reel), use compressed air to blow away the water on the surface of the aluminum rod to keep the aluminum rod clean and dry.

[0093] 12) Natural cooling: The aluminum alloy rod obtained in step 11) is placed on the site for natural cooling. The cooling time shall not be less than 24 hours.

[0094] 13) Drawing and directional graining: The drawing process should adopt pre-drawing followed by formal drawing, with a drawing speed of 15m / s, a cross-sectional change rate of 20% per pass, and the diameter of the drawn finished aluminum wire is 2.4mm or 3.85mm.

[0095] 14) Recrystallization or recrystallization: The drawn aluminum alloy single wire is placed at 115℃ for 5 hours for constant temperature treatment, and then placed at room temperature for 20 hours before the next processing step.

[0096] 15) Double-stage aging treatment: The material treated in 14) is placed in a heat treatment device for aging treatment: The first aging treatment process: 155℃ / 2+6+1h (heating + insulation + power off insulation); Second aging treatment process: 175℃ / 1+4h (heating + insulation).

[0097] Comparative Example 3 This embodiment is the same as embodiment 1, except that step 14) tempering and recrystallization is not performed. The specific steps are as follows: 1) Raw material selection and smelting: Inspect the raw materials, select Al99.70 aluminum ingots, put them into the aluminum melting furnace for smelting, control the aluminum liquid temperature in the furnace at 760℃, and use nitrogen (N2 ≥ 99.99% or more) as the gas protection in the furnace.

[0098] 2) Analysis of aluminum liquid composition: The smelted aluminum liquid is transferred to a holding furnace, stirred evenly, and then sampled for rapid analysis using a direct reading spectrometer to detect the contents of Al, Si, Fe, Cu, Mg, B, Ti, La, and Ce in the solution.

[0099] 3) Alloying treatment: Based on the spectral test results in step 2) and the composition in Table 1, calculate the amount of magnesium ingot, aluminum silicon, aluminum iron, aluminum copper, aluminum rare earth, aluminum boron, and aluminum titanium master alloy to be added. When the temperature of the aluminum liquid in the holding furnace is controlled at 750°C, add the corresponding master alloy and stir manually and electromagnetically for 30 minutes to make the aluminum liquid composition fully uniform.

[0100] 4) Furnace refining: After completing step 3), when the aluminum liquid temperature reaches 750°C, use 99.999% high-purity nitrogen as a carrier to pass a high-efficiency powder spray refining agent into the melt in the holding furnace for refining to achieve degassing and impurity removal of the aluminum liquid. During refining, the refining agent blowing speed and nitrogen pressure are controlled to keep the refining time within 30 minutes and the nitrogen pressure within 15KPa.

[0101] 5) Slag removal: After step 4) is completed, let the aluminum liquid stand for 10 minutes, open the slag removal door of the holding furnace to remove the slag, and clean the aluminum slag floating on the surface of the aluminum liquid.

[0102] 6) Composition adjustment: Let the aluminum liquid after steps 4) and 5) stand in the holding furnace for 35 minutes, then take samples for analysis. If the element content deviates, make adjustments to confirm that the aluminum liquid composition is consistent with the composition in Table 1.

[0103] 7) Refining and slag removal outside the furnace: After step 6) is completed, when the aluminum liquid temperature reaches 740℃, it can be taken out of the furnace. The aluminum liquid comes out of the holding furnace and passes through the launder for online degassing and two-stage filtration, and then undergoes refining outside the furnace. It is degassed and deslaged again (ceramic filter plate 40PPI), and Al-Ti-B wire is added to the aluminum melt in the aluminum alloy casting launder through a wire feeder.

[0104] 8) Continuous casting: Step 7) The clean aluminum liquid after re-refining enters the upper ladle and flows into the lower ladle through the guide pipe for continuous casting. The ladle temperature is controlled at 690~700℃ and horizontal casting is adopted. The temperature zones that the aluminum liquid enters in sequence are the crystallization section temperature zone (zone 1), the fixed crystal section temperature zone (zone 2), the weak cooling section temperature zone (zone 3), and the strong cooling section temperature zone (zone 4). Figure 2 As shown, the temperature of aluminum liquid in each zone is: Zone 1: a: 732-740℃; b: 718-725℃; c: 708-715℃; Zone 2: d: 722-738℃; e: 714-719℃; f: 705-709℃; Zone 3: G: 715-716℃; H: 707-714℃; I: 702-704℃; Zone 4: J: 708-712℃; K: 702-706℃; M: 695-700℃.

[0105] At the same time, according to the diameter range of the drawn single wire, the crystallization wheel speed is adjusted to 1.5 rpm, the casting cooling water temperature is 30°C, the total cooling water pressure is 0.30 MPa, and the temperature of the billet from the crystallization wheel to the approach bridge is 500°C.

[0106] 9) Continuous Rolling: The ingot produced in step 8) is straightened and heated, maintaining a temperature of 520-540°C before rolling. During the rolling process, an emulsion (14% concentration, 65°C, and 0.25 MPa) is used to lubricate and cool the rolls and aluminum rod. The resulting high-strength aluminum alloy rod has a diameter of 9.5 mm, and the final rolling temperature is controlled below 300°C.

[0107] 10) Quenching of aluminum rods: Use water or dilute emulsion to quench the high-strength aluminum alloy rods coming out of the rolling mill - rapid cooling treatment, control the surface temperature of the aluminum rods ≤ 70 ° C to ensure the strength of the aluminum rods; quenching should be carried out in zones, that is, quenching in order through quenching zone 1, quenching zone 2, quenching zone 3, quenching zone 4, quenching zone 5, such as Figure 4 The conditions of each quenching zone are shown in Table 3.

[0108] 11) Cleaning of aluminum rod: Before the aluminum rod enters the take-up frame (or winding reel), use compressed air to blow away the water on the surface of the aluminum rod to keep the aluminum rod clean and dry.

[0109] 12) Natural cooling: The aluminum alloy rod obtained in step 11) is placed on the site for natural cooling. The cooling time shall not be less than 24 hours.

[0110] 13) Drawing and directional graining: The drawing process should adopt pre-drawing followed by formal drawing, with a drawing speed of 15m / s, a cross-sectional change rate of 20% per pass, and the diameter of the drawn finished aluminum wire is 2.4mm or 3.85mm.

[0111] 14) Double-stage aging treatment: The material after 13) is placed in a heat treatment device for aging treatment: The first aging treatment process: 155℃ / 2+6+1h (heating + insulation + power off insulation); Second aging treatment process: 175℃ / 1+4h (heating + insulation).

[0112] The elemental compositions of Examples 1-3 are shown in Table 1.

[0113] Table 1 Elemental composition of Examples 1-3 (%)

[0114] The performance of the aluminum rods and aluminum wires prepared in the examples and comparative examples was tested according to the following standards: GB / T 3048.2-2007 Test methods for electrical properties of wires and cables - Part 2: Resistivity test for metallic conductor materials (IEC 60648:1974.MOD); GB / T 4909.2 Bare Wire Test Methods Part 2: Dimension Measurement; GB / T 4909.3 Bare wire test methods Part 3: Tensile test; The test results are shown in Table 4.

[0115] Table 4 Properties of aluminum rods and aluminum wires prepared in various embodiments and comparative examples

[0116] Table 4 shows that the aluminum alloy materials prepared in Examples 1-3 have high tensile strength and low resistivity. Comparison of Comparative Examples 1-3 with Example 1 shows that when neither directional crystallization nor tempering and recrystallization is performed during the continuous casting process, or when neither step is performed, the mechanical properties (tensile strength and elongation) significantly decrease, while the resistivity increases. This demonstrates that the aluminum alloy material provided by the present invention achieves high tensile strength and low resistivity by controlling the ultraslenderization of the metal grain structure through directional crystallization, tempering and recrystallization, and two-stage aging treatment based on its elemental composition, thereby achieving axial dislocation texture strengthening.

[0117] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. An ultra-high strength, high conductivity, elongated grain aluminum alloy material, characterized by: According to the percentage by mass, the following elements Composition: Si: 0.56-0.75%, Fe: 0.2-0.5%, Cu: 0.005-0.15%, Mg: 0.45-0.85%, RE: 0.1-0.25%, B: 0.005-0.03%, Ti: 0.001-0.02%, the balance is aluminum; Among them, RE is a rare earth element.

2. The ultra-high strength, high conductivity, elongated grain aluminum alloy material according to claim 1, characterized in that: RE is La and Ce, and the mass ratio of La to Ce is 1:2.0-2.

5.

3. A method for preparing the ultra-high strength, high conductivity, elongated grain aluminum alloy material according to claim 1, characterized in that: It includes the process of smelting, alloying, refining, continuous casting, continuous rolling, quenching, drawing, tempering recrystallization and aging treatment in sequence; The continuous casting process involves continuous casting in an inert atmosphere below atmospheric pressure at a temperature of 690-740°C. During the continuous casting process, the molten aluminum sequentially enters several temperature zones, and the average temperature of each temperature zone gradually decreases as the aluminum flows. The temperature within each temperature zone also gradually decreases as the aluminum flows. Furthermore, between two adjacent temperature zones, the outlet temperature of the upstream temperature zone is lower than the inlet temperature of the downstream temperature zone. The process of tempering and recrystallization is as follows: the drawn aluminum alloy single wire is placed at a temperature of 110-120°C for constant temperature treatment, and then placed at room temperature for constant temperature treatment.

4. The preparation method according to claim 3, wherein: The temperature zones that the aluminum liquid enters in sequence are the crystallization section temperature zone, the crystal stabilization section temperature zone, the weak cooling section temperature zone, and the strong cooling section temperature zone. Among them, the temperature of the crystallization section temperature zone is 708-740℃, the temperature of the crystal stabilization section temperature zone is 705-738℃, the temperature of the weak cooling section temperature zone is 702-716℃, and the temperature of the strong cooling section temperature zone is 695-712℃. Alternatively, the temperature of the upstream section of the crystallization temperature zone is 732-740°C, the temperature of the midstream section of the crystallization temperature zone is 718-725°C, and the temperature of the downstream section of the crystallization temperature zone is 708-715°C; Alternatively, the temperature of the upstream section of the crystallization temperature zone is 722-738°C, the temperature of the midstream section of the crystallization temperature zone is 714-719°C, and the temperature of the downstream section of the crystallization temperature zone is 705-709°C; Or, the temperature of the upstream section of the weak cooling section temperature zone is 715-716°C, the temperature of the midstream section of the weak cooling section temperature zone is 707-714°C, and the temperature of the downstream section of the weak cooling section temperature zone is 702-704°C; Alternatively, the temperature of the upstream section of the strong cooling section temperature zone is 708-712°C, the temperature of the midstream section of the strong cooling section temperature zone is 702-706°C, and the temperature of the downstream section of the strong cooling section temperature zone is 695-700°C.

5. The preparation method according to claim 3, wherein: During tempering and recrystallization, the constant temperature treatment time is 4-6 hours at a temperature of 110-120°C; Alternatively, during tempering and recrystallization, the constant temperature treatment time at room temperature is 16-24 hours.

6. The preparation method according to claim 3, wherein: The smelting process is as follows: heating and melting the aluminum metal raw material under inert atmosphere; Or, the melting temperature is 750-780°C; Alternatively, the alloying process is as follows: adding a master alloy to the smelted aluminum liquid according to a proportion; Alternatively, the temperature of the alloying treatment is 730-750°C.

7. The preparation method according to claim 3, wherein: The refining includes furnace refining and external refining, and the temperature of furnace refining is 740-760°C; Alternatively, the refining includes furnace refining and external refining, wherein the furnace refining process is as follows: refining the aluminum liquid by adding a refining agent under an inert atmosphere; Alternatively, the refining includes furnace refining and external refining, and after the furnace refining, slag skimming is performed to clean the aluminum slag floating on the surface of the aluminum liquid; Alternatively, the refining includes furnace refining and external refining, wherein the furnace refining is performed until the aluminum liquid temperature reaches 740-760° C., and then external refining is performed; Alternatively, the refining includes in-furnace refining and out-furnace refining, and the out-furnace refining is sequentially performing online degassing and double-stage filtration.

8. The preparation method according to claim 3, wherein: The aluminum alloy rod after continuous rolling is quenched using water or emulsion; Alternatively, the surface temperature of the aluminum alloy rod after continuous rolling is controlled by quenching to be ≤70°C; Alternatively, quenching is performed by partitioning; Alternatively, the steel may be quenched and then naturally cooled before drawing.

9. The preparation method according to claim 3, wherein: The aging treatment is a double-stage aging treatment, and the temperature of the first aging treatment is different from the temperature of the second aging treatment.

10. Use of the ultra-high strength, high conductivity, elongated grain aluminum alloy material according to claim 1 or 2 in overhead conductors or overhead insulated cables.

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