Aluminum material, directional solidification method, and wire

Abstract

This invention relates to an aluminum material, a directional solidification method, and wire, belonging to the field of aluminum materials. The aluminum material has a grain orientation concentration ≥ 2.22, a post-rolling strength ≥ 125 MPa, and an electrical conductivity ≥ 60.1% IACS. The preparation process includes: applying a spiral magnetic field to the aluminum melt and holding it at a preset temperature for a predetermined time, followed by solidification using a downward pulling method to obtain the aluminum material; the magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the aluminum melt; the direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt; the spiral magnetic field rotates around the aluminum melt; the magnetic field strength of the spiral magnetic field is 20-45 mT; and the downward pulling speed of solidification is 30-200 μm / s. The aluminum material provided by this invention, through the synergistic control of the magnetic field and solidification parameters, achieves purification and texture optimization in one step, effectively controlling the preferred growth orientation and concentration of grains, providing an efficient and controllable process route for preparing pure aluminum materials with both high electrical conductivity and high mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of aluminum materials, specifically to an aluminum material, a directional solidification method, and wire, and more particularly to an aluminum material, a directional solidification method, and wire prepared using a spiral magnetic field-assisted directional solidification. Background Technology

[0002] Currently, ordinary pure aluminum rolled plates have relatively weak performance and cannot directly support the needs of high-end applications. This problem is particularly prominent in actual production and use.

[0003] In traditional preparation processes, impurity removal and grain control are key challenges. Commonly used impurity removal methods such as gravity sedimentation and filtration have very low efficiency in removing harmful impurities such as Fe and Si from the top sample.

[0004] Although directional solidification can be used to remove iron from the top sample, CN1162557C discloses a continuous liquid exchange directional solidification continuous casting purification method for primary aluminum. It uses a continuous liquid exchange device and a directional solidification continuous casting device. After melting the primary aluminum in the melting and holding furnace, the crystallizer is heated to a temperature exceeding the melting point of aluminum by a heating element. The crystal rod is placed in the crystallizer, and the aluminum liquid is introduced into the flow channel. The liquid exchange is carried out at the solid-liquid interface of the casting rod by an electromagnetic pump and a stirrer. The continuous casting speed is gradually increased to a stable stage before purification begins.

[0005] However, directional solidification alone is not only ineffective at separating dispersed impurities, but also prone to generating coarse grains, directly limiting the overall performance of the material. Even more disadvantageous is that material strength often requires subsequent heat treatment to meet standards, which increases production costs, lengthens the production cycle, and affects efficiency and application suitability. Summary of the Invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a method for directional solidification of aluminum materials to solve the problems of difficult removal of dispersed impurities and coarse grains during the solidification process of aluminum materials.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides an aluminum material having a grain orientation concentration ≥2.22, a post-rolling strength ≥125MPa, and an electrical conductivity ≥60.1%IACS;

[0009] The preparation process of the aluminum material includes:

[0010] A spiral magnetic field is applied to the molten aluminum and held at a preset temperature for a predetermined time, after which the aluminum material is solidified using a downward drawing method.

[0011] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum.

[0012] The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt.

[0013] The spiral magnetic field rotates around the molten aluminum;

[0014] The magnetic field strength of the spiral magnetic field is 20-45 mT;

[0015] The solidification pull-down speed is 30-200 μm / s.

[0016] The aluminum material provided by this invention achieves purification and texture optimization in one step through the coordinated control of magnetic field and solidification parameters during the preparation process. Directional solidification is carried out under the action of a spiral magnetic field, and the downward pull speed of solidification is controlled at the same time. While purifying the melt, the preferred growth orientation and concentration of grains are effectively controlled. At the same time, the magnetic field strength is controlled to control the grain size and improve the impurity removal effect, thus realizing the preparation of a pure aluminum material with both high conductivity and high mechanical properties.

[0017] Secondly, the present invention provides a method for directional solidification of aluminum materials, the method comprising:

[0018] A spiral magnetic field is applied to the molten aluminum and held at a preset temperature for a predetermined time, after which the aluminum material is solidified using a downward drawing method.

[0019] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum.

[0020] The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt.

[0021] The spiral magnetic field rotates around the molten aluminum;

[0022] The magnetic field strength of the spiral magnetic field is 20-45 mT;

[0023] The solidification pull-down speed is 30-200 μm / s.

[0024] As a preferred embodiment of the present invention, the magnetic field strength of the spiral magnetic field is 30-45mT, excluding 30mT.

[0025] Preferably, the electromagnetic frequency of the spiral magnetic field is 5-15Hz.

[0026] As a preferred embodiment of the present invention, the insulation temperature is 900-950℃.

[0027] Preferably, the preset time is 1800-3600s.

[0028] As a preferred embodiment of the present invention, the aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere.

[0029] As a preferred technical solution of the present invention, the aluminum raw material includes: block aluminum material and / or granular aluminum material;

[0030] Preferably, the pressure of the protective atmosphere is 300-350 Pa;

[0031] Preferably, the protective atmosphere includes one or a combination of at least two of helium, neon, or argon.

[0032] As a preferred embodiment of the present invention, the melting process includes: heating to a first temperature at a first rate and holding for a first time, and then heating to a second temperature at a second rate and holding for a second time.

[0033] As a preferred embodiment of the present invention, the first rate is 15-25℃ / min;

[0034] Preferably, the first temperature is 490-510℃;

[0035] Preferably, the first heat preservation time is 90-110 seconds.

[0036] As a preferred embodiment of the present invention, the second rate is 15-25℃ / min;

[0037] Preferably, the second temperature is 900-950℃;

[0038] Preferably, the second heat preservation time is 550-600s.

[0039] Thirdly, the present invention provides a wire, which is prepared using aluminum material as described in the first aspect or aluminum material obtained by the directional solidification method described in the second aspect.

[0040] Compared with existing technical solutions, the present invention has the following beneficial effects:

[0041] (1) The aluminum material provided by the present invention combines directional solidification with electromagnetic metallurgy in the preparation process to construct an efficient preparation system. A spiral propulsion magnetic field is applied in the solidification direction, so that the aluminum liquid generates eddies and Lorentz forces under the action of the magnetic field, thereby forming a stable spiral flow and achieving full mixing. This spiral flow brings multiple effects: on the one hand, it significantly enhances the convection of the aluminum liquid, washes away and migrates the Fe element and related intermetallic compound particles precipitated at the solidification front to the enrichment zone at the top of the aluminum melt, and achieves efficient aggregation and removal of harmful impurities; on the other hand, it effectively breaks up the coarse grains that are easily formed in traditional processes, and promotes their refinement and transformation into uniformly distributed equiaxed grains.

[0042] (2) This invention utilizes helical magnetic field-assisted directional solidification technology to achieve multiple active controls over the solidification process, effectively overcoming the limitation of traditional pure aluminum preparation methods that struggle to simultaneously optimize and improve various properties. The electromagnetic stirring effect and Lorentz force generated by the magnetic field can effectively suppress the segregation of impurity elements at the solid-liquid interface, effectively purifying the aluminum melt and reducing the concentration of impurity scattering centers at the source. At the same time, this technology can also actively control the growth orientation of grains, guiding them to preferentially align in a specific direction, ultimately forming a structure with a highly concentrated crystallographic orientation.

[0043] (3) The directional solidification technology provided by this invention can ensure that the grain orientation has a certain degree of concentration, thereby improving the damage of impurities to the integrity and uniformity of the aluminum matrix crystals from the source and reducing the risk of stress concentration during processing. Finally, the pure aluminum rolled plate prepared by this process can obtain good mechanical properties without additional heat treatment, and the comprehensive performance is significantly improved, which can directly meet the needs of high-end application scenarios and effectively break through the dual bottlenecks of traditional processes in terms of performance and efficiency. Attached Figure Description

[0044] Figure 1 This is a grain orientation diagram of the aluminum material obtained in Example 1 of the present invention;

[0045] Figure 2 This is a statistical diagram of the grain orientation of the aluminum material obtained in Example 1 of the present invention;

[0046] Figure 3 This is a grain orientation diagram of the aluminum material obtained in Example 5 of the present invention;

[0047] Figure 4 This is a statistical diagram of the grain orientation of the aluminum material obtained in Example 5 of the present invention;

[0048] Figure 5 This is a grain orientation diagram of the aluminum material obtained in Example 6 of the present invention;

[0049] Figure 6 This is a statistical diagram of the grain orientation of the aluminum material obtained in Example 6 of the present invention;

[0050] Figure 7 This is a grain orientation diagram of the aluminum material obtained in Example 7 of the present invention;

[0051] Figure 8 This is a statistical diagram of the grain orientation of the aluminum material obtained in Example 7 of the present invention.

[0052] The present invention will now be described in further detail. However, the examples described below are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims. Detailed Implementation

[0053] To better illustrate the present invention and facilitate understanding of its technical solutions, typical but non-limiting embodiments of the present invention are as follows:

[0054] Currently, ordinary pure aluminum rolled sheets have relatively weak performance, making it difficult to directly support the demands of high-end applications. This problem is particularly prominent in actual production and use. In traditional preparation processes, impurity removal and grain control are key challenges. Commonly used impurity removal methods such as gravity sedimentation and filtration have very low efficiency in removing harmful impurities such as Fe and Si from the top sample. Although directional solidification can remove iron from the top sample, this single technique not only fails to effectively separate dispersed impurities but also easily generates coarse grains, directly limiting the overall performance of the material. Even more disadvantageous is that the material's mechanical properties often require subsequent heat treatment to meet standards, increasing production costs and lengthening the production cycle, affecting efficiency and application adaptability. Therefore, this invention optimizes the solidification process by synergistically controlling the magnetic field and solidification parameters to achieve purification and texture optimization in one step. This provides an efficient and controllable process route for preparing pure aluminum materials with both high conductivity and high mechanical properties, as detailed below:

[0055] I. This embodiment provides an aluminum material with a grain orientation concentration ≥2.22, a post-rolling strength ≥125MPa, and an electrical conductivity ≥60.1%IACS;

[0056] The preparation process of the aluminum material includes:

[0057] A spiral magnetic field is applied to the molten aluminum and held at a preset temperature for a predetermined time, after which the aluminum material is solidified using a downward drawing method.

[0058] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum.

[0059] The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt.

[0060] The spiral magnetic field rotates around the molten aluminum;

[0061] The magnetic field strength of the spiral magnetic field is 20-45 mT;

[0062] The solidification pull-down speed is 30-200 μm / s.

[0063] Furthermore, the grain size of the aluminum material is ≤676μm, and the crystal orientation can be 104 or 001.

[0064] II. This embodiment provides a method for directional solidification of aluminum, the method comprising:

[0065] A spiral magnetic field is applied to the molten aluminum and it is kept at a preset temperature for a predetermined time. Then, the aluminum material is solidified by the downward drawing method.

[0066] The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere.

[0067] The aluminum raw materials include: block aluminum materials and / or granular aluminum materials, which can be selected according to the conventional smelting requirements in this field.

[0068] In this invention, the aluminum material can be selected as electrolytic aluminum or the like. For example, electrolytic aluminum with a purity of ≥99.85% can be used, wherein the impurity elements are V, Ti, Fe, Si, Zn, Mg, Mn and Ga, and the Fe element mass percentage content is >0.06%.

[0069] In this invention, the axis of the aluminum melt refers to the axis of the aluminum melt in a container placed in the solidification equipment, which is parallel to the axis of the aluminum melt in a certain shape. The specific shape is related to the shape of the container and the content of aluminum melt in the container.

[0070] In this invention, the raw materials are arranged according to conventional requirements in the art during melting, such as cutting aluminum ingots into 10cm equidistant metal blocks using a saw; placing the equidistant metal blocks vertically with a vertical height of 10cm; cutting metal rods with a diameter of 15mm from the metal ingots using wire cutting; cleaning the oxide scale on the surface of the cut metal rods with sandpaper; cleaning the surface of the abrasive particles using an ultrasonic cleaner; and placing the dried aluminum rods into a crucible.

[0071] The pressure of the protective atmosphere is 300-350 Pa, for example, it can be 300 Pa, 305 Pa, 310 Pa, 315 Pa, 320 Pa, 325 Pa, 330 Pa, 335 Pa, 340 Pa, 345 Pa or 350 Pa, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0072] The protective atmosphere includes one or a combination of at least two of helium, neon, or argon.

[0073] The melting process includes: heating to a first temperature at a first rate and holding for a first time, and then heating to a second temperature at a second rate and holding for a second time.

[0074] The first rate is 15-25℃ / min, for example, it can be 15℃ / min, 16℃ / min, 17℃ / min, 18℃ / min, 19℃ / min, 20℃ / min, 21℃ / min, 22℃ / min, 23℃ / min, 24℃ / min or 25℃ / min, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0075] The first temperature is 490-510℃, for example, it can be 490℃, 492℃, 494℃, 496℃, 498℃, 500℃, 502℃, 504℃, 506℃, 508℃ or 510℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0076] The first heat preservation time is 90-110s, for example, it can be 90s, 92s, 94s, 96s, 98s, 100s, 102s, 104s, 106s, 108s or 110s, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0077] The second rate is 15-25℃ / min, for example, it can be 15℃ / min, 16℃ / min, 17℃ / min, 18℃ / min, 19℃ / min, 20℃ / min, 21℃ / min, 22℃ / min, 23℃ / min, 24℃ / min or 25℃ / min, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0078] The second temperature is 900-950℃, for example, it can be 900℃, 905℃, 910℃, 915℃, 920℃, 925℃, 930℃, 935℃, 940℃, 945℃ or 950℃, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0079] The second heat preservation time is 550-600s, for example, it can be 550s, 555s, 560s, 565s, 570s, 575s, 580s, 585s, 590s, 595s or 600s, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0080] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum.

[0081] The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt.

[0082] The spiral magnetic field rotates around the molten aluminum.

[0083] The magnetic field strength of the spiral magnetic field is 20-45 mT, for example, it can be 20 mT, 22.5 mT, 25 mT, 27.5 mT, 30 mT, 32.5 mT, 35 mT, 37.5 mT, 40 mT, 42.5 mT or 45 mT, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable. Preferably, it is 30-45 mT, excluding 30 mT.

[0084] The electromagnetic frequency of the spiral magnetic field is 5-15Hz, for example, it can be 5Hz, 6Hz, 7Hz, 8Hz, 9Hz, 10Hz, 11Hz, 12Hz, 13Hz, 14Hz or 15Hz, but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0085] The insulation temperature is 900-950℃, for example, it can be 900℃, 905℃, 910℃, 915℃, 920℃, 925℃, 930℃, 935℃, 940℃, 945℃ or 950℃, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0086] The preset time is 1800-3600s, for example, it can be 1800s, 1980s, 2160s, 2340s, 2520s, 2700s, 2880s, 3060s, 3240s, 3420s or 3600s, but is not limited to the listed values. Other unlisted values ​​within this range also meet the requirements.

[0087] The solidification pull-down speed is 30-200 μm / s, for example, it can be 30 μm / s, 47 μm / s, 64 μm / s, 81 μm / s, 98 μm / s, 115 μm / s, 132 μm / s, 149 μm / s, 166 μm / s, 183 μm / s or 200 μm / s, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also acceptable.

[0088] In this invention, the top of the sample rod after directional solidification is removed because the elemental bias at the top will be formed under the helical magnetic field, and a large number of elements will accumulate at the top, while the composition below the accumulation end is more uniform and the performance is stable. The specific removal length can be reasonably selected according to the actual requirements.

[0089] In this invention, the solidified aluminum material can be further rolled to prepare high-strength pure aluminum. The rolling process is exemplarily as follows: the rolling temperature is selected as room temperature (20-40℃), the rolling amount is 10-15% each time, the total rolling amount is 90-95%, and the rolling ends when the sample thickness is reduced to 1mm.

[0090] In this invention, by controlling the strength of the spiral magnetic field and the downward pull speed during the solidification process of aluminum, the growth rate of the crystal and the solidification rate can be matched during the solidification process. This can significantly optimize the size and growth orientation of the grains, and produce aluminum with concentrated orientation. This results in a qualitative improvement in the conductivity of the aluminum. Through further rolling, aluminum with even better performance can be produced.

[0091] III. This embodiment provides a wire, which is prepared using aluminum or aluminum obtained by directional solidification.

[0092] In this invention, when the obtained aluminum material is used as a wire, it has a superior electrical conductivity, which can significantly reduce energy consumption and improve energy utilization.

[0093] IV. To illustrate the superior properties of the aluminum material obtained by the directional solidification method of the present invention, the following examples are provided:

[0094] In the following examples, the aluminum material used is 99.85 grade aluminum, with impurities Fe and Si having a mass percentage content of 0.066% and 0.0018%, respectively.

[0095] Example 1

[0096] This embodiment provides a method for directional solidification of aluminum, the method comprising:

[0097] A spiral magnetic field is applied to the molten aluminum and it is kept at a preset temperature for a predetermined time. Then, the aluminum material is solidified by the downward drawing method.

[0098] The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere; the aluminum raw materials include: block aluminum material (height × diameter: 10cm × 15mm).

[0099] The pressure of the protective atmosphere is 340 Pa; the protective atmosphere is argon.

[0100] The melting process includes: heating to a first temperature at a first rate and holding at a first temperature, then heating to a second temperature at a second rate and holding at a second temperature; the first rate is 20°C / min; the first temperature is 505°C; the first holding time is 105s; the second rate is 20°C / min; the second temperature is 940°C; and the second holding time is 560s.

[0101] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the aluminum melt; the direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt; the spiral magnetic field rotates around the aluminum melt; the magnetic field strength of the spiral magnetic field is 45mT; the electromagnetic frequency of the spiral magnetic field is 10Hz.

[0102] The insulation temperature is 940℃;

[0103] The preset time is 2000s;

[0104] The solidification pull-down speed is 30 μm / s.

[0105] Example 2

[0106] This embodiment provides a method for directional solidification of aluminum, the method comprising:

[0107] A spiral magnetic field is applied to the molten aluminum and it is kept at a preset temperature for a predetermined time. Then, the aluminum material is solidified by the downward drawing method.

[0108] The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere; the aluminum raw materials include: block aluminum material (height × diameter: 10cm × 15mm).

[0109] The pressure of the protective atmosphere is 320 Pa; the protective atmosphere is argon.

[0110] The melting process includes: heating to a first temperature at a first rate and holding at a first temperature, then heating to a second temperature at a second rate and holding at a second temperature; the first rate is 20°C / min; the first temperature is 500°C; the first holding time is 100s; the second rate is 20°C / min; the second temperature is 925°C; and the second holding time is 580s.

[0111] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum; the direction of the magnetic field lines at the top of the molten aluminum is parallel to the axis of the molten aluminum; the spiral magnetic field rotates around the molten aluminum; the magnetic field strength of the spiral magnetic field is 30mT; the electromagnetic frequency of the spiral magnetic field is 15Hz.

[0112] The insulation temperature is 925℃;

[0113] The preset time is 3000s;

[0114] The solidification pull-down speed is 100 μm / s.

[0115] Example 3

[0116] This embodiment provides a method for directional solidification of aluminum, the method comprising:

[0117] A spiral magnetic field is applied to the molten aluminum and it is kept at a preset temperature for a predetermined time. Then, the aluminum material is solidified by the downward drawing method.

[0118] The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere; the aluminum raw materials include: block aluminum material (height × diameter: 10cm × 15mm).

[0119] The pressure of the protective atmosphere is 300 Pa; the protective atmosphere is argon.

[0120] The melting process includes: heating to a first temperature at a first rate and holding at a first temperature, then heating to a second temperature at a second rate and holding at a second temperature; the first rate is 15°C / min; the first temperature is 490°C; the first holding time is 90s; the second rate is 15°C / min; the second temperature is 900°C; and the second holding time is 600s.

[0121] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum; the direction of the magnetic field lines at the top of the molten aluminum is parallel to the axis of the molten aluminum; the spiral magnetic field rotates around the molten aluminum; the magnetic field strength of the spiral magnetic field is 20mT; the electromagnetic frequency of the spiral magnetic field is 5Hz.

[0122] The insulation temperature is 900℃;

[0123] The preset time is 1800;

[0124] The solidification pull-down speed is 150 μm / s.

[0125] Example 4

[0126] This embodiment provides a method for directional solidification of aluminum, the method comprising:

[0127] A spiral magnetic field is applied to the molten aluminum and it is kept at a preset temperature for a predetermined time. Then, the aluminum material is solidified by the downward drawing method.

[0128] The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere; the aluminum raw materials include: block aluminum material (height × diameter: 10cm × 15mm).

[0129] The pressure of the protective atmosphere is 350 Pa; the protective atmosphere is argon.

[0130] The melting process includes: heating to a first temperature at a first rate and holding at a first temperature, then heating to a second temperature at a second rate and holding at a second temperature; the first rate is 25°C / min; the first temperature is 510°C; the first holding time is 110s; the second rate is 25°C / min; the second temperature is 950°C; and the second holding time is 550s.

[0131] The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the aluminum melt; the direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt; the spiral magnetic field rotates around the aluminum melt; the magnetic field strength of the spiral magnetic field is 25mT; the electromagnetic frequency of the spiral magnetic field is 15Hz.

[0132] The insulation temperature is 950℃;

[0133] The preset time is 3600 seconds;

[0134] The solidification pull-down speed is 200 μm / s.

[0135] Example 5

[0136] The only difference from Example 1 is that the solidification pull-down speed is 50 μm / s.

[0137] Example 6

[0138] The only difference from Example 1 is that the solidification pull-down speed is 100 μm / s.

[0139] Example 7

[0140] The only difference from Example 1 is that the solidification pull-down speed is 200 μm / s.

[0141] Example 8

[0142] The only difference from Example 1 is that the magnetic field strength of the spiral magnetic field is 25mT.

[0143] Example 9

[0144] The only difference from Example 1 is that the preset time is 1500s.

[0145] Example 10

[0146] The only difference from Example 1 is that the preset time is 4500s.

[0147] Comparative Example 1

[0148] The only difference from Example 1 is that no helical magnetic field is applied.

[0149] Comparative Example 2

[0150] The only difference from Example 1 is that the magnetic field strength of the spiral magnetic field is 10mT.

[0151] Comparative Example 3

[0152] The only difference from Example 1 is that the magnetic field strength of the spiral magnetic field is 60mT.

[0153] Comparative Example 4

[0154] The only difference from Example 1 is that the solidification pull-down speed is 20 μm / s.

[0155] Comparative Example 5

[0156] The only difference from Example 1 is that the solidification pull-down speed is 300 μm / s.

[0157] The performance of the aluminum materials obtained in the examples and comparative examples was tested and analyzed, as follows:

[0158] After polishing the sample surface, the maximum area was photographed using EBSD technology, and the obtained data was analyzed using AZteCrystal software. Specifically, the microstructure and texture were statistically analyzed using the grain statistics module and the crystal orientation and orientation concentration module in the software, and the grain orientation concentration was obtained.

[0159] Tensioning was performed on a standard tensile specimen with a gauge length of 15 mm and a strain rate of 1 × 10⁻⁶. -3 s -1 The tensile strength after rolling was tested under the specified conditions to obtain the post-rolling strength.

[0160] The conductivity of the samples was tested using a 2008b model instrument to obtain macroscopic electrical performance data;

[0161] The total mass content of iron and silicon in the feed aluminum and the total mass content of iron and silicon in the product were tested by ICP-OES. Then the removal rate of iron and silicon was calculated as follows: (total mass content of iron and silicon in feed aluminum - total mass content of iron and silicon in product) / total mass content of iron and silicon in feed aluminum × 100%.

[0162] Among them, the grain orientation photographs of Examples 1, 5, 6, and 7 are as follows: Figure 1 , Figure 3 , Figure 5 and Figure 7 As shown, the corresponding statistical results are as follows: Figure 2 , Figure 4 , Figure 6 , Figure 8 As shown in Table 1 below, the specific results are detailed.

[0163] Table 1

[0164]

[0165] The rolling process for the performance indicators after rolling includes: selecting room temperature of 25℃, rolling amount of 10% each time, total rolling amount of 90%, until the sample thickness is reduced to 1mm and the rolling process ends.

[0166] As shown in Table 1, the solution provided by this invention utilizes helical magnetic field-assisted directional solidification technology to optimize the solidification structure while achieving physical purification, thereby obtaining excellent comprehensive performance. During the solidification process, the forced convection generated by the helical magnetic field can promote the enrichment of impurity elements with an equilibrium distribution coefficient K < 1 at the solid-liquid interface front and directionally transport them to the end of the ingot, where physical purification can be achieved through subsequent removal.

[0167] Building upon this foundation, the evolution of the solidification structure can be further regulated by precisely controlling the pull-down rate during directional solidification. On one hand, this technique can significantly improve the orientation concentration of grains, forming a strong preferred orientation texture, thereby reducing electron scattering and effectively enhancing the conductivity of the material; simultaneously, it effectively removes impurity elements, further improving the conductivity of the material. On the other hand, it helps to achieve grain refinement and homogenization. When a material possesses both fine grains and a highly consistent grain orientation, it can achieve high mechanical strength through fine grain strengthening and improve conductivity through texture optimization. This overcomes the limitation of traditional materials where strength and conductivity are difficult to achieve simultaneously, realizing the goal of "dual high performance" through synergistic improvement of both. The resulting aluminum material has a grain orientation concentration ≥ 2.22, a post-rolling strength ≥ 125 MPa, and an electrical conductivity ≥ 60.1% IACS. Under the preferred scheme, the aluminum material has a grain orientation concentration ≥ 4.31, a post-rolling strength ≥ 142 MPa, and an electrical conductivity ≥ 61.2% IACS. Among these, the Fe and Si impurity removal rate is ≥ 76.3%, the grain size is ≤ 676 μm, and under the preferred scheme, the grain size is ≤ 560 μm with grain orientations of 104 and 001.

[0168] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0169] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0170] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. An aluminum material, characterized in that, The aluminum material has a grain orientation concentration ≥2.22, a post-rolling strength ≥125MPa, and an electrical conductivity ≥60.1%IACS; The preparation process of the aluminum material includes: A spiral magnetic field is applied to the molten aluminum and held at a preset temperature for a predetermined time, after which the aluminum material is solidified using a downward drawing method. The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum. The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt. The spiral magnetic field rotates around the molten aluminum; The magnetic field strength of the spiral magnetic field is 20-45 mT; The solidification pull-down speed is 30-200 μm / s.

2. A method for directional solidification of aluminum material, characterized in that, The directional solidification method includes: A spiral magnetic field is applied to the molten aluminum and held at a preset temperature for a predetermined time, after which the aluminum material is solidified using a downward drawing method. The magnetic field lines of the spiral magnetic field extend spirally from the bottom to the top of the molten aluminum. The direction of the magnetic field lines at the top of the aluminum melt is parallel to the axis of the aluminum melt. The spiral magnetic field rotates around the molten aluminum; The magnetic field strength of the spiral magnetic field is 20-45 mT; The solidification pull-down speed is 30-200 μm / s.

3. The directional solidification method as described in claim 2, characterized in that, The magnetic field strength of the spiral magnetic field is 30-45 mT, excluding 30 mT; Preferably, the electromagnetic frequency of the spiral magnetic field is 5-15Hz.

4. The directional solidification method as described in claim 2, characterized in that, The insulation temperature is 900-950℃; Preferably, the preset time is 1800-3600s.

5. The directional solidification method as described in claim 2, characterized in that, The aluminum melt is obtained by melting aluminum raw materials under a protective atmosphere.

6. The directional solidification method as described in claim 5, characterized in that, The aluminum raw materials include: block aluminum materials and / or granular aluminum materials; Preferably, the pressure of the protective atmosphere is 300-350 Pa; Preferably, the protective atmosphere includes one or a combination of at least two of helium, neon, or argon.

7. The directional solidification method as described in claim 5, characterized in that, The melting process includes: heating to a first temperature at a first rate and holding for a first time, followed by heating to a second temperature at a second rate and holding for a second time.

8. The directional solidification method as described in claim 7, characterized in that, The first rate is 15-25℃ / min; Preferably, the first temperature is 490-510℃; Preferably, the first heat preservation time is 90-110 seconds.

9. The directional solidification method as described in claim 7, characterized in that, The second rate is 15-25℃ / min; Preferably, the second temperature is 900-950℃; Preferably, the second heat preservation time is 550-600s.

10. A wire, characterized in that, The wire is prepared using the aluminum material as described in claim 1 or the aluminum material obtained by the directional solidification method as described in any one of claims 2-9.

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