Aluminum alloy material, preparation method thereof and aluminum alloy part

Abstract

The invention relates to the technical field of aluminum alloy materials. The invention particularly relates to an aluminum alloy material, a preparation method thereof and an aluminum alloy part. The aluminum alloy material is prepared from the following chemical components in percentage by mass: 0.8 percent to 1.2 percent of Si, 0.8 percent to 1.3 percent of Mg, 0.4 percent to 0.8 percent of Cu, 0.2 percent to 0.7 percent of Mn, 0.1 percent to 0.3 percent of Cr, 0.02 percent to 0.05 percent of Ti, 0 to 0.2 percent of Fe, 0 to 0.05 percent of V, 0 to 0.1 percent of Zr and 95.3 percent to 97.68 percent of Al. Wherein the sum of the mass fraction of Mg in the aluminum alloy material, the mass fraction of Si in the aluminum alloy material and the mass fraction of Cu in the aluminum alloy material is 2%-2.8%; the sum of the mass fraction of Mn in the aluminum alloy material, three times of the mass fraction of V in the aluminum alloy material and two times of the mass fraction of Zr in the aluminum alloy material is 0.4%-0.7%; the yield strength of the aluminum alloy material ranges from 360 MPa to 380 MPa.

Description

Technical Field

[0001] This application relates to the field of aluminum alloy materials technology. Specifically, it relates to aluminum alloy materials and their preparation methods, and aluminum alloy components. Background Technology

[0002] As the automotive industry moves towards lightweighting and enhanced safety, aluminum alloys, with their low density and excellent formability, have become one of the core materials for achieving weight reduction and energy efficiency in automobiles. Currently, apart from a small number of all-aluminum car bodies, aluminum alloy profiles are most widely used in key components such as crash beams, energy-absorbing boxes, door sill beams, and battery pack housings for new energy vehicles. These components directly bear the functions of energy absorption and load transfer during vehicle collisions, thus requiring specific energy absorption characteristics and mechanical properties of the materials.

[0003] Currently, most automotive energy-absorbing aluminum alloy components use 6-series aluminum alloys such as 6005A, 6063, 6061, and 6082, whose yield strength is generally lower than 300MPa. Faced with the ever-increasing demands for collision safety in the automotive industry, their mechanical properties can no longer fully meet the core requirements of energy absorption and structural protection during collisions. Summary of the Invention

[0004] Based on this, this application provides aluminum alloy materials, methods for preparing the same, and aluminum alloy components. The aluminum alloy material of this application has high yield strength and flexural strength, which meets the requirements of high strength and high energy absorption for automotive aluminum alloy components.

[0005] A first aspect of this application provides an aluminum alloy material comprising the following chemical composition by mass fraction: 0.8%~1.2% Si, 0.8%~1.3% Mg, 0.4%~0.8% Cu, 0.2%~0.7% Mn, 0.1%~0.3% Cr, 0.02%~0.05% Ti, 0~0.2% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al.

[0006] The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2% to 2.8%.

[0007] The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.4%~0.7%.

[0008] The yield strength of the aluminum alloy material is 360MPa~380MPa.

[0009] In some embodiments, the ratio of the mass fraction of Mg in the aluminum alloy material to the mass fraction of Si in the aluminum alloy material is 0.9 to 1.1.

[0010] In some embodiments, the aluminum alloy material comprises the following chemical composition by mass fraction: 1%~1.1% Si, 0.9%~1.1% Mg, 0.4%~0.65% Cu, 0.3%~0.7% Mn, 0.15%~0.25% Cr, 0.02%~0.05% Ti, 0.08%~0.15% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al;

[0011] The ratio of the mass fraction of Mg to the mass fraction of Si in the aluminum alloy material is 0.9 to 1.

[0012] The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2.4% to 2.8%.

[0013] The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.55%~0.7%.

[0014] In some embodiments, the tensile strength of the aluminum alloy material is 400MPa~420MPa.

[0015] In some embodiments, the bending angle of the aluminum alloy material is 70° to 85°.

[0016] A second aspect of this application provides a method for preparing the aluminum alloy material described in the first aspect of this application, comprising the following steps:

[0017] The raw materials for preparing the aluminum alloy material are prepared according to the chemical composition, and the raw materials are subjected to melting and casting treatment to prepare ingots;

[0018] The aluminum alloy material is prepared by homogenizing, extruding and aging the ingot.

[0019] In some embodiments, the step of homogenizing the ingot includes:

[0020] The ingot is subjected to a first-stage homogenization treatment at a temperature of 200℃~300℃, a second-stage homogenization treatment at a temperature of 540℃~560℃, and then cooled to 420℃~440℃ at a cooling rate of 300℃ / h~450℃ / h, and then cooled to room temperature at a cooling rate of 600℃ / h~700℃ / h.

[0021] In some embodiments, the extrusion process includes:

[0022] The homogenized intermediate is heated to 480℃~510℃ and extruded under the conditions of extrusion ratio of 20~35, extrusion speed of 2m / min~10m / min and extrusion temperature ≥535℃ to prepare aluminum alloy profiles; the aluminum alloy profiles are then quenched and cooled, wherein the quenching temperature is >520℃ and the quenching temperature is room temperature.

[0023] Alternatively, the quenching cooling method may be spray quenching or water quenching.

[0024] In some embodiments, the time-sensitive processing steps include:

[0025] The extruded intermediate was aged within 48 hours at an aging temperature of 170℃ to 210℃ for 1 to 14 hours.

[0026] In some embodiments, the melting and casting process is carried out at a temperature of 680°C to 710°C.

[0027] A third aspect of this application provides an aluminum alloy component comprising the aluminum alloy material described in any of the first aspects of this application.

[0028] Optionally, the aluminum alloy component is an automotive aluminum alloy component.

[0029] The aluminum alloy material provided in this application has at least the following advantages:

[0030] The aluminum alloy material provided in this application, through the regulation of its chemical composition and the control of the sum of the mass fractions of Mg, Si, and Cu at specific mass fractions, can form a greater number of strengthening phases in the aluminum alloy to ensure strength, while avoiding excessively large precipitates caused by excessive strengthening elements. This makes the aluminum alloy material less prone to cracking due to the fracture of coarse precipitates during bending. Furthermore, with the synergistic effect of the mass fractions of Mn, V, and Zr, it can form sufficient dispersed phases to hinder recrystallization, resulting in a uniform fibrous structure within the alloy; it can also reduce the precipitation of coarse phases at grain boundaries, which is beneficial for further improving the bending performance of the aluminum alloy material. Furthermore, the above-mentioned aluminum alloy material can meet the requirements of high strength and high energy absorption when the yield strength is 360 MPa to 380 MPa. Attached Figure Description

[0031] Figure 1 A process flow diagram of the aluminum alloy material preparation method provided in this application. Detailed Implementation

[0032] The following detailed description, in conjunction with specific embodiments, provides a more complete and clear account of the aluminum alloy material, its preparation method, and the aluminum alloy components described herein. This application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0033] In this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Unless otherwise stated or in case of conflict, the terms or phrases used herein have the following meanings:

[0036] In this application, the terms "multiple", "various", "multiple times", "multi-dimensional", etc., unless otherwise specified, refer to a quantity greater than or equal to 2. For example, "one or more" means one or more or more.

[0037] In this application, the terms "first aspect," "second aspect," "third aspect," and "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," and "fourth," etc., serve only a non-exhaustive enumeration purpose and should be understood not to constitute a closed limitation on quantity.

[0038] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0039] In this application, the terms "combinations thereof", "any combination thereof", and "any combination thereof" include all suitable combinations of any two or more of the listed items.

[0040] In this application, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0041] In this application, terms such as "preferred," "better," "more suitable," and "ideal" are used only to describe implementation methods or embodiments with better effects, and should be understood not to constitute a limitation on the scope of protection of this application.

[0042] In this application, terms such as "further," "even further," and "particularly" are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0043] In this application, the terms "optionally," "optionally," and "optional" refer to options that are optional, meaning they can be selected from either "with" or "without." If multiple "optional" options appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" option is independent.

[0044] In this application, numerical intervals (i.e., numerical ranges) are involved. Unless otherwise specified, the selected numerical distributions within the aforementioned numerical intervals are considered continuous and include the two endpoints (i.e., the minimum and maximum values) of the numerical range, as well as every value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints. In this document, this is equivalent to directly listing every integer. For example, if t is an integer selected from 1 to 10, it means that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Furthermore, when multiple ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0045] Unless otherwise specified, the temperature parameters in this application are permitted to be either constant-temperature treatment or variations within a certain temperature range. It should be understood that the constant-temperature treatment allows temperature fluctuations within the precision range of the instrument control, such as ±5℃, ±4℃, ±3℃, ±2℃, or ±1℃.

[0046] In this application, percentage content refers to mass percentage for solid-liquid mixtures and solid-phase-solid mixtures, and volume percentage for liquid-phase-liquid mixtures, unless otherwise specified.

[0047] In this application, unless otherwise specified, percentage concentrations refer to final concentrations. The final concentration refers to the percentage of the added component in the system after its addition.

[0048] To improve the strength of aluminum alloy materials used in automotive energy-absorbing aluminum alloy components, the current common practice is to increase the content of alloying elements, such as increasing the content of Si and Cu. While this method can improve the strength of the aluminum alloy material, it negatively impacts its bending performance. Other methods involve adding one or more elements such as La, Sr, Ce, Sc, Er, and B to control the microstructure, but this requires adding a significant amount of precious metals, resulting in higher costs. Therefore, aluminum alloy materials provided by traditional technologies cannot simultaneously possess good mechanical and bending properties, which is detrimental to their use as raw materials for energy-absorbing aluminum alloy components.

[0049] Based on this, in a first aspect, this application provides an aluminum alloy material comprising the following chemical composition by mass fraction: 0.8%~1.2% Si, 0.8%~1.3% Mg, 0.4%~0.8% Cu, 0.2%~0.7% Mn, 0.1%~0.3% Cr, 0.02%~0.05% Ti, 0~0.2% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al.

[0050] The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2% to 2.8%.

[0051] The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.4%~0.7%.

[0052] The aluminum alloy material provided in this application, through the regulation of its chemical composition and the control of the sum of the mass fractions of Mg, Si, and Cu at specific mass fractions, can form more strengthening phases in the aluminum alloy to ensure strength, while avoiding excessively large precipitate sizes caused by excessive strengthening elements. This makes the aluminum alloy material less prone to cracking caused by the fracture of coarse precipitates during bending. Furthermore, with the synergistic effect of the mass fractions of Mn, V, and Zr, it can form sufficient dispersed phases to hinder recrystallization, resulting in a uniform fibrous structure inside the alloy; it can also reduce the precipitation of coarse phases at grain boundaries, which is beneficial to further improving the bending performance of the aluminum alloy material. However, the above-mentioned aluminum alloy material fails to meet the requirements of high strength and high energy absorption when the yield strength is 360MPa~380MPa.

[0053] To avoid excessive elemental silicon in the aluminum alloy, which would affect bending performance, the mass fraction of Si is, for example, 0.8% to 1.2%. Understandably, the mass fraction of Si can be selected from any value between 0.8% and 1.2%. For example, the mass fraction of Si includes, but is not limited to, 0.8%, 0.9%, 0.95%, 1%, 1.05%, 1.08%, 1.1%, 1.15%, or 1.2%, or any two of the above values ​​as endpoints. Further, the mass fraction of Si is 1% to 1.1%. Even further, the mass fraction of Si is 1.05% to 1.1%.

[0054] When the mass fractions of Mg, Si, and Cu are within the above range, and the sum of the mass fractions of Mg, Si, and Cu is 2% to 2.8%, sufficient reinforcing phases can be formed in the alloy to ensure strength. At the same time, the excessive reinforcing elements will not cause the precipitates to be too large due to the inability to redissolve. This makes the aluminum alloy material less prone to cracking due to the fracture of coarse precipitates during bending.

[0055] Understandably, the mass fraction of Mg can be selected from any value between 0.8% and 1.3%. For example, the mass fraction of Mg includes, but is not limited to, 0.8%, 0.9%, 0.95%, 0.98%, 0.99%, 1%, 1.01%, 1.02%, 1.03%, 1.04%, 1.05%, 1.1%, 1.2%, or 1.3%, or any range formed by any two of the above values ​​as endpoints. Further, the mass fraction of Mg is 0.9% to 1.1%. Even further, the mass fraction of Mg is 0.95% to 1.05%.

[0056] The mass fraction of Cu can be selected from any value between 0.4% and 0.8%. For example, the mass fraction of Cu includes, but is not limited to, 0.4%, 0.42%, 0.43%, 0.45%, 0.48%, 0.5%, 0.52%, 0.55%, 0.58%, 0.6%, 0.62%, 0.65%, 0.7%, or 0.8%, or any range formed by any two of the above values ​​as endpoints. Further, the mass fraction of Cu is 0.4% to 0.65%. Even further, the mass fraction of Cu is 0.4% to 0.5%.

[0057] The sum of the mass fractions of Mg, Si, and Cu can be selected from any value between 2% and 2.8%. For example, the sum of the mass fractions of Mg, Si, and Cu includes, but is not limited to, 2.4%, 2.5%, 2.52%, 2.55%, 2.6%, 2.65%, 2.68%, 2.7%, or 2.8%, or any range formed by any two of the above values ​​as endpoints. Further, the sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2.4% to 2.8%. Even further, the sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2.4% to 2.6%.

[0058] The mass fractions of Mn, V, and Zr are within the aforementioned range, and the sum of Mn+3V+2Zr is 0.4%~0.7%. On one hand, weighting coefficients are set based on the efficiency of V and Zr in forming dispersed phases in the aluminum alloy to balance the contributions of different elements to the dispersed phase, ensuring sufficient dispersed phase formation in the aluminum alloy to hinder recrystallization, reduce the thickness of the coarse grain layer, and form a uniform fibrous structure. On the other hand, it can improve the morphology and size of the Fe phase, reduce the precipitation of coarse, blocky Fe-containing phases at grain boundaries, resulting in smaller sizes after homogenization and extrusion treatments, thus reducing the risk of fracture during bending. Furthermore, this application found that the specified sum of Mn+3V+2Zr in the aluminum alloy material can also avoid excessive quenching stress during extrusion treatment, reducing the risk of stress concentration and cracking during bending. For example, the sum of Mn + 3V + 2Zr includes, but is not limited to, 0.4%, 0.45%, 0.48%, 0.5%, 0.51%, 0.52%, 0.55%, 0.58%, 0.59%, 0.6%, 0.61%, 0.63%, 0.65%, 0.68%, 0.69%, or 0.7%, or any two of the above values ​​as endpoints. Further, the sum of the mass fraction of Mn in the aluminum alloy, three times the mass fraction of V in the aluminum alloy, and twice the mass fraction of Zr in the aluminum alloy is 0.55% to 0.7%.

[0059] Adding 0.1% to 0.3% Cr to aluminum alloys can form uniform and fine α-Al(Fe,Mn,Cr)Si dispersed phases that pin grain boundaries, hindering recrystallization and refining grains, thus helping to improve the bending properties of the material. For example, the mass fraction of Cr includes, but is not limited to, 0.15%, 0.18%, 0.19%, 0.2%, 0.21%, 0.22%, 0.23%, 0.25%, 0.28%, or 0.3%, or any two of the above values ​​as endpoints. Further, the mass fraction of Cr is 0.15% to 0.25%.

[0060] Adding 0.02% to 0.05% Ti to aluminum alloys can refine the as-cast grains by forming TiAl3, reducing casting defects, and improving the formability and uniformity of mechanical properties in subsequent processing. For example, the mass fraction of Ti includes, but is not limited to, 0.02%, 0.03%, 0.04%, or 0.05%, or any two of the above values ​​as endpoints.

[0061] Fe, as an unavoidable impurity element, can be controlled to a content of 0-0.2% to avoid the formation of coarse, brittle Al-Fe-Si intermetallic compound phases, thus reducing its detrimental effect on the alloy's plasticity. Simultaneously, adding certain amounts of Mn and Cr can also improve the morphology of the Fe-containing phase, thereby mitigating its harmful effects. For example, the mass fraction of Fe includes, but is not limited to, 0%, 0.05%, 0.08%, 0.1%, 0.11%, 0.12%, 0.15%, 0.18%, or 0.2%, or any two of the above values ​​as endpoints. Further, the mass fraction of Fe is 0.08% to 0.15%.

[0062] In some examples, the mass fraction ratio of Mg to Si in the aluminum alloy is 0.9 to 1.1. This Mg to Si mass fraction ratio in the aluminum alloy is conducive to the formation of the reinforcing phase Mg₂Si, avoiding performance degradation caused by excessive amounts of a single element (such as excessive Mg reducing corrosion resistance or excessive Si affecting plasticity), while maximizing the content of the reinforcing phase to improve material strength.

[0063] In some examples, the aluminum alloy material comprises the following chemical composition by mass fraction: 1%~1.1% Si, 0.9%~1.1% Mg, 0.4%~0.65% Cu, 0.3%~0.7% Mn, 0.15%~0.25% Cr, 0.02%~0.05% Ti, 0.08%~0.15% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al;

[0064] The ratio of the mass fraction of Mg to the mass fraction of Si in the aluminum alloy material is 0.9 to 1.

[0065] The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2.4% to 2.8%.

[0066] The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.55%~0.7%.

[0067] In some of these examples, the yield strength of the aluminum alloy material is 360 MPa to 380 MPa. The aluminum alloy material provided in this application has a higher yield strength, which meets the requirements for high strength and high energy absorption.

[0068] In some of these examples, the tensile strength of the aluminum alloy material is 400 MPa to 420 MPa.

[0069] In some of these examples, the bending angle of the aluminum alloy material is 70° to 85°.

[0070] In this application, the standard for yield strength and tensile strength testing is GB / T 228.1-2021 Metallic materials, tensile testing—Part 1: Test methods at room temperature. The standard for bending angle testing is VDA238-100: Plate Bending Test for Metallic Materials.

[0071] See Figure 1 A second aspect of this application provides a method for preparing the aluminum alloy material described in the first aspect of this application, comprising the following steps:

[0072] S10: Prepare the raw materials for the aluminum alloy material according to the chemical composition, and perform melting and casting treatment on the raw materials to prepare ingots.

[0073] S20: The aluminum alloy material is prepared by homogenizing, extruding and aging the ingot.

[0074] Understandably, in step S10, raw materials can be added according to their chemical composition. Examples of raw materials include, but are not limited to, pure aluminum ingots, magnesium ingots, copper wire, readily soluble silicon, manganese agent, chromium agent, Al-Si alloy, Al-Mn alloy, Al-Cr master alloy, aluminum-titanium-boron wire, and aluminum-titanium-carbon wire. In some examples, the mass percentage of recycled materials in the raw materials is ≤30%.

[0075] In some of these examples, the temperature of the melting and casting process in step S10 is 680°C to 710°C.

[0076] In some examples, in step S10, the casting process is a semi-continuous casting process, and the casting process includes a step of filtering the molten liquid. Further, the filtration includes sequentially filtering with 35-45 mesh and 46-50 mesh ceramic filter plates.

[0077] In some examples, the step of homogenizing the ingot includes:

[0078] The ingot is subjected to a first-stage homogenization treatment at a temperature of 200℃~300℃, a second-stage homogenization treatment at a temperature of 540℃~560℃, and then cooled to 420℃~440℃ at a cooling rate of 300℃ / h~450℃ / h, and then cooled to room temperature at a cooling rate of 600℃ / h~700℃ / h.

[0079] In this application, room temperature refers to 15℃~35℃.

[0080] For example, the temperature of the first-stage homogenization process includes, but is not limited to, 200℃, 205℃, 210℃, 220℃, 240℃, 260℃, 280℃, or 300℃, or any two of the above values ​​as endpoints. Furthermore, the duration of the first-stage homogenization process is 4h to 8h.

[0081] For example, the temperature of the second-stage homogenization process includes, but is not limited to, 545°C, 550°C, 555°C, or 560°C, or any two of the above values ​​as endpoints. Furthermore, the time for the second-stage homogenization process is 6 hours to 12 hours.

[0082] Cooling to 420℃~440℃ at a cooling rate of 300℃ / h~450℃ / h includes, but is not limited to, forced air cooling. The cooling rate in this process includes, but is not limited to, 350℃ / h, 365℃ / h, 370℃ / h, 372℃ / h, 375℃ / h, 390℃ / h, 400℃ / h, 420℃ / h, or 450℃ / h, or any two of the above values ​​as endpoints. The cooling temperature in this process includes, but is not limited to, 420℃, 425℃, 430℃, 435℃, or 440℃, or any two of the above values ​​as endpoints.

[0083] Cooling to room temperature at a cooling rate of 600℃ / h to 700℃ / h can be achieved by methods including, but not limited to, spraying. During this process, the cooling rate can include, but is not limited to, 630℃ / h, 650℃ / h, 652℃ / h, 655℃ / h, 660℃ / h, 680℃ / h, or 700℃ / h, or any two of the above values ​​as endpoints.

[0084] This application employs a two-stage homogenization process. The first-stage homogenization at low temperature facilitates the second-stage homogenization, forming uniformly distributed, fine-sized AlFeMn(Cr)Si dispersed phase particles at grain boundaries and within grains. These particles, along with the Al3Zr and Al3V dispersed phase particles formed during casting, inhibit recrystallization during extrusion, reducing the thickness of the coarse-grained layer in the aluminum alloy. This effectively and stably improves bending performance, strength, and corrosion resistance. The second-stage homogenization further allows for the complete dissolution of the Mg2Si phase, while simultaneously increasing the conversion rate from β-Fe to α-Fe, improving extrudability, and reducing the proportion of coarse, blocky Fe-containing phases, thereby enhancing the bending performance of the aluminum alloy. Furthermore, segmented cooling controls the size of the secondary precipitated Mg2Si phase during cooling to be less than 15 μm, thus minimizing the impact of coarse precipitates on relative strength and bending angle.

[0085] In some of these examples, the extrusion process includes the following steps:

[0086] The homogenized intermediate is heated to 480℃~510℃ and extruded under the conditions of extrusion ratio of 20~35, extrusion speed of 2m / min~10m / min and extrusion temperature ≥535℃ to prepare aluminum alloy profiles; the aluminum alloy profiles are quenched and cooled, wherein the quenching temperature is >520℃ and the quenching temperature is room temperature.

[0087] To ensure uniform heating of the homogenized intermediate, in some examples, before heating the homogenized intermediate to 480°C~510°C, the homogenized intermediate is cut. Understandably, if the length of the homogenized intermediate is too long, it can be cut to a length of 500mm~700mm. However, if the length of the homogenized intermediate is short, less than 700mm, then cutting is unnecessary.

[0088] In some examples, the apparatus for heating the homogenized intermediate to 480°C~510°C is an industrial frequency heating furnace. The heating time for this process is 3 min~5 min.

[0089] In this application, the extrusion ratio refers to the ratio of the cross-sectional area of ​​the intermediate body before extrusion to the cross-sectional area of ​​the aluminum alloy profile after extrusion. Further, the extrusion temperature is 535℃~545℃. The quenching temperature is >520℃ and <535℃. Even further, the quenching temperature is 528℃. Optionally, the quenching cooling method is spray quenching or water quenching. The exit quenching temperature is room temperature. As a further example, the exit quenching temperature is 25℃~30℃.

[0090] In some of these examples, the timeliness processing steps include:

[0091] The extruded intermediate was aged within 48 hours at an aging temperature of 170℃ to 210℃ for 1 to 14 hours.

[0092] For example, the aging temperature includes, but is not limited to, 180°C, 190°C, 195°C, 200°C or 210°C, or any two of the above point values ​​as endpoints within a range.

[0093] In one specific example, the method for preparing aluminum alloy material includes the following steps:

[0094] (1) Preparation of raw materials: Prepare the raw materials for the aluminum alloy material according to the chemical composition. Use a semi-continuous casting process to melt and cast the raw materials at a temperature of 680℃~710℃. Then filter them sequentially with ceramic filter plates of 35 mesh~45 mesh and 46 mesh~50 mesh to prepare ingots.

[0095] (2) Homogenization treatment: The ingot is subjected to a first-stage homogenization treatment at a temperature of 200℃~300℃ for 4h~8h, and a second-stage homogenization treatment at 540℃~560℃ for 6h~12h. After that, it is transferred and cooled within a time of <10min. Then, it is cooled to 420℃~440℃ by strong air at a cooling rate of 300℃ / h~450℃ / h, and then cooled to room temperature by spray at a cooling rate of 600℃ / h~700℃ / h.

[0096] (3) Extrusion treatment: The homogenized intermediate is heated to 480℃~510℃ in an industrial frequency heating furnace for 3min~5min; then extruded under the conditions of extrusion ratio of 20~35, extrusion speed of 2m / min~10m / min and extrusion temperature ≥535℃ to prepare aluminum alloy profiles; the aluminum alloy profiles are quenched and cooled, wherein the quenching temperature is >520℃ and the quenching temperature is room temperature, and the quenching and cooling method is spraying or water quenching.

[0097] (4) Aging treatment: The extruded intermediate is aged within 48 hours at an aging temperature of 170℃~210℃ for 1h~14h to prepare aluminum alloy materials.

[0098] In the preparation method provided in this application, by optimizing the process parameters of homogenization treatment, extrusion treatment and aging treatment, and controlling the temperature and cooling rate, the size of the precipitated phase can be further controlled, avoiding the influence of coarse second phase on bending and crushing performance, and improving the stability of production.

[0099] A third aspect of this application provides an aluminum alloy component comprising the aluminum alloy material described in any of the first aspects of this application.

[0100] Optionally, the aluminum alloy component is an automotive aluminum alloy component.

[0101] For example, aluminum alloy components for automobiles include, but are not limited to, anti-collision beams, energy-absorbing boxes, door sill beams, and battery pack housings for new energy vehicles.

[0102] The following detailed embodiments illustrate this application in more detail. It should also be understood that the following embodiments are for further explanation only and should not be construed as limiting the scope of protection of this application. Any non-essential improvements and adjustments made by those skilled in the art based on the above description of this application fall within the scope of protection of this application. The specific process parameters, etc., in the following embodiments are merely examples within a suitable range; that is, those skilled in the art can make appropriate selections within the range based on the description herein, and are not necessarily limited to the specific values ​​in the embodiments below.

[0103] Examples 1 to 5

[0104] The preparation methods of the aluminum alloy materials provided in Examples 1 to 5 include the following steps:

[0105] (1) Preparation of raw materials: Prepare the raw materials for aluminum alloy materials according to the chemical composition in Table 1. The raw materials are melted and cast at a temperature of 680℃~710℃ using a semi-continuous casting process. Then, the materials are filtered in two stages using 40-mesh and 50-mesh ceramic filter plates. The casting diameter is 178mm and the casting length is 6500mm to prepare the ingot.

[0106] (2) Homogenization treatment: The ingot is subjected to a two-stage homogenization process, which involves first-stage homogenization treatment at 205℃ for 6 hours and second-stage homogenization treatment at 550℃ for 10 hours. After that, it is transferred and cooled within 6 minutes. The temperature after the transfer is 523℃. Then, it is cooled to 430℃ by strong air at a cooling rate of 372℃ / h and then cooled to room temperature by spray at a cooling rate of 652℃ / h.

[0107] (3) Extrusion treatment: The homogenized intermediate is cut into short rods with a length of 600 mm. The short rods are heated to 490℃~510℃ in an industrial frequency heating furnace for 4 min. Then, they are extruded under the conditions of extrusion ratio of 22.6, extrusion speed of 4.7 m / min and extrusion temperature of 535℃ (die exit temperature of 535℃) to prepare aluminum alloy profiles. The aluminum alloy profiles are quenched and cooled, with an inlet quenching temperature of 528℃ and an outlet quenching temperature of 28℃. The quenching and cooling method is spraying.

[0108] (4) Aging treatment: After the extrusion treatment, the intermediate is left to stand for 2h~8h and then aged. The aging temperature is 195℃ and the aging time is 2h to prepare aluminum alloy material.

[0109] Table 1 Chemical composition of aluminum alloy materials in Examples 1-5

[0110]

[0111] Comparative Examples 1 to 2

[0112] The preparation methods of the aluminum alloy materials in Comparative Examples 1 and 2 are basically the same as those in Examples 1 and 3. The main difference lies in the different chemical compositions of the aluminum alloy materials in Comparative Examples 1 and 2. The chemical compositions of the aluminum alloy materials in Comparative Examples 1 and 2 are shown in Table 2.

[0113] Table 2 Chemical composition of aluminum alloy materials in Comparative Examples 1-3

[0114]

[0115] Comparative Example 3

[0116] The preparation method of the aluminum alloy material in Comparative Example 3 is basically the same as that in Examples 1 to 5. The main difference is that the chemical composition of the aluminum alloy material in Comparative Example 3 is different, and steps (2) and (4) of Comparative Example 3 are different from those in Examples 1 to 5. The chemical composition of the aluminum alloy material in Comparative Example 3 is shown in Table 2.

[0117] Step (2) of Comparative Example 3 is as follows: Homogenization treatment: The ingot is homogenized at 550°C for 10 hours using a single-stage homogenization process. Then, it is transferred and cooled within 6 minutes. The temperature after transfer is 523°C. Then, it is cooled to 430°C by strong wind at a cooling rate of 372°C / h. Finally, it is cooled to room temperature by spraying at a cooling rate of 652°C / h.

[0118] Step (4) of Comparative Example 3 is as follows: Aging treatment: After the extrusion treatment, the intermediate is left to stand for 2h~8h and then aged. The aging temperature is 175℃ and the aging time is 8h to prepare aluminum alloy material.

[0119] The aluminum alloy materials used in the above embodiments and comparative examples were tested for tensile strength, yield strength, elongation, and bending angle. The corresponding test conditions are as follows:

[0120] (1) Tensile strength: measured according to the standard GB / T 228.1-2021 Metallic materials tensile test part 1: test method at room temperature.

[0121] (2) Yield strength: measured according to the standard GB / T 228.1-2021 Metallic materials tensile testing Part 1: room temperature test method.

[0122] (3) Elongation: The elongation was measured according to the standard GB / T 228.1-2021 Metallic Materials Tensile Testing Part 1: Room Temperature Test Method.

[0123] (4) Bending angle: measured according to the standard of "VDA238-100: Plate Bending Test for Metallic Materials".

[0124] The test data of the aluminum alloy materials in the above embodiments and comparative examples are shown in Table 3.

[0125] Table 3 Test data of aluminum alloy materials in the examples and comparative examples

[0126]

[0127] As can be seen from Table 3, compared with the comparative example, the embodiments of this application have good mechanical properties and excellent bending performance.

[0128] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0129] The embodiments described above are merely illustrative of several implementation methods of this application, intended to facilitate a detailed understanding of the technical solutions of this application, but should not be construed as limiting the scope of protection of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. It should be understood that technical solutions obtained by those skilled in the art based on the technical solutions provided in this application through logical analysis, reasoning, or limited experimentation are all within the scope of protection of the appended claims. Therefore, the scope of protection of this patent application should be determined by the content of the appended claims, and the specification can be used to interpret the content of the claims.

Claims

1. An aluminum alloy material, characterized in that, The aluminum alloy material comprises the following chemical components by mass fraction: 0.8%~1.2% Si, 0.8%~1.3% Mg, 0.4%~0.8% Cu, 0.2%~0.7% Mn, 0.1%~0.3% Cr, 0.02%~0.05% Ti, 0~0.2% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al; The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2% to 2.8%. The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.4%~0.7%; The yield strength of the aluminum alloy material is 360MPa~380MPa.

2. The aluminum alloy material according to claim 1, characterized in that, The ratio of the mass fraction of Mg to the mass fraction of Si in the aluminum alloy material is 0.9 to 1.

1.

3. The aluminum alloy material according to claim 1 or 2, characterized in that, The aluminum alloy material comprises the following chemical composition by mass fraction: 1%~1.1% Si, 0.9%~1.1% Mg, 0.4%~0.65% Cu, 0.3%~0.7% Mn, 0.15%~0.25% Cr, 0.02%~0.05% Ti, 0.08%~0.15% Fe, 0~0.05% V, 0~0.1% Zr, and 95.3%~97.68% Al; The ratio of the mass fraction of Mg to the mass fraction of Si in the aluminum alloy material is 0.9 to 1. The sum of the mass fractions of Mg, Si, and Cu in the aluminum alloy material is 2.4% to 2.8%. The sum of the mass fraction of Mn in the aluminum alloy material, three times the mass fraction of V in the aluminum alloy material, and twice the mass fraction of Zr in the aluminum alloy material is 0.55%~0.7%.

4. The aluminum alloy material according to claim 1 or 2, characterized in that, The aluminum alloy material has one or more of the following characteristics: (1) The tensile strength of the aluminum alloy material is 400MPa~420MPa; (2) The bending angle of the aluminum alloy material is 70°~85°.

5. A method for preparing the aluminum alloy material according to any one of claims 1 to 4, characterized in that, Includes the following steps: The raw materials for preparing the aluminum alloy material are prepared according to the chemical composition, and the raw materials are subjected to melting and casting treatment to prepare ingots; The aluminum alloy material is prepared by homogenizing, extruding and aging the ingot.

6. The method for preparing aluminum alloy material according to claim 5, characterized in that, The steps for homogenizing the ingot include: The ingot is subjected to a first-stage homogenization treatment at a temperature of 200℃~300℃, a second-stage homogenization treatment at a temperature of 540℃~560℃, and then cooled to 420℃~440℃ at a cooling rate of 300℃ / h~450℃ / h, and then cooled to room temperature at a cooling rate of 600℃ / h~700℃ / h.

7. The method for preparing aluminum alloy material according to claim 5 or 6, characterized in that, The extrusion process includes the following steps: The homogenized intermediate is heated to 480℃~510℃ and extruded under the conditions of extrusion ratio of 20~35, extrusion speed of 2m / min~10m / min and extrusion temperature ≥535℃ to prepare aluminum alloy profiles; the aluminum alloy profiles are then quenched and cooled, wherein the quenching temperature is >520℃ and the quenching temperature is room temperature. Alternatively, the quenching cooling method may be spray quenching or water quenching.

8. The method for preparing aluminum alloy material according to claim 5 or 6, characterized in that, The steps for timeliness processing include: The extruded intermediate was aged within 48 hours at an aging temperature of 170℃ to 210℃ for 1 to 14 hours.

9. The method for preparing aluminum alloy material according to claim 5 or 6, characterized in that, The temperature for the melting and casting process is 680℃~710℃.

10. An aluminum alloy component, characterized in that, Includes the aluminum alloy material as described in any one of claims 1 to 4; Optionally, the aluminum alloy component is an automotive aluminum alloy component.

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