High-strength aluminum alloy material and preparation method and application thereof

Abstract

The invention belongs to aluminum alloy materials, and particularly relates to a high-strength aluminum alloy material and a preparation method and application thereof. The high-strength aluminum alloy material is prepared from the following components in percentage by mass: 1.00 percent to 1.20 percent of Si, 1.10 percent to 1.30 percent of Mg, 0.90 percent to 1.20 percent of Cu, 0.50 percent to 0.75 percent of Mn, 0.10 percent to 0.30 percent of Cr and 0.05 percent of Zr. The components of the high-strength aluminum alloy material can still be prepared at a higher extrusion speed (such as 10m / min), and the obtained aluminum alloy material has the tensile strength of more than or equal to 410MPa, the yield strength of more than or equal to 390MPa, the ductility of more than or equal to 14.5% and low quenching sensitivity.

Description

Technical Field

[0001] This invention pertains to aluminum alloy materials, specifically relating to a high-strength aluminum alloy material, its preparation method, and its applications. Background Technology

[0002] Commercial vehicle (truck / bus) structural components place stringent comprehensive requirements on material performance: they must simultaneously meet the high strength requirement of tensile strength ≥400MPa, good weldability, and resistance to stress corrosion to ensure structural safety and service life. Currently, the industry mainly uses two types of aluminum alloys: one is 7004 aluminum alloy, which has a strength of up to 450MPa, but suffers from low extrusion speed (≤3m / min) leading to low production efficiency, high stress corrosion sensitivity, and poor weldability; the other is traditional 6-series aluminum alloys (such as 6061 and 6082), which, although having a fast extrusion speed (up to 10m / min), low stress corrosion sensitivity, and excellent weldability, have a strength of only about 350MPa, failing to meet the requirements of high-strength structural components. Neither of these can simultaneously match the comprehensive performance indicators of commercial vehicle structural components; therefore, there is an urgent need to develop a high-strength 6-series aluminum alloy hollow profile that can replace 7004 aluminum alloy.

[0003] The core technological bottlenecks hindering the strength of traditional 6-series aluminum alloys lie primarily in two aspects: First, the limitation of Cu content leads to a strength bottleneck. Most existing patents limit the Cu content to 0.1%–0.5% to avoid extrusion cracking and reduced corrosion resistance, but underestimate the crucial role of Cu in age-hardening—low Cu content makes it difficult to form sufficient strengthening phases (such as Cu2Mg8Si6Al5 and GP zones), resulting in material strength generally below 380 MPa. Second, an imbalanced Mg / Si ratio causes performance imbalance. Traditional 6-series aluminum alloys use Mg2Si as the main strengthening phase, typically designed with an atomic ratio of Mg / Si = 1.73 to ensure complete Mg2Si formation. However, in practical applications, the Mg / Si ratio is poorly controlled: when Mg is excessive, corrosion resistance improves, but insufficient precipitation of the Mg2Si strengthening phase leads to a decrease in strength; when Si is excessive, while the free Si phase can slightly increase strength, it drastically reduces material elongation and anodizing effect, ultimately leading to performance imbalance.

[0004] Existing technologies for improving 6-series aluminum alloys have failed to effectively overcome the aforementioned bottlenecks: either excessive restrictions on Cu content sacrifice strength, or improper control of the Mg / Si ratio leads to a trade-off in performance. Therefore, how to improve the strength of 6-series aluminum alloys to the 400MPa level through optimized composition design while ensuring extrusion speed, weldability, and corrosion resistance has become a key issue in meeting the material requirements for commercial vehicle structural components. Developing a 6-series aluminum alloy hollow profile that combines high strength (≥400MPa) and high extrusion speed (≥5m / min) is of great significance for replacing 7004 aluminum alloy and promoting lightweighting and performance upgrades in commercial vehicles. Summary of the Invention

[0005] Based on the composition of 6-series aluminum alloys, this invention increases the copper (Cu) content while controlling the magnesium and silicon content, and can still obtain high-strength aluminum alloy materials with tensile strength ≥420MPa, yield strength ≥400MPa, and elongation ≥16% at high extrusion speeds (10m / min).

[0006] To achieve the above objectives, the present invention can adopt the following technical solutions: This invention provides a high-strength aluminum alloy material comprising the following components by mass fraction: Si 1.00%–1.20%, Mg 1.10%–1.30%, Cu 0.90%–1.20%, Mn 0.50%–0.75%, Cr 0.10%–0.30%, Zr ≤0.05%, and unavoidable impurities and balance Al.

[0007] Preferably, in the above-mentioned high-strength aluminum alloy material, the atomic ratio of Mg to Si is (0.85-1.15):1.

[0008] Preferably, the high-strength aluminum alloy material mentioned above is selected from any one of the following: (a) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.20%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (b) The composition by mass fraction includes the following components: Si 1.20%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (c) The composition includes the following components by mass fraction: Si 1.10%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (d) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.10%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al.

[0009] Preferably, the high-strength aluminum alloy material is a hollow profile.

[0010] Preferably, the cavity profile meets one or more of the following conditions: (a2) the wall thickness of the cavity profile is ≥1.5mm; (b2) the cross-sectional area of ​​the cavity profile is ≤32400mm². 2 (c2) The cavity profile is a single-layer cavity structure; (d2) The cross-section of the cavity profile has ≥80% similarity symmetry.

[0011] Another aspect of the present invention provides a method for preparing the above-mentioned high-strength aluminum alloy material. The preparation method includes: sequentially melting the raw materials, continuously casting, homogenizing, extruding, quenching, and aging to obtain the high-strength aluminum alloy material.

[0012] Preferably, in the above preparation method, the extrusion speed is ≤10m / min; and / or the quenching and transfer time after extrusion is ≤15s.

[0013] Preferably, the above preparation method satisfies one or more of the following conditions: (a3) ​​the melting temperature is 740℃~760℃; (b3) the homogenization treatment includes: a temperature of 550℃~570℃, a holding time of 7h~12h, and air cooling; (c3) the extrusion temperature is 500℃~550℃; (d3) the quenching method is online quenching; (e3) the aging treatment includes: a temperature of 170℃~180℃, a holding time of 7h~10h, and air cooling after exiting the furnace.

[0014] Preferably, in the above preparation method, the cooling methods for cooling after homogenization, cooling after quenching, and cooling after aging are independently selected as water cooling, mist cooling, or air cooling, respectively.

[0015] In another aspect, the present invention provides an automotive component or battery box made of the aforementioned high-strength aluminum alloy material.

[0016] The beneficial effects of this invention include: the high-strength aluminum alloy material composition provided by this invention can still be used to prepare high-strength aluminum alloy materials at a relatively high extrusion speed (e.g., 10m / min). The obtained aluminum alloy material has a tensile strength ≥410MPa, a yield strength ≥390MPa, an elongation ≥14.5%, and low quenching sensitivity. It can replace the currently used 7004 aluminum alloy and overcomes the problem of insufficient strength of traditional 6-series aluminum alloys. Attached Figure Description

[0017] Figure 1 The coarse-grained layer of the sample prepared in Example 1; Figure 2 The coarse-grained layer of the sample prepared in Comparative Example 4; Figure 3 The coarse-grained layer of the sample prepared for Comparative Example 5. Detailed Implementation

[0018] The embodiments described are provided to better illustrate the present invention, but are not intended to limit the scope of the invention to the embodiments described. Therefore, non-essential improvements and adjustments made to the embodiments by those skilled in the art based on the above description are still within the scope of protection of the present invention.

[0019] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. Singular expressions include plural expressions unless they have a distinct meaning in the context. As used herein, it should be understood that terms such as “comprising,” “having,” “including,” are intended to indicate the presence of features, numbers, operations, components, parts, elements, materials, or combinations thereof. The terminology of the invention is disclosed in the specification and is not intended to exclude the possibility that one or more other features, numbers, operations, components, parts, elements, materials, or combinations thereof may be present or added. As used herein, “ / ” may be interpreted as “and” or “or,” depending on the context.

[0020] In a first aspect, embodiments of the present invention provide a high-strength aluminum alloy material comprising, by mass fraction, the following components: Si 1.00%–1.20%, Mg 1.10%–1.30%, Cu 0.90%–1.20%, Mn 0.50%–0.75%, Cr 0.10%–0.30%, Zr ≤0.05%, and unavoidable impurities and the balance Al.

[0021] It should be noted that this invention, based on the composition of 6-series aluminum alloys, increases the copper (Cu) content and controls the magnesium and silicon contents to obtain a high-strength aluminum alloy material with a tensile strength ≥420MPa, a yield strength ≥400MPa, and an elongation ≥16%. It also exhibits low quenching sensitivity and can replace the currently used 7004 aluminum alloy, while overcoming the problem of insufficient strength in traditional 6-series aluminum alloys. Specifically, the Cu content in this invention is controlled between 0.90% and 1.20%, which promotes the precipitation of high-density GP zones and θ″ phases, enhancing the age-hardening effect. Through the dual strengthening mechanism of Cu and Mg2Si, multiple nanoscale strengthening phases are formed during aging, synergistically enhancing the matrix strength. Simultaneously, good extrusion resistance and corrosion resistance are maintained by controlling the Mg and Si contents. Furthermore, Mn can increase the recrystallization temperature, and Cr and Ti can refine the grains; strictly controlling Fe ≤0.15% reduces the brittle β-AlFeSi phase and improves corrosion resistance.

[0022] In some specific examples, the atomic ratio of Mg to Si in the above-mentioned high-strength aluminum alloy materials is (0.85-1.15):1.

[0023] It should be noted that the present invention can further control the atomic ratio of Mg to Si to be (0.85-1.15):1, such as 0.9:1, 1:1, or 1.12:1. Specifically, an atomic ratio of Mg to Si of (0.85-1.15):1 can ensure that the Mg2Si phase is fully precipitated, avoiding the negative impact of free Si on plasticity and extrudability.

[0024] In some specific examples, the above-mentioned high-strength aluminum alloy material is selected from any of the following: (a) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.20%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (b) The composition by mass fraction includes the following components: Si 1.20%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (c) The composition includes the following components by mass fraction: Si 1.10%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (d) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.10%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al.

[0025] It should be noted that the high-strength aluminum alloy materials listed above (a) to (d) have a tensile strength ≥420 MPa, a yield strength ≥400 MPa, and an elongation ≥16%.

[0026] In some specific examples, the aforementioned high-strength aluminum alloy material is a hollow profile.

[0027] It should be noted that the profile shape of the aluminum alloy material in this invention is well known in the art, and can preferably be a hollow profile, that is, the composition of the aluminum alloy material in this invention is more suitable for hollow profiles.

[0028] In some specific examples, the above-mentioned cavity profiles satisfy one or more of the following conditions: (a2) The wall thickness of the cavity profile is ≥1.5mm; specifically, the cavity profile prepared based on the aluminum alloy material composition of the present invention still has excellent mechanical properties when the wall thickness is 1.5mm, and the preferred wall thickness is 1.5mm to 3mm. (b2) The cross-sectional area of ​​the cavity profile is ≤32400mm² 2 Specifically, the hollow profile in this invention has a medium to large cross-section, and its maximum external dimension (width or height direction, or diagonal direction) is limited by this diameter; the hollow profile prepared based on the aluminum alloy material composition of this invention has a cross-sectional area ≤32400mm². 2 At the same time, they all exhibit excellent mechanical properties; (c2) The cavity profile is a single-layer cavity structure; (d2) The cross-section of the cavity profile has ≥80% similarity symmetry.

[0029] Secondly, embodiments of the present invention provide a method for preparing the above-mentioned high-strength aluminum alloy material. The preparation method includes: sequentially melting the raw materials, continuously casting, homogenizing, extruding, quenching, and aging to obtain the high-strength aluminum alloy material.

[0030] In some specific examples, the extrusion speed in the above preparation method is ≤10m / min.

[0031] It should be noted that the aluminum alloy material components in this invention can still produce aluminum alloy materials with excellent mechanical properties at high extrusion speeds (≤10m / min), with the maximum extrusion speed reaching 10m / min. However, if the extrusion speed is too high, continuous or discontinuous, tear-like longitudinal lines will appear on the profile surface. In severe cases, cracks will be very obvious, leading to direct product scrap. Furthermore, poor surface quality, out-of-tolerance dimensional accuracy, and poor mechanical properties will also result.

[0032] In some specific examples, in the above preparation method, the quenching and transfer time after extrusion is ≤15s.

[0033] It should be noted that the quenching transfer time after extrusion refers to the interval between the end of extrusion and the start of quenching. The aluminum alloy material in this invention has a relatively weak quenching sensitivity. The mechanical properties of the aluminum alloy material prepared by quenching within 90s are similar to those of the aluminum alloy material prepared by quenching immediately after extrusion. In particular, the mechanical properties of the aluminum alloy material prepared by quenching within 15s are even less different from those of the aluminum alloy material prepared by quenching immediately after extrusion.

[0034] In some specific examples, the above preparation method satisfies one or more of the following conditions: (a3) The melting temperature is 740℃~760℃, such as 745℃, 750℃ or 755℃, etc.; (b3) Homogenization treatment includes: a temperature of 550℃~570℃, a holding time of 7h~12h (such as 8h, 9h, 10h or 11h, etc.), and air cooling; (c3) The extrusion temperature is 500℃~550℃, such as 510℃, 520℃, 530℃ or 540℃, etc.; (d3) The quenching method is current quenching; (e3) Aging treatment includes: temperature of 170℃~180℃ (such as 173℃, 175℃ or 177℃, etc.), holding time of 7h~10h (8h or 9h, etc.), and air cooling after taking it out of the furnace.

[0035] It should be noted that other preparation parameters of the aluminum alloy material preparation method in this invention can be as listed above.

[0036] In some specific examples, in the above preparation method, the cooling methods for cooling after homogenization, cooling after quenching, and cooling after aging are independently selected as water cooling, mist cooling, or air cooling, respectively.

[0037] It should be noted that the cooling method in this invention is well known in the art, such as water cooling, mist cooling, or air cooling.

[0038] Thirdly, embodiments of the present invention provide an automotive component or battery box made of the aforementioned high-strength aluminum alloy material.

[0039] It should be noted that the aluminum alloy material in this invention is suitable for thin-walled and medium-to-large cross-section hollow profiles, such as those used in automotive structural components or battery boxes. It is particularly suitable for structural profiles in commercial vehicles (such as trucks and buses).

[0040] To better understand the present invention, specific examples are provided below to further illustrate the content of the present invention, but the content of the present invention is not limited to the examples below.

[0041] In the following examples and comparative examples, the parameters of the semi-continuous casting process are shown in Table 1 below.

[0042] Table 1 Semi-continuous casting process Preparation Examples Example 1 (1) Prepare the raw materials according to the components shown in Table 2; Table 2 Raw material composition of Example 1 (2) Melt the prepared raw materials at 750°C, and stir them thoroughly during the melting process to ensure that the components are uniform; (3) Ingots are prepared using a semi-continuous casting process; (4) After the ingot is prepared, it is homogenized at 570℃, kept at the temperature for 10 hours, and then cooled naturally at room temperature (air cooling). (5) Then the homogenized ingot is extruded. During the extrusion process, the ingot is heated by gradient and isothermal to ensure the consistency of the outlet temperature. The outlet temperature is controlled at 530℃ and the extrusion speed is 10m / min. (6) Immediately after extrusion, perform online quenching (water cooling); (7) After quenching, perform aging treatment (180℃, heat preservation for 8 hours, and natural cooling at room temperature (air cooling)) to obtain the cavity profile.

[0043] Example 2 Examples 2 to 5 are largely the same as Example 1, except that the proportions of raw material components are different, while the rest are the same as Example 1; the raw material components in Examples 2 to 5 are shown in Table 3 below.

[0044] Table 3 Raw material components in Examples 2 to 5 Examples 6 to 7 Examples 6 and 7 are largely the same as Example 1, except that the proportions of raw material components are different, while the rest are the same as in Example 1; the raw material components in Examples 6 and 7 are shown in Table 4 below.

[0045] Table 4 Raw material components in Examples 6 and 7 Examples 8 to 9 Examples 8 to 9 are largely the same as Example 1, except that the proportions of raw material components are different, while the rest are the same as in Example 1; the raw material components in Examples 8 to 9 are shown in Table 5 below.

[0046] Table 5 Raw material components in Examples 8 to 9 Examples 10 to 13 Examples 10 to 13 are largely the same as Example 1, except that the quenching transfer time is different (Example 1 is online quenching, and the transfer time is counted as 0), and the rest is the same as Example 1; wherein, the quenching transfer time of Examples 10, 11, 12 and 13 is 15s, 30s, 60s or 90s respectively.

[0047] Comparative Examples 1 to 3 Comparative Examples 1 to 3 are largely the same as Example 1, except that the proportions of the raw material components are different, while the rest are the same as Example 1; the raw material components in Comparative Examples 1 to 3 are shown in Table 6 below.

[0048] Table 6. Raw material components in Comparative Examples 1 to 3 Comparative Examples 4 to 5 Comparative Examples 4 and 5 are largely the same as Example 1, except that the proportions of the raw material components are different, while the rest are the same as in Example 1; the raw material components in Comparative Examples 4 and 5 are shown in Table 7 below.

[0049] Table 7. Raw material composition of Comparative Examples 4 to 5 Comparative Example 6 Hollow profiles were prepared by using the raw material composition of 6061 aluminum alloy according to the preparation method of Example 1, wherein the extrusion speed was 5 m / min and other preparation steps were the same as in Example 1; wherein the raw material composition ratio of 6061 aluminum alloy is shown in Table 8 below.

[0050] Table 8. Raw material composition ratio of 6061 aluminum alloy Comparative Example 7 Hollow profiles were prepared from 6082 aluminum alloy using the same raw material composition as in Example 1, with an extrusion speed of 5 m / min and other preparation steps identical to those in Example 1. The proportions of the 6082 aluminum alloy raw material composition are shown in Table 9 below.

[0051] Table 9. Raw material composition ratio of 6082 aluminum alloy Comparative Example 8 A hollow profile was prepared by using the raw material composition of 6061 aluminum alloy according to the preparation method of Example 1 (extrusion speed of 10m / min). The preparation steps were the same as in Example 1. The prepared hollow profile cracked and did not meet the requirements.

[0052] Comparative Example 9 A hollow profile was prepared by using the raw material composition of 6082 aluminum alloy according to the preparation method of Example 1 (extrusion speed of 10m / min). The preparation steps were the same as in Example 1. The prepared hollow profile cracked and did not meet the requirements.

[0053] Characterization test The coarse-grained layer thickness of the cavity profiles prepared in Example 1, Comparative Example 4, and Comparative Example 5 were tested respectively, and the results are as follows: Figure 1 , Figure 2 and Figure 3 As shown, the results indicate that the coarse grain layer thickness of the cavity profile prepared in Example 1 is 225 μm, the coarse grain layer thickness of the cavity profile prepared in Comparative Example 4 is 1322 μm, and the coarse grain layer thickness of the cavity profile prepared in Comparative Example 5 is >1800 μm.

[0054] Comparing Comparative Example 4 and Comparative Example 5, it can be seen that Comparative Example 4 increased Zr (content was 0.05%) compared to Comparative Example 5, and the coarse grain layer thickness of the prepared cavity profile was significantly reduced, indicating that Zr can play a role in reducing the coarse grain layer depth. In addition, comparing Example 1 and Comparative Example 4, it can be seen that Example 1 increased the Cr content to 0.24% compared to Comparative Example 1, and its coarse grain layer depth was significantly reduced, indicating that increasing the Cr content can further reduce the coarse grain layer depth.

[0055] Performance testing Three parallel samples were taken from the hollow profiles prepared in the examples and comparative examples respectively (the samples prepared in comparative examples 8 and 9 were cracked and were not further tested for mechanical properties). Then, tensile tests were carried out using an electronic universal testing machine according to the standard GB / T 228.1-2021 to test the yield strength, tensile strength and elongation. The average value of the three parallel samples was calculated and the calculation results are shown in Table 10 below.

[0056] Table 10 Mechanical properties of hollow profile samples prepared in the examples / comparative examples As shown in Table 10 above, the yield strength, tensile strength, and elongation of the aluminum alloy materials prepared in Examples 1 to 13 are all higher than those in Comparative Examples 1 to 6; among which: Comparing Examples 1 to 9 with Comparative Examples 1 and 2, it can be seen that the mass percentages of Comparative Examples 1 and 2 are not within the scope of this invention (Si 1.00% to 1.20%, Mg 1.10% to 1.30%). Among them, the yield strength, tensile strength and elongation of Comparative Example 1 are significantly lower than those of Examples 1 to 9. Comparing Example 1 and Comparative Example 3, it can be seen that the copper content of Comparative Example 3 is greater than 1.20%. The results show that the copper content is too high, and the yield strength, tensile strength and elongation are significantly lower than those of Examples 1 to 9. Comparing Examples 1, 4, and 5, it can be seen that Comparative Example 4 increased Zr content (0.05%) compared to Comparative Example 5, resulting in a significant increase in mechanical properties. This indicates that Zr enhances the mechanical properties of aluminum alloys, consistent with the trend of coarse grain layer thickness. Furthermore, comparing Example 1 with Comparative Example 4, it can be seen that Example 1 increased Cr content to 0.24%, resulting in a significant increase in mechanical properties. This indicates that increasing Cr content can further enhance the mechanical properties of aluminum alloys. Comparing Example 1, Comparative Example 6, and Comparative Example 7, it can be seen that Comparative Example 4 and Comparative Example 5 used the components of aluminum alloys 6061 and 6082, respectively. After reducing the extrusion speed (this extrusion speed is applicable to aluminum alloys 6061 and 6082), the yield strength, tensile strength, and elongation of the aluminum alloy 6061 and 6082 materials prepared according to the preparation method of the present invention in other steps were significantly lower than those in Example 1. In addition, Comparative Example 8 significantly increased the extrusion speed based on Comparative Example 6, and as in Example 1, cracking occurred after increasing the extrusion speed. Comparative Example 9 also significantly increased the extrusion speed based on Comparative Example 7, and as in Example 1, cracking also occurred after increasing the extrusion speed. Comparing Example 1 with Examples 10 to 13 reveals that Examples 10 to 13 increased the quenching transfer time. The results show that with the increase in quenching transfer time, the yield strength, tensile strength, and elongation of the prepared aluminum alloy material did not change significantly, indicating low quenching sensitivity. Based on this, it can be concluded that increasing the Cr content in this invention not only does not increase quenching sensitivity but also refines the grains, reduces the depth of coarse grains on the surface, and improves strength.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A high-strength aluminum alloy material, characterized in that, The composition includes the following components by mass fraction: Si 1.00%–1.20%, Mg 1.10%–1.30%, Cu 0.90%–1.20%, Mn 0.50%–0.75%, Cr 0.10%–0.30%, Zr≤0.05%, Fe≤0.2%, Ti≤0.1%, and unavoidable impurities and balance Al.

2. The high-strength aluminum alloy material according to claim 1, characterized in that, The atomic ratio of Mg to Si is (0.85-1.15):

1.

3. The high-strength aluminum alloy material according to claim 1, characterized in that, Choose any one of the following high-strength aluminum alloy materials: (a) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.20%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (b) The composition by mass fraction includes the following components: Si 1.20%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (c) The composition includes the following components by mass fraction: Si 1.10%, Mg 1.30%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al; (d) The composition includes the following components by mass fraction: Si 1.20%, Mg 1.10%, Cu 1.00%, Mn 0.53%, Cr 0.24%, Zr 0.05%, Fe 0.18%, Ti 0.08%, and unavoidable impurities and balance Al.

4. The high-strength aluminum alloy material according to claim 1 or 2, characterized in that, The high-strength aluminum alloy material is a hollow profile.

5. The high-strength aluminum alloy material according to claim 3, characterized in that, Cavity profiles meet one or more of the following conditions: (a2) The wall thickness of the cavity profile is ≥1.5mm; (b2) The cross-sectional area of ​​the cavity profile is ≤32400mm² 2 ; (c2) The cavity profile is a single-layer cavity structure; (d2) The cross-section of the cavity profile has ≥80% similarity symmetry.

6. The method for preparing the high-strength aluminum alloy material according to any one of claims 1 to 4, characterized in that, The preparation method includes: sequentially melting the raw materials, continuous casting, homogenization treatment, extrusion, quenching, and aging treatment to obtain high-strength aluminum alloy materials.

7. The preparation method according to claim 5, characterized in that, Extrusion speed ≤10m / min; and / or The quenching and transfer time after extrusion is ≤15s.

8. The preparation method according to claim 6 or 7, characterized in that, The preparation method satisfies one or more of the following conditions: (a3) The melting temperature is 740℃~760℃; (b3) Homogenization treatment includes: a temperature of 550℃~570℃, a holding time of 7h~12h, and air cooling; (c3) The extrusion temperature is 500℃~550℃; (d3) The quenching method is online quenching; (e3) Aging treatment includes: temperature of 170℃~180℃, holding time of 7h~10h, and air cooling after removal from the furnace.

9. The preparation method according to claim 8, characterized in that, The cooling methods for homogenization, quenching, and aging are independently selected as water cooling, mist cooling, or air cooling, respectively.

10. An automotive component or battery box, characterized in that, It is made from the high-strength aluminum alloy material described in any one of claims 1 to 5.

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