High-strength high-toughness corrosion-resistant 6xxx series aluminum alloy rolling process

Abstract

The application discloses a high-strength high-toughness corrosion-resistant 6xxx series aluminum alloy rolling process and belongs to the technical field of wear-resistant and corrosion-resistant material manufacturing technologies.The 6xxx series aluminum alloy is sequentially subjected to high-temperature smelting, homogenization treatment, high-strain-rate serpentine five-pass rolling, multi-stage strengthening solid solution treatment and multi-stage aging treatment processes, so that the 6xxx series aluminum alloy has a very high proportion of small-angle grain boundaries under high-strain-rate rolling, the processing target of the high-strength high-toughness corrosion-resistant high-small-angle-grain-boundary 6xxx series aluminum alloy plate is achieved, and the aluminum alloy plate with excellent strength, elongation and corrosion resistance and other comprehensive properties is obtained.The rolling method has the advantages of relatively simple production process, low cost and easy implementation.

Description

Technical Field

[0001] This invention belongs to the field of wear-resistant and corrosion-resistant material manufacturing technology, specifically relating to a high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy rolling process. Background Technology

[0002] The 6xxx series, or Al-Mg-Si aluminum alloys, possess high specific strength, good processing and welding properties, and corrosion resistance, making them widely used in structural engineering, aerospace, and transportation industries. However, corrosion fatigue damage to aluminum alloy components is a significant factor affecting the sustainable use of aluminum alloys.

[0003] Currently, simply adding alloying elements to 6xxx series aluminum alloys can, in some cases, alter the alloy composition to improve the strength of the final aluminum alloy product, for example, by increasing the amount of silicon or copper in the alloy composition. However, increasing the concentration of silicon or copper in the alloy usually leads to the formation of precipitation at grain boundaries, which in turn reduces the corrosion resistance of the finished aluminum alloy. Existing technology, through the synergistic effect of heat treatment and processing techniques, can simultaneously improve the strength, toughness, and corrosion resistance of aluminum alloys, which is of great help in solving the application of 6xxx series aluminum alloys in automotive structures and enclosed panels.

[0004] Invention patent CN 114574737 B discloses a high-strength, high-ductility, stress corrosion-resistant bulk nanostructured aluminum alloy and its preparation method. The bulk nanostructured aluminum alloy, prepared through high-strain-rate high-speed deformation and high-temperature annealing, has a microstructure composed of equiaxed ultrafine grains ranging from 200 to 1000 nm, with the grain boundaries of the nanocrystals primarily consisting of low-energy small-angle grain boundaries. The bulk nanostructured aluminum alloy prepared by this patent exhibits a high strength-ductility ratio and excellent resistance to stress corrosion, making it suitable for the fabrication of high-strength, high-toughness structural components used in harsh corrosive environments containing chloride ions.

[0005] Invention patent CN 106967910 A introduces a high-strength Al-Zn-Mg aluminum alloy and its preparation method. The Al-Zn-Mg aluminum alloy has a room temperature tensile strength greater than 420MPa, a yield strength greater than 380MPa, and an elongation greater than 11%. It has the advantages of high strength, good plasticity, and excellent corrosion resistance. It is suitable for manufacturing the shells of portable electronic products such as tablet computers and smartphones, as well as bumpers, anti-collision beams, and crossbeams of transportation vehicles such as automobiles and rail vehicles. It has broad market application prospects. However, the addition of rare earth elements increases the cost of this solution, which is not conducive to practical production and application.

[0006] The two existing patents mentioned above improve the corrosion resistance of aluminum alloys by improving processing technology, material composition ratio, and forming different textures or precipitates. However, problems such as unsatisfactory improvement in corrosion resistance, uneven corrosion resistance, and significant impact on alloy strength still exist.

[0007] Existing research indicates that 6xxx series aluminum alloys with fibrous grains and small-angle grain boundaries exhibit superior strength, fracture toughness, and corrosion resistance. Therefore, obtaining a high proportion of small-angle grain boundaries and a low volume fraction of recrystallized microstructure is crucial for improving the overall performance of the alloy. Summary of the Invention

[0008] To address the shortcomings of the existing technology, this invention provides a rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys. By increasing the proportion of small-angle grain boundaries, the strength, fracture toughness, and corrosion resistance of 6xxx series aluminum alloys are enhanced.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0010] A rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys includes the following steps:

[0011] (1) Homogenize the 6xxx series aluminum alloy;

[0012] (2) Then, five passes of rolling are performed, with deformation amounts of 8-12%, 11-15%, 14-18%, 17-21%, and 20-24% for each pass, and a total deformation amount of 80%; the bite coefficients for each pass are 0.14, 0.16, 0.18, 0.20, and 0.21, respectively; the rolling temperature is 370℃~400℃, and the rolling strain rate for each pass is 30s. -1 ;

[0013] (3) The rolled aluminum alloy was subjected to solution treatment, water quenching treatment and aging treatment in sequence to obtain a high-strength, high-toughness and corrosion-resistant 6xxx series aluminum alloy.

[0014] The present invention uses a rolling temperature of 370℃~400℃ to improve the proportion of small-angle grain boundaries, and the grain boundary angle is mainly distributed in the range of 0° to 10°. Excessively high rolling temperature will enhance the thermal activation process, thereby inducing a certain degree of dynamic recrystallization. Dynamically recrystallized grains have large-angle grain boundaries, so the proportion of large-angle grain boundaries increases, resulting in a decrease in the proportion of small-angle grain boundaries.

[0015] The deformation amounts for each pass are 8-12%, 11-15%, 14-18%, 17-21%, and 20-24% of that for 6xxx series aluminum alloys, respectively.

[0016] As a preferred embodiment of the present invention, the rolling is serpentine rolling, which can improve the uniformity of deformation in the thickness direction of aluminum alloy strip and ensure good strip shape after rolling.

[0017] As a preferred embodiment of the present invention, the 6xxx series aluminum alloy contains Mg, Si, Cu, Mn, Fe, Zn, with the remainder being Al and trace amounts of rare earth and other alloying elements.

[0018] In a preferred embodiment of the present invention, in step (1), the aluminum alloy is quenched after homogenization treatment to achieve rapid cooling.

[0019] In a preferred embodiment of the present invention, the homogenization treatment is carried out at a temperature of 450-470°C for 24-26 hours.

[0020] As a preferred embodiment of the present invention, in step (2), the rolled aluminum alloy is immediately placed in cold water to cool it in order to preserve its deformed structure.

[0021] In a preferred embodiment of the present invention, in step (2), the ingot obtained in step (1) is heated to 370-400°C and rolled.

[0022] As a preferred embodiment of the present invention, the solution treatment is a multi-stage solution treatment, specifically: heating to 450°C and holding for 0.5 hours, then heating to 470°C and holding for 0.5 hours, and finally heating to 490°C and holding for 0.5 hours.

[0023] As a preferred embodiment of the present invention, the aging process involves maintaining the temperature at 120°C for 12 hours and then maintaining it at 150°C for 24 hours.

[0024] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention involves sequentially subjecting 6xxx series aluminum alloys to high-temperature melting, homogenization treatment, high-strain-rate serpentine rolling, strengthening solution treatment, and aging treatment, resulting in an extremely high proportion of small-angle grain boundaries under high-strain-rate rolling. This achieves the processing goal of producing high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheets with high small-angle grain boundaries, yielding aluminum alloy sheets with excellent comprehensive properties such as strength, elongation, and corrosion resistance. Furthermore, the rolling method described in this invention has the advantages of relatively simple production process, low cost, and ease of implementation. Attached Figure Description

[0025] Figure 1 This is a partial production process diagram of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy rolling process described in this invention. Detailed Implementation

[0026] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments. Example 1

[0027] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this embodiment are shown in Table 1.

[0028] Table 1

[0029]

[0030] The 6061 aluminum alloy with the composition shown in Table 1 was smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. After completion, the as-cast aluminum alloy ingot was heated to 450℃ for 24 hours for homogenization treatment to ensure uniform distribution of all elements. After rapid cooling to room temperature, the aluminum alloy ingot was heated to 370℃ and subjected to five passes of serpentine hot rolling. The first serpentine hot rolling deformation was 10 mm with a bite coefficient of 0.14; the second serpentine hot rolling deformation was 13 mm with a bite coefficient of 0.16; the third serpentine hot rolling deformation was 16 mm with a bite coefficient of 0.18; the fourth serpentine hot rolling deformation was 19 mm with a bite coefficient of 0.20; and the last serpentine hot rolling deformation was 22 mm with a bite coefficient of 0.21. The rolling strain rate for each pass should be within 30 s. -1 The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated and subjected to a multi-stage solution treatment: first, heating to 450℃ and holding for 0.5 hours; then heating to 470℃ and holding for 0.5 hours; finally, heating to 490℃ and holding for 0.5 hours. After solution treatment, it was water-quenched at room temperature. Then, a low-temperature aging treatment was performed: holding at 120℃ for 12 hours, and then at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet obtained after cooling to room temperature are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy sample. Example 2

[0031] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this embodiment are shown in Table 1.

[0032] The 6061 aluminum alloy with the composition shown in Table 1 was smelted and cast to form an aluminum alloy ingot with a thickness of 200 mm. After completion, the as-cast aluminum alloy ingot was heated to 460℃ for 25 hours for homogenization treatment to ensure uniform distribution of all elements. After rapid cooling to room temperature, the aluminum alloy ingot was heated to 380℃ and subjected to five passes of serpentine hot rolling. The first serpentine hot rolling deformation was 20 mm with a bite coefficient of 0.14; the second serpentine hot rolling deformation was 26 mm with a bite coefficient of 0.16; the third serpentine hot rolling deformation was 32 mm with a bite coefficient of 0.18; the fourth serpentine hot rolling deformation was 38 mm with a bite coefficient of 0.20; and the last serpentine hot rolling deformation was 44 mm with a bite coefficient of 0.21. The rolling strain rate for each pass should be within 30 s. -1 The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated for a multi-stage solution treatment: first, heating to 450℃ and holding for 0.5 hours; then heating to 470℃ and holding for 0.5 hours; finally, heating to 490℃ and holding for 0.5 hours. After solution treatment, it was water-quenched at room temperature. Then, a low-temperature aging treatment was performed: holding at 120℃ for 12 hours, then at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet obtained after cooling to room temperature are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy sample. Example 3

[0033] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this embodiment are shown in Table 3.

[0034] Table 3

[0035]

[0036] The 6082 aluminum alloy with the composition shown in Table 3 was smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. After completion, the as-cast aluminum alloy ingot was heated to 470℃ for 26 hours for homogenization treatment to ensure uniform distribution of all elements. After rapid cooling to room temperature, the aluminum alloy ingot was heated to 390℃ and subjected to five passes of serpentine hot rolling. The first serpentine hot rolling deformation was 10 mm with a bite coefficient of 0.14; the second serpentine hot rolling deformation was 13 mm with a bite coefficient of 0.16; the third serpentine hot rolling deformation was 16 mm with a bite coefficient of 0.18; the fourth serpentine hot rolling deformation was 19 mm with a bite coefficient of 0.20; and the last serpentine hot rolling deformation was 22 mm with a bite coefficient of 0.21. The rolling strain rate for each pass should be within 30 s. -1The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated for a multi-stage solution treatment: first, heating to 450℃ and holding for 0.5 hours; then heating to 470℃ and holding for 0.5 hours; finally, heating to 490℃ and holding for 0.5 hours. After solution treatment, it was water-quenched at room temperature. Then, a low-temperature aging treatment was performed: holding at 120℃ for 12 hours, then at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet obtained after cooling to room temperature are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy sample.

[0037] Comparative Example 1

[0038] The chemical composition and weight percentage of a high-strength, high-toughness, corrosion-resistant, high-small-angle grain boundary 6xxx series aluminum alloy sheet are shown in Table 1.

[0039] The 6061 aluminum alloy with the composition shown in Table 1 was smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. After completion, the as-cast aluminum alloy was heated to 565℃ for 3 hours for high-temperature solution treatment to ensure uniform distribution of all elements. Subsequently, it was hot-rolled once at a temperature of 370℃, with a total deformation of 80% and a rolling deformation rate of 10 s. -1 The aging temperature was 380℃ and the time was 30min. The yield strength, tensile strength, elongation and small-angle grain boundary ratio of the final aluminum alloy are shown in Table 2.

[0040] Comparative Example 2

[0041] The only difference between the preparation method of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example and Example 1 is that the rolling strain rate for each rolling pass should be within 10 s. -1 .

[0042] Comparative Example 3

[0043] The only difference between the preparation method of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example and Example 1 is that the rolling strain rate for each rolling pass should be within 40 s. -1 .

[0044] Comparative Example 4

[0045] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example are shown in Table 1.

[0046] The 6061 aluminum alloy with the composition shown in Table 1 was smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. After completion, the as-cast aluminum alloy ingot was heated to 450℃ for 24 hours for homogenization treatment to ensure uniform distribution of all elements. After rapid cooling to room temperature, the aluminum alloy ingot was heated to 370℃ and subjected to four passes of serpentine hot rolling. The first serpentine hot rolling deformation was 10 mm with a bite coefficient of 0.14; the second serpentine hot rolling deformation was 13 mm with a bite coefficient of 0.16; the third serpentine hot rolling deformation was 16 mm with a bite coefficient of 0.18; and the fourth serpentine hot rolling deformation was 19 mm with a bite coefficient of 0.20. The rolling strain rate for each pass should be within 30 s⁻¹. -1 The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated for a multi-stage solution treatment: first, heating to 450℃ and holding for 0.5 hours; then heating to 470℃ and holding for 0.5 hours; finally, heating to 490℃ and holding for 0.5 hours. After solution treatment, it was water-quenched at room temperature. Then, a low-temperature aging treatment was performed: holding at 120℃ for 12 hours, then at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet obtained after cooling to room temperature are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy sample.

[0047] Comparative Example 5

[0048] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example are shown in Table 1. The only difference between the preparation method and Example 1 is that the aluminum alloy ingot is heated to 560°C and subjected to five passes of serpentine hot rolling.

[0049] Comparative Example 6

[0050] The only difference between the preparation method of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example and Example 1 is that the aluminum alloy ingot is not heated, but is directly rolled in multiple passes using a four-roll cold rolling mill until the ingot is processed into a 20mm sheet.

[0051] Comparative Example 7

[0052] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example are shown in Table 1.

[0053] The 6061 aluminum alloy with the composition shown in Table 1 was smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. After completion, the as-cast aluminum alloy ingot was heated to 450℃ for 24 hours for homogenization treatment to ensure uniform distribution of all elements. After rapid cooling, the aluminum alloy ingot was heated to 370℃ and subjected to five passes of serpentine hot rolling. The first serpentine hot rolling deformation was 10 mm with a bite coefficient of 0.14; the second serpentine hot rolling deformation was 13 mm with a bite coefficient of 0.16; the third serpentine hot rolling deformation was 16 mm with a bite coefficient of 0.18; the fourth serpentine hot rolling deformation was 19 mm with a bite coefficient of 0.20; and the last serpentine hot rolling deformation was 22 mm with a bite coefficient of 0.21. The rolling strain rate for each pass should be within 30 s. -1 The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated to 490℃ and held for 1.5 hours for solution treatment, followed by water quenching at room temperature. A low-temperature aging treatment was then performed: held at 120℃ for 12 hours, and then at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the obtained high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy samples.

[0054] Comparative Example 8

[0055] The chemical composition and weight percentage of the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet described in this comparative example are shown in Table 1.

[0056] The 6061 aluminum alloy with the composition shown in Table 1 is smelted and cast to form an aluminum alloy ingot with a thickness of 100 mm. The preheated flat ingot is then subjected to hot continuous rolling, with the hot roughing rolling consisting of 5 passes. The reduction per pass in the hot roughing rolling is ≥50 mm, and the rolling strain rate of the last two passes in the hot roughing rolling should be ≥30 s. -1 The rolled sheet was immediately placed in cold water to cool and preserve its post-deformation microstructure. It was then heated and subjected to a multi-stage solution treatment: first, heating to 450℃ and holding for 0.5 hours; then heating to 470℃ and holding for 0.5 hours; finally, heating to 490℃ and holding for 0.5 hours. After solution treatment, it was water-quenched at room temperature. Then, a low-temperature aging treatment was performed: holding at 120℃ for 12 hours, and then holding at 150℃ for 24 hours. The yield strength, tensile strength, elongation, and small-angle grain boundary ratio of the obtained high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheet are shown in Table 2. The small-angle grain boundary ratio was obtained from the EBSD grain boundary diagram and the corresponding inverse pole figure of the alloy sample.

[0057] Table 2

[0058]

[0059] As shown in Table 2, the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy sheets prepared in Examples 1-3 have better yield strength, tensile strength, elongation, and corrosion resistance than those in Comparative Examples 1-8, indicating that the 6xxx series aluminum alloys prepared by the high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloy rolling process described in this invention have superior performance.

[0060] As shown in Examples 1 and Comparative Examples 2 and 3, the rolling strain rate is crucial for increasing the proportion of small-angle grain boundaries. When the strain rate is low, the deformation time is relatively long, allowing sufficient time for the precipitates to nucleate and grow, resulting in larger precipitate density and size. Increasing the strain rate intensifies dislocation multiplication and increases dislocation density, easily leading to the formation of high-density dislocation cells. Simultaneously, the shortened deformation process suppresses the nucleation process of dynamic recrystallization, increasing the proportion of small-angle grain boundaries. However, excessively high deformation rates make grain coarsening and grain boundary slip more likely, thereby reducing the mechanical properties of the metal.

[0061] As shown in Example 1 and Comparative Example 4, the alloy material obtained by four-pass rolling in Comparative Example 4 has a low proportion of small-angle grain boundaries, and its yield strength, tensile strength, elongation, and corrosion resistance are all significantly reduced. With the increase of rolling passes, the metal bonding becomes denser, and the tensile strength and elongation increase accordingly.

[0062] As shown in Example 1 and Comparative Example 5, Comparative Example 5 involved heating an aluminum alloy ingot to 560°C and performing a five-pass serpentine hot rolling process. The resulting alloy material exhibited a low proportion of small-angle grain boundaries, indicating that the thermal activation process intensifies with increasing rolling temperature, thereby inducing a certain degree of dynamic recrystallization. Since dynamically recrystallized grains have large-angle grain boundaries, the proportion of large-angle grain boundaries increases, leading to a decrease in the proportion of small-angle grain boundaries. Furthermore, at higher rolling temperatures, grains grow significantly during short-term solidification, resulting in a significant reduction in the fine-grain strengthening effect and a decrease in mechanical properties.

[0063] As shown in Example 1 and Comparative Example 6, a rolling temperature of 370°C to 400°C is beneficial for increasing the proportion of small-angle grain boundaries, with the grain boundary angles mainly distributed between 0° and 10°. If cold rolling is used, not only does the production process consume a large amount of energy and manpower, resulting in high production costs, but the material's plasticity is also significantly limited, leading to low processing efficiency and long processing time, making it difficult to meet the demands of rapid production. Furthermore, the cold rolling process causes deformation of the sheet metal, increases internal stress, and reduces the material's physical and mechanical properties.

[0064] As demonstrated in Example 1 and Comparative Example 7, staged solution treatment is more thorough. Through sufficient staged solution treatment, the content of harmful substances such as non-metallic inclusions and oxides in the material can be reduced, thereby improving the material's corrosion resistance. It can also ensure a uniform distribution of solute elements in the solid solution, enhancing the strength and hardness of the crystals and increasing the tensile strength and yield strength of the metal.

[0065] According to Example 1 and Comparative Example 8, Comparative Example 8 underwent ordinary multi-pass rolling treatment, resulting in an alloy material with a low proportion of small-angle grain boundaries, and significantly reduced yield strength, tensile strength, elongation, and corrosion resistance. In serpentine rolling, the equivalent deformation of the lower layer of the plate is greater than that of the upper layer, and the difference in deformation between the upper and lower layers increases with the increase of the velocity ratio. Furthermore, due to the presence of the "rolling zone," the shear strain in the core of the thick plate is much greater than that in symmetrical rolling, and the shear deformation in the core of the plate increases with the increase of the velocity ratio and the amount of dislocation. This additional shear deformation is beneficial for the deformation to penetrate into the core of the thick plate, thereby improving the non-uniformity of the high-axis deformation of the thick plate.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. 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 essence and scope of the technical solutions of the present invention.

Claims

1. A rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys, characterized in that, Includes the following steps: (1) Homogenize the 6xxx series aluminum alloy; (2) Then, five passes of rolling are performed, with deformation amounts of 8-12%, 11-15%, 14-18%, 17-21%, and 20-24% for each pass, and a total deformation amount of 80%; the bite coefficients for each pass are 0.14, 0.16, 0.18, 0.20, and 0.21, respectively; the rolling temperature is 370℃~400℃, and the rolling strain rate for each pass is 30s. -1 ; (3) The rolled aluminum alloy was subjected to solution treatment, water quenching treatment and aging treatment in sequence to obtain a high-strength, high-toughness and corrosion-resistant 6xxx series aluminum alloy; The rolling process is a serpentine rolling process; The 6xxx series aluminum alloys contain the following elements: Mg, Si, Cu, Mn, Fe, Zn, with the remainder being Al and trace amounts of rare earth and other alloying elements.

2. The rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys as described in claim 1, characterized in that, In step (1), the aluminum alloy is quenched after homogenization treatment.

3. The rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys as described in claim 1, characterized in that, In step (2), the rolled aluminum alloy is placed in cold water to cool.

4. The rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys as described in claim 1, characterized in that, The solution treatment is a multi-stage solution treatment, specifically: heating to 450℃ and holding for 0.5h, then heating to 470℃ and holding for 0.5h, and finally heating to 490℃ and holding for 0.5h.

5. The rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys as described in claim 1, characterized in that, The aging process involves maintaining the temperature at 120°C for 12 hours, followed by maintaining it at 150°C for 24 hours.

6. The rolling process for high-strength, high-toughness, and corrosion-resistant 6xxx series aluminum alloys as described in claim 1, characterized in that, The homogenization process is carried out at a temperature of 450-470℃ for 24-26 hours.

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