Manufacturing method for 6xxx series aluminum alloys using thin gauges

Abstract

This specification provides highly formable aluminum alloys and methods for producing such alloys. The methods for preparing aluminum alloys described herein may include a cold working thickness reduction following a solution heat treatment step for producing aluminum alloy products exhibiting improved formability. The methods described herein result in aluminum alloys having a relatively soft composition, allowing for improved formability by reducing the number of passes during hot and cold mill rolling compared to conventional AA5182 aluminum alloys used to produce can end materials. Reducing the number of passes required to produce aluminum alloy products with a desired gauge can reduce carbon emissions and energy consumption associated with the production of aluminum alloy products.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 511,819, filed on July 3, 2023, which is hereby incorporated by reference in its entirety for all purposes and intentions.

[0002] This disclosure relates to materials science, materials chemistry, metallurgy, aluminum alloys, aluminum alloy products, aluminum manufacturing, and related fields. More specifically, this disclosure relates to 6xxx - series aluminum alloys that exhibit high strength and formability at a thin gauge. Aluminum alloys of the 6xxx series with a thin gauge can be used to manufacture, for example, can tabs, can bodies, and can ends of beverage cans.

Background Art

[0003] The material for can ends has conventionally been manufactured from high - strength aluminum alloys having good forming characteristics. The mechanical requirements for the aluminum alloy used to manufacture the material for can ends are different from those for the material of the can body. Generally, the aluminum alloy for manufacturing the material for can ends requires higher strength than the material of the can body. As a result, the material for can ends is often manufactured from aluminum alloys containing a large amount of magnesium (Mg). For example, the material for can ends can be manufactured from a highly designed AA5l82 aluminum alloy having a precisely controlled composition and alloy manufacturing process.

[0004] Many aluminum manufacturers use AA5182 aluminum alloy for the can end material. The composition of AA5182 is strictly controlled so that the magnesium (Mg) content is 4.0 wt.% to 5.0 wt.%, the manganese (Mn) content is 0.2 wt.% to 0.5 wt.%, the maximum iron (Fe) content is 0.35 wt.%, the maximum silicon (Si) content is 0.2 wt.%, the maximum copper (Cu) content is 0.15 wt.%, and the maximum chromium (Cr) content is 0.1 wt.%. However, it is difficult to improve the performance of one property (e.g., strength) of 5xxx series aluminum without degrading the performance of other properties (e.g., formability). If the Mg content of AA5182 is increased beyond 5 wt.% to improve strength and / or formability, the aluminum alloy becomes very susceptible to cracking during the manufacturing process. Furthermore, a relatively high Mg content can hinder the recovery of aluminum alloys and reduce the reusability and recyclability of aluminum alloy products. [Overview of the project]

[0005] The embodiments of the invention that are included are defined by the claims, not by this abstract. This abstract is a higher-level summary of various aspects of the invention and introduces some concepts that are further described in the sections on embodiments for carrying out the invention below. This abstract is not intended to identify any important or essential features of the claimed subject matter, nor is it intended to be used alone to determine the scope of the claimed subject matter. The subject matter should be understood by referring to the entire specification, any or all of the drawings, and the appropriate parts of each claim.

[0006] This specification provides highly formable 6xxx series aluminum alloys and methods for producing thin gauge aluminum alloys. The aluminum alloys described herein contain 0.20 to 1.40 wt.% Si, 0.20 to 0.80 wt.% Fe, 0.05 to 1.00 wt.% Cu, 0.05 to 0.80 wt.% Mn, 0.50 to 1.60 wt.% Mg, up to 0.25 wt.% Zn, up to 0.30 wt.% Cr, up to 0.60 wt.% Bi, up to 0.60 wt.% Pb, up to 0.15 wt.% impurities, and the remainder Al. In some embodiments, the aluminum alloy contains 0.60 to 1.10 wt.% Si, up to 0.40 wt.% Fe, 0.50 to 0.90 wt.% Cu, 0.10 to 0.45 wt.% Mn, 0.50 to 1.00 wt.% Mg, up to 0.15 wt.% Zn, up to 0.10 wt.% Cr, up to 0.05 wt.% Bi, up to 0.05 wt.% Pb, up to 0.15 wt.% impurities, and the remainder Al.

[0007] In some embodiments, a method for manufacturing aluminum alloy products is provided. The method comprises casting an aluminum alloy to manufacture a cast aluminum alloy product, wherein the aluminum alloy includes 6xxx series aluminum alloys; homogenizing the cast aluminum alloy product to manufacture a homogenized cast aluminum alloy product; hot rolling the homogenized cast aluminum alloy product to manufacture a hot-rolled product; optionally i) solution heat treating the hot-rolled product at a solution heat treatment temperature of approximately 450°C to 600°C, or ii) coiling the hot-rolled product at the hot-rolling outlet temperature; cold rolling the hot-rolled product to manufacture a cold-rolled product, wherein the cold-rolled product is rolled to a final gauge thickness of 0.180 mm to 0.250 mm, and the outlet temperature of the cold-rolled product is 150°C or higher; and optionally solution heat treating the cold-rolled product at a solution heat treatment temperature of approximately 450°C to 580°C.

[0008] In some embodiments, the method further comprises coiling a cold-rolled product to produce a coiled aluminum alloy product, the cold-rolled product being configured to undergo precipitation hardening during coil cooling. In some embodiments, the method further comprises aging the coiled aluminum alloy product at a temperature of 150°C to 250°C for 1 to 10 hours. In some embodiments, the casting step includes direct chill casting. In some embodiments, the homogenization step is carried out at a homogenization temperature of about 540°C to 600°C. In some embodiments, the hot-rolled product is cooled to near ambient temperature before the solution heat treatment step. In some embodiments, the solution heat treatment step includes heating the hot-rolled product at the solution heat treatment temperature for up to 50 seconds before the cold-rolling step. In some embodiments, the line speed for the solution heat treatment step is at least 20 meters / minute.

[0009] In some embodiments, the inlet temperature of the hot-rolled product into the cold-rolling process is 20°C to 80°C. In some embodiments, the cold-rolling process includes six or fewer cold-rolling passes to produce the cold-rolled product. Furthermore, in some embodiments, the method further includes solution heat treatment of the cold-rolled product between at least two cold-rolling passes. In some embodiments, the method does not include artificial aging after the cold-rolling process. In some embodiments, the cold-rolling process is carried out in a cold-rolling mill including at least two stands arranged in series. In some embodiments, the cold-rolling process includes one pass to produce the cold-rolled product. In some embodiments, the outlet temperature of the cold-rolled product is about 150°C to 220°C. In some embodiments, the cold-rolling process results in at least an 80% reduction in cold-work thickness from the hot-rolled product to the cold-rolled product. In some embodiments, the cold-rolling process results in about an 85% to 95% reduction in cold-work thickness. In some embodiments, the method further includes solution heat treatment of the cold-rolled product.

[0010] In some embodiments, the hot rolling process is configured to produce a hot-rolled product having a hot band gauge of about 0.5 mm to 3.5 mm. In some embodiments, the hot rolling process is characterized by using 21 or fewer passes to produce the hot-rolled product. In some embodiments, precipitation hardening is configured to occur using residual heat corresponding to the exit temperature of the cold-rolled product. In some embodiments, the method further includes coating a coiled aluminum alloy product. In some embodiments, the aluminum alloy product has a yield strength of about 150 MPa to 425 MPa. In some embodiments, the aluminum alloy product has an elongation of 1% to 20%.

[0011] Furthermore, this specification also provides aluminum alloy products (e.g., aluminum alloy can end material, aluminum alloy can tab material, or aluminum alloy can body material) that include the aluminum alloy described herein. In some embodiments, the aluminum alloy product includes at least 20 wt.% recycled aluminum material. In some embodiments, the recycled aluminum material includes used beverage can scrap.

[0012] Further aspects, purposes, and advantages will become apparent upon consideration of the detailed description of the non-limiting examples that follow.

[0013] This disclosure will be readily understood by the following detailed description in conjunction with the attached drawings. In the drawings, similar reference numerals indicate similar structural elements. [Brief explanation of the drawing]

[0014] [Figure 1] This is a schematic diagram illustrating the processing method described herein, which includes a cold rolling step after a solution heat treatment step. [Figure 2] Table 2 shows a graph illustrating the effect of the processing steps on the conductivity of exemplary aluminum alloys, measured according to the International Association of Copper Standards (IACS). [Figure 3]This bar graph shows the yield strength, broadening, and elongation of the aluminum alloy described herein after undergoing a solution heat treatment process at approximately 560°C. [Figure 4] This bar graph shows the yield strength and broadness of the aluminum alloy described herein after undergoing a solution heat treatment process at approximately 540°C. [Figure 5] The graph shows the whiteness values ​​of alloy 2 from the example and alloy 1 (AA5182 alloy) from the comparative example, as measured by a spectrophotometer. [Figure 6] The graph shows the glossiness of alloy 2 from the example and alloy 1 from the comparative example at 60°, as measured by a spectrophotometer. [Figure 7] The graphs show the yield strength (MPa), maximum tensile strength (MPa), and elongation properties (%) of alloy 2 in examples after different processing conditions. [Figure 8] The graphs show the propagation energy (KJ / m2) for alloy 2 of the example and alloy 1 of the comparative example, as measured by the Kahn tear test. [Figure 9] The graphs show the shell buckling strength (psi) of alloy 2 in the example and alloy 1 in the comparative example. [Figure 10] The graphs show the fresh buckling strength (psi) of alloy 2 in the example and alloy 1 in the comparative example. [Figure 11] The graphs show the turbo-aging buckling strength (psi) of alloy 2 in the example and alloy 1 in the comparative example. [Figure 12] The graphs show the results of the clamping pressure formability of the shells of alloy 2 in the example and comparative example 1. [Modes for carrying out the invention]

[0015] This specification describes 6xxx series aluminum alloys (for example, for can end materials, can tab materials, or can body materials) and methods for preparing 6xxx series aluminum alloys. The 6xxx series aluminum alloys described herein provide a cost-effective alternative to the use of AA5182 aluminum alloy for can end materials. The 6xxx series aluminum alloys exhibit high strength and formability at thin gauges (e.g., less than 10 mm) while having a lower Mg content than conventional AA5182 aluminum alloys. The low Mg content of the 6xxx series aluminum alloys described herein allows for a reduction in the amount and cost of Mg addition to can end materials. Specifically, because of the low Mg content, the 6xxx series aluminum alloys described herein can be manufactured from a larger amount of recycled aluminum material than AA5182 aluminum alloys. Furthermore, the method for preparing 6xxx series aluminum alloys described herein reduces the total number of hot-rolling passes required to achieve a predetermined gauge (e.g., the gauge of can end material) compared to AA5182 aluminum alloy, thereby providing processing efficiency and reducing the amount of resources and time required for hot-rolling, which is a time and resource-intensive process in aluminum alloy manufacturing. In some non-limiting examples, the method for preparing highly formable aluminum alloy sheets includes a cold-rolling process of six or fewer passes to produce a cold-rolled product.

[0016] Traditionally, AA5182 aluminum alloy has been used to manufacture can end caps. 6xxx series aluminum alloys have not been used for can end caps because their mechanical properties (e.g., formability) are unsuitable for thin gauge (e.g., less than 10 mm) can end caps. AA5182 aluminum alloy for can end caps requires a strictly controlled composition to meet the minimum strength requirements of can end caps while maintaining formability for manufacturing complex shapes. Generally, aluminum alloys used for can end caps require higher strength than the can body material; therefore, such can end caps are instructed to be manufactured from aluminum alloys containing high amounts of Mg, such as AA5182 aluminum alloy. This limits the amount of recycled aluminum material that can be used to manufacture AA5182 aluminum alloy. The high Mg content in conventional AA5182 aluminum alloys for can end caps can limit the recyclability of AA5182 aluminum alloy due to poor recovery rates resulting from its relatively high Mg content. Aluminum alloy products formed using AA5182 aluminum alloy also experience a decrease in end buckling strength after forming, due to the age-induced softening effect caused by the high Mg content of AA5182 aluminum alloy.

[0017] The 6xxx series aluminum alloy described in this specification can effectively replace the AA5182 aluminum alloy for manufacturing can end stock materials. The 6xxx series aluminum alloy described in this specification beneficially reduces the back-end performance (end buckling strength) in down-gauging, eliminates the age softening at the end, and prevents / reduces the loss of end buckling strength over time. Further, the 6xxx series aluminum alloy described in this specification improves the manufacturing recycle content of the can end stock materials and improves the control of the recycled alloy when using UBC integrated with the 6xxx series aluminum alloy. The method described in this specification manufactures a 6xxx series aluminum alloy that can be down-gauged to a thickness suitable for the can end stock materials used in the manufacture of can ends. The 6xxx series aluminum alloy is generally described herein with respect to the materials for can ends, but the 6xxx series aluminum alloy can be used for other beverage can applications such as tab materials used to manufacture tabs or can body materials used to manufacture can bodies. In some embodiments, the method includes cold rolling after solutionizing (e.g., cold rolling an aluminum alloy product after solution heat treatment). This method includes solution heat treating a hot rolled product (manufactured from a 6xxx series aluminum alloy) to produce a solution heat treated hot rolled product, cold rolling the solution heat treated hot rolled product to produce a cold rolled product, and aging the cold rolled product. In some embodiments, the hot rolled product may be solution heat treated and then cold rolled to reduce the thickness of the hot rolled product by more than 80% to the final gauge.

[0018] 6xxx series aluminum alloys offer processing advantages compared to conventional AA5182 aluminum alloys due to their softer state (lower strength). This softer state of 6xxx series aluminum alloys can correspond to a 20-30% lower yield strength compared to conventional AA5182 aluminum alloys. For example, conventional AA5182 aluminum alloys of grade F, due to their high Mg content, can exhibit a yield strength of approximately 200 MPa. In contrast, naturally aged AA6111 aluminum alloys of grade T4 exhibit a yield strength of 135 MPa. Consequently, the rolling process for AA5182 aluminum alloys takes considerably longer compared to 6xxx series aluminum alloys. In some cases, the softer state of 6xxx series aluminum alloys compared to conventional AA5182 aluminum alloys allows for energy reduction in the manufacturing of aluminum alloys, such as reducing the number of passes during hot and cold mill rolling. High-strength aluminum alloys (e.g., AA5182 aluminum alloy) typically require relatively high mill power to reduce the thickness of the high-strength aluminum alloy to a desired thickness, such as for use as a material for can ends. Therefore, the softer state of the 6xxx series aluminum alloys described herein can reduce the carbon footprint and energy consumption associated with the manufacture of the aluminum alloy while lowering manufacturing or processing costs.

[0019] Furthermore, the 6xxx series aluminum alloys described herein exhibit similar mechanical properties to conventional AA5182 aluminum alloys, allowing can manufacturers to use them with little to no modification to existing methods. In some embodiments, a larger volume of used beverage cans can be used to manufacture the 6xxx series aluminum alloys described herein, thereby reducing the amount of primary aluminum required, lowering overall costs, and maintaining equivalent or superior rolling productivity. In some embodiments, the 6xxx series aluminum alloys described herein can be used to manufacture can end material for can ends, can tab material for tabs, or can body material for can bodies.

[0020] Definitions and Explanation As used herein, the terms "invention", "the invention", "this invention", and "the present invention" are intended to broadly refer to the subject matter of this patent application and all of the following claims. It should be understood that phrases containing these terms neither limit the subject matter described herein nor limit the meaning or scope of the following claims.

[0021] In this description, reference is made to alloys identified by aluminum industry designations such as "system" or "6xxx". For an understanding of the numbering system most commonly used for the naming and identification of aluminum and its alloys, reference may be made to either "International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys" or "Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot", both of which are issued by the Aluminum Association.

[0022] As used herein, the meaning of "a", "an", or "the" includes references to both the singular and the plural unless the context clearly indicates otherwise.

[0023] As used herein, a plate generally has a thickness exceeding about 15 mm. For example, a plate may refer to an aluminum product having a thickness exceeding about 15 mm, about 20 mm, about 25 mm, about 30 mm, about 35 mm, about 40 mm, about 45 mm, about 50 mm, or about 100 mm.

[0024] As used herein, shades (also called sheet plates) generally have a thickness of about 4 mm to about 15 mm. For example, shades may have a thickness of about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm.

[0025] As used herein, a sheet generally refers to an aluminum product having a thickness of less than approximately 4 mm (for example, less than 3 mm, less than 2 mm, less than 1 mm, less than 0.5 mm, less than 0.3 mm, or less than 0.1 mm). For example, the sheets may have thicknesses of approximately 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, or 3.9 mm.

[0026] As used herein, formability refers to the ability of a material to deform into a desired shape without the occurrence of forming errors such as fracture, tearing, necking, ear formation, or wrinkles, springback, or galling. In engineering, formability can be classified according to the mode of deformation. Examples of deformation modes include drawing, stretching, bending, and stretch flanging.

[0027] This application makes references to alloy tempers or states. For an understanding of the most commonly used descriptions of alloy tempers, please refer to "American National Standards (ANSI) H35 on Alloy and Temper Designation Systems". State F or temper refers to the as-manufactured aluminum alloy. State O or temper refers to the annealed aluminum alloy. State T1 or temper refers to the aluminum alloy that has been cooled from hot working and naturally aged (e.g., at room temperature). State T2 or temper refers to the aluminum alloy that has been cooled from hot working, cold working, and naturally aged. State T3 or temper refers to the aluminum alloy that has been solution-treated, cold working, and naturally aged. State T4 or temper refers to the aluminum alloy that has been solution-treated and naturally aged. State T5 or temper refers to the aluminum alloy that has been cooled from hot working and artificially aged (by heating). State T6 or temper refers to the aluminum alloy that has been solution-treated and artificially aged. T7 state or temper refers to aluminum alloy that has been solution-treated and artificially overaged. T8x state or temper refers to aluminum alloy that has been solution-treated, cold-worked and artificially aged. T9 state or temper refers to aluminum alloy that has been solution-treated, artificially aged and cold-worked. W state or temper refers to aluminum alloy after solution treatment.

[0028] As used herein, the meaning of “room temperature” may include temperatures between approximately 15°C and approximately 30°C, such as approximately 15°C, approximately 16°C, approximately 17°C, approximately 18°C, approximately 19°C, approximately 20°C, approximately 21°C, approximately 22°C, approximately 23°C, approximately 24°C, approximately 25°C, approximately 26°C, approximately 27°C, approximately 28°C, approximately 29°C, or approximately 30°C.

[0029] As used herein, terms such as “cast aluminum alloy products,” “cast aluminum alloys,” “cast metal products,” and “cast products” are interchangeable and refer to products manufactured by direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (including, for example, by the use of a twin-belt caster, twin-roll caster, block caster, or any other continuous caster), electromagnetic casting, hot-top casting, or any other casting method, or any combination thereof.

[0030] All disclosures herein should be understood to include both endpoints and any subranges contained therein. For example, the stated range "1 to 10" should be understood to include all subranges between these values, including the minimum value 1 to the maximum value 10, i.e., all subranges starting with a minimum value greater than or equal to 1 (e.g., 1 to 6.1) and ending with a maximum value less than or equal to 10 (e.g., 5.5 to 10).

[0031] The following aluminum alloys are described in terms of their elemental composition in weight percentage (wt.%) based on the total weight of the alloy. In specific examples of each alloy, the remainder is aluminum, and the maximum wt.% of the total impurities is 0.15%.

[0032] Manufacturing method for aluminum alloy products This specification describes novel methods for preparing aluminum alloy products exhibiting desirable mechanical properties. In some embodiments, the methods described herein produce 6xxx series aluminum alloys for use as can end material, can tab material, or can body material. For example, the methods described herein produce 6xxx series aluminum alloys for use as can end material for manufacturing can ends, can tab material for manufacturing tabs, and can body material for manufacturing can bodies. In some embodiments, the methods described herein produce 6xxx series aluminum alloys that can be rolled to a thin gauge (e.g., less than 0.3 mm thick) for use as can end material, can tab material, or can body material. Conventionally, 6xxx series aluminum alloys have not been offered in thin gauges because these alloys do not achieve good mechanical properties (e.g., a combination of strength and formability) due to the thin gauge and processing inefficiencies. For example, continuous annealing and solution heat treatment of 6xxx series aluminum alloys in thin gauges (e.g., less than 0.3 mm thick) is extremely difficult and uneconomical. Secondly, 6xxx series aluminum alloys must be supplied to customers in T4 temper for molding purposes, requiring further heat treatment to T6 temper. For this reason, 6xxx series aluminum alloys are undesirable for use as a material for can bodies. These factors have prevented the use of 6xxx series aluminum alloys in thin gauges as a material for can bodies.

[0033] Remarkably, the method described herein provides a precisely controlled process for producing 6xxx series aluminum alloys that achieve good strength and formability properties at thin gauges. The process for producing 6xxx series aluminum alloys at thin gauges involves heat-treating the 6xxx series aluminum alloy at a thicker gauge (e.g., 0.5 mm to 2.5 mm) before carrying out a cold-rolling process to achieve the thin gauge. For example, the method may involve solution heat treatment of the hot-rolled product. Thus, instead of supplying coils of 6xxx series aluminum alloys of T4 quality for subsequent heat treatment by the customer, the 6xxx series aluminum alloy can be supplied as heat-treated sheets, avoiding post-forming heat treatment processes that can cause deformation of the 6xxx series aluminum alloy. Furthermore, because 6xxx series aluminum alloys have a lower Mg content compared to AA5182 aluminum alloys, they do not exhibit softening due to aging at the edges, which is a common problem for can end materials.

[0034] In some embodiments, the method includes casting, homogenization, hot rolling, solution heat treatment, cold rolling, and aging for the production of aluminum alloy products. In one exemplary embodiment, an aluminum alloy is cast to produce a cast aluminum alloy product, the cast aluminum alloy product is homogenized to form a homogenized aluminum alloy product, the homogenized aluminum alloy product is subjected to one or more hot rolling passes to produce a hot-rolled product, the hot-rolled product is solution heat treated to produce a solution-treated hot-rolled product, and the solution-treated hot-rolled product is cold-rolled to produce an aluminum alloy product. In some embodiments, the cold-rolling process results in a thickness reduction of more than 80% to the final gauge. In some embodiments, the final gauge of the aluminum alloy product may be less than 0.30 mm (e.g., 0.180 mm to 0.250 mm). The thickness reduction by cold rolling after solution heat treatment provides a thin-gauge aluminum alloy exhibiting a combination of strength and formability for use as a material for can end parts.

[0035] Cold rolling can increase the sheet strength of aluminum alloy products through work hardening. Furthermore, cold rolling can contribute to a combination of strength and formability of thin-gauge aluminum alloys by providing dislocations as nuclei for precipitation hardening. For example, cold rolling can stretch aluminum alloy products and add dislocations to the granular structure of the aluminum alloy product to improve strength while maintaining formability for recovery from relatively slow cooling. By cooling hot-rolled products relatively slowly, precipitates that limit or hinder further deformation can be grown in the microstructure of the aluminum alloy, thereby maintaining or improving the strength of the aluminum alloy after cold rolling. Optionally, the aluminum alloy product is subjected to additional processing steps, as described below, to form the aluminum alloy article. In some embodiments, the aluminum alloy product can be used for can end material applications. In additional or alternative embodiments, the aluminum alloy product can be used for can tab material applications or can body material applications.

[0036] Among other properties, the method for preparing aluminum alloys described herein yields aluminum alloy products exhibiting desirable elongation and formability. In some cases, mechanical properties attributable to the method of processing the aluminum alloy can be achieved. For example, as further described herein, the processing method may include a hot rolling step using 21 or fewer passes, a cold rolling step using 6 or fewer passes, and a solution heat treatment step at a solution heat treatment temperature of about 450°C to 580°C. The resulting aluminum alloy product exhibits desirable formability. In certain embodiments, the method for preparing and processing the aluminum alloy product can influence, or even determine, whether the product has properties suitable for a desired application.

[0037] casting As further described herein, aluminum alloys can be cast into cast aluminum alloy products using any suitable casting method. For example, the casting process may include a direct chill (DC) casting process or a continuous casting (CC) process. In some non-limiting examples, the aluminum alloy for use in the casting process may be a primary material produced from raw materials (e.g., refined aluminum and additional alloying elements). In some further examples, the aluminum alloy for use in the casting process may be a recycled material produced at least partially from aluminum scrap and optionally in combination with the primary material. In some cases, the aluminum alloy for use in the casting process may contain at least about 40% recycled content. For example, the aluminum alloy for use in the casting process may contain at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 95% recycled content.

[0038] In some embodiments, the continuous casting system may include a pair of movable opposing casting surfaces (e.g., movable opposing belts, rolls, or blocks), a casting cavity between the pair of movable opposing casting surfaces, and a molten metal injector. The molten metal injector may have an end opening from which molten metal can exit the injector and be injected into the casting cavity. The cast aluminum alloy product (e.g., a cast ingot, a cast slab, or other cast product) can be processed by any desired technique. The cast aluminum alloy product can then be subjected to further processing steps. For example, the processing methods described herein may include homogenization, hot rolling, solution heat treatment, cold rolling, and / or aging steps to obtain an aluminum alloy product.

[0039] homogenization The homogenization process described herein is designed for the aluminum alloys described herein. The homogenization process may include heating a cast aluminum alloy product to a temperature of about 400°C to about 600°C (e.g., about 400°C to about 500°C, about 450°C to about 550°C, 450°C to about 580°C, about 540°C to about 600°C, or about 570°C to about 600°C) in order to produce a homogenized cast aluminum alloy product. For example, a cast aluminum alloy product can be heated to a temperature of 400°C, 410°C, 420°C, 430°C, 440°C, 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, or 600°C. In some embodiments, heating the cast aluminum alloy takes up to about 15 hours (e.g., about 20 minutes to about 15 hours, or about 5 hours to about 10 hours, including values ​​at both ends). For example, the cast aluminum alloy may be heated at a temperature of about 400°C to about 600°C for about 20 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours, about 12 hours, about 13 hours, about 14 hours, about 15 hours, or any time in between. In some embodiments, the homogenization step includes heating the cast aluminum alloy product in a furnace for up to 60 hours. In some embodiments, the homogenization step includes heating the cast aluminum alloy product to a temperature of 540°C and immersing the cast aluminum alloy product for about 2 hours to produce a homogenized cast aluminum alloy product.

[0040] In some cases, the heating rate may be approximately 100°C / hour or less, 75°C / hour or less, 50°C / hour or less, 40°C / hour or less, 30°C / hour or less, 25°C / hour or less, 20°C / hour or less, or 15°C / hour or less. In other cases, the heating rate may be approximately 10°C / minute to approximately 100°C / minute (for example, approximately 10°C / minute to approximately 90°C / minute, approximately 10°C / minute to approximately 70°C / minute, approximately 10°C / minute to approximately 60°C / minute, approximately 20°C / minute to approximately 90°C / minute, approximately 30°C / minute to approximately 80°C / minute, approximately 40°C / minute to approximately 70°C / minute, or approximately 50°C / minute to approximately 60°C / minute).

[0041] Next, the cast aluminum alloy product is immersed (i.e., held at the indicated temperature) for a predetermined period. According to one non-limiting example, the cast aluminum alloy product is immersed for a maximum of about 15 hours (e.g., about 20 minutes to about 15 hours or about 5 hours to about 10 hours (including both values)). For example, the cast aluminum alloy can be immersed at a temperature of about 540°C to about 600°C for about 20 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, about 8 hours, about 9 hours, about 10 hours, about 11 hours, about 12 hours, about 13 hours, about 14 hours, about 15 hours, or any time in between.

[0042] Hot rolling A hot rolling process may be carried out following the homogenization process. The hot rolling process may include hot inversion milling and / or hot tandem milling. In some cases, the cast aluminum alloy product is laid down and hot-rolled at a hot rolling temperature of 250°C to 560°C (e.g., 300°C to 400°C, 350°C to 500°C, 510°C to 550°C, or 520°C to 540°C). For example, the hot rolling process can be carried out at temperatures of approximately 250°C, 260°C, 270°C, 280°C, 290°C, 300°C, 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C, 440°C, 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 505°C, 510°C, 515°C, 520°C, 525°C, 530°C, 535°C, 540°C, 545°C, 550°C, 555°C, and 560°C. In certain cases, the hot-rolling exit temperature may be in the range of approximately 200°C to approximately 290°C (for example, approximately 210°C to approximately 280°C or approximately 220°C to approximately 270°C). For example, the hot-rolling exit temperature may be approximately 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, 230°C, 235°C, 240°C, 245°C, 250°C, 255°C, 260°C, 265°C, 270°C, 275°C, 280°C, 285°C, 290°C, or any temperature in between.

[0043] In some cases, cast aluminum alloy products are hot-rolled from transfer bar gauge to hot band gauge to form hot-rolled products. Cast aluminum alloy products can enter the hot-rolling process with transfer bar gauges of 20mm to 50mm (e.g., 20mm to 35mm, 30mm to 40mm, or 35mm to 50mm). For example, cast aluminum alloy products may have transfer bar gauges of 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, or 50mm. During the hot rolling process, cast aluminum alloy products can be hot-rolled from a transfer bar gauge to a hot band gauge of 0.5 mm to 3.5 mm (for example, 1.0 mm to 2.5 mm, 0.5 mm to 1.5 mm, or 2.0 mm to 3.0 mm gauge), which are called hot-rolled products. For example, cast aluminum alloy products can be hot-rolled to produce hot-rolled products having hot band gauges of 3.5 mm, 3.4 mm, 3.3 mm, 3.2 mm, 3.1 mm, 3.0 mm, 2.9 mm, 2.8 mm, 2.7 mm, 2.6 mm, 2.5 mm, 2.4 mm, 2.3 mm, 2.2 mm, 2.1 mm, 2.0 mm, 1.9 mm, 1.8 mm, 1.7 mm, 1.6 mm, 1.5 mm, 1.4 mm, 1.3 mm, 1.2 mm, 1.1 mm, 1.0 mm, 0.9 mm, 0.8 mm, 0.7 mm, 0.6 mm, or 0.5 mm.

[0044] In some examples, a hot rolling process may include multiple hot rolling passes to reduce the thickness to a hot band gauge. In some embodiments, a hot rolling process may include 21 or fewer passes (e.g., fewer than 20 passes, fewer than 15 passes, fewer than 10 passes, or fewer than 5 passes) to produce a hot-rolled product with a hot band gauge of 0.5 mm to 3.5 mm. For example, a hot rolling process may use 21 passes, 20 passes, 19 passes, 18 passes, 17 passes, 16 passes, 15 passes, 14 passes, 13 passes, 12 passes, 11 passes, 10 passes, 9 passes, 8 passes, 7 passes, 6 passes, 5 passes, 4 passes, 3 passes, 2 passes, or 1 pass to produce a hot-rolled product with a hot band gauge of 0.5 mm to 3.5 mm.

[0045] Solution heat treatment In some examples, the solution heat treatment process can be carried out on hot-rolled products, cold-rolled products, or both. In some embodiments, hot-rolled products may enter the solution heat treatment process with an input gauge thickness in the range of 0.5 mm to 3.5 mm (e.g., 0.8 mm to 2.5 mm). The solution heat treatment process may involve heating the hot-rolled or cold-rolled product from room temperature (e.g., ambient temperature) to the peak metal temperature. For example, the hot-rolled product may be cooled to ambient temperature before the solution heat treatment process. In some cases, the peak metal temperature may be called the solution heat treatment temperature. Optionally, the peak metal temperature may be about 450°C to about 580°C (e.g., about 460°C to about 570°C, about 470°C to about 560°C, about 520°C to about 530°C, about 515°C to about 520°C, or about 515°C to about 545°C). For example, the peak metal temperature may be 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, or any temperature in between. Hot-rolled or cold-rolled products can be immersed at the peak metal temperature for a certain period of time. In certain embodiments, hot-rolled or cold-rolled products may be immersed at the solution heat treatment temperature for up to 50 seconds (e.g., from about 1 second to about 50 seconds, including values ​​at both ends). For example, hot-rolled or cold-rolled products may be immersed in a temperature of approximately 450°C to approximately 580°C for 1 second, 2 seconds, 3 seconds, 4 seconds, 5 seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, 10 seconds, 11 seconds, 12 seconds, 13 seconds, 14 seconds, 15 seconds, 16 seconds, 17 seconds, 18 seconds, 19 seconds, 20 seconds, 21 seconds, 22 seconds, 23 seconds, 24 seconds, 25 seconds, 26 seconds, 27 seconds, 28 seconds, 29 seconds, 30 seconds, 31 seconds, 32 seconds, 33 seconds, 34 seconds, 35 seconds, 36 seconds, 37 seconds, 38 seconds, 39 seconds, 40 seconds, 41 seconds, 42 seconds, 43 seconds, 44 seconds, 45 seconds, 46 seconds, 47 seconds, 48 ​​seconds, 49 seconds, 50 seconds, or any time in between. The solution heat treatment step may include heating the hot-rolled product at the solution heat treatment temperature for up to 50 seconds prior to the cold rolling step. The line speed for the solution heat treatment step may be at least 20 meters / minute (e.g., at least 10 meters / minute, 20-30 meters / minute, 20-40 meters / minute, etc.).

[0046] In some embodiments, the hot-rolled product is not subjected to solution heat treatment after hot rolling. For example, the hot-rolled product may be cooled and coiled (details below), and then cold-rolled to the final gauge thickness. In some embodiments, the hot-rolled product is supplied directly to the cold-rolling process.

[0047] In some embodiments, the hot-rolled product is coiled after hot rolling. During coiling, the hot-rolled product can be heat-treated with residual heat from the hot-rolling process. In some embodiments, the hot-rolled product is coiled at or near the hot-rolling outlet temperature. For example, the temperature of the hot-rolled product can be maintained at the hot-rolling outlet temperature during coiling. In other embodiments, coiling of the hot-rolled product is started at the hot-rolling outlet temperature, and the hot-rolled product cools to the cold-rolling temperature.

[0048] In some cases, cold-rolled products undergo solution heat treatment. For example, cold-rolled products may undergo solution heat treatment during at least two cold-rolling passes (e.g., two, three, four, or five cold-rolling passes). In non-limiting examples, cold-rolled products may undergo solution heat treatment during or after the cold-rolling process.

[0049] cold rolling A solution heat treatment process is followed by a cold rolling process to produce aluminum alloy products of the final gauge. In some cases, hot-rolled products are cooled to room temperature (e.g., near ambient temperature) before the cold rolling process. The inlet temperature for hot-rolled products to the cold rolling process may be in the range of 20°C to 80°C. In some examples, the cold rolling process is carried out in a cold rolling mill with one stand. In alternative examples, the cold rolling process is carried out in a tandem cold rolling mill with at least two stands arranged in series (e.g., at least three, at least four, at least five, or at least six stands arranged in series). In some cases, the cold rolling process is a two-stage process combining a single-stand cold rolling mill and a tandem cold rolling mill. For example, a two-stage cold rolling process may include a first cold rolling process using a tandem cold rolling mill and a second cold rolling process using a single-stand cold rolling mill. Alternatively, a two-stage cold rolling process may include a first cold rolling process using a single-stand cold rolling mill and a second cold rolling process using a tandem cold rolling mill.

[0050] In certain embodiments, a hot-rolled product can be cold-rolled in a cold-rolling process to obtain an aluminum alloy product of a final gauge thickness, i.e., a final gauge product. For example, a hot-rolled product that has undergone solution heat treatment can be cold-rolled to obtain an aluminum alloy product of a final gauge. In some examples, the cold-rolling process may include multiple cold-rolling passes to reduce the thickness to the final gauge thickness. In some embodiments, the cold-rolling process may include six or fewer passes (e.g., fewer than six passes, fewer than five passes, fewer than four passes, fewer than three passes, or one pass) to produce a cold-rolled product of a final gauge. In certain embodiments, the passes in the cold-rolling process may be referred to as reductions (e.g., thickness reductions). For example, the cold-rolling process may produce a cold-rolled product of a final gauge by using three passes to reduce the thickness of a hot-rolled product from 3.0 mm to a final gauge thickness of less than 0.30 mm. Cold-rolled products can be rolled to a final gauge thickness of 0.180mm to 0.250mm (e.g., 0.190mm to 0.250mm). Compared to conventional AA5182 aluminum alloy, the cold rolling process for producing cold-rolled products of 6xxx series aluminum alloys to their final gauge can use fewer passes because 6xxx series aluminum alloys are softer than conventional AA5182 aluminum alloys. This reduction in the number of passes in the cold rolling process shortens the time spent, saves resources to improve carbon efficiency, and thereby reduces the manufacturing costs and environmental impact associated with producing aluminum alloy products to their final gauge.

[0051] In some cases, the cold rolling process reduces the thickness of a hot-rolled product by at least 80% (e.g., at least 90%, at least 95%, or about 85% to about 95%) to the final gauge. For example, the cold rolling process reduces the thickness of a hot-rolled product by about 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, or about 95%. Cold-rolled products obtained from the cold rolling process exit at a cold-rolling exit temperature of about 150°C or higher (e.g., about 170°C to about 190°C, about 165°C to about 185°C, about 150°C to about 220°C, about 160°C to about 220°C, or about 170°C to about 220°C). For example, the cold-rolled exit temperature may be approximately 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, or 220°C. The cold-rolled product can be precipitation-hardened using the residual heat corresponding to the cold-rolled exit temperature.

[0052] In certain embodiments, a hot-rolled product (e.g., a hot-rolled product that has undergone solution heat treatment) is cold-rolled in a cold-rolling process to produce an aluminum alloy product of final gauge (e.g., a sheet or shade). In some examples, the final gauge aluminum alloy product has a thickness in the range of approximately 0.180 mm to 0.250 mm (e.g., approximately 0.180 mm to approximately 0.210 mm, or approximately 0.220 mm to approximately 0.250 mm). For example, the final gauge aluminum alloy product may have a thickness of 0.208 mm for use as can end material. In another example, the final gauge aluminum alloy product may have a thickness of 0.240 mm for use as can end material.

[0053] Coil cooling Optionally, cold-rolled products can be coiled when they leave the cold-rolling mill. In some examples, cold-rolled products are coiled when they leave the cold-rolling mill to become cold-rolled coils. Cold-rolled coils may be called coiled aluminum alloy products. In some further examples, cold-rolled coils are cooled, for example, by air cooling. The cooling process can be carried out at a rate of about 5°C / hour (°C / h) to about 500°C / h. For example, the coil cooling process can be carried out at a rate of about 5°C / h, 10°C / h, 15°C / h, 20°C / h, 25°C / h, 50°C / h, 100°C / h, 200°C / h, 300°C / h, 400°C / h, 500°C / h, or any rate in between. In some further examples, the cooled coils are stored for a certain period of time. In some cases, cold-rolled coils are aged by maintaining them at a temperature of approximately 150°C to 250°C (e.g., approximately 150°C to 200°C, or approximately 150°C to 250°C). Cold-rolled coils can be aged for 1 to 10 hours, such as 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, or any time in between. In alternative examples, the cooling coils are stored at room temperature for a certain period of time. Cold-rolled coils may undergo precipitation hardening as they cool from the cold-rolling exit temperature. Instead of providing an additional step of heating the cold-rolled coils in an oven or furnace, the cold-rolled coils can rely on residual heat from the cold-rolling process for precipitation hardening. In some cases, precipitation hardening may correspond to an optional artificial aging of the cold-rolled coils.

[0054] Optional intermediate annealing In some non-limiting examples, an optional intermediate annealing step can be performed during a two-stage cold rolling process. For example, a hot-rolled product can be cold-rolled to a first cold-rolled product (first cold rolling step), and optionally, coiled, annealed, and then cold-rolled to an aluminum alloy product of the final gauge (second cold rolling step). In some embodiments, the optional intermediate annealing can be performed in a batch process (i.e., a batch intermediate annealing step) or a continuous process. The intermediate annealing process can be carried out at temperatures ranging from approximately 300°C to approximately 450°C (for example, approximately 310°C, 320°C, 330°C, 340°C, 350°C, 360°C, 370°C, 380°C, 390°C, 400°C, 410°C, 420°C, 430°C, 440°C, or 450°C).

[0055] In some cases, the heating rate in the intermediate annealing process may be approximately 100°C / hour or less, 75°C / hour or less, 50°C / hour or less, 40°C / hour or less, 30°C / hour or less, 25°C / hour or less, 20°C / hour or less, or 15°C / hour or less. In other cases, the heating rate may be approximately 10°C / min to approximately 100°C / min (for example, approximately 10°C / min to approximately 90°C / min, approximately 10°C / min to approximately 70°C / min, approximately 10°C / min to approximately 60°C / min, approximately 20°C / min to approximately 90°C / min, approximately 30°C / min to approximately 80°C / min, approximately 40°C / min to approximately 70°C / min, or approximately 50°C / min to approximately 60°C / min).

[0056] In some embodiments, the first cold-rolled product is immersed for a certain period of time during the intermediate annealing process. According to one non-limiting example, the first cold-rolled product is immersed for a maximum of about 5 hours (e.g., about 30 minutes to about 4 hours, about 45 minutes to about 3 hours, or about 1 hour to about 2 hours, including values ​​at both ends). For example, the first cold-rolled product can be immersed at a temperature of about 300°C to about 450°C for about 20 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, about 2 hours, about 3 hours, about 4 hours, about 5 hours, or any time in between.

[0057] Optionally, the first cold-rolled product may be cooled, for example, by air cooling, after the intermediate annealing process. The cooling process can be carried out at a rate of approximately 5°C / hour (°C / h) to 20°C / h (e.g., 6°C / h to 18°C / h, 8°C / h to 15°C / h, or 10°C / h to 14°C / h). For example, the coil cooling process can be carried out at a rate of approximately 5°C / h, 6°C / h, 7°C / h, 8°C / h, 9°C / h, 10°C / h, 11°C / h, 12°C / h, 13°C / h, 14°C / h, 15°C / h, 16°C / h, 17°C / h, 18°C / h, 19°C / h, 20°C / h, or any rate in between. In some examples, the cooled coil is cooled to room temperature. In some further examples, the cooled coil is stored for a certain period of time.

[0058] In some embodiments, the method does not involve artificial aging of the cold-rolled product. For example, the cold-rolled product may have sufficient strength and formability.

[0059] Aluminum alloy composition The properties of an aluminum alloy are determined in part by its composition. In certain embodiments, the alloy composition can influence, or even determine, whether the alloy has properties suitable for a desired application, such as formability and deep drawability. Among the many properties, the aluminum alloys described herein exhibit particularly excellent ductility and formability.

[0060] In some embodiments, the method described herein can be used to manufacture 6xxx series aluminum alloys for can end material. In additional or alternative embodiments, the method described herein can be used to manufacture 6xxx series aluminum alloys for can tab material for manufacturing tabs, or for can body material for manufacturing can bodies. Exemplary examples of 6xxx series aluminum alloys used in the method described herein are AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, AA6205, AA6305, AA6006, AA6106, AA6206, AA6306, A A6008, AA6009, AA6010, AA6110, AA6110A, AA6011, AA6111, AA6012, AA6012A, AA6013, AA6113, AA6014, AA6015, AA6 016, AA6016A, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA6027, AA6028, AA6031, AA6032, AA6033, AA6040, AA6041, AA6042, AA6043, AA6151, AA6351, AA6351A, AA6451, AA6951, AA6053, AA6 055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A, AA626 1. May include AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, AA6963, AA6064, AA6064A, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091, or AA6092.

[0061] In some cases, the aluminum alloys described herein may have the following elemental compositions as shown in Table 1. [Table 1]

[0062] In some cases, the aluminum alloys described herein may have the following elemental compositions, as shown in Table 2. [Table 2]

[0063] Silicon (Si) In some examples, alloys contain 0.40% to 1.40% (e.g., 0.50% to 1.30%, 0.60% to 1.20%, or 0.70% to 1.10%) of silicon (Si) based on the total weight of the alloy. For example, alloys may contain 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%. %, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.80%, 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.90 %, 0.91%, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, 1.00%, 1.01%, 1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%, 1.09%, 1.10%, 1.11%, 1.12%, 1.13%, 1.14%, 1.15%, 1.16 It may contain Si in the following proportions: 1.17%, 1.18%, 1.19%, 1.20%, 1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%, 1.29%, 1.30%, 1.31%, 1.32%, 1.33%, 1.34%, 1.35%, 1.36%, 1.37%, 1.38%, 1.39%, or 1.40%. All percentages are expressed in wt.%.

[0064] Iron (Fe) In some examples, the alloy also contains an amount of iron (Fe) ranging from 0.20% to 0.80% (e.g., 0.20% to 0.70%, 0.30% to 0.80%, 0.30% to 0.60%, or 0.40% to 0.50%) based on the total weight of the alloy. For example, alloys are 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50% It may contain %, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, or 0.80% Fe. All percentages are expressed in wt.%.

[0065] Copper (Cu) In some examples, the disclosed alloys contain copper (Cu) in amounts of 0.05% to 1.00% (e.g., 0.05% to 0.85%, 0.15% to 0.90%, 0.25% to 0.80%, 0.35% to 0.70%, or 0.45% to 0.60%) based on the total weight of the alloy. For example, the alloys may contain 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0. 28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, It may contain 0.78%, 0.79%, 0.80%, 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.90%, 0.91%, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, or 1.00% Cu. All percentages are expressed in wt.%.

[0066] Manganese (Mn) In some examples, an alloy may contain manganese (Mn) in amounts ranging from 0.05% to 0.80% (e.g., 0.15% to 0.70%, 0.25% to 0.60%, 0.35% to 0.50%, 0.50% to 0.75%, 0.20% to 0.80%, 0.30% to 0.70%, or 0.30% to 0.50%) based on the total weight of the alloy. For example, alloys are 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0 It may contain Mn of 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, or 0.80%. All percentages are expressed as wt.%.

[0067] Magnesium (Mg) In some examples, an alloy may contain magnesium (Mg) in amounts ranging from 0.50% to 1.10% (e.g., 0.60% to 1.00%, 0.70% to 0.90%, or 0.50% to 1.00%) based on the total weight of the alloy. For example, alloys are 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.80% The alloys may contain Mg in the following proportions: 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.90%, 0.91%, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, 1.00%, 1.01%, 1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%, 1.09%, or 1.10%. All percentages are expressed in wt.%. The Mg content for use in the alloys described herein is carefully controlled based on the desired properties of the resulting alloy. For example, Mg may adversely affect the reusability or recovery rate of the aluminum alloys described herein.

[0068] Zinc (Zn) In some examples, the alloy contains up to 0.20% (e.g., up to 0.05%, up to 0.10%, 0.15%, 0.001%–0.20%, or 0.005%–0.20%) of zinc (Zn) based on the total weight of the alloy. For example, an alloy may contain 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, or 0.20% Zn. In some cases, Zn may not be present in the alloy (i.e., 0%). All percentages are expressed in wt.%.

[0069] Chromium (Cr) In some examples, alloys contain up to 0.30% (e.g., up to 0.20%, up to 0.25%, up to 0.05%, 0.001%-0.25%, 0.005%-0.10%, or 0.01%-0.25%) of chromium (Cr) based on the total weight of the alloy. For example, alloys may contain 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, It may contain 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, or 0.30% Cr. In some cases, Cr is not present in the alloy (i.e., 0%). All percentages are expressed in wt.%.

[0070] Bismuth (Bi) In some examples, the alloy contains up to 0.60% of bismuth (Bi) based on the total weight of the alloy (e.g., up to 0.05%, up to 0.10%, up to 0.20%, up to 0.30%, up to 0.40%, up to 0.50%, 0.001% to 0.50%, 0.005% to 0.35%, or 0.01% to 0.40%). For example, alloys are found in concentrations of 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, and 0.25%. Contains Bi in the following proportions: 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, or 0.60%. In some cases, Bi is not present in the alloy (i.e., 0%). All percentages are expressed in wt.%.

[0071] Lead (Pb) In some examples, the alloy contains up to 0.60% of lead (Pb) based on the total weight of the alloy (e.g., up to 0.05%, up to 0.10%, up to 0.20%, up to 0.30%, up to 0.40%, up to 0.50%, 0.001% to 0.50%, 0.005% to 0.35%, or 0.01% to 0.40%). For example, alloys are 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, It may contain 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, or 0.60% Pb. In some cases, Pb is not present in the alloy (i.e., 0%). All percentages are expressed in wt.%.

[0072] Optionally, the alloy compositions may further contain other trace elements, which may be called impurities, in amounts of 0.15% or less, 0.14% or less, 0.13% or less, 0.12% or less, 0.11% or less, 0.10% or less, 0.09% or less, 0.08% or less, 0.07% or less, 0.06% or less, 0.05% or less, 0.04% or less, 0.03% or less, 0.02% or less, or 0.01% or less. These impurities may include, but are not limited to, Na, Ga, V, Ni, Sc, Ag, B, Zr, Li, Ti, Sn, Ca, Hf, Sr, or combinations thereof. Therefore, Na, Ga, V, Ni, Sc, Ag, B, Zr, Li, Ti, Sn, Ca, Hf, or Sr may be present in the alloy in amounts of 0.05%, 0.04%, 0.03%, 0.02%, or 0.01% or less. In certain embodiments, the sum of all impurities does not exceed 0.15% (e.g., 0.1%). All percentages are expressed in wt.%. In certain embodiments, the remaining percentage of the alloy is aluminum.

[0073] recycled content The 6xxx aluminum alloys described herein can exhibit desirable mechanical properties while allowing for a relatively large amount of recycled aluminum alloy material. As previously mentioned, AA5182 aluminum alloy contains a large amount of Mg, which reduces the reusability and recyclability of aluminum alloy products. AA5182 aluminum alloy requires a high Mg content to achieve the strength requirements necessary for thin-gauge can end materials used to manufacture can ends. This limits the use of recycled aluminum alloy material in the manufacture of AA5182 aluminum alloy. Advantageously, the 6xxx series aluminum alloys described herein, due to their lower Mg content, can be manufactured from a larger amount of recycled aluminum material than AA5182 aluminum alloy and achieve similar properties. Furthermore, the 6xxx series aluminum alloys described herein can reduce the carbon footprint and energy consumption associated with the manufacture of aluminum alloys by reducing the number of rolling passes, while lowering manufacturing and / or processing costs.

[0074] The influence of impurities and / or alloying elements on the mechanical properties of 6xxx series aluminum alloys is reduced by providing aluminum alloy compositions adjusted to compensate for impurities and specific methods for manufacturing aluminum alloys. The aluminum alloys described herein may contain at least 20 wt.% recycled content (e.g., recycled aluminum material). For example, an aluminum alloy may contain at least about 20 wt.%, at least about 25 wt.%, at least about 30 wt.%, at least about 35 wt.%, at least about 40 wt.%, at least about 45 wt.%, at least about 50 wt.%, at least about 55 wt.%, at least about 60 wt.%, at least about 65 wt.%, at least about 70 wt.%, at least about 75 wt.%, at least about 80 wt.%, at least about 85 wt.%, at least about 90 wt.%, or at least about 95 wt.% recycled content. This makes it possible to use larger quantities of cheaper, more impurity-rich recycled aluminum material (e.g., used beverage cans) to produce aluminum alloys that exhibit desirable properties. The aluminum alloy compositions described herein may include a larger amount of recycled aluminum alloy with little to no additional primary aluminum and a reduced amount of more expensive alloying elements (e.g., Mg).

[0075] In some embodiments, the aluminum alloy compositions described herein provide compositions suitable for utilizing used beverage can (UBC) scrap or other aluminum alloy containers as recycled materials. UBC scrap is often a mixture of various aluminum alloys (e.g., from different aluminum alloys used for the can body and can end) and may contain impurities such as rainwater, leftover beverages, organic matter (e.g., paint and laminate film), and other materials. UBC scrap typically contains a mixture of metals from various aluminum alloys, such as metals from the can body (e.g., AA3104, AA3004, or other 3xxx series aluminum alloys) and can end (e.g., AA5182 or other 5xxx series aluminum alloys). UBC scrap may be cut and paint or lacquer removed before being melted down for use as a liquid metal material in casting new metal products. In some embodiments, a larger volume of used beverage cans can be used to produce the 6xxx series aluminum alloys described herein compared to the AA5182 aluminum alloy, thereby reducing the amount of primary aluminum required, lowering the total cost, and maintaining equivalent or better rolling productivity.

[0076] Furthermore, the beverage can may include a can body containing a 3xxx series aluminum alloy and a can end containing the 6xxx series aluminum alloy described herein. The aforementioned beverage can using a 6xxx series aluminum alloy as the can end has a lower overall Mg content than conventional cans containing a 5xxx series aluminum alloy as the can end. Because the 6xxx series aluminum alloy has a low Mg content, it provides a beverage can (a mixture of 3xxx series and 6xxx series aluminum alloys) that has fusion chemical properties that facilitate processing when recycling the beverage can.

[0077] In some embodiments, at least one of the can body, can tab, or can end is manufactured from the 6xxx series aluminum alloy described herein. For example, a beverage can may include a can body, can tab, and can end comprising the 6xxx series aluminum alloy described herein. Thus, the 6xxx series aluminum alloy provides a uniform beverage can constructed using the same series of aluminum alloys, enabling an easier recycling process by improving the fusion chemistry and uniformity of the beverage can material. In some embodiments, the uniform beverage can improve the recyclability of UBC scrap by increasing the commonality of the aluminum alloy composition, thereby reducing the addition of primary aluminum. Therefore, the 6xxx series aluminum alloy described herein improves the overall lifecycle of beverage cans and has improved recyclability compared to conventional cans.

[0078] alloy properties In some examples, the aluminum alloy products described herein have a yield strength of about 150 MPa to about 425 MPa (e.g., about 200 MPa to about 300 MPa, about 180 MPa to about 320 MPa, about 150 MPa to about 250 MPa, about 250 MPa to about 350 MPa, about 200 MPa to about 400 MPa, or about 300 MPa to about 425 MPa). For example, aluminum alloy products have pressures of approximately 150 MPa, 155 MPa, 160 MPa, 165 MPa, 170 MPa, 175 MPa, 180 MPa, 185 MPa, 190 MPa, 195 MPa, 200 MPa, 205 MPa, 210 MPa, 215 MPa, 220 MPa, 225 MPa, 230 MPa, 235 MPa, 240 MPa, 245 MPa, 250 MPa, 255 MPa, 260 MPa, 265 MPa, 270 MPa, 275 MPa, 280 MPa, and 2 The yield strength may be 85 MPa, approximately 295 MPa, approximately 300 MPa, approximately 305 MPa, approximately 310 MPa, approximately 315 MPa, approximately 320 MPa, approximately 325 MPa, approximately 330 MPa, approximately 335 MPa, approximately 340 MPa, approximately 345 MPa, approximately 350 MPa, approximately 355 MPa, approximately 360 MPa, approximately 365 MPa, approximately 370 MPa, approximately 375 MPa, approximately 380 MPa, approximately 385 MPa, approximately 390 MPa, approximately 395 MPa, approximately 400 MPa, approximately 405 MPa, approximately 410 MPa, approximately 415 MPa, approximately 420 MPa, or approximately 425 MPa. The aluminum alloy products described herein may exhibit yield strengths as described herein when measured in the longitudinal (L), transverse (T), and / or diagonal (D) directions with respect to the rolling direction, respectively.

[0079] In some examples, the aluminum alloy products described herein have a maximum tensile strength of about 300 MPa to about 450 MPa (e.g., about 325 MPa to about 450 MPa, about 350 MPa to about 450 MPa, about 375 MPa to about 450 MPa, or about 400 MPa to about 450 MPa). For example, aluminum alloy products may have a maximum tensile strength of about 300 MPa, about 310 MPa, about 320 MPa, about 330 MPa, about 340 MPa, about 350 MPa, about 360 MPa, about 370 MPa, about 380 MPa, about 390 MPa, about 400 MPa, about 410 MPa, about 420 MPa, about 430 MPa, about 440 MPa, or about 450 MPa. The aluminum alloy products described herein may exhibit the maximum tensile strength as described herein when measured in the longitudinal (L), transverse (T), and / or diagonal (D) directions with respect to the rolling direction, respectively.

[0080] In some cases, the aluminum alloy products described herein may have an elongation of about 1% to about 20% (e.g., about 1% to about 10%, about 5% to about 15%, about 5% to about 15%, or about 10% to about 20%). For example, the aluminum alloy products may have an elongation of about 3%, about 4%, 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, or any value in between. The aluminum alloy products described herein may exhibit the elongation described herein when measured in the longitudinal (L), transverse (T), and / or diagonal (D) directions with respect to the rolling direction, respectively.

[0081] In some cases, the aluminum alloy products described herein exhibit good surface finish quality (e.g., brightness and / or gloss). For example, the aluminum alloy products described herein have a higher post-rolling gloss value (e.g., spectral reflectance) than conventional AA5182 aluminum alloy, indicating that the aluminum alloy products exhibit a high degree of shine or brightness when reflecting light from a light source. The gloss value of an aluminum alloy product can indicate product quality or contribute to the customer's impression of the aluminum alloy product. Therefore, in some cases, customers may prefer the aluminum alloy products described herein to AA5182 aluminum alloy for at least partly reasons that the aluminum alloy product has a higher gloss value.

[0082] How to use The aluminum alloy products described herein (e.g., the final gauge aluminum alloy products) can be used for beverage can applications and other container applications. For example, the disclosed aluminum alloy products can be used in the manufacture of parts of beverage or food containers. In some examples, the disclosed aluminum alloy products can be used to manufacture can ends, can bodies, tabs, or lids used in beverage or food containers. In some examples, the aluminum alloy products can be used to manufacture can ends. In some examples, the aluminum alloy products can be used to manufacture can tabs. In some examples, the aluminum alloy products can be used to manufacture can bodies.

[0083] The examples disclosed herein are helpful in further illustrating aspects of the invention, but at the same time do not constitute any limitation thereof. Rather, it should be clearly understood after reading the description herein that various embodiments, modifications thereof, and equivalents may be used, which may be suggested to those skilled in the art without departing from the spirit of the invention. In addition, unless otherwise stated, the examples and embodiments described herein may also utilize prior procedures. Some procedures are described herein for illustrative purposes.

[0084] Examples Example 1: A method for manufacturing an aluminum alloy product, comprising casting an aluminum alloy to manufacture a cast aluminum alloy product, wherein the aluminum alloy includes a 6xxx series aluminum alloy, casting the aluminum alloy, homogenizing the cast aluminum alloy product to manufacture a homogenized cast aluminum alloy product, hot rolling the homogenized cast aluminum alloy product to manufacture a hot-rolled product, and optionally, i) the hot-rolled product at approximately 450°C The method comprising: ii) performing a solution heat treatment at a solution heat treatment temperature of ~600°C; or ii) forming the hot-rolled product into a coil at the hot-rolling outlet temperature; and cold-rolling the hot-rolled product to manufacture a cold-rolled product, wherein the cold-rolled product is rolled to a final gauge thickness of 0.180 mm to 0.250 mm, and the outlet temperature of the cold-rolled product is 150°C or higher; and optionally performing a solution heat treatment on the cold-rolled product at a solution heat treatment temperature of approximately 450°C to 580°C.

[0085] Example 2: The method of any of the preceding or following examples, further comprising coiling the cold-rolled product for the purpose of manufacturing a coiled aluminum alloy product, wherein the cold-rolled product is configured to undergo precipitation hardening during coil cooling.

[0086] Example 3: The method according to any of the preceding or succeeding examples, further comprising coating the coiled aluminum alloy product.

[0087] Example 4: The casting process is the method described in any of the preceding or subsequent examples, including direct chill casting.

[0088] Example 5: The method according to any of the preceding or following examples, wherein the aluminum alloy product comprises 0.20 to 1.40 wt.% Si, 0.20 to 0.80 wt.% Fe, 0.05 to 1.00 wt.% Cu, 0.05 to 0.80 wt.% Mn, 0.50 to 1.60 wt.% Mg, up to 0.25 wt.% Zn, up to 0.30 wt.% Cr, up to 0.60 wt.% Bi, up to 0.60 wt.% Pb, up to 0.15 wt.% impurities, and the remainder Al.

[0089] Example 6: The method according to any of the preceding or succeeding examples, wherein the homogenization step is carried out at a homogenization temperature of approximately 540°C to 600°C.

[0090] Example 7: The method according to any of the preceding or succeeding examples, wherein the hot-rolled product is cooled to approximately ambient temperature before the solution heat treatment step.

[0091] Example 8: The method according to any of the preceding or following examples, wherein the solution heat treatment step includes heating the hot-rolled product at the solution heat treatment temperature for up to 50 seconds prior to the cold rolling step.

[0092] Example 9: The method according to any of the preceding or following examples, wherein the line speed of the solution heat treatment process is at least 20 meters / minute.

[0093] Example 10: The method according to any of the preceding or succeeding examples, wherein the inlet temperature of the hot-rolled product to the cold-rolling process is 20°C to 80°C.

[0094] Example 11: The method according to any of the preceding or succeeding examples, wherein the cold rolling process comprises six or fewer cold rolling passes to produce the cold-rolled product.

[0095] Example 12: The method according to any of the preceding or succeeding examples, wherein the method does not include artificial aging after the cold rolling step.

[0096] Example 13: The method according to any of the preceding or following examples, wherein the cold rolling process is carried out in a cold rolling mill including at least two stands arranged in series.

[0097] Example 14: The method according to any of the preceding or following examples, wherein the cold rolling process comprises one pass for producing the cold-rolled product.

[0098] Example 15: The method according to any of the preceding or following examples, wherein the outlet temperature of the cold-rolled product is 150°C to 220°C.

[0099] Example 16: The method according to any of the preceding or following examples, wherein the cold rolling process reduces the cold working thickness of the hot-rolled product by at least 80% compared to the cold-rolled product.

[0100] Example 17: The method according to any of the preceding or following examples, wherein the cold rolling process reduces the cold working thickness by approximately 85% to approximately 95%.

[0101] Example 18: The method according to any of the preceding or following examples, wherein the hot rolling process is configured to produce a hot-rolled product having a hot band gauge of approximately 0.5 mm to 3.5 mm.

[0102] Example 19: The method according to any of the preceding or succeeding examples, characterized in that the hot rolling process uses 21 or fewer passes to produce the hot-rolled product.

[0103] Example 20: The method according to any of the preceding or following examples, wherein precipitation hardening is configured to occur using residual heat corresponding to the exit temperature of the cold-rolled product.

[0104] Example 21: The method according to any of the preceding or succeeding examples, wherein the aluminum alloy product exhibits a yield strength of approximately 150 MPa to 425 MPa.

[0105] Example 22: The aluminum alloy product having an elongation of 1% to 20%, according to the method of any of the preceding or succeeding examples.

[0106] Example 23: The method according to any of the preceding or succeeding examples, further comprising solution heat treatment of the cold-rolled product.

[0107] Example 24: The method according to any of the preceding or following examples, wherein the cold rolling process comprises six or fewer cold rolling passes to produce the cold-rolled product, and the method further comprises solution heat treatment of the cold product between at least two cold rolling passes.

[0108] Example 25: The method according to any of the preceding or succeeding examples, further comprising aging the coiled aluminum alloy product at a temperature of 150°C to 250°C for 1 to 10 hours.

[0109] Example 26: An aluminum alloy can end material, wherein the aluminum alloy can end material includes an aluminum alloy product prepared by the method described in any of the preceding or subsequent embodiments.

[0110] Example 27: The aluminum alloy can end material described in any of the preceding or succeeding examples, wherein the aluminum alloy can end material comprises at least 20 wt.% recycled aluminum material.

[0111] Example 28: The recycled aluminum material is an aluminum alloy can end material as described in any of the preceding or following examples, including used beverage can scrap.

[0112] Example 29: The method according to any of the preceding or following examples, wherein forming the hot-rolled product into a coil at the hot-rolling outlet temperature includes maintaining the hot-rolled product at the hot-rolling outlet temperature while forming the coil, or forming the hot-rolled product into a coil at the hot-rolling outlet temperature when the hot-rolled product cools to the cold-rolling temperature.

[0113] Example 1 To determine the properties of the aluminum alloys described herein, aluminum alloy samples were tested. Comparative Example 1 was prepared from the conventional AA5182 aluminum alloy currently used as a can end material. Alloy 1 is a 6xxx series aluminum alloy described herein. Table 3 shows the aluminum alloy compositions of Comparative Example 1 and Alloy 1. In Table 3, all values ​​are expressed as weight percentages (wt.%) based on the total weight of the aluminum alloy composition. The alloy may contain up to 0.15 wt.% impurities in total. [Table 3]

[0114] Figure 1 is a schematic diagram showing method 100 for manufacturing alloy 1. Alloy 1 was directly chill-cast to obtain an ingot 110 with an initial thickness of 660 mm. The ingot 110 was subjected to the homogenization process as described above. Next, the ingot 110 was hot-rolled using fewer than 20 hot-rolling passes to obtain a hot-rolled product with a thickness of 2.1 mm. The hot-rolled product was further subjected to solution heat treatment before cold-rolling in a cold mill to obtain a final gauge aluminum alloy product. In the solution heat treatment process, the hot-rolled product was continuously annealed and solution-treated at a peak metal temperature of approximately 515°C to 520°C. The solution-treated hot-rolled product was cold-rolled to the final gauge thickness using a tandem mill with three stands. The thickness of the hot-rolled product was reduced by 90%, from 2.1 mm to 0.208 mm, to produce an aluminum alloy product. After exiting the cold rolling process, the final gauge aluminum alloy product was formed into a coil, and precipitation hardening was performed in the coil cooling process.

[0115] Figure 2 is a bar graph showing the electrical conductivity of alloy 1 at the time of receipt and after the processing steps. The first two bars in Figure 2 show the electrical conductivity of alloy 1 at the time of receipt (after hot rolling). The third and ninth bars in Figure 2 show the electrical conductivity of alloy 1 after the solution heat treatment process at solution heat treatment temperatures of 540°C and 560°C, respectively. The fourth, fifth, and sixth bars in Figure 2 show the electrical conductivity of alloy 1 after the solution heat treatment process at 540°C, with cold work thickness reductions of 70%, 80%, and 90%, respectively. Similarly, the tenth, eleventh, and twelfth bars in Figure 2 show the electrical conductivity of alloy 1 after the solution heat treatment process at 560°C, with cold work thickness reductions of 70%, 80%, and 90%, respectively.

[0116] The seventh and eighth rods in Figure 2 show the conductivity of alloy 1 after a solution heat treatment process at 540°C, followed by coil cooling at temperatures of 160°C and 180°C, respectively. Figure 2 shows a significant increase in the conductivity of alloy 1 after coil cooling, indicating that precipitation occurs at these temperatures during coil cooling. Therefore, the increase in conductivity indicates that alloy 1 undergoes precipitation hardening during coil cooling, thereby eliminating the conventional heating process for precipitation hardening of aluminum alloys using a furnace or oven. Similar increases in conductivity are shown in the thirteenth and fourteenth rods in Figure 2, which show the conductivity of alloy 1 after a solution heat treatment process at 560°C, followed by coil cooling from 160°C and 180°C, respectively.

[0117] Figure 3 is a bar graph showing the yield strength, broadening, and elongation of test samples obtained from alloy 1 after various processing steps. Tensile properties were evaluated longitudinally with respect to the rolling direction during processing. Alloy 1 was processed using a solution heat treatment process at approximately 560°C. The first bar in Figure 3 corresponds to alloy 1 as received before the solution heat treatment process. The second, third, and fourth bars in Figure 3 show the yield strength, broadening, and elongation of alloy 1 after cold working thickness reduction of approximately 70%, 80%, and 90%, respectively. The fifth, sixth, and seventh bars in Figure 3 show the yield strength, broadening, and elongation of alloy 1 after cold working thickness reduction and coil cooling from 160°C.

[0118] Similarly, the 8th, 9th, and 10th bars in Figure 3 show the yield strength, broadening, and elongation of alloy 1 after cold working thickness reduction and coil cooling from 180°C. The mechanical properties of alloy 1 are closest to those of conventional AA5182 aluminum alloy used for can end material after cold working thickness reduction of approximately 80% and coil cooling from 180°C, corresponding to the 9th bar in Figure 3. Similar results were achieved using a solution heat treatment process at approximately 540°C, as shown in Figure 4. The 11th and 12th bars in Figure 3 show the yield strength, broadening, and elongation of alloy 1 with T4 and T6 tempers, respectively.

[0119] Example 2 To determine the properties of the aluminum alloys described herein, additional samples of aluminum alloys were tested. Comparative Example 1 (above) was prepared from the conventional AA5182 aluminum alloy currently used as a can end material. Example Alloy 2 is a 6xxx series aluminum alloy described herein. Table 4 shows the aluminum alloy composition of Example Alloy 2 with a maximum of 0.05 wt.% impurities and the remainder being Al. In Table 4, all values ​​are expressed as weight percentages (wt.%) based on the total weight of the aluminum alloy composition. [Table 4]

[0120] Alloy 2 of the example was manufactured according to the following method. An ingot was obtained by direct chill casting of the alloy. The ingot was subjected to the homogenization process as described above. Next, the ingot was hot-rolled to obtain a hot-rolled product with a thickness of 2.5 mm. The hot-rolled product was further subjected to solution heat treatment before cold rolling in a cold mill to obtain a final gauge aluminum alloy product. In the solution heat treatment process, the hot-rolled product was continuously annealed at a peak metal temperature of approximately 500°C to 525°C to achieve solution treatment. The solution-treated hot-rolled product was cold-rolled to the final gauge thickness using a tandem mill with three stands. During cold rolling, the thickness of the hot band was reduced by 64% in the first pass, 64% in the second pass, and 36% in the third pass to produce an aluminum alloy product with a final thickness of 0.21 mm. After exiting the cold rolling process, the aluminum alloy product was formed into a coil and subjected to precipitation hardening in a coil cooling process. Coil cooling was carried out at a temperature of 180°C. Next, the aluminum alloy product was coated, lubricant was applied, and a can end for testing was manufactured.

[0121] Figure 5 shows a graph of the whiteness values ​​for Comparative Example 1 and Example Alloy 2. Figure 6 shows a graph of the gloss values ​​obtained at 60° for Comparative Example 1 and Example Alloy 2. The can end of Example Alloy 2, manufactured from 6xxx series aluminum alloy, had higher whiteness and gloss values ​​than Comparative Example 1. Specifically, Example Alloy 2 showed a 40% higher whiteness value than Comparative Example 1. Similarly, Example Alloy 2 had a 100% higher gloss value than Comparative Example 1. The data indicates that Example Alloy 2, when used as a can end, has superior visual and aesthetic properties compared to AA5182 alloy (Comparative Example 1).

[0122] Figure 7 shows graphs of the yield strength, maximum tensile strength, and elongation properties of Alloy 2 in examples after different processing conditions. The first three sets of bars represent the final gauge aluminum alloy products obtained in the rolling direction (L, 0°), transverse direction (T, 90°), and oblique direction (D, 45°) after solution heat treatment and cold rolling, and before being coiled. The fourth, fifth, sixth, and seventh sets of bars represent the final gauge aluminum alloy products obtained in the rolling direction (L, 0°) after the coils were cooled at 140°C, 150°C, 160°C, and 180°C, respectively. The eighth, ninth, and tenth sets of bars represent the final gauge aluminum alloy products obtained in the rolling direction (L, 0°), transverse direction (T, 90°), and oblique direction (D, 45°), respectively, after the coils were cooled at 180°C. The 11th, 12th, and 13th sets of rods represent the final gauge aluminum alloy products obtained in the rolling direction (L, 0°), transverse direction (T, 90°), and oblique direction (D, 45°), respectively, after coil cooling at 180°C and coating (using lubricant or lacquer in an oven for two cycles at 180°C to 300°C, respectively). As shown in Figure 4, alloy 2 of the example showed an increase in yield strength and maximum tensile strength when subjected to coil cooling. In fact, when the final gauge aluminum alloy products were subjected to coil cooling at a temperature of 140°C to 150°C, precipitation appeared to be dominant, and the best strength and elongation values ​​were obtained. Furthermore, in the simulated coating process, an increase in strength was measured after coating the can end.

[0123] Figure 8 shows the propagation energy (kJ / m) of alloy 2 in the example and comparative example 1, as measured by the Kahn tear test. 2 The graph shows the following. Can ends are typically coated with a corrosion-resistant finish that is durable even in high temperatures and ovens. Conventional coated AA5182 alloy for can end material is represented by the blue line in the graph, with a tolerance of approximately 42 kJ / m³. 2 It has a propagation energy of . Alloy 2 of the example was coated in an oven for two cycles at temperatures of 180°C and 300°C, respectively. Alloy 2 of the example had a propagation energy of approximately 50 kJ / m before coating. 2It shows a propagation energy of approximately 58 kJ / m after coating. 2 The propagation energy was shown. The propagation energy of alloy 2 in the example was higher than that of the coated AA5182 alloy, indicating the good fracture toughness of alloy 2 in the example.

[0124] Figure 9 shows graphs of the buckling strength (psi) of the shells of Example Alloy 2 and Comparative Example 1, measured using a calibrated commercially available shell / end pressure bulquar tester, Altek Model 9009. The graphs show the maximum buckling strength, the average buckling strength of 12 samples, and the minimum buckling strength. Example Alloy 2 showed higher maximum and average buckling strengths than Comparative Example 1.

[0125] Figure 10 shows graphs of the fresh buckling strength (psi) of Example Alloy 2 and Comparative Example 1, measured using a calibrated commercially available shell / end pressure bulquar tester, Altek Model 9009. Fresh buckling strength was tested before aging of the samples. The graphs show the maximum buckling strength, the average buckling strength of 12 samples, and the minimum buckling strength. Example Alloy 2 showed higher maximum and average buckling strengths than Comparative Example 1.

[0126] Figure 11 shows graphs of the turbo-aged buckling strength (psi) of Example Alloy 2 and Comparative Example 1, measured using a calibrated commercially available shell / end pressure bulquar tester, Altek Model 9009. The graphs show the maximum buckling strength, the average buckling strength of 12 samples, and the minimum buckling strength. Example Alloy 2 and Comparative Alloy (AA5182 alloy) were turbo-aged at 90°C for 30 minutes. Example Alloy 2 showed higher maximum and average buckling strengths than Comparative Alloy.

[0127] Figure 12 shows a graph of the results of shell clamping pressure forming under the most extreme test conditions when the sheets of alloy 2 in Example and comparative example 1 were formed with an internal sleeve pressure of 220 psi and an upper piston pressure of 165 psi. The tests were performed by adjusting the internal sleeve pressure and upper piston pressure using a specially developed shell manufacturing press. As shown in Figure 12, the 6xxx alloy of Example 2 showed better clamping formability at the can end than comparative example 1.

[0128] All patents, publications, and abstracts cited above are incorporated herein by reference in their entirety. Various embodiments of the present invention are described in relation to the achievement of various objectives of the present invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations thereof, which do not depart from the spirit and scope of the present invention as defined in the following claims, will be obvious to those skilled in the art.

Claims

1. A method for manufacturing aluminum alloy products, Casting an aluminum alloy to manufacture a cast aluminum alloy product, wherein the aluminum alloy includes a 6xxx series aluminum alloy, Homogenizing the cast aluminum alloy product in order to manufacture the homogenized cast aluminum alloy product, Hot rolling the homogenized cast aluminum alloy product in order to manufacture a hot-rolled product, Optionally, i) solution heat treatment the hot-rolled product at a solution heat treatment temperature of approximately 450°C to 600°C, or ii) coil the hot-rolled product at the hot-rolling outlet temperature. Cold rolling of a hot-rolled product in order to manufacture a cold-rolled product, wherein the cold-rolled product is rolled to a final gauge thickness of 0.180 mm to 0.250 mm, and the outlet temperature of the cold-rolled product is 150°C or higher, and Optionally, the cold-rolled product may be subjected to solution heat treatment at a solution heat treatment temperature of approximately 450°C to 580°C. The manufacturing method, including the above.

2. The method according to claim 1, further comprising coiling the cold-rolled product for the purpose of producing a coiled aluminum alloy product, wherein the cold-rolled product is configured to undergo precipitation hardening during and / or after coiling.

3. The method according to claim 2, further comprising coating the coiled aluminum alloy product.

4. The method according to claim 1, wherein the casting step includes direct chill casting.

5. The method according to claim 1, wherein forming the hot-rolled product into a coil at the hot-rolling outlet temperature includes maintaining the hot-rolled product at the hot-rolling outlet temperature while forming the coil, or initially forming the hot-rolled product into a coil at the hot-rolling outlet temperature when the hot-rolled product cools to the cold-rolling temperature.

6. The method according to claim 1, wherein the aluminum alloy product comprises 0.20 to 1.40 wt.% Si, 0.20 to 0.80 wt.% Fe, 0.05 to 1.00 wt.% Cu, 0.05 to 0.80 wt.% Mn, 0.50 to 1.60 wt.% Mg, up to 0.25 wt.% Zn, up to 0.30 wt.% Cr, up to 0.60 wt.% Bi, up to 0.60 wt.% Pb, up to 0.15 wt.% impurities, and the remainder Al.

7. The method according to claim 1, wherein the homogenization step is carried out at a homogenization temperature of approximately 540°C to 600°C.

8. The method according to claim 1, wherein the hot-rolled product is cooled to approximately ambient temperature before the solution heat treatment step.

9. The method according to claim 1, wherein the solution heat treatment step includes heating the hot-rolled product at the solution heat treatment temperature for a maximum of 50 seconds prior to the cold rolling step.

10. The method according to claim 9, wherein the line speed of the solution heat treatment step is at least 20 meters / minute.

11. The method according to claim 1, wherein the inlet temperature of the hot-rolled product to the cold-rolling process is 20°C to 80°C.

12. The method according to claim 1, wherein the cold rolling step includes six or fewer cold rolling passes for producing the cold-rolled product.

13. The method according to claim 1, wherein the method does not include artificial aging after the cold rolling step.

14. The method according to claim 12, wherein the cold rolling process is carried out in a cold rolling mill including at least two stands arranged in series.

15. The method according to claim 12, wherein the cold rolling step comprises one pass for producing the cold-rolled product.

16. The method according to claim 1, wherein the outlet temperature of the cold-rolled product is approximately 150°C to 220°C.

17. The method according to claim 1, wherein the cold rolling step results in a cold working thickness reduction of at least 80% from the hot-rolled product to the cold-rolled product.

18. The method according to claim 17, wherein the cold rolling process results in a cold working thickness reduction of approximately 85% to 95%.

19. The method according to claim 1, wherein the hot rolling step is configured to produce the hot-rolled product having a hot band gauge of about 0.5 mm to 3.5 mm.

20. The method according to claim 1, characterized in that the hot rolling process uses 21 or fewer passes to produce the hot-rolled product.

21. The method according to claim 1, wherein precipitation hardening is configured to occur using residual heat corresponding to the exit temperature of the cold-rolled product.

22. The method according to claim 1, wherein the aluminum alloy product has a yield strength of 150 MPa to 425 MPa.

23. The aluminum alloy product according to claim 1, wherein the aluminum alloy product has an elongation of 1% to 20%.

24. The method according to claim 1, further comprising solution heat treatment of the cold-rolled product.

25. The method according to claim 1, wherein the cold rolling step comprises six or fewer cold rolling passes for producing the cold-rolled product, and the method further comprises solution heat treatment of the cold-rolled product between at least two cold rolling passes.

26. The method according to claim 2, further comprising aging the coiled aluminum alloy product at a temperature of 150°C to 250°C for 1 to 10 hours.

27. An aluminum alloy can end material, wherein the aluminum alloy can end material includes an aluminum alloy product prepared by a method comprising any one of claims 1 to 26.

28. The aluminum alloy can end material according to claim 27, wherein the aluminum alloy can end material comprises at least 20 wt.% recycled aluminum material.

29. The aluminum alloy can end material according to claim 28, wherein the recycled aluminum material includes used beverage can scrap.

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