WO2025049886A1

WO2025049886A1 - High-strength aluminum alloys for food and beverage packaging and methods for preparing the same

Info

Publication number: WO2025049886A1
Application number: PCT/US2024/044640
Authority: WO
Inventors: Samuel RIBEIRO; Felipe PEREIRA; Hesron OLIVEIRA; YounGoo HWANG; Minhee Choi; DaeHoon KANG
Original assignee: Novelis Inc.
Priority date: 2023-08-30
Filing date: 2024-08-30
Publication date: 2025-03-06

Abstract

Described herein are novel aluminum alloys including recycled aluminum alloy materials which exhibit high strength and high formability. The aluminum alloys described herein are suitable for use in food and beverage packaging, such as in can body stock, and for example, exhibit high strength and formability while having a higher Mg content than conventional 3xxx series aluminum alloys used to produce such packaging, including can body stock. The present disclosure provides a cost-effective alternative to the use of AA3004 and AA3104, aluminum alloys for food and beverage packaging with comparable mechanical properties while incorporating higher amounts of recycled scrap.

Description

HIGH-STRENGTH ALUMINUM ALLOYS FOR FOOD AND BEVERAGE PACKAGING AND METHODS FOR PREPARING THE SAME

PRIORITY CLAIM

[0001] This application claims priority to U.S. Provisional Application No. 63/579,771, filed on August 30, 2023, the entire contents and disclosures of which are incorporated herein.

FIELD

[0002] The present disclosure relates to the fields of metallurgy, aluminum alloys, aluminum fabrication, and related fields. In particular, the present disclosure provides novel aluminum alloys having high amounts of recycled aluminum materials, which can be useful for producing food and beverage packaging, including can body stock.

BACKGROUND

[0003] Can body stock is conventionally made from high-strength aluminum alloys that have good formability properties. The mechanical requirements for aluminum alloys used to produce can body stock are different than the mechanical requirements for can end stock. In general, aluminum alloys for producing can body stock require less strength than can end stock. As a result, can body stock is often fabricated from an aluminum alloy comprising lower amounts of magnesium (Mg) than can end stock. For instance, can body stock may be fabricated from an AA3004 aluminum alloy that has a Mg content between 0.80 wt. % to 1.30 wt. %.

[0004] Many aluminum manufacturers use 3xxx series aluminum alloys (e.g., AA3004 or AA3104) for can body stock. However, recycled material, such as Used Beverage Cans (UBC), are not used to produce can end stock and can body stock because UBC contains two separate aluminum alloys having different aluminum alloy compositions. Specifically, can end stock is typically produced from AA5182 aluminum alloy, and can body stock is typically produced from AA3104 aluminum alloy. Due to the two dissimilar aluminum alloys in UBC, there is little commonality in the composition to make new aluminum alloys for can body stock and can end stock. Therefore, if UBC is used to produce new aluminum alloys, there is a need to add primary aluminum and additional alloying elements to adjust the composition to produce can end stock and can body stock. This addition of primary aluminum and/or additional alloying elements reduces the circularity of recycled aluminum alloy products for producing new aluminum alloys, which decreases the recycled content. Moreover, additional primary aluminum increases the carbon dioxide production and increases costs, leading to environmental harm and high costs.

SUMMARY

[0005] Covered embodiments of the present disclosure are defined by the claims, not this summary. This summary is a high-level overview of various aspects of the invention and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification, any or all drawings and each claim.

[0006] Described herein are aluminum alloys that provide a more cost-effective and recyclefriendly material, as compared to AA3004 and AA3104 alloys, for use as food and beverage packaging, including as can body stock. The aluminum alloy may comprise up to 0.70 wt. % Si, up to 0.80 wt. % Fe, up to 0.60 wt. % Cu, 0.80 - 1.50 wt. % Mn, 1.30 - 2.00 wt. % Mg, up to 0.60 wt. % Zn, up to 0.30 wt. % Cr, up to 0.10 wt. % Ti, up to 0.15 wt. % impurities, and Al, wherein the aluminum alloy comprises at least 60 wt. % of recycled aluminum scrap. In some aspects, the aluminum alloy comprises 0.20 - 0.40 wt. % Si, 0.40 - 0.60 wt. % Fe, 0.10 - 0.30 wt. % Cu, 0.80 - 1.00 wt. % Mn, 1.35 - 1.50 wt. % Mg, up to 0.25 wt. % Zn, up to 0.05 wt. % Cr, up to 0.05 wt. % Ti, up to 0.15 wt. % impurities, and Al. The aluminum alloy may comprise greater than 75 wt. % of recycled aluminum scrap. The aluminum alloy may comprise less than 15 wt. % of primary aluminum or less than 5 wt. % of primary aluminum. The aluminum alloy may exhibit a yield strength of at least 200 MPa, preferably from 200 to 350 MPa. The aluminum alloy may exhibit an ultimate tensile strength of at least 250 MPa, preferably from 250 to 450 MPa. The aluminum alloy may comprise up to 100 wt. % of recycled aluminum scrap. The recycled aluminum scrap may comprise used beverage can scrap. The used beverage can scrap may contain a mixture of recycled metal from can ends and can bodies.

[0007] In some aspects, an aluminum alloy product, such as can body stock, can end stock, can tab stock, and other food and beverage packnig, may comprise the aluminum alloys described herein.

[0008] In some aspects, an aluminum alloy product may be produced by: casting an aluminum alloy to form a cast product; homogenizing the cast product; hot rolling the cast product to produce a hot rolled product; cold rolling the hot rolled product to produce an aluminum alloy product; and optionally annealing the aluminum alloy product. The aluminum alloy may be as described herein. The casting step may comprise continuously casting the aluminum alloy to form the cast product. The casting step may comprise direct chill casting the aluminum alloy to form the cast product. The method may further comprise lacquering and curing the aluminum alloy product.

[0009] Further aspects, objects, and advantages will become apparent upon consideration of the detailed description and figures that follow.

BRIEF DESCRIPTION OF THE FIGURES

[0010] FIG. 1 provides a flowchart depicting a process for producing a high-strength, high recycled content aluminum alloy using UBC or other aluminum scrap according to certain aspects of the present disclosure.

[0011] FIG. 2 provides a flowchart depicting a process for treating a final gauge rolled aluminum product produced using a high-strength, high recycled content aluminum alloy prior to downstream processing for can body stock applications according to certain aspects of the present disclosure.

DETAILED DESCRIPTION

[0012] Described herein are novel aluminum alloys that exhibit high strength and formability for use in can body stock applications. The aluminum alloys described herein exhibit high strength and formability while having a higher Mg content than traditional AA3004 aluminum alloys and AA3104 aluminum alloys used to produce can body stock. The aluminum alloys described herein incorporate higher amounts of recycled aluminum materials and less primary aluminum, as compared to traditional aluminum alloys used to produce can body stock, and still maintain good mechanical properties for can body stock. For example, the aluminum alloys described herein may include at least 60% recycled aluminum alloy and less than 40% primary aluminum than traditional aluminum alloys used to produce can body stock, and still exhibit similar mechanical properties as conventional 3xxx series aluminum alloys used for can body stock. The aluminum alloy composition described throughout provides a cost-effective alternative to the use of AA3004 aluminum alloys and AA3104 aluminum alloys for can body stock.

[0013] In addition to the use of the novel aluminum alloys for can body stock applications, the high strength and formability of the alloys, in combination with their high Mg content, may be useful in other applications. Such applications include any food and beverage packing application, including can end stock, can tab stock, can body stock, food cans, food ends, and others. The novel aluminum alloys may even be used in non-food and beverage applications, so long as high strength and formability are desirable.

[0014] Without being bound by theory, the high formability may allow the aluminum alloy product to be subjected to more aggressive stretching and thinning operations, providing processing advantages. Additionally, by modifying the rolling process, such as by using high speed and high temperature in a cold mill, the tensile strength and yield strength/ultimate tensile strength spread may be improved. This typically corresponds to increased product formability. Furthermore, using an increased cold mill speed during rolling may promote cold mill recovery for the product.

[0015] Conventional 3xxx series aluminum alloys for producing can body stock can require a strictly controlled composition to meet the mechanical requirements (e.g., strength requirements) while still maintaining formability to produce complex geometries. This limits the amount of recycled aluminum material that can be used to produce AA5182 aluminum alloy. For example, AA3104 aluminum alloy cannot be produced from high amounts of used beverage cans because AA3104 aluminum alloy includes lower amounts of Mg compared to used beverage cans. Used beverage cans include a mixture of two different aluminum alloys for can body stock and can end stock. The aluminum alloy used for can end stock is typically AA5182 aluminum alloy and the aluminum alloy used for can body stock is typically AA3104 aluminum alloy. AA3104 aluminum alloy includes lower amounts of Mg and higher amounts of Fe, Si, Mn, and Cu compared to AA5182 aluminum alloy. Due to the discrepancy between the aluminum alloy composition of AA3104 aluminum alloy and AA5182 aluminum alloy, used beverage cans have an aluminum alloy composition between the compositions for AA3104 aluminum alloy and AA5182 aluminum alloy. Therefore, in order to produce can body stock from large amounts of recycled materials, such as used beverage cans, it requires accounting for the higher Mg content of recycled aluminum scrap (e.g., by adding primary aluminum) to produce AA3104 aluminum alloy, which significantly increases manufacturing costs and environmental costs. This limits the amount of the recycled aluminum materials that can be used to produce can body stock.

[0016] The novel aluminum alloy described herein can utilize higher amounts of recycled aluminum materials and achieve properties similar to or greater than those of AA3104 aluminum alloys. Specifically, the aluminum alloy described herein can tolerate higher amounts of Mg (e.g., from 1.30 wt. % to 1.50 wt. %) compared to conventional 3xxx aluminum alloys for can body stock applications and still achieve good strength and formability properties. This may be particularly advantageous in terms of the prime requirement to dilute Mg content from scrap metal to a target level. And particularly for can end stock and can tab stock applications, using a 3xxx series alloy instead of AA5182 allows for a greater range of main elements. Such element include Si, Fe, Cu, and Mn. And as a result, this usage may lead to a significantly reduce prime usage, corresponding to a significantly reduce carbon footprint.

[0017] Additionally, the aluminum alloys described herein may include higher amounts of Mg that can be compensated by the reduction of elements such as Mn and Cu to compensate for Mg solid solution hardening. The composition of the aluminum alloy described herein reduces the compositional gap between can body stock and can end stock to lower the amount of primary aluminum required. By reducing the compositional gap between aluminum alloys for can body stock and can end stock, more recycled aluminum alloy, such as used beverage cans, may be used to produce aluminum alloys for can body stock. For example, the aluminum alloy described herein can be produced from at least 60 wt. % of recycled scrap and less than 15 wt. % of primary aluminum.

[0018] In addition the sustainability improvements of the aluminum alloys described herein, the circularity may be improved. Circularity refers to a model of production and consumption that aims to reduce waste and optimize resource use through the entire production and consumption cycle. Here, because the aluminum alloys may be used in a variety of food and beverage applications, the carbon footprint of various production processes may be reduced. Further, the above advantages of recycled content, processing efficiencies, and sustainability of the process each contribute to the improved circularity, as compared to aluminum alloys with different compositions and manufacturing processes. [0019] Additionally, the aluminum alloy composition produces can body stock having similar properties to conventional AA3004 aluminum alloys or AA3104 aluminum alloys, allowing can manufacturers to produce the aluminum alloy with little to no changes to their existing methods. The aluminum alloy composition can maintain good can buckle strength with increased sheet strength while maintaining formability and tear off performance due to the high Mg content of the aluminum alloy. Conventional strengthening approaches (e.g., Mn addition, Cu addition, or hot band gauge increase) can have negative side effects (e.g., higher amounts of particles, formability loss, productivity loss, etc.). In contrast, Mg addition maintains particle amount and particle size and can increase ductility if controlled well. In some embodiments, higher amounts of used beverage cans may be used with the aluminum alloy described herein, thereby reducing the amount of primary aluminum needed and reducing the total cost and maintaining equivalent or better rolling productivity. In addition to the high strength that is largely obtained from the relatively increased Mg and Mn content, the high strength advantageously allows for increase lightweighting (downgauging potential).

[0020] The aforementioned aluminum alloy composition has processing advantages despite having high amounts of recycled aluminum alloy, which is a common problem for using high amounts of recycled aluminum alloy for new aluminum alloys. The aluminum alloys described herein can be reused to make other aluminum alloy products (e.g., can body stock). Beneficially, incorporating high amounts of Mg allows for closed-loop recycling of used beverage cans (UBC) produced from the aluminum alloy composition described herein. In this way, UBC scrap can be continually reused in a closed loop system to produce the aluminum alloys without major changes to the alloying elements. That is, the aluminum alloy products (e.g., UBC) made from the aluminum alloy composition described herein can be used to produce new aluminum alloys for can end stock or can body stock. Moreover, due to the careful tailoring and elemental control for the alloy design, the amount of Mg content in UBC scrap is similar to the aluminum alloy composition described herein. Surprisingly, the aluminum alloy may include up to 100 wt. % recycled aluminum scrap to produce can body stock from UBC. Yet another processing benefit is that while the strength naturally increases with Mg addition, cold mill exit temperature can increase without losing the strength. This indicates the acceleration of cold mill speed, which leads to the improved cold mill productivity. [0021] In some embodiments, the present disclosure relates to an aluminum alloy that has high Mg content and high recycled content and exhibits properties similar to AA3004 and AA3104 aluminum alloys. For example, the aluminum alloy may include a Mg content similar to or greater than AA3004 aluminum alloy and AA3104 aluminum alloy. The aluminum alloys can include high amounts of recycled material and achieve properties similar to AA3104 aluminum alloy. In some embodiments, the aluminum alloys described herein may include a Mg content from 1.30 wt. % to 2.00 wt. %. UBC scrap can be used almost entirely to produce the aluminum alloy, which eliminates the need of diluting the aluminum alloy with primary aluminum or adding alloying elements for hardening. In other words, the tailored aluminum alloys described herein can include higher amounts of UBC scrap and less primary aluminum and minimal or no additional alloying elements. Advantageously, the aluminum alloy may include a Cu, Mn, and Mg content to meet the strength requirements for can body stock. The aluminum alloys described herein may include higher amounts of the Mg compared to AA3104 aluminum alloy while meeting the minimum strength requirements for can body stock and may include a Mg content from 1.30 wt. % to 2.00 wt. % Mg. In some aspects, the can end stock may be formed from the alloys described herein while convention alloys, such as A5182, may be used to form the can body stock and can tab stock.

[0022] To maintain a high level of recycled content in the aluminum alloy compositions described herein, the aluminum alloy composition can be similar to AA3104 aluminum alloy while including decreased amounts of Cu and Mn. Therefore, other hardening alloying elements (e.g., Mn and Cu) may not need to be added to the aluminum alloy composition. This is beneficial because hardening alloying elements (e.g., Mn and Cu) do not oxidize during the remelting process, thereby affecting the recyclability of the can body aluminum alloy or UBC composition. By maintaining aluminum alloy compositions similar to AA3104 aluminum alloy, the re-melting process may be simplified, thereby reducing the need to change the aluminum alloy during fabrication. The aluminum alloy compositions described herein contain higher levels of recycled content and less primary aluminum while also demonstrating mechanical properties similar to current aluminum alloy compositions for can body stock (e.g., similar to AA3004 aluminum alloy or AA3104 aluminum alloy).

Definitions and Descriptions [0023] As used herein, the terms “invention,” “the invention,” “this invention” and “the present invention” are intended to refer broadly to all of the subject matter of this patent application and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the patent claims below.

[0024] In this description, reference is made to alloys identified by aluminum industry designations, such as “series” or “3xxx For an understanding of the number designation system most commonly used in naming and identifying aluminum and its alloys, see “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 published by The Aluminum Association.

[0025] As used herein, the meaning of “a,” “an,” or “the” includes singular and plural references unless the context clearly dictates otherwise.

[0026] As used herein, a plate generally has a thickness of greater than about 15 mm. For example, a plate may refer to an aluminum product having a thickness of greater than about 15 mm, greater than about 20 mm, greater than about 25 mm, greater than about 30 mm, greater than about 35 mm, greater than about 40 mm, greater than about 45 mm, greater than about 50 mm, or greater than about 100 mm.

[0027] As used herein, a shate (also referred to as a sheet plate) generally has a thickness of from about 4 mm to about 15 mm. For example, a shate 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.

[0028] As used herein, a sheet generally refers to an aluminum product having a thickness of less than about 4 mm (e.g., 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, a sheet may have a thickness of about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5, about 0.6 mm about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 1.1 mm, about 1.2 mm, about 1.3 mm, about 1.4 mm, about 1.5 mm, about 1.6 mm, about 1.7 mm, about 1.8 mm, about 1.9 mm, about 2 mm, about 2.1 mm, about 2.2 mm, about 2.3 mm, about 2.4 mm, about 2.5 mm, about 2.6 mm about 2.7 mm, about 2.8 mm, about 2.9 mm, about 3 mm, about 3.1 mm, about 3.2 mm, about 3.3 mm, about 3.4 mm, about 3.5 mm, about 3.6 mm, about 3.7 mm, about 3.8 mm, about 3.9 mm, or about 4 mm.

[0029] As used herein, formability refers to the ability of a material to undergo deformation into a desired shape without fracturing, tearing-off, necking, earing, or shaping errors such as wrinkling, spring-back, or galling occurring. In engineering, formability may be classified according to deformation modes. Examples of deformation modes include drawing, stretching, bending, and stretch-flanging.

[0030] As used herein, primary aluminum refers to an aluminum material including about at least 99.7 wt. % aluminum. Primary aluminum is produced from the prime transformation of raw material into aluminum (e.g., processing of bauxite into alumina and electrolysis of alumina into aluminum).

[0031] As used herein, yield stress (also referred to as yield strength) refers to the point at which an aluminum alloy begins to plastically deform and can no longer return to its original state.

[0032] Reference may be made in this application to alloy temper or condition. For an understanding of the alloy temper descriptions most commonly used, see “American National Standards (ANSI) H35 on Alloy and Temper Designation Systems.” An F condition or temper refers to an aluminum alloy as fabricated. An O condition or temper refers to an aluminum alloy after annealing. An Hxx condition or temper, also referred to herein as an H temper, refers to a non-heat treatable aluminum alloy after cold rolling with or without thermal treatment (e.g., annealing). Suitable H tempers include HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8, or HX9 tempers. A T1 condition or temper refers to an aluminum alloy cooled from hot working and naturally aged (e.g., at room temperature). A T2 condition or temper refers to an aluminum alloy cooled from hot working, cold worked and naturally aged. A T3 condition or temper refers to an aluminum alloy solution heat treated, cold worked, and naturally aged. A T4 condition or temper refers to an aluminum alloy solution heat treated and naturally aged. A T5 condition or temper refers to an aluminum alloy cooled from hot working and artificially aged (at elevated temperatures). A T6 condition or temper refers to an aluminum alloy solution heat treated and artificially aged. A T7 condition or temper refers to an aluminum alloy solution heat treated and artificially overaged. A T8x condition or temper refers to an aluminum alloy solution heat treated, cold worked, and artificially aged. A T9 condition or temper refers to an aluminum alloy solution heat treated, artificially aged, and cold worked. A W condition or temper refers to an aluminum alloy after solution heat treatment.

[0033] As used herein, the meaning of “room temperature” can include a temperature of from about 15 °C to about 30 °C, for example about 15 °C, about 16 °C, about 17 °C, about 18 °C, about 19 °C, about 20 °C, about 21 °C, about 22 °C, about 23 °C, about 24 °C, about 25 °C, about 26 °C, about 27 °C, about 28 °C, about 29 °C, or about 30 °C.

[0034] All ranges disclosed herein are to be understood to encompass both endpoints and any and all subranges subsumed therein. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g., 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10.

[0035] 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 certain examples of each alloy, the remainder is aluminum, with a maximum wt. % of 0.15 % for the sum of the impurities.

Alloy Compositions

[0036] Aluminum alloy properties are determined at least in part by the composition of the aluminum alloy. In certain aspects, the alloy composition may influence or even determine whether the alloy will have properties adequate for a desired application.

[0037] The alloys described herein are novel aluminum alloys. The alloys exhibit high strength and high formability (e.g., elongation and forming properties suitable for can body stock applications), while including higher amounts of recycled aluminum alloys. The properties of the alloys are achieved at least in part due to the elemental composition of the alloys. In some cases, the novel aluminum alloys described herein can include a higher Mg content and similar levels of Si and Fe compared to conventional AA3104 aluminum alloys, as further described below.

[0038] In some examples, an aluminum alloy as described herein can have the following elemental composition as provided in Table 1.

Table 1

[0039] In some examples, the aluminum alloy as described herein can have the following elemental composition as provided in Table 2.

Table 2

Silicon (Si)

[0040] In some examples, the aluminum alloy described herein includes Si in an amount of up to 0.70 % (e.g., from 0.20 % to 0.40 %, up to 0.20 %, up to 0.40 %, or up to 0.60 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 %, 0.60 %, 0.61 %, 0.62

%, 0.63 %, 0.64 %, 0.65 %, 0.66 %, 0.67 %, 0.68 %, 0.69 %, or 0.70 % Si. All expressed in wt.

Iron (Fe)

[0041] In some examples, the aluminum alloy described herein also includes Fe in an amount of up to 0.80 % (e.g., from 0.40 % to 0.60 %, up to 0.20 %, up to 0.40 %, or up to 0.60 %) based on the total weight of the alloy. For example, the alloy can include 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 %,

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 %, 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 expressed in wt. %. In some embodiments, an aluminum alloy composition including less than 0.20 wt. % Fe may result in processing defects. For example, the aluminum alloy may have poor runnability due to excess die build up. Runnability refers to whether an aluminum alloy includes defects or jams during the process of producing the aluminum alloy. Additionally, including less than 0.20 wt. % Fe in the aluminum alloy composition may limit the amount of recycled aluminum materials that can be used in the aluminum alloy.

Copper (Cu)

[0042] In some examples, the aluminum alloy described herein includes Cu in an amount of from up to 0.60 % (e.g., from 0.10 % to 0.30 %, up to 0.20 %, or up to 0.40 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 % Cu. All expressed in wt. %.

Manganese (Mn)

[0043] In some examples, the aluminum alloy described herein can include Mn in an amount from 0.80 % to 1 .50 % (e.g., from 0.80 % to 1 .40 %, from 0.85 % to 1 .30 %, from 0.90 % to 1.20 %, from 0.95 % to 1.25 %, or from 0.80 % to 1.00 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 %, 1.40 %, 1.41 %, 1.42 %, 1.43 %,

1.44 %, 1.45 %, 1.46 %, 1.47 %, 1.48 %, 1.49 %, or 1.50 % Mn. All expressed in wt. %.

Magnesium (Mg)

[0044] In some examples, the aluminum alloy described herein can include Mg in an amount from 1.30 % to 2.00 % (e.g., from 1.35 % to 1.50 %, from 1.40 % to 1.70 %, from 1.30

% to 1.65 %, or from 1.35 % to 1.90 %) based on the total weight of the alloy. For example, the alloy can include 1.30 %, 1.31 %, 1.32 %, 1.33 %, 1.34 %, 1.35 %, 1.36 %, 1.37 %, 1.38 %, 1.39

%, 1.40 %, 1.41 %, 1.42 %, 1.43 %, 1.44 %, 1.45 %, 1.46 %, 1.47 %, 1.48 %, 1.49 %, 1.50 % 1.51 %, 1.52 %, 1.53 %, 1.54 %, 1.55 %, 1.56 %, 1.57 %, 1.58 %, 1.59 %, 1.60 %, 1.61 %, 1.62 %, 1.63 %, 1.64 %, 1.65 %, 1.66 %, 1.67 %, 1.68 %, 1.69 %, 1.70 %, 1.71 %, 1.72 %, 1.73 %, 1.74 %, 1.75 %, 1.76 %, 1.77 %, 1.78 %, 1.79 %, 1.80 %, 1.81 %, 1.82 %, 1.83 %, 1.84 %, 1.85 %, 1.86 %, 1.87 %, 1.88 %, 1.89 %, 1.90 %, 1.91 %, 1.92 %, 1.93 %, 1.94 %, 1.95 %, 1.96 %, 1.97 %, 1.98 %, 1.99 %, or 2.00 % Mg. All expressed in wt. %.

[0045] In some cases, the novel aluminum alloys described herein can include a Mg content that is higher than the Mg content of conventional 3xxx series aluminum alloys for can body stock applications (e.g., 0.80 wt. % to 1.30 wt. %). For instance, the novel aluminum alloys may include a Mg content up to about 54 % higher than the Mg content of the conventional 3xxx series aluminum alloys for can body stock applications. Additionally, the novel aluminum alloys described herein can include one or more of Cu or Mn in lower amounts compared to the conventional 3xxx series aluminum alloys. For example, the aluminum alloy may include lower Cu content or Mn content in the aforementioned amounts to compensate for the increased content of Mg in the novel aluminum alloys described herein. Decreasing the Cu content and the Mn content can compensate for Mg solid solution hardening, enabling improved canning performance. Due to the increased Mg content and decreased Cu content and Mn content, producing the novel aluminum alloys can avoid adding additional alloying elements (e.g., Mg, Cu, Mn, etc.) to the aluminum alloy composition, which can reduce costs.

Chromium (Cr)

[0046] In some examples, the aluminum alloy described herein includes Cr in an amount of up to 0.30 % (e.g., up to 0.20 %, up to 0.10 %, up to 0.05 %, up to 0.03 %, 0.05 % to 0.10%, or 0.06 % to 0.10 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 expressed in wt. %.

Zinc (Zn)

[0047] In some examples, the aluminum alloy described herein includes Zn in an amount of up to 0.60 % (e.g., up to 0.20 %, up to 0.25 %, up to 0.30 %, up to 40 %, up to 50 %, from 0.10 % to 0.40 %, from 0.15 % to 0.35 %, or from 0.20 % to 0.30 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 % Zn. In some cases, Zn is not present in the alloy (i.e., 0 %). All expressed in wt. %.

Titanium (Ti)

[0048] In some examples, the aluminum alloy described herein includes Ti in an amount of up to 0.10 % (e.g., up to 0.05 %, up to 0.03 %, 0.05 % to 0.10%, or 0.06 % to 0.10 %) based on the total weight of the alloy. For example, the alloy can include 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 % Ti. In some cases, Ti is not present in the alloy (i.e., 0 %). All expressed in wt. %.

Minor Elements

[0049] Optionally, the aluminum alloys described herein can further include other minor elements, sometimes referred to as impurities, in amounts of 0.05 % or below, 0.04 % or below, 0.03 % or below, 0.02 % or below, or 0.01 % or below. These impurities may include, but are not limited to Sc, V, Ni, Hf, Zr, Sn, Ga, Ca, Bi, Na, Pb, or combinations thereof. Accordingly, Sc, V, Ni, Hf, Zr, Sn, Ga, Ca, Bi, Na, or Pb may be present in alloys in amounts of 0.05 % or below, 0.04 % or below, 0.03 % or below, 0.02 % or below, or 0.01 % or below. The sum of all impurities does not exceed 0.15 % (e.g., 0.10 %). All expressed in wt. %. The remaining percentage of each alloy can be aluminum.

Recycled Content

[0050] The aluminum alloys described herein can tolerate higher amounts of recycled aluminum alloy scrap and still exhibit desirable mechanical properties. The impact of the impurities and/or alloying elements on the mechanical properties of the aluminum alloy is reduced by providing a tailored aluminum alloy composition to compensate for the impurities. This enables a higher amount of less expensive, higher impurity recycled aluminum materials (e g., used beverage can) for producing aluminum alloys that can still exhibit desirable properties. The aluminum alloy compositions described herein can include higher amounts of recycled aluminum alloy (e.g., at least 60 wt. %) with little or no additional primary aluminum and little to no additional alloying elements (e.g., Cu or Mn).

[0051] In some embodiments, the aluminum alloy composition described herein provides a composition that is well-suited for utilizing used beverage can (UBC) scrap or other aluminum alloy containers as recycled material. UBC scrap is a mixture of various aluminum alloys (e.g., from different aluminum alloys used for can bodies and can ends) and can often include foreign substances, such as rainwater, drink remainders, organic matter, and other materials (e.g., paints and laminated films). UBC scrap generally includes a mixture of metal from various aluminum alloys, such as metal from can bodies (e.g., AA3104, AA3004, or other 3xxx series aluminum alloys) and can ends (e.g., AA5182 or other 5xxx series aluminum alloys). UBC scrap can be shredded and de-coated or de-lacquered prior to being melted for use as liquid metal stock in casting a new metal product.

[0052] As discussed herein, the aluminum alloy composition described herein reduces the compositional gap between can body stock and can end stock and between can end stock and can tab stock (both of which may be made with an AA5192 alloy). This allows the use of more recycled aluminum alloy, particularly UBC scrap, for producing can body stock and reduces the amount of both primary aluminum and additional alloying elements (e.g., Cu or Mn). In some aspects, the aluminum alloys described herein include a high amount of recycled aluminum scrap at or greater than 60 % (e.g., at or greater than 65 %, at or greater than 70 %, at or greater than 75 %, at or greater than 80 %, at or greater than 85 %, at or greater than 90 %, at or greater than 95 %, or at 100 %.). In terms of ranges, the aluminum alloys described herein can include from 60 % to 100 % UBC scrap (e.g., from 65 % to 95 %, from 60 % to 90 %, from 65 % to 85 %, from 60 % to 80 %, from 70 % to 100 %, or from 75 % to 90 %). All percentages are expressed in wt. %.

[0053] As discussed above, in some aspects, the UBC scrap includes a mixture of alloys including a 3xxx series aluminum alloy and a 5xxx series aluminum alloy. In some aspects, the UBC scrap can include a 5xxx series aluminum alloy in an amount from 0 % to 75 % (e.g., from 5 % to 70 %, from 10 % to 65 %, from 15 % to 60 %, from 20 % to 50 %, or from 25 % to 40 %), based on the total weight of the recycled scrap. For example, the UBC scrap can include greater than 0 % of a 5xxx series aluminum alloy scrap (e g., greater than 1 %, greater than 5 %, greater than 10 %, greater than 15 %, greater than 20 %, or greater than 25 %), based on the total weight of the UBC scrap. All are expressed in wt. %.

[0054] In some aspects, the UBC scrap can include a 3xxx series aluminum alloy scrap (from the mixed alloy scrap) in an amount from 0 % to 75 % (e.g., from 5 % to 70 %, from 10 % to 65 %, from 15 % to 60 %, from 20 % to 50 %, or from 25 % to 40 %), based on the total weight of the UBC scrap. For example, the UBC scrap can include greater than 0 % of a 3xxx series aluminum alloy scrap (e.g., greater than 1 %, greater than 5 %, greater than 10 %, greater than 15 %, greater than 20 %, or greater than 25 %), based on the total weight of the UBC scrap. All are expressed in wt. %.

[0055] In some aspects, the aluminum alloys described herein include less than 15 % primary aluminum (e.g., less than 14 %, less than 13 %, less than 12 %, less than 11 %, less than 10 %, less than 9 %, less than 8 %, less than 7 %, less than 6 %, less than 5 %, less than 4 %, less than 3 %, less than 2 %, or less than 1%). All are expressed in wt. %. In some cases, the aluminum alloys described herein may not include primary aluminum.

Properties

[0056] In some examples, an aluminum alloy product (e.g., an aluminum alloy sheet) produced from the aluminum alloys described herein can have a yield strength of about 200 MPa or greater. In some cases, the yield strength is from about 200 MPa to about 350 MPa, or anywhere in between. The aluminum alloy products described herein can exhibit the yield strengths as described herein when measured in a longitudinal (L) direction, a transverse (T) direction, and/or in a diagonal (D) direction, each respective to the rolling direction.

[0057] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have an ultimate tensile strength of about 250 MPa or greater. In some cases, the ultimate tensile strength is from about 250 MPa to about 450 MPa, or anywhere in between. The aluminum alloy products described herein can exhibit the ultimate tensile strengths as described herein when measured in a longitudinal (L) direction, a transverse (T) direction, and/or in a diagonal (D) direction, each respective to the rolling direction. Methods of Making Aluminum Alloys

[0058] FIG. 1 is a flowchart depicting a process 100 for producing an aluminum alloy product from recycled aluminum scrap, according to certain aspects of the present disclosure. At block 102, recycled aluminum scrap (e.g., UBC scrap) is melted. The scrap can be melted in any suitable vessel (e.g., a rotary furnace, a crucible furnace, etc ). The liquid metal resulting from melting the recycled aluminum scrap can include alloying elements in amounts that would render the liquid metal a non-standard alloy, such as an alloy that is not conventionally used for beverage parts (e.g., can ends or can bodies). For example, if the recycled aluminum scrap is UBC scrap, the liquid metal may include a combination of 3xxx series aluminum alloys conventionally used to produce can body stock and 5xxx series aluminum alloys conventionally used to produce can end stock.

[0059] At block 104, additional alloying elements optionally can be added to the liquid metal to produce a modified liquid metal with suitable amounts of alloying elements. Adding alloying elements can include melting raw elements or mixtures of aluminum and the alloying elements into the liquid metal from block 102. In additional or alternative implementations, primary aluminum may be added to the liquid metal to dilute certain alloying elements.

[0060] The modified liquid metal from block 104 can be cast to result in a cast product 114. In some cases, if no additional alloying elements or primary aluminum is added to the liquid metal of block 102, the liquid metal of block 102 can be directly cast to produce the cast product 114. The aluminum alloys described herein can be cast into the cast product 114 using a direct chill (DC) process or can optionally be cast using a continuous casting (CC) process. The casting process is performed according to standards commonly used in the aluminum industry as known to one of skill in the art. At block 106, a DC casting device can be used to produce the cast product 114. The DC casting process can form a cast product (e.g., an ingot). Optionally, instead of using a DC casting device, as described with reference to block 106, the modified liquid metal from block 104 can be cast using a CC device at block 107 to produce the cast product 114. The CC process may include, but is not limited to, the use of twin belt casters, twin roll casters, or block casters. In some examples, the casting process is performed by a CC process to form a slab, a strip, or the like. The cast product 114 resulting from block 106 or block 107 can include less than 15 wt. % of primary aluminum (e.g., less than 14 wt. %, less than 13 wt. %, less than 12 wt. %, less than 11 wt. %, less than 10 wt. %, less than 9 wt. %, less than 8 wt. %, less than 7 wt. %, less than 6 wt. %, less than 5 wt. %, less than 4 wt. %, less than 3 wt. %, less than 2 wt. %, or less than 1 wt. % of primary aluminum).

[0061] The cast product can then be subjected to further processing steps. Optionally, the further processing steps can be used to prepare aluminum alloy products (e.g., sheets, shates, or plates). Such processing steps include, but are not limited to, a homogenization step, a hot rolling step, a cold rolling step, and an optional lacquering step. Other optional processing steps can include a degreasing step or a lubricating step. The processing steps are described below in relation to a cast product. However, the processing steps can also be used for a cast slab or strip, using modifications as known to those of skill in the art.

Homogenization

[0062] At block 108, the cast product 114 of block 106 may be heated during a homogenization step to a homogenization temperature, such as a temperature ranging from about 400 °C to about 600 °C. For example, the cast product 114 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, 600 °C, or anywhere in between. In some embodiments, the heating rate to the peak metal temperature can be about 70 °C/hour or less, about 60 °C/hour or less, or about 50 °C/hour or less. The cast product 114 may then be allowed to soak (i.e., held at the indicated temperature) for a period of time to form a homogenized product 116. In some examples, the total time for the homogenization step, including the heating and soaking phases, can be up to about 10 hours (e.g., up to 9 hours, up to 8 hours, up to 7 hours, up to 6 hours, up to 5 hours, up to 4 hours, up to 3 hours, up to 2 hours, or up to 1 hour).

Hot Rolling

[0063] Following the homogenization step, a hot rolling step can be performed at block 110. In certain aspects, the homogenized product 116 can be hot rolled using a rolling mill to produce a hot rolled product 118 having an intermediate gauge. In additional or alternative aspects, the cast product 114 of block 107 can be hot rolled at block 110 to produce the hot rolled product 118. The hot rolling step can include a hot reversing mill operation or a hot tandem mill operation. Prior to the start of hot rolling, the homogenized product 116 can be allowed to cool to a desired temperature (e.g., from about 200 °C to about 425 °C). For example, the homogenized product 116 can be allowed to cool to a temperature of from about 200 °C to about 400 °C, about 250 °C to about 375 °C, about 300 °C to about 425 °C, or from about 350 °C to about 400 °C. The homogenized product 116 can then be hot rolled at a hot rolling temperature from about 200 °C to about 550 °C to produce a hot rolled product 118 (e.g., a hot rolled plate, a hot rolled shate, or a hot rolled sheet). For example, the hot rolling step may be performed at a hot rolling temperature of about 250 °C to about 300 °C, about 300 °C to about 500 °C, or from about 350 °C to about 450 °C.

Cold Rolling

[0064] At block 112, the hot rolled product 118 can be cold rolled using cold rolling mills into thinner aluminum alloy products, such as a final gauge rolled product 120. In certain aspects, the cold rolling step results in a cold work thickness reduction of the hot rolled product 118 of at least 80 % (e.g., at least 90%, at least 95%, or from about 85% to about 95%). For example, the cold rolling step reduces a thickness of the hot rolled product 118 by about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, or about 95%. The final gauge rolled product 120 can have a gauge between about 0.20 to about 0.35 mm (e.g., between about 0.20 to about 0.30 mm) or about 0.008 to about 0.013 inches. Optionally, the final gauge rolled product 120 can have a gauge of about 0.20 mm, about 0.21 mm, about 0.22 mm, about 0.23 mm, about 0.24 mm, about 0.25 mm, about 0.26 mm, about 0.27 mm, about 0.28 mm, about 0.29 mm, about 0.30 mm, about 0.31 mm, about 0.32 mm, about 0.33 mm, about 0.34 mm, or about 0.35 mm. In some embodiments, the cold rolling step may include one or more cold rolling steps to achieve a desired gauge thickness reduction. Optionally, the process for producing the aluminum alloy can include an annealing step applied during or after the cold rolling step (e.g., between one or more cold rolling steps).

Degreasing

[0065] Following the cold rolling step, a number of optional steps can be performed. FIG. 2 is a flowchart of a process 200 for treating a final gauge rolled product 120 produced using a high-strength, high recycled content aluminum alloy prior to downstream processing for can body stock applications according to certain aspects of the present disclosure. For example, the process 200 described herein can optionally include at least one degreasing step applied to the final gauge rolled product 120 at block 202. The term “degreasing,” as used herein, includes processing the final gauge rolled product 120 to remove residual oil accumulated on the surface from the hot rolling and cold rolling processes. The degreasing step can also remove residual surface debris, rolling oil, and aluminum fines from the rolling processes. The degreased surface gives an improved surface appearance to the final gauge rolled product 120 and reduces the build-up of aluminum fines during downstream processing, for example during a cupping process to produce can bodies. The degreasing agent for use in the degreasing step can include water and/or solvents. Optionally, the water for use in the degreasing step can be hot water (i.e., water having a temperature of at least about 35 °C, such as from about 35 °C to about 100 °C). In some cases, the degreasing agents can include acidic or alkaline agents. For example, suitable acidic agents for use in the degreasing step include phosphoric acid, sulfuric acid, hydrochloric acid, or a mixture of these. In some cases, the degreasing agent can include a wetting agent. Optionally, the degreasing agent can be used in combination with electrochemical cleaning. In certain cases, the level of degreasing is controlled by the concentration of the agents, current density, degreasing time, and/or temperature in the degreasing section. After degreasing, the final gauge rolled product 120 may be rinsed with water and dried prior to lubrication. In some aspects, a post-annealing process can be applied. For example, the post-annealing process may comprising soaking for up to 5 hours at a temperature from 150 °C to 250 °C.

Lubricating

[0066] As another example, after the cold rolling step, the final gauge rolled product 120 may optionally undergo a lubricating step at block 204. The process described herein can optionally include at least one lubricating step applied to the aluminum alloy product. The term “lubricating,” as used herein, includes processing the aluminum alloy product to apply a lubricant for subsequent cupping production. Optionally, the lubricant applied can be a dry film lubricant. In some cases, the lubricant can be applied uniformly. In some cases, the lubricating step eliminates the need for the use of additional lubricant during downstream processing (e.g., during the cupping process).

Methods of Using and Downstream Processing

[0067] The aluminum alloy products and methods described herein can be used for preparing beverage cans, food containers, or any other desired application. In some examples, the aluminum alloy products and methods can be used to prepare beverage can bodies. The aluminum alloy products as described herein can be used in downstream processing at block 208, such as in a cupping process. The cupping process can involve cutting circular discs of the final gauge rolled product 120 and forming the circular discs into cups that can be further processed into beverage can bodies. The beverage cans prepared using the beverage can bodies can have a fill volume or can size of 8.4 ounce, 12 ounce standard (e.g., having a height of approximately 122.22 mm), 12 ounce sleek (e g., having a height of approximately 156.59 mm), 16 ounce, 19.2 ounce, 24 ounce, 222 mb, 250 mb, 330 mb, 350 mb, or 500 mb.

Lacquering

[0068] Subsequently, the beverage can bodies can optionally undergo a lacquering step at block 206. The lacquering step can apply a coating on the beverage can bodies at a temperature from 150 °C to 400 °C for 1 second to 10 minutes. For example, the beverage can bodies can be lacquered at a temperature of from 150 °C to 400 °C, from 200 °C to 400 °C, from 250 °C to 350 °C, from 200 °C to 300 °C, or from 300 °C to 400 °C. The peak metal temperature of the beverage can bodies during the lacquering process may range from 100 °C to 300 °C (e.g., from 125 °C to 275 °C, from 150 °C to 250 °C, or from 200 °C to 300 °C).

Illustrations

[0069] Illustration 1 : An aluminum alloy, comprising up to 0.70 wt. % Si, up to 0.80 wt. % Fe, up to 0.60 wt. % Cu, 0.80 - 2.00 wt. % Mn, 1.30 - 1.50 wt. % Mg, up to 0.60 wt. % Zn, up to 0.30 wt. % Cr, up to 0.10 wt. % Ti, up to 0.15 wt. % impurities, and Al, wherein the aluminum alloy comprises at least 60 wt. % of recycled aluminum scrap.

[0070] Illustration 2: The aluminum alloy of Illustration 1, comprising 0.20 - 0.40 wt. % Si, 0.40 - 0.60 wt. % Fe, 0.10 - 0.30 wt. % Cu, 0.80 - 1.00 wt. % Mn, 1.35 - 1.50 wt. % Mg, up to 0.25 wt. % Zn, up to 0.05 wt. % Cr, up to 0.05 wt. % Ti, up to 0.15 wt. % impurities, and Al.

[0071] Illustration 3: The aluminum alloy of Illustration 1, wherein the aluminum alloy comprises greater than 75 wt. % of recycled aluminum scrap.

[0072] Illustration 4: The aluminum alloy of Illustration 1, wherein the aluminum alloy comprises less than 15 wt. % of primary aluminum.

[0073] Illustration 5: The aluminum alloy of Illustration 4, wherein the aluminum alloy comprises less than 5 wt. % of primary aluminum.

[0074] Illustration 6: The aluminum alloy of any of Illustrations 1-5, wherein the aluminum alloy exhibits a yield strength of at least 200 MPa, preferably from 200 to 350 MPa. [0075] Illustration 7: The aluminum alloy of any of Illustrations 1-6, wherein the aluminum alloy exhibits an ultimate tensile strength of at least 250 MPa, preferably from 250 to 450 MPa.

[0076] Illustration 8: The aluminum alloy of any of Illustrations 1-7, wherein the aluminum alloy comprises up to 100 wt. % of recycled aluminum scrap.

[0077] Illustration 9: The aluminum alloy of any of Illustrations 1-8, wherein the recycled aluminum scrap comprises used beverage can scrap.

[0078] Illustration 10: The aluminum alloy of Illustration 9, wherein the used beverage can scrap contains a mixture of recycled metal from can ends and can bodies.

[0079] Illustration 11 : A can body stock comprising the aluminum alloy of any of Illustrations 1-10.

[0080] Illustration 12: A method of producing an aluminum alloy product, the method comprising: casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises the aluminum alloy of Illustration 1; homogenizing the cast product; hot rolling the cast product to produce a hot rolled product; cold rolling the hot rolled product to produce an aluminum alloy product; and optionally annealing the aluminum alloy product.

[0081] Illustration 13: The method of Illustration 12, wherein the casting step comprises continuously casting the aluminum alloy to form the cast product.

[0082] Illustration 14: The method of Illustration 12, wherein the casting step comprises direct chill casting the aluminum alloy to form the cast product.

[0083] Illustration 15: The method of Illustration 12, further comprising lacquering and curing the aluminum alloy product.

[0084] Illustration 16: The method of Illustration 12, wherein the aluminum alloy comprises greater than 75 wt. % recycled aluminum scrap.

[0085] Illustration 17: The method of Illustration 12, wherein the aluminum alloy comprises less than 15 wt. % of primary aluminum.

[0086] Illustration 18: The method of Illustration 17, wherein the aluminum alloy comprises less than 5 wt. % of primary aluminum.

[0087] Illustration 19: A metal product, wherein the metal product is prepared by a method comprising any of Illustrations 12-18.

[0088] Illustration 20: The metal product of Illustration 19, wherein the metal product is can body stock. [0089] Illustration 21: The metal product of Illustration 19, wherein the metal product is a beverage can comprising can body stock prepared using the aluminum alloy of Illustration 1 and can end stock prepared using a 5xxx series aluminum alloy.

[0090] Illustration 22: The metal product of Illustration 21, wherein the can end stock is prepared using AA5182.

[0091] Illustration 23: The metal product of Illustration 19, wherein the metal product is a beverage can comprising can end stock prepared using the aluminum alloy of Illustration 1 and can body stock and/or can end stock prepared using a 5xxx series aluminum alloy.

[0092] The following examples will serve to further illustrate the present invention without, however, constituting any limitation thereof. On the contrary, it is to be clearly understood that resort may be had to various embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to those skilled in the art without departing from the spirit of the invention.

[0093] During the studies described in the following examples, conventional procedures were followed, unless otherwise stated. Some of the procedures are described below for illustrative purposes.

EXAMPLES

Example 1

[0094] Sample aluminum alloys were tested to determine the properties of the aluminum alloys described herein. Comparative Examples 1-3 and Example 1 were prepared according to the methods described herein. Comparative Examples 1-3 were prepared from conventional 3xxx series aluminum alloys that are employed as can body stock. Specifically, Comparative Example 1 was prepared from AA3004 aluminum alloy, Comparative Example 2 was prepared from AA3104 aluminum alloy, and Comparative Example 3 was prepared from AA3104 aluminum alloy. Example 1 was prepared from aluminum alloys described herein. Table 3 provides the aluminum alloy composition for each of Comparative Examples 1-3 and Example 1.

[0095] As shown in Table 3, Comparative Examples 1-3 includes lower amounts of Mg compared to Example 1. Since Example 1 has a similar composition to Comparative Example 3 (i.e., AA3104 aluminum alloy), these aluminum alloys can be produced from higher amounts of recycled UBC scrap that contain similar amounts of Fe, Si, Cu, and Mn. This eliminates the need for diluting the aluminum alloys of Example 1 with primary aluminum or adding additional hardening elements, thereby conserving manufacturing costs and environmental costs. Additionally, by maintaining the aluminum alloy compositions that may be similar to AA3104 aluminum alloy, the re-melting process may be simplified to reduce process changes during fabrication. The aluminum alloy composition of Example 1 is similar to conventional AA3104 aluminum alloy for can body stock except having higher Mg content, enabling a simpler remelting process that can form a complete loop while minimizing alloy composition changes.

[0096] Furthermore, the recycled content will be significantly higher due to much lower needs of primary aluminum or hardening elements. In contrast, conventional 3xxx series aluminum alloys for can body stock applications would require dilution of the Mg content when casting from UBC. As shown in Table 4, Comparative Example 3 includes 6.90 wt. % primary aluminum, whereas Example 1 includes 4.30 wt. % primary aluminum. The aluminum alloys described herein include at least 2.70 wt. % less primary aluminum than AA3104 aluminum alloy, which can be a substantial cost savings and can improve sustainability through reduced usage of primary aluminum. Additionally, Example 1 can incorporate higher amounts of UBC scrap in place of primary aluminum because the aluminum alloys can tolerate higher amounts of Mg. For example, Comparative Example 3 includes 75.00 wt. % UBC scrap, whereas Example 1 includes 77.90 wt. % UBC scrap.

[0097] Moreover, the increased Mg content combined with lower levels of Cu and Mn increase the recycled content of the aluminum alloys while still providing comparable properties to current 3xxx series aluminum alloys for can body stock applications. The alloy composition can compensate for the higher Mg content with a slight decrease of Mn and Cu to increase the recycled content while still maintaining comparable physical properties as current 3xxx series aluminum alloys (e.g., AA3104) for can body stock applications.

[0098] All patents, publications, and abstracts cited above are incorporated herein by reference in their entireties. Various embodiments of the invention have been described in fulfdlment of the various objectives of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptions thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the present invention as defined in the following claims.

Claims

WHAT IS CLAIMED IS:

1. An aluminum alloy, comprising up to 0.70 wt. % Si, up to 0.80 wt. % Fe, up to 0.60 wt. % Cu, 0.80 - 1.50 wt. % Mn, 1.30 - 2.00 wt. % Mg, up to 0.60 wt. % Zn, up to 0.30 wt. % Cr, up to 0.10 wt. % Ti, up to 0.15 wt. % impurities, and Al, wherein the aluminum alloy comprises at least 60 wt. % of recycled aluminum scrap.

2. The aluminum alloy of claim 1, comprising 0.20 - 0.40 wt. % Si, 0.40 - 0.60 wt. % Fe, 0.10 - 0.30 wt. % Cu, 0.80 - 1.00 wt. % Mn, 1.35 - 1.50 wt. % Mg, up to 0.25 wt. % Zn, up to 0.05 wt. % Cr, up to 0.05 wt. % Ti, up to 0.15 wt. % impurities, and Al.

3. The aluminum alloy of claim 1, wherein the aluminum alloy comprises greater than 75 wt. % of recycled aluminum scrap.

4. The aluminum alloy of claim 1, wherein the aluminum alloy comprises less than 15 wt. % of primary aluminum.

5. The aluminum alloy of claim 4, wherein the aluminum alloy comprises less than 5 wt. % of primary aluminum.

6. The aluminum alloy of any of claims 1-5 wherein the aluminum alloy exhibits a yield strength of at least 200 MPa, preferably from 200 to 350 MPa.

7. The aluminum alloy of any of claims 1-6, wherein the aluminum alloy exhibits an ultimate tensile strength of at least 250 MPa, preferably from 250 to 450 MPa.

8. The aluminum alloy of any of claims 1-7, wherein the aluminum alloy comprises up to 100 wt. % of recycled aluminum scrap.

9. The aluminum alloy of any of claims 1-8, wherein the recycled aluminum scrap comprises used beverage can scrap.

10. The aluminum alloy of claim 9, wherein the used beverage can scrap contains a mixture of recycled metal from can ends and can bodies.

11. A food or beverage packaging comprising the aluminum alloy of any of claims 1-10.

12. A can body stock comprising the aluminum alloy of any of claims 1-10.

13. A method of producing an aluminum alloy product, the method comprising: casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises the aluminum alloy of claim 1; homogenizing the cast product; hot rolling the cast product to produce a hot rolled product; cold rolling the hot rolled product to produce an aluminum alloy product; and optionally annealing the aluminum alloy product.

14. The method of claim 13, wherein the casting step comprises continuously casting the aluminum alloy to form the cast product.

15. The method of claim 13, wherein the casting step comprises direct chill casting the aluminum alloy to form the cast product.

16. The method of claim 123 further comprising lacquering and curing the aluminum alloy product.

17. The method of claim 13, wherein the aluminum alloy comprises greater than 75 wt. % recycled aluminum scrap.

18. The method of claim 13, wherein the aluminum alloy comprises less than 15 wt. % of primary aluminum.

19. The method of claim 18, wherein the aluminum alloy comprises less than 5 wt. % of primary aluminum.

20. A metal product, wherein the metal product is prepared by a method comprising any of claims 13-19.

21. The metal product of claim 20, wherein the metal product is food or beverage packaging.

22. The metal product of claim 20, wherein the metal product is can body stock.

23. The metal product of claim 20, wherein the metal product is a beverage can comprising can body stock prepared using the aluminum alloy of claim 1 and can end stock prepared using a 5xxx series aluminum alloy.

24. The metal product of claim 23, wherein the can end stock is prepared using AA5182.

25. The metal product of claim 20, wherein the metal product is a beverage can comprising can end stock prepared using the aluminum alloy of claim 1 and can body stock and/or can end stock prepared using a 5xxx series aluminum alloy.