6xxx series aluminum alloys produced from mixed recycled aluminum alloy scrap for automotive applications

Abstract

Described herein are 6xxx series aluminum produced from mixed recycled aluminum alloy scrap and less than 20 weight percent prime aluminum. Also described herein are methods for producing aluminum alloys from mixed recycled aluminum alloy scrap and less than 20 weight percent prime aluminum. The aluminum alloys and sheets described herein are suitable for automotive applications.

Description

6XXX SERIES ALUMINUM ALLOYS PRODUCED FROM MIXED RECYCLED ALUMINUM ALLOY SCRAP FOR AUTOMOTIVE APPLICATIONSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 570,366, filed March 27, 2024, which is hereby incorporated by reference in its entirety for all intents and purposes.FIELD

[0002] The present disclosure relates to the fields of metallurgy, aluminum alloys, aluminum fabrication, and related fields. In particular, the present disclosure generally provides recycle friendly 6xxx series aluminum alloys produced from a mixture of recycled aluminum alloy scrap sources and includes an excess amount of magnesium (Mg) that can replace existing non-recycle friendly 5xxx series and 6xxx series aluminum alloys. The disclosure also provides various end uses of such products, such as in automotive, transportation, industrial, and other applications.BACKGROUND

[0003] High-strength aluminum alloys are used in many different applications, particularly in applications where strength and durability are required. For example, 6xxx series aluminum alloys have been widely used in automobile applications due to their superior combination of properties including strength-to-weight ratio, formability, weldability, and general corrosion resistance. 6xxx series aluminum alloys are commonly used for automotive structural and closure panel applications in place of steel. Because aluminum alloys are generally about 2.8 times less dense than steel, the use of such materials reduces the weight of the vehicle and allows for substantial improvements in its fuel economy. However, the recyclability of aluminum alloys used in automotive applications is limited because multiple different alloy systems with different compositions are used to produce automotive parts having different properties.

[0004] There is currently no singular alloy that can be used to produce all parts of a vehicle, and multiple different alloy systems are used to produce different parts having specific property requirements (e.g., hemmability, strength, bendability, recyclability). For example, some 6xxx series aluminum alloys may be used to produce structural parts andsome 5xxx series aluminum alloys may be used to produce door inner parts. These parts cannot be recycled to produce new aluminum alloys because of the mixed sources of recycled materials including different amounts of alloying elements.

[0005] Most high strength 6xxx series aluminum alloys currently available on the market (e.g., AA6111 and AA6011) are excess Si alloys, and include Mg, Si, and Cu as hardening elements, where enough Si is required to form Mg2Si phase particles and where Mn and Fe content is generally limited to less than 0.28 wt. % and 0.2 wt.%, respectively. On the other hand, aluminum alloys such as AA5182 and AA5754 contain Si below 0.2 wt. % and Mn and Fe at approximately 0.3 wt. %, and these 5xxx series aluminum alloys are incompatible with 6xxx series aluminum alloy chemistry and cannot be efficiently recycled from mixed 5xxx and 6xxx series aluminum alloy scrap.

[0006] In order to improve circularity and recyclability in the automotive industry, there is a need for new aluminum alloys that can improve the recyclability of mixed 6xxx and 5xxx series aluminum alloy scraps from automotive applications.SUMMARY

[0007] 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.

[0008] Described herein are aluminum alloys that include 0.30 - 0.80 wt. % Si, 0.20 - 0.50 wt. % Fe, 0.10 - 0.60 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 2.00 wt. % Mg, up to 0.20 wt. % Cr, up to 0.20 wt. % Zn, up to 0.15 wt. % Ti, up to 0.15 wt. % of impurities, and Al, where the aluminum alloy includes less than 20 wt.% prime aluminum, and where the aluminum alloy includes Mg2Si phase particles that are present in an amount from 0.8 wt. % to 3.0 wt. %. In some cases, the aluminum alloy includes 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.85 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al. In some cases, the aluminum alloy includes 0.30 - 0.50 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.05 - 0.20 wt. % Mn, 1.4 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al. In some cases, the aluminum alloyincludes 0.50 - 0.70 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.20 - 0.40 wt. % Mn, 0.85 - 1.10 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al. In some cases, the aluminum alloy includes recycled aluminum alloy scrap, where the recycled aluminum alloy scrap includes one or more of up to 15 wt. % 3xxx series recycled aluminum alloy scrap, up to 30 wt. % 5xxx series recycled aluminum alloy scrap, up to 70 wt. % 6xxx series recycled aluminum alloy scrap, or up to 30 wt. % mixed EOL aluminum alloy scrap.

[0009] In some cases, the aluminum alloy includes soluble Q phase particles, wherein after solution heat treating the aluminum alloy, the aluminum alloy comprises less than 1 wt. % of Q phase particles. In some cases, the aluminum alloy includes a ratio of a-Al(FeMn)Si phase particles to Mg2Si phase particles is 9: 1 or greater. In some cases, the total amount of Fe, Mn, and Cr in the aluminum alloy is at least 0.5 wt. %.

[0010] The aluminum alloy can have a yield strength of 220 MPa to 300 MPa in a T8x temper. In some cases, the aluminum alloy is pre-strained. In some cases, the aluminum alloy is in a T4 temper, a T6 temper, or a T8x temper. In some cases, the aluminum alloy is strained from 0.25% to 30%, and the aluminum alloy is substantially free from Type A Luder lines. In some cases, the aluminum alloy exhibits an increase in yield strength from 170 MPa to 270 MPa after a paint bake cycle at a temperature from 140 °C to 180 °C for 10 to 30 minutes.

[0011] Also described herein is a method of producing an aluminum alloy including casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al, wherein the aluminum alloy comprises less than 20 wt.% prime aluminum; homogenizing the cast product; hot rolling the cast product to produce a hot rolled product; cold rolling the rolled product to produce a final gauge rolled product; and solution heat treating the final gauge rolled product. In some cases, the method further includes aging the final gauge rolled product to a T temper. In some cases, the T temper is a T4 temper, a T6 temper, or a T8x temper. In some cases, the method further includes pre-straining the final gauge rolled product after ageing. In some cases, the cast product is cast from an aluminum alloy comprising one or more of Twitch, 5xxx aluminum alloys, 6xxx aluminum alloys, or can body stock. In some cases, the final gauge rolled product includes Q phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves the Qphase particles and the final gauge rolled product is substantially free of Q phase particles after the solution heat treatment. In some cases, the final gauge rolled product includes Mg2Si phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 600 °C for 5 minutes to 30 minutes dissolves at least half of the Mg2Si phase particles and the final gauge rolled product comprises from 0.8 wt. % to 3 wt. % Mg2Si phase particles after the solution heat treatment.

[0012] Further aspects, objects, and advantages will become apparent upon consideration of the detailed description and figures that follow.BRIEF DESCRIPTION OF THE FIGURES

[0013] FIGs. 1A-1C show light microscopy images of the microstructure of Example Alloy A taken in a longitudinal direction through the reroll thickness at a first edge location (FIG. 1 A), at a center location (FIG. IB), and at a second edge location (FIG. 1C).

[0014] FIGs. 1D-1F show light microscopy images of the microstructure of Example Alloy B taken in a longitudinal direction through the reroll thickness at a first edge location (FIG. ID), at a center location (FIG. IE), and at a second edge location (FIG. IF).

[0015] FIGs. 2A and 2B show light microscopy images of the microstructure of Example Alloy A before solution heat treatment (SHT) (FIG. 2A) and Example Alloy B before solution heat treatment (FIG. 2B).

[0016] FIGs. 2C and 2D show light microscopy images of the microstructure of Example Alloy A after SHT (FIG. 2C) and Example Alloy B after solution heat treatment (FIG. 2D).

[0017] FIG. 3A provides a plot of an X-ray diffraction spectrum of particles extracted from the matrix of Example Alloy B before (F temper) and after (T4 temper) SHT.

[0018] FIG. 3B provides a plot of an X-ray diffraction spectrum of particles extracted from the matrix of Example Alloy A before (F temper) and after (T4 temper) SHT.

[0019] FIG. 4A provides a graph showing the relative amounts (wt. %) of different particles in the microstructure of Example Alloy A before (F temper) and after SHT (T4 temper).

[0020] FIG. 4B provides a graph showing the relative amounts (wt. %) of different particles in the microstructure of Example Alloy B before (F temper) and after SHT (T4 temper).

[0021] FIG. 5A provides a graph showing an engineering stress strain curve of a AA5182 aluminum alloy in an O-temper.

[0022] FIG. 5B provides a graph showing an engineering stress strain curve of Example Alloy B.

[0023] FIG. 5C provides a graph showing an engineering stress strain curve of Example Alloy A.

[0024] FIG. 6 provides a graph showing the effect of natural ageing over a period of time (x-axis, days) on transverse yield strength (MPa) of Example Alloy A after being subjected to solution heat treatment at 560 °C and Example B after being subjected to solution heat treatment at 535 °C and 550 °C.

[0025] FIG. 7A provides a graph showing the transverse yield strength (MPa) of Example Alloy B at 535 °C SHT.

[0026] FIG. 7B provides a graph showing the transverse yield strength (MPa) of Example Alloy B at 550 °C SHT.

[0027] FIG. 7C provides a graph showing the transverse yield strength (MPa) of Example Alloy A at 560 °C SHT.

[0028] FIG. 8A provides a graph showing the effect of ageing at elevated temperature over a period of time (x-axis, hours) of Example Alloy B after being subjected to solution heat treatment at 535 °C SHT and aged at 140 °C, 160 °C, 180 °C, and to a T4 temper.

[0029] FIG. 8B provides a graph showing the effect of ageing at elevated temperature over a period of time (x-axis, hours) of Example Alloy B after being subjected to solution heat treatment at 550 °C SHTand aged at 140 °C, 160 °C, 180 °C, and to a T4 temper.

[0030] FIG. 8C provides a graph showing the effect of ageing at elevated temperature over a period of time (x-axis, hours) of Example Alloy A after being subjected to solution heat treatment at 560 °C PMT and aged at 140 °C, 160 °C, 180 °C, and to a T4 temper.

[0031] FIG. 9A-9B provides light microscopy images of the microstructure of Example Alloy B taken in a longitudinal direction through the sample thickness after being subjected to a solution heat treatment at 550 °C, as polished in a T4 temper (FIG. 9A) and the grain structure (FIG. 9B).

[0032] FIG. 10A provides a picture of the blank shape of a sheet from an Example Alloy B before stamping.

[0033] FIG. 10B provides a picture of the stamped panel of a sheet from Example Alloy B after stamping.DETAILED DESCRIPTION

[0034] Described herein are novel aluminum alloys produced from a combination of recycled aluminum alloy scrap sources and exhibit a combination of good strength and formability. The aluminum alloy described herein can be produced from a combination of recycled aluminum alloy scrap including can body stock (CBS), 6xxx series aluminum alloy scrap, 5xxx series aluminum alloy scrap, and Twitch scrap, with minimal amounts of prime aluminum. In some embodiments, the aluminum alloys described herein include excess amounts of Mg (e.g., excess Mg aluminum alloys) and are primarily hardened by Mg2Si and / or Q secondary phase particles. As used herein, excess Mg aluminum alloys refers to aluminum alloys having a weight ratio of Mg to Si greater than 1 : 1. Additionally, the aluminum alloys described herein can tolerate higher amounts of Fe, Mn, and Cu-containing dispersoids than conventional 6xxx series aluminum alloys, thus allowing for new sources of recycled aluminum alloy scrap sources to be incorporated (e.g., mixed 5xxx / 6xxx series aluminum alloys). Beneficially, the aluminum alloy described herein improves recyclability and circularity of 6xxx series aluminum alloys and still maintains good strength and formability properties.

[0035] High strength 6xxx series aluminum alloys are typically used for strength-critical parts, for example, in automobile applications or in roll forming applications. For example, AA6111 and AA6011 aluminum alloys are used to produce structural parts of an automobile. Both of these 6xxx series aluminum alloys have lower amounts of Fe, Mn, and Cr, as well as Mg and Zn, than are present in recycled aluminum alloy scrap sources, as these elements can form coarse particles detrimental to the formability. Excess Mg that is present in conventional 6xxx series alloys in an amount that is more than required to form Mg2Si phase particles can reduce the solubility of those particles during solution heat treatment and can negatively impact age hardening. However, various 5xxx and 6xxx series aluminum alloy scrap sources contain higher amounts of Fe, Mn, Cr, Mg, and Zn than conventional 6xxx series alloys, limiting their utility in the production of conventional 6xxx series alloys (and thus reducing recyclability and circularity).

[0036] The aluminum alloys described herein provide an alternative to conventional 6xxx series aluminum alloys. Beneficially, the aluminum alloys described herein provide a cleaner, unified 6xxx series aluminum alloy that improves recyclability and circularity of high strength 6xxx series aluminum alloys. Specifically, the present disclosure provides a 6xxx series aluminum alloy including excess Mg (0.85 to 2.00 wt. %) that exhibits good strength and formability properties. The aluminum alloys described herein can be produced from amixture of different 6xxx series aluminum alloys, a mixture of 5xxx and 6xxx series aluminum alloy scrap, as well as other types of recycled aluminum alloy scrap without the need for segregation or sorting, which is a major hurdle for recycling. Additionally, the composition window of the aluminum alloys described herein is finely tuned in order to accept high recycling content (e.g., less than 20 wt. % prime aluminum). Additionally, the aluminum alloys described herein allows for easier recycled aluminum alloy scrap management and provides a low carbon footprint for end users.

[0037] The aluminum alloy compositions described herein provide a combination of good mechanical properties, low prime content, to replace existing high strength 6xxx series aluminum alloys. The aluminum alloy can be produced from a minimum of 80 wt. % recycled aluminum alloy materials. In some embodiments, the aluminum alloy described herein includes 0.2 to 0.5 wt. % Fe and 0.05 to 0.5 wt. % Mn, along with a balance of Si, Mg, and Cu such that age hardening of the aluminum alloy is dominated by Mg2Si, quaternary Q, and / or AhCuMg second phase particles. Accordingly, the alloys described herein are designed to absorb a variety of recycled aluminum alloy scrap sources including 3xxx series recycled aluminum alloy scrap, 5xxx series recycled aluminum alloy scrap, 6xxx series recycled aluminum alloy scrap, mixed end-of-life (“EOL”) aluminum alloy scrap, can body stock (CBS) run around (RAR) scrap, Twitch, mixed 5xxx and 6xxx series aluminum alloy shred scrap, or a combination thereof.Definitions and Descriptions

[0038] 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.

[0039] In this description, reference is made to alloys identified by aluminum industry designations, such as “series” or “6xxx.” 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.

[0040] As used herein, the meaning of “a,” “an,” or “the” includes singular and plural references unless the context clearly dictates otherwise.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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 alloycooled 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.

[0046] 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.

[0047] 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.

[0048] 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

[0049] Aluminum alloy properties are partially determined 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.

[0050] Described herein are novel 6xxx series aluminum alloys. The properties of the aluminum alloys are achieved due to the compositions and / or methods of making the alloys.

[0051] In some examples, an aluminum alloy as described herein can have the following elemental composition as provided in Table 1.Table 1

[0052] In some examples, the aluminum alloy as described herein can have the following elemental composition as provided in Table 2.Table 2

[0053] In some examples, the aluminum alloy as described herein can have the following elemental composition as provided in Table 3.Table 3

[0054] In some examples, the aluminum alloy can have the following elemental composition as provided in Table 4.Table 4

[0055] It is to be understood that, in various embodiments of the alloys described herein, including those in Tables 1-4, the predominant element is aluminum (Al), sometimes called“remainder Al.” In other words, the term “remainder” can be used to describe predominant aluminum (Al) content in the aluminum alloys described herein.Silicon (Si)

[0056] In some examples, the aluminum alloy described herein includes Si in an amount of from 0.30 % to 0.80 % (e.g., from 0.30 % to 0.50 %, from 0.40 % to 0.80 %, from 0.50 % to 0.80 %, from 0.50 % to 0.70 %, or from 0.60 % to 0.80 %) based on the total weight of the alloy. For example, the alloy can include 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 %Si. All expressed in wt. %.Iron (Fe)

[0057] In some examples, the aluminum alloy described herein also includes Fe in an amount of from 0.20 % to 0.50 % (e.g., from 0.20 % to 0.40 %, from 0.20 % to 0.30 %, or from 0.25 % to 0.35 %) based on the total weight of the alloy. For example, the alloy can include 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 %, or 0.50 % Fe. All expressed in wt. %.Copper (Cu)

[0058] In some examples, the aluminum alloy described herein includes Cu in an amount of from 0.10 % to 0.60 % (e.g., from 0.15 % to 0.50 %, from 0.20 % to 0.50 %, or from 0.30 % to 0.50 %) based on the total weight of the alloy. For example, the alloy can include 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)

[0059] In some examples, the aluminum alloy described herein can include Mn in an amount from 0.05 % to 0.50 % (e.g., from 0.05 % to 0.40 %, from 0.05 % to 0.20 %, or from 0.20 % to 0.40 %) based on the total weight of the alloy. For example, the alloy can include0.05 %, 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 %, or 0.40 % Mn. All expressed in wt. %.Magnesium (Mg)

[0060] In some examples, the aluminum alloy described herein can include Mg in an amount from 0.80 % to 2.00 % (e.g., from 0.80 % to 1.60 %, from 0.85 % to 1.10 %, or from 1.40 % to 1.60 %) 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 %, 1.28 %, 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 %, 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 %, 1.89 %, 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. %. The aluminum alloys described herein are excess Mg aluminum alloys. In other words, the aluminum alloys include amounts of Mg content in excess of the amount required to form stochiometric Mg2Si. Without being bound by theory, excess Mg contributes to the amount of insoluble Mg2Si phase particles present in the aluminum alloy following solution heat treatment, and hardening can be achieved by precipitation of AhCuMg / Q and / or Mg2Si / Q phase particles. In some embodiments, a weight ratio of the Mg content to Si content is from greater than 1 : 1 to 5: 1 (e.g., 2: 1, 3: 1, or 4: 1). In some aspects, the weight ratio of Mg content to Si content is from 1.8 to 4.9 (e.g., 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6,2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7,4.8, or 4.9). In some embodiments, the Mg2Si phase particles are present in the alloy in an amount of up to 3 wt.% (e.g., up to 1 wt. %, up to 2 wt. %, or up to 3 wt. %). In some aspects, the Mg2Si phase particles are present in the alloy in an amount of 0.8 wt. % to 3.0 wt. % (e.g., 0.9 wt. % to 2.9 wt. %, 1.1 wt. % to 2.8 wt. %, 1.3 wt. % to 2.7 wt. %, 1.4 wt. % to 3.0 wt. %, 1.5 wt. % to 2.6 wt. %, or 1.7 wt. % to 2.5 wt. %). In some aspects, a weight ratio of a-Al(FeMn)Si phase particles to Mg2Si phase particles is from 4: 1 to 9: 1. In some aspects, a weight ratio of a-Al(FeMn)Si phase particles to Mg2Si phase particles is 9: 1 or greater.Zinc (Zn)

[0061] In some examples, the aluminum alloy described herein includes Zn in an amount of up to 0.15 % (e.g., up to 0.12, up to 0.09 %, up to 0.07 %, up to 0.05 %, up to 0.03 %, or from 0.01 % to 0.05 %) 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 %, or 0.15 % Zn. In some cases, Zn is not present in the alloy (i.e., 0 %). All expressed in wt. %.Titanium (Ti)

[0062] In some examples, the aluminum alloy described herein includes Ti in an amount up to 0.15 % (e.g., up to 0.12 %, up to 0.09 %, up to 0.07 %, up to 0.05 %, up to 0.03 %, or from 0.01 % to 0.05 %) 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 %, or 0.15 % Ti. In some cases, Ti is not present in the alloy (i.e., 0 %). All expressed in wt. %.Chromium (Cr)

[0063] In some examples, the aluminum alloy described herein includes Cr in an amount of up to 0.20 % (e.g., up to 0. 15 %, up to 0.12 %, 0.09 %, up to 0.07 %, up to 0.05 %, up to 0.03 %, or from 0.01 % to 0.05 %) 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 %, or 0.20 % Cr. In some cases, Cr is not present in the alloy (i.e., 0 %). All expressed in wt. %.Minor Elements

[0064] 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 Ti, Sc, V, Ni, Hf, Zr, Sn, Ga, Ca, Bi, Na, Pb, Sr, B, C or combinations thereof. Accordingly, Ti, Sc, V, Ni, Hf, Zr, Sn, Ga, Ca, Bi, Na, Pb, Sr, B, or C 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., 0.1 %). All expressed in wt. %. The remaining percentage of each alloy can be aluminum.Properties

[0065] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have a yield strength of 100 Mpa or greater when in a T4 temper. For example, an aluminum alloy product produced from the aluminum alloys described herein can have a yield strength of 110 Mpa or greater, 120 Mpa or greater, 130 Mpa or greater, or 140 Mpa or greater, when in a T4 temper. In some cases, the yield strength is from 100 Mpa to 140 Mpa (e.g., from 110 Mpa to 140 Mpa, from 120 Mpa to 140 Mpa, or from 130 Mpa to 140 Mpa), or anywhere in between, when in a T4 temper. 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.

[0066] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have an ultimate tensile strength of about 200 Mpa or greater when in a T4 temper. For example, the aluminum alloy products can have an ultimate tensile strength of 210 Mpa or greater, 220 Mpa or greater, 230 Mpa or greater, 240 Mpa or greater, 250 Mpa or greater, 255 Mpa or greater, 260 Mpa or greater, 265 or greater, 270 or greater, 275 or greater, or 280 or greater, when in a T4 temper. In some cases, the ultimate tensile strength is from 200 Mpa to 300 Mpa (e.g., from 210 Mpa to 300 Mpa, from 215 Mpa to 280 Mpa, or from 220 Mpa to 280 Mpa), or anywhere in between, when in a T4 temper. 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.

[0067] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have a total elongation of 15% or greater when in a T4 temper. For example, an aluminum alloy product produced from the aluminum alloys described herein can have a total elongation of 16% or greater, 17% or greater, 18% or greater, 19% or greater, 20% or greater, 21% or greater, 22% or greater, 23% or greater, 24% or greater, 25% or greater, 26% or greater, 28% or greater, or 29% or greater when in a T4 temper. In some cases, the total elongation is from 20% to 30% (e.g., from 20% to 30%, from 21% to 30%, from 22% to 30%, 23% to 30%, 24% to 30%, or from 25% to 23%), or anywhere in between, when in a T4 temper. The aluminum alloy products described herein can exhibit the total elongation 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.

[0068] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have a uniform elongation of 20% or greater when in a T4 temper. For example, an aluminum alloy product produced from the aluminum alloys described herein can have a uniform elongation of 18% or greater, 19% or greater, 20% or greater, 21% or greater, 22% or greater, 23% or greater, or 24% or greater, when in a T4 temper. In some cases, the uniform elongation is from 18% to 28% (e.g., from 19% to 28%, from 20% to 28%, from 21% to 28%, from 22% to 28%, from 23% to 26%, or from 23% to 25%), or anywhere in between, when in a T4 temper. The aluminum alloy products described herein can exhibit the uniform elongation 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.

[0069] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have a bend angle as measured according to the test set forth in Verband der Automobilindustrie (VDA) Test No. 238-100 from 90 ° to 145 ° when in a T4 temper and subjected to 10 % prestrain (e.g., from 90 ° to 140 °, from 90 ° to 130 °, or from 90 ° to 120 °). For example, an aluminum alloy product produced from the aluminum alloys described herein can have a VDA bending angle of about 90 °, 95 °, 100 °, 105 °, 110 °, 115 °, 120 °, 125 °, 130 °, 135 °, 140 °, or 145 °, when in a T4 temper and subjected to 10 % prestrain, or anywhere in between.

[0070] 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 200 Mpa or greater when in a T8x temper. For example, an aluminum alloy product produced from the aluminum alloys described herein can have a yield strength of 220 Mpa or greater, 230 Mpa or greater, 240 Mpa or greater, 250 Mpa or greater, 260 Mpa or greater, 270 Mpa or greater, or 280 Mpa or greater when in a T8x temper. In some cases, the yield strength is from 200 Mpa to 300 Mpa (e.g., from 200 Mpa to 280 Mpa, from 220 Mpa to 290 Mpa, from 240 Mpa to 280 Mpa, or from 250 Mpa to 275 Mpa), or anywhere in between, when in a T8x temper. 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.

[0071] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have an ultimate tensile strength of about 280 Mpa or greater when in a T8x temper. For example, the aluminum alloy products can have an ultimate tensile strength of 290 Mpa or greater, 300 Mpa or greater, 310 Mpa or greater, 320 Mpa or greater, or 330Mpa or greater when in a T8x temper. In some cases, the ultimate tensile strength is from 280 Mpa to 340 Mpa (e.g., from 290 Mpa to 335 Mpa, from 295 Mpa to 330 Mpa, or from 300 Mpa to 325 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.

[0072] In some examples, an aluminum alloy product produced from the aluminum alloys described herein can have a total elongation of 6% or greater when in a T8x temper. For example, an aluminum alloy product produced from the aluminum alloys described herein can have a total elongation of 7% or greater, 8% or greater, or 9% or greater, when in a T8x temper. In some cases, the total elongation is from 6% to 24% (e.g., from 7% to 23%, from 8% to 22%, from 9% to 21%, from 10% to 20%, from 11% to 19%, from 12% to 18%, or from 13% to 17%), or anywhere in between, when in a T8x temper. The aluminum alloy products described herein can exhibit the total elongation 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

[0073] The aluminum alloys described herein can be cast into a cast product using a direct chill (DC) process or can 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. 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. In some examples, the casting process is a DC casting process to form a cast product.

[0074] The cast product, slab, or strip 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 continuous annealing and solution heat treatment (SHT) 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.

[0075] In a homogenization step, a cast product may be heated to a homogenization temperature, such as a temperature from 500 °C to 580 °C (e.g., from 500 °C to 580 °C, from540 °C to 580 °C, from 550 °C to 575 °C, from 560 °C to 570 °C,). For example, the cast product can be heated to a temperature of 500 °C, 510 °C, 520 °C, 530 °C, 540 °C, 550 °C, 560 °C, 570 °C, and 580 °C. In some embodiments, the homogenization temperature is greater than 550 °C. The cast product may then be allowed to soak (i.e., held at the indicated temperature) for a period of time to form a homogenized product. In some examples, the total time for the homogenization step, including the heating and soaking phases, can be up to 10 hours. In some examples, the total time for the homogenization step, including the heating and soaking phases, can be up to 48 hours.

[0076] Following a homogenization step, a hot rolling step can be performed. In some embodiments, the homogenized product is hot rolled directly after homogenization. The entry temperature to the hot rolling step can be the same as the homogenization temperature. In some embodiments, the entry temperature prior to hot rolling is close to the homogenization temperature (e.g., between 500 °C and 580 °C). In some embodiments, the homogenized product can be cooled prior to the start of hot rolling. The homogenized product can be hot rolled using a rolling mill to produce a hot rolled product. The homogenized product can be hot rolled at a hot rolling temperature ranging from 400 °C to 580 °C (e.g., from 410 °C to 590 °C, from 420 °C to 580 °C, from 430 °C to 570 °C, from 440 °C to 560 °C, from 450 °C to 550 °C, from 460 °C to 560 °C, from 530 °C to 555 °C, or from 530 °C to 550 °C). For example, the homogenized product can be hot rolled at a hot rolling 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, or 580 °C.

[0077] The hot rolled product can be cold rolled using cold rolling mills into thinner products, such as a final gauge rolled product. The final gauge rolled product can have a gauge between 0.5 to 10 mm, e.g., between 0.7 to 6.5 mm. Optionally, the final gauge rolled product can have a gauge of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm. The cold rolling can be performed to result in a final gauge thickness that represents a gauge reduction of up to 85 % (e.g., up to 10 %, up to 20 %, up to 30 %, up to 40 %, up to 50 %, up to 60 %, up to 70 %, up to 80 %, or up to 85 % reduction) as compared to a gauge prior to the start of cold rolling. In some embodiments, the cold rolling step may include one or more cold rolling steps to achieve the desired gauge thickness reduction. Optionally, the process for producing the aluminum alloy can include an interannealing step (e.g., between one or more cold rolling steps).

[0078] Following hot rolling or cold rolling, the final gauge rolled product can be solution heat treated. For example, the final gauge rolled product can be heated to a peak metal temperature for solution heat treatment (directly) after cold rolling. The solution heat treatment step may include heating the final gauge rolled product from room temperature to a peak metal temperature of from 400° C to 580° C (e.g., from 420° C to 580° C, from 440° C to 570° C, from 450° C to 570° C, from 460° C to 570° C, from 470° C to 570° C, from 480° C to 570° C, or from 500° C to 570° C). The final gauge rolled product can soak at the peak metal temperature for a period of time. In certain aspects, the final gauge rolled product is allowed to soak for up to approximately 1 minute (e.g., from 0 seconds to 60 seconds inclusively) at the peak metal temperature. For example, the final gauge rolled product can be soaked at the peak metal temperature from 500° C to 550° C for 0 seconds, 5 seconds, 10 seconds, 15 seconds, 20 seconds, 25 seconds, 30 seconds, 35 seconds, 40 seconds, 45 seconds, 50 seconds, 55 seconds, 60 seconds, or anywhere in between. In some embodiments, the solution heat treatment step comprises soaking the final gauge rolled product for 0 seconds to 30 seconds at a peak metal temperature between 515° C to 560° C. In some embodiments, the final gauge rolled product includes Q phase particles prior to solution heat treatment, and subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves the Q phase particles and the final gauge rolled product contains less than 1 wt. % Q phase particles after the solution heat treatment. In some aspects, the final gauge rolled product includes Fe-containing particles such as a-Al(Fe,Mn,Cu) Si, Q, and Mg2Si phase particles before solution heat treatment and contains no Q phase and / or Mg2Si particles after solution heat treatment. In some embodiments, the final gauge rolled product includes AhCuMg phase particles prior to solution heat treatment, and subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves the AhCuMg phase particles and the final gauge rolled product contains less than 1 wt. % of AhCuMg phase particles after the solution heat treatment. In some embodiments, the final gauge rolled product includes Mg2Si phase particles prior to solution heat treatment, and subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves a majority of the Mg2Si phase particles and the final gauge rolled product contains up to 3 wt. % of Mg2Si phase particles after the solution heat treatment. In some embodiments, the final gauge rolled product includes Mg2Si phase particles prior to solution heat treatment, and subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves a majority ofthe Mg2Si phase particles and the final gauge rolled product contains from 0.8 wt. % to 3.0 wt. % Mg2Si phase particles after the solution heat treatment.

[0079] In certain aspects, the final gauge rolled product is air cooled or quenched after heat treatment. For example, the final gauge rolled product can be quenched directly after soaking at the peak metal temperature in the solution heat treatment step. The aluminum alloy can be quenched with air or water. In some embodiments, the quenching rate is from 5 °K / s to 200 °K / s.

[0080] In certain aspects, the final gauge rolled aged to a temper. The final gauge rolled product can be naturally aged or artificially aged for a period of time to result in T temper. For example, the final gauge rolled product can be aged to T4 temper, a T6 temper, or a T81 temper. In certain aspects, the final gauge rolled product provided in the T6 temper can be artificially aged (AA) at 160° C to 250° C (e.g., 160° C, 165° C, 170° C, 175° C, 180° C, 185° C, 190° C, 195° C, 200° C, 205° C, 210° C, 215° C, 220° C, 225° C, 230° C, 235° C, 240° C, 245° C, or 250° C) for a period of time. Optionally, the final gauge rolled product can be artificially aged for a period from 15 minutes to 8 hours (e.g., 15 minutes, 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, or 8 hours or anywhere in between) to result in the T6 temper or T7 temper.

[0081] The aluminum alloy described herein is suitable for use in the manufacturing of products formed by plastic forming processes such as creep forming, roll forming, and stretch forming. For example, the aluminum alloy described herein can produce a roll formed product. The aluminum alloy described herein is particularly useful in roll forming applications where an aluminum alloy sheet is subjected to continuous bending operations through a consecutive set of rolls to produce a roll formed product.Recycled Content Alloys

[0082] The aluminum alloys described herein can be produced from a substantial portion of recycled aluminum alloy scrap. In some embodiments, the aluminum alloys described herein can be produced from a combination of different recycled aluminum alloy scrap materials. Recycled aluminum alloy scrap (e.g., recycled scrap) can be obtained from various sources at all stages of the aluminum life cycle. In some cases, recycled aluminum alloy scrap can refer to a collection of recycled metal. Recycled aluminum alloy scrap can include materials recycled from any suitable source, such as from a metal production facility (e.g., a metal casting facility), from a metalworking facility (e.g., a production facility that uses metal products to create consumable products), or from post-consumer sources (e.g., regionalrecycling facilities). For example, internal scrap may be produced during production of an aluminum alloy in a metal casting facility (e.g., scrap from producing an aluminum ingot, billet, sheet, plate, etc.), customer scrap may be produced during stamping, milling, and other processes in a metalworking facility (e.g., scrap from creating can bodies, can ends, automobile parts, etc.), and post-consumer scrap may be produced from aluminum products used by consumers and collected at regional recycling facilities (e.g., used beverage cans, used automobile parts, etc.). Each of these types of recycled aluminum alloy scrap can be a substitute for primary aluminum.

[0083] The aluminum alloys described herein can tolerate high 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 specific aluminum alloy composition to compensate for the impurities. This enables a higher amount of less expensive, higher impurity aluminum scrap for producing aluminum alloys that can still exhibit desirable properties.

[0084] In some aspects, the aluminum alloy can be produced from up to 100 wt. wt. % recycled aluminum alloy scrap (e.g., from 70 wt. % to 100 wt. %, from 75 wt. % to 100 wt. %, from 80 wt. % to 100 wt. %, or from 90 wt. % to 100 wt. %), based on the total weight of the aluminum alloy. In some examples, the aluminum alloy can be produced from 3xxx series recycled aluminum alloy scrap, 5xxx series recycled aluminum alloy scrap, 6xxx series recycled aluminum alloy scrap, mixed end-of-life (“EOL”) aluminum alloy scrap, or a combination thereof. In some aspects, 3xxx series recycled aluminum alloy scrap, 5xxx series recycled aluminum alloy scrap, 6xxx series recycled aluminum alloy scrap, and / or mixed EOL recycled aluminum alloy scrap can have the following elemental composition (in weight percent) as provided in Table 5.

[0085] In some embodiments, the aluminum alloy can be produced from up to 20 wt. % of 3xxx series recycled aluminum alloy scrap (e.g., up to 5 wt. %, up to 10 wt. %, or up to 15 wt. %). All are expressed in wt. wt. %. In some embodiments, the aluminum alloy can be produced from up to 40 wt. % of 5xxx series recycled aluminum alloy scrap (e.g, up to 10 wt. %, up to 20 wt. %, or up to 30 wt. %). All are expressed in wt. wt. %. In some embodiments, the aluminum alloy can be produced from up to 80 wt. % 6xxx series aluminum alloy scrap (e.g., up to 25 wt. %, up to 50 wt. %, up to 70 wt. %, or up to 75 wt. %). All are expressed in wt. wt. %. In some embodiments, the aluminum alloy can be produced from up to 35 wt. % mixed EOL recycled aluminum alloy scrap (e.g., up to 5 wt. %, up to 10 wt. %, up to 15 wt. %, up to 20 wt. %, up to 25 wt. %, or up to 30 wt. %).

[0086] In some embodiments, the aluminum alloy can be produced from up to 25 wt. % segregated Twitch recycled aluminum alloy scrap (e.g., up to 15 wt. % or up to 20 wt. %). For example, the aluminum alloy can be produced from 5 wt. % to 30 wt. % segregated Twitch (e.g., from 5 wt. % to 25 wt. %, from 10 wt. % to 25 wt. %, from 15 wt. % to 25 wt. %, or from 20 wt. % to 30 wt. %).

[0087] In some embodiments, the aluminum alloy can be produced from up to 25 wt. % mixed 5xxx / 6xxx series aluminum alloy shred recycled scrap (e.g., up to 15 wt. % or up to 20 wt. %). For example, the aluminum alloy can be produced from 5 wt. % to 25 wt. % mixed 5xxx / 6xxx series aluminum alloy shred recycled scrap (e.g., from 5 wt. % to 25 wt. %, from 10 wt. % to 25 wt. %, from 15 wt. % to 25 wt. %, or from 20 wt. % to 25 wt. %).

[0088] In some embodiments, the aluminum alloy can be produced from up to 15 wt. % can body stock (CBS) run around (RAR) recycled aluminum alloy scrap (e.g., up to 5 wt. % or up to 10 wt. %). For example, the aluminum alloy can be produced from 5 wt. % to 25 wt. % CB) run (RAR) recycled aluminum alloy scrap (e.g., from 1 wt. % to 15 wt. %, from 5 wt. % to 15 wt. %, from 10 wt. % to 15 wt. %, or from 0 wt. % to 10 wt. %).

[0089] In some embodiments, prime aluminum can be used in combination with the recycled aluminum alloy scrap to produce the aluminum alloys described herein. For example, up to 20 wt. % prime aluminum (e.g., up to 18 wt. %, up to 15 wt. %, up to 12 wt. %, up to 10 wt. %, up to 8 wt. %, up to 6 wt. %, up to 4 wt. %, up to 2 wt. %, or up to 1 wt. %) can be used to produce the aluminum alloys described herein. All are expressed in wt. wt. %. In some embodiments, no prime aluminum alloy is used with the recycled aluminum alloy scrap.Illustrations of Suitable Methods and Alloy Products

[0090] Illustration 1 is an aluminum alloy comprising 0.30 - 0.80 wt. % Si, 0.20 - 0.50 wt. % Fe, 0.10 - 0.60 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 2.00 wt. % Mg, up to 0.20 wt. % Cr, up to 0.20 wt. % Zn, up to 0.15 wt. % Ti, up to 0.15 wt. % of impurities, and Al, wherein the aluminum alloy comprises less than 20 wt.% prime aluminum; and wherein the aluminum alloy comprises Mg2Si phase particles that are present in an amount from 0.8 wt. % to 3.0 wt. %.

[0091] Illustration 2 is the aluminum alloy of any preceding or subsequent illustration, comprising 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.85 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.

[0092] Illustration 3 is the aluminum alloy of any preceding or subsequent illustration, comprising 0.30 - 0.50 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.05 - 0.20 wt. % Mn, 1.4 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.

[0093] Illustration 4 is the aluminum alloy of any preceding or subsequent illustration, comprising 0.50 - 0.70 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.20 - 0.40 wt. % Mn, 0.85 - 1.10 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.

[0094] Illustration 5 is the aluminum alloy of any preceding or subsequent illustration, comprising recycled aluminum alloy scrap, wherein the recycled aluminum alloy scrap comprises one or more of up to 15 wt. % 3xxx series recycled aluminum alloy scrap, up to 30 wt. % 5xxx series recycled aluminum alloy scrap, up to 70 wt. % 6xxx series recycled aluminum alloy scrap, or up to 30 wt. % mixed EOL aluminum alloy scrap.

[0095] Illustration 6 is the aluminum alloy of any preceding or subsequent illustration, comprising soluble Q phase particles, wherein after solution heat treating the aluminum alloy, the aluminum alloy comprises less than 1 wt. % of Q phase particles.

[0096] Illustration 7 is the aluminum alloy of any preceding or subsequent illustration, wherein a ratio of a-Al(FeMn)Si phase particles to Mg2Si phase particles is 9: 1 or greater.

[0097] Illustration 8 is the aluminum alloy of any preceding or subsequent illustration, wherein the total amount of Fe, Mn, and Cr is at least 0.5 wt. %.

[0098] Illustration 9 is the aluminum alloy of any preceding or subsequent illustration, wherein the aluminum alloy has a yield strength of 220 MPa to 300 MPa in a T8x temper.

[0099] Illustration 10 is the aluminum alloy of any preceding or subsequent illustration, wherein the aluminum alloy is pre-strained.

[0100] Illustration 11 is the aluminum alloy of any preceding or subsequent illustration, wherein the aluminum alloy is in a T4 temper, a T6 temper, or a T8x temper.

[0101] Illustration 12 is the aluminum alloy of any preceding or subsequent illustration, wherein the aluminum alloy is strained from 0.25% to 30%, and the aluminum alloy is substantially free from Type A Luder lines.

[0102] Illustration 13 is the aluminum alloy of any preceding or subsequent illustration, wherein the aluminum alloy exhibits an increase in yield strength from 170 MPa to 270 MPa after a paint bake cycle at a temperature from 140 °C to 180 °C for 10 to 30 minutes.

[0103] Illustration 14 is a method of producing an aluminum alloy comprising casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al, wherein the aluminum alloy comprises less than 20 wt.% prime aluminum; homogenizing the cast product; hot rolling the cast product to produce a hot rolled product; cold rolling the rolled product to produce a final gauge rolled product; and solution heat treating the final gauge rolled product.

[0104] Illustration 15 is the method of any preceding or subsequent illustration, further comprising aging the final gauge rolled product to a T temper.

[0105] Illustration 16 is the method of any preceding or subsequent illustration, wherein the T temper is a T4 temper, a T6 temper, or a T8x temper.

[0106] Illustration 17 is the method of any preceding or subsequent illustration, further comprising pre-straining the final gauge rolled product after ageing.

[0107] Illustration 18 is the method of any preceding or subsequent illustration, wherein the cast product is cast from an aluminum alloy comprising one or more of Twitch, 5xxx aluminum alloys, 6xxx aluminum alloys, or can body stock.

[0108] Illustration 19 is the method of any preceding or subsequent illustration, wherein the final gauge rolled product comprises Q phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves the Q phase particles and the final gauge rolled product is substantially free of Q phase particles after the solution heat treatment.

[0109] Illustration 20 is the method of any preceding or subsequent illustration, wherein the final gauge rolled product comprises Mg2Si phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 600 °C for 5 minutes to 30 minutes dissolves at least half of the Mg2Si phase particles and the final gauge rolled product comprises from 0.8 wt. % to 3 wt. % Mg2Si phase particles after the solution heat treatment.EXAMPLESExample 1

[0110] The aluminum alloy described herein can be prepared from mixed 5xxx / 6xxx series aluminum alloy scrap and other recycled aluminum alloy scrap sources containing higher amounts of alloying elements (Fe, Mn, Cr, and Zn) together with Mg compared to the conventional AA6014, AA6111 and AA6451 aluminum alloys. Exemplary compositions of the aluminum alloy described herein are listed in Table 6.*A11 expressed in wt. %.[OHl] The aluminum alloy composition of Example Alloys A and B are tailored to be produced from a variety of recycled aluminum alloy scraps including 3xxx series recycled aluminum alloy scrap, 5xxx series recycled aluminum alloy scrap, 6xxx series recycled aluminum alloy scrap, and / or mixed EOL recycled aluminum alloy scrap. Table 7 summarizes calculations to determine the recycled content of Example Alloy A and ExampleAlloy B in comparison AA5182. As can be seen from the calculations in Table 6, Example Alloy B can be produced from a wide range of recycled aluminum alloy scrap inputs totaling about 95 wt. % and 5 wt. % prime, while Example Alloy A can be produced from 75 wt. % to 80 wt. % recycled aluminum alloy scrap and 15 wt. % prime.Example 2

[0112] The recycled aluminum alloy scrap sources provided in Table 7 were melted to cast ingots for Example Alloys A and B having the composition provided in Table 5. One cast ingot was produced for Example Alloy A and two cast ingots were produced for Example Alloy B. The cast ingots for Example Alloys A and B were scalped and then homogenized in a two-step homogenization process. In the first step, the scalped ingots were heated to 560 °C and soaked for 19 hours. In the second step, the ingots were cooled to 540 °C, and then soaked for about 2 hours before the start of hot rolling from ingot to 4.5 mmgauge. The exit temperature of the ingots after hot rolling was 320 °C. The hot rolled products were coiled at the exit temperature of 320 °C. FIGS. 1A-1C and FIGS. 1D-1F show the reroll microstructures of Example Alloy A (FIG. 1A-1C) and Example Alloy B (FIG. 1D- 1F) across the reroll width at edge 1, center, and edge 2 locations. Both rerolls contain Mg2Si and Fe-containing particles of sizes up to 10 pm. Example Alloy A contains a greater number of particles compared to the Example Alloy B reroll. The large number of particles in Example Alloy A is consistent with its higher Mg content, which without being limited by theory, promotes the formation of insoluble Mg2Si particles.

[0113] Both rerolls of Example Alloy B and Example Alloy A were cold rolled in two passes to the final 0.9 mm gauge. The Example Alloy A coil was solution heat treated at 560 °C, rapidly cooled and coiled at a rewind temperature of 80 °C. The Example Alloy B coil was solution heat treated at two temperatures, first at 535 °C and then at 550°C, and coiled at a rewind temperature of 80 °C.

[0114] FIG. 2A-2B shows the as-polished microstructures of the Example Alloy A (FIG. 2A) and Example Alloy B (FIG.2B) sheet samples before solution heat treatment. FIG. 2C- 2D shows the as-polished microstructures of the Example Alloy A (FIG. 2C) and Example Alloy B (FIG. 2D) sheet samples after solution heat treatment. The cold rolled Example Alloy A sample before continuous annealing and solution heat treatment (SHT) exhibits coarser Mg2Si particles compared to its Example Alloy B counterpart and there is no change in the particle structures in the after SHT samples for both Example Alloy A and Example Alloy B, suggesting, without being limited by theory, that the particles observed before SHT are insoluble and remain unaffected after the SHT.

[0115] The particles in both before and after SHT were extracted from the matrix and analyzed using X-ray diffraction. FIG. 3A shows an X-ray diffraction plot of the before and after SHT samples of Example Alloy B. FIG. 3B shows an X-ray diffraction plot of the before and after SHT samples of Example Alloy A. In Example Alloy A, the before SHT sample contains a-AlFeSi, Q, AhCuMg and Mg2Si particles, while the after SHT sample shows only a-AlFeSi and Mg2Si particles. The Q phase diffraction lines are absent in the after SHT samples, demonstrating that Q and AhCuMg particles have dissolved in the matrix during solution heat treatment. The before SHT samples of Example Alloy B alloy contains a-Al(Fe, Mn, Cu) Si, Q, and Mg2Si particles while after SHT particle extract did not have Q phase particles.

[0116] The relative amounts of each phase in both before and after SHT samples of the Example Alloy A alloy is shown in FIG. 4A. The relative amounts of each phase in bothbefore and after SHT samples of the Example Alloy B alloy is shown in FIG. 4B. Overall, a- Al(Fe,Mn)Si particles are the most predominant phase in all samples. In Example Alloy A, the AECuMg and the Q phases were dissolved completely into the solid solution, and the fraction of Mg2Si was reduced. Most of the Mg2Si particles were insoluble because of the excess Mg in the Example Alloy A alloy. In the Example Alloy B alloy, all the fine Q phase and Mg2Si particles were dissolved during solution heat treatment and only nearly spherical coarse Mg2Si and Fe,Mn containing particles remained in the matrix.

[0117] Based on particle analysis, both Example Alloy A and Example Alloy B alloys contain large amounts of Fe and Mn containing particles and dispersoids, while hardening can be achieved by precipitation of AhCuMg / Q and Mg2Si / Q phases in the Example Alloy A and Example Alloy B, respectively.Example 3

[0118] The mechanical properties for Example Alloys A and B were further investigated. The ASTM tensile properties of Example Alloy A and Example Alloy B alloys and after 30 days of natural ageing, along with the ASTM tensile properties of AA5182 and AA6451 coils are summarized in Table 8. In Table 8, YS represents yield strength, UTS represents ultimate tensile strength, El (U) represents the uniform elongation, El (T) represents tensile elongation, and n( 10-20%) represents the strain-hardening exponent at 10-20% strain.

[0119] The Rio values in all samples and directions of both Example Alloy A and Example Alloy B alloys are comparable to those of AA5182, while R45 values are surprisingly higher than conventional X621 inner alloy.

[0120] FIG. 5 A shows the engineering stress strain curves of sheets cast from AA5182 in longitudinal, transverse, and diagonal directions, respectively. FIG. 5B shows the engineering stress strain curves of sheets cast from Example Alloy B in longitudinal, transverse, and diagonal directions, respectively. FIG. 5C shows the engineering stress strain curves of sheets cast from Example Alloy A in longitudinal, transverse, and diagonal directions, respectively. The alloy AA5182 exhibits undesirable Type A Ludering and serrations at higher strains which are not seen in the Example Alloy B and Example Alloy A curves. Example Alloy A exhibits serrations beyond 5% elongation. Generally, Example Alloy B tracks the AA5182 stress strain curve up to 10% and stays below the AA5182 curve thereafter.

[0121] FIG. 6 shows the natural ageing curve of Example Alloy A and Example Alloy B sheets solution heat treated at 550 °C and 535 °C. As expected, the yield strength (YS) of sheets solution heat treated at 550 °C is higher compared to sheets solution heat treated at 535 °C, although, without being limited by theory, the slopes of the two curves are similar suggesting that the rate of YS increase is consistent with slow natural ageing response and independent of the solutionizing temperature. Therefore, without being limited by theory, it is possible adjust the maximum YS depending on the choice of the solution heat treatment temperature without affecting ageing kinetics. The natural ageing of Example Alloy A is very slow and stable over long term of ageing.

[0122] The YS of a formed part is a cumulative result of the strength increase due to forming, precipitation hardening and the loss of strength due to strain recovery during the paint cure. The forming operation in the laboratory is simulated by 2% uniaxial strain which together with net YS increase due to precipitation hardening minus the strain energy loss is referred to herein as the paint bake response. The overall paint bake response depends on the paint cure temperature and increases with the paint cure temperature and time. FIG. 7A shows the YS of the Example Alloy B sheets (535 °C SHT) after ageing for 20 minutes at 140 °C, 160 °C and 180 °C. FIG. 7B shows the YS of the Example Alloy B sheets (550 °C SHT) after ageing for 20 minutes at 140 °C, 160 °C and 180 °C. FIG. 7C shows the YS of the Example Alloy A sheets (560 °C SHT) after ageing for 20 minutes at 140 °C, 160 °C and 180 °C. Unlike typical automotive 6xxx series products, Example Alloy B exhibits a paint bake response of 173 MPa at 140°C and exceeds 240 MPa for the coil solution heat treatedat 550°C and aged for 20 minutes at 180°C.

[0123] FIG. 8 A shows the elevated temperature ageing of Example Alloy B (535 °C SHT) at higher temperatures. FIG. 8B shows the elevated temperature ageing of the Example Alloy B alloy (550 °C SHT) at higher temperatures. FIG. 8C shows the elevated temperature ageing of Example Alloy A (560 °C SHT) at higher temperatures. The YS of Example Alloy B increases rapidly at elevated temperature ageing, which is beneficial for automotive skin applications, especially at 160 °C and 140 °C. Example Alloy A also exhibits rapid response but the extent of hardenability is less than the Example Alloy B variants.

[0124] Without being limited by theory, it is believed that the rapid ageing response of Alloy Example Alloy B at elevated temperatures is related to the precipitation of Q(AlCuMgSi) along with Mg2Si phase particles, as opposed to conventional 6xxx series alloys that are hardened by Mg2Si(Cu).

[0125] The ASTM tensile properties of two samples of each Example Alloy A and Example Alloy B in a T82 temper from inner diameter (ID) and outer diameter (OD) of the coils are summarized in Table 9. In Table 9, YS represents yield strength, UTS represents ultimate tensile strength, El (U) represents the uniform elongation, and El (T) represents tensile elongation.Example 4

[0126] To assess the formability of Example Alloy B, one coil of Example Alloy B was solution heat treated on the continuous heat treatment line (HTL), the first half at 550°C and the second half at 535°C. The longitudinal through thickness as polished and etched microstructures of Example Alloy B coil solution heat treated at 560°C is shown in FIG. 9A- 9B. The as-polished microstructure shows coarse (Fe,Mn)-containing and coarse undissolved Mg2Si particles in the matrix. The through thickness grain structure of the coil is finer than typical inner material, which, without being limited by theory, is related to the presence of alarge amount of constituent, undissolved Mg2Si and Mn bearing dispersoids in the microstructure.

[0127] The formability of the two variants of Example Alloy B solution heat treated at 535 °C and 550 °C were formed into the door inner panels using a stamping press. The blanks of the shape seen in FIG. 10A and re-lubed manually with DC290 before stamping. The die corners were also lubed with DC290 before stamping. The die is designed to produce stamping shown in FIG. 10B. There are four corners designed to study severity of forming. For example, comers 1 and 2 are typical radius for the door inners while 3 and 4 are extreme conditions in terms of radius, forming depth and associated strains.

[0128] Table 10 summarizes the stamping trial matrix used to evaluate the formability of Example Alloy B along with Example Alloy A and AA5182-0. Both variants of Example Alloy B formed all four comers of the stamping at 100 and 110 Bar binder pressures, successfully.

[0129] A forming trial using conditions listed in Table 10 was performed. The improved formability of the Example Alloys is believed to be related to insoluble particles which help to disperse the slip and improve formability.

[0130] To produce 1.5 mm gauge Example Alloy B coil with properties equivalent to AA5754-O, one coil was solution heat treated at two temperatures, the first half at 520 °C and the second half at 530 °C with a rewind temperature of 80 °C on the HTL. The coil was sampled on the pretreatment line and tested after 9 days of natural ageing. The tensile properties from both halves of the coil are listed in Tables 11 and the paint bake response in Table 12. Table 11 shows that the tensile properties of Example Alloy B at both are comparable to the 1.5 mm gauge AA5754-O production coil. In Table 11, YS represents yield strength, UTS represents ultimate tensile strength, El (U) represents the uniform elongation, El (T) represents tensile elongation, n( 10-20%) represents the strain-hardening exponent at 10-20% strain, R(10) represents the plastic strain ratio at 10% strain, and Average R(10) represents the plastic strain ratio in all directions at 10% strain.

[0131] Interestingly, Example Alloy B exhibits significant hardening response despite solution heat treatment at 520 °C and 530 °C, which can allow for downgauging.Example 5

[0132] Example Alloy C and Example Alloy D comprise the aluminum alloy compositions shown in Table 13. Each of Example Alloy C and Example Alloy D were cast to produce ingots, homogenized, and then hot rolled to produce coils having a gauge thickness of 4.5 mm. The hot rolled coils were cold rolled to a final gauge thickness of 1 mm and subjected to continuous annealing and solution heat treatment. Example Alloy D was solutionized at a temperature of about 560° C and coiled at a coiling temperature of about 80°C. Example Alloy C was solutionized at a temperature of about 525° C with and coiled at a coiling temperature of about 80° C at a line speed of 60 m / min. The solutionizing of Example Alloy C was about 25% faster than Example Alloy D. The solutionizing conditions for Example Alloys C and D were different to compare the T4 and paint bake properties (5% prestrain and heating at about 170° C for about 20 min). As shown in the Table 14 and 15, Example Alloy C exhibited mechanical properties that are within an acceptable range (e.g., + / - 5%) of Example Alloy D by properly selecting the solutionizing conditions.*A11 expressed in wt. %.

[0133] Table 14 provides the Japanese Industrial Standard (JIS) mechanical properties of Example Alloys C and D after 21 days of natural aging. In Table 14, YS represents yield strength, UTS represents ultimate tensile strength, El (U) represents the uniform elongation, El (T) represents tensile elongation, n(4-6%) represents the strain-hardening exponent at 4- 6% strain, n(10%) represents the strain-hardening exponent at 10% strain, and R(9-l l) represents the plastic strain ratio at 9-11% strain. The tensile test data in Table 14 shows that the YS, UTS, and elongation values of Example Alloy C are slightly lower than Example Alloy D, while other parameters like N and R values are quite similar.

[0134] Table 15 provides the mechanical properties of Example Alloys C and D after 21 days of natural ageing, 5% prestrain, and ageing at a temperature of about 170° C for about 20 minutes. In Table 15, YS represents yield strength, UTS represents ultimate tensile strength, and El (T) represents tensile elongation. Table 14 shows that the YS of Example Alloy C is equivalent to Example Alloy D despite lower YS after 21 days of ageing shown in Table 13. This data demonstrates that Example Alloy C is versatile enough to be used to provide a wide combination of properties while achieving higher solutionizing productivities and equivalent paint bake strength.

[0135] All patents, publications, and abstracts cited above are incorporated herein by reference in their entireties. Various embodiments of the invention have been described in fulfillment 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 0.30 - 0.80 wt. % Si, 0.20 - 0.50 wt. % Fe, 0.10 - 0.60 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 2.00 wt. % Mg, up to 0.20 wt. % Cr, up to 0.20 wt. % Zn, up to 0.15 wt. % Ti, up to 0.15 wt. % of impurities, and Al, wherein the aluminum alloy is produced from less than 20 wt.% prime aluminum; wherein the aluminum alloy comprises Mg2Si phase particles present in an amount from 0.8 wt. % to 3.0 wt. %; and wherein a weight ratio of the Mg content to Si content is greater than 1 : 1.

2. The aluminum alloy of claim 1, wherein the aluminum alloy comprises 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.85- 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.

3. The aluminum alloy of claim 1, wherein the aluminum alloy comprises 0.30 - 0.50 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.05 - 0.20 wt. % Mn, 1.4- 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.4 . The aluminum alloy of claim 1, wherein the aluminum alloy comprises 0.50 - 0.70 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.30 - 0.50 wt. % Cu, 0.20 - 0.40 wt. % Mn, 0.85- 1.10 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al.5 . The aluminum alloy of claim 1, wherein the aluminum alloy is produced from recycled aluminum alloy scrap, wherein the recycled aluminum alloy scrap comprises one or more of up to 15 wt. % 3xxx series recycled aluminum alloy scrap, up to 30 wt. % 5xxx series recycled aluminum alloy scrap, up to 70 wt. % 6xxx series recycled aluminum alloy scrap, or up to 30 wt. % mixed EOL aluminum alloy scrap.

6. The aluminum alloy of claim 1, wherein the aluminum alloy comprises soluble Q phase particles, wherein after solution heat treating the aluminum alloy, the aluminum alloy comprises less than 1 wt. % of Q phase particles.

7. The aluminum alloy of claim 1, wherein a ratio of a-Al(FeMn)Si phase particles to Mg2Si phase particles is 9: 1 or greater.

8. The aluminum alloy of claim 1, wherein a total amount of Fe, Mn, and Cr is at least 0.5 wt. %.

9. The aluminum alloy of claim 1, wherein the aluminum alloy has a yield strength of 220 MPa to 300 MPa in a T8x temper.

10. The aluminum alloy of claim 1, wherein the aluminum alloy is prestrained.

11. The aluminum alloy of claim 1, wherein the aluminum alloy is in a T4 temper, a T6 temper, or a T8x temper.

12. The aluminum alloy of claim 1, wherein the aluminum alloy is strained from 0.25% to 30%, and the aluminum alloy is substantially free from Type A Luder lines.

13. The aluminum alloy of claim 1, wherein the aluminum alloy exhibits an increase in yield strength from 170 MPa to 270 MPa after a paint bake cycle at a temperature from 140 °C to 180 °C for 10 to 30 minutes.

14. The aluminum alloy of claim 1, wherein the weight ratio of the Mg content to Si content is from 3: 1 to 5 : 1.

15. A method of producing an aluminum alloy comprising: casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises 0.30 - 0.80 wt. % Si, 0.20 - 0.40 wt. % Fe, 0.10 - 0.50 wt. % Cu, 0.05 - 0.50 wt. % Mn, 0.80 - 1.60 wt. % Mg, up to 0.10 wt. % Cr, up to 0.10 wt. % Zn, up to 0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al, wherein the aluminum alloy comprises less than 20 wt.% prime aluminum; homogenizing the cast product;hot rolling the cast product to produce a hot rolled product; cold rolling the hot rolled product to produce a final gauge rolled product; and solution heat treating the final gauge rolled product.

16. The method of claim 15, further comprising aging the final gauge rolled product to a T temper.

17. The method of claim 16, wherein the T temper is a T4 temper, a T6 temper, or a T8x temper.

18. The method of claims 15 or 16, further comprising pre-straining the final gauge rolled product after ageing.

19. The method of claim 15, wherein the cast product is cast from an aluminum alloy comprising one or more of Twitch, 5xxx aluminum alloys, 6xxx aluminum alloys, or can body stock.

20. The method of claim 15, wherein the final gauge rolled product comprises Q phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 580 °C for up to 1 minute dissolves the Q phase particles and the final gauge rolled product is substantially free of Q phase particles after the solution heat treatment.

21. The method of claim 15, wherein the final gauge rolled product comprises Mg2Si phase particles prior to solution heat treatment, and wherein subjecting the final gauge rolled product to solution heat treatment at a temperature from 500 °C to 600 °C for 5 minutes to 30 minutes dissolves at least half of the Mg2Si phase particles and the final gauge rolled product comprises from 0.8 wt. % to 3 wt. % Mg2Si phase particles after the solution heat treatment.

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