Aluminum alloy product with high formability in the o-temper and methods of producing the same

Abstract

Described herein are highly formable aluminum alloys with reduced stiffness and methods of producing such aluminum alloys. The methods described herein to prepare the aluminum alloys can use annealing and omit solution heat treatment or artificial aging to produce an aluminum alloy product exhibiting suitable stiffness and formability. The aluminum alloy products described herein are suitable for automotive applications. In particular, the aluminum alloy products described herein have reduced stiffness that beneficially reduce a likelihood or severity of pedestrian injury in an event of a collision between an automobile and a pedestrian. Additionally, the aluminum alloy products can have a lower magnesium content compared to conventional 5xxx series aluminum alloys used in automotive applications, which can reduce carbon emissions and energy consumption associated with producing the aluminum alloy products.

Description

Attorney Docket Number: 108050-1530450ALUMINUM ALLOY PRODUCT WITH HIGH FORMABILITY IN THEO-TEMPER AND METHODS OF PRODUCING THE SAMECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 743,799, filed January 10, 2025, which is hereby incorporated by reference in its entirety for all intents and purposes.FIELD

[0002] The present disclosure generally relates to aluminum alloys having high formability and related methods of producing the same. In particular, the present disclosure is related to metallurgy generally and more specifically to aluminum alloys with reduced stiffness and high formability and methods of producing the same.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 automotive 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. Even so, conventional processes of producing aluminum alloys for automotive applications poses certain challenges.

[0004] In particular, high strength 5xxx series and 6xxx series aluminum sheet alloys for automotive applications that are currently available typically lack suitable mechanical properties for pedestrian safety applications, such as in an event of a car colliding with a passerby. Injury or death of pedestrians can occur at least in part due to a front portion (e.g., a hood or windshield) of an automobile impacting a pedestrian at high velocity. In particular, pedestrian head injuries can occur as a result of hood stiffness and / or impact proximity to stiff understructures. In order to improve pedestrian safety of automotive applications, thereis a need for production processes that can produce 5xxx series or 6xxx series aluminum alloy products with suitable stiffness while maintaining other suitable mechanical properties (e.g., formability) for automotive applications.SUMMARY

[0005] The term embodiment and like terms are intended to refer broadly to all of the subject matter of this disclosure 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 claims below. Embodiments of the present disclosure covered herein are defined by the claims below, not this summary. This summary is a high-level overview of various aspects of the disclosure 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 of this disclosure, any or all drawings and each claim.

[0006] In an aspect, methods of producing an aluminum alloy product are described herein. In some embodiments, the method includes casting an aluminum alloy including a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof; hot rolling the aluminum alloy to produce a rolled aluminum alloy product; and processing the rolled aluminum alloy product according to one or more steps to provide the rolled aluminum alloy product in an O-temper. The one or more steps can include holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time; annealing the rolled aluminum alloy product; coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; or coiling the rolled aluminum alloy product at the hot rolling exit temperature. In some embodiments, the method can further include cold rolling the rolled aluminum alloy product. In some embodiments, the method does not include an artificial aging step. In some embodiments, the method does not include a solution heat treatment step. In some embodiments, further heat treatment is not applied after providing the rolled aluminum alloy product in the O-temper. In some embodiments, the aluminum alloy includes 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities.

[0007] In some embodiments, the rolled aluminum alloy product is a cold rolled aluminum alloy product having a thickness from 0.70 mm to 5.00 mm. In some embodiments, the hot rolling exit temperature ranges from 200 °C to 450 °C.

[0008] In some embodiments, the method includes one or more annealing steps. In some embodiments, the annealing step is performed immediately after the hot rolling step, during the cold rolling step (e.g., after one or more cold roll passes), and / or after cold rolling step. In some embodiments, the annealing step comprises self-annealing the rolled aluminum alloy product using the residual heat from the hot rolling step. In some embodiments, the annealing step is batch annealing the rolled aluminum alloy product at an annealing temperature ranging from 300 °C to 500 °C for 1 hour to 10 hours. In some embodiments, external heat is not supplied to process the rolled aluminum alloy product during coiling of the rolled aluminum alloy product using the residual heat corresponding to the hot rolling exit temperature.

[0009] In some embodiments, the aluminum alloy product exhibits a yield strength ranging from 25 MPa to 100 MPa. In some embodiments, the aluminum alloy product exhibits an ultimate tensile strength (UTS) ranging from 125 MPa to 200 MPa. In some embodiments, the aluminum alloy product exhibits an elongation ranging from 18 % to 26 %. In some embodiments, the aluminum alloy product exhibits a post-uniform elongation ranging from 4 % to 8 %. In some embodiments, a strain hardening value of the aluminum alloy product has a local maximum at a plastic strain of 0.015 to 0.05.

[0010] In another aspect, methods of producing an aluminum alloy product are described herein. In some embodiments, a method of this aspect includes casting an aluminum alloy including a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof, where the aluminum alloy comprises 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities; hot rolling the aluminum alloy to produce a rolled aluminum alloy product; and processing the rolled aluminum alloy product according to one or more steps to provide the rolled aluminum alloy product in an O-temper. In some embodiments, the steps can include holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time; annealing the rolled aluminum alloy product; coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; or coiling the rolled aluminum alloy product at the hot rolling exit temperature.

[0011] In yet another aspect, methods of producing an aluminum alloy product are described herein. In some embodiments, a method of this aspect includes casting an aluminum alloy including a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof; hot rolling the aluminum alloy to produce a hot rolled aluminum alloy product; optionally cold rolling the hot rolled aluminum alloy product to produce a cold rolled aluminum alloy product; and processing a rolled aluminum alloy product according to one or more steps to provide the rolled aluminum alloy product in an O-temper, where the rolled aluminum alloy product is the hot rolled aluminum alloy product or the cold rolled aluminum alloy product, where no solution heat treatment is performed to process the rolled aluminum alloy product. The steps can include holding the rolled aluminum alloy product at an exit temperature for a period of time, where the exit temperature is a hot rolling exit temperature of the hot rolling step or a cold rolling exit temperature of the cold rolling step; annealing the rolled aluminum alloy product; coiling the rolled aluminum alloy product using residual heat corresponding to the exit temperature; or coiling the rolled aluminum alloy product at the exit temperature. In some embodiments, the cold rolling exit temperature ranges from 80 °C to 160 °C.

[0012] In a further aspect, aluminum alloy products produced using the methods described herein are described herein. In some embodiments, the aluminum alloy products are used for automotive inner applications. In some embodiments, the aluminum alloy products are deep drawn parts.

[0013] Other objects and advantages will be apparent from the following detailed description of non-limiting examples.BRIEF DESCRIPTION OF THE FIGURES

[0014] The specification makes reference to the following appended figures, in which use of like reference numerals in different figures is intended to illustrate like or analogous components.

[0015] FIG. 1 provides a schematic overview of an example method for making a rolled aluminum alloy product.

[0016] FIG. 2 is a plot of measured yield strength (MPa) and ultimate tensile strength (MPa) versus calculated solid solution after batch annealing is applied to example 5xxx / 6xxx series aluminum alloys or 6xxx series aluminum alloys and comparative 5xxx series aluminum alloys.

[0017] FIG. 3 is a plot of uniform elongation (%) and post-uniform elongation (%) for example 5xxx / 6xxx series aluminum alloys or 6xxx series aluminum alloys and comparative 5xxx series aluminum alloys.

[0018] FIG. 4 is a plot of instantaneous n-values versus plastic strain (-) for an example alloy in O-temper and comparative alloys in O-temper and T4 temper.

[0019] FIG. 5 is a plot comparing instantaneous n-values versus plastic strain (-) for variations of an example alloy in an O-temper that have undergone or have forgone prestraining and paint bakingDETAILED DESCRIPTION

[0020] Described herein are aluminum alloy products with reduced stiffness that exhibit high formability and methods of producing the same. The methods described herein produce aluminum alloy products with high formability and suitable stiffness that can used in automotive parts. For example, the methods for producing aluminum alloy products described herein can be used to produce automotive components, such as an inner hood, having suitable post-uniform elongation enabling deformation without fracturing.Additionally, strain hardening properties of the aluminum alloy products described herein can result in aluminum alloy products that exhibit less rapid hardening compared to conventional 5xxx series or 6xxx series aluminum alloys. In other words, the mechanical properties of the aluminum alloy products described herein can cause a relatively low amount of hardening to occur during a potential deformation event, such as a pedestrian impact, thereby reducing a likelihood or severity of injury. Thus, the aluminum alloy products described herein can exhibit a lower stiffness compared to the conventional aluminum alloy products and be less likely to cause pedestrian injury upon impact. As used herein, “aluminum alloy product” refers to a sheet, a shate, or a plate. The aluminum alloy products described herein can be an extrusion, a rolled product (e.g., hot rolled product or cold rolled product), or a forged product.

[0021] As described herein, the methods produce aluminum alloy products with reduced stiffness and high formability properties that can be used as pedestrian-friendly parts in automotive applications. In particular, the methods can produce aluminum alloy products that exhibit less overall stiffness or less stiffness in distributed areas of the aluminum alloy products, thereby reducing a likelihood of pedestrian injury. Despite a decrease in stiffness, the aluminum alloy products described herein can exhibit similar or improved formability properties compared to the conventional aluminum alloys. Mechanical strength exhibited bythe aluminum alloy products described herein can fill a strength gap between conventional 5xxx series and 6xxx series aluminum alloys in automotive applications, where the conventional 6xxx series aluminum alloys typically have lower strength due to a lack of excess magnesium to drive strength and work hardening. Producing the aluminum alloy products using hybrid aluminum compositions associated with 5xxx series and 6xxx series aluminum alloy compositions can provide increased strength compared to conventional 6xxx series aluminum alloys used in skin or structural applications. Additionally, the methods described herein can produce aluminum alloy products in an O-temper using processing steps that forgo solution heat treatment and artificial aging. Accordingly, in contrast to aluminum alloy products produced using other tempers, the aluminum alloy products described herein can have a potentially unlimited shelflife due to its mechanical properties generally remaining consistent over time, such as when stored at room temperature.

[0022] Additionally, the methods described herein can beneficially reduce environmental impact, such as greenhouse gas emissions, associated with producing 5xxx series or 6xxx series aluminum alloy products. For instance, the methods can forgo solution heat treatment while achieving similar or better mechanical properties (e.g., with respect to formability, stiffness, elongation, etc.). Beneficially, the methods can omit solution heat treatment and artificial aging, which can reduce energy consumption and carbon emissions associated with heating the aluminum alloy product during these processing steps. In some embodiments, the methods described herein can involve having a rolling exit temperature high enough to anneal the aluminum alloy products such that a separate heating step is unnecessary, thereby further reducing costs and emissions.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 AA numbers and other related designations, such as “series” or “7xxx.” 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 AluminumAssociation 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, 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.

[0026] 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.

[0027] As used herein, a sheet generally refers to an aluminum product having a thickness of less than about 4 mm. For example, a sheet may have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, or less than about 0.3 mm (e.g., about 0.2 mm).

[0028] 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.

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

[0030] 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. As used herein, the meaning of “ambient conditions” can include temperatures of about room temperature, relative humidity of from about 20% to about 100%, and barometric pressure of from about 975 millibar (mbar) to about 1050 mbar. For example, relative humidity can be about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, 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%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%, or anywhere in between. For example, barometric pressure can be about 975 mbar, about 980 mbar, about 985 mbar, about 990 mbar, about 995 mbar, about 1000 mbar, about 1005 mbar, about 1010 mbar, about 1015 mbar, about 1020 mbar, about 1025 mbar, about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or anywhere in between.

[0031] All ranges disclosed herein are to be understood to encompass 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. Unless stated otherwise, the expression “up to” when referring to the compositional amount of an element means that element is optional and includes a zero percent composition of that particular element. Unless stated otherwise, all compositional percentages are in weight percent (wt.%).

[0032] As used herein, the meaning of “a,” “an,” and “the” includes singular and plural references unless the context clearly dictates otherwise.

[0033] In the following examples, aluminum alloy products and their components may be described in terms of their elemental composition in weight percent (wt.%). In each alloy, the remainder is aluminum, with a maximum wt.% of 0.15% for the sum of all impurities.

[0034] Incidental elements, such as grain refiners and deoxidizers, or other additives may be present in the invention and may add other characteristics on their own without departing from or significantly altering the alloy described herein or the characteristics of the alloy described herein.

[0035] Unavoidable impurities, including materials or elements may be present in an alloy in minor amounts due to inherent properties of aluminum or leaching from contact with processing equipment. Some alloys, as described, may contain no more than about 0.25 wt.% of any element besides the alloying elements, incidental elements, and unavoidable impurities.Alloy Compositions

[0036] Described below are aluminum alloy compositions for aluminum alloy products that can undergo one or more processing steps described herein for reduced stiffness and high formability properties. The properties of the alloys are achieved due in part to the composition of the alloys and in part to the methods of processing the alloys to produce the described products (e.g., plates, shates, and sheets). In some cases, the aluminum alloys described herein can include lower levels of Mg compared to conventional 5xxx series aluminum alloys. Reducing Mg content can beneficially reduce a carbon footprint associated with producing the aluminum alloy products described herein. In some examples, an aluminum alloy as described herein can have the following elemental composition as provided in Table 1.Table 1Silicon (Si)

[0037] In some examples, the aluminum alloy described herein includes Si in an amount of from 0.37 % to 1.25 % (e.g., from 0.37 % to 0.50 %, from 0.50 % to 1.00 %, from 1.00 % to 1.25 %, from 0.37 % to 1.25 %, from 0.50 % to 1.25 %, or from 1.00 % to 1.25 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 %, or 1.25 Si. All expressed in wt. %.Iron (Fe)

[0038] In some examples, the aluminum alloy described herein also includes Fe in an amount of from 0.20 % to 0.46 % (e.g., from 0.20 % to 0.46 %, from 0.30 % to 0.46 %, or from 0.25 % to 0.46 %) 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 %, or 0.46 % Fe. All expressed in wt. %.Copper (Cu)

[0039] In some examples, the aluminum alloy described herein includes Cu in an amount of from 0.10 % to 0.83 % (e.g., from 0.10 % to 0.20 %, from 0.10 % to 0.50 %, or from 0.50 % to 0.83 %) 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 %, 0.60 %, 0.61 %, 0.62 %, 0.63 %, 0.64 %, 0.65 %, 0.66 %, 0.67 %, 0.68 %, 0.69 %, 0.70 %, 0.71 %, 0.72 %, 0.73 %, 0.74 %, 0.75 %, 0.76 %, 0.77 %, 0.78 %, 0.79 %, 0.80 %, 0.81 %, 0.82 %, or 0.83 % Cu. All expressed in wt. %. Manganese (Mn)

[0040] In some examples, the aluminum alloy described herein can include Mn in an amount from 0.03 % to 0.40 % (e.g., from 0.03 % to 0.10 %, from 0.10 % to 0.20 %, from 0.20 % to 0.30 %, or from 0.30 % to 0.40 %) based on the total weight of the alloy. For example, the alloy can include 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 %, or 0.40 % Mn. All expressed in wt. %.Magnesium (Mg)

[0041] In some examples, the aluminum alloy described herein can include Mg in an amount from 0.31 % to 1.85 % (e.g., from 0.31 % to 0. 50 %, from 0.50 % to 1.00 %, from 1.00 % to 1.85 %, from 0.60 % to 1.20 %, or from 0.50 % to 1.85 %) based on the total weight of the alloy. For example, the alloy can include 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 %, 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 %, 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 %, or 1.85 % Mg. All expressed in wt. %. Chromium (Cr)

[0042] In some examples, the aluminum alloy described herein includes Cr in an amount from 0.01 % to 0.18 % (e.g., from 0.01 % to 0.05 %, from 0.01 % to 0.10 %, or from 0.10 % to 0.18 %) 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 %, or 0.18 % Cr. In some cases, Cr is not present in the alloy (i.e., 0 %). All expressed in wt. %.Minor Elements

[0043] Optionally, the aluminum alloys described herein can further include other minor elements, sometimes referred to as impurities, in amounts of 0.25 % or below, 0.24 % or below, 0.23 % or below, 0.22 % or below, 0.21 % or below, or 0.20 % or below. These impurities may include, but are not limited to Zn, Ti, V, Ni, Sc, Hf, Zr, Sn, Ga, Ca, Bi, Na, Pb, or combinations thereof. Accordingly, Zn, Ti, V, Ni, Sc, Hf, Zr, Sn, Ga, Ca, Bi, Na, or Pb may be present in alloys in amounts of 0.15 % or below, 0.10 % or below, 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 0.25 % (e.g., 0.20 %). All expressed in wt. %. The remaining percentage of each alloy can be aluminum.Methods of Producing the Alloys and Aluminum Alloy Products

[0044] The aluminum alloy products described herein can be prepared using suitable methods. For example, aluminum alloys may be cast, homogenized, hot-rolled, cold-rolled, annealed, coiled, formed, or the like to produce aluminum alloy products. In some embodiments, the methods described herein can produce aluminum alloy products in an O-temper. In certain aspects, the methods described herein can omit solution heat treatment or artificial aging steps.

[0045] In some embodiments the aluminum alloy products described herein include 5xxx series aluminum alloys, 6xxx series aluminum alloys, or a combination thereof. By way of non-limiting example, exemplary 5xxx series aluminum alloys for use in the methods described herein can include AA5182, AA5183, AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106, AA5010, AA5110, AA5110A, AA5210, AA5310,AA5016, AA5017, AA5018, AA5018A, AA5019, AA5019A, AA5119, AA5119A, AA5021, AA5022, AA5023, AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042, AA5043, AA5049, AA5149, AA5249, AA5349, AA5449, AA5449A, AA5050, AA5050A, AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA5254, AA5354, AA5454, AA5554, AA5654, AA5654A, AA5754, AA5854, AA5954, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA5070, AA5180, AA5180A, AA5082, AA5182, AA5083, AA5183, AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

[0046] Non-limiting exemplary 6xxx series aluminum alloys for use in the methods described herein can include AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, AA6205, AA6305, AA6006, AA6106, AA6206, AA6306, AA6008, AA6009, AA6010, AA6110, AA6110A, AA6011, AA6111, AA6012, AA6012A, AA6013, AA6113, AA6014, AA6015, AA6016, AA6016A, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA6027, AA6028, AA6031, AA6032, AA6033, AA6040, AA6041, AA6042, AA6043, AA6151, AA6351, AA6351A, AA6451, AA6951, AA6053, AA6055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A, AA6261, AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, AA6963, AA6064, AA6064A, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091, or AA6092.

[0047] FIG. 1 provides an overview of an example method of making an aluminum alloy product. The method of FIG. 1 begins at 105, where an aluminum alloy 106 is cast to form a cast aluminum alloy product 107, such as an ingot or other cast product. At 110, the cast aluminum alloy product 107 is homogenized to form a homogenized aluminum alloy product 111. At 115, the homogenized aluminum alloy product 111 is subjected to one or more hot rolling passes and / or one or more cold rolling passes to form a rolled aluminum alloy product 112, which may correspond to an aluminum alloy product, such as an aluminum alloy plate, an aluminum alloy shate, or an aluminum alloy sheet. Optionally, the rolled aluminum alloy product 112 is subjected to additional processing steps, as described below, to form an aluminum alloy product.

[0048] Non-limiting examples of casting processes include a direct chill (DC) casting process or a continuous casting (CC) process. For example, FIG. 1 depicts a schematic illustration of a DC casting process at 105, but other casting processes can be used. A continuous casting system can include a pair of moving opposed casting surfaces (e.g., moving opposed belts, rolls or blocks), a casting cavity between the pair of moving opposed casting surfaces, and a molten metal injector. The molten metal injector can have an end opening from which molten metal can exit the molten metal injector and be injected into the casting cavity.

[0049] A cast aluminum alloy product, such as a cast ingot, cast slab, or other cast product, can be processed by any desirable techniques. Optionally, the processing steps can be used to prepare rolled aluminum alloy products, such as aluminum alloy sheets. Example optional processing steps include, but are not limited to, homogenization, hot rolling, cold rolling, annealing, solution heat treatment, and pre-aging.Hot Rolling

[0050] A hot rolling step can be optionally performed. In some embodiments, prior to the start of hot rolling, a homogenization step may be performed to produce a homogenized product that is then subjected to the hot rolling step. In other embodiments, the hot rolling step can be performed directly subsequent to the casting step. The hot rolling step can be performed at a temperature between 250 °C to 550 °C (e.g., from 250 °C to 500 °C, from 250 °C to 425 °C, from 250 °C to 500 °C, or from 300 °C to 500 °C) to form a hot rolled aluminum alloy product (e.g., a hot rolled plate, a hot rolled shate or a hot rolled sheet) having a gauge between 2.0 mm and 12.0 mm (e.g., from 2.0 mm to 4.0 mm, from 4.0 mm to 6.0 mm, from 6.0 mm to 8.0 mm, from 8.0 mm to 10.0 mm, or from 10.0 mm to 12.0 mm). In certain aspects, the hot rolling step can be performed at a temperature of 250 °C, 260 °C, 270 °C, 280 °C, 290 °C, 300 °C, 310 °C, 320 °C, 330 °C, 340 °C, 350 °C, 360 °C, 370 °C, 380 °C, 390 °C, 400 °C, 410 °C, 420 °C, 430 °C, 440 °C, 450 °C, 460 °C, 470 °C, 480 °C, 490 °C, 500 °C, 510 °C, 520 °C, 530 °C, 540 °C, 550 °C, or anywhere in between. In some embodiments, the hot rolled aluminum alloy product can have a gauge of 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, 5.0 mm, 5.1 mm, 5.2 mm, 5.3 mm, 5.4 mm, 5.5 mm, 5.6 mm, 5.7 mm, 5.8 mm, 5.9 mm, 6.0 mm, 6.1 mm, 6.2 mm, 6.3 mm, 6.4 mm, 6.5 mm, 6.6 mm, 6.7 mm, 6.8 mm, 6.9 mm, 7.0 mm, 7.1 mm, 7.2 mm, 7.3 mm, 7.4 mm, 7.5 mm, 7.6 mm, 7.7 mm, 7.8 mm, 7.9 mm, 8.0 mm, 8.1 mm, 8.2 mm, 8.3 mm, 8.4 mm,8.5 mm, 8.6 mm, 8.7 mm, 8.8 mm, 8.9 mm, 9.0 mm, 9.1 mm, 9.2 mm, 9.3 mm, 9.4 mm, 9.5 mm, 9.6 mm, 9.7 mm, 9.8 mm, 9.9 mm, 10.0 mm, 10.1 mm, 10.2 mm, 10.3 mm, 10.4 mm, 10.5 mm, 10.6 mm, 10.7 mm, 10.8 mm, 10.9 mm, 11.0 mm, 11.1 mm, 11.2 mm, 11.3 mm, 11.4 mm, 11.5 mm, 11.6 mm, 11.7 mm, 11.8 mm, 11.9 mm, 12.0 mm, or anywhere in between. During hot rolling, temperatures and other operating parameters can be controlled so that a hot rolling exit temperature of the hot rolled aluminum alloy product upon exit from a hot rolling mill ranges from 200 °C to 450 °C (e.g., from 200 °C to 425 °C, from 200 °C to 300 °C, from 300 °C to 400 °C, or from 400 °C to 450 °C. For example, the hot rolling exit temperature of the hot rolled aluminum alloy product can be 250 °C, 260 °C, 270 °C, 280 °C, 290 °C, 300 °C, 310 °C, 320 °C, 330 °C, 340 °C, 350 °C, 360 °C, 370 °C, 380 °C, 390 °C, 400 °C, 410 °C, 420 °C, 430 °C, 440 °C, 450 °C, or anywhere in between. In some embodiments, the hot rolled aluminum alloy product can be held at the hot rolling exit temperature for a period of time.Cold Rolling

[0051] Cast, homogenized, or hot rolled products can be optionally cold rolled using cold rolling mills into thinner products, such as a cold rolled sheet. The cold rolled aluminum alloy product can have a gauge between about 0.7 mm to 5.0 mm (e.g., from 0.7 mm to 2.0 mm, from 2.0 mm to 4.0 mm, or from 3.0 mm to 5.0 mm). For example, the gauge or thickness of the cold rolled aluminum alloy product can be 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4.0 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, 5.0 mm, or anywhere in between. The cold rolling step can be performed at a temperature between 20 °C to 40 °C (e.g., from 20 °C to 30 °C or from 30 °C to 30 °C) to form the cold rolled aluminum alloy product. For example, the cold rolling step can be performed at a temperature of 20 °C, 21 °C, 22 °C, 23 °C, 24 °C, 25 °C, 26 °C, 27 °C, 28 °C, 29 °C, 30 °C, 31 °C, 32 °C, 33 °C, 34 °C, 35 °C, 36 °C, 37 °C, 38 °C, 39 °C, 40 °C, or anywhere in between. In some embodiments, the cold rolling step may be performed at room temperature. Upon exit from a cold rolling mill, the cold rolled aluminum alloy product can have a cold rolling exit temperature ranging from 80 °C to 160 °C (e.g., from 80 °C to 100 °C, from 100 °C to 160 °C, or from 90 °C to 140 °C). For example, the cold rolling exit temperature can be 80 °C, 90 °C, 100 °C, 110 °C, 120 °C, 130 °C, 140 °C, 150 °C, 160 °C, or anywhere in between. Insome embodiments, the cold rolled aluminum alloy product and / or the hot rolled aluminum alloy product can be referred to as a rolled aluminum alloy product or a rolled product.Annealing

[0052] Subsequently, a rolled aluminum alloy product can undergo an annealing step. In general, annealing can be a heat treatment applied to reduce the hardness or stiffness of an aluminum alloy product. In certain cases, the annealing step can be performed subsequent to the hot rolling step or subsequent to the cold rolling step. The annealing step may be performed immediately after the hot rolling step. In some embodiments, producing the aluminum alloy product can involve multiple annealing steps. By way of example, a rolled aluminum alloy product produced from a hot rolling step can be subjected to a first annealing step. Subsequent to the first annealing step, the rolled aluminum alloy product can undergo a cold rolling step. Subsequent to the cold rolling step, the rolled aluminum alloy product can undergo a second annealing step.

[0053] In some embodiments, the annealing step can involve batch annealing the rolled aluminum alloy product by subjecting the rolled aluminum alloy product to an annealing temperature ranging from 300 °C to 500 °C (e.g., from 300 °C to 400 °C, from 400 °C to 500 °C, or from 350 °C to 450 °C). For example, the annealing temperature can be 300 °C, 310 °C, 320 °C, 330 °C, 340 °C, 350 °C, 360 °C, 370 °C, 380 °C, 390 °C, 400 °C, 410 °C, 420 °C, 430 °C, 440 °C, 450 °C, 460 °C, 470 °C, 480 °C, 490 °C, 500 °C, or anywhere in between. The annealing step can be performed for a period of time from 1 hour to 10 hours (e.g., from 1 hour to 3 hours, from 3 hours to 6 hours, or from 6 hours to 10 hours). For example, the annealing step can be performed for 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, or anywhere in between. In other embodiments, the annealing step can involve self-annealing the rolled aluminum alloy product using residual heat from the hot rolling step or the cold rolling step. In certain cases, the annealing step can be performed using residual heat corresponding to the hot rolling exit temperature or the cold rolling exit temperature. In other words, in some examples, further heat treatment is not applied after providing the rolled aluminum alloy product in O-temper. Accordingly, residual heat from the hot rolling exit temperature or the cold rolling exit temperature can be sufficient to perform the annealing step such that the annealing step may forgo an additional heating step.Coiling

[0054] In some embodiments, a rolled product can optionally undergo a coiling step. In certain cases, the rolled product may undergo the coiling step subsequent to the annealingstep. Optionally, the rolled product can be coiled into a coiled product upon exit from the hot rolling mill or the cold rolling mill. In some embodiments, the coiling step can be performed by coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature or the cold rolling exit temperature. In some embodiments, the coiling step can involve coiling the rolled aluminum alloy product at the hot rolling exit temperature or the cold rolling exit temperature. In certain cases, external heat (e.g., via a heating element, oven, etc.) is not supplied to process the rolled aluminum alloy product during coiling of the rolled product using residual heat corresponding to the hot rolling exit temperature. In some aspects, the coiled product is cooled, such as air cooled. In some embodiments, the cooled coiled product is stored, such as at room temperature (e.g., approximately 20 °C) for a period of time. The cooled coiled product can be stored for hours, days, weeks, months, or years.Properties of the Disclosed Aluminum Alloy Products

[0055] The aluminum alloy products can exhibit suitable mechanical properties for automotive applications after undergoing the processing steps described herein. In some embodiments, the aluminum alloy products exhibit a yield strength ranging from 25 MPa to 100 MPa (e.g., from 25 MPa to 40 MPa, from 40 MPa to 60 MPa, or from 60 MPa to 100 MPa). For example, the yield strength of the aluminum alloy products can be 25 MPa, 26 MPa, 27 MPa, 28 MPa, 29 MPa, 30 MPa, 31 MPa, 32 MPa, 33 MPa, 34 MPa, 35 MPa, 36 MPa, 37 MPa, 38 MPa, 39 MPa, 40 MPa, 41 MPa, 42 MPa, 43 MPa, 44 MPa, 45 MPa, 46 MPa, 47 MPa, 48 MPa, 49 MPa, 50 MPa, 51 MPa, 52 MPa, 53 MPa, 54 MPa, 55 MPa, 56 MPa, 57 MPa, 58 MPa, 59 MPa, 60 MPa, 61 MPa, 62 MPa, 63 MPa, 64 MPa, 65 MPa, 66 MPa, 67 MPa, 68 MPa, 69 MPa, 70 MPa, 71 MPa, 72 MPa, 73 MPa, 74 MPa, 75 MPa, 76 MPa, 77 MPa, 78 MPa, 79 MPa, 80 MPa, 81 MPa, 82 MPa, 83 MPa, 84 MPa, 85 MPa, 86 MPa, 87 MPa, 88 MPa, 89 MPa, 90 MPa, 91 MPa, 92 MPa, 93 MPa, 94 MPa, 95 MPa, 96 MPa, 97 MPa, 98 MPa, 99 MPa, 100 MPa, or anywhere in between. In some embodiments, the aluminum alloy products can exhibit an ultimate tensile strength (UTS) ranging from 125 MPa to 200 MPa (e.g., from 125 MPa to 130 MPa, from 130 MPa to 140 MPa, from 140 MPa to 150 MPa, from 150 MPa to 160 MPa, from 160 MPa to 170 MPa, from 170 MPa to 180 MPa, from 180 MPa to 190 MPa, or from 190 MPa to 200 MPa). For example, the UTS of the aluminum alloy products can be 125 MPa, 126 MPa, 127 MPa, 128 MPa, 129 MPa, 130 MPa, 131 MPa, 132 MPa, 133 MPa, 134 MPa, 135 MPa, 136 MPa, 137 MPa, 138 MPa, 139 MPa, 140 MPa, 141 MPa, 142 MPa, 143 MPa, 144 MPa, 145 MPa, 146 MPa, 147 MPa,148 MPa, 149 MPa, 150 MPa, 151 MPa, 152 MPa, 153 MPa, 154 MPa, 155 MPa, 156 MPa, 157 MPa, 158 MPa, 159 MPa, 160 MPa, 161 MPa, 162 MPa, 163 MPa, 164 MPa, 165 MPa, 166 MPa, 167 MPa, 168 MPa, 169 MPa, 170 MPa, 171 MPa, 172 MPa, 173 MPa, 174 MPa, 175 MPa, 176 MPa, 177 MPa, 178 MPa, 179 MPa, 180 MPa, 181 MPa, 182 MPa, 183 MPa, 184 MPa, 185 MPa, 186 MPa, 187 MPa, 188 MPa, 189 MPa, 190 MPa, 191 MPa, 192 MPa, 193 MPa, 194 MPa, 195 MPa, 196 MPa, 197 MPa, 198 MPa, 199 MPa, 200 MPa, or anywhere in between.

[0056] In some embodiments, the aluminum alloy products can exhibit an elongation ranging from 18 % to 26 % (e.g., from 18 % to 20 %, from 20 % to 22 %, from 22 % to 24 %, or from 24 % to 26 %). For example, the aluminum alloy products can exhibit elongation properties of 18 %, 19 %, 20 %, 21 %, 22 %, 23 %, 24 %, 25 %, 26 %, or anywhere in between. In some embodiments, the aluminum alloy products can exhibit a post-uniform elongation ranging from 4 % to 8 % (e.g., from 4 % to 7 %, from 5 % to 7 %, from 6 % to 7 %, or from 7 % to 8 %). For example, the aluminum alloy product can exhibit post-uniform elongation of 4 %, 5 %, 6 %, 7 %, 8 %, or anywhere in between.

[0057] In some embodiments, the aluminum alloy products can exhibit a strain hardening value (e.g., an n-value) that has a local maximum at a plastic strain of 0.015 to 0.05 (e.g., from 0.015 to 0.030 or from 0.030 to 0.050). For example, when plotting the strain hardening value versus plastic strain, the aluminum alloy products can exhibit a peak at a plastic strain of 0.015, 0.020, 0.025, 0.030, 0.035, 0.040, 0.045, 0.050, or anywhere in between.Methods of Using the Disclosed Aluminum Alloy Products

[0058] The aluminum alloy products described herein can be used in automotive applications and other transportation applications, including aircraft and railway applications. For example, the disclosed aluminum alloy products can be used to prepare automotive structural parts, such automotive inner applications. Non-limiting examples of automotive structural parts include bumpers, inner panels, outer panels, side panels, inner hoods, outer hoods, deep drawn parts, or trunk lid panels.

[0059] The examples disclosed herein will serve to further illustrate aspects of the invention without, at the same time, 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. The examples and embodiments described herein may also make use ofconventional procedures, unless otherwise stated. Some of the procedures are described herein for illustrative purposes.EXAMPLE 1

[0060] Sample aluminum alloys prepared using the methods described herein were tested to investigate mechanical properties of aluminum alloy products described herein. The methods described herein can produce 5xxx series aluminum alloys or 6xxx series aluminum alloys that exhibit suitable stiffness and formability despite forgoing solution heat treatment and artificial aging. Through adjusting processing conditions, the stiffness, formability, and / or other mechanical properties of the aluminum alloys can be controlled to be sufficiently similar to the mechanical properties of conventional aluminum alloys typically produced for automotive applications, such as high-strength 6xxx series aluminum alloys.

[0061] Experimental trials were conducted to investigate the processing steps described herein and their effect on mechanical properties of the sample 5xxx / 6xxx series aluminum alloys or 6xxx series aluminum alloys in O-temper. Sample Alloys 1-8 described herein are modified 5xxx / 6xxx series aluminum alloys or 6xxx series aluminum alloys that achieve suitable stiffness and high formability properties despite being produced using methods that forgo solution heat treatment and artificial aging. The methods described herein provide a cost-effective and pedestrian-friendly alternative to conventional aluminum alloys used in automotive applications. Comparative Alloys 1-3 described herein are 5xxx series aluminum alloys typically used in automotive applications. The compositions of the Sample Alloys 1-8 and Comparative Alloys 1-3 are provided below in Table 2.

[0062] FIG. 2 shows a plot of measured yield strength (MPa) and ultimate tensile strength (MPa) versus calculated solid solution after batch annealing is applied to Sample Alloys 1-8 and Comparative Alloys 1-3. A first target range 205 shown in FIG. 2 corresponds to a specification space (e.g., from 70 MPa to 120 MPa) for yield strength. A second target range 210 corresponds to a specification space (e.g., a minimum of 175 MPa) for ultimate tensile strength. Additional treatment techniques, such as plant processing or tension leveling post annealing, can increase strength properties by 10-15 MPa, which can cause one or more of the Sample Alloys 1-8 to be within the first target range 205. Table 3 below provides the measured yield strength and tensile strength of the Sample Alloys 1-8 and the Comparative Alloys 1-3. Sample Alloy 3 was tested using two process routes: hot roll to gauge (HRTG) and cold temperature (CT). HRTG can involve hot rolling to a final gauge without cold rolling, solutionizing, quenching, natural aging, and / or artificial aging.

[0063] FIG. 3 shows a plot of uniform elongation (%) and post-uniform elongation (%) for example 5xxx series or 6xxx series aluminum alloys. Lower values 305 correspond to uniform elongation. Upper values 310 indicate post-uniform elongation. As shown, the Sample Alloys 1-8 exhibit higher uniform elongation and post-uniform elongation compared to Comparative Alloys 1-3. In general, post-uniform elongation can be determined by subtracting the uniform elongation from a total elongation. Additionally, post-uniform elongation relates to formability by representing a material’s ability to resist fracture typically caused by strain localization. A higher post-uniform elongation can be beneficial with respect to applications that involve forming parts that are not strength driven. In general, O-temper results in higher post-uniform elongation properties compared to other tempers, such as T4 temper. As described herein, O-temper can be achieved using annealing such that solution heat treatment can be forgone. In some embodiments, O-temper can be achieved directly from a rolling mill (e.g., a hot mill or a cold mill) if a coiling temperature from an exit temperature of the rolling mill is sufficient to drive self-annealing, thereby forgoing any further thermal processing and reducing costs and carbon footprint of production.

[0064] FIG. 4 shows a plot of instantaneous n-values versus plastic strain (-) for an example alloy in O-temper and comparative alloys in O-temper and T4 temper. The n-values can be strain hardening exponents that can quantify an ability of a material to become stronger due to strain hardening or deformation. Dataset 405 corresponds to Sample Alloy 8 in O-temper. Dataset 410, dataset 415, and dataset 420 respectively correspond to Comparative Alloy 1 in O-temper, Comparative Alloy 2 in O-temper produced using solution heat treatment, and Comparative Alloy 3 in O-temper. Dataset 425 corresponds to a differentcomparative alloy produced using AA6014 in T4 temper with solution heat treatment. As shown in FIG. 4, dataset 405 exhibits a rapid decay of its n-value after a steep increase. The n-value of dataset 405 begins to decay at a plastic strain of about 0.03. In contrast, the remaining datasets in FIG. 4 (e.g., dataset 410, dataset 415, dataset 420, and dataset 425) each show a brief increase that decreases at a relatively slow rate compared to dataset 405. As described herein, the n-values can indicate a rate of hardening of a material. Dataset 405 exhibiting an initially high n-value that rapidly decays indicates that Sample Alloy 8 is not rapidly hardening, which can result in reduced stiffness that can be beneficial with respect to pedestrian safety applications.

[0065] FIG. 5 shows a plot comparing instantaneous n-values versus plastic strain (-) for variations of an example alloy in an O-temper that have undergone or have forgone prestraining and paint baking. Dataset 505 corresponds to Sample Alloy 8 in O-temper that has forgone any additional processing steps, such as pre-straining and paint baking. Dataset 510 corresponds to Sample Alloy 8 in O-temper that has undergone 2% pre-straining and paint baking. Dataset 515 corresponds to Sample Alloy 8 in O-temper that has undergone 5% prestraining and paint baking. As shown in FIG. 5, n-value properties described above with respect to FIG. 4 are consistent when other processing steps are applied to Sample Alloy 8 in O-temper. For example, each dataset shown in FIG. 5 has an initially high n-value with a maximum at a plastic strain of about 0.03 that rapidly decreases thereafter.ILLUSTRATIVE ASPECTS

[0066] As used below, any reference to a series of aspects (e.g., “Aspects 1-4”) or nonenumerated group of aspects (e.g., “any previous or subsequent aspect”) is to be understood as a reference to each of those aspects disjunctively (e.g., “Aspects 1-4” is to be understood as “Aspects 1, 2, 3, or 4”).

[0067] Aspect l is a method of producing an aluminum alloy product, the method comprising: casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof; hot rolling the aluminum alloy to produce a rolled aluminum alloy product; and processing the rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper: holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time; annealing the rolled aluminum alloy product; coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; or coiling the rolled aluminum alloy product at the hot rolling exit temperature.1

[0068] Aspect 2 is the method of any previous or subsequent aspect, further comprising cold rolling the rolled aluminum alloy product.

[0069] Aspect 3 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product is a cold rolled aluminum alloy product having a thickness from 0.70 mm to 5.00 mm.

[0070] Aspect 4 is the method of any previous or subsequent aspect, wherein the hot rolling exit temperature ranges from 200 °C to 450 °C.

[0071] Aspect 5 is the method of any previous or subsequent aspect, wherein the annealing step is performed immediately after the hot rolling step.

[0072] Aspect 6 is the method of any previous or subsequent aspect, wherein the annealing step comprises self-annealing the rolled aluminum alloy product using the residual heat from the hot rolling step.

[0073] Aspect 7 is the method of any previous or subsequent aspect, wherein the annealing step is batch annealing the rolled aluminum alloy product at an annealing temperature ranging from 300 °C to 500 °C for 1 hour to 10 hours.

[0074] Aspect 8 is the method of any previous or subsequent aspect, wherein external heat is not supplied to process the rolled aluminum alloy product during coiling of the rolled aluminum alloy product using the residual heat corresponding to the hot rolling exit temperature.

[0075] Aspect 9 is the method of any previous or subsequent aspect, wherein the aluminum alloy product exhibits a yield strength ranging from 25 MPa to 100 MPa.

[0076] Aspect 10 is the method of any previous or subsequent aspect, wherein the aluminum alloy product exhibits an ultimate tensile strength (UTS) ranging from 125 MPa to 200 MPa.

[0077] Aspect 11 is the method of any previous or subsequent aspect, wherein the aluminum alloy product exhibits an elongation ranging from 18 % to 26 %.

[0078] Aspect 12 is the method of any previous or subsequent aspect, wherein the aluminum alloy product exhibits a post-uniform elongation ranging from 4 % to 8 %.

[0079] Aspect 13 is the method of any one of any previous or subsequent aspect, wherein the method does not include an artificial aging step.

[0080] Aspect 14 is the method of any one of any previous or subsequent aspect, wherein the method does not include a solution heat treatment step.

[0081] Aspect 15 is the method of any one of any previous or subsequent aspect, wherein further heat treatment is not applied after providing the rolled aluminum alloy product in the O-temper.

[0082] Aspect 16 is the method of any one of any previous or subsequent aspect, wherein the aluminum alloy comprises 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities.

[0083] Aspect 17 is the method of any one of any previous or subsequent aspect, wherein a strain hardening value of the aluminum alloy product has a local maximum at a plastic strain of 0.015 to 0.05.

[0084] Aspect 18 is a method of producing an aluminum alloy product, the method comprising: casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof, wherein the aluminum alloy comprises 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities; hot rolling the aluminum alloy to produce a rolled aluminum alloy product; and processing the rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper: holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time; annealing the rolled aluminum alloy product; coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; or coiling the rolled aluminum alloy product at the hot rolling exit temperature.

[0085] Aspect 19 is a method of producing an aluminum alloy product, the method comprising: casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof; hot rolling the aluminum alloy to produce a hot rolled aluminum alloy product; optionally cold rolling the hot rolled aluminum alloy product to produce a cold rolled aluminum alloy product; and processing a rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper, wherein the rolled aluminum alloy product is the hot rolled aluminum alloy product or the cold rolled aluminum alloy product, wherein no solution heat treatment is performed to process the rolled aluminum alloy product: holding the rolled aluminum alloy product at an exit temperature for a period of time, wherein the exit temperature is a hot rolling exit temperature of the hot rolling step or a cold rolling exit temperature of the cold rolling step; annealing the rolled aluminum alloy product; coiling therolled aluminum alloy product using residual heat corresponding to the exit temperature; or coiling the rolled aluminum alloy product at the exit temperature.

[0086] Aspect 20 is the method of any previous or subsequent aspect, wherein the cold rolling exit temperature ranges from 80 °C to 160 °C.

[0087] Aspect 21 is an aluminum alloy product produced using the method of any previous or subsequent aspect.

[0088] Aspect 22 is the aluminum alloy product of any previous or subsequent aspect, wherein the aluminum alloy product is used for automotive inner applications.

[0089] Aspect 23 is the aluminum alloy product of any previous or subsequent aspect, wherein the aluminum alloy product is a deep drawn part.

[0090] All patents and publications cited herein are incorporated by reference in their entirety. The foregoing description of the embodiments, including illustrated embodiments, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or limiting to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art.

Claims

WHAT IS CLAIMED IS:

1. A method of producing an aluminum alloy product, the method comprising:casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof;hot rolling the aluminum alloy to produce a rolled aluminum alloy product; andprocessing the rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper:holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time;annealing the rolled aluminum alloy product;coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; orcoiling the rolled aluminum alloy product at the hot rolling exit temperature.

2. The method of claim 1, further comprising cold rolling the rolled aluminum alloy product.

3. The method of claim 2, wherein the rolled aluminum alloy product is a cold rolled aluminum alloy product having a thickness from 0.70 mm to 5.00 mm.

4. The method of claim 1, wherein the hot rolling exit temperature ranges from 200 °C to 450 °C.

5. The method of claim 1, wherein the annealing step is performed immediately after the hot rolling step.

6. The method of claim 1, wherein the annealing step comprises selfannealing the rolled aluminum alloy product using the residual heat from the hot rolling step.

7. The method of claim 1, wherein the annealing step is batch annealing the rolled aluminum alloy product at an annealing temperature ranging from 300 °C to 500 °C for 1 hour to 10 hours.

8. The method of claim 1, wherein external heat is not supplied to process the rolled aluminum alloy product during coiling of the rolled aluminum alloy product using the residual heat corresponding to the hot rolling exit temperature.

9. The method of claim 1, wherein the aluminum alloy product exhibits a yield strength ranging from 25 MPa to 100 MPa.

10. The method of claim 1, wherein the aluminum alloy product exhibits an ultimate tensile strength (UTS) ranging from 125 MPa to 200 MPa.

11. The method of claim 1, wherein the aluminum alloy product exhibits an elongation ranging from 18 % to 26 %.

12. The method of claim 1, wherein the aluminum alloy product exhibits a post-uniform elongation ranging from 4 % to 8 %.

13. The method of any one of claims 1-12, wherein the method does not include an artificial aging step.

14. The method of any one of claims 1-12, wherein the method does not include a solution heat treatment step.

15. The method of any one of claims 1-12, wherein further heat treatment is not applied after providing the rolled aluminum alloy product in the O-temper.

16. The method of any one of claims 1-12, wherein the aluminum alloy comprises 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities.

17. The method of any one of claims 1-12, wherein a strain hardening value of the aluminum alloy product has a local maximum at a plastic strain of 0.015 to 0.05.

18. A method of producing an aluminum alloy product, the method comprising:casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof, wherein the aluminum alloy comprises 0.37 wt. % to 1.25 wt. % Si, 0.20 wt. % to 0.46 wt. % Fe, 0.10 wt. % to 0.83 wt. % Cu, 0.03 wt. % to 0.40 wt. % Mn, 0.31 wt. % to 1.85 wt. % Mg, 0.01 wt. % to 0.18 wt. % Cr, and a remainder Al and unavoidable impurities;hot rolling the aluminum alloy to produce a rolled aluminum alloy product; andprocessing the rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper:holding the rolled aluminum alloy product at a hot rolling exit temperature for a period of time;annealing the rolled aluminum alloy product;coiling the rolled aluminum alloy product using residual heat corresponding to the hot rolling exit temperature; orcoiling the rolled aluminum alloy product at the hot rolling exit temperature.

19. A method of producing an aluminum alloy product, the method comprising:casting an aluminum alloy comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a combination thereof;hot rolling the aluminum alloy to produce a hot rolled aluminum alloy product;optionally cold rolling the hot rolled aluminum alloy product to produce a cold rolled aluminum alloy product; andprocessing a rolled aluminum alloy product according to one or more of the following steps to provide the rolled aluminum alloy product in an O-temper, wherein the rolled aluminum alloy product is the hot rolled aluminum alloy product or the cold rolled aluminum alloy product, wherein no solution heat treatment is performed to process the rolled aluminum alloy product:holding the rolled aluminum alloy product at an exit temperature for a period of time, wherein the exit temperature is a hot rolling exit temperature of the hot rolling step or a cold rolling exit temperature of the cold rolling step;annealing the rolled aluminum alloy product;coiling the rolled aluminum alloy product using residual heat corresponding to the exit temperature; orcoiling the rolled aluminum alloy product at the exit temperature.

20. The method of claim 19, wherein the cold rolling exit temperature ranges from 80 °C to 160 °C.

21. An aluminum alloy product produced using the method of any of claims 1-20.

22. The aluminum alloy product of claim 21, wherein the aluminum alloy product is used for automotive inner applications.

23. The aluminum alloy product of claim 21, wherein the aluminum alloy product is a deep drawn part.

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