JP7191077B2 - High-strength corrosion-resistant aluminum alloy and its manufacturing method - Google Patents

Description

The present disclosure relates to aluminum alloys and methods of making and processing the same. The present disclosure further relates to aluminum alloys that exhibit high mechanical strength, formability, and corrosion resistance.

High-strength, recyclable aluminum alloys enhance product performance in many applications, including transportation (including, but not limited to, trucks, trailers, trains, and ships), electronics, and automotive applications. desirable for improvement. For example, high-strength aluminum alloys in trucks or trailers are lighter than traditional steel alloys and provide the significant emission reductions needed to meet new, more stringent government emissions regulations. Such alloys should exhibit high strength, high formability and corrosion resistance. Additionally, such alloys are desirably formed from recycled content.

However, it has been a challenge to identify processing conditions and alloy compositions that provide such alloys, particularly alloys with recycled content. Alloying from recycled content may result in high zinc (Zn) and copper (Cu) content. High zinc alloys have traditionally lacked strength, and copper-containing alloys are prone to corrosion.

Exhaustive embodiments of the invention are defined by the claims, rather than by this summary of the invention. This Summary of the Invention 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 of the Invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used alone to determine the scope of the claimed subject matter. not. The subject matter should be understood by reference to the entire specification, any or all drawings, and appropriate portions of each claim.

Herein, about 0.25-1.3 wt% Si, 1.0-2.5 wt% Mg, 0.5-1.5 wt% Cu, up to 0.2 wt% Fe , up to 3.0 wt.% Zn, up to 0.15 wt.% impurities, with the balance Al. Optionally, the aluminum alloy comprises about 0.55-1.1 wt% Si, 1.25-2.25 wt% Mg, 0.6-1.0 wt% Cu, 0.05-0 .17 wt.% Fe, 1.5-3.0 wt.% Zn, up to 0.15 wt.% impurities, with the balance Al. Optionally, the aluminum alloy comprises about 0.65-1.0 wt% Si, 1.5-2.25 wt% Mg, 0.6-1.0 wt% Cu, 0.12-0 .17 wt.% Fe, 2.0-3.0 wt.% Zn, up to 0.15 wt.% impurities, with the balance Al. Optionally, the aluminum alloys described herein can further include Zr and/or Mn. Zr can be present in an amount up to about 0.15 wt% (eg, about 0.09-0.12 wt%). Mn can be present in an amount up to about 0.5 wt% (eg, about 0.05-0.3 wt%).

Optionally, the ratio of Mg to Si (ie, the Mg/Si ratio) is from about 1.5:1 to about 3.5:1. For example, the Mg/Si ratio can be from about 2.0:1 to about 3.0:1. Optionally, the Zn to Mg/Si ratio (ie, the Zn/(Mg/Si) ratio) is from about 0.75:1 to about 1.4:1. For example, the Zn/(Mg/Si) ratio can be from about 0.8:1 to about 1.1:1. Optionally, the ratio of Cu to Zn/(Mg/Si) ratio (i.e. Cu/[Zn/(Mg/Si)] ratio) is from about 0.7 to 1 to about 1.4 to 1 . For example, the Cu/[Zn/(Mg/Si)] ratio is from about 0.8:1 to about 1.1:1.

Also described herein are aluminum alloy products comprising the aluminum alloys described herein. The aluminum alloy product can have a yield strength of at least about 340 MPa (eg, about 360 MPa to about 380 MPa) at a T6 temper. The aluminum alloy products described herein can be corrosion resistant and have an average intergranular corrosion pitting depth of less than about 100 μm at the T6 temper. The aluminum alloy product also exhibits excellent bendability and can have an r/t (bendability) ratio of about 0.5 or less at the T4 temper.

Optionally, the aluminum alloy product comprises one or _more precipitates selected from the group consisting of _MgZn2 /Mg _{( Zn} ,Cu) ₂ , _Mg2Si , and _Al4Mg8Si7Cu2 . The aluminum alloy product _comprises MgZn2/Mg(Zn,Cu) ₂ in an average amount of at least about 300,000,000 particles/ ^mm2 , Mg2Si in an average amount of at ^least about 600,000,000 particles/ _mm2 , and/or Al ₄ Mg ₈ Si ₇ Cu ₂ in an average amount of at least about 600,000,000 particles/mm ² . _In some examples, the aluminum alloy product includes _MgZn2 /Mg _{( Zn} ,Cu) ₂ , _Mg2Si , and _Al4Mg8Si7Cu2 . The ratio of Mg ₂ Si to Al ₄ Mg ₈ Si ₇ Cu ₂ can be from about 1:1 to about 1.5:1 and the ratio of Mg ₂ Si to MgZn ₂ /Mg(Zn,Cu) ₂ can be about 1.5:1 to about 3:1 and the ratio of Al ₄ Mg ₈ Si ₇ Cu _{2 to} MgZn ₂ /Mg(Zn,Cu) ₂ is about 1.5:1 to about 3:1. can be.

Further described herein are methods of making aluminum alloys. The method includes casting an aluminum alloy as described herein to form an aluminum alloy cast product, homogenizing the aluminum alloy cast product, and hot rolling the homogenized aluminum alloy cast product. providing a final gauge aluminum alloy; and solution heat treating the final gauge aluminum alloy. The method may further include preaging the final gauge aluminum alloy. Optionally, the aluminum alloy is cast from a molten aluminum alloy comprising scrap metal, eg, scrap metal containing 6xxx series aluminum alloys, 7xxx series aluminum alloys, or combinations thereof.

4 is a graph showing the increase in magnesium zinc precipitates with increasing magnesium content in aluminum alloys prepared according to certain aspects of the present disclosure; 1 is a differential scanning calorimetry graph of an aluminum alloy according to certain aspects of the present disclosure; 1 is a differential scanning calorimetry graph of an aluminum alloy according to certain aspects of the present disclosure; 1 is a transmission electron microscope photomicrograph showing precipitate types in an aluminum alloy according to certain embodiments of the present disclosure; 1 is a transmission electron microscope photomicrograph showing precipitate types in an aluminum alloy according to certain embodiments of the present disclosure; 2 is a graph showing precipitate compositions of aluminum alloys according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing precipitate formation after various processing steps in an aluminum alloy according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing precipitate formation after various processing steps in an aluminum alloy according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing precipitate formation after various processing steps in an aluminum alloy according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing the grain population and grain structure of an aluminum alloy according to certain embodiments of the present disclosure; 1 is a series of optical micrographs showing the grain population and grain structure of an aluminum alloy according to certain embodiments of the present disclosure; 4 is a graph showing electrical conductivity of aluminum alloys according to certain aspects of the present disclosure; 4 is a graph showing electrical conductivity of aluminum alloys according to certain aspects of the present disclosure; 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles) and total elongation (open diamonds) of aluminum alloys according to certain aspects of the present disclosure. 4 is a graph showing load-displacement data from a 90° bend test of an aluminum alloy according to certain aspects of the present disclosure; 4 is a graph showing load-displacement data from a 90° bend test of an aluminum alloy according to certain aspects of the present disclosure; 4 is a graph showing load-displacement data from a 90° bend test of an aluminum alloy according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing corrosion attack in an aluminum alloy according to certain aspects of the present disclosure; 1 is a series of optical micrographs showing corrosion attack of an aluminum alloy according to certain aspects of the present disclosure; 1 is an optical micrograph of an aluminum alloy according to certain aspects of the present disclosure; 1 is an optical micrograph of an aluminum alloy according to certain aspects of the present disclosure; 1 is an optical micrograph of an aluminum alloy according to certain aspects of the present disclosure;

High strength aluminum alloys and methods of making and processing such alloys are described. The aluminum alloys described herein exhibit improved mechanical strength, deformability, and corrosion resistance properties. Additionally, aluminum alloys can be prepared from recycled materials. Aluminum alloy products prepared from the alloys described herein contain strength _- enhancing precipitates such as _MgZn2 / _{Mg (} Zn,Cu) ₂ , _Mg2Si , and _Al4Mg8Si7Cu2 .

Definition and explanation:
As used herein, the terms "invention,""theinvention,""thisinvention," and "the present invention" refer broadly to all of the subject matter of this patent application and the following "claims." is intended. Statements containing these terms should not be understood as limiting the subject matter described herein or as limiting the meaning or scope of the following claims.

In this description, reference is made to alloys identified by aluminum industry designations, such as "series," or "6xxx."アルミニウムおよびその合金の命名および識別に最も一般的に使用されている番号記号システムを理解するために、「Ｉｎｔｅｒｎａｔｉｏｎａｌ Ａｌｌｏｙ Ｄｅｓｉｇｎａｔｉｏｎｓ ａｎｄ Ｃｈｅｍｉｃａｌ Ｃｏｍｐｏｓｉｔｉｏｎ Ｌｉｍｉｔｓ ｆｏｒ Ｗｒｏｕｇｈｔ Ａｌｕｍｉｎｕｍ ａｎｄ Ｗｒｏｕｇｈｔ Ａｌｕｍｉｎｕｍ Ａｌｌｏｙｓ」または「Ｒｅｇｉｓｔｒａｔｉｏｎ Ｒｅｃｏｒｄ ｏｆ Ａｌｕｍｉｎｕｍ Ａｓｓｏｃｉａｔｉｏｎ Ａｌｌｏｙ Designs and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot, both published by the Aluminum Industry Association.

As used herein, the meaning of "a," "an," or "the" refers to singular and plural references, unless the context clearly dictates otherwise. including.

As used herein, plates generally have a thickness greater than about 6 mm. For example, a plate is greater than 6 mm, greater than 10 mm, greater than 15 mm, greater than 20 mm, greater than 25 mm, greater than 30 mm, greater than 35 mm, greater than 40 mm, greater than 45 mm, greater than 50 mm, or greater than 100 mm. It can refer to an aluminum product with thickness.

As used herein, the term "slab" indicates an alloy thickness ranging from about 5 mm to about 50 mm. For example, a slab can have a thickness of 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, or 50 mm.

As used herein, a sheet (also referred to as a sheet plate) generally has a thickness of about 4 mm to about 15 mm. For example, the sheet can have a thickness of 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, or 15 mm.

As used herein, sheet generally refers to aluminum products having a thickness of less than about 4 mm. For example, the sheet can have a thickness of less than 4 mm, less than 3 mm, less than 2 mm, less than 1 mm, less than 0.5 mm, less than 0.3 mm, or 0.1 mm.

In this application, reference is made to the degree or condition of the alloy. See "American National Standards (ANSI) H35 on Alloy and Temper Designation Systems" for an understanding of descriptions of the most commonly used alloy tempering degrees. F-state or tempered refers to the as-manufactured aluminum alloy. The O state or temper refers to the aluminum alloy after annealing. The T4 condition or temper refers to aluminum alloys after solution heat treatment (SHT) (ie, solution annealing) followed by natural aging. The T6 condition or temper refers to aluminum alloys after solution heat treatment and subsequent artificial aging (AA). The T8x condition or temper refers to aluminum alloys after solution heat treatment followed by cold working and subsequent artificial aging.

As used herein, the terms "cast metal article", "cast product" and the like are used interchangeably to refer to direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (e.g. (including by use of a twin belt caster, twin roll caster, block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method; point to the product.

As used herein, “room temperature” means about 15° C. to about 30° C., such as about 15° C., about 16° C., about 17° C., about 18° C., about 19° C., about 20° C., C., about 21.degree. C., about 22.degree. C., about 23.degree. C., about 24.degree. C., about 25.degree.

All ranges disclosed herein are understood to encompass any and all subranges subsumed therein. For example, a range recited as "1 to 10" includes any and all subranges between (and including) the minimum value of 1 and the maximum value of 10, i.e., a minimum value of 1 or greater, e.g. , 1-6.1 and ending with a maximum value of 10 or less, eg, 5.5-10.

The following aluminum alloys are listed with respect to their elemental composition in weight percentages (wt%) based on the total weight of the alloy. In the particular example of each alloy, the remainder is aluminum, with a maximum weight percent of 0.15% for the total impurities.

ALLOY COMPOSITIONS New aluminum alloys are described below. In certain aspects, the alloy exhibits high strength, high formability, and corrosion resistance. The properties of an alloy are obtained by the elemental composition of the alloy and the method of processing the alloy to produce aluminum alloy products including sheet, plate and plate.

In certain embodiments, the alloy has a Cu content of from about 0.5 wt.% to about 1.5 wt.%, 0.5 wt. 07 wt % to about 0.12 wt %, and a controlled Si to Mg ratio.

The alloy may have the following elemental composition, as provided in Table 1.

In some examples, the alloy may have the following elemental composition as provided in Table 2.

In some examples, the alloy may have the following elemental composition as provided in Table 3.

In some examples, the disclosed alloys contain about 0.25% to about 1.3% (eg, about 0.55% to about 1.1%, or about 0.55% to about 1.1%), based on the total weight of the alloy. 65% to about 1.0%) of silicon (Si). For example, the alloy may contain about 0.25%, about 0.26%, about 0.27%, about 0.28%, about 0.29%, about 0.3%, about 0.31%, about 0.3%. 32%, about 0.33%, about 0.34%, about 0.35%, about 0.36%, about 0.37%, about 0.38%, about 0.39%, about 0.4% , 0.41%, about 0.42%, about 0.43%, about 0.44%, about 0.45%, about 0.46%, about 0.47%, about 0.48%, about 0 .49%, about 0.5%, about 0.51%, about 0.52%, about 0.53%, about 0.54%, about 0.55%, about 0.56%, about 0.57 %, about 0.58%, about 0.59%, about 0.6%, about 0.61%, about 0.62%, about 0.63%, about 0.64%, about 0.65%, about 0.66%, about 0.67%, about 0.68%, about 0.69%, about 0.7%, about 0.71%, about 0.72%, about 0.73%, about 0 .74%, about 0.75%, about 0.76%, about 0.77%, about 0.78%, about 0.79%, about 0.8%, about 0.81%, about 0.82 %, about 0.83%, about 0.84%, about 0.85%, about 0.86%, about 0.87%, about 0.88%, about 0.89%, about 0.9%, about 0.91%, about 0.92%, about 0.93%, about 0.94%, about 0.95%, about 0.96%, about 0.97%, about 0.98%, about 0 .99%, about 1.0%, about 1.01%, about 1.02%, about 1.03%, about 1.04%, about 1.05%, about 1.06%, about 1.07 %, about 1.08%, about 1.09%, about 1.1%, about 1.11%, about 1.12%, about 1.13%, about 1.14%, about 1.15%, about 1.16%, about 1.17%, about 1.18%, about 1.19%, about 1.2%, about 1.21%, about 1.22%, about 1.23%, about 1 .24%, about 1.25%, about 1.26%, about 1.27%, about 1.28%, about 1.29%, or about 1.3% Si. All percentages are expressed in weight percent.

In some examples, the alloys described herein contain up to about 0.2% (eg, from about 0.05% to about 0.17% or from about 0.12% to about 0.17%) of iron (Fe). For example, the alloy may contain about 0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%, about 0.07%, about 0.07%. 08%, about 0.09%, about 0.1%, about 0.11%, about 0.12%, about 0.13%, about 0.14%, about 0.15%, about 0.16% , about 0.17%, about 0.18%, about 0.19%, or about 0.2% Fe. In some cases Fe is not present in the alloy (ie 0%). All percentages are expressed in weight percent.

In some examples, the alloys described herein contain up to about 0.5% (eg, from about 0.05% to about 0.3% or from about 0.05% to about 0.2%) of manganese (Mn). For example, the alloy may contain about 0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%, about 0.07%, about 0.07%. 08%, about 0.09%, about 0.1%, about 0.11%, about 0.12%, about 0.13%, about 0.14%, about 0.15%, about 0.16% , about 0.17%, about 0.18%, about 0.19%, about 0.2%, about 0.21%, about 0.22%, about 0.23%, about 0.24%, about 0.25%, about 0.26%, about 0.27%, about 0.28%, about 0.29%, about 0.3%, about 0.31%, about 0.32%, about 0.3%. 33%, about 0.34%, about 0.35%, about 0.36%, about 0.37%, about 0.38%, about 0.39%, about 0.4%, about 0.41% , about 0.42%, about 0.43%, about 0.44%, about 0.45%, about 0.46%, about 0.47%, about 0.48%, about 0.49%, or It may contain about 0.5% Mn. In some cases, Mn is absent (ie, 0%) in the alloy. All percentages are expressed in weight percent.

In some examples, the disclosed alloys contain about 1.0% to about 2.5% (eg, about 1.25% to about 2.25%, or about 1.5%, based on the total weight of the alloy). 5% to about 2.25%) of magnesium (Mg). For example, the alloy may contain about 1.0%, about 1.01%, about 1.02%, about 1.03%, about 1.04%, about 1.05%, about 1.06%, about 1.0%. 07%, about 1.08%, about 1.09%, about 1.1%, about 1.11%, about 1.12%, about 1.13%, about 1.14%, about 1.15% , about 1.16%, about 1.17%, about 1.18%, about 1.19%, about 1.2%, about 1.21%, about 1.22%, about 1.23%, about 1.24%, about 1.25%, about 1.26%, about 1.27%, about 1.28%, about 1.29%, about 1.3%, about 1.31%, about 1.3%. 32%, about 1.33%, about 1.34%, about 1.35%, about 1.36%, about 1.37%, about 1.38%, about 1.39%, about 1.4% , about 1.41%, about 1.42%, about 1.43%, about 1.44%, about 1.45%, about 1.46%, about 1.47%, about 1.48%, about 1.49%, about 1.5%, about 1.51%, about 1.52%, about 1.53%, about 1.54%, about 1.55%, about 1.56%, about 1.5%. 57%, about 1.58%, about 1.59%, about 1.6%, about 1.61%, about 1.62%, about 1.63%, about 1.64%, about 1.65% , about 1.66%, about 1.67%, about 1.68%, about 1.69%, about 1.7%, about 1.71%, about 1.72%, about 1.73%, about 1.74%, about 1.75%, about 1.76%, about 1.77%, about 1.78%, about 1.79%, about 1.8%, about 1.81%, about 1.7%. 82%, about 1.83%, about 1.84%, about 1.85%, about 1.86%, about 1.87%, about 1.88%, about 1.89%, about 1.9% , about 1.91%, about 1.92%, about 1.93%, about 1.94%, about 1.95%, about 1.96%, about 1.97%, about 1.98%, about 1.99%, about 2.0%, about 2.01%, about 2.02%, about 2.03%, about 2.04%, about 2.05%, about 2.06%, about 2.0%. 07%, about 2.08%, about 2.09%, about 2.1%, about 2.11%, about 2.12%, about 2.13%, about 2.14%, about 2.15% , about 2.16%, about 2.17%, about 2.18%, about 2.19%, about 2.2%, about 2.21%, about 2.22%, about 2.23%, about 2.24%, about 2.25%, about 2.26%, about 2.27%, about 2.28%, about 2.29%, about 2.3%, about 2.31%, about 2.3%. 32%, about 2.33%, about 2.34%, about 2.35%, about 2.36%, about 2.37%, about 2.38%, about 2.39%, about 2.4% , about 2.41%, about 2.42%, about 2.43% , about 2.44%, about 2.45%, about 2.46%, about 2.47%, about 2.48%, about 2.49%, or about 2.5% Mg . All percentages are expressed in weight percent.

In some examples, the disclosed alloys contain about 0.5% to about 1.5% (eg, about 0.6% to about 1.0% or about 0.6%) based on the total weight of the alloy. % to about 0.9%) of copper (Cu). For example, the alloy may contain about 0.5%, about 0.51%, about 0.52%, about 0.53%, about 0.54%, about 0.55%, about 0.56%, about 0.56%. 57%, about 0.58%, about 0.59%, about 0.6%, about 0.61%, about 0.62%, about 0.63%, about 0.64%, about 0.65% , about 0.66%, about 0.67%, about 0.68%, about 0.69%, about 0.7%, about 0.71%, about 0.72%, about 0.73%, about 0.74%, about 0.75%, about 0.76%, about 0.77%, about 0.78%, about 0.79%, about 0.8%, about 0.81%, about 0.79%. 82%, about 0.83%, about 0.84%, about 0.85%, about 0.86%, about 0.87%, about 0.88%, about 0.89%, about 0.9% , about 0.91%, about 0.92%, about 0.93%, about 0.94%, about 0.95%, about 0.96%, about 0.97%, about 0.98%, about 0.99%, about 1.0%, about 1.01%, about 1.02%, about 1.03%, about 1.04%, about 1.05%, about 1.06%, about 1.0% 07%, about 1.08%, about 1.09%, about 1.1%, about 1.11%, about 1.12%, about 1.13%, about 1.14%, about 1.15% , about 1.16%, about 1.17%, about 1.18%, about 1.19%, about 1.2%, about 1.21%, about 1.22%, about 1.23%, about 1.24%, about 1.25%, about 1.26%, about 1.27%, about 1.28%, about 1.29%, about 1.3%, about 1.31%, about 1.3%. 32%, about 1.33%, about 1.34%, about 1.35%, about 1.36%, about 1.37%, about 1.38%, about 1.39%, about 1.4% , about 1.41%, about 1.42%, about 1.43%, about 1.44%, about 1.45%, about 1.46%, about 1.47%, about 1.48%, about It may contain 1.49%, or about 1.5% Cu. All percentages are expressed in weight percent.

In some examples, the alloys described herein contain up to about 3.0% (eg, from about 1.0% to about 3.0%, from about 1.5% to about 3.0%, or about 2.0% to about 3.0%) of zinc (Zn). For example, the alloy may contain about 0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%, about 0.07%, about 0.07%. 08%, about 0.09%, about 0.1%, about 0.11%, about 0.12%, about 0.13%, about 0.14%, about 0.15%, about 0.16% , about 0.17%, about 0.18%, about 0.19%, about 0.2%, about 0.21%, about 0.22%, about 0.23%, about 0.24%, about 0.25%, about 0.26%, about 0.27%, about 0.28%, about 0.29%, about 0.3%, about 0.31%, about 0.32%, about 0.3%. 33%, about 0.34%, about 0.35%, about 0.36%, about 0.37%, about 0.38%, about 0.39%, about 0.4%, about 0.41% , about 0.42%, about 0.43%, about 0.44%, about 0.45%, about 0.46%, about 0.47%, about 0.48%, about 0.49%, about 0.5%, about 0.51%, about 0.52%, about 0.53%, about 0.54%, about 0.55%, about 0.56%, about 0.57%, about 0.5%. 58%, about 0.59%, about 0.6%, about 0.61%, about 0.62%, about 0.63%, about 0.64%, about 0.65%, about 0.66% , about 0.67%, about 0.68%, about 0.69%, about 0.7%, about 0.71%, about 0.72%, about 0.73%, about 0.74%, about 0.75%, about 0.76%, about 0.77%, about 0.78%, about 0.79%, about 0.8%, about 0.81%, about 0.82%, about 0.8%. 83%, about 0.84%, about 0.85%, about 0.86%, about 0.87%, about 0.88%, about 0.89%, about 0.9%, about 0.91% , about 0.92%, about 0.93%, about 0.94%, about 0.95%, about 0.96%, about 0.97%, about 0.98%, about 0.99%, about 1.0%, about 1.01%, about 1.02%, about 1.03%, about 1.04%, about 1.05%, about 1.06%, about 1.07%, about 1.0%. 08%, about 1.09%, about 1.1%, about 1.11%, about 1.12%, about 1.13%, about 1.14%, about 1.15%, about 1.16% , about 1.17%, about 1.18%, about 1.19%, about 1.2%, about 1.21%, about 1.22%, about 1.23%, about 1.24%, about 1.25%, about 1.26%, about 1.27%, about 1.28%, about 1.29%, about 1.3%, about 1.31%, about 1.32%, about 1.3%. 33%, about 1.34%, about 1.35%, about 1.36%, about 1.37%, about 1.38%, about 1.39%, about 1.4%, about 1.41% , about 1.42%, about 1.43%, about 1.44 %, about 1.45%, about 1.46%, about 1.47%, about 1.48%, about 1.49%, about 1.5%, about 1.51%, about 1.52%, about 1.53%, about 1.54%, about 1.55%, about 1.56%, about 1.57%, about 1.58%, about 1.59%, about 1.6%, about 1 .61%, about 1.62%, about 1.63%, about 1.64%, about 1.65%, about 1.66%, about 1.67%, about 1.68%, about 1.69 %, about 1.7%, about 1.71%, about 1.72%, about 1.73%, about 1.74%, about 1.75%, about 1.76%, about 1.77%, about 1.78%, about 1.79%, about 1.8%, about 1.81%, about 1.82%, about 1.83%, about 1.84%, about 1.85%, about 1 .86%, about 1.87%, about 1.88%, about 1.89%, about 1.9%, about 1.91%, about 1.92%, about 1.93%, about 1.94 %, about 1.95%, about 1.96%, about 1.97%, about 1.98%, about 1.99%, about 2.0%, about 2.01%, about 2.02%, about 2.03%, about 2.04%, about 2.05%, about 2.06%, about 2.07%, about 2.08%, about 2.09%, about 2.1%, about 2 .11%, about 2.12%, about 2.13%, about 2.14%, about 2.15%, about 2.16%, about 2.17%, about 2.18%, about 2.19 %, about 2.2%, about 2.21%, about 2.22%, about 2.23%, about 2.24%, about 2.25%, about 2.26%, about 2.27%, about 2.28%, about 2.29%, about 2.3%, about 2.31%, about 2.32%, about 2.33%, about 2.34%, about 2.35%, about 2 .36%, about 2.37%, about 2.38%, about 2.39%, about 2.4%, about 2.41%, about 2.42%, about 2.43%, about 2.44 %, about 2.45%, about 2.46%, about 2.47%, about 2.48%, about 2.49%, about 2.5%, about 2.51%, about 2.52%, about 2.53%, about 2.54%, about 2.55%, about 2.56%, about 2.57%, about 2.58%, about 2.59%, about 2.6%, about 2 .61%, about 2.62%, about 2.63%, about 2.64%, about 2.65%, about 2.66%, about 2.67%, about 2.68%, about 2.69 %, about 2.7%, about 2.71%, about 2.72%, about 2.73%, about 2.74%, about 2.75%, about 2.76%, about 2.77%, about 2.78%, about 2.79%, about 2.8%, about 2.81%, about 2.82%, about 2.83%, about 2.84%, about 2.85%, about 2 .86%, about 2.87%, about 2.88%, about 2.8 9%, about 2.9%, about 2.91%, about 2.92%, about 2.93%, about 2.94%, about 2.95%, about 2.96%, about 2.97% , about 2.98%, about 2.99%, or about 3.0% Zn. In some cases, Zn is not present in the alloy (ie 0%). All percentages are expressed in weight percent.

Optionally, zirconium (Zr) can be included in the alloys described herein. In some examples, the alloy contains up to about 0.15% (eg, about 0.07% to about 0.15%, about 0.09% to about 0.12%, or about 0.08% to about 0.11%). For example, the alloy may contain about 0.01%, about 0.02%, about 0.03%, about 0.04%, about 0.05%, about 0.06%, about 0.07%, about 0.07%. 08%, about 0.09%, about 0.1%, about 0.11%, about 0.12%, about 0.13%, about 0.14%, or about 0.15% Zr can be done. In some examples, Zr is absent (ie, 0%) in the alloy. All percentages are expressed in weight percent. In certain aspects, Zr is added to the composition to form (Al _, Si) _3Zr dispersoids (DO22/ _DO23 dispersoids) and/or _Al3Zr dispersoids ₍ L12 dispersoids) .

Optionally, the alloy composition contains no more than about 0.05%, no more than 0.04%, no more than 0.03%, no more than 0.02% each of other trace elements, sometimes referred to as impurities. , or in an amount of 0.01% or less. These impurities include, but are not limited to Ga, V, Ni, Sc, Ag, B, Bi, Li, Pb, Sn, Ca, Cr, Ti, Hf, Sr, or combinations thereof. Therefore, Ga, V, Ni, Sc, Ag, B, Bi, Li, Pb, Sn, Ca, Cr, Ti, Hf, or Sr is 0.05% or less, 0.04% or less, It may be present in an amount of 0.03% or less, 0.02% or less, or 0.01% or less. In certain aspects, the sum of all impurities does not exceed 0.15% (eg, 0.1%). All percentages are expressed in weight percent. In certain embodiments, the remaining proportion of the alloy is aluminum.

Suitable exemplary alloys are, for example, 1.0% Si, 2.0%-2.25% Mg, 0.6%-0.7% Cu, 2.5%-3.0% Zn, 0.07-0.10% Mn, 0.14-0.17% Fe, 0.09-0.10% Zr, and up to 0.15% total impurities, balance Al can contain. In some cases, a suitable exemplary alloy is 0.55%-0.65% Si, 1.5% Mg, 0.7%-0.8% Cu, 1.55% Zn, May contain 0.14-0.15% Mn, 0.16-0.18% Fe, and up to 0.15% total impurities, balance Al. In some cases, a suitable exemplary alloy is 0.65% Si, 1.5% Mg, 1.0% Cu, 2.0%-3.0% Zn, 0.14-0 .15% Mn, 0.17% Fe, and up to 0.15% total impurities, balance Al.

Alloy Microstructure and Properties In certain embodiments, the ratio of Cu, Mg, and Si and Zn content are controlled to improve corrosion resistance, strength, and formability. Zn content can control corrosion morphology, for example, by inducing pitting corrosion and suppressing intergranular corrosion (IGC), as described below.

In some examples, the ratio of Mg to Si (also referred to herein as the Mg/Si ratio) is from about 1.5:1 to about 3.5:1 (eg, from about 1.75:1 to about 3 .0:1 or from about 2.0:1 to about 3.0:1). For example, the Mg/Si ratio is about 1.5:1, about 1.6:1, about 1.7:1, about 1.8:1, about 1.9:1, about 2.0:1, about 2.1:1, about 2.2:1, about 2.3:1, about 2.4:1, about 2.5:1, about 2.6:1, about 2.7:1, about 2.8:1, about 2.9:1, about 3.0:1, about 3.1:1, about 3.2:1, about 3.3:1, about 3.4:1, about 3 .5:1, about 3.6:1, about 3.7:1, about 3.8:1, about 3.9:1, or about 4.0:1. In some non-limiting examples, an aluminum alloy having a Mg/Si ratio of about 1.5:1 to about 3.5:1 (eg, about 2.0:1 to about 3.0:1) is , can exhibit high strength and increased formability.

In some non-limiting examples, an aluminum alloy having a Mg/Si ratio of about 2.0:1 to 3.0:1 and a Zn content of about 2.5% to about 3.0% by weight is , can suppress the IGC typically observed in aluminum alloys with Mg and Si as major alloying elements, and can instead induce pitting corrosion. In some cases, pitting may be preferred over IGC due to its limited depth of attack, as IGC can occur along grain boundaries and propagate deeper into aluminum alloys than pitting. . In some non-limiting examples, the ratio of Zn to Mg/Si ratio (i.e., Zn/(Mg/Si) ratio) is from about 0.75:1 to about 1.4:1 (e.g., about 0 .8:1 to about 1.1:1). For example, the Zn/(Mg/Si) ratio can be about 0.75:1, about 0.8:1, about 0.85:1, about 0.9:1, about 0.95:1, about 1.5:1, about 0.95:1, about 1.5:1, about 0.95:1, about 0.95:1. 0:1, about 1.05:1, about 1.1:1, about 1.15:1, about 1.2:1, about 1.25:1, about 1.3:1, about 1.35 :1, or about 1.4:1.

In some still further non-limiting examples, the ratio of Cu to Zn/(Mg/Si) ratio (i.e., Cu/[Zn/(Mg/Si)] ratio) is from about 0.7:1 to about 1.4:1 (eg, the Cu/[Zn/(Mg/Si)] ratio can be from about 0.8:1 to about 1.1:1). For example, the Cu/[Zn/(Mg/Si)] ratio is about 0.7:1, about 0.75:1, about 0.8:1, about 0.85:1, about 0.9: 1, about 0.95:1, about 1.0:1, about 1.05:1, about 1.1:1, about 1.15:1, about 1.2:1, about 1.25:1 , about 1.3:1, about 1.35:1, or about 1.4:1. In some non-limiting examples, a ratio of Cu/[Zn/(Mg/Si)] can provide high strength, high deformability, and high corrosion resistance.

In certain aspects, Cu, Si, and Mg can form precipitates in the alloy, resulting in alloys with higher strength and enhanced corrosion resistance. These precipitates may form during the aging process after solution treatment. The content of Mg and Cu can lead to precipitation of M/η phase or M phase (e.g. MgZn ₂ /Mg(Zn,Cu) ₂ ), resulting in precipitates that increase the strength of the aluminum alloy. can be increased. During the precipitation process, metastable Guinnie-Preston (GP) zones can form, which are β″ acicular precipitates (e.g., magnesium silicide, Mg ₂ Si) that contribute to precipitation strengthening of the disclosed alloys. ) sequentially. _In certain aspects, the addition of Cu results in the formation of lathe _- shaped L-phase precipitates ₍ e.g., _Al4Mg8Si7Cu2 ), which are precursors to the Q' precipitate phase formation, further contributing to strength. .

In some examples, the M-phase precipitates comprising _MgZn2 and/or Mg(Zn,Cu) ₂ are present in the aluminum alloy in an amount of an average of at least about 300,000,000 particles per square millimeter ( ^mm2 ). can exist in For example, the M-phase precipitates are at least about 310,000,000 particles/ ^mm2 , at least about 320,000,000 particles/ ^mm2 , at least about 330,000,000 particles/ ^mm2 , at least about 340,000, 000 particles/ ^mm2 , at least about 350,000,000 particles/ ^mm2 , at least about 360,000,000 particles/ ^mm2 , at least about 370,000,000 particles/ ^mm2 , at least about 380,000,000 particles /mm ² , at least about 390,000,000 particles/mm ² , or at least about 400,000,000 particles/mm ² .

In some examples, the L _- phase precipitates comprising _{Al4Mg8Si7Cu2 are} present _in the aluminum alloy in an amount of an average of at least about 600,000,000 particles per square millimeter ( ^mm2 ). be able to. For example, the L-phase precipitates are at least about 610,000,000 particles/ ^mm2 , at least about 620,000,000 particles/ ^mm2 , at least about 630,000,000 particles/ ^mm2 , at least about 640,000, 000 particles/ ^mm2 , at least about 650,000,000 particles/ ^mm2 , at least about 660,000,000 particles/ ^mm2 , at least about 670,000,000 particles/ ^mm2 , at least about 680,000,000 particles /mm ² , at least about 690,000,000 particles/mm ² , or at least about 700,000,000 particles/mm ² .

In some examples, the β″ phase precipitates comprising Mg ₂ Si can be present in the aluminum alloy in an amount of at least an average of about 600,000,000 particles per square millimeter (mm ² ). For example, the β″ phase precipitates are at least about 610,000,000 particles/mm ² , at least about 620,000,000 particles/mm ² , at least about 630,000,000 particles/mm ² , at least about 640, 000,000 particles/mm2, at least about 650,000,000 particles/ ^mm2 , at least about 660,000,000 particles/ ^mm2 , at least about 670,000,000 particles/ ^mm2 , at ^least about 680,000, 000 particles/ ^mm2 , at least about 690,000,000 particles/ ^mm2 , at least about 700,000,000 particles/ ^mm2 , at least about 710,000,000 particles/ ^mm2 , at least about 720,000,000 particles /mm ² , at least about 730,000,000 particles/mm ² , at least about 740,000,000 particles/mm ² , or at least about 750,000,000 particles/mm ² .

In some examples, the ratio of β″ phase precipitates (eg, Mg ₂ Si) to L phase precipitates (eg, Al ₄ Mg ₈ Si ₇ Cu ₂ ) is from about 1:1 to about 1.5:1. (eg, from about 1.1:1 to about 1.4:1).For example, the ratio of β″ phase precipitates to L phase precipitates is about 1:1, about 1.1:1 , about 1.2:1, about 1.3:1, about 1.4:1, or about 1.5:1.

In some examples, the ratio of β″ phase precipitates (eg, Mg ₂ Si) to M phase precipitates (eg, MgZn ₂ and/or Mg(Zn,Cu) ₂ ) is from about 1.5:1 to can be about 3:1 (eg, about 1.6:1 to about 2.8:1 or about 2.0:1 to about 2.5:1). The phase precipitate ratios are about 1.5:1, about 1.6:1, about 1.7:1, about 1.8:1, about 1.9:1, about 2.0:1, about 2.1:1, about 2.2:1, about 2.3:1, about 2.4:1, about 2.5:1, about 2.6:1, about 2.7:1, about 2 .8:1, about 2.9:1, or about 3.0:1.

In some examples, the ratio of L-phase precipitates (eg, Al ₄ Mg ₈ Si ₇ Cu ₂ ) to M-phase precipitates (eg, MgZn ₂ and/or Mg(Zn,Cu) ₂ ) is about 1.5. 5:1 to about 3:1 (eg, about 1.6:1 to about 2.8:1 or about 2.0:1 to about 2.5:1). For example, the ratio of L-phase to M-phase precipitates is about 1.5:1, about 1.6:1, about 1.7:1, about 1.8:1, about 1.9:1, about 2.0:1, about 2.1:1, about 2.2:1, about 2.3:1, about 2.4:1, about 2.5:1, about 2.6:1, about It can be 2.7:1, about 2.8:1, about 2.9:1, or about 3.0:1.

The alloys described herein exhibit exceptional mechanical properties, as provided further below. The mechanical properties of aluminum alloys can be further controlled by various aging conditions, depending on the desired use. As an example, the alloy can be produced (or provided) with a T4 temper or a T6 temper. A T4 aluminum alloy product can be provided that is solution heat treated and naturally aged. These T4 aluminum alloy products may optionally be subjected to additional aging treatment(s) to meet strength requirements upon receipt. For example, an aluminum alloy product can be delivered in other tempers, such as a T6 temper, by subjecting the T4 alloy material to the appropriate aging treatment described herein or known to those skilled in the art. . Exemplary properties for exemplary tempering degrees are provided below.

In certain aspects, the aluminum alloy can have a yield strength of at least about 340 MPa at a T6 temper. In non-limiting examples, the yield strength can be at least about 350 MPa, at least about 360 MPa, or at least about 370 MPa. In some cases, the yield strength is from about 340 MPa to about 400 MPa. For example, the yield strength can be from about 350 MPa to about 390 MPa, or from about 360 MPa to about 380 MPa.

In certain aspects, the aluminum alloy can have an ultimate tensile strength of at least about 400 MPa at a T6 temper. In non-limiting examples, the ultimate tensile strength can be at least about 410 MPa, at least about 420 MPa, or at least about 430 MPa. In some cases, the ultimate tensile strength is from about 400 MPa to about 450 MPa. For example, the ultimate tensile strength can be from about 410 MPa to about 440 MPa, or from about 415 MPa to about 435 MPa.

In certain aspects, the aluminum alloy has sufficient ductility or toughness to meet a 90° bendability of 1.0 or less (eg, 0.5 or less) at the T4 temper. In certain examples, the r/t bendability ratio is about 1.0 or less, about 0.9 or less, about 0.8 or less, about 0.7 or less, about 0.6 or less, about 0.5 or less, about 0.4 or less, about 0.3 or less, about 0.2 or less, or about 0.1 or less, where r is the radius of the tool (die) used and t is the thickness of the material.

In certain aspects, the aluminum alloy exhibits a uniform elongation of 20% or greater at the T4 temper and a total elongation of 30% or greater at the T4 temper. In certain embodiments, the alloy exhibits a uniform elongation of 22% or greater and a total elongation of 35% or greater. For example, the alloy can exhibit a uniform elongation of 20% or greater, 21% or greater, 22% or greater, 23% or greater, 24% or greater, 25% or greater, 26% or greater, 27% or greater, or 28% or greater. The alloy has a uniform elongation of 30% or more, 31% or more, 32% or more, 33% or more, 34% or more, 35% or more, 36% or more, 37% or more, 38% or more, 39% or more, or 40% or more. can be shown.

In certain aspects, the aluminum alloy exhibits suitable resistance to IGC as measured by ISO 11846B. For example, pitting corrosion in aluminum alloys can be completely suppressed or ameliorated such that the alloy's average intergranular corrosion pitting depth at T6 temper is less than 100 μm. For example, the average intergranular corrosion pit depth can be less than 90 μm, less than 80 μm, less than 70 μm, less than 60 μm, less than 50 μm, or less than 40 μm.

Methods of Preparing Aluminum Alloys In certain aspects, the disclosed alloy compositions are products of the disclosed methods. Although not intended to limit the present disclosure, the properties of aluminum alloys are determined in part by the formation of microstructures during alloy preparation. In certain embodiments, the method of preparation of the alloy composition can affect or even determine whether the alloy has suitable properties for a desired application.

Casting The alloys described herein can be cast using casting methods. In some non-limiting examples, the aluminum alloys described herein can be cast from molten aluminum alloys, including scrap alloys (e.g., AA6xxx series aluminum alloy scrap, AA7xxx series aluminum alloy scrap, or from a combination of ). The casting process can include a direct chill (DC) casting process. Optionally, the ingot can be scalped prior to downstream processing. Optionally, the casting process can include a continuous casting (CC) process. The cast aluminum alloy can then be subjected to further processing steps. For example, the processing methods described herein can include the steps of homogenization, hot rolling, solution heat treatment, and quenching. In some cases, the processing method can also include pre-aging and/or artificial aging steps.

Homogenization The homogenization step heats an ingot prepared from an alloy composition described herein to about or at least about 500°C (e.g., at least 520°C, at least 530°C, at least 540°C, at least 550°C). , at least 560° C., at least 570° C., or at least 580° C.). For example, the ingot can be heated from about 500° C. to about 600° C., from about 520° C. to about 580° C., from about 530° C. to about 575° C., from about 535° C. to about 570° C., from about 540° C. to about 565° C., from about 545° C. to about It can be heated to a temperature of 560°C, from about 530°C to about 560°C, or from about 550°C to about 580°C. In some cases, the heating rate to the PMT is about 70° C./hour or less, 60° C./hour or less, 50° C./hour or less, 40° C./hour or less, 30° C./hour or less, 25° C./hour or less; It can be 20° C./hour or less, or 15° C./hour or less. In other cases, the heating rate to the PMT is from about 10° C./min to about 100° C./min (eg, from about 10° C./min to about 90° C./min, from about 10° C./min to about 70° C./min. , from about 10° C./min to about 60° C./min, from about 20° C./min to about 90° C./min, from about 30° C./min to about 80° C./min, from about 40° C./min to about 70° C./min, or from about 50° C./min to about 60° C./min).

The ingot is then immersed (ie held at the indicated temperature) for a period of time. According to one non-limiting example, the ingot can be soaked for up to about 6 hours (eg, about 30 minutes to about 6 hours, inclusive). For example, the ingot can be soaked at a temperature of at least 500° C. for 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, or any time therebetween.

Hot Rolling After the homogenization step, a hot rolling step can be performed to form a hot band. In certain cases, the ingot is placed and hot rolled at an exit temperature ranging from about 230°C to about 300°C (eg, from about 250°C to about 300°C). For example, hot roll exit temperatures are about 230°C, about 235°C, about 240°C, about 245°C, about 250°C, about 255°C, about 260°C, about 265°C, about 270°C, about 275°C, about 280°C. °C, about 285°C, about 290°C, about 295°C, or about 300°C.

In certain cases, the ingot can be hot rolled to a thickness gauge of about 4 mm to about 15 mm (eg, a thickness gauge of about 5 mm to about 12 mm). For example, the ingot has a thickness gauge of about 4 mm, a thickness gauge of about 5 mm, a thickness gauge of about 6 mm, a thickness gauge of about 7 mm, a thickness gauge of about 9 mm, a thickness gauge of about 9 mm, and a thickness gauge of about 10 mm. It can be hot rolled to a thickness gauge, about 11 mm thickness gauge, about 12 mm thickness gauge, about 13 mm thickness gauge, about 14 mm thickness gauge, or about 15 mm thickness gauge. In certain cases, ingots can be hot rolled to gauges (eg, plate gauges) greater than 15 mm thick. In another example, the ingot can be hot rolled to a gauge of less than 4 mm (ie sheet gauge).

Solution Heat Treatment Following the hot rolling step, the hot band may be cooled with air and then solutionized in a solution heat treatment step. The solution heat treatment converts the final gauge aluminum alloy from room temperature to about 520°C to about 590°C (e.g. to about 570°C, about 555°C to about 565°C, about 540°C to about 560°C, about 560°C to about 580°C, or about 550°C to about 575°C). . The final gauge aluminum alloy can be soaked at that temperature for a period of time. In certain aspects, the final gauge aluminum alloy can be soaked for up to about 2 hours (eg, about 10 seconds to about 120 minutes, inclusive). For example, the final gauge aluminum alloy is , 90 seconds, 95 seconds, 100 seconds, 105 seconds, 110 seconds, 115 seconds, 120 seconds, 125 seconds, 130 seconds, 135 seconds, 140 seconds, 145 seconds, 150 seconds, 5 minutes, 10 minutes, 15 minutes, 20 seconds minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes, 65 minutes, 70 minutes, 75 minutes, 80 minutes, 85 minutes, 90 minutes, 95 minutes, 100 minutes, It can be soaked at a temperature of about 525° C. to about 590° C. for 105 minutes, 110 minutes, 115 minutes, or 120 minutes, or any time therebetween.

Quenching In certain embodiments, the final gauge aluminum alloy is then subjected to a temperature of about 35° C. at a quenching rate that can vary between about 50° C./s and 400° C./s in a quenching step based on the gauge selected. can be cooled to For example, the quenching rate can be from about 50° C./s to about 375° C./s, from about 60° C./s to about 375° C./s, from about 70° C./s to about 350° C./s, from about 80° C./s to about 325° C./s. °C/s, about 90°C/s to about 300°C/s, about 100°C/s to about 275°C/s, about 125°C/s to about 250°C/s, about 150°C/s to about 225°C/s seconds, or from about 175° C./s to about 200° C./s.

In the quenching step, the final gauge aluminum alloy is rapidly quenched with a liquid (eg water) and/or gas or another selected quenching medium. In certain embodiments, the final gauge aluminum alloy can be rapidly quenched with water.

Pre-Aging Optionally, a pre-aging step can be performed. The pre-aging step cools the final gauge aluminum alloy after the quenching step to about 100°C to about 160°C (e.g., about 105°C to about 155°C, about 110°C to about 150°C, about 115°C to about 145°C, heating to a temperature of about 120° C. to about 140° C., or about 125° C. to about 135° C.). In certain aspects, the aluminum alloy sheet, plate, or sheet is heated for up to about 3 hours (e.g., up to about 10 minutes, up to about 20 minutes, up to about 30 minutes, up to about 40 minutes, up to about 45 minutes, up to about 60 minutes). minutes, up to about 90 minutes, up to about 2 hours, or up to about 3 hours).

Aging Final gauge aluminum alloys can be naturally aged or artificially aged. In some examples, the final gauge aluminum alloy can be naturally aged for a period of time to a T4 temper. In certain embodiments, the final gauge aluminum alloy at T4 temper is about 180°C to 225°C (e.g., 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, or 225° C.) for a period of time. Optionally, the final gauge aluminum alloy is aged from about 15 minutes to about 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 any time therebetween) to a T6 temper.

Uses The alloys and methods described herein can be used in automotive, electronic, and transportation applications, such as commercial vehicle, aircraft, or railroad applications, or other applications. For example, the alloys can be used in chassis, cross members, and internal chassis components (including but not limited to all components between two C-channels in a commercial vehicle chassis) to provide strength. , serves as a full or partial replacement for high-strength steel. In certain examples, alloys can be used in T4 and T6 tempers.

In certain embodiments, the alloys and methods can be used to prepare automotive body part products. For example, the disclosed alloys and methods can be used for bumpers, side beams, roof beams, cross beams, pillar reinforcements (e.g., A-pillars, B-pillars, and C-pillars), interior panels, side panels, floor panels, tunnels, structures It can be used to prepare automotive body parts such as panels, reinforcement panels, inner hoods or trunk lid panels. The disclosed aluminum alloys and methods can also be used to prepare, for example, exterior and interior panels in aircraft or rail vehicle applications. In certain aspects, the disclosed alloys may be used in other specialty applications such as automotive battery plates/sate.

For example, the alloys and methods described herein can also be used to prepare housings for electronic devices such as mobile phones and tablet computers. For example, the alloy, with or without anodization, can be used to prepare housings for the outer casings of mobile phones (eg, smartphones) and tablet bottom chassis. The alloys can also be used to prepare other consumer electronics and product parts. Exemplary consumer electronics include mobile phones, audio devices, video devices, cameras, laptop computers, desktop computers, tablet computers, televisions, displays, consumer electronics, video playback and recording devices, and the like. Exemplary consumer electronics components include outer housings (eg, facades) and inner components for consumer electronics.

The following examples serve to further illustrate the invention without, however, limiting it. On the contrary, it should be clearly understood that one can resort to various embodiments, modifications and equivalents, which may suggest themselves to those skilled in the art after reading the description herein without departing from the spirit of the invention. . During the studies described in the examples below, conventional procedures were followed unless otherwise stated. For illustrative purposes, some of the procedures are described below.

Example 1 Aluminum Alloy Composition Tables 4A and 4B below summarize exemplary aluminum alloys, and Table 5 provides yield strength (YS), intergranular corrosion pitting depth (IGC), and 90 ° Shows alloy properties including bendability (bending).

Alloy properties were achieved by controlling the proportions of the alloying elements. Alloy 1 represents a comparative AA6xxx series aluminum alloy that exhibits high strength due to Mg ₂ Si strengthening precipitates in the aluminum alloy. Alloy 2 is a comparative aluminum alloy in which the addition of Zn improves corrosion resistance and slightly reduces strength. Alloys 1 and 2, which do not have a Cu/[Zn/(Mg/Si)] ratio in the range of about 0.7 to about 1.4, show significant IGC and failure in the 90° bend test. Alloy 3 represents an exemplary aluminum alloy with a Cu/[Zn/(Mg/Si)] ratio closer to the range of about 0.7 to about 1.4 than Alloy 2, providing excellent formability and It exhibits reduced strength along with IGC resistance. Alloy 4 has a Cu/[Zn/(Mg/Si)] ratio in the range of about 0.7 to about 1.4, but a Zn/(Mg/Si) ratio of about 0.75 to about Figure 3 depicts an exemplary aluminum alloy not within the range of 1.4, showing significant IGC and poor formability and increased strength when compared to Alloy 3; Alloy 5 represents an exemplary aluminum alloy with Mg/Si, Zn/(Mg/Si), and Cu/[Zn/(Mg/Si)] ratios all within their respective ranges, resulting in high strength , good moldability, and good corrosion resistance.

Additionally, exemplary alloys were produced according to the direct chill casting method described herein. The alloy compositions are summarized in Table 6 below.

Example 2: Microstructure of Aluminum Alloys An exemplary alloy was produced by direct chill casting and processed according to the methods described herein. As mentioned above, the content of Mg and Cu can prepare M-phase precipitates (e.g., _MgZn2 /Mg(Zn,Cu) ₂ ), which can increase the strength of aluminum alloys. prepare things. Evaluation of M-phase (eg, MgZn ₂ ) precipitates was made as a function of Mg content in exemplary alloys. FIG. 1 is a graph showing that the Mg content was increased from 1.0 wt% to 3.0 wt%. As is evident from the graph, the mass fraction of M-phase precipitates (i) increases proportionally as the Mg content increases from 1.0 wt% to 1.5 wt%, and (ii) Mg (iii) remains constant as the content increases from 1.5 wt% to 2.0 wt% and increases proportionally as the Mg content increases from 2.0 wt% to 2.5 wt% and (iv) a plateau occurs when the Mg content exceeds 2.5% by weight. An increase in M-phase precipitates increases the strength of the exemplary alloy.

FIG. 2 is a graph showing differential scanning calorimetry (DSC) analysis of the exemplary alloy 3 samples (designated "H1", "H2", and "H3") described above. Exothermic peak A indicates precipitate formation in the exemplary alloy and endothermic peak B indicates the melting point of exemplary alloy 3 sample.

FIG. 3 is a graph showing the DSC analysis of the above exemplary alloy 5 samples (designated "H5,""H6," and "H7"). Exothermic peak A indicates M-phase precipitates. Exothermic peak B indicates the formation of strengthening precipitates during the artificial aging step and indicates β″ (Mg ₂ Si) precipitates corresponding to the increase in strength of the exemplary aluminum alloy. C indicates the melting point of the exemplary Alloy 5 sample.

FIG. 4A is a transmission electron microscope (TEM) showing three distinct strengthening precipitation _phases , M( _MgZn2 ) 410, β″( _Mg2Si ) 420, and L _{( Al4Mg8Si7Cu2} ) ₄₃₀ . Figure 4B is a TEM showing Zr-containing precipitate particles 440, with a combination of three precipitate phases providing a yield strength of about 370 MPa at a T6 temper for a 10 mm gauge aluminum alloy (e.g. Alloy 5). 4 is a micrograph Excess Zr in exemplary alloys can cause the formation of coarse acicular particles, coarse acicular Zr-containing precipitation particles 440 can reduce the formability of exemplary alloys. Too little Zr in exemplary alloys may not provide the desired Al ₃ Zr and/or (Al,Si) ₃ Zr dispersoids.

Figure ₅ shows the density of each distinct strengthening precipitate phase, namely M _{( MgZn2} ), L _{( Al4Mg8Si7Cu2} ), and β'' (Mg2Si) per _square millimeter. 2 is a graph showing the number of precipitated grains (#/mm ² ) of and as a percentage of the analyzed area occupied in Alloy C by each distinct precipitated phase (see Table 6). The β″ precipitates, due to their shape, dominate in both density and area. Therefore, the smaller M and L precipitates occupy less area and are present at densities comparable to the β″ precipitates.

FIG. 6 shows an optical micrograph of a sample of alloy 3 as described above. Precipitates were analyzed in as-cast samples (top), homogenized samples (middle), and hot-rolled samples reduced to 10 mm gauge (bottom). Precipitates of the eutectic phase were clearly observed in the as-cast samples. The precipitate did not completely dissolve after homogenization, as shown in the middle row of the micrograph. Coarse (eg, greater than about 5 microns) precipitates were clearly visible in the hot rolled samples.

FIG. 7 shows a sample of Alloy 3 above after various solution heat treatment procedures to achieve maximum dissolution of strengthening precipitates during casting, homogenization, hot rolling to 10 mm gauge, and solution heat treatment. Optical micrographs are shown. FIG. 7, panel A, shows alloy 3 samples solutionized at a temperature of 555° C. for 45 minutes. FIG. 7, panel B, shows alloy 3 samples solutionized at a temperature of 350° C. for 45 minutes, then at a temperature of 500° C. for 30 minutes, and finally at a temperature of 565° C. for 30 minutes. FIG. 7, panel C, shows alloy 3 samples solutionized at a temperature of 350° C. for 45 minutes, then at a temperature of 500° C. for 30 minutes, and finally at a temperature of 565° C. for 60 minutes. FIG. 7, panel D, shows alloy 3 samples solution annealed at a temperature of 560° C. for 120 minutes. FIG. 7, panel E, shows alloy 3 samples solutionized at a temperature of 500° C. for 30 minutes and then at a temperature of 570° C. for 30 minutes. FIG. 7, Panel F, shows alloy 3 samples solutionized at a temperature of 500° C. for 30 minutes and then at a temperature of 570° C. for 60 minutes.

FIG. 8 shows an optical micrograph of a sample of alloy 5 as described above. Precipitates were analyzed on as-cast samples (top) and homogenized samples (bottom). Precipitates of the eutectic phase were clearly observed in the as-cast samples. The precipitate did not completely dissolve after homogenization, as seen in the bottom row of the micrographs. However, Alloy 5 had less undissolved precipitates compared to Alloy 3 after homogenization due to changes in solute levels (eg, Mg level, Si level, and Mg/Si ratio).

FIG. 9 shows an optical micrograph of a sample of Alloy 5 above after hot rolling to 10 mm gauge. FIG. 9, panels A, B, and C, show precipitated grains (visible as black dots) in exemplary alloy samples after hot rolling to 10 mm gauge. FIG. 9, panels D, E, and F, show the grain structure after hot rolling an exemplary alloy 5 sample to a gauge of 10 mm. Due to the low hot rolling exit temperature of about 280°C to about 300°C, the grains were not completely recrystallized.

FIG. 10 shows an optical micrograph of a sample of Alloy 5 above after hot rolling to 10 mm gauge, solution heat treatment, and natural aging with T4 temper. FIG. 10, panels A, B, and C show very few precipitated particles in the exemplary alloy sample at T4 temper. FIG. 10, panels D, E, and F show the fully recrystallized grain structure of exemplary Alloy 5 sample at T4 temper.

FIG. 11 is a graph showing the conductivity of alloy 3 samples after casting, homogenization, hot rolling, various solution heat treatment procedures, and artificial aging (AA). Conductivity data (ie, conductivity as a percentage of the International Annealed Copper Standard (%IACS)) show a large amount of precipitates after hot rolling. Various solution heat treatment procedures were evaluated in an attempt to dissolve the precipitates. Solution heat treatment was not effective in dissolving the precipitates. Moreover, there was insufficient strengthening precipitate formation during artificial aging to provide optimum strength.

FIG. 12 is a graph showing the conductivity of samples of Alloy 5 (designated "HR5," "HR6," and "HR7") after casting, homogenization, hot rolling, solution heat treatment, and artificial aging; be. Electrochemical test data show a large amount of precipitates after hot rolling. Various solution heat treatment procedures were evaluated in an attempt to dissolve the precipitates. The solution heat treatment was effective in dissolving the precipitates. Furthermore, artificial aging enhanced the formation of precipitates, resulting in optimum strength.

Example 3 Mechanical Properties of Aluminum Alloys FIG. 13 shows yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform It is a graph showing elongation (white circles) and total elongation (white diamonds). The alloy was solution heat treated at a temperature of 565°C for 45 minutes, pre-aged at a temperature of 125°C for 2 hours, and artificially aged at a temperature of 200°C for 4 hours to a T6 temper. Each alloy exhibited a yield strength greater than 370 MPa, an ultimate tensile strength greater than 425 MPa, a uniform elongation greater than 10%, and a total elongation greater than 17%. Increasing the Zn content did not significantly affect the strength of the exemplary aluminum alloy, but improved resistance to intergranular corrosion and formability.

FIG. 14A shows yield strength (left histogram of each set), ultimate tensile strength for exemplary alloy 3 samples with T4 temper (designated “H1 T4,” “H2 T4,” and “H3 T4”). (right histogram for each set), uniform elongation (open circles), and total elongation (open diamonds). FIG. 14B shows yield strength (left histogram of each set), ultimate tensile strength for exemplary Alloy 3 samples with T6 temper (designated “H1 T6,” “H2 T6,” and “H3 T6”). (right histogram for each set), uniform elongation (open circles), and total elongation (open diamonds).

FIG. 15 shows the yield rate for exemplary Alloy 3 samples (designated “H1,” “H2,” and “H3”) at T6 tempers after various aging procedures, as indicated on the x-axis of the graph. 5 is a graph showing strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles), and total elongation (open diamonds). As can be seen from the graph, the three-step aging treatment was able to produce high-strength (eg, 348 MPa) aluminum alloys. Also, as is evident from the graph, aging at low temperatures (eg, below 250° C.) was insufficient to form strengthening precipitates in the alloy samples.

FIG. 16A shows the yield strength (left histogram of each set), ultimate tensile Graph showing intensity (right histogram for each set), uniform elongation (open circles), and total elongation (open diamonds). FIG. 16B shows the yield strength (left histogram of each set), ultimate tensile Graph showing intensity (right histogram for each set), uniform elongation (open circles), and total elongation (open diamonds). As can be seen from the graph, a maximum strength of 360 MPa was achieved. Also, as is evident from the graph, aging at low temperatures (eg, below 250° C.) was insufficient to form strengthening precipitates in the alloy samples.

FIG. 17A shows exemplary Alloy 5 samples at T4 temper (“HR5,” “HR6,” after casting, homogenization, hot rolling to 10 mm gauge, solution heat treatment, and various annealing techniques). FIG. 10 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles), and total elongation (open diamonds) for each set (designated "HR7"). Air cooled samples are referred to as "AC" and water quenched samples are referred to as "WQ" after hot rolling. FIG. 17B shows exemplary Alloy 5 samples at T6 temper (“HR5,” “HR6,” after casting, homogenization, hot rolling to 10 mm gauge, solution heat treatment, and various annealing techniques. FIG. 10 is a graph showing yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles), and total elongation (open diamonds) for each set (designated "HR7"). Air cooled samples are referred to as "AC" and water quenched samples are referred to as "WQ" after hot rolling. Artificial aging to a T6 temper resulted in a high strength aluminum alloy with a yield strength of about 360 MPa to about 370 MPa.

FIG. 18A shows exemplary alloy 5 samples (referred to as “HR5,” “HR6,” and “HR7”) at T4 temper after casting, homogenization, hot rolling to 10 mm gauge, and solution heat treatment. ) for yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles), and total elongation (open diamonds). FIG. 18B shows an exemplary Alloy 5 sample at T6 temper (“HR5”) after casting, homogenization, hot rolling to 10 mm gauge, solution heat treatment, and various aging procedures as shown in the graph. , “HR6”, and “HR7”) are shown for yield strength (left histogram of each set), ultimate tensile strength (right histogram of each set), uniform elongation (open circles), and total elongation (open diamonds). graph. Artificial aging to a T6 temper resulted in a high strength aluminum alloy with a yield strength of about 360 MPa to about 370 MPa.

FIG. 19 is a graph showing load-displacement data for the 90° bend test formability of the above exemplary Alloy 5 samples (designated "HR5," "HR6," and "HR7"). Samples tested longitudinally to the rolling direction are indicated by "-L" and samples tested transverse to the rolling direction are indicated by "-T". Alloy 5 was prepared by casting, homogenizing, hot rolling to 10 mm gauge, solution heat treatment, and natural aging for 1 week to prepare Alloy 5 samples with T4 temper. The samples were subjected to a 90° bend test and the load displacement (left axis) and maximum load (right axis) were recorded.

FIG. 20 is a graph showing load-displacement data for the 90° bend test formability of the above exemplary Alloy 5 samples (designated "HR5," "HR6," and "HR7"). Samples tested longitudinally to the rolling direction are indicated by "-L" and samples tested transverse to the rolling direction are indicated by "-T". Alloy 5 was cast, homogenized, hot rolled to 10 mm gauge, solution heat treated, pre-aged at a temperature of 125° C. for 2 hours (referred to as “PX”), and naturally aged for 1 week to obtain a T4 temper. Five alloy samples were prepared. The samples were subjected to a 90° bend test and the load displacement (left axis) and maximum load (right axis) were recorded.

FIG. 21 is a graph showing load-displacement data for 90° bend test formability of exemplary Alloy 5 samples described above. Samples tested longitudinally to the rolling direction are indicated by "-L" and samples tested transverse to the rolling direction are indicated by "-T". The samples were prepared by casting, homogenizing, hot rolling to 10 mm gauge, solution heat treatment, pre-aging at a temperature of 125° C. for 2 hours, and natural aging for 1 month to prepare 5 alloy samples with T4 temper. The samples were subjected to a 90° bend test and the load displacement (left axis) and maximum load (right axis) were recorded. There was no significant change in formability from 1 week natural aging to 1 month natural aging with the pre-aging used during manufacture.

FIG. 22 is an optical micrograph showing the effect of corrosion testing on the above alloys. The alloy was subjected to corrosion testing according to ISO standard 11846B (eg, immersion in an aqueous solution containing 3.0% by weight sodium chloride (NaCl) and 1.0% by volume hydrochloric acid (HCl) for 24 hours). Figure 22, Panel A and Figure 22, Panel B show the effect of corrosion testing on Comparative Alloy 2 above. The corrosion mode is intergranular corrosion (IGC) attack. FIG. 22, panels C, D, and E show the effects of corrosion testing on exemplary Alloy 3 above. The form of corrosion is pitting. Pitting is a more desirable form of corrosion that is less damaging to the alloy and exhibits corrosion resistance in exemplary alloys.

FIG. 23 shows an optical micrograph showing the effects of corrosion testing on the exemplary Alloy 4 sample described above. Significant IGC attack due to the composition of Alloy 4 is clearly visible in the micrographs, where the ratio of Cu/[Zn/Mg/Si)] is in the range of about 0.7 to about 1.4, The Zn/(Mg/Si) ratio is not within the range of about 0.75 to about 1.4, resulting in significant IGC attack.

Figures 24A, 24B, and 24C are optical micrographs showing the results of corrosion tests on the above exemplary alloys. 24A shows intergranular corrosion (IGC) attack in Alloy A. FIG. 24B shows intergranular corrosion attack in Alloy B. FIG. 24C shows intergranular corrosion attack in alloy C. FIG. As is evident in Figures 24A, 24B, and 24C, the corrosion morphology changed from IGC to pitting with increasing Zn content, with a depth of corrosion attack from about 150 µm (Alloy A, Figure 24A) to less than 100 µm. (Alloy C, FIG. 24C).

All patents, publications, and abstracts cited above are hereby incorporated by reference in their entirety. Various embodiments of the invention have been described in fulfillment of the various objectives of the invention. It should be appreciated that these embodiments are merely illustrative of the principles of the invention. Many modifications and adaptations thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention as defined in the following claims.

Claims (26)

0.25-1.3 wt.% Si, 1.0-2.5 wt.% Mg, 0.5-1.5 wt.% Cu, 0.01-0.2 wt.% Fe, 0.01-0.2 wt. 01-3.0 wt% Zn, 0.01-0.15 wt% Zr, 0.01-0.5 wt% Mn, 0.01-0.15 wt% impurities, balance from Al become,
The Mg to Si ratio (Mg/Si ratio) by weight is 1.5 to 1 to 3.5 to 1,
The weight ratio of Zn to the Mg/Si ratio (Zn/(Mg/Si) ratio) is 0.75:1 to 1.4:1;
An aluminum alloy in which the individual elements of impurities are 0-0.05% by weight. Si is 0.55-1.1% by weight, Mg is 1.25-2.25% by weight, Cu is 0.6-1.0% by weight , and Fe is 0.05-0. 17% by weight , and 1.5-3.0% by weight of Zn . Si is 0.65-1.0% by weight, Mg is 1.5-2.25% by weight, Cu is 0.6-1.0% by weight , and Fe is 0.12-0. 17% by weight and 2.0 to 3.0% by weight of Zn . Aluminum alloy according to any one of the preceding claims, wherein Zr is present in an amount of 0.09-0.12% by weight. Aluminum alloy according to any one of the preceding claims, wherein Mn is present in an amount of 0.05-0.3% by weight. Aluminum alloy according to any one of the preceding claims, wherein the Mg/Si ratio by weight is between 2.0:1 and 3.0:1. 7. The aluminum alloy of claim 6 , wherein the Zn/(Mg/Si) ratio by weight is between 0.8:1 and 1.1:1. Claim 6 or wherein the ratio of Cu to said Zn/(Mg/Si) ratio by weight (Cu/[Zn/(Mg/Si)] ratio) is from 0.7:1 to 1.4:1 7. The aluminum alloy according to 7. 9. The aluminum alloy of claim 8 , wherein the Cu/[Zn/(Mg/Si)] ratio by weight is between 0.8:1 and 1.1:1. An aluminum alloy product comprising the aluminum alloy according to any one of claims 1-9 . 11. The aluminum alloy product of claim 10 , wherein the aluminum alloy product has a yield strength of at least 340 MPa at T6 temper. 12. The aluminum alloy product according to claim 11 , wherein the yield strength is 360 MPa to 380 MPa at T6 temper. The aluminum alloy product according to any one of claims 10 to 12, wherein said aluminum alloy product comprises an average intergranular corrosion pitting depth of less than 100 µm at T6 temper. 11. The aluminum alloy product of claim 10, wherein the aluminum alloy product comprises an r/t (bendability) ratio of 0.5 or less at T4 temper. The aluminum alloy product comprises one or _more precipitates selected from the group consisting of M _- phase precipitates ( _{MgZn2 and} /or Mg ₍ Zn,Cu) ₂ ) , Mg2Si, and _Al4Mg8Si7Cu2 The aluminum alloy product according to any one of claims 10 to 14 , comprising a product. 6. The aluminum alloy according to claim 15 , wherein said aluminum alloy product comprises M-phase precipitates ( _MgZn2 and/or Mg(Zn,Cu) ₂ ) in an average amount of at least 300,000,000 particles/ ^mm2 . product. 17. An aluminum alloy product according to claim 15 or 16 , wherein said aluminum alloy product _comprises Mg2Si in an average amount of at least 600,000,000 particles/mm< ² >. An aluminum alloy product according to any one of claims 15 to 17 , wherein said aluminum alloy product comprises Al ₄ Mg ₈ Si ₇ Cu ₂ in an average amount of at least 600,000,000 particles/mm ² . 19. Any of claims 15-18 , wherein the aluminum alloy product _comprises M _- phase precipitates ( _{MgZn2 and} /or Mg ₍ Zn,Cu) ₂ ) , Mg2Si , and _Al4Mg8Si7Cu2 . or the aluminum alloy product according to one item. The aluminum alloy product according to claim 19 , wherein the weight ratio of Mg ₂ Si to Al ₄ Mg ₈ Si ₇ Cu ₂ is from 1:1 to 1.5:1. 21. The method according to claim 19 or 20, wherein the ratio of Mg ₂ Si to M phase precipitates ( MgZn ₂ and/or Mg(Zn,Cu) ₂ ) by weight is between 1.5:1 and 3: 1 . aluminum alloy products. 19- wherein the ratio of Al ₄ Mg ₈ Si ₇ Cu ₂ to M-phase precipitates ( MgZn ₂ and/or Mg(Zn,Cu) ₂ ) by weight is from 1.5: 1 to 3:1 2 The aluminum alloy product according to any one of 1 . A method of manufacturing an aluminum alloy, comprising:
casting the aluminum alloy of claim 1 to form an aluminum alloy cast product;
homogenizing the aluminum alloy casting product;
hot rolling to provide a final gauge aluminum alloy;
solution heat treating said final gauge aluminum alloy. 24. The method of claim 23, further comprising preaging the final gauge aluminum alloy. 25. The method of claim 23 or 24 , wherein the aluminum alloy cast product is cast from a molten aluminum alloy containing scrap metal. 26. The method of claim 25 , wherein the scrap metal comprises 6xxx series aluminum alloys, 7xxx series aluminum alloys, or combinations thereof.

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