JP2024509070A - Variants of high-strength 5XXX aluminum alloys and their preparation method - Google Patents

Abstract

A novel 5XXX aluminum alloy that exhibits high strength and formability is described herein. The aluminum alloys described herein have higher Mg content than conventional 5xxx series aluminum alloys and exhibit high strength and formability. The aluminum alloys described herein are manufactured according to a method that involves continuous casting. [Selection diagram] None

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application refers to U.S. Provisional Patent Application No. 63/160,198, filed March 12, 2021, which is hereby incorporated by reference for all intents and purposes in its entirety. Claim interest and priority.

The present disclosure relates to the fields of metallurgy, aluminum alloys, aluminum fabrication, and related fields. In particular, the present disclosure provides novel 5XXX aluminum alloy variants with improved strength and formability and methods of making the same.

In order to respond to global environmental problems caused by exhaust gases, there is an increasing demand for supplying transportation vehicles with better fuel efficiency. In order to meet these demands, aluminum alloy materials are being used in place of conventionally used steel materials because aluminum alloys are lighter than steel. Generally, aluminum alloys used to manufacture automobile parts require higher strength and formability to meet the increasing demands of manufacturers.

Many aluminum manufacturers use 5xxx series aluminum alloys (ie, aluminum alloys containing magnesium as the main alloying component) for automotive parts. However, it is difficult to improve the ability of one property (such as strength) of 5xxx series aluminum without reducing the ability of another property (such as formability). Attempts to change the composition have not been successful. The main reason is that the mechanical properties (such as strength and formability) and processability of aluminum alloys are greatly affected by small changes in composition. For example, the composition of the AA5182 alloy includes a magnesium (Mg) content of 4.0% to 5.0% by weight, a manganese (Mn) content of 0.2% to 0.5% by weight, and a maximum iron ( Fe) content is 0.35% by weight, maximum silicon (Si) content is 0.2% by weight, maximum copper (Cu) content is 0.15% by weight, maximum chromium (Cr) content is The content is strictly controlled to be 0.1% by weight. When the Mg content of AA5182 is increased above 5% by weight to improve strength and/or formability, the aluminum alloy becomes significantly susceptible to cracking during the manufacturing process. Therefore, it is very difficult to produce 5xxx series aluminum alloys with higher strength and/or formability using conventional aluminum alloys or production methods.

The embodiments contained in this disclosure are defined by the claims, rather than this Summary. This Summary is a high-level overview of various aspects of the invention and introduces some 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 in determining the scope of the claimed subject matter. I haven't. The subject matter should be understood by reference to the entire specification, any or all drawings, and appropriate portions of each claim.

This specification describes an aluminum alloy that has higher strength and formability than conventional 5XXX aluminum alloys. In some embodiments, the present disclosure provides about 0-0.30 wt% Si, 0.01-0.40 wt% Fe, 0-1.0 wt% Cu, 0.01-0. 50 wt% Mn, 5.0-6.0 wt% Mg, 0-0.20 wt% Cr, 0-0.30 wt% Zn, 0-0.25 wt% Ti, max. 0 Regarding an aluminum alloy containing .15% by weight of impurities and Al. In some embodiments, the aluminum alloy includes 0.01-0.20 wt% Si, 0.01-0.30 wt% Fe, 0.01-0.90 wt% Cu, 0.01-0.20 wt% 0.40% by weight Mn, 5.1-6.0% by weight Mg, 0-0.10% by weight Cr, 0-0.20% by weight Zn, 0-0.10% by weight Ti, Contains impurities of up to 0.15% by weight, and Al. In some embodiments, the aluminum alloy includes 0.01-0.15 wt.% Si, 0.01-0.20 wt.% Fe, 0.05-0.80 wt.% Cu, 0.05-0.05 wt.% 0.30% by weight Mn, 5.2-6.0% by weight Mg, 0-0.05% by weight Cr, 0-0.10% by weight Zn, 0-0.05% by weight Ti, Contains impurities of up to 0.15% by weight, and Al. In some embodiments, the aluminum alloy includes 0.01-0.06 wt% Si, 0.02-0.15 wt% Fe, 0.20-0.80 wt% Cu, 0.05-0.06 wt% 0.20 wt% Mn, 5.3-6.0 wt% Mg, 0.001-0.02 wt% Cr, 0-0.05 wt% Zn, 0-0.03 wt% Contains Ti, impurities up to 0.15% by weight, and Al. In some embodiments, the aluminum alloy includes 0.01-0.05 wt% Si, 0.05-0.11 wt% Fe, 0.30-0.80 wt% Cu, 0.05-0.05 wt% 0.10 wt% Mn, 5.5-5.9 wt% Mg, 0.001-0.02 wt% Cr, 0-0.01 wt% Zn, 0.001-0.03 wt% % Ti, up to 0.15 wt. % impurities, and Al. In some embodiments, the aluminum alloy includes at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. . In some embodiments, the aluminum alloy includes a Fe-containing component having a grain size less than 5 microns. In some embodiments, the number density of Mg ₂ Si particles in the aluminum alloy microstructure is at least 500/mm ² . In some embodiments, the aluminum alloy has a yield strength of at least 130 MPa. In some embodiments, the aluminum alloy has an ultimate tensile strength of at least 300 MPa. In some embodiments, the aluminum alloy has a total elongation of at least 5%.

In some embodiments, the present disclosure provides a method of manufacturing an aluminum alloy product, the method comprising continuously casting an aluminum alloy to form a cast product, the aluminum alloy having a weight of 0 to 0.30 wt. % Si, 0.01-0.40 wt% Fe, 0-1.0 wt% Cu, 0.01-0.50 wt% Mn, 5.0-6.0 wt% Mg, Contains 0-0.20 wt% Cr, 0-0.30 wt% Zn, 0-0.25 wt% Ti, up to 0.15 wt% impurities, and Al, continuous casting, optional Optionally, the casting product may be flash homogenized, the casting product may be hot rolled to produce a hot rolled product, the hot rolled product may be coiled, the hot rolled product may be cooled. The present invention relates to a method that includes rolling to produce a cold rolled product and annealing the cold rolled product. In some embodiments, the aluminum alloy includes at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. . In some embodiments, continuous casting includes a solidification rate of at least 1° C./sec to produce the cast product. In some embodiments, annealing includes batch annealing or continuous annealing. In some embodiments, flash homogenization comprises heating the cast product at 400° C. to 600° C. for less than 10 minutes. In some embodiments, the method includes paint baking the cold rolled product after annealing to produce an aluminum alloy product. In some embodiments, the yield strength of the aluminum alloy product increases by 5 MPa or more after paint baking.

Further aspects, objects, and advantages will become apparent from a consideration of the detailed description.

1 illustrates a method of manufacturing an aluminum alloy according to some embodiments of the present disclosure. 1 shows a graph of the yield strength of a sample aluminum alloy measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. 2 shows a graph of the ultimate tensile strength of aluminum alloy samples measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. 2 shows a graph of the change in tensile properties of a sample aluminum alloy after paint baking simulation, measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. 2 shows a graph of the uniform elongation (Ag) of the aluminum alloy of the sample measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. Figure 3 shows a graph of the total elongation (A80) of the aluminum alloy of the sample, measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. A graph of the r value (r(10-15)) of the aluminum alloy of the sample measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. 2 shows a graph of average n values of sample aluminum alloys measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. A and B are longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction, respectively, with respect to the rolling direction in a process for manufacturing an aluminum alloy including batch annealing or continuous annealing, respectively. Figure 3 shows a graph of the average instantaneous n-values at different strain rates of the sample aluminum alloy measured at . Figure 2 shows the area percentage of Fe-containing components in the aluminum alloy microstructure of the sample aluminum alloy. The number density of Fe-containing components in the aluminum alloy microstructure of the sample aluminum alloy is shown. Figure 2 shows the area percentage of Mg ₂ Si component in the aluminum alloy microstructure of the sample aluminum alloy. The number density of Mg ₂ Si components in the aluminum alloy microstructure of the sample aluminum alloy is shown. A to E show photographs of the grain structure of sample aluminum alloys produced in a process involving batch annealing after cold rolling. A to E show photographs of the grain structure of sample aluminum alloys produced in a process involving continuous annealing after cold rolling.

Described herein are novel 5XXX aluminum alloy variants that exhibit high strength and formability, and methods of manufacturing the same. Surprisingly, the aluminum alloy described herein exhibits high strength and formability despite having a higher Mg content than conventional 5XXX aluminum alloys, and has the same properties as conventional 5XXX aluminum alloys. No processing problems (eg cracks during hot rolling). The aluminum alloys described herein have a continuous casting process described herein that allows for higher amounts of Mg (e.g., greater than 5% by weight) than other processes for producing 5XXX series aluminum alloys. can be manufactured using. By incorporating higher levels of Mg and utilizing continuous casting, the aluminum alloys described herein exhibit higher levels of strength and formability without the risk of cracking during the manufacturing process. The aluminum alloys and aluminum alloy manufacturing methods described herein provide superior properties compared to conventional 5XXX-based aluminum alloys.

Conventional AA5182 aluminum alloys for manufacturing automotive parts require tightly controlled compositions to meet minimum strength requirements while still maintaining formability to manufacture complex shapes. do. Aluminum alloys used in the manufacture of automobile parts generally require higher strength, and this means that such automobile parts are manufactured from Mg-rich aluminum alloys such as AA5182 aluminum alloy. I've been asking to be done. However, aluminum alloys with high Mg content are prone to cracking. Traditional approaches to reducing cracking mainly reduce grain size by providing more nucleation sites or by adding some alloying elements that can form additional grains that prevent the formation of the β phase. We will focus on the morphological change of the β phase (from continuous to discontinuous) in the field. However, as the amount of Mg increases, cracks worsen and the formability of the aluminum alloy decreases significantly.

The novel 5XXX aluminum alloy variants described herein have increased Mg content in the aluminum alloy composition, but avoid the cracking problems associated with high Mg aluminum alloys. In particular, the aluminum alloys described herein contain higher amounts of Mg and achieve higher strength and formability properties compared to the AA5182 aluminum alloy. As described herein, by increasing the content of Mg and incorporating other alloying elements (e.g., Mn, Cu, Si, etc.), the It can provide strength and formability. Specifically, as further described herein, the synergistic combination of alloying elements produces variants of 5XXX aluminum alloys that exhibit little or no cracking during the manufacturing process. Utilizing a continuous casting process increases the solidification rate of high Mg aluminum alloys and prevents cracking during the manufacturing process. Increasing the Mg content results in very high work hardening rates and dislocation accumulation, which can generate edge cracking during cold rolling, but this is due to the intermediate annealing step during cold rolling. control by running or managing a gentle pass schedule during cold rolling. The high Mg content aluminum alloys described herein have improved strength and formability and can replace many existing materials (steel, AA5182 alloy, etc.) in automotive applications.

DEFINITIONS AND DESCRIPTION As used herein, the terms "invention,""theinvention,""thisinvention," and "the present invention" broadly refer to the subject matter of this patent application and the following claims. intended to point. It is to be understood that statements containing these terms are not intended to limit the subject matter described herein or to limit the meaning or scope of the claims below.

This description refers to alloys identified by aluminum industry designations such as "series" or "5xxx." For an understanding of the numbering systems most commonly used to name and identify aluminum and its alloys, see International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and W, both published by the Aluminum Institute. rough aluminum Alloys” or “Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloy s in the Form of Castings and Ingot.

As used herein, the meanings of "a," "an," or "the" include singular and plural references unless the context clearly dictates otherwise.

As used herein, a plate generally has a thickness greater than about 15 mm. For example, plate refers 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. It's fine.

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 be 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 thick.

As used herein, sheet refers to an aluminum fabrication having a thickness of less than about 4 mm (e.g., less than 3 mm, less than 2 mm, less than 1 mm, less than 0.5 mm, less than 0.3 mm, or less than 0.1 mm). point to something For example, the sheet is about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, Approximately 1mm, approximately 1.1mm, approximately 1.2mm, approximately 1.3mm, approximately 1.4mm, approximately 1.5mm, approximately 1.6mm, approximately 1.7mm, approximately 1.8mm, approximately 1.9mm, approximately 2mm , about 2.1mm, about 2.2mm, about 2.3mm, about 2.4mm, about 2.5mm, about 2.6mm, about 2.7mm, about 2.8mm, about 2.9mm, about 3mm, about 3.1mm, about 3.2mm, about 3.3mm, about 3.4mm, about 3.5mm, about 3.6mm, about 3.7mm, about 3.8mm, about 3.9mm, or about 4mm thick can be.

As used herein, formability refers to the ability of a material to deform into a desired shape without fracturing, tearing, necking, oticing, or forming errors such as wrinkling, springback, or galling. refers to In engineering, formability can be classified by deformation mode. Examples of deformation modes include drawing, stretching, bending, and stretch flanging.

In this application, reference may be made to tempering or refining of alloys. For an understanding of the most commonly used alloy temper descriptions, see American National Standards (ANSI) H35 on Alloy and Temper Design Systems. Temper or temper F refers to the as-produced aluminum alloy. Thermal or temper O refers to the aluminum alloy after annealing. Temper or temper Hxx, also referred to herein as temper H, refers to a non-heat treated aluminum alloy after cold rolling, with or without heat treatment (eg, annealing). Suitable tempers H include tempers HX1, HX2, HX3, HX4, HX5, HX6, HX7, HX8, or HX9. Thermal or temper T1 refers to an aluminum alloy that has been cooled from hot working and naturally aged (eg, at room temperature). Thermal or temper T2 refers to an aluminum alloy that has been cooled from hot working, cold worked, and naturally aged. Thermal or temper T3 refers to an aluminum alloy solution that has been solution treated, cold worked, and naturally aged. Temper or temper T4 refers to an aluminum alloy solution that has been solution treated and naturally aged. Thermal or temper T5 refers to aluminum alloys that have been cooled from hot working and artificially aged (at high temperatures). Tempering or tempering T6 refers to an aluminum alloy solution that has been solution treated and artificially aged. T7 temper or temper refers to an aluminum alloy that has been solution treated and artificially overaged. T8x temper or temper refers to aluminum alloys that have been solution treated, cold worked, and artificially aged. T9 temper or temper refers to an aluminum alloy that has been solution treated, artificially aged, and cold worked. W tempering or tempering refers to an aluminum alloy after solution treatment.

As used herein, "room temperature" means a temperature of 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. , 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.

All ranges disclosed herein are to be understood to include the endpoints and any and all subranges subsumed therein. For example, the stated range "1 to 10" should be considered to include any and all subranges between and including the minimum value 1 and the maximum value 10, i.e., all subranges include 1 to 10. Starting from a minimum value of 1 to 6.1, for example, and ending with a maximum value of 10 or less, for example 5.5 to 10.

The following aluminum alloys are described in terms of elemental composition in weight percent (wt%) based on the total weight of the alloy. In the specific example of each alloy, the balance is aluminum and the maximum total weight percent of impurities is 0.15%.

Alloy Composition The properties of aluminum alloys are determined in part by the composition of the aluminum alloy. In certain aspects, the alloy can influence or even determine whether the alloy has suitable properties for a desired application.

The alloy described herein is a variant of the new 5xxx series aluminum alloy. This alloy exhibits high strength, high formability (eg, excellent elongation and formability properties), and resistance to cracking during the manufacturing process. The properties of the alloy can be achieved at least in part due to the elemental compositional properties of the alloy. In some examples, the novel 5XXX aluminum alloy variants described herein can include a higher Mg content than the Mg content of conventional 5XXX aluminum alloys, among other elements. One or more of Cu, Mn, and Si can be included in certain amounts, as described further below.

In some examples, the aluminum alloys described herein can have the following elemental compositions as shown in Table 1.

In some examples, the aluminum alloys described herein can have the following elemental compositions as shown in Table 2.

In some examples, the aluminum alloys described herein can have the following elemental compositions as shown in Table 3.

In some examples, the aluminum alloy may have the following elemental composition as presented in Table 4.

In some examples, the aluminum alloy may have the following elemental composition as presented in Table 5.

Silicon In some examples, the aluminum alloys described herein contain 0% to 0.30% (e.g., 0% to 0.25%, 0.01% to 0.5%, based on the total weight of the alloy). 20%, 0.01% to 0.15%, 0.01% to 0.10%, 0.01% to 0.06%, or 0.01% to 0.05%). . For example, the alloy may be 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0. 09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0. 19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0. 29%, or 0.30% Si. All are expressed as weight percentages.

Iron In some examples, the aluminum alloys described herein also have an iron content of 0.01% to 0.40% (e.g., 0.01% to 0.25%, 0.01% to 0.25%, 0.01% to 0.40%, based on the total weight of the alloy). 01% to 0.20%, 0.01% to 0.15%, 0.02% to 0.11%, or 0.05% to 0.11%). For example, the alloy may contain 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, Or it may contain 0.40% Fe. All are expressed as weight percentages. Aluminum alloys can contain up to 0.40% Fe, so they can be manufactured from higher amounts of recycled aluminum alloys.

Copper In some examples, the aluminum alloys described herein can contain up to 1.0% (e.g., 0% to 1.0%, 0.01% to 0.90%) based on the total weight of the alloy. , 0.05% to 0.80%, 0.20% to 0.80%, or 0.30% to 0.80%). For example, the alloy may contain 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.50%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.60%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.70%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.80%, 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.90%, 0.91%, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, Or it may contain 1.0% Cu. All are expressed as weight percentages. In some cases, aluminum compositions containing Cu in the amounts described herein improve paint bake response of aluminum alloys. For example, aluminum containing Cu in the amounts described herein exhibits improved strength and formability after paint bake when the aluminum alloy is subjected to continuous annealing. Furthermore, high Cu content increases the ultimate tensile strength and provides a higher work hardening range compared to alloys with lower Cu content. In some cases, adding more than 1.0% by weight of Cu to aluminum alloy compositions can lead to cracking during the casting or hot rolling process.

Manganese In some examples, the aluminum alloys described herein also contain manganese from 0.01% to 0.50% (e.g., from 0.01% to 0.40%, from 0.01% to 0.40%, based on the total weight of the alloy). 01% to 0.30%, 0.01% to 0.15%, 0.05% to 0.30%, 0.05% to 0.20%, 0.05% to 0.15%, or 0 .05% to 0.10%). For example, alloys include 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0 .10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0 .20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0 .30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0 .40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, or It can contain 0.50% Mn. All are expressed as weight percentages. In some embodiments, aluminum compositions containing Mn in amounts described herein provide excellent n-values (hardening index). In some cases, aluminum alloys with Mn content greater than 0.40 wt% reduce the n value due to solute resistance effects and also increase the volume fraction of constituent particles containing Fe and Si, resulting in Formability decreases. Therefore, the amount of Mn in the aluminum alloys described herein is finely controlled to prevent loss of formability.

Magnesium In some examples, the aluminum alloys described herein contain 5.0% to 6.0% (e.g., 5.1% to 6.0%, 5.2% to 6.0%, 5.3% to 6.0%, 5.4% to 6.0%, 5.5% to 6.0%, 5.5% to 5.9%, 5.6% to 5.9%, or 5.6% to 5.8%). In some examples, the alloy is 5.0%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%, 5.7%, 5 .8%, 5.9%, or 6.0% Mg. All are expressed as weight percentages. In some embodiments, including Mg in the aforementioned amounts in the alloys described herein functions as a solid solution strengthening element. As explained further below and as demonstrated in the Examples, aluminum alloys containing Mg contents in the amounts described herein surprisingly produce aluminum alloys with superior strength and formability. Manufacture. In some embodiments, aluminum compositions containing less than 5.0 weight percent Mg are unable to achieve high strength and/or formability. In some cases, aluminum compositions containing greater than 6.0 wt.% Mg (e.g., 6.5 wt.%) are very difficult to cold roll, requiring multiple intermediate annealing steps for rolling; This results in aluminum alloys that often develop a large amount of edge cracking during rolling.

Chromium In some examples, the aluminum alloys described herein can contain up to 0.20% (e.g., 0% to 0.20%, 0% to 0.10%, 0 % to 0.05%, 0.001% to 0.05%, 0.001% to 0.02%, 0.005% to 0.05%, or 0.01% to 0.05%) Contains Cr. For example, the alloy is 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, or 0.20% may contain Cr. In some embodiments, the addition of Cr in the amounts described above reduces pitting corrosion and increases strength through solid solution hardening. In some cases, Cr is absent (ie, 0%) in the alloy. All are expressed as weight percentages.

Zinc In some examples, the aluminum alloys described herein contain up to 0.30% (e.g., 0% to 0.25%, 0% to 0.20%, 0 %~0.10%, 0%~0.05%, 0.001%~0.05%, 0.001%~0.02%, 0.005%~0.05%, or 0.01% 0.05%). For example, the alloy is 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, or 0.30% Zn may be included. In some cases, Zn is not present in the alloy (ie, 0%). In some cases, excessive Zn addition (eg, greater than 0.30% by weight) worsens corrosion properties. Therefore, the amount of Zn in the aluminum alloys described herein is limited. All are expressed as weight percentages.

Titanium In some examples, the aluminum alloys described herein can contain up to 0.20% (e.g., 0%-0.20%, 0%-0.10%, 0% titanium), based on the total weight of the alloy. % to 0.05%, 0.001% to 0.05%, 0.001% to 0.02%, or 0.005% to 0.05%). . For example, the alloy is 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, or 0.20% may contain Ti. In some cases, Ti is absent (ie, 0%) in the alloy. All are expressed as weight percentages.

Trace Elements Optionally, the aluminum alloys described herein contain an amount of no more than 0.05%, no more than 0.04%, no more than 0.03%, no more than 0.02%, or no more than 0.01%. It may further contain other trace elements, which may be referred to as impurities. These impurities can include, but are not limited to, V, Ni, Hf, Zr, Sc, Sn, Ga, Ca, Bi, Na, Pb, or combinations thereof. Therefore, V, Ni, Hf, Zr, Sc, Sn, Ga, Ca, Bi, Na, or Pb is 0.05% or less, 0.04% or less, 0.03% or less, 0.02% or less, Alternatively, it may be present in the alloy in an amount of 0.01% or less. The sum of all impurities does not exceed 0.15% (eg 0.1%). In some examples, the aluminum alloy can include up to 0.15 wt. to improve corrosion resistance. All are expressed as weight percentages. The remaining percentage of each alloy may be aluminum.

Properties The aluminum alloys described herein exhibit excellent properties when produced according to the methods described herein. In some embodiments, the aluminum alloys described herein, when produced according to the continuous casting process described herein in combination with cold rolling followed by batch annealing, are similar to conventional 5XXX-based aluminum alloys. Comparison shows improved properties. In some embodiments, the aluminum alloys described herein, when produced according to the continuous casting process described herein in combination with continuous annealing after cold rolling, are similar to conventional 5XXX-based aluminum alloys. Comparison shows improved properties. This processing step significantly improves the strength and formability properties of the aluminum alloy.

In some examples, aluminum alloy products made from the aluminum alloys described herein can have a yield strength of about 130 MPa or greater. For example, an aluminum alloy product made from the aluminum alloy described herein may have a pressure of 130 MPa or more, 135 MPa or more, 140 MPa or more, 145 MPa or more, 150 MPa or more, 155 MPa or more, 160 MPa or more, 165 MPa or more, 170 MPa or more, 175 MPa or more, Or it may have a yield strength of 180 MPa or more. In some cases, the yield strength is about 130 MPa to about 250 MPa (eg, about 135 MPa to about 200 MPa, about 140 MPa to 190 MPa, or about 145 MPa to about 180 MPa), or anywhere therebetween. The aluminum alloy products described herein are measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. The yield strength can be shown as follows.

In some examples, aluminum alloy products made from the aluminum alloys described herein can have an ultimate tensile strength of about 300 MPa or greater. For example, an aluminum alloy product made from the aluminum alloy described herein may have a pressure of 300 MPa or more, 305 MPa or more, 310 MPa or more, 315 MPa or more, 320 MPa or more, 325 MPa or more, 330 MPa or more, 335 MPa or more, 340 MPa or more, 345 MPa or more, Or it may have a yield strength of 350 MPa or more. In some cases, the ultimate tensile strength is or anywhere between about 300 MPa to about 500 MPa (eg, about 305 MPa to about 450 MPa, about 310 MPa to about 400 MPa, or about 315 MPa to about 350 MPa). The aluminum alloy products described herein are measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. It can exhibit ultimate tensile strength such as

Aluminum alloy products made from the aluminum alloys described herein also exhibit increased yield strength after paint baking. For example, aluminum alloy articles made from the aluminum alloys described herein may yield at least 2 MPa, at least 4 MPa, at least 5 MPa, at least 10 MPa, at least 15 MPa, at least 20 MPa, or at least 25 MPa after a simulated paint bake cycle. Shows an increase in strength. In some embodiments, aluminum alloy products made from the aluminum alloys described herein are at a pressure of 2 MPa to 100 MPa, such as 5 MPa to 90 MPa, 10 MPa to 80 MPa, 20 MPa to 75 MPa, 25 MPa to 60 MPa, 30 MPa to 50 MPa. , or an increase in yield strength of 35 MPa to 45 MPa. The aluminum alloy products described herein are measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. improved yield strength. In some embodiments, the simulated paint bake cycle may include heating the aluminum alloy product to 185° C. for about 20 minutes.

The aluminum alloys described herein produced according to the methods described herein also exhibit high formability. High formability can be measured, for example, by measuring total elongation or uniform elongation. ISO/EN A80 is one suitable standard that can be used to test total elongation. ISO/EN Ag is one standard that can be used to test uniform elongation. In some examples, aluminum alloy products made from the aluminum alloys described herein can have an overall elongation (A80) of at least about 5% and up to about 30%. For example, aluminum alloy products made from the aluminum alloys described herein may be about 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% , 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%, or any total elongation in between. The aluminum alloy products described herein are measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. The total elongation can be shown as shown below.

In some examples, aluminum alloy products made from the aluminum alloys described herein can have a uniform elongation (Ag) of at least about 5% and up to about 30%. For example, aluminum alloy products made from the aluminum alloys described herein may be about 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14% , 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%, or any uniform elongation in between. The aluminum alloy products described herein are measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. It can exhibit uniform elongation as shown in the figure.

Another means of measuring formability is the r value (also known as Lankford's coefficient), which is the plastic strain ratio during tensile testing. The r-value is a measure of a sheet metal's deep drawability (i.e., the material's resistance to thinning or thickening when subjected to tension or compression). The r value can be measured according to ASTM E517 (2020). In some embodiments, aluminum alloy products made from the aluminum alloys described herein can be produced in any or all directions (longitudinal (L) direction, diagonal (D) direction, and/or transverse (T) direction). ) direction) of at least about 0.45, such as at least about 0.50, at least about 0.55, at least about 0.60, at least about 0.65, at least about 0.70, or at least about 0.75. may have a value. In some embodiments, aluminum alloy articles made from the aluminum alloys described herein have a particle diameter of 0.45 to 0.95, such as 0.50 to 0.95, in any or all directions. It may have an r value of 0.55-0.90, 0.60-0.90, 0.65-0.85, or 0.70-0.85.

The n value, or strain hardening index, gives an indication of how much harder or stronger a material becomes when plastically deformed. The n value can be measured according to ASTM E646 (2020). The r value measured over the 10%-20% strain range is denoted as n(10-20). For example, aluminum alloy products made from the aluminum alloys described herein may be at least about 0.10, such as at least about 0.15, at least about 0.20, at least about 0.25, or at least about 0. .30 in any individual direction or in all directions (longitudinal (L) direction, diagonal (D) direction, and/or transverse (T) direction). In some embodiments, aluminum alloy products made from the aluminum alloys described herein have a particle diameter of 0.10 to 0.50, such as 0.15 to 0.45, in any or all directions. , 0.20-0.40, 0.25-0.40, 0.30-0.40, or 0.30-0.35.

Microstructure of Aluminum Alloys The aluminum alloys described herein have a particle distribution that provides improved mechanical properties when produced according to the methods described herein. For example, the aluminum alloys described herein contain higher amounts of Mg (e.g., 5.0 wt.% to 6.0 wt.%) and/or Cu (e.g., 0.3 wt.%) than conventional 5xxx series aluminum alloys. ~1.0% by weight). Despite the higher amounts of Mg and/or Cu, the component formed by Fe was not significantly increased compared to the AA5182 alloy. As shown in FIGS. 10 and 11, the particle size distribution of the Fe component remains virtually the same. The area fraction of Al _x (Fe, Mn) and Al(Fe, Mn)Si particles in the aluminum alloy microstructure of aluminum alloys containing 5.0 wt% to 6.0% Mg was similar to that of AA5182 alloy. . Furthermore, the particle size of the Fe-containing constituent particles is small (eg, less than 5 microns) and is predominantly Al _x (Fe, Mn) particles in the aluminum alloy microstructure, which is similar to the AA5182 alloy. Therefore, the presence of higher amounts of Mg and Cu in the aluminum alloys described herein did not adversely affect the microstructure of the aluminum alloys.

In some embodiments, the aluminum alloys described herein are less than 10 microns, such as less than 9 microns, less than 8 microns, less than 7 microns, less than 6 microns, when produced according to the methods described herein. Fe-containing components having a particle size of less than 5 microns, less than 5 microns, or less than 4 microns. In some embodiments, the aluminum alloys described herein, when produced according to the methods described herein, have a particle diameter of 0.01 to 10 microns, such as 0.01 to 10 microns, 0.01 to 10 microns, Fe-containing components having particle sizes of 10 microns, 0.05-8 microns, 0.1-6 microns, 0.2-5 microns, or 0.2-4.5 microns.

The amount and size of Fe-containing constituent particles of the aluminum alloys described herein improve formability and corrosion resistance properties. Iron-containing constituent particles typically act as crack initiation sites and damage the aluminum alloy when subjected to deformation. Furthermore, when the constituent particles containing Fe are large, the corrosion potential becomes high and the corrosion performance decreases. Advantageously, the low amount and small size of Fe-containing constituent particles of the aluminum alloys described herein are favorable for both formability and corrosion resistance.

The aluminum alloys described herein exhibit increased Mg ₂ Si content compared to the AA5182 alloy when produced according to the methods described herein. Mg and Si combine as Mg ₂ Si and provide significant strength improvement after age hardening. 12 and 13 show graphs of Mg ₂ Si particle distribution for aluminum alloys, presenting the number density, area percent, and average size of Mg ₂ Si particles for example alloys. As shown in FIGS. 12 and 13, the particle size distribution of Mg ₂ Si particles in the aluminum alloy described herein was larger than in the AA5182 alloy. For example, FIG. 12 shows that the area percent Mg ₂ Si in the aluminum alloy was greater than 0.01% and the grain size was between 0.2 microns and 5 microns. The Mg ₂ Si number density and area fraction of the aluminum alloy described herein were greater than that of the AA5182 alloy.

In some embodiments, the aluminum alloys described herein are less than 10 microns, such as less than 9 microns, less than 8 microns, less than 7 microns, less than 6 microns, when produced according to the methods described herein. Mg ₂ Si particles having a particle size of less than 5 microns, or less than 4 microns. In some embodiments, the aluminum alloys described herein, when produced according to the methods described herein, have a particle diameter of 0.01 to 10 microns, such as 0.01 to 10 microns, 0.01 to 10 microns, Mg ₂ Si particles having a particle size of 10 microns, 0.05-8 microns, 0.1-6 microns, 0.2-5 microns, or 0.2-4.5 microns.

In some embodiments, when produced according to the methods described herein, the aluminum alloys described herein contain more than 0.013%, such as more than 0.013%, more than 0.015%, 0 Includes a peak area percentage of Mg ₂ Si particles that is greater than .018%, greater than 0.020%, greater than 0.021%, or greater than 0.025%. In some embodiments, when produced according to the methods described herein, the aluminum alloys described herein contain 0.013% to 0.030%, such as 0.014% to 0.028% %, 0.015% to 0.025%, 0.018% to 0.024%, or 0.020% to 0.024% of the peak area percentage of Mg ₂ Si particles.

In some embodiments, the aluminum alloys described herein, when produced according to the methods described herein, have an aluminum alloy of greater than 300/mm ² , such as greater than 325/mm ² , greater than 350/mm ² , 375 / ^mm2 , >400/ ^mm2 , >425/ ^mm2 , >450/ ^mm2 , _> 475/ ^mm2 , or >500/ ^mm2 . In some embodiments, when produced according to the methods described herein, the aluminum alloys described herein have a particle size of 300/mm ² to 600/mm ² , such as 325/mm ² to 575/mm ² , 350/mm ² to 550/mm ² , 375/mm ² to 525/mm ² , or 400/mm ² to 525/ _mm ² . In some embodiments, the total number density (overall number density) of Mg ₂ Si particles is less than 3000/mm ² .

The Mg ₂ Si particles are dissolved during high temperature annealing (eg, continuous annealing) for solid solution strengthening. The Mg ₂ Si particles form reinforcing precipitates during baking of the coating to further improve strength. The Fe-containing constituent particles and Mg ₂ Si particles function as a heterogeneous nucleation site during annealing, producing a fine grain orientation/random structure to improve formability.

Methods of Producing Aluminum Alloys In certain embodiments, the disclosed alloy compositions are products of the disclosed methods. Without intending to limit the disclosure, the properties of aluminum alloys are determined in part by the formation of microstructure during the preparation of the alloy. In certain embodiments, the method of preparing an alloy composition can influence or even determine whether the alloy has suitable properties for a desired application. In some embodiments, the aluminum alloys described herein can be manufactured by continuous casting, optional flash homogenization, hot rolling, coiling, cold rolling, and annealing.

In some embodiments, the method may include continuously casting the metal strip. The method of casting the metal strip can be any suitable continuous casting process. Surprisingly, however, the desired results were obtained using the continuous casting process described in U.S. Pat. This has been achieved using continuous casting processes such as. After casting, the method includes flash homogenizing the metal strip before hot rolling. The flash homogenization temperature and hot rolling duration are finely controlled to maintain the large grain size and high strength of the aluminum alloy. The metal strip is flash homogenized in a furnace at a temperature of 400°C to 500°C at a suitable heating rate, and then maintained at that temperature for a short period of time (e.g. up to 10 minutes) ("soaked" or "soaked"). be able to. After flash homogenization, the metal strip is hot rolled at a hot rolling temperature of 300° C. to 500° C. to produce a hot rolled product. Hot rolled products can be coil cooled. After coiling, the hot rolled product is cold rolled in a number of cold rolling passes to produce a cold rolled product. Cold rolled products can optionally be coiled. In some embodiments, the cold rolled product is batch annealed or continuously annealed to produce an aluminum alloy product.

FIG. 1 presents one exemplary system 100 for manufacturing the aluminum alloys described herein. In one example, system 100 can include a continuous caster 105, a furnace 110 (eg, a tunnel furnace), a hot rolling stand 115, a first coiler 120, a cold rolling stand 125, and a second coiler 130. In some cases, the system 100 includes a separated coil for casting, rolling, or otherwise fabricating a metal article (e.g., metal strip) suitable for providing a dispensable coil of metal strip. , or with partially separated continuous casting and rolling lines. As used herein, the term decoupled refers to removing the speed link between the casting equipment and the rolling stand(s). For example, continuous caster 105 may be separate from hot rolling stand 115. In some cases, hot rolling stand 115 can reduce the thickness of the metal strip by between 40% and 80%. In some cases, quenching before the hot rolling stand is optional, but grinding the Fe-containing particles and improving precipitation properties can be beneficial. In some cases, the metal strip cast from continuous caster 105 may be rolled (eg, hot rolled) before being coiled. In some cases, after the metal strip is hot rolled in multiple passes through hot rolling stand 115, the metal strip may be coiled in first coiler 120. The metal strip can be cooled before being coiled in the first coiler 120 or simultaneously as it is wound. The metal strip can be uncoiled and cold rolled on cold rolling stand 125. In some cases, cold rolling stand 125 can reduce the thickness of the metal strip by more than 50%. After cold rolling, the metal strip is optionally coiled and then batch or continuous annealed.

Casting The alloys described herein can be cast into metal articles (eg, metal strip) using a continuous casting (CC) process. Continuous casting involves continuously injecting molten metal into a casting cavity defined between a pair of moving, opposing casting surfaces and withdrawing a cast metal mold (e.g., metal strip) from an outlet of the casting cavity. Surprisingly, beneficial results can be achieved by intentionally separating the casting process from the hot rolling process in continuous casting and rolling systems. By separating the continuous casting process from the hot rolling process, there is no longer a need to closely match casting and rolling speeds. Rather, the casting speed can be selected to produce the desired properties in the metal strip, and the rolling speed can be selected based on the requirements and limitations of the rolling equipment. In a separate continuous casting and rolling system, the continuous casting equipment can cast a metal strip that is immediately or shortly thereafter coiled into an intermediate or transfer coil. The intermediate coil can be stored or taken immediately to the rolling mill. In the rolling mill, the intermediate coil can be unwound and the metal strip passes through the rolling mill to undergo processing, such as hot rolling. The end result of the hot rolling process is a metal strip that can have properties desirable for a particular customer. In some cases, the metal strip can also be coiled and shipped, such as to an automotive factory, where automotive parts can be formed from the metal strip. In some cases, the metal strip may be heated at various times after it is initially cast in a continuous casting process (e.g., by a continuous caster), but the metal strip may be heated to the solidus temperature of the metal strip. remains unreached.

The casting equipment may be any suitable continuous casting equipment. Surprisingly, however, the desired results have been achieved using belt casting equipment such as the belt casting equipment described in U.S. Pat. , the disclosure of which is incorporated herein by reference in its entirety. In some cases, particularly desirable results can be achieved by using belt casting equipment with belts made from metals with high thermal conductivity, such as copper. Belt casting equipment may include a belt made from a metal having a thermal conductivity of at least 250, 300, 325, 350, 375, or 400 watts/meter/Kelvin at the casting temperature, but with other values of thermal conductivity. Metals with conductivity can also be used. Although the casting equipment is capable of casting metal strip to any suitable thickness, desirable results have been achieved with thicknesses of about 5 mm to 50 mm.

In some cases, the casting equipment is capable of rapidly solidifying the metal strip (e.g., rapidly solidifying at a rate of about 10 times or more than standard DC casting solidification, at least or about 1°C/sec, at least or about 10°C). /second, or at least or about 100°C/second), and rapid cooling (e.g., rapid cooling at a rate of at least or about 1°C/second, at least or about 10°C/second, or at least or about 100°C/second). It can be configured to bring about an improvement in the microstructure of the final metal strip. In some cases, the solidification rate can be more than 100 times that of conventional DC casting. The rapid solidification results in a unique microstructure, including a unique distribution of dispersoid-forming elements that are very uniformly distributed throughout the solidified aluminum matrix. Rapid cooling of the metal strip, such as quenching the metal strip as it exits the casting apparatus or immediately thereafter, facilitates fixing the dispersoid-forming elements in solid solution. The resulting metal strip can then be supersaturated with dispersoid-forming elements. The supersaturated metal strip can then be coiled into intermediate coils for further processing in a separate casting and rolling system. In some cases, the desired dispersoid-forming elements include Mn, Cr, V, and/or Zr. This metal strip, supersaturated with dispersoid-forming elements, can very quickly induce the precipitation of uniformly distributed dispersoids of the desired size upon reheating.

In some cases, rapid solidification and rapid cooling can also be performed independently by the casting apparatus. The casting apparatus can be of sufficient length and have sufficient heat removal properties to produce a metal strip supersaturated with dispersoid-forming elements. In some cases, the casting equipment is of sufficient length and has sufficient heat removal properties to reduce the temperature of the cast metal strip to below 250°C, 240°C, 230°C, 220°C, 210°C, or 200°C. However, other values can also be used. Generally, such casting equipment occupies considerable space or must operate at slow casting speeds. In some cases, if a smaller, faster casting device is desired, the metal strip can be quenched immediately after exiting the casting device, or shortly thereafter. One or more nozzles are placed downstream of the casting equipment to increase the temperature of the metal strip to 250°C, 240°C, 230°C, 220°C, 210°C, 200°C, 175°C, 150°C, 125°C, or 100°C However, other values can also be used. The quenching can occur quickly or quickly enough to lock the dispersoid-forming elements in the supersaturated metal strip.

The metal strip can then be subjected to further processing steps. Optionally, further processing steps may be used to prepare the sheet. Such processing steps include, but are not limited to, optional flash homogenization steps, hot rolling steps, cold rolling steps, and annealing steps. The processing steps are described below in connection with the metal strip. However, the processing steps can also be used for cast slabs or strips using modifications known to those skilled in the art.

Homogenization Optionally, when a homogenization step is performed, the metal strip prepared from the alloy composition described herein is heated to a homogenization temperature, such as a temperature in the range of about 400°C to 600°C. obtain. For example, the metal strip may be approximately 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. ℃, or can be heated to a temperature of 550℃. In some cases, the metal strip can be flash homogenized. Flash homogenization involves subjecting the metal strip to a temperature above 500°C (e.g., 500°C to 570°C, 520°C to 560°C, or about 560°C) for a relatively short period of time (e.g., about 1 minute to 10 minutes, For example, 30 seconds, 45 seconds, 1 minute, 1.5 minutes, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, or any range in between) Heating may be included. This heating occurs between the continuous caster and any initial coiling, more specifically between the continuous caster and the hot rolling stand prior to coiling, or between that hot rolling stand and coiling. It can happen. This flash homogenization can help reduce the aspect ratio of Fe-containing particles and can also reduce the size of these particles. In some cases, flash homogenization (e.g., about 2 minutes at 570°C) may result in beneficial spheroidization and/or purification of Fe-containing particles that would otherwise require extensive homogenization at elevated temperatures. can be successfully achieved.

In some cases, an optional soaking furnace (eg, a tunnel furnace) can be placed downstream of the continuous belt caster near the outlet of the continuous belt caster to provide flash homogenization. Using a soaking oven can facilitate achieving a uniform temperature profile across the width of the metal strip. Additionally, the soaking furnace can flash homogenize the metal strip, which can prepare the metal strip to improve the fracture of iron-containing particles during hot rolling.

Hot Rolling The metal strip, or optionally homogenized metal strip if a homogenization step is performed, can be subjected to a hot rolling step to produce a hot rolled product. In some cases, metal strip cast from a continuous caster can be rolled (e.g., hot rolled) before being coiled. Rolling before coiling can significantly reduce the thickness, eg, by at least 30% or more, more typically between 50% and 75%. Particularly useful results have been found when continuously cast metal strip is rolled in a single hot rolling stand prior to coiling, although additional stands may be used in some cases. In some cases, this high reduction after continuous casting (e.g., greater than 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or 75% of the thickness) Hot rolling (reduction) can serve to crush Fe-containing particles in the metal strip, among other benefits. In some embodiments, the hot rolling is from about 300°C to about 500°C (e.g., about 300°C, about 310°C, about 320°C, about 330°C, about 340°C, about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, about 400°C, about 410°C, about 420°C, about 430°C, about 440°C, or about 450°C, about 460°C, about 470°C, about 480°C, about 490°C, or about 500°C).

In some cases, the combination of continuous casting followed by flash homogenization and hot rolling described herein may be particularly useful for refining (eg, milling) Fe-containing particles. Hot rolled products can be cold coiled after hot rolling. Hot rolled products can be cold coiled at temperatures ranging from about 200°C to 400°C. In some embodiments, the hot rolled product is coil cooled to facilitate cold rolling and to modify the grain and crystal structure of the aluminum alloy. For example, hot rolled products may be heated to about 200°C (e.g., about 210°C, about 220°C, about 230°C, about 240°C, about 250°C, about 260°C, about 270°C, about 280°C, about 290°C). , about 300°C, about 310°C, about 320°C, about 330°C, about 340°C, about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, or about 400°C). can be converted into

Cold Rolling One or more cold rolling steps can then optionally be performed to obtain a cold rolled product. Hot rolled products can be uncoiled using an uncoiler. The hot rolled product uncoiled can be cold rolled on a cold rolling stand. Hot rolled products can be cold rolled using a cold rolling mill into thinner products such as cold rolled sheets. Cold rolling is more than 50% (e.g., more than 55%, more than 60%, more than 65%, more than 70%, more than 75%, more than 80%, 85%) compared to the gauge before the start of cold rolling. This can be done to yield a final gauge thickness representing a gauge reduction of greater than, or greater than 90% reduction. In some embodiments, the cold rolling step may include one or more cold rolling steps to achieve the desired gauge thickness reduction. Optionally, the process for producing aluminum alloys can include an interannealing step (eg, between one or more cold rolling steps). In some cases, cold rolled products may be coiled after cold rolling.

Annealing Cold rolled products can be annealed after cold rolling. The annealing process can be performed as a batch annealing or a continuous annealing.

In some embodiments, batch annealing can be performed after cold rolling. In some cases, the batch annealing step is from about 300°C to about 450°C (e.g., about 310°C, about 320°C, about 330°C, about 340°C, about 350°C, about 360°C, about 370°C, about 380°C, about 390°C, about 400°C, about 410°C, about 420°C, about 430°C, about 440°C, or about 450°C). In some cases, the heating rate in the batch annealing step is from about 10°C/hour to about 100°C/hour (e.g., from about 20°C/hour to about 90°C/hour, from about 30°C/hour to about 85°C/hour). time, about 40°C/hour to about 80°C/hour, about 50°C/hour to about 75°C/hour, about 30°C/hour to about 80°C/hour, about 40°C/hour to about 70°C/hour, or about 50° C./hour to about 60° C./hour). In some cases, the cold rolled product is heated for up to about 5 hours (e.g., about 30 minutes to about 4 hours, about 45 minutes to about 3 hours, or about 1 hour to about 2 hours) during the batch annealing step. until) immersed. For example, the cold rolled product may be heated at a temperature of about 300° C. to about 450° C. for about 20 minutes, about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, about 2 hours, about 3 hours, Soaking can be for about 4 hours, about 5 hours, or any time in between. In one example, the cold rolled product is heated to a temperature of about 350°C to about 400°C at a heating rate of about 50°C/hour to about 75°C/hour, soaked for about 1 hour to about 2 hours, and Cool at a cooling rate of from 0.degree. C./hour to about 30.degree. C./hour.

In some embodiments, continuous annealing can be performed after cold rolling. In some cases, the sequential annealing steps range from about 400°C to about 600°C (e.g., about 410°C, about 420°C, about 430°C, about 440°C, about 450°C, about 460°C, about 470°C, about 480°C). °C, about 490 °C, about 500 °C, about 510 °C, about 520 °C, about 530 °C, about 540 °C, about 550 °C, about 560 °C, about 570 °C, about 580 °C, about 590 °C, or about 600 °C ) at the peak metal temperature. In some cases, the heating rate in the continuous annealing step is about 0.1°C/sec to about 30°C/sec (e.g., about 0.2°C/sec to about 28°C/sec, about 0.3°C/sec). seconds to about 28°C/second, about 0.4°C/second to about 25°C/second, about 0.5°C/second to about 20°C/second, about 0.8°C/second to about 18°C/second, from about 1° C./second to about 15° C./second, or from about 2° C./second to about 10° C./second). In some cases, the cold rolled product is soaked for up to about 1 minute (eg, 0 seconds, 5 seconds, 10 seconds, or 30 seconds) between successive annealing steps. In one example, the cold rolled product is heated to a temperature of about 400° C. to about 600° C. at a heating rate of about 0.5° C./second to about 20° C./second and soaked for about 0 seconds to about 5 seconds; Cooling is performed at a cooling rate of about 5° C./second to about 200° C./second.

Methods of Using the Disclosed Aluminum Alloy Products The aluminum alloy products described herein can be used in automotive applications and other transportation applications, including aircraft, rail applications. For example, the disclosed aluminum alloy products can be used to produce bumpers, side beams, roof beams, cross beams, pillar reinforcements (e.g., A-pillars, B-pillars, and C-pillars), inner panels, outer panels (skin ), side panels, inner hoods, outer hoods, or trunk lid panels. The aluminum alloy products and methods described herein can also be used to make exterior and interior panels in aircraft or rail vehicle applications, for example.

The aluminum alloy products and methods described herein can also be used in electronics applications. For example, the aluminum alloy products and methods described herein can be used to make housings for electronic devices, including cell phones and tablet computers. In some examples, aluminum alloy products can be used to make housings for the outer casing of mobile phones (e.g., smartphones), the bottom chassis of tablets, and other portable electronic devices.

Example 1: Mechanical Properties Alloys 1-3 are exemplary alloys made according to the method described below. Alloy A is a conventional AA5182 aluminum alloy currently used in automotive body parts.

Alloys 1-3 shown in Table 6 were continuously cast into metal strips based on the method described herein. The metal strip was flash homogenized in a tunnel furnace operating at a temperature of 400°C to 500°C. The metal strip was hot rolled in a hot rolling stand to obtain a hot rolled product with a gauge thickness reduction of 40% to 80%. The hot rolled product was coil cooled to a temperature of approximately 350°C. The hot rolled product was uncoiled and cold rolled in a cold rolling stand to yield a cold rolled product with a gauge thickness reduction of greater than 50%. The cold rolled product was coiled. The cold rolled products were subjected to batch annealing or continuous annealing to produce the final aluminum alloy products. Alloy A was direct cool cast or continuous cast.

Strength (mM)
Strength properties of exemplary and comparative alloys were measured. Specifically, the alloy was tested for yield strength and ultimate tensile strength.

FIG. 2 shows the results of yield strength tests for Alloys 1 to 3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. The yield strength values for Alloy A produced using direct cooling casting and continuous casting are shown in the first two columns. The yield strength values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing the yield strength in the L, T, and D directions, the bar on the left shows the yield strength after continuous annealing, and the bar on the right shows the yield strength after batch annealing. Compared with continuous annealing, the yield strength of the aluminum alloy obtained after batch annealing was slightly higher. The continuously cast Alloy A examples showed an increase in yield strength of about 15 MPa to 20 MPa compared to the direct cool cast examples. Alloys 1-3 exhibited higher yield strengths in the L, T, and D directions compared to both examples of Alloy A. The higher Mg content of Alloys 1-3, in combination with the production of aluminum by the continuous casting process described herein, is due to the higher amount of solute retained in solution in aluminum alloys produced by direct cooling casting. yielded higher strength compared to Furthermore, alloys 1-3 showed higher strength values with increasing amounts of Mg and Cu.

Figure 3 shows the ultimate tensile strength test results of Alloys 1 to 3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. show. The ultimate tensile strength values for Alloy A produced using direct cooling casting and continuous casting are shown in the first two columns. The ultimate tensile strength values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing the ultimate tensile strength in the L, T, and D directions, the bar on the left shows the ultimate tensile strength after continuous annealing, and the bar on the right shows the ultimate tensile strength after batch annealing. Compared with continuous annealing, the ultimate tensile strength of the aluminum alloy obtained after batch annealing was slightly higher. Alloys 1-3 exhibited higher ultimate tensile strengths in the L, T, and D directions compared to both examples of Alloy A. Alloys 1-3 produced according to the continuous casting process described herein resulted in higher tensile strength compared to direct cooling casting and conventional continuous casting.

Alloys 1-3 and Alloy A were tested to determine the effect of paint baking on the tensile properties of aluminum alloys. Figure 4 shows the tensile strengths of Alloys 1 to 3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction after the paint baking simulation. The results of the test are shown below. In the paint bake simulation, each alloy was heated to 185° C. and maintained at this temperature for approximately 20 minutes. The changes in tensile strength values for Alloy A produced using direct cooling casting and continuous casting are shown in the first two columns. The changes in the tensile strength values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for Alloys 1-3 and Alloy A, respectively. For each bar representing the change in tensile strength values in the L, T, and D directions, the bar on the left shows the change in tensile strength value after continuous annealing, and the bar on the right shows the change in tensile strength value after batch annealing. shows. Alloy A did not show any increase in strength after the paint bake cycle, regardless of the manufacturing method. Alloys 1-3 showed higher strength increases as the Cu content of the alloys increased. For example, Alloy 3 containing 0.8% by weight of Cu showed the largest increase in tensile strength after the paint baking simulation. Furthermore, the variants manufactured using the continuous annealing process showed a better response to paint baking due to the higher annealing temperature.

Formability Formability characteristics of exemplary and comparative alloys were determined. Specifically, the alloys were tested for uniform elongation, total elongation, r-value, and n-value to determine the formability of the exemplary and comparative alloys.

Figure 5 shows the results of uniform elongation tests for Alloys 1 to 3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. . The uniform elongation values for alloy A produced according to the direct cooling casting method and the continuous casting method are shown in the first two columns. The uniform elongation values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing uniform elongation in the L, T, and D directions, the bar on the left indicates uniform elongation after continuous annealing, and the bar on the right indicates uniform elongation after batch annealing. Uniform elongation was higher for aluminum alloys obtained after continuous annealing compared to batch annealing. Alloys 1-3 exhibited higher uniform elongation in the L, T, and D directions compared to both examples of Alloy A. Alloys 1-3 had higher uniform elongation as the amount of Mg increased.

Figure 6 shows the results of tests for total elongation of Alloys 1-3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction relative to the rolling direction, respectively. . The total elongation values for Alloy A produced according to the direct cooling casting method and the continuous casting method are shown in the first two columns. The total elongation values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing uniform elongation in the L, T, and D directions, the bar on the left shows the total elongation after continuous annealing, and the bar on the right shows the total elongation after batch annealing. The total elongation was higher for the aluminum alloys obtained after continuous annealing compared to batch annealing. Alloys 1-3 exhibited higher total elongation in the L, T, and D directions compared to both examples of Alloy A. Alloys 1-3 had higher total elongation as the amount of Mg increased.

FIG. 7 shows the r values of Alloys 1-3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. The r values of alloy A produced according to the direct cooling casting method and the continuous casting method are shown in the first two columns. The r-values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing the r-value in the L, T, and D directions, the bar on the left shows the r-value after continuous annealing, and the bar on the right shows the r-value after batch annealing. Compared with continuous annealing, the r value of the aluminum alloy obtained after batch annealing was slightly higher. Alloys 1-3 exhibited lower r values in the L, T, and D directions compared to Alloy A.

FIG. 8 shows the n values of Alloys 1 to 3 and Alloy A measured in the longitudinal (L) direction, transverse (T) direction, and/or diagonal (D) direction with respect to the rolling direction, respectively. The n values for alloy A produced according to the direct cooling casting method and the continuous casting method are shown in the first two columns. The n-values of the alloys after batch annealing (BA) and continuous annealing (CAL) are presented for each of Alloys 1-3 and Alloy A. For each pair of bars representing n values in the L, T, and D directions, the bar on the left shows the n value after continuous annealing, and the bar on the right shows the n value after batch annealing. The n values were similar for the aluminum alloys obtained after batch annealing and continuous annealing. Alloys 1-3 exhibited higher n values in the L, T, and D directions compared to both examples of Alloy A. Alloys 1-3 showed an approximately 10% increase in n value compared to Alloy A. The increase in Mg content of alloys 1-3 contributed to the increase in n value.

9A and 9B show the instantaneous n values for Alloys 1-3 and Alloy A over a range of strain rates after batch and continuous annealing, respectively. Alloys 1-3 showed higher retention of n values at higher strain rates compared to Alloy A. Surprisingly, aluminum alloys with higher Mg content in alloys 1-3 exhibited significantly lower rates of n-value decay as the strain rate increased. In the batch annealed samples of Alloys 1 to 3, a decrease in the n value was observed after reaching a strain of 7%, whereas in the continuously annealed samples, almost no decrease in the n value was observed. High n values at high strain rates result in better forming windows for alloys 1-3.

Example 2: Microstructure Aluminum alloys produced according to the methods described herein exhibited a microstructure with the properties described herein. 10 and 11 show the particle distribution of Fe-containing components in the aluminum alloy microstructures of Alloy 2 (dashed line) and Alloy A (solid line). The Fe component particle distribution of Alloy 2 with an Mg content of 5.8% by weight was similar to the Fe component particle distribution of Alloy A. FIG. 10 shows that the area fraction of Al _x (Fe, Mn) in Alloy 2 was substantially the same as Alloy A. Alloy 2 and Alloy A both had an area fraction of Al _x (Fe, Mn) of less than 0.06%. Similarly, the area fraction of Al(Fe,Mn)Si was substantially the same in Alloy 2 and Alloy A. Figure 11 shows that the number densities of Al _x (Fe, Mn) and Al (Fe, Mn) Si particles in the aluminum alloy microstructure were also similar for Alloy 2 and Alloy A. Alloy 2 and Alloy A both had Fe component particles with a particle size of less than 5 microns with an aluminum alloy microstructure consisting primarily of Al _x (Fe, Mn) particles. Although Alloy 2 had high concentrations of Mg and Cu, the alloy composition did not substantially change the particle distribution of the Fe component.

12 and 13 show graphs of Mg ₂ Si particle distribution in the aluminum alloy microstructures of Alloy 2 (dashed line) and Alloy A (solid line). Figure 12 shows the area % of _Mg2Si particles in the aluminum alloy microstructure, and Figure 13 shows the number of _Mg2Si particles in the aluminum alloy microstructure. Alloy 2 exhibited higher area fraction and number density of Mg ₂ Si particles compared to Alloy A. Specifically, Alloy A has an area % of Mg ₂ Si particles of 0.129 and a number density of Mg ₂ Si particles of 1186.33/mm ² , whereas Alloy 2 has an area % of Mg 2 Si particles of 0.212/mm 2 . It had an area % of ₂ Si particles and a number density of Mg ₂ Si particles of 2125.31/mm ² . Mg and Si combine as Mg ₂ Si and provide significant strength improvement after age hardening. Therefore, Alloy 2 showed significant advantages in strength compared to Alloy A. As discussed herein, the carefully balanced composition of aluminum alloys plays an important role in controlling the strength and formability of aluminum alloys. Furthermore, Alloy A utilizing direct cooling casting has a lower cooling rate (e.g. 4°C/s to 6°C/s) compared to continuous casting (e.g. 100°C/s to 200°C/s). As a result, coarse intermetallic particles are produced in both Fe-containing components and Mg ₂ Si particles. Therefore, direct cooling casting is difficult for high solute alloys due to the longer solidification range, resulting in hot cracking.

14A-E show photographs of the grain structure of Alloy A and Alloys 1-3 after batch annealing, and FIGS. 15A-E show photographs of the grain structure of Alloy A and Alloys 1-3 after continuous annealing. Alloys 1-3 produced using batch annealing had elongated grains, while alloys 1-3 produced using continuous annealing exhibited equiaxed grains. When Mg was added to the aluminum alloy compositions of Alloys 1 to 3, the particles were slightly refined compared to Alloy A.

Examples of preferred methods and alloy products Example 1 includes 0-0.30 wt% Si, 0.01-0.40 wt% Fe, 0-1.0 wt% Cu, 0.01-0 .50 wt% Mn, 5.0-6.0 wt% Mg, 0-0.20 wt% Cr, 0-0.30 wt% Zn, 0-0.25 wt% Ti, max. It is an aluminum alloy containing 0.15% by weight of impurities and Al.

In Example 2, the aluminum alloy contains 0.01-0.20% by weight of Si, 0.01-0.30% by weight of Fe, 0.01-0.90% by weight of Cu, 0.01-0. .40 wt% Mn, 5.1-6.0 wt% Mg, 0-0.10 wt% Cr, 0-0.20 wt% Zn, 0-0.20 wt% Ti, max. The aluminum alloy of any preceding or subsequent example containing 0.15% by weight of impurities and Al.

In Example 3, the aluminum alloy contains 0.01-0.15% by weight of Si, 0.01-0.20% by weight of Fe, 0.05-0.80% by weight of Cu, and 0.05-0. .30 wt% Mn, 5.2-6.0 wt% Mg, 0-0.05 wt% Cr, 0-0.10 wt% Zn, 0-0.10 wt% Ti, max. The aluminum alloy of any preceding or subsequent example containing 0.15% by weight of impurities and Al.

In Example 4, the aluminum alloy contains 0.01-0.06% by weight of Si, 0.02-0.15% by weight of Fe, 0.20-0.80% by weight of Cu, and 0.05-0. .20 wt% Mn, 5.3-6.0 wt% Mg, 0.001-0.02 wt% Cr, 0-0.05 wt% Zn, 0-0.03 wt% Ti , up to 0.15% by weight of impurities, and Al.

In Example 5, the aluminum alloy contains 0.01-0.05% by weight of Si, 0.05-0.11% by weight of Fe, 0.30-0.80% by weight of Cu, and 0.05-0. .10 wt% Mn, 5.5-5.9 wt% Mg, 0.001-0.02 wt% Cr, 0-0.01 wt% Zn, 0.001-0.03 wt% of Ti, up to 0.15% by weight of impurities, and Al of any preceding or subsequent example.

Example 6 provides that the aluminum alloy comprises at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. Any preceding or subsequent instance of an aluminum alloy.

Example 7 is the aluminum alloy of any preceding or subsequent example in which the grain size of the Fe-containing component is less than 5 microns.

Example 8 is the aluminum alloy of any preceding or subsequent example, wherein the number density of Mg ₂ Si particles in the aluminum alloy microstructure is at least 500/mm ² .

Example 9 is the aluminum alloy of any preceding or subsequent example, wherein the aluminum alloy has a yield strength of at least 130 MPa.

Example 10 is the aluminum alloy of any preceding or subsequent example, wherein the aluminum alloy has an ultimate tensile strength of at least 300 MPa.

Example 11 is the aluminum alloy of any preceding or subsequent example, wherein the aluminum alloy has a total elongation of at least 5%.

Example 12 is an aluminum alloy product that includes the aluminum alloy of any of the preceding or subsequent examples.

Example 13 is the aluminum alloy product of any preceding or subsequent example, where the aluminum alloy product is produced by continuous casting, flash homogenization, hot rolling, and cold rolling.

Example 14 is a method for manufacturing an aluminum alloy product, in which the aluminum alloy is continuously cast to form a cast product, the aluminum alloy containing 0 to 0.30% by weight of Si, 0.01% by weight. ~0.40 wt% Fe, 0-1.0 wt% Cu, 0.01-0.50 wt% Mn, 5.0-6.0 wt% Mg, 0-0.20 wt% Cr, 0-0.30 wt.% Zn, 0-0.25 wt.% Ti, up to 0.15 wt.% impurities, and Al. flash homogenizing the cast product, hot rolling the cast product to produce a hot rolled product, coiling the hot rolled product, cold rolling the hot rolled product. producing a cold rolled product; and annealing the cold rolled product.

Example 15 includes at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. The method of any preceding or subsequent instance.

Example 16 is the method of any preceding or subsequent example, wherein continuous casting includes a solidification rate of at least 1° C./sec to produce the cast product.

Example 17 is a method of any preceding or subsequent example, where the annealing comprises batch annealing or continuous annealing.

Example 18 is the method of any preceding or subsequent example, wherein flash homogenization comprises heating the cast product at 400° C. to 600° C. for less than 10 minutes.

Example 19 is the method of any preceding or subsequent example further comprising paint baking the cold rolled product after annealing to produce an aluminum alloy product.

Example 20 is the method of any preceding or subsequent example in which the yield strength of the aluminum alloy product increases by 5 MPa or more after paint baking.

All patents, publications, and abstracts cited above are incorporated herein by reference in their entirety. Various embodiments of the invention have been described to accomplish various objectives of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the invention. Numerous changes and modifications 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 (20)

0-0.30 wt% Si, 0.01-0.40 wt% Fe, 0-1.0 wt% Cu, 0.01-0.50 wt% Mn, 5.0-6. Aluminum with 0 wt% Mg, 0-0.20 wt% Cr, 0-0.30 wt% Zn, 0-0.25 wt% Ti, up to 0.15 wt% impurities, and Al alloy. The aluminum alloy contains 0.01-0.20% by weight of Si, 0.01-0.30% by weight of Fe, 0.01-0.90% by weight of Cu, and 0.01-0.40% by weight. of Mn, 5.1-6.0 wt% Mg, 0-0.10 wt% Cr, 0-0.20 wt% Zn, 0-0.10 wt% Ti, up to 0.15 wt% % impurities, and Al as claimed in claim 1. The aluminum alloy contains 0.01-0.15% by weight of Si, 0.01-0.20% by weight of Fe, 0.05-0.80% by weight of Cu, and 0.05-0.30% by weight. of Mn, 5.2-6.0 wt% Mg, 0-0.05 wt% Cr, 0-0.10 wt% Zn, 0-0.05 wt% Ti, up to 0.15 wt% % impurities, and Al as claimed in claim 1. The aluminum alloy contains 0.01-0.06% by weight of Si, 0.02-0.15% by weight of Fe, 0.20-0.80% by weight of Cu, and 0.05-0.20% by weight. of Mn, 5.3-6.0 wt% Mg, 0.001-0.02 wt% Cr, 0-0.05 wt% Zn, 0-0.03 wt% Ti, max. The aluminum alloy according to claim 1, comprising 15% by weight of impurities and Al. The aluminum alloy contains 0.01-0.05% by weight of Si, 0.05-0.11% by weight of Fe, 0.30-0.80% by weight of Cu, and 0.05-0.10% by weight. of Mn, 5.5-5.9 wt% Mg, 0.001-0.02 wt% Cr, 0-0.01 wt% Zn, 0.001-0.03 wt% Ti, max. The aluminum alloy according to claim 1, comprising 0.15% by weight of impurities and Al. The aluminum alloy comprises at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. 5. The aluminum alloy according to any one of 5. Aluminum alloy according to any one of claims 1 to 6, wherein the grain size of the Fe-containing component is less than 5 microns. Aluminum alloy according to any of claims 1 to 7, wherein the number density of Mg ₂ Si particles of the aluminum alloy microstructure is at least 500/mm ² . Aluminum alloy according to any of claims 1 to 8, wherein the aluminum alloy has a yield strength of at least 130 MPa. Aluminum alloy according to any of the preceding claims, wherein the aluminum alloy has an ultimate tensile strength of at least 300 MPa. Aluminum alloy according to any of claims 1 to 10, wherein the aluminum alloy has a total elongation of at least 5%. An aluminum alloy product comprising the aluminum alloy according to any one of claims 1 to 11. 13. The aluminum alloy product of claim 12, wherein the aluminum alloy product is produced by continuous casting, flash homogenization, hot rolling, and cold rolling. A method for manufacturing an aluminum alloy product, the method comprising:
continuous casting of an aluminum alloy to form a cast product, the aluminum alloy comprising: 0-0.30% by weight Si, 0.01-0.40% by weight Fe, 0-1.0% by weight; wt% Cu, 0.01-0.50 wt% Mn, 5.0-6.0 wt% Mg, 0-0.20 wt% Cr, 0-0.30 wt% Zn, 0 The continuous casting comprises ~0.25 wt% Ti, up to 0.15 wt% impurities, and Al;
optionally flash homogenizing the casting product;
hot rolling the cast product to produce a hot rolled product;
coiling the hot rolled product;
cold rolling the hot rolled product to produce a cold rolled product; and annealing the cold rolled product;
The method described above. 15. The aluminum alloy comprises at least one of Mg in an amount of 5.5% to 6.0% by weight and Cu in an amount of 0.30% to 1.0% by weight. Method described. 16. A method according to any of claims 14 or 15, wherein continuous casting comprises a solidification rate of at least 1[deg.]C/sec to produce the cast product. A method according to any of claims 14 to 16, wherein the annealing comprises batch annealing or continuous annealing. A method according to any of claims 14 to 17, wherein flash homogenization comprises heating the cast product at 400°C to 600°C for less than 10 minutes. 19. The method of any of claims 14 to 18, further comprising paint baking the cold rolled product after annealing to produce an aluminum alloy product. 20. The method of claim 19, wherein the yield strength of the aluminum alloy product increases by 5 MPa or more after paint baking.

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