EP4584413A1

EP4584413A1 - Rapid annealing and quenching of aluminum alloy products to reduce roping or ludering

Info

Publication number: EP4584413A1
Application number: EP22783242.5A
Authority: EP
Inventors: ChangOok SON; John Min HO; Monica KAPOOR; Debdutta ROY; Carolyn Grace KIDWELL; Doug KEIM; David Anthony Gaensbauer; Rajeev G. Kamat
Original assignee: Novelis Inc Canada
Current assignee: Novelis Inc Canada
Priority date: 2022-09-09
Filing date: 2022-09-09
Publication date: 2025-07-16
Also published as: WO2024054235A1; CN119855934A; CA3264350A1; JP2025530811A; KR20250040036A

Abstract

Described are methods for preparing rolled aluminum alloy products that are resistant to roping or Ludering effects upon stretching or forming. Rolled aluminum alloy products are subjected to a rapid annealing and quenching process prior to a cold rolling process. The rapid annealing and quenching processing described herein can replace batch annealing, commonly used for treating hot rolled aluminum alloy products prior to cold rolling, and can shorten processing times prior to cold rolling. The rapid annealing process can heat the rolled aluminum alloy product to a desired peak temperature very quickly, such as within a few seconds to a few minutes, and can quench the annealed aluminum alloy product quickly, such as within a few seconds to a few minutes.

Description

RAPID ANNEALING AND QUENCHING OF ALUMINUM ALLOY

PRODUCTS TO REDUCE ROPING OR LUDERING

FIELD

[0001] The present disclosure relates to metallurgy generally and more specifically to aluminum alloys and aluminum alloy products having low roping. In certain aspects, the disclosure also provides methods of making such products.

BACKGROUND

[0002] Aluminum alloy articles are desirable for use in a number of different applications, such as those where strength and durability are especially desirable. For example, aluminum alloys are commonly used for automotive skin panels and structural applications in place of steel. Because aluminum alloys are generally about 2.8 times less dense than steel, the use of such materials reduces the weight of the vehicle and allows for substantial improvements in its fuel economy. Even so, the use of currently available aluminum alloys in automotive and other applications poses certain challenges.

[0003] One such challenge for skin applications relates to forming automotive components with high elongation, improved surface quality (e.g., low roping), and high bendability or hemmability for assembly of the automotive components.

[0004] Roping is a strain-induced roughness or a macroscopic surface roughening defect. Roping can be characterized by visible lines that may be several centimeters wide along the rolling direction. Roping can result from materials being stretched along a transverse direction. The surface distribution of ridges and valleys can limit the use of the materials for outer panels in vehicle applications.

SUMMARY

[0005] The term embodiment and like terms are intended to refer broadly to all of the subject matter of this disclosure and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the claims below. Embodiments of the present disclosure covered herein are defined by the claims below, not this summary. This summary is a high-level overview of various aspects of the disclosure and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this disclosure, any or all drawings and each claim.

[0006] In an aspect, provided herein are methods for preparing rolled aluminum alloy products. The rolled aluminum alloy products may be resistant to roping or Ludering effects upon stretching or forming. The methods described may employ a process in which the aluminum alloy product is subjected to a rapid annealing and quenching process during processing to impart desirable properties to the aluminum alloy product. In some cases, the desirable properties can be imparted directly into the aluminum alloy product immediately upon being subjected to rapid annealing and quenching. In some cases, can be imparted and/or carry over into the aluminum alloy product upon subsequent processing, which may include rolling processes, solution heat-treatment processes, and/or aging processes, for example.

[0007] In an example, a method of this aspect may comprise providing a rolled aluminum alloy product, subjecting the rolled aluminum alloy product to a rapid annealing process to produce an annealed aluminum alloy product, and subjecting the annealed aluminum alloy product to a quenching process to produce a quenched aluminum alloy product. Optionally, the rapid annealing process comprises heating the rolled aluminum alloy product at a rate of up to 100 °C/s to a peak temperature of from 400 °C to 575 °C. Optionally, the quenching process comprises cooling portions of the annealed aluminum alloy at a rate of from -500 °C/s to -2 °C/s.

[0008] As noted above, additional processing may be performed after the rapid annealing and quenching processes. For example, some methods of this aspect may comprise or further comprise subjecting the quenched aluminum alloy product to a cold rolling process to produce a cold-rolled aluminum alloy product. As another example, some methods of this aspect may comprise or further comprise subjecting the aluminum alloy product to a solution heat-treatment process. Optionally, methods of this aspect may further comprise subjecting the aluminum alloy product to one or more of a cutting process, a forming process, an ageing process.

[0009] The rolled aluminum alloy products used in the methods of this aspect can be any suitable aluminum alloy product. For example, the rolled aluminum alloy product may be a hot-rolled aluminum alloy product. Optionally, the rolled aluminum alloy product has a thickness of from 1 mm to 8 mm. Optionally, the rolled aluminum alloy product may be a cold-rolled aluminum alloy product. Optionally, the rolled aluminum alloy product has a thickness of from 0.5 mm to 5 mm. Optionally, the rolled aluminum alloy product is at least partially unrecrystallized or is fully unrecrystallized. Optionally, the annealed aluminum alloy product is at least partially recrystallized or is fully recrystallized. In some examples, the rolled aluminum alloy product comprises a 6xxx series aluminum alloy or a 7xxx series aluminum alloy. In some examples, the rolled aluminum alloy product comprises a 2xxx series aluminum alloy or a 5xxx series aluminum alloy.

[0010] Upon or after quenching, the aluminum alloy product may include, comprise, or exhibit beneficial characteristics. In some examples, the presence of more or larger Mg2Si particles in an aluminum alloy product may result in a lower yield strength or reduced ultimate elongation, so it may be desirable to minimize or reduce the size of Mg2Si particles in the product, such as by processing according to the methods described herein. Optionally, the quenched aluminum alloy product exhibits a yield stress of from 70 MPa to 160 MPa. Optionally, the quenched aluminum alloy product exhibits a total elongation of from 20% to 30%. In some examples, the quenched aluminum alloy product exhibits an average Mg2Si particle size of less than 2 pm. Optionally, the quenched aluminum alloy product exhibits an electrical conductivity of from 40% IACS to 55% IACS. In some examples, electrical conductivity may be related to or correlate with an amount of dissolved solute (e.g., alloying elements) in the aluminum alloy matrix, including Mg and Si, and so a relatively lower electrical conductivity may indicate a relatively higher amount of dissolved Mg and Si and a relatively lower amount of Mg2Si particles in the aluminum alloy product. The dissolution of more Mg and Si into the aluminum matrix may also result in a reduction of average grain size. Optionally, the quenched aluminum alloy product exhibits an average grain size of 10 pm to 35 pm.

[0011] In some example, magnetic induction heating may be used for the rapid annealing process. Optionally, the rapid annealing process comprises exposing the annealed aluminum alloy product to a quenching fluid after a heating process.

[0012] It will be appreciated that the rapid annealing process does not comprise a batch or coil annealing process, such as where an entire coil of a rolled aluminum alloy is heated at the same time, such as in a furnace. Similarly, it will be appreciated that the quenching process does not comprise a batch or coil cooling process, such as where an entire coil of a rolled aluminum alloy is reduced in temperature from the heated temperature, such as in the annealing furnace. In some examples, subjecting the rolled aluminum alloy product to the rapid annealing process comprises uncoiling the rolled aluminum alloy. In some examples, the rapid annealing process is a continuous heating process that heats only portions of the rolled aluminum alloy product at a time. Optionally, the quenching process is a continuous cooling process that cools only portions of the annealed aluminum alloy product at a time. In some examples, after the rapid annealing process and the quenching process, the rolled aluminum alloy is re-coiled. Optionally, the rapid annealing process comprises passing the rolled aluminum alloy product through a heating system at a rate of from 5 m/min to 600 m/min. Optionally, the quenching process comprises passing the annealed aluminum alloy product through a quenching system at a rate of from 5 m/min to 600 m/min.

[0013] The rapid annealing processes described herein may be performed quickly, such as within a few minutes or within tens of minutes. In some examples, the rolled aluminum alloy product is subjected to temperatures greater than 100 °C during the rapid annealing and quenching processes for at most 5 minutes. Optionally, methods of this aspect may further comprise holding the rolled aluminum alloy product within 20 °C of the peak temperature for up to 1 minute prior to the quenching process.

[0014] Aluminum alloy products prepared according to the methods described herein are also provided by the present disclosure. In some examples, an aluminum alloy product comprises a formed or stretched aluminum alloy sheet product comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy, such as having a surface arithmetical mean height (Sa) of the formed or stretched aluminum alloy sheet product of at most 10 pm. Optionally, a thickness of the formed or stretched aluminum alloy sheet product may be from 1.00 mm to 3.5 mm. In some examples, the formed or stretched aluminum alloy sheet product comprises a 6xxx series aluminum alloy. Optionally the formed or stretched aluminum alloy sheet product is free or substantially free of surface roping bands. In some examples, the formed or stretched aluminum alloy sheet product comprises a 5xxx series aluminum alloy. Optionally, the formed or stretched aluminum alloy sheet product is free or substantially free of surface Luders bands.

[0015] Other objects and advantages will be apparent from the following detailed description of non-limiting examples.

BRIEF DESCRIPTION OF THE FIGURES

[0016] The specification makes reference to the following appended figures, in which use of like reference numerals in different figures is intended to illustrate like or analogous components. [0017] FIG. 1 provides a schematic overview of an example method for making a rolled aluminum alloy product.

[0018] FIG. 2 provides a schematic overview of temperatures of an aluminum alloy product during preparation.

[0019] FIG. 3 provides a schematic illustration of rapid annealing and quenching of an aluminum alloy product.

[0020] FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, and FIG. 4E provide optical micrographs comparing the grain structure of samples subjected to rapid annealing and quenching with samples subjected to batch annealing.

[0021] FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D, and FIG. 5E provide optical micrographs comparing the precipitates of samples subjected to rapid annealing and quenching with samples subjected to batch annealing.

[0022] FIG. 6 provides scanning electron micrograph images comparing cross sections of a samples subjected to rapid annealing and quenching using different techniques.

[0023] FIG. 7 provides data showing yield stress of samples subjected to rapid annealing and quenching and a sample subjected to batch annealing.

[0024] FIG. 8 provides data showing total elongation of samples subjected to rapid annealing and quenching and a sample subjected to batch annealing.

[0025] FIG. 9 shows optical micrographs of a cross section of samples subjected to rapid annealing and quenching and batch annealing.

[0026] FIG. 10 provides 50 pm wide micrograph images of samples subjected to rapid annealing and quenching or batch annealing, showing the amount and size of precipitates.

[0027] FIG. 11 provides data showing the yield stress for annealed, cold rolled, and solution heat treated samples after room temperature aging (T4 temper condition) and artificial aging/paint baking (T81 temper condition).

[0028] FIG. 12 provides data showing the total elongation for annealed, cold rolled, and solution heat treated samples after room temperature aging (T4 temper condition).

[0029] FIG. 13 provides electrical conductivity results for rolled aluminum alloy product samples subjected to rapid annealing and quenching.

[0030] FIG. 14A and FIG. 14B provide micrograph images showing a through thickness grain structure of samples annealed to different temperatures at different heating rates.

[0031] FIG. 15A and FIG. 15B provide micrograph images of samples subjected to rapid annealing to different peak temperatures at different heating rates to show the amount and size of precipitates. [0032] FIG. 16 provides electrical conductivity data of samples subjected to rapid annealing to different peak temperatures.

[0033] FIG. 17 provides measured yield stress of samples subjected to rapid annealing to different peak temperatures.

[0034] FIG. 18 provides measured maximum axial strain of samples subjected to rapid annealing to different peak temperatures.

DETAILED DESCRIPTION

[0035] Described herein are methods for preparing rolled aluminum alloy products that are resistant to roping or Ludering effects upon stretching or forming. Roping is the development of a series of ridges and valleys of various depths that extend along the rolling direction when certain aluminum alloys, such as 6xxx series alloys or 7xxx series alloys, are stretched in the transverse direction, for example. These ridges and valleys give an undesirable surface appearance to the formed or stretched aluminum alloy products. Ludering is another undesirable surface characteristic that develops in certain aluminum alloys, such as 5xxx series alloys or other Mg containing alloys, where dislocations propagate through the aluminum crystal lattice during forming or stretching and create Ludering bands. The present application provides processing techniques for rolled aluminum alloy products that limit roping or Ludering by subjecting the rolled aluminum alloy products to a rapid annealing and quenching process prior to one or more cold rolling processes.

[0036] The rapid annealing and quenching processing described herein can replace batch annealing, commonly used for treating hot-rolled aluminum alloy products prior to cold rolling, and can shorten processing times prior to the cold rolling. For example, batch annealing can take many hours (e.g., 20 hours or more) to process, and generally involves placing coils of hot-rolled aluminum alloy products into a furnace and heating them to an annealing temperature and holding for some time before allowing the coils to cool to ambient temperature. In contrast, the rapid annealing and quenching processing described herein can process a coil of a hot-rolled aluminum alloy product very quickly, such as within 1 hour or less. The rapid annealing and quenching processing described herein can also or alternatively be used as an interannealing process between cold rolling passes.

[0037] During the rapid annealing and quenching processing, which can be considered a continuous annealing and quenching process or, in some cases, a semi-continuous annealing and quenching process, the material can be uncoiled (if coiled), passed through a rapid annealing system and a quenching system and then be re-coiled, optionally, for subsequent processing. The rapid annealing process can heat the portion of the aluminum alloy product passing through the rapid annealing system to a desired peak temperature very quickly, such as within a few seconds to a few minutes. Following this, the quenching process can cool the portion of the annealed aluminum alloy product passing through the quenching system very quickly, such as within a few seconds to a few minutes. In contrast, batch annealing processes can take many hours to heat a coil of aluminum to ambient temperature to annealing temperature and/or cool a coil of aluminum to ambient temperature. Overall, the amount of time that any portion of the rolled aluminum alloy product is subjected to the annealing and quenching treatment according to the processes described herein can be as short as a few seconds or up to a few minutes (e.g., 10 minutes or less).

[0038] The rapid annealing and quenching processing can result in modification of the properties of the rolled aluminum alloy product that provide various enhancements. For example, the rolled aluminum alloy product can undergo recrystallization, at least in part, where deformed grains of aluminum are replaced by defect-free grains during the annealing process. In some examples, the rolled aluminum alloy product can be at least partially unrecrystallized or fully unrecrystallized prior to rapid annealing and quenching and/or can be at least partially recrystallized or fully recrystallized after rapid annealing and quenching. The rapid annealing and quenching process can result in the annealed and quenched aluminum alloy product having a finer grain structure (e.g., smaller average grain size) and more uniform grain structure (e.g., narrower grain size distribution) and different mechanical or strength characteristics as compared to the aluminum alloy product prior to annealing and quenching. These characteristics can propagate through subsequent cold rolling and other processing and into the final product.

[0039] In some examples, after rapid annealing and quenching, the aluminum alloy product can exhibit an average grain size of 10 pm to 35 pm, such as from 10 pm to 15 pm, 15 pm to 20 pm, 20 pm to 25 pm, 25 pm to 30 pm, or 30 pm to 35 pm. In some examples, after rapid annealing and quenching, the aluminum alloy product can exhibit a yield stress of from 70 MPa to 160 MPa, such as from 70 MPa to 80 MPa, from 80 MPa to 90 MPa, from 90 MPa to 100 MPa, from 100 MPa to 110 MPa, from 110 MPa to 120 MPa, from 120 MPa to 130 MPa, from 130 MPa to 140 MPa, from 140 MPa to 150 MPa, or from 150 MPa to 160 MPa. In some examples, after rapid annealing and quenching, the aluminum alloy product can exhibit a total elongation of from 20% to 30%, such as from 20% to 21%, from 21% to 22%, from 22% to 23%, from 23% to 24%, from 24% to 25%, from 25% to 26%, from 26% to 27%, from 27% to 28%, from 28% to 29%, or from 29% to 30%. [0040] Additionally, the rapid annealing and quenching processing can serve to reduce the size of precipitates, such as Mg2Si particles for example, that may be present in the aluminum alloy product prior to annealing and quenching. In the case of a hot-rolled aluminum alloy product, the precipitates can be very coarse, but after the rapid annealing and quenching processing, considerable amounts, or even all or almost all, of the precipitates can be dissolved in the aluminum matrix, impacting electrical conductivity and other properties (e.g., strength). Again, these properties can propagate through subsequent cold rolling and other processing. In some cases, with the size of precipitates reduced as compared to a hot- rolled aluminum alloy product, a solution heat treatment process applied after cold rolling can be completed in a shorter amount of time, allowing for increases in line speed of a solutionizing process and higher throughput.

[0041] In some examples, after rapid annealing and quenching, the aluminum alloy product can exhibit an average precipitate particle size (e.g., Mg2Si particle size) of less than 2 pm, such as an equivalent circular diameter of less than 2 pm or a cross-sectional length of less than 2 pm. In some examples, the average precipitate particle size is from 0.1 pm to 2 pm, such as from 0.1 pm to 0.2 pm, from 0.2 pm to 0.3 pm, from 0.3 pm to 0.4 pm, from 0.4 pm to 0.5 pm, from 0.5 pm to 0.6 pm, from 0.6 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 0.1 pm to 2 pm, from 1.8 pm to 1.9 pm, or from 1.9 pm to 2 pm. In some examples, after rapid annealing and quenching, the aluminum alloy product can exhibit an electrical conductivity of from 40% IACS to 55% IACS, such as from 40% IACS to 41% IACS, from 41% IACS to 42% IACS, from 42% IACS to 43% IACS, from 43% IACS to 44% IACS, from 44% IACS to 45% IACS, from 45% IACS to 46% IACS, from 46% IACS to 47% IACS, from 47% IACS to 48% IACS, from 48% IACS to 49% IACS, from 49% IACS to 50% IACS, from 50% IACS to 51% IACS, from 51% IACS to 52% IACS, from 52% IACS to 53% IACS, from 53% IACS to 54% IACS, or from 54% IACS to 55% IACS.

[0042] It will be appreciated that the rapid annealing and quenching processes described herein are different from and generally do not comprise a batch annealing process, such as where an entire coil of a rolled aluminum product is subjected to annealing while in a coiled configuration. As noted above, the rapid annealing and quenching process provides advantages over batch annealing, including faster annealing and cooling processing times, and differences in grain and precipitate structure. Together, the rapid annealing and quenching processing can be useful for controlling various characteristics of the aluminum alloy product, while limiting, reducing, or eliminating the effects of roping or Ludering that may otherwise occur upon forming or stretching of the processed aluminum alloy product in the absence of the rapid annealing and quenching processing. For example, surface arithmetical mean height (Sa) may provide a measure characterizing the presence or absence of roping or Ludering. Techniques described herein are useful for generating an aluminum alloy product, such as a 5xxx series, 6xxx series, or 7xxx series aluminum alloy sheet product that, after forming or stretching, exhibits a surface arithmetical mean height (Sa) of at most

10 pm, such as up to 0.5 pm, up to 1 pm, up to 2 pm, up to 3 pm, up to 4 pm, up to 5 pm, up to 6 pm, up to 7 pm, up to 8 pm, up to 9 pm, or up to 10 pm.

Definitions and Descriptions:

[0043] As used herein, the terms “invention,” “the invention,” “this invention” and “the present invention” are intended to refer broadly to all of the subject matter of this patent application and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the patent claims below.

[0044] In this description, reference is made to alloys identified by AA numbers and other related designations, such as “series” or “7xxx.” For an understanding of the number designation system most commonly used in naming and identifying aluminum and its alloys, see “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys” or “Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot,” both published by The Aluminum Association.

[0045] As used herein, a plate generally has a thickness of greater than about 15 mm. For example, a plate may refer to an aluminum product having a thickness of greater than about 15 mm, greater than about 20 mm, greater than about 25 mm, greater than about 30 mm, greater than about 35 mm, greater than about 40 mm, greater than about 45 mm, greater than about 50 mm, or greater than about 100 mm.

[0046] As used herein, a shate (also referred to as a sheet plate) generally has a thickness of from about 4 mm to about 15 mm. For example, a shate may have a thickness of about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about

11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm. [0047] As used herein, a sheet generally refers to an aluminum product having a thickness of less than about 4 mm. For example, a sheet may have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, or less than about 0.3 mm (e.g., about 0.2 mm).

[0048] Reference may be made in this application to alloy temper or condition. For an understanding of the alloy temper descriptions most commonly used, see “American National Standards (ANSI) H35 on Alloy and Temper Designation Systems.” An F condition or temper refers to an aluminum alloy as fabricated. An O condition or temper refers to an aluminum alloy after annealing. An Hxx condition or temper, also referred to herein as an H temper, refers to a non-heat treatable aluminum alloy after cold rolling with or without thermal treatment (e.g., annealing). Suitable H tempers include HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8, or HX9 tempers. A T1 condition or temper refers to an aluminum alloy cooled from hot working and naturally aged (e.g., at room temperature). A T2 condition or temper refers to an aluminum alloy cooled from hot working, cold worked and naturally aged. A T3 condition or temper refers to an aluminum alloy solution heat treated, cold worked, and naturally aged. A T4 condition or temper refers to an aluminum alloy solution heat treated and naturally aged. A T5 condition or temper refers to an aluminum alloy cooled from hot working and artificially aged (at elevated temperatures). A T6 condition or temper refers to an aluminum alloy solution heat treated and artificially aged. A T7 condition or temper refers to an aluminum alloy solution heat treated and artificially overaged. A T8x condition or temper refers to an aluminum alloy solution heat treated, cold worked, and artificially aged. A T9 condition or temper refers to an aluminum alloy solution heat treated, artificially aged, and cold worked. A W condition or temper refers to an aluminum alloy after solution heat treatment.

[0049] As used herein, terms such as “cast metal product,” “cast product,” “cast aluminum alloy product,” and the like are interchangeable and refer to a product produced by direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (including, for example, by use of a twin belt caster, a twin roll caster, a block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method.

[0050] As used herein, the meaning of “room temperature” can include a temperature of from about 15 °C to about 30 °C, for example about 15 °C, about 16 °C, about 17 °C, about 18 °C, about 19 °C, about 20 °C, about 21 °C, about 22 °C, about 23 °C, about 24 °C, about 25 °C, about 26 °C, about 27 °C, about 28 °C, about 29 °C, or about 30 °C. As used herein, the meaning of “ambient conditions” can include temperatures of about room temperature, relative humidity of from about 20% to about 100%, and barometric pressure of from about 975 millibar (mbar) to about 1050 mbar. For example, relative humidity can be about 20%, about 21%, about 22%, about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about 29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%, about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about 42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%, about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about 55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%, about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about 68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%, about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%, or anywhere in between. For example, barometric pressure can be about 975 mbar, about 980 mbar, about 985 mbar, about 990 mbar, about 995 mbar, about 1000 mbar, about 1005 mbar, about 1010 mbar, about 1015 mbar, about 1020 mbar, about 1025 mbar, about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or anywhere in between.

[0051] All ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g. 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10. Unless stated otherwise, the expression “up to” when referring to the compositional amount of an element means that element is optional and includes a zero percent composition of that particular element. Unless stated otherwise, all compositional percentages are in weight percent (wt.%).

[0052] As used herein, the meaning of “a,” “an,” and “the” includes singular and plural references unless the context clearly dictates otherwise.

[0053] In the following examples, aluminum alloy products and their components may be described in terms of their elemental composition in weight percent (wt.%). In each alloy, the remainder is aluminum, with a maximum wt.% of 0.15% for the sum of all impurities.

[0054] Incidental elements, such as grain refiners and deoxidizers, or other additives may be present in the invention and may add other characteristics on their own without departing from or significantly altering the alloy described herein or the characteristics of the alloy described herein.

[0055] Unavoidable impurities, including materials or elements may be present in an alloy in minor amounts due to inherent properties of aluminum or leaching from contact with processing equipment. Some alloys, as described, may contain no more than about 0.25 wt.% of any element besides the alloying elements, incidental elements, and unavoidable impurities.

Methods of Producing the Alloys and Aluminum Alloy Products

[0056] The aluminum alloy products described herein can be prepare using suitable methods. For example, aluminum alloys may be cast, homogenized, hot-rolled, annealed, cold-rolled, heat treated, formed, or the like to generate aluminum alloy products.

[0057] FIG. 1 provides an overview of an example method of making an aluminum alloy product. The method of FIG. 1 begins at 105, where an aluminum alloy 106 is cast to form a cast aluminum alloy product 107, such as an ingot or other cast product. At 110, the cast aluminum alloy product 107 is homogenized to form a homogenized aluminum alloy product 111. At 115, the homogenized aluminum alloy product 111 is subjected to one or more hot rolling passes. The hot-rolled aluminum alloy product may optionally be coiled and subjected to batch annealing processes (not illustrated in FIG. 1), or other annealing processes as described herein. At 120 the hot-rolled aluminum alloy product is subjected to one or more cold rolling passes to form a rolled aluminum alloy product 112, which may correspond to an aluminum alloy article, such as an aluminum alloy plate, an aluminum alloy shate, or an aluminum alloy sheet. As described herein in further detail, a rapid annealing and quenching process can be applied to the hot-rolled aluminum alloy product prior to cold rolling or between multiple cold rolling steps, and such processing is not shown in FIG. 1. Optionally, the rolled aluminum alloy product 112 is subjected to additional processing steps, as described below, to form an aluminum alloy article.

[0058] Non-limiting examples of casting processes include a direct chill (DC) casting process or a continuous casting (CC) process. For example, FIG. 1 depicts a schematic illustration of a DC casting process at 105, but other casting processes can be used. A continuous casting system can include a pair of moving opposed casting surfaces (e.g., moving opposed belts, rolls or blocks), a casting cavity between the pair of moving opposed casting surfaces, and a molten metal injector. The molten metal injector can have an end opening from which molten metal can exit the molten metal injector and be injected into the casting cavity.

[0059] A cast aluminum alloy product, such as a cast ingot, cast slab, or other cast product, can be processed by any desirable techniques. Optionally, the processing steps can be used to prepare rolled aluminum alloy products, such as aluminum alloy sheets. Example optional processing steps include, but are not limited to, homogenization, hot rolling, cold rolling, annealing, solution heat treatment, and pre-aging.

[0060] In a homogenization step, a cast product may be heated to a temperature ranging from about 400 °C to about 600 °C. For example, the cast product can be heated to a temperature of about 400 °C, about 410 °C, about 420 °C, about 430 °C, about 440 °C, about 450 °C, about 460 °C, about 470 °C, about 480 °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. The product may then be allowed to soak (i.e., held at the indicated temperature) for a period of time to form a homogenized product. In some examples, the total time for the homogenization step, including the heating and soaking phases, can be up to 24 hours. For example, the product can be heated up to 500 °C to 600 °C, and soaked, for a total time of up to 18 hours for the homogenization step. Optionally, the product can be heated to below 490 °C and soaked, for a total time of greater than 18 hours for the homogenization step. In some cases, the homogenization step comprises multiple processes. In some non-limiting examples, the homogenization step includes heating a cast product to a first temperature for a first period of time followed by heating to a second temperature for a second period of time. For example, a cast product can be heated to about 465 °C for about 3.5 hours and then heated to about 480 °C for about 6 hours.

[0061] Following a homogenization step, a hot rolling step can be optionally performed. Prior to the start of hot rolling, the homogenized product can be allowed to cool to a temperature between 300 °C to 450 °C. For example, the homogenized product can be allowed to cool to a temperature of between 325 °C to 425 °C or from 350 °C to 400 °C. The homogenized product can then be hot rolled at a temperature between 300 °C to 450 °C to form a hot rolled plate, a hot rolled shate or a hot rolled sheet having a gauge between 3 mm and 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, or anywhere in between). [0062] Optionally, the cast product can be a continuously cast product that can be allowed to cool to a temperature between 300 °C to 450 °C. For example, the continuously cast product can be allowed to cool to a temperature of between 325 °C to 425 °C or from 350 °C to 400 °C. The continuously cast products can then be hot rolled at a temperature between 300 °C to 450 °C to form a hot rolled plate, a hot rolled shate or a hot rolled sheet having a gauge between 3 mm and 200 mm (e.g., 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, or anywhere in between). During hot rolling, temperatures and other operating parameters can be controlled so that the temperature of the hot rolled intermediate product upon exit from the hot rolling mill is no more than 470 °C, no more than 450 °C, no more than 440 °C, or no more than 430 °C.

[0063] Cast, homogenized, or hot-rolled products can be optionally cold rolled using cold rolling mills into thinner products, such as a cold rolled sheet. The cold rolled product can have a gauge between about 0.5 to 10 mm, e.g., between about 0.7 to 6.5 mm. Optionally, the cold rolled product can have a gauge of 0.5 mm, 1.0 mm, 1.5 mm, 2.0 mm, 2.5 mm, 3.0 mm, 3.5 mm, 4.0 mm, 4.5 mm, 5.0 mm, 5.5 mm, 6.0 mm, 6.5 mm, 7.0 mm, 7.5 mm, 8.0 mm, 8.5 mm, 9.0 mm, 9.5 mm, or 10.0 mm. The cold rolling can be performed to result in a final gauge thickness that represents a gauge reduction of up to 85% (e.g., up to 10%, up to 20%, up to 30%, up to 40%, up to 50%, up to 60%, up to 70%, up to 80%, or up to 85% reduction) as compared to a gauge prior to the start of cold rolling. Optionally, an interannealing step can be performed during the cold rolling step, such as where a first cold rolling process is applied, followed by an annealing process (interannealing), followed by a second cold rolling process. The interannealing step can be performed at a temperature of 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 interannealing step comprises multiple processes. In some non-limiting examples, the interannealing step includes heating the partially cold rolled product to a first temperature for a first period of time followed by heating to a second temperature for a second period of time. For example, the partially cold rolled product can be heated to about 410 °C for about 1 hour and then heated to about 330 °C for about 2 hours. Other interannealing processing, such as rapid annealing and quenching, can be applied, as described elsewhere in this application. [0064] Subsequently, a cast, homogenized, or rolled product can optionally undergo a solution heat treatment step. The solution heat treatment step can be any suitable treatment for the product that results in solutionizing of soluble particles. The cast, homogenized, or rolled product can be heated to a peak metal temperature (PMT) of up to 590 °C (e.g., from 400 °C to 590 °C) and soaked for a period of time at the PMT to form a hot product. For example, the cast, homogenized, or rolled product can be soaked at 480 °C for a soak time of up to 30 minutes (e.g., 0 seconds, 60 seconds, 75 seconds, 90 seconds, 5 minutes, 10 minutes, 20 minutes, 25 minutes, or 30 minutes). After heating and soaking, the hot product is rapidly cooled at rates greater than 200 °C/s to a temperature between 500 and 200 °C to form a heat- treated product. In one example, the hot product is cooled at a quench rate of above 200 °C/second at temperatures between 450 °C and 200 °C. Optionally, the cooling rates can be faster in other cases. Optionally, the temperature can be lower in other cases. In one example, the hot product is cooled at a quench rate of above 200 °C/second at temperatures between 450 °C and 200 °C.

[0065] After quenching, the heat-treated product can optionally undergo a pre-aging treatment by reheating before coiling. The pre-aging treatment can be performed at a temperature of from about 70 °C to about 125 °C for a period of time of up to 6 hours. For example, the pre-aging treatment can be performed at a temperature of about 70 °C, about 75 °C, about 80 °C, about 85 °C, about 90 °C, about 95 °C, about 100 °C, about 105 °C, about 110 °C, about 115 °C, about 120 °C, or about 125 °C. Optionally, the pre-aging treatment can be performed for about 30 minutes, about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, or about 6 hours. The pre-aging treatment can be carried out by passing the heat-treated product through a heating device, such as a device that emits radiant heat, convective heat, induction heat, infrared heat, or the like.

[0066] The cast products described herein can be used to make products in the form of sheets, plates, or other suitable products. For example, plates including the products as described herein can be prepared by processing an ingot in a homogenization step or casting a product in a continuous caster followed by a hot rolling step. In the hot rolling step, the cast product can be hot rolled to a 200 mm thick gauge or less (e.g., from about 10 mm to about 200 mm). For example, the cast product can be hot rolled to a plate having a final gauge thickness of about 10 mm to about 175 mm, about 15 mm to about 150 mm, about 20 mm to about 125 mm, about 25 mm to about 100 mm, about 30 mm to about 75 mm, or about 35 mm to about 50 mm. In some cases, plates may be rolled into thinner metal products, such as sheets. Methods of Using the Disclosed Aluminum Alloy Products

[0067] The aluminum alloy products described herein can be used in automotive applications and other transportation applications, including aircraft and railway applications. For example, the disclosed aluminum alloy products can be used to prepare automotive structural parts, such as bumpers, side beams, roof beams, cross beams, pillar reinforcements (e.g., A-pillars, B-pillars, and C-pillars), inner panels, outer panels, side panels, inner hoods, outer hoods, or trunk lid panels. The aluminum alloy products and methods described herein can also be used in aircraft or railway vehicle applications, to prepare, for example, external and internal panels.

[0068] 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 prepare housings for electronic devices, including mobile phones and tablet computers. In some examples, the aluminum alloy products can be used to prepare housings for the outer casing of mobile phones (e.g., smart phones), tablet bottom chassis, and other portable electronics.

Methods of Treating Metals and Metal Alloys

[0069] Described herein are methods of treating metals and metal alloys, including aluminum, aluminum alloys, magnesium, magnesium alloys, magnesium composites, and steel, among others, and the resultant treated metals and metal alloys. In some examples, the metals for use in the methods described herein include aluminum alloys, for example, Ixxx series aluminum alloys, 2xxx series aluminum alloys, 3xxx series aluminum alloys, 4xxx series aluminum alloys, 5xxx series aluminum alloys, 6xxx series aluminum alloys, 7xxx series aluminum alloys, or 8xxx series aluminum alloys. In some examples, the materials for use in the methods described herein include non-ferrous materials, including aluminum, aluminum alloys, magnesium, magnesium-based materials, magnesium alloys, magnesium composites, titanium, titanium-based materials, titanium alloys, copper, copper-based materials, composites, sheets used in composites, or any other suitable metal, non-metal, or combination of materials. Monolithic as well as non-monolithic, such as roll-bonded materials, cladded alloys, clad layers, composite materials, such as but not limited to carbon fiber-containing materials, or various other materials are also useful with the methods described herein. In some examples, aluminum alloys containing iron are useful with the methods described herein. [0070] By way of non-limiting example, exemplary Ixxx series aluminum alloys for use in the methods described herein can include AA1100, AA1100A, AA1200, AA1200A, AA1300, AA1110, AA1120, AA1230, AA1230A, AA1235, AA1435, AA1145, AA1345, AA1445, AA1150, AA1350, AA1350A, AA1450, AA1370, AA1275, AA1185, AA1285, AA1385, AA1188, AA1190, AA1290, AA1193, AA1198, or AA1199.

[0071] Non-limiting exemplary 2xxx series aluminum alloys for use in the methods described herein can include AA2001, AA2002, AA2004, AA2005, AA2006, AA2007, AA2007A, AA2007B, AA2008, AA2009, AA2010, AA2011, AA2011A, AA2111, AA2111A, AA2111B, AA2012, AA2013, AA2014, AA2014A, AA2214, AA2015, AA2016, AA2017, AA2017A, AA2117, AA2018, AA2218, AA2618, AA2618A, AA2219, AA2319, AA2419, AA2519, AA2021, AA2022, AA2023, AA2024, AA2024A, AA2124, AA2224, AA2224A, AA2324, AA2424, AA2524, AA2624, AA2724, AA2824, AA2025, AA2026, AA2027, AA2028, AA2028A, AA2028B, AA2028C, AA2029, AA2030, AA2031, AA2032, AA2034, AA2036, AA2037, AA2038, AA2039, AA2139, AA2040, AA2041, AA2044, AA2045, AA2050, AA2055, AA2056, AA2060, AA2065, AA2070, AA2076, AA2090, AA2091, AA2094, AA2095, AA2195, AA2295, AA2196, AA2296, AA2097, AA2197, AA2297, AA2397, AA2098, AA2198, AA2099, or AA2199.

[0072] Non-limiting exemplary 3xxx series aluminum alloys for use in the methods described herein can include AA3002, AA3102, AA3003, AA3103, AA3103A, AA3103B, AA3203, AA3403, AA3004, AA3004A, AA3104, AA3204, AA3304, AA3005, AA3005A, AA3105, AA3105A, AA3105B, AA3007, AA3107, AA3207, AA3207A, AA3307, AA3009, AA3010, AA3110, AA3011, AA3012, AA3012A, AA3013, AA3014, AA3015, AA3016, AA3017, AA3019, AA3020, AA3021, AA3025, AA3026, AA3030, AA3130, or AA3065. [0073] Non-limiting exemplary 4xxx series aluminum alloys for use in the methods described herein can include AA4004, AA4104, AA4006, AA4007, AA4008, AA4009, AA4010, AA4013, AA4014, AA4015, AA4015A, AA4115, AA4016, AA4017, AA4018, AA4019, AA4020, AA4021, AA4026, AA4032, AA4043, AA4043A, AA4143, AA4343, AA4643, AA4943, AA4044, AA4045, AA4145, AA4145A, AA4046, AA4047, AA4047A, or AA4147.

[0074] Non-limiting exemplary 5xxx series aluminum alloys for use in the methods described herein product can include AA5182, AA5183, AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106, AA5010, AA5110, AA5110A, AA5210, AA5310, AA5016, AA5017, AA5018, AA5018A, AA5019, AA5019A, AA5119, AA5119A, AA5021, AA5022, AA5023, AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042, AA5043, AA5049, AA5149, AA5249, AA5349, AA5449, AA5449A, AA5050, AA5050A, AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA5254, AA5354, AA5454, AA5554, AA5654, AA5654A, AA5754, AA5854, AA5954, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA5070, AA5180, AA5180A, AA5082, AA5182, AA5083, AA5183, AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

[0075] Non-limiting exemplary 6xxx series aluminum alloys for use in the methods described herein can include AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, AA6205, AA6305, AA6006, AA6106, AA6206, AA6306, AA6008, AA6009, AA6010, AA6110, AA6110A, AA6011, AA6111, AA6012, AA6012A, AA6013, AA6113, AA6014, AA6015, AA6016, AA6016A, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA6027, AA6028, AA6031, AA6032, AA6033, AA6040, AA6041, AA6042, AA6043, AA6151, AA6351, AA6351A, AA6451, AA6951, AA6053, AA6055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A, AA6261, AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, AA6963, AA6064, AA6064A, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091, or AA6092.

[0076] Non-limiting exemplary 7xxx series aluminum alloys for use in the methods described herein can include AA7011, AA7019, AA7020, AA7021, AA7039, AA7072, AA7075, AA7085, AA7108, AA7108A, AA7015, AA7017, AA7018, AA7019A, AA7024, AA7025, AA7028, AA7030, AA7031, AA7033, AA7035, AA7035A, AA7046, AA7046A, AA7003, AA7004, AA7005, AA7009, AA7010, AA7011, AA7012, AA7014, AA7016, AA7116, AA7122, AA7023, AA7026, AA7029, AA7129, AA7229, AA7032, AA7033, AA7034, AA7036, AA7136, AA7037, AA7040, AA7140, AA7041, AA7049, AA7049A, AA7149, AA7204, AA7249, AA7349, AA7449, AA7050, AA7050A, AA7150, AA7250, AA7055, AA7155, AA7255, AA7056, AA7060, AA7064, AA7065, AA7068, AA7168, AA7175, AA7475, AA7076, AA7178, AA7278, AA7278A, AA7081, AA7181, AA7185, AA7090, AA7093, AA7095, or AA7099. [0077] Non-limiting exemplary 8xxx series aluminum alloys for use in the methods described herein can include AA8005, AA8006, AA8007, AA8008, AA8010, AA8011, AA8011A, AA8111, AA8211, AA8112, AA8014, AA8015, AA8016, AA8017, AA8018, AA8019, AA8021, AA8021A, AA8021B, AA8022, AA8023, AA8024, AA8025, AA8026, AA8030, AA8130, AA8040, AA8050, AA8150, AA8076, AA8076A, AA8176, AA8077, AA8177, AA8079, AA8090, AA8091, or AA8093.

[0078] FIG. 2 provides a plot showing example temperatures of a cast aluminum alloy product during various stages of a manufacturing process in accordance with some embodiments. As part of an initial casting stage 205, where molten aluminum alloy is formed into an ingot, cast article, or other solid object or metal product, the molten aluminum alloy may be cooled and/or solidified by a process involving quenching or cooling the metal by exposing the aluminum alloy to water or an aqueous solution, such as in a direct chill casting process or in a continuous casting process that includes quenching immediately after casting.

[0079] Following the casting stage 205, the aluminum alloy product may be subjected to a homogenization process 210, where the aluminum alloy is heated to a temperature less than the melting or solidus temperature. Optionally, the aluminum alloy product is heated to a temperature at which the base aluminum metal and any alloying elements form a solid solution.

[0080] Following the homogenization process 210, the aluminum alloy product may be exposed to one or more processes that may, for example, form desirable microcrystalline structures within the aluminum alloy product while elongating the aluminum alloy product. Such processes may correspond to hot rolling 215 and/or cold rolling 230, for example, such as to form shates, plates, or sheets from an aluminum alloy ingot or other cast article or aluminum alloy product.

[0081] In some embodiments, exposing an aluminum alloy product at an elevated temperature to a solution, such as water, an aqueous solution, or a gas-phase solution, in a quenching or cooling process may be used to reduce the temperature of the aluminum alloy product to a temperature desirable or useful for a subsequent process. For example, exposing the aluminum alloy product to water or an aqueous solution may be useful for cooling the aluminum alloy product between hot rolling process 215 and cold rolling process 230.

[0082] Following the hot rolling process 215 and/or an optional cold rolling process 220, the aluminum alloy product may be subjected to rapid annealing and quenching process 225, where the aluminum alloy product is quickly heated to and optionally held at or near a peak temperature for a short duration and then rapidly cooled to generate an annealed aluminum alloy product with at least partial recrystallization of the aluminum alloy grains. It will be appreciated that, in some cases, optional cold rolling process 220 is not used and the aluminum alloy product is subjected to rapid annealing and quenching process 225 following hot rolling process 215, optionally without allowing the aluminum alloy product to return all the way to ambient temperature, and prior to any cold rolling. In some examples, optional cold rolling process 220 takes place at ambient temperature or room temperature or a temperature above ambient temperature or room temperature. In some examples, the aluminum alloy product is at ambient temperature or room temperature or a temperature above ambient temperature or room temperature prior to rapid annealing and quenching process 225. For example, after hot rolling, the aluminum alloy product may not cool all the way down to ambient temperature or room temperature or may be heated by cold rolling process 220 or cold rolling process 220 may take place at a temperature above ambient temperature or room temperature. In cases where the aluminum alloy product is at a temperature above ambient temperature or room temperature, this can result in less heat having to be added to the aluminum alloy product during the rapid annealing and quenching process 225 to achieve a target annealing temperature than if the aluminum alloy product were at ambient temperature or room temperature.

[0083] The aluminum alloy product is subjected to cold rolling process 230 after the rapid annealing and quenching process 225. Further details of rapid annealing and quenching process 225 are described herein. When optional cold rolling process 220 is used, a second rapid annealing and quenching process can be optionally used, such as prior to optional cold rolling process 220. In some examples, cold rolling process 230 takes place at ambient temperature or room temperature or a temperature above ambient temperature or room temperature.

[0084] A variety of different peak temperatures may be used for the rapid annealing processes described herein. In general, peak temperatures of from 400 °C to 575 °C may be used. Optionally, the peak temperature may be from 400 °C to 405 °C, from 405 °C to 410 °C, from 410 °C to 415 °C, from 415 °C to 420 °C, from 420 °C to 425 °C, from 425 °C to 430 °C, from 430 °C to 435 °C, from 435 °C to 440 °C, from 440 °C to 445 °C, from 445 °C to 450 °C, from 450 °C to 455 °C, from 455 °C to 460 °C, from 460 °C to 465 °C, from 465 °C to 470 °C, from 470 °C to 475 °C, from 475 °C to 480 °C, from 480 °C to 485 °C, from 485 °C to 490 °C, from 490 °C to 495 °C, from 495 °C to 500 °C, from 505 °C to 510 °C, from 510 °C to 515 °C, from 515 °C to 520 °C, from 520 °C to 525 °C, from 525 °C to 530 °C, from 530 °C to 535 °C, from 535 °C to 540 °C, from 540 °C to 545 °C, from 545 °C to 550 °C, from 550 °C to 555 °C, from 555 °C to 460 °C, from 560 °C to 465 °C, from 565 °C to 570 °C, or from 570 °C to 575 °C. It will be appreciated that the peak temperature used may be different for different aluminum alloys.

[0085] The aluminum alloy product may optionally be subjected to a solution heat treatment process 235, where the temperature of the aluminum alloy product is increased to a temperature above a threshold temperature, such as a temperature at which precipitated components in the aluminum alloy product dissolve into a solid solution, and held above the threshold temperature for a period of time. At the end of the solution heat treatment process 235, the aluminum alloy product may be subjected to a quenching process 240, where dissolved components are fixed into place by rapidly reducing the temperature of the aluminum alloy by a quenching process. Such a quenching process 240 may involve exposing the aluminum alloy product to a solution, such as a quench solution including water, an aqueous solution, or a gas solution. In some examples, the rapid annealing and quenching process 225 may allow for a hold time during solution heat treatment process 235 to be reduced compared to solution heat treatment of an aluminum alloy product that is not subjected to rapid annealing and quenching process 225.

[0086] In embodiments, the processes overviewed in FIG. 2 may be performed discretely or as part of one or more continuous processing lines where the aluminum alloy product may be transported as a coil, a film, or a web of material between processing stages. The aluminum alloy product may be transported between stages by rolling the aluminum alloy product, which may be under tension, over or between one or more rollers, or by transporting the aluminum alloy product on one or more conveyors, for example. In addition, other stages not explicitly identified may be included before, between, and/or after any stage identified in FIG. 2. Other example stages include, but are not limited to, a washing stage, a chemical treatment stage, or a finishing stage. As an example, a finishing stage may correspond to a surface anodizing stage, a powder coating stage, a painting stage, a printing stage, and the like. Other example stages include cutting, blanking, and forming processes. In some cases, the alloy product may be transported between stages by rolling the aluminum alloy product into a coil, transporting the coil to a subsequent processing stage, and uncoiling the aluminum alloy product for the subsequent processing.

[0087] FIG. 3 provides a schematic illustration of an example rapid annealing and quenching system 300 for treatment of an aluminum alloy product 305. Aluminum alloy product 305 can comprise any suitable aluminum alloy product, such as a hot-rolled aluminum alloy product or a cold-rolled aluminum alloy product. Aluminum alloy product 305 can comprise any aluminum alloy described herein, but particularly may comprise a 2xxx series aluminum alloy, a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy. Aluminum alloy product 305 can have any suitable thickness, such as a thickness of from 1 mm to 8 mm, or a thickness of from 0.5 mm to 5 mm. In some examples, aluminum alloy product has a thickness of from 1.0 mm to 1.1 mm, from 1.1 mm to 1.2 mm, from 1.2 mm to 1.3 mm, from 1.3 mm to 1.4 mm, from 1.4 mm to 1.5 mm, from

1.5 mm to 1.6 mm, from 1.6 mm to 1.7 mm, from 1.7 mm to 1.8 mm, from 1.8 mm to 1.9 mm, from 1.9 mm to 2.0 mm, 2.0 mm to 2.1 mm, from 2.1 mm to 2.2 mm, from 2.2 mm to

2.3 mm, from 2.3 mm to 2.4 mm, from 2.4 mm to 2.5 mm, from 2.5 mm to 2.6 mm, from 2.6 mm to 2.7 mm, from 2.7 mm to 2.8 mm, from 2.8 mm to 2.9 mm, from 2.9 mm to 3.0 mm, 3.0 mm to 3.1 mm, from 3.1 mm to 3.2 mm, from 3.2 mm to 3.3 mm, from 3.3 mm to 3.4 mm, from 3.4 mm to 3.5 mm, from 3.5 mm to 3.6 mm, from 3.6 mm to 3.7 mm, from 3.7 mm to 3.8 mm, from 3.8 mm to 3.9 mm, from 3.9 mm to 4.0 mm, 4.0 mm to 4.1 mm, from 4.1 mm to 4.2 mm, from 4.2 mm to 4.3 mm, from 4.3 mm to 4.4 mm, from 4.4 mm to 4.5 mm, from 4.5 mm to 4.6 mm, from 4.6 mm to 4.7 mm, from 4.7 mm to 4.8 mm, from 4.8 mm to 4.9 mm, from 4.9 mm to 5.0 mm, 5.0 mm to 5.1 mm, from 5.1 mm to 5.2 mm, from 5.2 mm to 5.3 mm, from 5.3 mm to 5.4 mm, from 5.4 mm to 5.5 mm, from 5.5 mm to 5.6 mm, from

5.6 mm to 5.7 mm, from 5.7 mm to 5.8 mm, from 5.8 mm to 5.9 mm, from 5.9 mm to 6.0 mm, 6.0 mm to 6.1 mm, from 6.1 mm to 6.2 mm, from 6.2 mm to 6.3 mm, from 6.3 mm to

6.4 mm, from 6.4 mm to 6.5 mm, from 6.5 mm to 6.6 mm, from 6.6 mm to 6.7 mm, from 6.7 mm to 6.8 mm, from 6.8 mm to 6.9 mm, from 6.9 mm to 7.0 mm, 7.0 mm to 7.1 mm, from 7.1 mm to 7.2 mm, from 7.2 mm to 7.3 mm, from 7.3 mm to 7.4 mm, from 7.4 mm to 7.5 mm, from 7.5 mm to 7.6 mm, from 7.6 mm to 7.7 mm, from 7.7 mm to 7.8 mm, from 7.8 mm to 7.9 mm, or from 7.9 mm to 8.0 mm.

[0088] Rapid annealing and quenching system 300 can comprise individual annealing system 310 and quenching system 315, or the annealing and quenching systems can be combined. Rapid annealing system 310 can comprise any suitable annealing system which can increase the temperature of the aluminum alloy product to a peak temperature at rapid rates, such as at rates of up to about 100 °C/s. Example heating rates that are useful for a rapid annealing system include from 1 °C/s to 5 °C/s, from 5 °C/s to 10 °C/s, from 10 °C/s to 15 °C/s, from 15 °C/s to 20 °C/s, from 20 °C/s to 25 °C/s, from 25 °C/s to 30 °C/s, from 30 °C/s to 35 °C/s, from 35 °C/s to 40 °C/s, from 40 °C/s to 45 °C/s, from 45 °C/s to 50 °C/s, from 50 °C/s to 55 °C/s, from 55 °C/s to 60 °C/s, from 60 °C/s to 65 °C/s, from 65 °C/s to 70 °C/s, from 70 °C/s to 75 °C/s, from 75 °C/s to 80 °C/s, from 80 °C/s to 85 °C/s, from 85 °C/s to 90 °C/s, from 90 °C/s to 95 °C/s, or from 95 °C/s to 100 °C/s. In some cases, heating rates above 100 °C/s can be used. In one example, rapid annealing system 310 can comprise a series of permanent magnetic rotors 320 that are used to heat the aluminum alloy product 305 by way of magnetic induction heating. Permanent magnetic rotors 320 may be provided in any suitable arrangement of individual permanent magnetic rotors 320 or pairs of permanent magnetic rotors 320. Further details of an exemplary magnetic rotor-based magnetic induction heating system are described in U.S. Patent Application Publication No. 2018/0091263, which is hereby incorporated by reference in its entirety.

[0089] Quenching system 315 can comprise any suitable quenching system which can decrease the temperature of the aluminum alloy product at rapid rates, such as at rates of from about -500 °C/s to about -2 °C/s. Example cooling rates that are useful for a quenching system include from -2 °C/s to -5 °C/s, from -5 °C/s to -10 °C/s, from -10 °C/s to -15 °C/s, from -15 °C/s to -20 °C/s, from -20 °C/s to -25 °C/s, from -25 °C/s to -30 °C/s, from -30 °C/s to -35 °C/s, from -35 °C/s to -40 °C/s, from -40 °C/s to -45 °C/s, from -45 °C/s to -50 °C/s, from -50 °C/s to -55 °C/s, from -55 °C/s to -60 °C/s, from -60 °C/s to -65 °C/s, from -65 °C/s to -70 °C/s, from -70 °C/s to -75 °C/s, from -75 °C/s to -80 °C/s, from -80 °C/s to -85 °C/s, from -85 °C/s to -90 °C/s, from -90 °C/s to -95 °C/s, from -95 °C/s to -100 °C/s, from -100 °C/s to -125 °C/s, from -125 °C/s to -150 °C/s, from -150 °C/s to -175 °C/s, from -175 °C/s to -200 °C/s, from -200 °C/s to -225 °C/s, from -225 °C/s to -250 °C/s, from -150 °C/s to -275 °C/s, from -275 °C/s to -300 °C/s, from -300 °C/s to -325 °C/s, from -325 °C/s to -350 °C/s, from -350 °C/s to -375 °C/s, from -375 °C/s to -400 °C/s, from -400 °C/s to -425 °C/s, from - 425 °C/s to -450 °C/s, from -450 °C/s to -475 °C/s, or from -475 °C/s to -500 °C/s. In some cases, cooling rates below -500 °C/s can be used. As used herein, a cooling rate of -5 °C/s refers to the temperature of an aluminum alloy product being decreased by 5 °C in one second. In one example, quenching system 315 can comprise a series of spray nozzles 325 that are used to apply a quenching fluid to the aluminum alloy product 305. Example quenching fluids can comprise a gas, air, water, an aqueous solution, oil, or other suitable quenching fluids.

[0090] Optionally, a hold region can be positioned between rapid annealing system 310 and quenching system 315. The hold region can comprise any suitable region that maintains the temperature of the aluminum alloy product 305 at or close to the peak temperature achieved in the rapid annealing system 310, such as within 20 °C of the peak temperature. The hold region may maintain the temperature of the aluminum alloy product 305 at or close to the peak temperature for up to 1 minute, for example. Example hold times include from 0 seconds to 5 seconds, from 5 seconds to 10 seconds, from 10 seconds to 15 seconds, from 15 seconds to 20 seconds, from 20 seconds to 25 seconds, from 25 seconds to 30 seconds, from 30 seconds to 35 seconds, from 35 seconds to 40 seconds, from 40 seconds to 45 seconds, from 45 seconds to 50 seconds, from 50 seconds to 55 seconds, or from 55 seconds to 1 minute. Hold times in excess of 1 minute may be applied in some cases.

[0091] In some examples, rapid heating and quenching system 300 can be used to anneal and quench aluminum alloy product 305 very quickly, such as in 5 minutes or less. For example, a portion of the aluminum alloy product 305 can enter the rapid annealing system 310, exit the rapid annealing system 310, enter the quenching system 315, and exit the quenching system 315 in 5 minutes or less. In some cases, any portion of the aluminum alloy product is subjected to temperatures greater than or about 100 °C during rapid annealing and quenching for at most 5 minutes. In some examples, these times can be from 5 seconds to 5 minutes, such as from 15 seconds to 30 seconds, from 30 seconds to 45 seconds, from 45 seconds to 1 minute, from 1 minute to 1.25 minutes, from 1.25 minutes to 1.5 minutes, from 1.5 minutes to 1.75 minutes, from 1.75 minutes to 2 minutes, from 2 minutes to 2.25 minutes, from 2.25 minutes to 2.5 minutes, from 2.5 minutes to 2.75 minutes, from 2.75 minutes to 3 minutes, from 3 minutes to 3.25 minutes, from 3.25 minutes to 3.5 minutes, from 3.5 minutes to 3.75 minutes, from 3.75 minutes to 4 minutes, from 4 minutes to 4.25 minutes, from 4.25 minutes to 4.5 minutes, from 4.5 minutes to 4.75 minutes, or from 4.75 minutes to 5 minutes. The total length of time for processing all of the aluminum alloy product 305 may depend on the rate at which the aluminum alloy product 305 passes through the rapid annealing and quenching system 300 and the length of the aluminum alloy product. In some examples, the aluminum alloy product 305 may pass through the rapid annealing and/or quenching system 300 at rates of from 5 m/min to 600 m/min, such as from 10 m/min to 20 m/min, from 20 m/min, to 30 m/min, from 30 m/min to 40 m/min, from 40 m/min to 50 m/min, from 50 m/min to 60 m/min, from 60 m/min to 70 m/min, from 70 m/min to 80 m/min, from 80 m/min to 90 m/min, from 90 m/min to 100 m/min, from 100 m/min to 110 m/min, from 110 m/min to 120 m/min, from 120 m/min, to 130 m/min, from 130 m/min to 140 m/min, from 140 m/min to 150 m/min, from 150 m/min to 160 m/min, from 160 m/min to 170 m/min, from 170 m/min to 180 m/min, from 180 m/min to 190 m/min, from 190 m/min to 200 m/min, from 200 m/min to 210 m/min, from 210 m/min to 220 m/min, from 220 m/min to 230 m/min, from 230 m/min to 240 m/min, from 240 m/min to 250 m/min, from 250 m/min to 260 m/min, from 260 m/min to 270 m/min, from 270 m/min to 280 m/min, from 280 m/min to 290 m/min, from 290 m/min to 300 m/min, from 300 m/min to 310 m/min, from 310 m/min to 320 m/min, from 320 m/min to 330 m/min, from 330 m/min to 340 m/min, from 340 m/min to 350 m/min, from 350 m/min to 360 m/min, from 360 m/min to 370 m/min, from 370 m/min to 380 m/min, from 380 m/min to 390 m/min, from 390 m/min to 400 m/min, from 400 m/min to 410 m/min, from 410 m/min to 420 m/min, from 420 m/min to 430 m/min, from 430 m/min to 440 m/min, from 440 m/min to 450 m/min, from 450 m/min to 460 m/min, from 460 m/min to 470 m/min, from 470 m/min to 480 m/min, from 480 m/min to 490 m/min, from 490 m/min to 500 m/min, from 500 m/min to 510 m/min, from 510 m/min to 520 m/min, from 520 m/min to 530 m/min, from 530 m/min to 540 m/min, from 540 m/min to 550 m/min, from 550 m/min to 560 m/min, from 560 m/min to 570 m/min, from 570 m/min to 580 m/min, from 580 m/min to 590 m/min, from 590 m/min to 600 m/min. In some examples, an entire coil of aluminum alloy product 305 can be subjected to annealing and quenching by rapid annealing and quenching system 300 in 30 minutes or less, 1 hour or less, or 2 hours or less, including the processes of uncoiling the aluminum alloy product 305, passing the aluminum alloy product 305 through rapid annealing and quenching system 300, and recoiling the aluminum alloy product 305.

[0092] The rapid heating and quenching system 300 can have any suitable heating power and line capacity. In some cases, the line capacity may be a function of the heating power, incoming temperature for aluminum alloy product 305, and peak temperature to raise the aluminum alloy product 305 to. In some examples, rapid heating and quenching system 300 can have a heating power of from 1 MW to 10 MW, or more. Example powers include, but are not limited to, 1 MW, 1.5 MW, 2 MW, 2.5 MW, 3 MW, 3.5 MW, 4 MW, 4.5 MW, 5 MW, 5.5 MW, 6 MW, 6.5 MW, 7 MW, 7.5 MW, 8 MW, 8.5 MW, 9 MW, 9.5 MW, or 10 MW. Powers may be more or less or in between any of these values. The temperature of the aluminum alloy product 305 prior to or at entry into the rapid heating and quenching system 300 can be any suitable temperature, such as from about 25 °C to about 400 °C, such as from 25 °C to 50 °C, from 50 °C to 75 °C, from 75 °C to 100 °C, from 100 °C to 125 °C, from 125 °C to 150 °C, from 150 °C to 175 °C, from 175 °C to 200 °C, from 200 °C to 225 °C, from 225 °C to 250 °C, from 250 °C to 275 °C, from 275 °C to 300 °C, from 300 °C to 325 °C, from 325 °C to 350 °C, from 350 °C to 375 °C, or from 375 °C to 400 °C. The line capacity of rapid heating and quenching system may range from about 40 kTa to about 400 kTa, such as from 40 kTa to 50 kTa, from 50 kTa to 75 kTa, from 75 kTa to 100 kTa, from 100 kTa to 125 kTa, from 125 kTa to 150 kTa, from 150 kTa to 175 kTa, from 175 kTa to 200 kTa, from 200 kTa to 225 kTa, from 225 kTa to 250 kTa, from 250 kTa to 275 kTa, from 275 kTa to 300 kTa, from 300 kTa to 325 kTa, from 325 kTa to 350 kTa, from 350 kTa to 375 kTa, or from 375 kTa to 400 kTa. Line capacity may be higher still, such as if heating power is in excess of 7.5 MW or 10 MW.

[0093] In some examples, uncoiling may not be used immediately before rapid annealing. For example, in some cases, the rapid annealing and quenching system 300 may be placed downstream from a cold rolling process to allow the aluminum alloy product 305 to be rapidly annealed and quenched directly following a cold rolling pass where the aluminum alloy product 305 has already been uncoiled. In some examples, recoiling may not be used immediately after quenching. For example, in some cases, the rapid annealing and quenching system 300 may be placed upstream from a cold rolling process to allow the aluminum alloy product 305 to be cold rolled directly following rapid annealing and quenching.

[0094] The aluminum alloy product subjected to rapid annealing and quenching can comprise any suitable alloy and have any suitable dimensions. For example, the alloy product can have a thickness of from 1 mm to 8 mm. In some examples, the aluminum alloy product can comprise a 6xxx series aluminum alloy, a 7xxx series aluminum alloy, a 2xxx series aluminum alloy, or a 5xxx series aluminum alloy.

[0095] The examples disclosed herein will serve to further illustrate aspects of the invention without, at the same time, however, constituting any limitation thereof. On the contrary, it is to be clearly understood that resort may be had to various embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to those skilled in the art without departing from the spirit of the invention. The examples and embodiments described herein may also make use of conventional procedures, unless otherwise stated. Some of the procedures are described herein for illustrative purposes.

EXAMPLE 1

[0096] A series of tests were performed to evaluate the properties of rolled aluminum alloy products subjected to rapid annealing and quenching as described herein. Initial tests were performed using a Gleeble thermomechanical simulator to evaluate mechanical properties, degree of recrystallization, and precipitate coarsening as a function of annealing temperature and quenching rate and aid in defining processing conditions for subsequent tests. Coupons of a hot-rolled 6xxx series aluminum alloy with 5 mm thickness were heated to peak temperatures from 325 °C to 500 °C using rapid heating (about 10-20 °C/s) and subjected to immediate air quenching upon reaching the peak temperature, air quenching 10 seconds after reaching the peak temperature, or non-quenched cooling with a temperature profile similar to coil cooling. The air quenching rate was about -40 °C/s.

[0097] Beginning at temperatures of 450 °C, full or nearly full recrystallization was observed for all samples. The air quenched samples did not exhibit significant recrystallization at peak temperatures of 400 °C or less. For the samples subjected to a cooling profile similar to coil cooling, significant recrystallization (about 80%) and full recrystallization were observed for peak temperatures of 350 °C and 400 °C, respectively. [0098] For the samples subjected to a cooling profile similar to coil cooling, small amounts of precipitate coarsening were observed for peak temperatures of 400 °C, and more and considerable coarsening was observed at peak temperatures of 450 °C and 500 °C. For the samples with immediate air quenching, no precipitate coarsening was observed for any peak temperature. For the samples with 10 second delayed air quenching, no precipitate coarsening was observed for any peak temperature except for the sample subjected to a peak temperature of 500 °C, where some coarsening was observed.

[0099] FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, and FIG. 4E provides optical micrographs comparing the grain structure of samples of a 6xxx series aluminum alloy product subjected to rapid heating to different peak temperatures followed immediately by air quenching, samples of a 6xxx series aluminum alloy product subjected to rapid heating to different peak temperatures followed by air quenching after 10 seconds, and samples subjected to batch annealing for 2 hours followed by coil type cooling in the batch annealing furnace. The samples subjected to rapid heating to 500 °C show full recrystallization and smaller and more equiaxed grains than the comparable product subjected to batch annealing.

[0100] FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D, and FIG. 5E provide optical micrographs comparing the precipitates of samples of a 6xxx series aluminum alloy product subjected to rapid heating to different peak temperatures followed immediately by air quenching, samples of a 6xxx series aluminum alloy product subjected to rapid heating to different peak temperatures followed by air quenching after 10 seconds, and samples subjected to batch annealing for 2 hours followed by coil type cooling in the batch annealing furnace. The samples subjected to rapid heating and air quenching generally show less particle coarsening than the samples subjected to slower coil type quenching in batch annealing.

[0101] Subsequent tests were conducted by passing samples of a 5 mm thick hot-rolled 6xxx series aluminum alloy sheet panel through a rapid heating and quenching unit where magnetic induction heating was used to rapidly heat the samples to a peak metal temperature, followed by quenching using by exposure to cooling water. Heating rates of up to or about 20 °C/s were used and cooling rates of about -100 °C/s were used.

[0102] FIG. 6 provides scanning electron micrograph images comparing cross sections of a sample processed using the Gleeble thermomechanical simulator (top) and a sample subjected to processing with the rapid heating and quenching unit (bottom). Both samples were subjected to rapid heating at a rate of about 20 °C/s to a peak temperature of 460 °C, and the microstructures were nearly indistinguishable.

[0103] Subsequent tests were conducted where two coils of a 5 mm thick hot-rolled 6xxx series aluminum alloy sheet were uncoiled and passed through a rapid heating and quenching unit where magnetic induction heating was used to rapidly anneal the samples at a peak metal temperature, followed by quenching by exposure to cooling water. Heating rates of up to or about 20 °C/s were used and cooling rates of about -100 °C/s were used. A first coil was processed using a peak temperature of 460 °C and a second coil was processed using a peak temperature of 490 °C. Samples were subjected to cold rolling following the rapid annealing and quenching, where the thickness was reduced from 5 mm to 0.9 mm. Samples were subjected to a continuous annealing and solution heat treatment following the cold rolling, where the samples were heated to 540 °C and held for 8 seconds followed by air quenching. A comparison sample was subjected to batch annealing and coil cooling, for reference. Samples were subjected to mechanical testing at various points of the processing.

[0104] FIG. 7 provides data showing yield stress of the samples subjected to rapid annealing and water quenching as well as a sample subjected to batch annealing (all prior to cold rolling). FIG. 8 provides data showing total elongation of the samples subjected to rapid annealing and water quenching as well as a sample subjected to batch annealing (all prior to cold rolling). The measured values shown in these figures corresponds to properties averaged across the transverse width of the sample. The samples subjected to rapid annealing and quenching exhibited higher yield strength and lower elongation compared to the batch annealed samples.

[0105] FIG. 9 shows optical micrographs of a cross section of the samples subjected to rapid annealing and water quenching as well as a sample subjected to batch annealing (all prior to cold rolling). The samples subjected to rapid annealing and quenching exhibited a more uniform and finer grain structure compared to the batch annealed samples.

[0106] FIG. 10 provides 50 pm wide micrograph images of a sample subjected to rapid annealing at 490 °C and water quenching and a sample subjected to batch annealing (both prior to cold rolling) to show the amount and size of Mg2Si precipitates (dark spots in images). The sample subjected to rapid annealing and quenching showed finer precipitates, indicating higher strength and formability could be expected. Due to the presence of less coarse precipitates, the sample subjected to rapid annealing and quenching does not need as long a duration for a subsequent solution heat treatment process to dissolve the precipitates as the batch annealed sample.

[0107] The mechanical properties of the samples (rapid annealing at 460 °C and water quenching, RH+Q 460 °C; rapid annealing at 490 °C and water quenching, RH+Q 490 °C; and batch annealing, BA) were evaluated after cold rolling, solution heat treatment, and aging. FIG. 11 compares the yield stress for the samples after room temperature aging (T4 temper condition) and artificial aging/paint baking (T81 temper condition). FIG. 12 compares the total elongation for the samples after room temperature aging (T4 temper condition). The strength and elongation properties for the samples at each condition are comparable.

[0108] Subsequent tests were conducted where coils of a hot-rolled 6xxx series aluminum alloy sheet were uncoiled and passed through a rapid heating and quenching unit, where the metal was rapidly heated to at rates of 5 °C/s, 10 °C/s, 20 °C/s , 40 °C/s, or 100 °C/s to a peak metal temperature of 460 °C, 480 °C, 490 °C, or 530 °C, followed by quenching by exposure to cooling water. Samples were subjected to cold rolling after the rapid annealing and quenching. Samples were subjected to a continuous annealing and solution heat treatment after the cold rolling. Samples were subjected to testing at various points of the processing. [0109] For example, samples were subjected to conductivity testing to evaluate the relative amounts of dissolved solute (alloying elements) in the aluminum matrix. Results of the conductivity testing are shown in FIG. 13. For samples annealed to a peak temperature of 460 °C, the conductivity measurements are generally consistent, though at a heating rate of 100 °C/s, the conductivity drops. For samples annealed to a peak temperature of 530 °C, the lowest conductivity was observed at heating rates of 5 °C/s and 10 °C/s, indicating these samples had the most amount of solute dissolved in the aluminum matrix, while fine particles still remain undissolved in the sample processed at a heating rate of 100 °C/s.

[0110] FIG. 14A shows micrographs illustrating the through thickness grain structure (transverse cross section, perpendicular to rolling direction) of samples annealed to a peak temperature of 460 °C, showing no significant impact of heating rate on grain size. FIG. 14C shows micrographs illustrating the through thickness grain structure (transverse cross section, perpendicular to rolling direction) of samples annealed to a peak temperature of 530 °C, showing no significant impact of heating rate on grain size. [OHl] FIG. 15A and FIG. 15B provide micrograph images of samples subjected to rapid annealing to peak temperatures of 460 °C and 530 °C at different heating rates to show the amount and size of Mg2Si precipitates (dark spots in images). In general, the particle content appears to be similar at the different heating rates, though the higher peak temperature of 530 appears to reduce particle numbers.

[0112] FIG. 16 provides electrical conductivity data of samples subjected to rapid annealing to different peak temperatures, showing measured conductivity values at different positions in terms of % IACS (International Annealed Copper Standard). These values are significantly lower than those observed for batch annealed reference samples, which exhibited an electrical conductivity of about 56.8 % IACS.

[0113] FIG. 17 provides measured yield stress of samples subjected to rapid annealing to different peak temperatures. These values are significantly higher than those observed for batch annealed reference samples, which exhibited a yield strength of about 51-52 MPa.

[0114] FIG. 18 provides measured maximum axial strain of samples subjected to rapid annealing to different peak temperatures. These values are significantly lower than those observed for batch annealed reference samples, which exhibited a maximum axial strain of about 32-36 MPa.

ILLUSTRATIVE ASPECTS

[0115] As used below, any reference to a series of aspects (e.g., “Aspects 1-4”) or nonenumerated group of aspects (e.g., “any previous or subsequent aspect”) is to be understood as a reference to each of those aspects disjunctively (e.g., “Aspects 1-4” is to be understood as “Aspects 1, 2, 3, or 4 ”).

[0116] Aspect 1 is a method comprising: providing a rolled aluminum alloy product; subjecting the rolled aluminum alloy product to a rapid annealing process to produce an annealed aluminum alloy product, wherein the rapid annealing process comprises heating the rolled aluminum alloy product at a rate of up to 100 °C/s to a peak temperature of from 400 °C to 575 °C; and subjecting the annealed aluminum alloy product to a quenching process to produce a quenched aluminum alloy product, wherein the quenching process comprises cooling portions of the annealed aluminum alloy product at a rate of from -500 °C/s to -2 °C/s.

[0117] Aspect 2 is the method of any previous or subsequent aspect, further comprising: subjecting the quenched aluminum alloy product to a cold rolling process to produce a cold- rolled aluminum alloy product. [0118] Aspect 3 is the method of any previous or subsequent aspect, further comprising: subjecting the quenched aluminum alloy product to a solution heat-treatment process.

[0119] Aspect 4 is the method of any previous or subsequent aspect, further comprising: subjecting the quenched aluminum alloy product to one or more of a cutting process, a forming process, an ageing process.

[0120] Aspect 5 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product is a hot-rolled aluminum alloy product.

[0121] Aspect 6 is the method of any previous or subsequent aspect, wherein the quenched aluminum alloy product exhibits an average Mg2Si particle size of less than 2 pm.

[0122] Aspect 7 is the method of any previous or subsequent aspect, wherein the quenched aluminum alloy product exhibits an electrical conductivity of from 40% IACS to 55% IACS.

[0123] Aspect 8 is the method of any previous or subsequent aspect, wherein the quenched aluminum alloy product exhibits a yield stress of from 70 MPa to 160 MPa.

[0124] Aspect 9 is the method of any previous or subsequent aspect, wherein the quenched aluminum alloy product exhibits a total elongation of from 20% to 30%.

[0125] Aspect 10 is the method of any previous or subsequent aspect, wherein the quenched aluminum alloy product exhibits an average grain size of 10 pm to 35 pm.

[0126] Aspect 11 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product has a thickness of from 1 mm to 8 mm.

[0127] Aspect 12 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product has a thickness of from 0.5 mm to 5 mm.

[0128] Aspect 13 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product is at least partially unrecrystallized or is fully unrecrystallized.

[0129] Aspect 14 is the method of any previous or subsequent aspect, wherein the annealed aluminum alloy product is at least partially recrystallized or is fully recrystallized.

[0130] Aspect 15 is the method of any previous or subsequent aspect, wherein the rapid annealing process comprises heating the rolled aluminum alloy product using one or more magnetic induction heating units.

[0131] Aspect 16 is the method of any previous or subsequent aspect, wherein the rapid annealing process or the quenching process comprises exposing the annealed aluminum alloy product to a quenching fluid.

[0132] Aspect 17 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product is a cold-rolled aluminum alloy product. [0133] Aspect 18 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product comprises a 6xxx series aluminum alloy or a 7xxx series aluminum alloy.

[0134] Aspect 19 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product comprises a 2xxx series aluminum alloy or a 5xxx series aluminum alloy.

[0135] Aspect 20 is the method of any previous or subsequent aspect, wherein the rapid annealing process does not comprise a batch or coil annealing process, wherein the rapid annealing process does not comprise a batch or coil cooling process, wherein subjecting the rolled aluminum alloy product to the rapid annealing process comprises uncoiling the rolled aluminum alloy product, or wherein the method further comprises coiling the quenched aluminum alloy product prior to a subsequent cold rolling process.

[0136] Aspect 21 is the method of any previous or subsequent aspect, wherein the rapid annealing process is a continuous heating process that heats only portions of the rolled aluminum alloy product at a time; or wherein the quenching process is a continuous cooling process that cools only portions of the annealed aluminum alloy product at a time.

[0137] Aspect 22 is the method of any previous or subsequent aspect, wherein the rapid annealing process comprises passing the rolled aluminum alloy product through a heating system at a rate of from 5 m/min to 600 m/min; or wherein the quenching process comprises passing the annealed aluminum alloy product through a quenching system at a rate of from 5 m/min to 600 m/min.

[0138] Aspect 23 is the method of any previous or subsequent aspect, wherein the rolled aluminum alloy product is subjected to temperatures greater than 100 °C during the rapid annealing and quenching processes for at most 5 minutes.

[0139] Aspect 24 is the method of any previous or subsequent aspect, further comprising holding the rolled aluminum alloy product within 20 °C of the peak temperature for up to 1 minute prior to the quenching process.

[0140] Aspect 25 is an aluminum alloy prepared using the method of any of any previous or subsequent aspect.

[0141] Aspect 26 is an aluminum alloy product comprising: a formed or stretched aluminum alloy sheet product comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy, wherein a surface arithmetical mean height (Sa) of the formed or stretched aluminum alloy sheet product is at most 10 pm, and wherein a thickness of the formed or stretched aluminum alloy sheet product is from 1.00 mm to 3.5 mm.

[0142] Aspect 27 is the aluminum alloy product of any previous or subsequent aspect, wherein the formed or stretched aluminum alloy sheet product comprises a 6xxx series aluminum alloy, and wherein the formed or stretched aluminum alloy sheet product is free or substantially free of surface roping bands.

[0143] Aspect 28 is the aluminum alloy product of any previous or subsequent aspect, wherein the formed or stretched aluminum alloy sheet product comprises a 5xxx series aluminum alloy, and wherein the formed or stretched aluminum alloy sheet product is free or substantially free of surface Luders bands.

[0144] Aspect 29 is the aluminum alloy product of any previous aspect, prepared using the method of any previous aspect.

[0145] All patents and publications cited herein are incorporated by reference in their entirety. The foregoing description of the embodiments, including illustrated embodiments, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or limiting to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art.

Claims

WHAT IS CLAIMED IS:

1. A method comprising: providing a rolled aluminum alloy product; subjecting the rolled aluminum alloy product to a rapid annealing process to produce an annealed aluminum alloy product, wherein the rapid annealing process comprises heating the rolled aluminum alloy product at a rate of up to 100 °C/s to a peak temperature of from 400 °C to 575 °C; and subjecting the annealed aluminum alloy product to a quenching process to produce a quenched aluminum alloy product, wherein the quenching process comprises cooling portions of the annealed aluminum alloy product at a rate of from -500 °C/s to -2 °C/s.

2. The method of claim 1, further comprising: subjecting the quenched aluminum alloy product to a cold rolling process to produce a cold-rolled aluminum alloy product.

3. The method of claim 1, further comprising: subjecting the quenched aluminum alloy product to a solution heat-treatment process.

4. The method of claim 1, further comprising: subjecting the quenched aluminum alloy product to one or more of a cutting process, a forming process, an ageing process.

5. The method of claim 1, wherein the rolled aluminum alloy product is a hot-rolled aluminum alloy product.

6. The method of claim 1, wherein the quenched aluminum alloy product exhibits an average Mg2Si particle size of less than 2 pm.

7. The method of claim 1, wherein the quenched aluminum alloy product exhibits an electrical conductivity of from 40% IACS to 55% IACS.

8. The method of claim 1, wherein the quenched aluminum alloy product exhibits a yield stress of from 70 MPa to 160 MPa.

9. The method of claim 1, wherein the quenched aluminum alloy product exhibits a total elongation of from 20% to 30%.

10. The method of claim 1, wherein the quenched aluminum alloy product exhibits an average grain size of 10 pm to 35 pm.

11. The method of claim 1, wherein the rolled aluminum alloy product has a thickness of from 1 mm to 8 mm.

12. The method of claim 1, wherein the rolled aluminum alloy product has a thickness of from 0.5 mm to 5 mm.

13. The method of claim 1, wherein the rolled aluminum alloy product is at least partially unrecrystallized or is fully unrecrystallized.

14. The method of claim 1, wherein the annealed aluminum alloy product is at least partially recrystallized or is fully recrystallized.

15. The method of claim 1, wherein the rapid annealing process comprises heating the rolled aluminum alloy product using one or more magnetic induction heating units.

16. The method of claim 1, wherein the quenching process comprises exposing the annealed aluminum alloy product to a quenching fluid.

17. The method of claim 1, wherein the rolled aluminum alloy product is a cold-rolled aluminum alloy product.

18. The method of claim 1, wherein the rolled aluminum alloy product comprises a 6xxx series aluminum alloy or a 7xxx series aluminum alloy.

19. The method of claim 1, wherein the rolled aluminum alloy product comprises a 2xxx series aluminum alloy or a 5xxx series aluminum alloy.

20. The method of claim 1, wherein the rapid annealing process does not comprise a batch or coil annealing process, wherein the rapid annealing process does not comprise a batch or coil cooling process, wherein subjecting the rolled aluminum alloy product to the rapid annealing process comprises uncoiling the rolled aluminum alloy product, or wherein the method further comprises coiling the quenched aluminum alloy product prior to a subsequent cold rolling process.

21. The method of claim 1, wherein the rapid annealing process is a continuous heating process that heats only portions of the rolled aluminum alloy product at a time; or wherein the quenching process is a continuous cooling process that cools only portions of the annealed aluminum alloy product at a time.

22. The method of claim 1, wherein the rapid annealing process comprises passing the rolled aluminum alloy product through a heating system at a rate of from 5 m/min to 600 m/min; or wherein the quenching process comprises passing the annealed aluminum alloy product through a quenching system at a rate of from 5 m/min to 600 m/min.

23. The method of claim 1, wherein the rolled aluminum alloy product is subjected to temperatures greater than 100 °C during the rapid annealing and quenching processes for at most 5 minutes.

24. The method of claim 1, further comprising holding the rolled aluminum alloy product within 20 °C of the peak temperature for up to 1 minute prior to the quenching process.

25. An aluminum alloy prepared using the method of any of claims 1-24.

26. An aluminum alloy product comprising: a formed or stretched aluminum alloy sheet product comprising a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy, wherein a surface arithmetical mean height (Sa) of the formed or stretched aluminum alloy sheet product is at most 10 pm, and wherein a thickness of the formed or stretched aluminum alloy sheet product is from 1.00 mm to 3.5 mm.

27. The aluminum alloy product of claim 26, wherein the formed or stretched aluminum alloy sheet product comprises a 6xxx series aluminum alloy, and wherein the formed or stretched aluminum alloy sheet product is free or substantially free of surface roping bands.

28. The aluminum alloy product of claim 26, wherein the formed or stretched aluminum alloy sheet product comprises a 5xxx series aluminum alloy, and wherein the formed or stretched aluminum alloy sheet product is free or substantially free of surface Luders bands.

29. The aluminum alloy product of any of claims 26-28, prepared using the method of any of claims 1-24.