KR20240058902A - Aluminum alloy article with low roping and method of making the same - Google Patents

Abstract

Aluminum alloys with low roping are provided herein. A method for making an aluminum alloy with low roff, which may include annealing heat treatment of the unrecrystallized aluminum product at a predetermined temperature of less than or equal to 495° C. for a time of less than or equal to 25 minutes to produce a recrystallized aluminum product. Also provided herein.

Description

Aluminum alloy article with low roping and method of making the same

Cross-reference to related applications

This application claims the benefit and priority of U.S. Provisional Application No. 63/261,042, filed September 9, 2021, which is incorporated herein by reference in its entirety.

The present disclosure relates generally to metallurgy, and more specifically to aluminum alloys and aluminum alloy products with low roping. Additionally, the present disclosure also provides methods for making aluminum alloy products, including those with low ropes.

Aluminum articles are desirable for use in many different applications, especially applications where strength and durability are desired. For example, aluminum alloys are commonly used instead of steel in automotive skin panels and structural applications. Aluminum alloys are typically about 2.8 times less dense than steel, so using these materials can reduce a vehicle's weight and significantly improve fuel efficiency. Nevertheless, there are several challenges to using currently available aluminum alloys in automotive and other applications.

One of the challenges of these skin applications involves forming automotive components with high elongation and improved surface quality (e.g., low roping) for high bendability during assembly of automotive components. Improvements in surface quality and bendability can be achieved through continuous inter-annealing at high temperatures (e.g., greater than 540° C.), or through prolonged inter-batch annealing at lower temperatures (e.g., 2 hours). .

Roping is a deformation-induced roughness or macroscopic surface roughness defect. Roping can be characterized by visible lines several centimeters wide along the rolling direction. Roping can occur due to material stretching transversely. The surface distribution of ridges and valleys can limit the material's use in exterior panels in automotive applications.

The term examples and similar terms are intended to broadly refer to all subject matter of this disclosure and the claims below. Statements containing these terms should not be construed as limiting the subject matter described herein or limiting the meaning or scope of the claims below. Embodiments of the disclosure covered herein are defined by the claims below and not by 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 separately for determining the scope of the claimed subject matter. The subject matter should be understood by reference to the entire specification, some or all drawings, and each claim, as appropriate, of this disclosure.

In a first aspect, a method of making a dual recrystallized aluminum product is disclosed. Dual recrystallized aluminum products can have bending and elongation properties that allow for superior performance in use. Dual recrystallized aluminum products may also or alternatively exhibit no roping or low roping characteristics.

An example method may include providing an unrecrystallized aluminum product and subjecting the non-recrystallized aluminum product to an intermediate annealing heat treatment. The intermediate annealing heat treatment may be performed at a predetermined temperature of up to 400° C. for a time of up to 25 minutes to produce the first recrystallized aluminum product.

In some cases, the first recrystallized aluminum product may be processed to achieve desired properties after the first recrystallization. For example, the first recrystallized aluminum product can be processed such as cold rolling to produce a rolled product. The treatment can achieve cold reductions of 40% to 99%. Additional processing may include performing a solution heat treatment on the first recrystallized aluminum product to produce a double recrystallized aluminum product.

Double recrystallized aluminum products can exhibit specific properties to achieve desired performance. For example, a double recrystallized aluminum product may optionally exhibit an f10% bend value of up to 0.55 in the transverse direction or an f15% bend value of up to 0.70 in the transverse direction. Double recrystallized aluminum products may additionally or alternatively exhibit a uniform elongation of at least 21% or a surface arithmetic average height (Sa) of at most 0.50 μm. Other examples of properties of double recrystallized aluminum products include optionally an average undissolved precipitate size of 0.05 μm to 0.5 μm, the undissolved precipitates occupying an area fraction of 0% to 1%, and microvoids. has a conductivity of 25 mΩ/m to 40 mΩ/m and/or an area fraction of 0% to 0.3%.

In some cases, certain properties are achieved by or at least partially as a result of the intermediate annealing heat treatment. Optionally, the predetermined temperature of the intermediate annealing heat treatment may be at most 350° C., and the time of the intermediate annealing heat treatment may be at most 10 minutes or at most 5 minutes. The intermediate annealing heat treatment may include passing the unrecrystallized product through a furnace, such as a gas fired furnace, at a rate of 5 m/min to 200 m/min. In other cases, the intermediate annealing heat treatment may include heating the unrecrystallized aluminum product using magnetic heating or electrical induction processes.

Optionally, the unrecrystallized aluminum product includes a 6xxx series aluminum alloy or a 1xxx, 2xxx, 3xxx, 4xxx, 5xxx, 7xxx or 8xxx series aluminum alloy. In some embodiments, the thickness of the unrecrystallized aluminum product is between 0.1 mm and 5.0 mm as before the intermediate annealing heat treatment. Unrecrystallized aluminum products may include hot rolled aluminum products and/or cold rolled or partially cold rolled aluminum products. Cold rolled aluminum products can have cold reductions of 5% to 99%.

Other objects and advantages will become apparent from the following detailed description of non-limiting examples.

This specification refers to the following attached drawings, and use of the same reference numerals in different drawings is intended to illustrate similar or similar components.
1 provides a schematic diagram of an exemplary method of manufacturing a dual recrystallized aluminum alloy product.
Figure 2 provides a schematic diagram of the process for manufacturing aluminum alloy products.
Figure 3 provides a schematic diagram of an exemplary method of making recrystallized aluminum products.
Figures 4A and 4B provide schematic drawings of unrecrystallized and recrystallized aluminum alloy products.
FIGS. 5A, 5B, 5C, 5D, 5E, and 5F provide graphs comparing the strength properties of aluminum alloys prepared according to certain aspects of the present disclosure.
FIGS. 6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6H provide graphs comparing elongation properties of aluminum alloys prepared according to certain aspects of the present disclosure.
7A, 7B, 7C, 7D, 7E, 7F, and 7G provide graphs comparing bending, Lankford ratio, and surface properties of aluminum alloys prepared according to certain aspects of the present disclosure.
Figure 8 provides a graph of surface properties of an aluminum alloy prepared according to certain aspects of the present disclosure.
9A, 9B, and 9C provide images of aluminum alloys made according to certain aspects of the present disclosure.
10A and 10B provide additional images of aluminum alloys made according to certain aspects of the present disclosure.
11A and 11B provide graphs comparing the deposit properties and conductivity of aluminum alloys prepared according to certain aspects of the present disclosure.
Figure 12 provides a microscopic image of an aluminum alloy prepared according to certain aspects of the present disclosure.
13A and 13B provide graphs comparing statistics from the microstructure of aluminum alloys prepared according to certain aspects of the present disclosure.
Figure 14 provides another graph comparing statistics from the microstructure of aluminum alloys prepared according to certain aspects of the present disclosure.

Described herein are aluminum alloy articles and methods that exhibit novel combinations of bending properties, elongation properties, microstructure, and methods of making such articles. These articles can be manufactured using high-speed, low-temperature intermediate annealing heat treatments. The resulting roping, bending and elongation properties may, in some cases, be similar to those produced by high-speed, high-temperature annealing or low-speed, low-temperature annealing processes.

Definitions and Explanations:

As used herein, the terms “invention,” “the invention,” “this invention,” and “the present invention” are intended to refer broadly to both the subject matter of this patent application and the claims that follow. It should be understood that phrases containing these terms do not limit the technical subject matter described herein and do not limit the meaning or scope of the claims below.

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

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

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

As used herein, sheet generally refers to aluminum products having a thickness of less than about 4 mm. For example, the sheet can have a thickness of less than 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., less than about 0.2 mm).

In this application, reference may be made to alloy temper or state. For a description of the most commonly used alloy tempers, refer to "American National Standards (ANSI) H35 on Alloy and Temper Designation Systems." F condition or temper refers to the aluminum alloy as manufactured. O state or temper refers to the aluminum alloy after annealing. The Hxx state or temper, also referred to herein as H temper, refers to a non-heat treatable aluminum alloy after cold rolling with or without heat treatment (e.g., annealing). Suitable H tempers include HX1, HX2, HX3 HX4, HX5, HX6, HX7, HX8 or HX9 tempers. The T1 state or temper refers to an aluminum alloy that has been cooled from hot working and aged naturally (e.g., at room temperature). The T2 condition or temper refers to an aluminum alloy that has been cooled from hot working, cold worked, and naturally aged. The T3 condition or temper refers to an aluminum alloy that has been solution heat treated, cold worked, and naturally aged. The T4 state or temper refers to a solution heat treated, naturally aged aluminum alloy. The T5 condition or temper refers to an aluminum alloy that has been cooled from hot working and artificially aged (e.g., at an elevated temperature). The T6 condition or temper refers to an aluminum alloy that has been solution heat treated and artificially aged. The T7 condition or temper refers to an aluminum alloy that has been solution heat treated and artificially overaged. The T8x condition or temper refers to an aluminum alloy that has been solution heat treated, cold worked, and artificially aged. The T9 condition or temper refers to an aluminum alloy that has been solution heat treated, artificially aged, and cold worked. W state or temper refers to aluminum alloy after solution heat treatment.

As used herein, terms such as “cast metal product,” “cast product,” “cast aluminum alloy product,” etc. are interchangeable and refer to direct cool casting (including direct cool co-casting) or semi-continuous casting, continuous casting, etc. Refers to products manufactured by casting (e.g., including the use of twin belt casters, twin roll casters, block casters, or any other continuous casters), electromagnetic casting, hot top casting, or any other casting method. .

As used herein, “room temperature” means 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 ℃, about 23 ℃, about 24 ℃, about 25 ℃, about 26 ℃, about 27 ℃, about 28 ℃, about 29 ℃, or about 30 ℃. As used herein, the meaning of “atmospheric conditions” may include approximately room temperature, relative humidity of about 20% to about 100%, and atmospheric pressure of about 975 millibars (mbar) to about 1050 mbar. For example, the relative humidity is 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 It may be 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%, or any value in between. For example, atmospheric pressure is 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, It may be about 1030 mbar, about 1035 mbar, about 1040 mbar, about 1045 mbar, about 1050 mbar, or any value in between.

All ranges disclosed herein should be understood to include any and all subranges subsumed therein. For example, a range stated as “1 to 10” should be considered to include any and all subranges between (inclusive of) the minimum value of 1 and the maximum value of 10; That is, it should be considered to include all subranges starting with a minimum value greater than or equal to 1, for example, from 1 to 6.1, and ending with a maximum value of 10 or less, for example, from 5.5 to 10. Unless otherwise specified, the expression "up to" when referring to the compositional amount of an ingredient means that the element is optional and includes 0% of the composition of that particular element. Unless otherwise stated, all composition ratios are in weight percent (wt%).

As used herein, the meanings of “a,” “an,” and “the” include singular and plural referents unless the context clearly dictates otherwise.

In the examples below, aluminum alloy products and their components are described by elemental composition in weight percent (% by weight). In each alloy, the balance is aluminum and the sum of all impurities is up to 0.15% by weight.

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

Unavoidable impurities, including materials or elements, may be present in the alloy in trace amounts due to the inherent properties of aluminum or leaching from contact with processing equipment. Some alloys as described may contain up to about 0.25% by weight of any element other than alloying elements, minor elements, and unavoidable impurities.

Manufacturing and preparation methods of alloy and aluminum alloy products

1 provides an overview of an exemplary method of manufacturing aluminum alloy products. The method of Figure 1 begins at 105 by casting aluminum alloy to form a cast aluminum alloy product, such as an ingot or other cast product. The alloys described herein may be cast using any suitable casting method known to those skilled in the art. As some non-limiting examples, the casting process may include a direct cooling (DC) casting process (110), a fusion casting process (115), or a continuous casting (CC) process (120). A continuous casting process may use a system that includes a pair of moving opposing casting surfaces (e.g., moving opposing belts, rolls, or blocks), a casting cavity between the pair of moving opposing casting surfaces, and a molten metal injector. . The molten metal injector may have an end opening through which molten metal can exit the molten metal injector and be injected into the casting cavity.

The clad layer may be attached to the core layer by any means known to those skilled in the art to form the cladded product. For example, the clad layer may be formed by direct cool co-casting (i.e., fusion casting 115), for example, as described in U.S. Pat. Nos. 7,748,434 and 8,927,113, both of which are incorporated by reference in their entirety; By hot and cold rolling the composite cast ingot as described in U.S. Pat. No. 7,472,740, which is incorporated herein by reference in its entirety; Alternatively, it may be attached to the core layer by roll bonding to achieve a metallurgical bond between the core and cladding. The initial and final dimensions of the clad aluminum alloy products described herein may be determined by the desired properties of the overall final product.

The cast aluminum alloy product is homogenized during the homogenization process 125 to form a homogenized aluminum alloy product. In the homogenization step, the cast product is heated to a temperature of about 400 °C to about 565 °C. For example, cast products are rated at 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. , may be heated to a temperature of about 510 °C, about 520 °C, about 530 °C, or about 540 °C up to 565 °C. The product may then be steeped (i.e. held at a specified temperature) for a period of time to form a homogenized product. In some examples, the total time of the homogenization step, including the heating and soaking steps, may be up to 72 hours. For example, the product may be heated and soaked to up to 500° C. for a total time of the homogenization step of up to 18 hours. Optionally, the product can be heated below 490° C. and soaked for a total of 18 hours during the homogenization step. In some cases, the homogenization step includes multiple processes. In some non-limiting examples, the homogenizing step includes heating the cast product to a first temperature for a first time and then to a second temperature for a second time. For example, a cast product may be heated to about 465° C. for about 3.5 hours and then to about 480° C. for about 6 hours. In some cases, the homogenization process 125 and casting process 105 are combined as casting with in situ homogenization.

The homogenized aluminum alloy product is rolled through one or more rolling joint passes (130) and/or one or more hot rolling passes (135), which may correspond to aluminum alloy articles such as aluminum alloy plates, aluminum alloy sheets or aluminum alloy sheets. Forms aluminum alloy products. The roll bonding process 130 may be performed in different ways. For example, the rolling bonding process 130 may include both hot rolling and cold rolling. Additionally, the roll bonding process 130 may be a one-step process or a multi-step process in which the material is metered during successive rolling steps. The individual rolling steps may optionally be separated by other processing steps including, for example, annealing steps, washing steps, heating steps, cooling steps, etc.

The homogenized product may be cooled to a temperature of 380° C. to 450° C. prior to starting hot rolling 135. For example, the homogenized product may be cooled to a temperature of 400°C to 425°C. The homogenized product can then be hot rolled at a temperature of 250° C. to 450° C. to form a hot rolled plate, the hot rolled sheet or hot rolled sheet having a gauge of 2 mm to 200 mm (e.g. 2 mm, 3 mm). 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 any value in between).

Alternatively, the cast product may be a continuously cast product capable of being cooled to a temperature of 300° C. to 450° C. For example, a continuously cast product may be cooled to a temperature of 325°C to 425°C or 350°C to 400°C. The continuously cast product is then hot rolled at a temperature of 300° C. to 450° C. so that the hot rolled sheet or hot rolled sheet has a gauge of 3 mm to 25 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, or any value in between).

Cast, homogenized or hot rolled products may be subjected to a disassembly process (140) or a disassembly and tandem process (145). Alternatively, the cold rolling process 150 may be used after the hot rolling process 135, the cracking process 140, or the cracking and tandem process 145. Cold rolling process 150 may use a cold rolling mill to cold roll aluminum products into thinner products, such as cold rolled sheets. The cold rolled product may have a gauge of about 0.1 to 7 mm, such as about 0.7 to 6.5 mm. Optionally, cold rolled products can be made in gauges 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. You can have Cold rolling (150) increases the gauge by up to 95% (e.g., up to 10%, up to 20%, up to 30%, up to 40%, up to 50%, up to 55%, up to 60%) compared to the gauge before cold rolling (150) begins. , up to 70%, up to 75%, up to 80%, or up to 85%, or up to 90%, up to 95%, or up to 99%).

After the cold rolling process 150, an intermediate annealing step 155 may be used. In some cases, the cold rolling process (150) is not used and the product after the hot rolling process (135), cracking process (140) and/or cracking/tandem process (145) undergoes an intermediate annealing step (155). The intermediate annealing step 155 may be any suitable treatment that produces a recrystallized aluminum product. The intermediate annealing step 155 may include heat treating the unrecrystallized aluminum product at a predetermined temperature of less than or equal to 495° C. for a time of less than or equal to 25 minutes to produce a recrystallized aluminum product. For example, a cast, homogenized, hot rolled or cold rolled product may be heated to a temperature of up to 495° C. for a period of up to 25 minutes as part of the intermediate annealing step 155. In some examples, the temperature is from about 300 °C to about 495 °C, such as 300 °C to 305 °C, 305 °C to 310 °C, 310 °C to 315 °C, 315 °C to 320 °C, 320 °C to 325 °C, 325 °C to 330 °C. , 330°C to 335°C, 335°C to 340°C, 340°C to 345°C, 345°C to 350°C, 350°C to 355°C, 355°C to 360°C, 360°C to 365°C, 365°C to 370°C, 370°C ℃ to 375 ℃, 375 ℃ to 380 ℃, 380 ℃ to 385 ℃, 385 ℃ to 390 ℃, 390 ℃ to 395 ℃, 395 ℃ to 400 ℃, 400 ℃ to 405 ℃, 405 ℃ to 410 ℃, 410 ℃ to 410 ℃ 415 ℃, 415 ℃ to 420 ℃, 420 ℃ to 425 ℃, 425 ℃ to 430 ℃, 430 ℃ to 435 ℃, 435 ℃ to 440 ℃, 440 ℃ to 445 ℃, 445 ℃ to 450 ℃, 450 ℃ to 455 ℃ , 455 °C to 460 °C, 460 °C to 465 °C, 465 °C to 470 °C, 470 °C to 475 °C, 475 °C to 480 °C, 480 °C to 485 °C, 485 °C to 490 °C, 490 °C to 495 °C, or It may be 490°C to 495°C. In some examples, the temperature may be 320°C to 495°C, 340°C to 485°C, 350°C to 475°C, or 370°C to 475°C. Any suitable temperature ramp rate may be used to heat to or cool from a specified temperature. In some examples, the product has a time interval of 0.1 seconds to 1 second, 1 second to 2 seconds, 2 seconds to 3 seconds, 3 seconds to 4 seconds, 4 seconds to 5 seconds, 5 seconds to 10 seconds, 10 seconds to 15 seconds, 15 seconds. to 30 seconds, 30 seconds to 45 seconds, 45 seconds to 60 seconds, 60 seconds to 75 seconds, 75 seconds to 90 seconds, 90 seconds to 105 seconds, 105 seconds to 2 minutes, 2 minutes to 3 minutes, 3 minutes to 4 minutes, 4 minutes to 5 minutes, 5 minutes to 10 minutes, 10 minutes to 15 minutes, 15 minutes to 20 minutes, or 20 minutes to 25 minutes. In some examples, it may indicate that the temperature is maintained at or near a specified temperature or within 5° C. or within 10° C. of the specified temperature for a period of time, as the case may be. In some examples, a temperature or temperature range may be paired with a specific time or range of time. For example, the temperature may be 340° C. to 485° C. while the time period is 10 minutes or less, the temperature may be 350° C. to 475° C. while the time period is 1 minute or less, or the temperature may be 370° C. while the time period is 2 seconds to 35 seconds. It may be from ℃ to 475 ℃. Any variation or combination of temperatures and times described above may be used, and particular alloys or final product configurations may benefit from specific combinations of temperatures and times or specific temperature and time length ranges.

The intermediate annealing step 155 is annealing the cast, homogenized or rolled product at 10 m/min to 15 m/min, 15 m/min to 20 m/min, 20 m/min to 25 m/min, 25 m/min to 30 m/min. m/min, 30 m/min to 40 m/min, 40 m/min to 45 m/min, 45 m/min to 50 m/min, 50 m/min to 60 m/min, 60 m/min to 70 m/min, 70 m/min to 80 m/min, 80 m/min to 90 m/min, 90 m/min to 100 m/min, 100 m/min to 110 m/min, 110 m/min to 120 The furnace ( It may include passing through a furnace. In some examples, intermediate annealing step 155 may include heating a cast, homogenized, or rolled product by passing the product through a gas fired furnace. In some cases, intermediate annealing step 155 may include a magnetic heating unit with a heating rate between 10 °C/sec and 150 °C/sec. Optionally, the intermediate annealing step 155 may include a quenching process (e.g., water quenching or air quenching) with a cooling rate of 5° C./sec to 150° C./sec or more to return the product to room temperature or room temperature. Cold rolling (160) of the product after the intermediate annealing step (155) can produce an unrecrystallized aluminum product with deformed grains. Cold rolling (160) increases the gauge by 25% to 99% (e.g., 25% to 30%, 30% to 35%, 35% to 40%, 40% to 45%, 45%) compared to the gauge prior to cold rolling (160). % to 50%, 50% to 55%, 55% to 60%, 60% to 65%, 65% to 70%, 70% to 75%, 75% to 80%, 80% to 85%, 85% to This may be performed to produce a final gauge thickness that represents a gauge reduction of 90%, 90% to 95%, or 95% to 99%). In some specific examples, the cold rolling process can achieve a cold reduction of 55% to 75%, 25% to 90%, 45% to 95%, or 60% to 99%.

Subsequently, the product may optionally undergo one or more solution heat treatment steps (165) to form a double recrystallized aluminum product (170). The solution heat treatment 165 may be any suitable treatment for the sheet that results in solutionization of the soluble particles. By way of example, the product may be heated to a peak metal temperature (PMT) of up to 590° C. (e.g., 400° C. to 590° C.) and dipped in the PMT for a period of time to form a hot product. For example, the product can be soaked at 480° C. for 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 to a temperature of 500° C. to room temperature at a rate greater than 90° C./sec to form a heat treated product.

After quenching, the heat treated product may optionally undergo a pre-aging treatment by reheating prior to cooling. Pre-aging treatment may be performed at a temperature of about 50° C. to about 125° C. for up to 6 hours. For example, pre-aging treatment is about 50°C, about 55°C, about 60°C, about 65°C, about 70°C, about 75°C, about 80°C, about 85°C, about 90°C, about 95°C, about 100°C. It can be carried out at a temperature of about 105°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. Pre-aging treatment can be performed by passing the heat treated product through a heating device, such as a device that emits radiant heat, convective heat, inductive heat, infrared heat, etc.

FIG. 2 provides a plot showing exemplary temperatures of a cast metal product during various stages of a manufacturing process in accordance with various aspects of the present disclosure. As part of the initial casting step 205 in which the molten metal is formed into an ingot, cast article, or other solid object or metal product, the molten metal is formed by placing the metal in water or an aqueous solution, either in a direct cool casting process or in a continuous casting process involving quenching immediately after casting. The metal may be cooled and/or solidified by a process of quenching or cooling the metal by exposure to it.

After the casting step 205, the metal product may undergo a homogenization process 210, in which the metal is heated to a temperature below the metal's melting or solidification temperature. Optionally, the metal product is heated to a temperature at which the base metal and any alloying elements form a solid solution.

Following the homogenization process 210, the metal product may be subjected to one or more processes that may form the desired microcrystalline structure within the metal product, for example by stretching the metal product. This process may correspond to, for example, hot rolling 215 and/or cold rolling 220 to form a sheet, plate or sheet from a metal ingot or other cast article or metal product.

In some embodiments, exposing a metal product at an elevated temperature in a quenching or cooling process to a solution, such as water, an aqueous solution, or a gaseous solution, may be used to reduce the temperature of the metal product to a temperature that is desirable or useful for subsequent processing. . For example, exposing a metal product to water or an aqueous solution may be useful for cooling the metal product between the hot rolling process 215 and subsequent processing. Tandem and/or digestion treatments are not shown in Figure 2, but may be performed at temperatures suitable for such processes.

After the hot rolling process 215 and/or the cold rolling process 220 (cold rolling process 220 may be optional), the metal product may undergo an intermediate annealing heat treatment process 225, wherein the metal product It is heated and maintained at a predetermined temperature for no longer than a period of time to produce at least partial recrystallization of the metal product. The metal product may optionally undergo an additional cold rolling process (230) after the intermediate annealing heat treatment process (225). As shown in Figure 2, a variety of different peak temperatures can be used in the intermediate annealing heat treatment process 225, depending on, for example, the specific alloy of the metal product and/or the specific mechanical or physical properties desired for the final product. may be dependent.

The metal product may then undergo a solution heat treatment process 235, where the temperature of the metal product is a temperature above the critical temperature, such as the temperature at which precipitated components within the metal product dissolve into a solid solution or at which the recrystallization process occurs. The temperature is raised, and the metal product remains above the critical temperature for a certain period of time. When the solution heat treatment process 235 is completed, the metal product can undergo a quenching process 240, and the dissolved components are fixed in place by rapidly lowering the temperature of the metal through the quenching process. This quenching process 240 may include exposing the metal product to a solution such as water, an aqueous solution, or a quenching solution containing a gas or gas mixture.

In embodiments, the process outlined in FIG. 2 may be performed individually or as part of one or more continuous processing lines, and the metal product may be transferred as a coil, film, or web of material between processing steps. The metal product may be transferred between stages by rolling the metal product, which may be in tension, on or between rollers or, for example, by transporting the metal product on one or more conveyors. Additionally, other steps not explicitly identified may be included before, during, and/or after any of the steps identified in FIG. 2 . Other example steps include, but are not limited to, tandem and/or disassembly steps, washing steps, chemical treatment steps, or finishing steps. By way of example, the finishing step may correspond to a surface anodizing step, a powder coating step, a painting step, a printing step, etc.

3 provides an overview of an exemplary method for making recrystallized aluminum products. At block 305, an unrecrystallized aluminum product is provided. Any desired technique for producing unrecrystallized aluminum products may be used, such as the casting, homogenization, hot rolling, or cold rolling steps described in Figures 1 and 2. Unrecrystallized aluminum products are 1.0 mm to 1.2 mm, 1.2 mm to 1.4 mm, 1.4 mm to 1.6 mm, 1.6 mm to 1.8 mm, 1.8 mm to 2.0 mm, 2.0 mm to 2.2 mm, 2.2 mm to 2.4 mm, 2.4 mm. to 2.6 mm, 2.6 mm to 2.8 mm, 2.8 mm to 3.0 mm, 3.0 mm to 3.2 mm, 3.2 mm to 3.4 mm, 3.4 mm to 3.6 mm, 3.6 mm to 3.8 mm, 3.8 mm to 3.0 mm, 4.0 mm to 4.2 mm, 4.2 mm to 4.4 mm, 4.4 mm to 4.6 mm, 4.6 mm to 4.8 mm, 4.8 mm to 5.0 mm, 5.0 mm to 5.2 mm, 5.2 mm to 5.4 mm, 5.4 mm to 5.6 mm, 5.6 mm to 5.8 mm, It may have a thickness of about 1.0 mm to about 7.0 mm, such as 5.8 mm to 6.0 mm, 6.0 mm to 6.2 mm, 6.2 mm to 6.4 mm, 6.4 mm to 6.6 mm, 6.6 mm to 6.8 mm, or 6.8 mm to 7.0 mm. there is. The unrecrystallized aluminum product may be, for example, a cold rolled aluminum product and/or a hot rolled aluminum product.

At block 310, the unrecrystallized aluminum product undergoes an annealing heat treatment at a predetermined temperature of up to 495° C. for a time of up to 25 minutes to produce a recrystallized aluminum product. Annealing heat treatment may use a self-heating process or may involve passing the unrecrystallized aluminum product through a gas fired furnace. The speed of unrecrystallized aluminum product passing through the furnace can be between 10 m/min and 200 m/min. In one example, the annealing heat treatment occurs at a temperature of up to 350° C. for up to 1 minute. The recrystallized product has a length of about 1.0 mm to about 7.0 mm (e.g., 1.0 mm, 1.5 mm, 2.0 mm, 2.2 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, It may have a thickness of 6.5 mm, or 7.0 mm).

At block 315, the recrystallized aluminum product undergoes a cold rolling process to produce a cold rolled aluminum product. The cold rolling process can result in a cold reduction of 25% to 99%, such as 25% to 90%, 45% to 95%, or 55% to 75% or 60% to 99%.

At block 320, the cold rolled product undergoes a solution heat treatment to produce a double recrystallized aluminum product. Double recrystallized aluminum products produced by intermediate annealing heat treatment and solution heat treatment can exhibit improved physical properties such as reduced rope and improved bending and elongation properties. For example, roping can be characterized by the surface arithmetic mean height (Sa). In some examples, the recrystallized aluminum product optionally has a size of 0.01 μm to 0.05 μm, 0.05 μm to 0.10 μm, 0.10 μm to 0.50 μm, 0.50 μm to 1.0 μm, 1.0 μm to 5.0 μm, 5.0 μm to 10 μm. ㎛, 10 ㎛ to 15 μm, 15 μm to 20 μm, 20 μm to 25 μm, 25 μm to 30 μm, 30 μm to 35 μm, 35 μm to 40 μm, 40 μm to 45 μm, or 45 μm to 50 μm. 0.50 ㎛ Alternatively, it may represent a surface arithmetic mean height (Sa) of 0.01 ㎛ to 50 ㎛. Additionally, the recrystallized product optionally has a bending value of up to 0.55 f10% in the transverse direction, such as 0.01 to 0.55, or a bending value of up to 0.70 f15% in the transverse direction, such as 0.01 to 0.70. It can be expressed. In some examples, the f10% bending value in the transverse direction is 0.01 to 0.05, 0.05 to 0.10, 0.10 to 0.15, 0.15 to 0.20, 0.20 to 0.25, 0.25 to 0.30, 0.30 to 0.35, 0.35 to 0.40, 0.40 to 0.45 , 0.45 to It may be 0.50, or 0.50 to 0.55. In some examples, the f15% bending value in the transverse direction is 0.01 to 0.05, 0.05 to 0.10, 0.10 to 0.15, 0.15 to 0.20, 0.20 to 0.25, 0.25 to 0.30, 0.30 to 0.35, 0.35 to 0.40, 0.40 to 0.45 , 0.45 to It may be 0.50, 0.50 to 0.55, 0.55 to 0.60, 0.60 to 0.65, or 0.65 to 0.70. The f bending modulus can be measured according to ASTM E290, where f=r/t, for a given pre-strain, r is the lowest radius of bend without any visible surface cracks and t is the sheet thickness after deformation. For example, f10% is the bending modulus after pre-strain of 10% in the transverse direction. The recrystallized product may additionally or alternatively exhibit a uniform elongation of at least 21%, such as 21% to 99% or greater. The recrystallized product may additionally or alternatively exhibit a conductivity of 25 mΩ/m to 40 mΩ/m. The recrystallized product may comprise an average precipitate size of 0.05 μm to 0.5 μm, undissolved precipitates occupy an area fraction of 0% to 1% of the recrystallized product, and/or microvoids represent 0% of the recrystallized product. It occupies an area ratio of 0.3%.

Recrystallized aluminum alloy products

4A and 4B provide schematic drawings of an exemplary unrecrystallized product 410 and an exemplary recrystallized product 420. For example, unrecrystallized product 410 may be a cast, homogenized, hot rolled, and/or cold rolled aluminum product. Recrystallized product 420 may be unrecrystallized product 410 after undergoing an annealing heat treatment, as described herein, of heating and holding at a temperature below 495° C. for up to 25 minutes. In the unrecrystallized product 410, the particles 412 have an elongated nature (e.g., length greater than width). Conversely, in the recrystallized product 420, the particles 432 have more uniform properties (e.g., length and width sizes that are relatively close together). It will be appreciated that the examples of unrecrystallized product 410 and recrystallized product 420 are for illustrative purposes only and are not to scale.

As described above, the recrystallized product 420 has been subjected to the same processing conditions, in particular, except that it is not subjected to the short-term, low-temperature intermediate annealing heat treatment described above, such as at 400 ° C. or 350 ° C. for up to 25 minutes or 1 minute. It can be further processed to produce aluminum alloy products that exhibit reduced roping and improved bending and elongation properties when compared to other aluminum alloy products.

In some cases, precipitates present in the product may grow during recrystallization, which is achieved by a short-term low-temperature annealing heat treatment, due to increased diffusion of constituent elements under the elevated temperature conditions of the short-term low-temperature annealing heat treatment process. In some cases, small precipitates present in the product may dissolve during recrystallization, which is achieved with short-term low-temperature annealing heat treatments. The presence of undissolved precipitates may be undesirable, thus ensuring subsequent continuous annealing and solution heat treatment. In some extreme cases, precipitates present in the product may grow to a size large enough to not completely dissolve during the subsequent continuous annealing and solution heat treatment, thereby reducing the amount of recrystallization achieved and the precipitate at the end of the short-term low temperature annealing heat treatment process. It may be desirable to strike a balance between the average sizes of

Methods of using the disclosed aluminum alloy products

The aluminum alloy products described herein may be used in automotive applications and other transportation applications, including aircraft and railroad applications. For example, the disclosed aluminum alloy products include bumpers, side beams, roof beams, cross beams, pillar reinforcements (e.g., A-pillars, B-pillars and C-pillars), interior panels, exterior panels, side panels, interior hoods, It can be used to manufacture automotive structural parts such as exterior hoods or trunk lid panels. The aluminum alloy products and methods described herein may also be used in aircraft or rail vehicle applications, for example, to manufacture exterior and interior panels.

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

Metal and metal alloy processing methods

Methods for processing metals and metal alloys, including aluminum, aluminum alloys, magnesium, magnesium alloys, magnesium composites, steel, etc., and the resulting treated metals and metal alloys are described herein. In some examples, the metal for use in the methods described herein is an aluminum alloy, such as 1xxx series aluminum alloy, 2xxx series aluminum alloy, 3xxx series aluminum alloy, 4xxx series aluminum alloy, 5xxx series aluminum alloy, 6xxx series aluminum alloy, Includes 7xxx series aluminum alloy, or 8xxx series aluminum alloy. In some examples, materials for use in the methods described herein include aluminum, aluminum alloys, magnesium, magnesium-based materials, magnesium alloys, magnesium composites, titanium, titanium-based materials, titanium alloys, copper, copper-based materials, composites, composites. Non-ferrous materials, including sheets or other suitable metals, non-metals or combinations of materials, may be used. Monolithic and non-monolithic materials such as rolled joint materials, clad alloys, clad layers, composite materials such as (but not limited to) carbon fiber containing materials, or various other materials are also useful in the methods described herein. In some instances, aluminum alloys containing iron are useful in the methods described herein.

By way of non-limiting example, exemplary 1xxx series aluminum alloys for use in the methods described herein 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.

Non-limiting exemplary 2xxx series aluminum alloys for use in the methods described herein include AA2001, AA2002, AA2004, AA2005, AA2006, AA2007, AA2007A, AA2007B, AA2008, AA2009, AA2010, AA2011, AA2011A, AA2111, AA2111A, , 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, , AA2037, AA2038, AA2039, AA2139, AA2040, AA2041, AA2044, AA2045, AA2050, AA2055, AA2056, AA2060, AA2065, AA2070, AA2076, AA2090, AA2091, AA2094, AA2095, AA2195, AA2295, AA2196, AA2296, AA2097, AA222 97, AA2397, AA2098, AA2198, AA2099, Or it may include AA2199.

Non -limited 3XXX series aluminum alloys for use in the methods described herein are AA3002, AA3103, AA3103A, AA3103B, AA3203, AA3403, AA3004, AA3004a, AA3204 , AA3005A, AA3105, AA3105A, AA3105B, AA3007, AA3107, AA3207, AA3207A, AA3307, AA3009, AA3010, AA3110, AA3011, AA3012, AA3012A, AA3013, AA3014, AA3015, AA3016, AA3017, AA3019, , AA3021, AA3025, AA3026, AA3030, AA3130, Or it may include AA3065.

Non-limiting exemplary 4xxx series aluminum alloys for use in the methods described herein include AA4004, AA4104, AA4006, AA4007, AA4008, AA4009, AA4010, AA4013, AA4014, AA4015, AA4015A, AA4115, AA4016, AA4017, AA4018, AA4019, It may include AA4020, AA4021, AA4026, AA4032, AA4043, AA4043A, AA4143, AA4343, AA4643, AA4943, AA4044, AA4045, AA4145, AA4145A, AA4046, AA4047, AA4047A, or AA4147.

Non-limiting exemplary 5xxx series aluminum alloy products for use in the methods described herein 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, 9, 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, AA 5180, AA5180A, AA5082, AA5182, AA5083, AA5183 , AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

Non-limiting exemplary 6xxx series aluminum alloys for use in the methods described herein include AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, 5, 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, AA6 055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A, AA6261, AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, AA606, 4, AA6064A, AA6065, AA6066, AA6068, AA6069, It may include AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091, or AA6092.

Non-limiting exemplary 7xxx series aluminum alloys for use in the methods described herein 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, AA 7026, AA7029, AA7129, AA7229, AA7032, AA7033, AA7034, AA7036, AA7136, AA7037, AA7040, AA7140, AA7041, AA7049, AA7049A, AA7149,7204, AA7249, AA7349, AA7449, AA7050, AA7050A, AA7150, AA7250, AA7055, AA7 155, AA7255, AA7056, AA7060, AA7064, It may include AA7065, AA7068, AA7168, AA7175, AA7475, AA7076, AA7178, AA7278, AA7278A, AA7081, AA7181, AA7185, AA7090, AA7093, AA7095, or AA7099.

Non-limiting exemplary 8xxx series aluminum alloys for use in the methods described herein 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, AA8090, It may include AA8091, or AA8093.

The examples disclosed herein serve to further illustrate aspects of the invention but do not limit it. Conversely, after reading the description herein, it should be clearly understood that various embodiments, modifications and equivalents may be suggested to those skilled in the art without departing from the spirit of the invention. The examples and embodiments described herein may utilize conventional procedures, unless otherwise noted. Some procedures are described herein for illustrative purposes.

Example 1

Ten alloys were prepared to evaluate the properties of aluminum alloy sheet metal products after short-term low-temperature annealing heat treatment by comparing them with those of other aluminum sheet metal products. Table 1 shows the alloy, final thickness of aluminum sheet metal products and natural aging period of aluminum sheet metal products. Table 2 shows the alloy composition of aluminum sheet metal products. Comparative alloys 1 and 2 (CA1 and CA2) were prepared by casting, homogenization, hot rolling, and cold rolling. Comparative alloys 3 and 4 (CA3 and CA4) were prepared similarly to comparative alloys 1 and 2 and underwent two conventional solution heat treatments after the cold rolling step. Variant A, Variant B, Variant C, Variant D, Variant E and Variant F are subjected to an initial cold rolling step followed by a low temperature intermediate annealing heat treatment (e.g., process 155 referred to in connection with Figure 1) followed by further cold rolling and conventional heating. It was an aluminum alloy produced through a phosphorus solution heat treatment (e.g., process 165 referred to in connection with Figure 1). Variant D, Variant E and Variant F were the same aluminum alloy produced by varying the length of the intermediate annealing heat treatment. The intermediate annealing heat treatment of variant D was 15 seconds, the intermediate annealing heat treatment of variant E was 25 seconds, and the intermediate annealing heat treatment of variant F was 35 seconds.

Table 1

Table 2

Example 2

The strength properties of various alloys described in Example 1 were tested and are summarized in Figures 5A, 5B, 5C, 5D, 5E and 5F. Yield strength (Figures 5a and 5b), total tensile strength (Figures 5c and 5d) and ratio of yield strength to total tensile strength (Figures 5e and 5f) are shown, where L, T and D are respectively Corresponds to measurements in the longitudinal, transverse and diagonal directions. Variant A, variant B, variant C, variant D, variant E and variant F exhibit similar properties to each other in the longitudinal, transverse and diagonal directions. Deformation A, Deformation B, Deformation C, Deformation E, and Deformation F each exhibit improved strength properties compared to Comparative Alloy 1 and similar strength properties to Comparative Alloy 2, Comparative Alloy 3, and Comparative Alloy 4.

Example 3

The elongation properties of various alloys described in Example 1 were tested and are summarized in Figures 6A, 6B, 6C, 6D, 6E, 6F, 6G, and 6H. Uniform elongation (Figures 6a and 6b), total elongation (Figures 6c and 6d), strain hardening exponent for 5% strain (Figures 6e and 6f), and strain hardening exponent for 10-20% strain (Figure 6g). and Figure 6h) were evaluated for each alloy. Variant A, variant B, variant C, variant D, variant E and variant F each exhibit a uniform elongation of at least 21% in the longitudinal, transverse and diagonal directions. The variant outperforms Comparative Alloy 2 and Comparative Alloy 4 in each elongation characteristic and exhibits similar properties to Comparative Alloy 3. Variant B, Variant D, Variant E and Variant F show similar results to Comparative Alloy 1.

Example 4

Additional deformation, bending and surface properties of various alloys described in Example 1 were tested and are shown in Figures 7A, 7B, 7C, 7D, 7E, 7F, 7G and 8. The bending values for 10% pre-strain (FIGS. 7a and 7b) and 15% pre-strain (FIGS. 7c and 7d) and the Lankford ratio at 10% strain (8% to 12%) are were evaluated (Figures 7e and 7f). In the transverse direction, variant A, variant B, variant C, variant D, variant E, and variant F performed better than Comparative Alloy 1, Comparative Alloy 2, Comparative Alloy 3, and Comparative Alloy 4 for all bending tests, respectively. To characterize the roping of the alloy, arithmetic mean height, Sa and surface profile analysis were also evaluated using the fast Fourier transform (FFT) method (Figure 7g). The FFT can be compared to the roping value measurement according to VDA 239-400 Recommendation (RK). Compared to Comparative Alloy 1 and Comparative Alloy 2, Variant A, Variant B, and Variant C have smaller roping and are similar to Comparative Alloy 3. Surface profiles were evaluated for Comparative Alloy 1, Comparative Alloy 4, and Variant D (Figure 8). Comparative alloy 4 outperforms the other two alloys, and variant D outperforms comparative alloy 1.

Example 5

The particle and precipitate properties of Comparative Alloy 1, Comparative Alloy 2, Variant B, and Variant C alloys were evaluated. 9A is an exemplary microscopic image of a hot rolled aluminum product showing the stretched grain structure. As shown in the upper panel of Figure 9b, the particles are further elongated after cold rolling to 2.2 mm. The lower panel of Figure 9b highlights the precipitates present in the aluminum matrix and shows many fine precipitates, although some large precipitates can also be seen. After cold rolling, aluminum products undergo a short-term low-temperature annealing heat treatment in which they are heated to 350 °C for 5 seconds, causing at least some of the metal to recrystallize. Figure 9c shows the recrystallized grain structure in the upper panel, and the lower panel shows that many of the small precipitates have dissolved but some have grown in size. Figure 10A shows a cross section of the recrystallized grain structure of Comparative Alloy 1, Variant B, and Variant D. Figure 10B shows the surfaces of the recrystallized grain structures of Comparative Alloy 1, Variant B, and Variant D. Comparative alloy 1 has finer grains than variant B and variant D, and variant D has finer grains than variant B. Figure 11A shows a bar graph showing the area percentage of undissolved precipitate and the equivalent circular diameter (ECD) of undissolved precipitate, with variant C shown as having the smallest area percentage of undissolved precipitate. Figure 11b shows a bar graph representing the conductivity of each alloy, which may indicate the amount of dissolved precipitate, and both Variant B and Variant C have lower conductivities than Comparative Alloy 2 and Comparative Alloy 1, showing that a short-term low-temperature annealing heat treatment It is possible that this indicates that at least some of the precipitate has dissolved.

Example 6

Microscopic images of samples of Comparative Alloy 1, Comparative Alloy 2, Variant B, Variant C, and Variant D alloy were obtained and are shown in Figure 12. This image shows the microstructure of five alloys, with small dark spots within the grains corresponding to undissolved precipitates and white spots around and adjacent to the undissolved precipitates corresponding to microvoids. Figure 13A provides a bar graph showing the area ratio of micropores and the ECD of micropores. Figure 13b provides a bar graph showing the area fraction of undissolved precipitate and the ECD of undissolved precipitate. Variants B and C showed fewer and smaller micropores than Comparative Alloy 2 and Comparative Alloy 1. Figure 14 provides bar graphs showing micropores and undissolved precipitates for Comparative Alloy 1, Variant B, and Variant D. Both Variant B and Variant D show fewer microvoids and undissolved precipitates than Comparative Alloy 1.

Exemplary Embodiment

As used below, any reference to a series of aspects (e.g., “aspects 1 through 4”) or a group of unlisted aspects (e.g., “a preceding or subsequent aspect”) refers to each of those aspects. They are to be understood as separate references (e.g., “aspects 1 to 4” should be read as “aspects 1, 2, 3 or 4”).

Aspect 1 is a method comprising providing an unrecrystallized aluminum product; subjecting the unrecrystallized aluminum product to an intermediate annealing heat treatment at a predetermined temperature of 495° C. or less for a time of 25 minutes or less to produce a recrystallized aluminum product; subjecting the recrystallized aluminum product to a cold rolling process to produce a cold rolled aluminum product; and subjecting the cold rolled aluminum product to a solution heat treatment to produce a double recrystallized aluminum product.

Embodiment 2 is the method of any preceding or subsequent aspect, wherein the predetermined temperature is 280°C to 495°C or 320°C to 495°C.

Embodiment 3 is the method of any preceding or subsequent aspect, wherein the predetermined temperature is 300° C. to 430° C. and the time is 10 minutes or less, or alternatively, the predetermined temperature is 340° C. to 485° C. and the time is 10 minutes or less. .

Embodiment 4 is the method of any preceding or subsequent aspect, wherein the predetermined temperature is from 330° C. to 400° C. and the time is less than 1 minute, or alternatively, the predetermined temperature is from 350° C. to 475° C. and the time is less than 1 minute. .

Embodiment 5 is the method of any preceding or subsequent aspect, wherein the predetermined temperature is from 345°C to 385°C and the time is from 2 seconds to 35 seconds, or the predetermined temperature is from 370°C to 470°C and the time is from 2 seconds to 35°C. It's 35 seconds.

Aspect 6 is the method of any preceding or subsequent aspect, wherein the cold rolling process achieves a cold reduction of 55% to 75%.

Aspect 7 is the method of any preceding or subsequent aspect, wherein the cold rolling process achieves a cold reduction of 25% to 90%.

Aspect 8 is the method of any preceding or subsequent aspect, wherein the cold rolling process achieves a cold reduction of 45% to 95%.

Aspect 9 is the method of any preceding or subsequent aspect, wherein the cold rolling process achieves a cold reduction of 60% to 99%.

Embodiment 10 is the method of any preceding or subsequent aspect, wherein the double recrystallized aluminum product exhibits a surface arithmetic mean height (Sa) of at most 0.50 μm.

Embodiment 11 is the method of any preceding or subsequent embodiment, wherein the double recrystallized aluminum product exhibits an f10% bending value of at most 0.55 in the transverse direction.

Embodiment 12 is the method of any preceding or subsequent aspect, wherein the double recrystallized aluminum product exhibits an f15% bending value of up to 0.70 in the transverse direction.

Embodiment 13 is the method of any preceding or subsequent aspect, wherein the double recrystallized aluminum product exhibits a uniform elongation of at least 21%.

Embodiment 14 is the method of any preceding or subsequent aspect, wherein the double recrystallized aluminum product has a thickness of 1.00 mm to 3.5 mm.

Embodiment 15 is the method of any preceding or subsequent aspect, wherein the double recrystallized aluminum product comprises an average precipitate size of from 0.05 μm to 0.5 μm.

Embodiment 16 is the method of any preceding or subsequent aspect, wherein the undissolved precipitate accounts for an area fraction of 0% to 1% of the double recrystallized aluminum product.

Embodiment 17 is the method of any preceding or subsequent aspect, wherein the microvoids occupy an area fraction of 0% to 0.3% of the recrystallized aluminum product.

Embodiment 18 is the method of any preceding or subsequent aspect, wherein the recrystallized aluminum product exhibits a conductivity of 25 mΩ/m to 40 mΩ/m.

Embodiment 19 is the method of any preceding or succeeding aspect, wherein the predetermined temperature is up to 350°C.

Aspect 20 is the method of any preceding or succeeding aspect, wherein the time is up to 5 minutes.

Aspect 21 is the method of any preceding or succeeding aspect, wherein the time is at most 1 minute.

Embodiment 22 is the method of any preceding or subsequent aspect, wherein the intermediate annealing heat treatment includes passing the unrecrystallized aluminum product through the furnace at a rate of 10 m/min to 200 m/min.

Aspect 23 is the method of any preceding or subsequent aspect, wherein the intermediate annealing heat treatment includes heating the unrecrystallized aluminum product using a self-heating process.

Aspect 24 is the method of any preceding or subsequent aspect, wherein the intermediate annealing heat treatment includes heating the unrecrystallized aluminum product by passing it through a gas fired furnace.

Embodiment 25 is the method of any preceding or subsequent aspect, wherein the unrecrystallized aluminum product comprises a 6xxx series aluminum alloy.

Embodiment 26 is the method of any preceding or subsequent aspect, wherein the unrecrystallized aluminum product comprises a 7xxx series aluminum alloy.

Embodiment 27 is a rolled aluminum alloy product comprising a 6xxx series aluminum alloy or a 7xxx series aluminum alloy, wherein the Sa of the 6xxx series aluminum alloy or 7xxx series aluminum alloy is at most 0.50 μm; The thickness of rolled aluminum alloy products is 1.00 mm to 3.5 mm; Undissolved precipitates occupy an area fraction of 0% to 1% in rolled aluminum alloy products.

Aspect 28 is the rolled aluminum alloy product of any preceding or subsequent aspect, wherein the rolled aluminum alloy product exhibits a conductivity of 25 mΩ/m to 40 mΩ/m.

Aspect 29 is the rolled aluminum alloy product of any preceding or subsequent aspect, wherein the rolled aluminum alloy product includes an average precipitate size of from 0.05 μm to 0.50 μm.

Aspect 30 is the rolled aluminum alloy product of any preceding or subsequent aspect, wherein the microvoids occupy an area fraction of 0% to 0.3% of the rolled aluminum alloy product.

All patents and publications cited herein are incorporated by reference in their entirety. The foregoing description of embodiments, including illustrative embodiments, has been presented for purposes of illustration and description only and is not intended to be exhaustive or limiting to the precise form disclosed. Numerous modifications, variations and uses will be apparent to those skilled in the art.

Claims (30)

As a method, the method includes:
providing an unrecrystallized aluminum product;
subjecting the unrecrystallized aluminum product to an intermediate annealing heat treatment at a predetermined temperature of 495° C. or less for a length of time of 25 minutes or less to produce a recrystallized aluminum product;
subjecting the recrystallized aluminum product to a cold rolling process to produce a cold rolled aluminum product; and
A method comprising subjecting the cold rolled aluminum product to a solution heat treatment to produce a dual-recrystallized aluminum product. The method of claim 1, wherein the predetermined temperature is between 320°C and 495°C. The method of claim 1, wherein the predetermined temperature is 340° C. to 485° C. and the time is 10 minutes or less. The method of claim 1, wherein the predetermined temperature is between 350° C. and 475° C. and the time is less than 1 minute. The method of claim 1, wherein the predetermined temperature is between 370° C. and 470° C. and the time is between 2 seconds and 35 seconds. The method of claim 1, wherein the cold rolling process achieves a cold reduction of 55% to 75%. The method of claim 1, wherein the cold rolling process achieves a cold rolling reduction of 25% to 90%. The method of claim 1, wherein the cold rolling process achieves a cold rolling reduction of 45% to 95%. The method of claim 1, wherein the cold rolling process achieves a cold rolling reduction of 60% to 99%. The method of claim 1 , wherein the double recrystallized aluminum product exhibits a surface arithmetic mean height (Sa) of at most 0.50 μm. The method of claim 1, wherein the double recrystallized aluminum product exhibits an f10% bending value in the transverse direction of at most 0.55. 2. The method of claim 1, wherein the double recrystallized aluminum product exhibits an f15% bending value in the transverse direction of at most 0.70. The method of claim 1, wherein the double recrystallized aluminum product exhibits a uniform elongation of at least 21%. The method of claim 1, wherein the double recrystallized aluminum product has a thickness of 1.00 mm to 3.5 mm. The method of claim 1 , wherein the double recrystallized aluminum product comprises an average precipitate size of 0.05 μm to 0.5 μm. The method of claim 1, wherein undissolved precipitate accounts for an area fraction of 0% to 1% of the double recrystallized aluminum product. The method of claim 1, wherein microvoids occupy an area fraction of 0% to 0.3% of the double recrystallized aluminum product. The method of claim 1 , wherein the double recrystallized aluminum product exhibits a conductivity of 25 mΩ/m to 40 mΩ/m. The method of claim 1, wherein the predetermined temperature is at most 350°C. The method of claim 1, wherein the time is at most 5 minutes. The method of claim 1, wherein the time is at most 1 minute. The method of claim 1, wherein the intermediate annealing heat treatment comprises passing the unrecrystallized aluminum product through a furnace at a speed of 10 m/min to 200 m/min. The method of claim 1, wherein the intermediate annealing heat treatment includes heating the unrecrystallized aluminum product using a self-heating process. The method of claim 1, wherein the intermediate annealing heat treatment includes heating the unrecrystallized aluminum product by passing it through a gas fired furnace. 2. The method of claim 1, wherein the unrecrystallized aluminum product comprises a 6xxx series aluminum alloy. The method of claim 1 , wherein the unrecrystallized aluminum product comprises a 7xxx series aluminum alloy. A rolled aluminum alloy product, wherein the rolled aluminum alloy product includes:
A 6xxx series aluminum alloy or a 7xxx series aluminum alloy, wherein the Sa of the 6xxx series aluminum alloy or 7xxx series aluminum alloy is at most 0.50 μm;
The thickness of the rolled aluminum alloy product is 1.00 mm to 3.5 mm;
A rolled aluminum alloy product, wherein undissolved precipitates occupy an area ratio of 0% to 1% in the rolled aluminum alloy product. 28. The rolled aluminum alloy product of claim 27, wherein the rolled aluminum alloy product exhibits a conductivity of 25 mΩ/m to 40 mΩ/m. 28. The rolled aluminum alloy product of claim 27, wherein the rolled aluminum alloy product comprises an average precipitate size of 0.05 μm to 0.5 μm. 28. The rolled aluminum alloy product of claim 27, wherein the microvoids occupy an area percentage of 0% to 0.3% of the rolled aluminum alloy product.

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