KR20220105167A - Engineered can body material and can end material and methods of making and using the same - Google Patents

Abstract

This application discloses aluminum alloy products, such as can body materials and can end materials, which have improved processing quality in high-speed production equipment due to their engineered surfaces. For can body materials, processing is improved by providing at least two different surface roughnesses. For can end materials, processing is improved by reducing anisotropy at least at the top and bottom surfaces of the can end material.

Description

Engineered can body material and can end material and methods of making and using the same

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority and the benefit of the application to U.S. Provisional Patent Application Serial No. 62/964,741, filed on January 23, 2020, which is incorporated herein by reference in its entirety.

Field

The present disclosure relates to aluminum alloy articles and properties thereof. The present disclosure also relates to a can body material, a can end material and a method of making and processing the same.

background

Metal cans are well known and widely used as beverage containers. Beverage can bodies are manufactured at high production rates and are designed to further increase the production rate of beverage cans by eliminating metal-related clogging in cupper presses, tear-offs and split domes in bodymakers. Demand continues to grow. However, existing aluminum can body materials can cause a decrease in productivity of can body production when tension and friction forces are not balanced during the can body production process. In addition, the inherent formability of the existing anisotropic aluminum can end material may cause draw-off due to non-uniform frictional force.

summary

Included embodiments of the invention are defined by the claims rather than this summary. This Summary is a high-level overview of various aspects of the invention and introduces some of the concepts 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 to determine the scope of the claimed subject matter. The subject matter should be understood with reference to the appropriate portion of the entire specification, any or all drawings, and each claim.

In one aspect, an aluminum alloy article having two different surface roughnesses for use as a can body sheet is disclosed herein. The aluminum alloy article may have at least two surfaces, each independently having an average surface roughness, which may be abbreviated as Ra. The aluminum alloy article in this example comprises a first surface having a first average surface roughness and a second surface having a second average surface roughness, wherein the first average surface roughness is a second average surface roughness as measured by a surface roughness meter. at least 20% lower than In some examples, the first average surface roughness is less than 0.4 μm. In some examples, the second average surface roughness is at least 0.4 μm.

In some cases, the aluminum alloy is a 3xxx series aluminum alloy, such as an AA3104 aluminum alloy. In some examples, the aluminum alloy has about 0.05 - 0.25 wt. % Cu, up to about 0.8 wt. % Fe, about 0.8 - 1.3 wt. % Mg, about 0.8 - 1.4 wt. % Mn, up to about 0.6 wt. % Si, up to about 0.1 wt. % Ti, up to about 0.25 wt. % Zn, up to about 0.05 wt. % impurities, and Al.

In some examples, the aluminum alloy article has a thickness of less than about 4 millimeters (mm).

In a second aspect, disclosed herein is a method of making a can body from the can body sheet described above. A method of making a can body includes contacting a sheet aluminum alloy product with a cupping press to form a cup. The cup includes a cup inner surface having a cup inner surface average surface roughness and a cup outer surface having a cup outer surface average surface roughness, wherein the cup inner surface average surface roughness is greater than the cup outer surface average surface roughness. The method also includes contacting the cup inner surface with the punch sleeve and the cup outer surface with an ironing die and ironing the cup to a desired height. In some examples, the method further includes trimming the wall to form the can body.

In some examples, the cup has an outer surface average surface roughness Ra (referred to herein as the cup outer surface average surface roughness) that is less than 0.4 μm. In some examples, the cup has an inner surface average surface roughness Ra (referred to herein as cup inner surface average surface roughness) of at least 0.4 μm. In some examples, the can body has an inner surface having a can body inner surface average surface roughness and an outer surface having a can body outer surface average surface roughness, wherein the can body inner surface average surface roughness is greater than the can body outer surface average surface roughness At least 10% larger.

In a third aspect, disclosed herein is an aluminum alloy article for use as a can end sheet. In some examples, the can end sheet has a surface percent isotropy of greater than 80% and a formability distortion of less than 10% as measured by confocal microscopy. In some cases, the aluminum alloy article has greater than 95% isotropy.

In some examples, the aluminum alloy is a 5xxx series aluminum alloy, such as a 5182 aluminum alloy. In some examples, the aluminum alloy article has a Texture Aspect Ratio (Str) value greater than 0.7 according to ISO 25178.

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

1 is a schematic diagram of an aluminum alloy cup in accordance with some examples.
2 is a schematic diagram of a cross-section of an aluminum alloy article in accordance with some examples.
3 is a schematic view of a stamped can end in accordance with some examples.

details

An aluminum alloy, an aluminum alloy article, and a method of making the article having improved formability are described herein. The aluminum alloy compositions and methods described herein provide improved aluminum alloy sheets for the efficient production of aluminum alloy articles, such as an aluminum can body having two different surface roughnesses and a can end having reduced anisotropy.

Definition and Description:

As used herein, the terms “invention,” “said invention,” “this invention,” and “invention” are intended to refer broadly to all subject matter of this patent application and the claims that follow. Statements containing these terms are not to be construed as limiting the subject matter described herein or limiting the meaning or scope of the following claims.

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

In this description, reference is made to alloys identified by aluminum industry designations such as “series” or “3xxx”. For an understanding of the numbering naming 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” published by The Aluminum Association or See "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 about 100 mm It may refer to an aluminum article having an excess thickness.

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

As used herein, a sheet generally refers to an aluminum article 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, less than about 0.3 mm, or less than about 0.1 mm.

As used herein, the term foil refers to an alloy thickness in the range of up to about 0.2 mm (ie, 200 microns (μm)). For example, foils can be up to 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 0 μm, 120 0 μm, 130 μm, 140 μm. , 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, or 200 μm.

All ranges disclosed herein are to be understood to include any and all subranges subsumed therein. For example, a specified range of “1 to 10” includes any and all subranges between the minimum value of 1 and the maximum value of 10 inclusive; That is, it should be considered to include all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 1 to 6.1, eg 5.5 to 10, and a maximum value of 10 or less.

The aluminum alloys herein are described in terms of elemental composition in weight percentages (wt. %) based on the total weight of the alloy. In a particular example of each alloy, the balance is aluminum, with a maximum wt. % is 0.15%.

Aluminum can body and manufacturing method thereof

For example, an aluminum alloy article for use as an aluminum can body is described herein. The aluminum alloy article may be a sheet having a substantially planar shape having at least two surfaces, such as a top surface and a bottom surface. A "substantially" plane is, for the purposes of this application, a dimension of 50% or less, 40% or less, 30% or less, 20% or less, 10% or less, 5% or less in the z-axis, or in the x- or y-axis. means having a dimension of 1% or less. For example, the sheet may have dimensions of substantially one meter in the x-axis, 1000 meters in the y-axis, and one millimeter in the z-axis.

In some examples, the aluminum alloy product is a can body sheet. The difference in surface roughness on both sides of the sheet results in improved processing quality compared to the conventional can body sheet in which there is no substantial difference in surface roughness. In another example, thicker or thinner aluminum alloy articles, such as shades or foils, can each have different surface roughness leading to improved processing characteristics.

The top and bottom surfaces of the aluminum alloy article may have different surface roughness Ra, such as a first surface having a first average surface roughness and a second surface having a second average surface roughness. In some cases, the first average surface roughness is at least 20% lower than the second average surface roughness. In other cases, the first average surface roughness is at least 21%, at least 22%, at least 23%, at least 24%, at least 25%, at least 26%, at least 27%, at least 28%, at least 29% greater than the second average surface roughness. %, at least 30%, at least 35%, at least 40%, at least 45%, at least 50%, at least 55%, at least 50%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, At least 90%, or at least 95% lower. For example, when the first side roughness is measured and recorded as the Ra value, when the Ra value of the second side is 1.0 μm, the maximum surface roughness Ra value of the first surface is determined such that the first average surface roughness is equal to the second average surface roughness. It will be 0.80 μm when it is at least 20% smaller than the roughness.

Surface roughness can be measured by any method known in the art. In general, surface roughness meters are used to measure and describe surface features that are reported as "average surface roughness". The term average surface roughness is used to convey that the surface features may repeat in a regular and consistent manner, such as the surface features of an egg carton, or may not repeat in an irregular and consistent manner, such as the surface of a mountain range. In general, "average surface roughness" measures and records the average distance from the plane. For example, a two-dimensional (2D) or three-dimensional (3D) roughness meter may be used to determine the average surface roughness. In some cases, the roughness meter measures average surface roughness using a stylus; In other cases, optical methods may be used. One skilled in the art will understand that one particular method may be designated, but that any method capable of detecting the difference in the average roughness of two different surfaces may be used, and that the difference between the two dimensions may be expressed as a percentage. In some examples, the average surface roughness is measured by confocal microscopy. Surfaces are characterized herein by a variety of parameters, including Ra and Rz, measured in micrometers (microns) and known to those skilled in the art. Optionally, the parameters can be measured using MountainsMap® Surface Imaging and Metrology software (Digital Surf; Besancon, France). All roughness values can be measured mechanically with a standard stylus. In another example, the average surface roughness is measured and reported as Str according to ISO 25178 [2019]. The Str value is the ratio of the shortest wavelength to the longest wavelength measured in any direction with respect to the rolling direction.

During production of a can body, such as a beverage can body, the can body sheet is subjected to two-piece drawing and wall ironing. The can body sheet is first contacted with a cupping press to form a cup, and then the cup is transferred to a punch sleeve for drawing and ironing. As shown in FIG. 1 , the cup 10 has an inner surface 11 and an outer surface 12 .

During drawing and ironing, it is necessary to balance the friction between the punch sleeve and the inner surface of the cup and the tension between the ironing die and the outer surface of the cup. Without wishing to be bound by theory, when tension and friction are balanced, fracturing is reduced. Without wishing to be bound by theory, when tension and friction are balanced, fracturing is reduced. With the materials and processes disclosed herein, rather than reducing the tension between the outer surface of the cup and the ironing die (e.g., by the use of additional lubricant), friction between the punch sleeve and the inner surface of the cup makes contact with the punch sleeve. This is increased by having a rougher surface and a smoother outer surface in contact with the ironing die. Accordingly, the materials and methods disclosed herein have the advantage of reducing can body crushing and also reducing the amount of lubricant. Although materials and methods are described in some examples with respect to can body sheets, those skilled in the art will be punched, stamped, drawn and It will be appreciated that/or is applicable to any aluminum alloy product that has been ironed. Accordingly, the aluminum alloy product may be a shade, sheet, or foil. In addition, those skilled in the art will understand that the average surface roughness required to balance tension and friction, and the difference between the two average surface roughnesses required, may vary depending on the design of the punch sleeve and ironing die and the particular aluminum alloy product. .

In some examples, the first surface, which may correspond to the outer surface 12 of the cup 10 , is smoother than the second surface, which may correspond to the inner surface 11 of the cup 10 . In this way, the first average surface roughness Ra of the first surface is lower than the second average surface roughness Ra of the second surface. A smoother surface will have fewer and/or fewer topographic features, such as bumps, ridges, lines and/or protrusions, than a rougher surface. In some examples, the first average surface roughness Ra is less than 0.4 μm. In another example, the first average surface roughness Ra is less than 0.38 μm, less than 0.36 μm, less than 0.34 μm, less than 0.32 μm, less than 0.28 μm, less than 0.26 μm, less than 0.24 μm, less than 0.22 μm, less than 0.2 μm, less than 0.18 μm. , less than 0.16 µm, less than 0.14 µm, less than 0.12 µm, less than 0.1 µm, less than 0.08 µm, less than 0.06 µm, less than 0.04 µm, less than 0.02 µm, or less than 0.01 µm.

In some examples, the second average surface roughness Ra is at least 0.4 μm. In another example, the second average surface roughness Ra is at least 0.6 μm, at least 0.8 μm, at least 1.0 μm, at least 1.5 μm, at least 2 μm, at least 2.5 μm, at least 3 μm, at least 3.5 μm, at least 4 μm, at least 4.5 μm. , 5 μm or greater, 5.5 μm or greater, 6 μm or greater, 6.5 μm or greater, 7 μm or greater, 7.5 μm or greater, 8 μm or greater, 8.5 μm or greater, 9 μm or greater, 9.5 μm or greater, 10 μm or greater, or 15 μm or greater .

In another aspect, a method of making an aluminum can body is described herein. The can body manufacturing method comprises contacting an aluminum alloy product having two different surface roughnesses with a cupping press to form a cup comprising a cup inner surface having a cup inner surface average surface roughness and a cup outer surface having an average cup outer surface surface roughness. forming, wherein the inner surface average surface roughness is greater than the outer surface average surface roughness; contacting the cup inner surface with the punch sleeve and contacting the cup outer surface with the ironing die; and ironing the cup to a desired height. As the rougher surface of the aluminum alloy product contacts the punch sleeve, the friction between the punch sleeve and the rougher surface balances the tension between the ironing die and the smoother surface. In some examples, the method further includes trimming the wall to form the can body.

Any of the aluminum alloy products (such as shades, sheets, or foils) described above may be used as long as the aluminum alloy products have a roughness difference on both sides. In some examples, the outer surface average surface roughness Ra of the cup is less than 0.4 μm. In another example, the outer surface average surface roughness Ra is less than 0.38 µm, less than 0.36 µm, less than 0.34 µm, less than 0.32 µm, less than 0.3 µm, less than 0.28 µm, less than 0.26 µm, less than 0.24 µm, less than 0.22 µm, less than 0.2 µm , less than 0.18 µm, less than 0.16 µm, less than 0.14 µm, less than 0.12 µm, less than 0.1 µm, less than 0.08 µm, less than 0.06 µm, less than 0.04 µm, less than 0.02 µm, or less than 0.01 µm.

In some examples, the inner surface of the cup has an average surface roughness Ra of at least 0.4 μm. In another example, the inner surface mean surface Ra is at least 0.45 μm, at least 0.5 μm, at least 0.6 μm, at least 0.8 μm, at least 1.0 μm, at least 1.5 μm, at least 2 μm, at least 2.5 μm, at least 3 μm, at least 3.5 μm, 4 μm or greater, 4.5 μm or greater, 5 μm or greater, 5.5 μm or greater, 6 μm or greater, 6.5 μm or greater, 7 μm or greater, 7.5 μm or greater, 8 μm or greater, 8.5 μm or greater, 9 μm or greater, 9.5 μm or greater, 10 μm or more, or 15 μm or more.

Can bodies made using the products and methods described herein differ from conventional can bodies in that at least a portion of the can body inner surface has an average surface roughness that is greater than the average surface roughness of the can body outer surface. Thus, in some examples, the can body includes an inner surface having a can body inner surface average surface roughness and an outer surface having a can body outer surface average surface roughness, wherein the can body inner surface average surface roughness is the can body outer surface average surface roughness At least 20% greater than the surface roughness. In other instances, the can body inner surface average surface roughness is at least 22%, at least 24%, at least 25%, at least 26%, at least 28%, at least 30%, at least 35%, at least 40% greater than the can body outer surface average surface roughness. %, at least 45%, at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, or at least 95% greater.

The aluminum alloy articles and methods described herein may be used to manufacture beverage cans, food containers, or any other desired application. In some examples, the aluminum alloy products and methods may be used to manufacture beverage can bodies.

Aluminum alloys for use in the articles and methods described herein include 3xxx series aluminum alloys. Suitable 3xxx series aluminum alloys are, for example, AA3002, AA3102, AA3003, AA3103, AA3103A, AA3103B, AA3203, AA3403, AA3004, AA3004A, AA3104, AA3204, AA3304, AA3005, AA3005A, AA3105A, AA 3 1073105A, AA3005A, AA3105, , AA3207, AA3207A, AA3307, AA3009, AA3010, AA3110, AA3011, AA3012, AA3012A, AA3013, AA3014, AA3015, AA3016, AA3017, AA3019, AA3020, AA3021, AA3025, AA30, AA30, AA3025, AA30. In some examples, the aluminum alloy is AA3104.

In some examples, alloys for use in the articles and methods described herein may have the following elemental compositions as provided in Table 1.

element Weight percentage (wt. %) Cu 0.05 - 0.4 Fe 0 - 0.9 Mg 0.8 - 3.0 Mn 0.8 - 2.0 Si 0 - 0.7 Ti 0 - 0.1 Zn 0 - 0.25 Cr 0 - 0.4 Etc 0 - 0.05 (each)0 - 0.15 (total) Al balance

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

element Weight percentage (wt. %) Cu 0.05 - 0.25 Fe 0 - 0.8 Mg 0.8 - 1.3 Mn 0.8 - 1.4 Si 0 - 0.6 Ti 0 - 0.1 Zn 0 - 0.25 Etc 0 - 0.05 (each)0 - 0.15 (total) Al balance

In some examples, the aluminum alloy is 0.05 - 0.4 wt. % Cu, up to about 0.9 wt. % Fe, about 0.8 - 3.0 wt. % Mg, about 0.8 - 2.0 wt. % Mn, up to about 0.7 wt. % Si, up to about 0.1 wt. % Ti, up to about 0.25 wt. % Zn, up to about 0.15 wt. % impurities, and Al.

In some examples, the aluminum alloy is 0.05 - 0.25 wt. % Cu, up to about 0.8 wt. % Fe, about 0.8 - 2.8 wt. % Mg, about 0.8 - 1.4 wt. % Mn, up to about 0.6 wt. % Si, up to about 0.1 wt. % Ti, up to about 0.25 wt. % Zn, up to about 0.15 wt. % impurities, and Al.

In some examples, the aluminum alloy contains 0.05 - 0.3 wt. % Cu, about 0.4 -about 0.8 wt. % Fe, about 0.8 - 2.8 wt. % Mg, about 0.1 - 1.5 wt. % Mn, about 0.25 - 0.6 wt. % Si, up to about 0.1 wt. % Ti, about 0.1 - 0.25 wt. % Zn, up to about 0.35 wt. % Cr, up to about 0.15 wt. % impurities, and Al.

In some examples, the alloys described herein contain copper (Cu) in an amount from about 0.05% to about 0.40% (e.g., from about 0.05% to about 0.35% or from about 0.10% to about 0.30%), based on the total weight of the alloy. ) is included. For example, the alloy is 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.10%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19% , 0.20%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36 %, 0.37%, 0.38%, 0.39%, or 0.40% Cu. all wt. expressed in %.

In some examples, the alloys described herein include iron (Fe) in an amount of up to about 0.9% (e.g., from about 0.3% to about 0.85% or from about 0.4% to about 0.8%) based on the total weight of the alloy. do. For example, the alloy is 0%, 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34% , 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.5%, 0.51 %, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.6%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.7%, 0.71%, 0.72%, 0.73%, 0.74%, 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.8%, 0.81%, 0.82%, 0.83%, 0.84% , 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, or 0.9% Fe. In some cases, Fe is not present in the alloy (ie 0%). all wt. expressed in %.

In some examples, the alloys described herein contain magnesium (Mg) in an amount from about 0.8% to about 3.0% (e.g., from about 0.8% to about 2.8% or from about 1.0% to about 2.5%) by total weight of the alloy. ) is included. For example, the alloy is 0.8%, 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.9%, 0.91%, 0.92%, 0.93%, 0.94% , 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1 %, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, or 3.0% Mg. all wt. expressed in %.

In some examples, the alloys described herein contain manganese (Mn) in an amount from about 0.1 % to about 2.0 % (e.g., from about 0.1 % to about 1.5 % or from about 0.5 % to about 1.5 %) by total weight of the alloy. ) is included. For example, the alloy is 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.21%, 0.22%, 0.23%, 0.24% , 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.3%, 0.31%, 0.32%, 033%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.4%, 0.41 %, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.5%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.6%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, 0.7%, 0.71%, 0.72%, 0.73%, 0.74% , 0.75%, 0.76%, 0.77%, 0.78%, 0.79%, 0.8%, 0.81%, 0.82%, 0.83%, 0.84%, 0.85%, 0.86%, 0.87%, 0.88%, 0.89%, 0.9%, 0.91 %, 0.92%, 0.93%, 0.94%, 0.95%, 0.96%, 0.97%, 0.98%, 0.99%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, or 2.0% Mn. all wt. expressed in %.

In some examples, the alloys described herein include silicon (Si) in an amount of up to about 0.7% (e.g., from about 0.25% to about 0.6% or from about 0.3% to about 0.55%) based on the total weight of the alloy. do. For example, the alloy is 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.21%, 0.22%, 0.23% , 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.3%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.4 %, 0.41%, 0.42%, 0.43%, 0.44%, 0.45%, 0.46%, 0.47%, 0.48%, 0.49%, 0.5%, 0.51%, 0.52%, 0.53%, 0.54%, 0.55%, 0.56%, 0.57%, 0.58%, 0.59%, 0.6%, 0.61%, 0.62%, 0.63%, 0.64%, 0.65%, 0.66%, 0.67%, 0.68%, 0.69%, or 0.7% Si. In some cases, Si is not present in the alloy (ie 0%). all wt. expressed in %.

In some examples, the alloys described herein include titanium (Ti) in an amount of up to about 0.1 % (e.g., from about 0.01 % to about 0.08 % or from about 0.02 % to about 0.05 %), based on the total weight of the alloy. do. For example, the alloy may comprise 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.1% Ti. In some cases, Ti is not present in the alloy (ie 0%). all wt. expressed in %.

In some examples, the alloys described herein include zinc (Zn) in an amount of up to about 0.25% (e.g., from about 0.01% to about 0.25% or from about 0.1% to about 0.2%) based on the total weight of the alloy. do. For example, the alloy is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15% , 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.21%, 0.22%, 0.23%, 0.24%, or 0.25% Zn. In some cases, Zn is not present in the alloy (ie 0%). all wt. expressed in %.

In some examples, the alloys described herein include chromium (Cr) in an amount of up to about 0.4% (e.g., from about 0.01% to about 0.35% or from about 0.05% to about 0.3%) based on the total weight of the alloy. do. For example, the alloy is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15% , 0.16%, 0.17%, 0.18%, 0.19%, 0.2%, 0.21%, 0.22%, 0.23%, 0.24%, 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.3%, 0.31%, 0.32 %, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, or 0.4% Cr. In some cases, Cr is not present in the alloy (ie 0%). all wt. expressed in %.

Optionally, the alloy compositions described herein may further comprise other trace elements, sometimes referred to as impurities, in an amount of 0.05% or less, 0.04% or less, 0.03% or less, 0.02% or less, or 0.01% or less. These impurities may include, but are not limited to, Zr, Sn, Ga, Ca, Bi, Na, Pb, or combinations thereof. Accordingly, Zr, Sn, Ga, Ca, Bi, Na, or Pb may be present in the alloy in an amount of 0.05% or less, 0.04% or less, 0.03% or less, 0.02% or less, or 0.01% or less. In some cases, the sum of all impurities does not exceed 0.15% (eg, 0.10%). all wt. expressed in %. The remaining percentage of the alloy is aluminum.

Aluminum can end and manufacturing method thereof

Also described herein are aluminum alloy articles for use, for example, as can end materials. The can end materials described herein have a substantially isotropic surface and exhibit improved formability compared to standard can end materials having an anisotropic "oriented" surface, referred to herein as a standard oriented material. The increased formability of the can end materials described herein is due, at least in part, to the increased surface isotropy compared to standard oriented materials. "Substantially" isotropic means, for the purposes of this application, to have at least 70%, at least 75%, at least 80%, at least 85%, or at least 95% isotropy.

The aluminum alloy products described herein are less prone to problems due to poor formability, such as product cracking, especially during punching operations for shell presses. Without wishing to be bound by theory, this is due, in part, to the fact that in standard oriented materials, the friction in the direction of 90° to the rolling direction is highest. In standard oriented materials, the forming load is increased due to direct intrusion of topographical peaks created with standard roll abrasive surfaces. However, in the products described herein, the number of peaks is at least 10% lower compared to standard aromatic materials. For example, the number of peaks can be lowered by at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90% as compared to a standard directional material. In some cases, no peak is present. Thus, the friction is balanced in all directions and the ultimate load due to friction in the 90° component is lowered. Moreover, when a circular product, such as a can end, is formed from standard oriented materials, the resulting shape is not a perfect circle, but is "off-drawn" into a subtle oval shape with the largest diameter in the 90° direction. This is a direct result of the higher friction in the 90° direction (and therefore higher forming load). The working window for forming can be extended to the surfaces described herein to manage the "off-drawn" phenomenon.

The surface isotropy of an aluminum alloy article may be increased by any known method, such as nanosecond laser microtexturing, discharge texturing, or rolling or transverse rolling using a modified work roll. It is not necessary to change the metallurgical properties (including orientation or anisotropy) of the central part of the aluminum alloy product resulting from the rolling production process; Rather, an advantage exists when the outer surface isotropy is increased.

Regardless of whether some residual anisotropy remains in the central portion between the top and bottom surfaces of the can end material, the treatment is improved by reducing the anisotropy at least at the top and bottom surfaces of the can end material. Thus, in some examples, the aluminum alloy article includes a thickness having a top portion, a center portion, and a bottom portion. In some instances, the top and bottom portions account for 0.1% of the thickness of the aluminum alloy article. For example, an aluminum alloy article may have a thickness of 200 μm; If the top and bottom portions occupy 1% of the thickness, they together measure 2 μm, leaving a central portion dimension of 198 μm. In some examples, the top and bottom portions occupy 0.5% of the thickness, 1% of the thickness, 5% of the thickness, 10% of the thickness, 15% of the thickness, 20% of the thickness, or 25% of the thickness. In some examples, the top and bottom portions are the same dimension; In other cases, the top and bottom portions are not the same dimension. As shown in FIG. 2 , the cross-section of the aluminum alloy product 20 includes an upper portion 21 , a central portion 22 , and a lower portion 23 .

In some examples, the aluminum alloy article has a surface percent isotropy of greater than 80% and a formability distortion of less than 10% as measured by confocal microscopy. For the purposes of this application, "surface percent isotropy" refers to the isotropy measured at the surface (top and/or bottom) of an aluminum alloy product, even though the isotropy of the aluminum alloy product varies with the thickness of the aluminum alloy product. In some examples, the aluminum alloy article comprises a surface percent isotropy of greater than 85%, greater than 90%, greater than 95%, greater than 97%, greater than 98%, greater than 99%, or 100%.

"Formability distortion" for the purposes of this application refers to maximum off-drawing when an aluminum alloy product is stamped with a circular die, such as in a shelling press, expressed as a percentage of the radius of the circle. For example, if a circle is stamped using a die having a 2.5 cm diameter, and the stamped product is a perfect 2.5 cm diameter source, the formability distortion is zero. However, if the stamped article has a radius that exceeds the intended 2.5 cm diameter at one or more points, the formability distortion is non-zero. For a maximum radius of 2.75 cm in this example, the formability distortion is 10 percent. ((2.75-2.50/2.5) = 0.10, or 10%). In some examples, the formability distortion is less than 9%, less than 8%, less than 7%, less than 6%, less than 5%, less than 4%, less than 3%, less than 2%, less than 1%, or zero. As shown in FIG. 3 , the stamped can end 30 can be drawn off from the perfect circle indicated by the dashed line. The maximum radius 31 is greater than the circle radius 32 .

The aluminum alloy articles useful in the can end material described herein may have any suitable gauge. In some examples, the aluminum alloy article may be a sheet. The sheet can be used as the can end material.

In some examples, the aluminum alloy product is a sheet, such as a can end sheet. In some examples, the aluminum alloy is a 5xxx series aluminum alloy. Suitable 5xxx series aluminum alloys are, for example, AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106, AA5010, AA5110, AA5110A, AA5210, AA5310, AA5016, AA5017, AA5018, AA501950 , AA5119A, AA5021, AA5022, AA5023, AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042, AA5043, AA5049, AA5149, AA5249, AA5349, AA5249, AA5349, AA50A AA5449, AA5050 , AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA5254, AA5354, AA5454, AA5554, AA5456, AA5659 AA54, AA5456, AA5754, AA5654A , AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA5070, AA5180, AA5180A, AA50883, 8354 83 AA 52 AA53 AA53, AA5182, AA50883, AA5182, AA50 83 , AA5086, AA5186, AA5087, AA5187, and AA5088. In some examples, the aluminum alloy includes 5182 aluminum alloy.

The anisotropy of a surface can be measured by the texture aspect ratio (Str) according to ISO 25178 as described above. The Str value is the ratio of the shortest wavelength to the longest wavelength measured in any direction with respect to the rolling direction. In some examples, the Str value for the surface of the alloy sheet described herein is greater than about 0.7. For example, the Str value can be 0.71, 0.75, 0.8, 0.85, 0.9, 0.95, 0.96, 0.97, 0.98, 0.99 or 1.0. However, conventional aluminum alloy sheets used to make can end materials typically have anisotropic surface texture. The Str value for the surface of the conventional alloy sheet is less than 0.1. The anisotropic nature of conventional can end materials can cause formability problems, such as split domes and tearing. The aluminum alloy articles useful in the can end materials described herein do not have significant anisotropy.

Examples of suitable alloys, articles, and methods

Example 1 includes a first surface having a first average surface roughness; and a second surface having a second average surface roughness, wherein the first average surface roughness is an aluminum alloy article that is at least 20% lower than the second average surface roughness as measured by a surface roughness meter.

Example 2 is the aluminum alloy of any preceding or subsequent example, wherein the first average surface roughness is at least 30% lower than the second average surface roughness.

Example 3 is the aluminum alloy of any preceding or subsequent example having a first average surface roughness of less than 0.4 μm.

Example 4 is an aluminum alloy of any preceding or subsequent example having a second average surface roughness of at least 0.4 μm.

Example 5 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy article comprises a 3xxx series aluminum alloy.

Example 6 shows that the 3xxx series aluminum alloy is an aluminum alloy of any preceding or subsequent example, including the AA3104 aluminum alloy.

Example 7 shows that the aluminum alloy product has about 0.05 - 0.25 wt. % Cu, up to about 0.8 wt. % Fe, about 0.8 - 1.3 wt. % Mg, about 0.8 - 1.4 wt. % Mn, up to about 0.6 wt. % Si, up to about 0.1 wt. % Ti, up to about 0.25 wt. % Zn, up to about 0.05 wt. % impurities, and any preceding or subsequent example aluminum alloy comprising Al.

Example 8 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy article comprises a thickness of less than about 4 mm.

Example 9 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy product is an aluminum can body.

Example 10 includes contacting the aluminum alloy article of claim 1 with a cupping press to provide a cup inner surface corresponding to the second surface and having a cup inner surface average surface roughness and a cup outer surface corresponding to the first surface and having a cup outer surface average surface roughness forming a cup comprising: wherein the cup inner surface average surface roughness is greater than the cup outer surface average surface roughness; contacting the cup inner surface with the punch sleeve and contacting the cup outer surface with the ironing die; and ironing the cup to a desired height.

Example 11 is the method of any preceding or subsequent example, wherein the cup has a wall and the method further comprises trimming the wall to form a can body, wherein the can body has a can body inner surface and a can body outer surface .

Example 12 is the method of any preceding or subsequent example wherein the cup outer surface average surface roughness is less than 0.4 μm.

Example 13 is the method of any preceding or subsequent example, wherein the cup inner surface average surface roughness is at least 0.4 μm.

Example 14 includes an aluminum can body comprising an inner surface having a can body inner surface average surface roughness and an outer surface having a can body outer surface average surface roughness, wherein the can body inner surface average surface roughness is the can body outer surface average surface roughness any preceding or subsequent example method that is at least 20% greater than

Example 15 is an aluminum alloy article comprising greater than 80% surface percent isotropy and less than 10% formability distortion as measured by confocal microscopy.

Example 16 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy article comprises greater than 95% isotropy.

Example 17 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy article comprises a 5xxx series aluminum alloy.

Example 18 is an aluminum alloy of any preceding or subsequent example wherein the 5xxx series aluminum alloy comprises a 5182 aluminum alloy.

Example 19 is the aluminum alloy of any preceding or subsequent example wherein the aluminum alloy product is an aluminum can end.

Example 20 is an aluminum alloy of any preceding or subsequent example wherein the aluminum alloy article comprises a texture aspect ratio (Str) value greater than 0.7 according to ISO 25178.

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

Claims (20)

Aluminum alloy products, including:
a first surface having a first average surface roughness; and
a second surface having a second average surface roughness, wherein the first average surface roughness is at least 20% lower than the second average surface roughness as measured by a surface roughness meter. The aluminum alloy article of claim 1 , wherein the first average surface roughness is at least 30% lower than the second average surface roughness. The aluminum alloy article according to claim 1 or 2, wherein the first average surface roughness is less than 0.4 μm. The aluminum alloy article according to claim 1 or 2, wherein the second average surface roughness is at least 0.4 μm. 5. The aluminum alloy article according to any one of the preceding claims, wherein the aluminum alloy article comprises a 3xxx series aluminum alloy. 6. The aluminum alloy article of claim 5, wherein the 3xxx series aluminum alloy comprises AA3104 aluminum alloy. 7. The aluminum alloy product according to any one of claims 1 to 6, wherein the aluminum alloy product comprises 0.05 - 0.25 wt. % Cu, up to 0.8 wt. % Fe, 0.8 - 1.3 wt. % Mg, 0.8 - 1.4 wt. % Mn, up to 0.6 wt. % Si, up to 0.1 wt. % Ti, up to 0.25 wt. % Zn, max. 0.05 wt. % impurities, and aluminum alloy products comprising Al. 8. The aluminum alloy article of any one of claims 1-7, wherein the aluminum alloy article comprises a thickness of less than about 4 mm. 9. The aluminum alloy article according to any one of claims 1 to 8, wherein the aluminum alloy article is an aluminum can body. A method of manufacturing an aluminum can body, comprising the steps of:
10. Contacting the aluminum alloy product of any one of claims 1 to 9 with a cupping press, the cup inner surface corresponding to the second surface and having the cup inner surface average surface roughness and the first surface corresponding to the cup outer surface average surface roughness forming a cup comprising a cup outer surface having a cup inner surface average surface roughness greater than the cup outer surface average surface roughness;
contacting the cup inner surface with the punch sleeve and contacting the cup outer surface with the ironing die; and
Ironing the cup to the desired height. The method of claim 10 , wherein the cup has a wall and the method further comprises trimming the wall to form a can body, wherein the can body has a can body inner surface and a can body outer surface. 12. The method of claim 10 or 11, wherein the cup outer surface average surface roughness is less than 0.4 μm. 12. The method according to claim 10 or 11, wherein the cup inner surface average surface roughness is at least 0.4 μm. 14. The aluminum can body according to any one of claims 11 to 13, wherein the aluminum can body comprises an inner surface having a can body inner surface average surface roughness and an outer surface having a can body outer surface average surface roughness, wherein the can body inner surface How the average surface roughness is at least 20% greater than the average surface roughness of the outer surface of the can body. An aluminum alloy article comprising greater than 80% surface percent isotropy and less than 10% formability distortion as measured by confocal microscopy. The aluminum alloy article of claim 15 , wherein the aluminum alloy article comprises greater than 95% isotropy. 17. The aluminum alloy article of claim 15 or 16, wherein the aluminum alloy article comprises a 5xxx series aluminum alloy. 18. The aluminum alloy article of claim 17, wherein the 5xxx series aluminum alloy comprises 5182 aluminum alloy. 19. An aluminum alloy article according to any one of claims 15 to 18, wherein the aluminum alloy article is an aluminum can end. 20. The aluminum alloy article of any of claims 15-19, wherein the aluminum alloy article comprises a Texture Aspect Ratio (Str) value of greater than 0.7 according to ISO 25178.

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