U.S. patent application number 16/428137 was filed with the patent office on 2019-12-05 for low gauge, levelled can body stock and methods of making the same.
The applicant listed for this patent is Novelis Inc.. Invention is credited to Ian Musson Campbell, Thomas Wuttke.
Application Number | 20190368020 16/428137 |
Document ID | / |
Family ID | 66867865 |
Filed Date | 2019-12-05 |
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United States Patent
Application |
20190368020 |
Kind Code |
A1 |
Campbell; Ian Musson ; et
al. |
December 5, 2019 |
LOW GAUGE, LEVELLED CAN BODY STOCK AND METHODS OF MAKING THE
SAME
Abstract
Described herein are levelled and degreased aluminum alloys with
a reduced gauge for can body stock production. The aluminum alloys
exhibit improved formability. Also described herein are methods for
processing the aluminum alloys to produce beverage can bodies. The
aluminum alloys and sheets described herein are suitable for
manufacturing cups and beverage can bodies at high production
rates.
Inventors: |
Campbell; Ian Musson;
(Gottingen, DE) ; Wuttke; Thomas; (Renshausen,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novelis Inc. |
Atlanta |
GA |
US |
|
|
Family ID: |
66867865 |
Appl. No.: |
16/428137 |
Filed: |
May 31, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62679222 |
Jun 1, 2018 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C22F 1/04 20130101; B22D
21/007 20130101; C22C 21/08 20130101; C22C 21/00 20130101; C22F
1/047 20130101 |
International
Class: |
C22F 1/047 20060101
C22F001/047; C22C 21/08 20060101 C22C021/08; B22D 21/00 20060101
B22D021/00 |
Claims
1. A method of producing an aluminum alloy product, comprising:
casting an aluminum alloy comprising about 0.05-0.4 wt. % Cu,
0.25-0.9 wt. % Fe, 0.8-3.0 wt. % Mg, 0.1-2.0 wt. % Mn, 0.2-0.7 wt.
% Si, up to 0.1 wt. % Ti, up to 0.25 wt. % Zn, up to 0.4 wt. % Cr,
up to 0.15 wt. % impurities, and Al, to form a cast aluminum alloy;
heating the cast aluminum alloy; hot rolling the cast aluminum
alloy to produce a rolled product; cold rolling the rolled product
to produce an aluminum alloy product; and levelling the aluminum
alloy product.
2. The method of claim 1, wherein casting is performed by
semi-continuous direct chill ingot casting or strip casting.
3. The method of claim 1, wherein heating the cast aluminum alloy
comprises homogenizing the cast aluminum alloy.
4. The method of claim 1, further comprising degreasing the
aluminum alloy product.
5. The method of claim 1, further comprising removing aluminum
fines, rolling oil, and debris from the aluminum alloy product.
6. The method of claim 1, further comprising lubricating the
aluminum alloy product with a cupping lubricant.
7. An aluminum alloy product prepared according to the method of
claim 1.
8. The aluminum alloy product of claim 7, wherein the aluminum
alloy comprises a 3xxx series or 5xxx series aluminum alloy.
9. The aluminum alloy product of claim 7, wherein the aluminum
alloy product is a sheet.
10. The aluminum alloy product of claim 9, wherein the sheet has a
longitudinal yield strength of at least about 260 MPa.
11. The aluminum alloy product of claim 9, wherein the sheet is
thermally-levelled at a temperature ranging from about 170.degree.
C. to about 280.degree. C.
12. The aluminum alloy product of claim 9, wherein the sheet is
tension-levelled in a longitudinal direction.
13. The aluminum alloy product of claim 7, wherein the aluminum
alloy product comprises a thickness of less than about 240
.mu.m.
14. The aluminum alloy product of claim 7, wherein one or more
surfaces of the aluminum alloy product has a texture aspect ratio
of 0.1 to 0.7.
15. The aluminum alloy product of claim 7, wherein one or more
surfaces of the aluminum alloy product comprise cupping lubricant
in an amount at least about 200 mg of per square meter per side
(mg/m.sup.2/side).
16. The aluminum alloy product of claim 7, wherein the one or more
surfaces of the aluminum alloy product comprise a post-lubricant in
an amount of from about 5 mg/m.sup.2/side to about 100
mg/m.sup.2/side.
17. The aluminum alloy product of claim 16, wherein the
post-lubricant comprises dibutyl adipate, dibutyl sebacate, dihexyl
adipate, dihexyl sebacate, dicyclohexyl adipate, dicyclohexyl
sebacate, dioctyl adipate, dioctyl sebacate, diisodecyl adipate,
diisodecyl sebacate, diundecyl adipate, diundecyl sebacate,
didodecanyl adipate, didodecanyl sebacate, diphenyl sebacate, or
diphenyl adipate.
18. The aluminum alloy product of claim 7, wherein the aluminum
alloy product is substantially free of aluminum fines and
debris.
19. The aluminum alloy product of claim 7, wherein the aluminum
alloy product comprises a beverage can body.
20. An aluminum alloy product, comprising: an aluminum alloy
comprising about 0.05-0.4 wt. % Cu, 0.25-0.9 wt. % Fe, 0.8-3.0 wt.
% Mg, 0.1-2.0 wt. % Mn, 0.2-0.7 wt. % Si, up to 0.1 wt. % Ti, up to
0.25 wt. % Zn, up to 0.4 wt. % Cr, up to 0.15 wt. % impurities, and
Al, wherein the aluminum alloy product comprises a thickness of
less than about 240 .mu.m.
21. The aluminum alloy product of claim 20, wherein one or more
surfaces of the aluminum alloy product has a texture aspect ratio
of 0.1 to 0.7.
Description
PRIORITY
[0001] This application claims priority to and filing benefit of
U.S. provisional application Ser. No. 62/679,222 filed Jun. 1,
2018, which is incorporated herein by reference in its
entirety.
FIELD
[0002] The present disclosure is directed to aluminum alloy
products and the properties of the same. The disclosure further
relates to can body stock and methods of producing and processing
the same.
BACKGROUND
[0003] Metal cans are well known and widely used as beverage
containers. Conventional beverage can bodies are generally made
from metal at least 240 .mu.m in thickness, which is considered to
be necessary to achieve the strength requirements for can bodies.
Beverage can bodies are manufactured at high production rates and
there is an ever-increasing demand to reduce metal content, and
therefore cost, of the beverage can by down-gauging. There are also
demands to further increase the production rate of beverage cans by
eliminating metal-related jams at the cupper press and tear-offs
and split domes at the bodymakers. However, the inherent
non-flatness of cold-rolled aluminum sheets, insufficient surface
lubricity, presence of surface fines and residual rolling oil, and
formability properties of existing aluminum can body stock can
prevent successful reduction in metal content (light-weighting) and
can cause a reduction in productivity rates for can body
production.
SUMMARY
[0004] Covered embodiments of the invention are defined by the
claims, not this summary. This summary is a high-level overview of
various aspects of the invention and introduces some of the
concepts that are further described in the Detailed Description
section below. This summary is not intended to identify key or
essential features of the claimed subject matter, nor is it
intended to be used in isolation to determine the scope of the
claimed subject matter. The subject matter should be understood by
reference to appropriate portions of the entire specification, any
or all drawings, and each claim.
[0005] Described herein is a method of producing an aluminum alloy
product, such as an aluminum alloy sheet for use as can body stock.
The method comprises casting an aluminum alloy comprising about
0.05-0.4 wt. % Cu, 0.25-0.9 wt. % Fe, 0.8-3.0 wt. % Mg, 0.1-2.0 wt.
% Mn, 0.2-0.7 wt. % Si, up to 0.1 wt. % Ti, up to 0.25 wt. % Zn, up
to 0.4 wt. % Cr, up to 0.15 wt. % impurities, and Al, to form a
cast aluminum alloy; heating the cast aluminum alloy; hot rolling
the cast aluminum alloy to produce a rolled product; cold rolling
the rolled product to produce an aluminum alloy product; and
levelling the aluminum alloy product. Optionally, the casting can
be performed by semi-continuous direct chill ingot casting or strip
casting. In some cases, the step of heating the cast aluminum
comprises homogenizing the cast aluminum alloy. The method can
further comprise degreasing the aluminum alloy product, removing
aluminum fines, rolling oil, and debris from the aluminum alloy
product, and/or lubricating the aluminum alloy product with a
cupping lubricant. In some cases, the degreasing process comprises
use of a solvent or hot water.
[0006] Also described herein is an aluminum alloy product prepared
according to the method described herein. The aluminum alloy can
comprise a 3xxx series aluminum alloy or a 5xxx series aluminum
alloy. In some cases, the aluminum alloy comprises about 0.05-0.3
wt. % Cu, 0.4-0.8 wt. % Fe, 0.8-2.8 wt. % Mg, 0.1-1.5 wt. % Mn,
0.25-0.6 wt. % Si, up to 0.1 wt. % Ti, 0.1-0.25 wt. % Zn, up to
0.35 wt. % Cr, up to 0.15 wt. % impurities, and Al.
[0007] The aluminum alloy product can be a sheet. In some cases,
the aluminum alloy product comprises a thickness of less than about
240 .mu.m (e.g., from about 170 .mu.m to less than about 240 .mu.m
or from about 180 .mu.m to about 230 .mu.m). The sheet can have a
longitudinal yield strength of at least about 260 MPa (e.g., from
about 260 MPa to about 300 MPa). Optionally, one or more surfaces
of the aluminum alloy product comprise an isotropic surface
texture. The one or more surfaces of the aluminum alloy product can
optionally have a texture aspect ratio of 0.1 to 0.7. In some
cases, one or more surfaces of the aluminum alloy product comprise
at least about 200 mg/m.sup.2 of cupping lubricant per side
(mg/m.sup.2/side) (e.g., from about 200 mg/m.sup.2/side to about
1000 mg/m.sup.2/side or from about 500 mg/m.sup.2/side to about 800
mg/m.sup.2/side). Optionally, one or more surfaces of the aluminum
alloy product comprise a post-lubricant in an amount of from about
5 mg/m.sup.2/side to about 100 mg/m.sup.2/side (e.g., from about 10
mg/m.sup.2/side to about 25 mg/m.sup.2/side or from about 20
mg/m.sup.2/side to about 50 mg/m.sup.2/side). In some cases, the
post-lubricant can include dibutyl adipate, dibutyl sebacate,
dihexyl adipate, dihexyl sebacate, dicyclohexyl adipate,
dicyclohexyl sebacate, dioctyl adipate, dioctyl sebacate,
diisodecyl adipate, diisodecyl sebacate, diundecyl adipate,
diundecyl sebacate, didodecanyl adipate, didodecanyl sebacate,
diphenyl sebacate, diphenyl adipate, or mixtures of these.
Optionally, the levelling of the aluminum alloy product is
performed in a longitudinal direction. The levelling can be
performed such that residual stresses from cold-rolling are
reduced, which results in a much flatter product. In some cases,
the aluminum alloy product is substantially free of aluminum fines,
rolling oil, and surface debris from the rolling process. The
aluminum alloy product can comprise a beverage can body.
[0008] Further described herein is an aluminum alloy product
comprising an aluminum alloy comprising about 0.05-0.4 wt. % Cu,
0.25-0.9 wt. % Fe, 0.8-3.0 wt. % Mg, 0.1-2.0 wt. % Mn, 0.2-0.7 wt.
% Si, up to 0.1 wt. % Ti, up to 0.25 wt. % Zn, up to 0.4 wt. % Cr,
up to 0.15 wt. % impurities, and Al, wherein the aluminum alloy
product comprises a thickness of less than about 240 .mu.m (e.g.,
from about 170 .mu.m to less than about 240 .mu.m or from about 180
.mu.m to about 230 .mu.m). Optionally, the aluminum alloy comprises
about 0.05-0.3 wt. % Cu, 0.4-0.8 wt. % Fe, 0.8-2.8 wt. % Mg,
0.1-1.5 wt. % Mn, 0.25-0.6 wt. % Si, up to 0.1 wt. % Ti, 0.1-0.25
wt. % Zn, up to 0.35 wt. % Cr, up to 0.15 wt. % impurities, and Al.
In some cases, one or more surfaces of the aluminum alloy product
has a texture aspect ratio of 0.1 to 0.7. Other objects and
advantages of the invention will be apparent from the following
detailed description of non-limiting examples.
BRIEF DESCRIPTION OF THE FIGURES
[0009] FIG. 1 is a chart of yield strength with respect to soaking
time for different soaking temperatures according to one example of
the present disclosure.
[0010] FIG. 2 is a chart of ultimate tensile strength with respect
to soaking time for different soaking temperatures according to one
example of the present disclosure.
[0011] FIG. 3 is a chart of spread with respect to soaking time for
different soaking temperatures according to one example of the
present disclosure.
[0012] FIG. 4 is a chart of total elongation with respect to
soaking time for different soaking temperatures according to one
example of the present disclosure.
[0013] FIG. 5 is a chart of yield stress with respect to soaking
time for different soaking temperatures according to one example of
the present disclosure.
DETAILED DESCRIPTION
[0014] Described herein are reduced gauge aluminum alloys with
improved formability, products including the aluminum alloys, and
methods for making the products. The aluminum alloy compositions
and methods described herein provide an improved aluminum alloy
sheet for the efficient production of products, such as aluminum
beverage can bodies, in both raw material usage and production
rate. For example, the aluminum alloy sheets described herein have
a reduced gauge (e.g., from about 180 .mu.m to about 240 .mu.m) as
compared to conventional aluminum alloy sheets used for can bodies,
and, in turn, a reduced amount of aluminum in each beverage can.
The can bodies prepared from the aluminum alloy sheets described
herein meet the desired strength properties for beverage cans at
this reduced gauge.
[0015] Additionally, the aluminum alloy sheets described herein
have an isotropic surface texture. The anisotropy of the surface
can be measured by the Texture Aspect Ratio (Str), according to ISO
25178. The Str value is the ratio of the shortest wavelength to the
longest wavelength measured in any direction relative to the
rolling direction. In some examples, the Str value for the surface
of alloy sheet as described herein is from about 0.1 to about 0.7.
For example, the Str value can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, or
0.7. Conventional aluminum alloy sheets used to prepare can body
stock, however, typically have an anisotropic surface texture.
[0016] The Str value for the surface of a conventional alloy sheet
is less than 0.1. The anisotropic nature of conventional can body
stock can cause formability issues, such as split domes and tear
offs. The aluminum alloy products described herein are free of
significant anisotropy.
[0017] Further, the aluminum alloy sheets described herein can be
used for the more efficient production of can bodies as compared to
conventional can body stock prepared according to conventional
methods. Conventional can body stock contains a high level of
surface debris from hot rolling and cold rolling. Such debris
causes a buildup of fines on the cupper tooling and additional
tool-wear and also causes the need for frequent cleaning of the
bodymaker coolant. According to some methods as described herein,
the aluminum alloy sheets for use as the can body stock are
degreased, levelled, and/or lubricated with a suitable lubricant,
which enables a cupping press to efficiently operate at high
speeds. For example, a cupping press can process the aluminum alloy
sheets as described herein at speeds ranging from 200 to 500
strokes per minute (spm) without significant feeding issues and
without need for the application of an additional cupper
lubricant.
Definitions and Descriptions
[0018] The terms "invention," "the invention," "this invention,"
and "the present invention" used herein are intended to refer
broadly to all of the subject matter of this patent application and
the claims below. Statements containing these terms should be
understood not to limit the subject matter described herein or to
limit the meaning or scope of the patent claims below. In this
description, reference is made to alloys identified by aluminum
industry designations, such as "series" or "3xxx." For an
understanding of the number designation system most commonly used
in naming and identifying aluminum and its alloys, see
"International Alloy Designations and Chemical Composition Limits
for Wrought Aluminum and Wrought Aluminum Alloys" or "Registration
Record of Aluminum Association Alloy Designations and Chemical
Compositions Limits for Aluminum Alloys in the Form of Castings and
Ingot," both published by The Aluminum Association.
[0019] As used herein, the meaning of "a," "an," or "the" includes
singular and plural references unless the context clearly dictates
otherwise.
[0020] As used herein, a plate generally has a thickness of greater
than about 15 mm. For example, a plate may refer to an aluminum
product having a thickness of greater than about 15 mm, greater
than about 20 mm, greater than about 25 mm, greater than about 30
mm, greater than about 35 mm, greater than about 40 mm, greater
than about 45 mm, greater than about 50 mm, or greater than about
100 mm.
[0021] As used herein, a shate (also referred to as a sheet plate)
generally has a thickness of from about 4 mm to about 15 mm. For
example, a shate may have a thickness of about 4 mm, about 5 mm,
about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about
11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm.
[0022] As used herein, a sheet generally refers to an aluminum
product having a thickness of less than about 4 mm. For example, a
sheet may have a thickness of less than about 4 mm, less than about
3 mm, less than about 2 mm, less than about 1 mm, less than about
0.5 mm, less than about 0.3 mm, or less than about 0.1 mm.
[0023] As used herein, terms such as "cast metal product," "cast
product," "cast aluminum alloy product," and the like are
interchangeable and refer to a product produced by direct chill
casting (including direct chill co-casting) or semi-continuous
casting, continuous casting (including, for example, by use of a
twin belt caster, a twin roll caster, a block caster, or any other
continuous caster), electromagnetic casting, hot top casting, or
any other casting method.
[0024] All ranges disclosed herein are to be understood to
encompass any and all subranges subsumed therein. For example, a
stated range of "1 to 10" should be considered to include any and
all subranges between (and inclusive of) the minimum value of 1 and
the maximum value of 10; that is, all subranges beginning with a
minimum value of 1 or more, e.g., 1 to 6.1, and ending with a
maximum value of 10 or less, e.g., 5.5 to 10.
[0025] The following aluminum alloys are described in terms of
their elemental composition in weight percentage (wt. %) based on
the total weight of the alloy. In certain examples of each alloy,
the remainder is aluminum, with a maximum wt. % of 0.15% for the
sum of the impurities.
Aluminum Alloys and Products
[0026] Described herein are aluminum alloys, products prepared from
the same, and methods of preparing the aluminum alloys and
products. Products described herein include, for example, reduced
gauge sheets having an isotropic surface texture. Such products can
be used, for example, as can body stock. Specifically, the aluminum
alloy products described herein, having a gauge of lower than about
240 .mu.m, exhibit the strength of conventional aluminum alloy can
body stock having a 240 .mu.m gauge or greater. The aluminum alloy
products described herein are advantageously levelled to produce a
relatively flat sheet, which enables the efficient use of the
aluminum alloy products in a cupping press at high speeds. The
reduced gauge aluminum alloy sheets can display longitudinal yield
strengths of 260 MPa and higher. In addition, the aluminum alloy
products described herein exhibit exceptional surface qualities
which result in a visually brighter aluminum can. The aluminum
alloy products also exhibit excellent lubricity such that no
additional lubricant is needed prior to cupping. Additionally, the
aluminum fines, surface debris, and rolling oil are removed from
the aluminum alloy product, reducing potential contamination to the
cupping and bodymaker presses. As a result of the levelled and
lubricated surfaces of the products disclosed herein, the downtime
on cupping lines can be greatly reduced, thereby resulting in a
significant improvement in production rates and decreased operating
costs.
[0027] Furthermore, due to the isotropic rolled surface, the
surface friction and distribution of the lubricant is no longer
dependent on the rolling direction. A more directionally uniform
topography therefore enhances the drawing, wall-ironing, and
dome-forming capabilities in the bodymaker operation (e.g., fewer
punch-throughs, tear-offs, split (or "open") domes as well as
inhibiting the tendency to "bleedthrough").
[0028] Additionally, the aluminum alloy products as described
herein can be advanced on a cupping line without the use of
lubrication and feed rolls that may cause surface damage or stress
deformation in the product. By utilizing the Lenz effect, the
aluminum alloy product can be advanced on a cupping line by
rotating a magnet to induce a current and magnetic field. Use of
the Lenz effect thereby eliminates the potential stress
deformations and/or surface defects from traditional compression
and pinch rolls.
[0029] Aluminum alloys for use in the products and methods
described herein include 3xxx series aluminum alloys and 5xxx
series aluminum alloys. Suitable 3xxx series aluminum alloys
include, for example, AA3002, AA3102, AA3003, AA3103, AA3103A,
AA3103B, AA3203, AA3403, AA3004, AA3004A, AA3104, AA3204, AA3304,
AA3005, AA3005A, AA3105, AA3105A, AA3105B, AA3007, AA3107, AA3207,
AA3207A, AA3307, AA3009, AA3010, AA3110, AA3011, AA3012, AA3012A,
AA3013, AA3014, AA3015, AA3016, AA3017, AA3019, AA3020, AA3021,
AA3025, AA3026, AA3030, AA3130, and AA3065.
[0030] Suitable 5xxx series aluminum alloys include, for example,
AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106,
AA5010, AA5110, AA5110A, AA5210, AA5310, AA5016, AA5017, AA5018,
AA5018A, AA5019, AA5019A, AA5119, AA5119A, AA5021, AA5022, AA5023,
AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042,
AA5043, AA5049, AA5149, AA5249, AA5349, AA5449, AA5449A, AA5050,
AA5050A, AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A,
AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B,
AA5154C, AA5254, AA5354, AA5454, AA5554, AA5654, AA5654A, AA5754,
AA5854, AA5954, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B,
AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657,
AA5058, AA5059, AA5070, AA5180, AA5180A, AA5082, AA5182, AA5083,
AA5183, AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086,
AA5186, AA5087, AA5187, and AA5088.
[0031] In some examples, the alloys for use in the products and
methods described herein can have the following elemental
composition as provided in Table 1.
TABLE-US-00001 TABLE 1 Element Weight Percentage (wt. %) Cu
0.05-0.4 Fe 0.25-0.9 Mg 0.8-3.0 Mn 0.1-2.0 Si 0.2-0.7 Ti 0-0.1 Zn
0-0.25 Cr 0-0.4 Others 0-0.05 (each) 0-0.15 (total) Al
Remainder
[0032] In some examples, the alloy can have the following elemental
composition as provided in Table 2.
TABLE-US-00002 TABLE 2 Element Weight Percentage (wt. %) Cu
0.05-0.3 Fe 0.4-0.8 Mg 0.8-2.8 Mn 0.1-1.5 Si 0.25-0.6 Ti 0-0.1 Zn
0.1-0.25 Cr 0-0.35 Others 0-0.05 (each) 0-0.15 (total) Al
Remainder
[0033] In some examples, the alloys described herein include copper
(Cu) in an amount of 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. For example, the alloy can
include 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 are expressed in wt. %.
[0034] In some examples, the alloys described herein include iron
(Fe) in an amount of from about 0.25% 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. For example, the alloy can
include 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. All are expressed in wt. %.
[0035] In some examples, the alloys described herein include
magnesium (Mg) in an amount of 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%)
based on the total weight of the alloy. For example, the alloy can
include 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 are expressed in wt. %.
[0036] In some examples, the alloys described herein include
manganese (Mn) in an amount of 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%)
based on the total weight of the alloy. For example, the alloy can
include 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 are expressed in wt. %.
[0037] In some examples, the alloys described herein include
silicon (Si) in an amount of from about 0.2% 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. For example, the alloy can
include 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. All are
expressed in wt. %.
[0038] In some examples, the alloys described herein include
titanium (Ti) in an amount 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. For example, the alloy can include
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 (i.e., 0%).
All are expressed in wt. %.
[0039] In some examples, the alloys described herein include zinc
(Zn) in an amount 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. For example, the alloy can include 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 (i.e., 0%). All are expressed in wt.
%.
[0040] In some examples, the alloys described herein include
chromium (Cr) in an amount 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. For example, the alloy can include
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 (i.e., 0%). All are expressed in wt. %.
[0041] Optionally, the alloy compositions described herein can
further include other minor elements, sometimes referred to as
impurities, in amounts of 0.05% or below, 0.04% or below, 0.03% or
below, 0.02% or below, or 0.01% or below. 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 alloys in amounts of 0.05% or below, 0.04% or
below, 0.03% or below, 0.02% or below or 0.01% or below. In some
cases, the sum of all impurities does not exceed 0.15% (e.g.,
0.10%). All are expressed in wt. %. The remaining percentage of the
alloy is aluminum.
[0042] Various products including the aluminum alloys described
herein can be produced. The aluminum alloy products described
herein can have any suitable gauge. In some examples, the aluminum
alloy product can be a sheet. Optionally, the sheet gauge is less
than about 240 .mu.m (e.g., from about 170 .mu.m to less than about
240 .mu.m, from about 180 .mu.m to about 230 .mu.m, or from about
190 .mu.m to about 220 .mu.m). For example, the sheet can have a
gauge of about 170 .mu.m, 175 .mu.m, 180 .mu.m, 185 .mu.m, 190
.mu.m, 195 .mu.m, 200 .mu.m, 205 .mu.m, 210 .mu.m, 215 .mu.m, 220
.mu.m, 225 .mu.m, 230 .mu.m, 235 .mu.m, or 240 .mu.m. The sheet can
be used as can body stock.
Aluminum Alloy Product Properties
[0043] The aluminum alloy products as described herein have a
combination of desired properties, including suitable strength and
high formability. The aluminum alloy products can exhibit a
longitudinal yield strength of at least about 260 MPa (e.g., from
about 260 MPa to about 300 MPa). For example, the longitudinal
yield strength can be at least about 260 MPa, at least about 265
MPa, at least about 270 MPa, at least about 275 MPa, at least about
280 MPa, at least about 285 MPa, at least 290 MPa, at least about
295 MPa, or at least about 300 MPa.
[0044] In some examples, the aluminum alloy products are
substantially uniform, with few areas of non-uniformity.
Optionally, the aluminum alloy products can be levelled, as
explained in further detail below, to reduce residual stress and
cold-rolled to generate an isotropic surface texture. In some
examples, an aluminum alloy product is tension-levelled in a
longitudinal direction. In some examples, an aluminum alloy product
is thermally-levelled. Optionally, the levelling of the aluminum
alloy product, such as an aluminum alloy strip, can be measured on
a flatness table with a resolution of 2 mm in the x- and
y-directions. The flatness of the levelled sheet can be measured in
I-units. In some cases, the height and length of the deviations
(i.e., non-flat areas) can be measured and the I-unit can be
calculated by the following formula:
I-unit=(DL/L).times.10.sup.5 units (1)
wherein DL is deviation in length and L is the segment length of
the levelled sheet. In some examples, the levelled sheet can have
an I-value of about 50 or less (e.g., about 45 or less, about 40 or
less, about 35 or less, about 30 or less, about 25 or less, about
20 or less, about 15 or less, about 10 or less, or about 5 or
less).
[0045] In some examples, one or more surfaces of the aluminum alloy
products are substantially free of rolling lubricant, aluminum
fines, and debris. As used herein, the term "substantially free of
rolling lubricant, aluminum fines, and debris" means that the one
or more surfaces of the aluminum alloy products can include less
than about 1%, less than about 0.1%, less than about 0.01%, less
than about 0.001%, less than about 0.0001%, or 0% of the component
(e.g., rolling lubricant, aluminum fines, and/or debris) per square
millimeter (mm.sup.2) of the aluminum alloy product surface. In
some examples, the aluminum alloy products contain cupping
lubricant on one or more surfaces for use in downstream processing,
such as in a cupping process. In some cases, one or more surfaces
of the aluminum alloy products have at least about 200 mg of
cupping lubricant per square meter (m.sup.2) per side (e.g., from
about 200 mg/m.sup.2 to about 1000 mg/m.sup.2 or from about 500
mg/m.sup.2 to about 800 mg/m.sup.2 cupping lubricant per side). For
example, one or more surfaces of the aluminum alloy products can
have about 200 mg/m.sup.2, about 250 mg/m.sup.2, about 300
mg/m.sup.2, about 350 mg/m.sup.2, about 400 mg/m.sup.2, about 450
mg/m.sup.2, about 500 mg/m.sup.2, about 550 mg/m.sup.2, about 600
mg/m.sup.2, about 650 mg/m.sup.2, about 700 mg/m.sup.2, about 750
mg/m.sup.2, about 800 mg/m.sup.2, about 850 mg/m.sup.2, about 900
mg/m.sup.2, about 950 mg/m.sup.2, or about 1000 mg/m.sup.2 cupping
lubricant per side. The lubricant can eliminate the need for an
additional lubricant for production of beverage can bodies.
[0046] In some cases, the aluminum alloy products contain
post-lubricant on one or more surfaces to help inhibit corrosion
related to moisture in the atmosphere and fretting corrosion due to
interlap movement during transportation and unwinding. In some
cases, one or more surfaces of the aluminum alloy products have at
least about 5 mg of post-lubricant per square meter (m.sup.2) per
side (e.g., from about 5 mg/m.sup.2 to about 100 mg/m.sup.2 or from
about 25 mg/m.sup.2 to about 75 mg/m.sup.2 post-lubricant per
side). For example, one or more surfaces of the aluminum alloy
products can have about 5 mg/m.sup.2, about 10 mg/m.sup.2, about 15
mg/m.sup.2, about 20 mg/m.sup.2, about 25 mg/m.sup.2, about 30
mg/m.sup.2, about 35 mg/m.sup.2, about 40 mg/m.sup.2, about 45
mg/m.sup.2, about 50 mg/m.sup.2, about 55 mg/m.sup.2, about 60
mg/m.sup.2, about 65 mg/m.sup.2, about 70 mg/m.sup.2, about 75
mg/m.sup.2, about 80 mg/m.sup.2, about 85 mg/m.sup.2, about 90
mg/m.sup.2, about 95 mg/m.sup.2, or about 100 mg/m.sup.2
post-lubricant per side. In some cases, the post-lubricant can
include one or more of dibutyl adipate, dibutyl sebacate, dihexyl
adipate, dihexyl sebacate, dicyclohexyl adipate, dicyclohexyl
sebacate, dioctyl adipate, dioctyl sebacate, diisodecyl adipate,
diisodecyl sebacate, diundecyl adipate, diundecyl sebacate,
didodecanyl adipate, didodecanyl sebacate, diphenyl sebacate, or
diphenyl adipate.
Methods of Making
[0047] The aluminum alloys described above can be cast into a cast
product. The alloys can be cast using any casting process performed
according to standards commonly used in the aluminum industry as
known to one of ordinary skill in the art. For example, the alloys
may be cast using a continuous casting (CC) process that may
include, but is not limited to, the use of twin belt casters, twin
roll casters, or block casters. In some examples, the casting
process is performed by a CC process to form a cast product such as
a billet, slab, shate, strip, or the like. In some examples, the
casting process is performed by a Direct Chill (DC) casting process
to form a cast product such as an ingot. In some examples, the
casting process is performed by strip casting. The cast product can
then be subjected to further processing steps. Such processing
steps include, but are not limited to, a heating step, a hot
rolling step, a cold rolling step, and/or an annealing step.
Optionally, the heating step can include homogenizing the cast
aluminum alloy. Optionally, the sheet can be further processed
using a degreasing step, a levelling step, and/or a lubricating
step.
[0048] Heating
[0049] The heating step can include heating a cast aluminum alloy
product, such as an ingot, prepared from an aluminum alloy
composition described herein to attain a peak metal temperature
(PMT) of about, or at least about, 450.degree. C. (e.g., at least
about 460.degree. C., at least about 470.degree. C., at least about
480.degree. C., at least about 490.degree. C., at least about
500.degree. C., at least about 510.degree. C., at least about
520.degree. C., at least about 530.degree. C., at least about
540.degree. C., at least about 550.degree. C., at least about
560.degree. C., at least about 570.degree. C., or at least about
580.degree. C.). For example, the cast aluminum alloy product can
be heated to a temperature of from about 450.degree. C. to about
580.degree. C., from about 460.degree. C. to about 575.degree. C.,
from about 470.degree. C. to about 570.degree. C., from about
480.degree. C. to about 565.degree. C., from about 490.degree. C.
to about 555.degree. C., or from about 500.degree. C. to about
550.degree. C. In some cases, the heating rate to the PMT can be
about 100.degree. C./hour or less, 75.degree. C./hour or less,
50.degree. C./hour or less, 40.degree. C./hour or less, 30.degree.
C./hour or less, 25.degree. C./hour or less, 20.degree. C./hour or
less, or 15.degree. C./hour or less. In other cases, the heating
rate to the PMT can be from about 10.degree. C./min to about
100.degree. C./min (e.g., from about 10.degree. C./min to about
90.degree. C./min, from about 10.degree. C./min to about 70.degree.
C./min, from about 10.degree. C./min to about 60.degree. C./min,
from about 20.degree. C./min to about 90.degree. C./min, from about
30.degree. C./min to about 80.degree. C./min, from about 40.degree.
C./min to about 70.degree. C./min, or from about 50.degree. C./min
to about 60.degree. C./min).
[0050] In some cases, the heating step includes homogenizing the
cast aluminum alloy where the cast aluminum alloy product is
allowed to soak (i.e., held at the indicated temperature) for a
period of time. In some cases, the cast aluminum alloy product is
allowed to soak for at least 30 minutes at a peak metal temperature
as described above. According to one non-limiting example, the cast
aluminum alloy product is allowed to soak for up to about 36 hours
(e.g., from about 30 minutes to about 36 hours, inclusively). For
example, the cast aluminum alloy product can be soaked at the peak
metal temperature for 30 minutes, 1 hour, 2 hours, 3 hours, 4
hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11
hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours,
18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24
hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, 30 hours,
31 hours, 32 hours, 33 hours, 34 hours, 35 hours, 36 hours, or
anywhere in between.
[0051] Hot Rolling and Cold Rolling
[0052] Following the homogenization step, a hot rolling step can be
performed. The hot rolling step can include a hot reversing mill
operation and/or a hot tandem mill operation. The hot rolling step
can be performed at a temperature ranging from about 250.degree. C.
to about 550.degree. C. (e.g., from about 300.degree. C. to about
500.degree. C. or from about 350.degree. C. to about 450.degree.
C.).
[0053] A cold rolling step can optionally be applied to form an
aluminum alloy product. For example, the cast aluminum alloy
product can be cold rolled to a thickness of less than about 4 mm.
In some examples, a sheet can have a thickness of less than 4 mm,
less than 3 mm, less than 2 mm, less than 1 mm, less than 0.9 mm,
less than 0.8 mm, less than 0.7 mm, less than 0.6 mm, less than 0.5
mm, less than 0.4 mm, less than 0.3 mm, less than 0.2 mm, or less
than 0.1 mm. Optionally, the sheet gauge is less than about 240
.mu.m (e.g., from about 170 .mu.m to less than about 240 .mu.m,
from about 180 .mu.m to about 230 .mu.m, or from about 190 .mu.m to
about 220 .mu.m). For example, the sheet can have a gauge of about
170 .mu.m, 175 .mu.m, 180 .mu.m, 185 .mu.m, 190 .mu.m, 195 .mu.m,
200 .mu.m, 205 .mu.m, 210 .mu.m, 215 .mu.m, 220 .mu.m, 225 .mu.m,
230 .mu.m, 235 .mu.m, or 240 .mu.m. The sheet can be used as can
body stock.
[0054] Degreasing
[0055] The process described herein can optionally include at least
one degreasing step applied to the aluminum alloy product. The term
"degreasing," as used herein, includes processing the aluminum
alloy product to remove residual oil accumulated on the surface
from the hot rolling and cold rolling processes. The degreasing
step can also remove residual surface debris, rolling oil, and
aluminum fines from the rolling processes. The degreased surface
gives an improved surface appearance to the can body and reduces
the build-up of fines during the cupping process. The degreasing
agent for use in the degreasing step can include water and/or
solvents. Optionally, the water for use in the degreasing step can
be hot water (i.e., water having a temperature of at least about
35.degree. C., such as from about 35.degree. C. to about
100.degree. C.). In some cases, the degreasing agents can include
acidic or alkaline agents. For example, suitable acidic agents for
use in the degreasing step include phosphoric acid, sulfuric acid,
hydrochloric acid, or a mixture of these. In some cases, the
degreasing agent can include a wetting agent. Optionally, the
degreasing agent can be used in combination with electrochemical
cleaning. In certain cases, the level of degreasing is controlled
by the concentration of the agents, current density, degreasing
time, and/or temperature in the degreasing section. After
degreasing, the strip may be rinsed with water and dried prior to
lubrication.
[0056] Levelling
[0057] The process described herein can include at least one
levelling step applied to the aluminum alloy product. The term
"levelling," as used herein, includes processing the aluminum alloy
product to remove residual rolling stresses, thus generating an
aluminum alloy product that is tension-levelled. The levelling step
can also eliminate uneven areas resulting from the residual
stresses from the rolling processes. By eliminating uneven areas of
the aluminum alloy product, the cupping presses can run at
increased operating speeds and throughput, thus resulting in higher
productivity. The isotropic surface texture of the aluminum alloy
product reduces cracked domes and reduces tear-offs and
bleed-through and looper lines during the cupping and bodymaker
processes. Any suitable levelling process can be used, including
tension-levelling, stretch-levelling, roller-levelling, and/or
thermal-levelling. Not wishing to be bound by theory, mechanical
levelling such as tension-, stretch-, and roller-levelling
processes can extend certain ligaments in the strip, and
thermal-levelling processes can allow dislocations within the strip
to relax and deform to eliminate stress differences within the
strip, thereby ensuring lower residual stresses in the sheet and an
improved strip shape, i.e. flatness. In addition, the level of
distortion in the remaining portions of the sheet, e.g., after
blanking the cups on the cupping press, is greatly reduced.
[0058] In some examples, the strip may be heated to a peak metal
temperature of about 170.degree. C. to about 280.degree. C. (e.g.,
from about 200.degree. C. to about 240.degree. C.) for a period of
about 5 seconds to about 15 seconds to thermally-level the strip.
For example, the peak metal temperature for thermally-levelling the
strip can be about 170.degree. C., 171.degree. C., 172.degree. C.,
173.degree. C., 174.degree. C., 175.degree. C., 176.degree. C.,
177.degree. C., 178.degree. C., 179.degree. C., 180.degree. C.,
181.degree. C., 182.degree. C., 183.degree. C., 184.degree. C.,
185.degree. C., 186.degree. C., 187.degree. C., 188.degree. C.,
189.degree. C., 190.degree. C., 191.degree. C., 192.degree. C.,
193.degree. C., 194.degree. C., 195.degree. C., 196.degree. C.,
197.degree. C., 198.degree. C., 199.degree. C., 200.degree. C.,
201.degree. C., 202.degree. C., 203.degree. C., 204.degree. C.,
205.degree. C., 206.degree. C., 207.degree. C., 208.degree. C.,
209.degree. C., 210.degree. C., 211.degree. C., 212.degree. C.,
213.degree. C., 214.degree. C., 215.degree. C., 216.degree. C.,
217.degree. C., 218.degree. C., 219.degree. C., 220.degree. C.,
221.degree. C., 222.degree. C., 223.degree. C., 224.degree. C.,
225.degree. C., 226.degree. C., 227.degree. C., 228.degree. C.,
229.degree. C., 230.degree. C., 231.degree. C., 232.degree. C.,
233.degree. C., 234.degree. C., 235.degree. C., 236.degree. C.,
237.degree. C., 238.degree. C., 239.degree. C., 240.degree. C.,
241.degree. C., 242.degree. C., 243.degree. C., 244.degree. C.,
245.degree. C., 246.degree. C., 247.degree. C., 248.degree. C.,
249.degree. C., 250.degree. C., 251.degree. C., 252.degree. C.,
253.degree. C., 254.degree. C., 255.degree. C., 256.degree. C.,
257.degree. C., 258.degree. C., 259.degree. C., 260.degree. C.,
261.degree. C., 262.degree. C., 263.degree. C., 264.degree. C.,
265.degree. C., 266.degree. C., 267.degree. C., 268.degree. C.,
269.degree. C., 270.degree. C., 271.degree. C., 272.degree. C.,
273.degree. C., 274.degree. C., 275.degree. C., 276.degree. C.,
277.degree. C., 278.degree. C., 279.degree. C., or 280.degree. C.
The thermally-levelling process time can be, for example, about 5
seconds, 6 seconds, 7 seconds, 8 seconds, 9 seconds, 10 seconds, 11
seconds, 12 seconds, 13 seconds, 14 seconds, or 15 seconds. The
strip may be cooled to ambient temperature after the levelling
process. The line speed can be adjusted to impact the levelling
process. In some examples, the line speed may about 100 m/min to
about 300 m/min (e.g., from about 150 m/min to about 200 m/min).
For example, the line speed for levelling can be about 100 m/min,
105 m/min, 110 m/min, 115 m/min, 120 m/min, 125 m/min, 130 m/min,
135 m/min, 140 m/min, 145 m/min, 150 m/min, 155 m/min, 160 m/min,
165 m/min, 170 m/min, 175 m/min, 180 m/min, 185 m/min, 190 m/min,
195 m/min, 200 m/min, 205 m/min, 210 m/min, 215 m/min, 220 m/min,
225 m/min, 230 m/min, 235 m/min, 240 m/min, 245 m/min, 250 m/min,
255 m/min, 260 m/min, 265 m/min, 270 m/min, 275 m/min, 280 m/min,
285 m/min, 290 m/min, 295 m/min, or 300 m/min. In some examples,
the levelled product is substantially free of residual rolling
stresses. As used herein, the term "substantially free of residual
rolling stresses" means that the aluminum alloy products can have
an I-value of about 50 or less (e.g., about 45 or less, about 40 or
less, about 35 or less, about 30 or less, about 25 or less, about
20 or less, about 15 or less, about 10 or less, or about 5 or
less). The low level of residual rolling stresses facilitates press
feeding and remaining material (web) ejection processes.
[0059] Lubricating
[0060] The process described herein can optionally include at least
one lubricating step applied to the aluminum alloy product. The
term "lubricating," as used herein, includes processing the
aluminum alloy product to apply a lubricant for subsequent cupping
production. Optionally, the lubricant applied can be a dry film
lubricant. In some cases, the lubricant can be applied uniformly.
In some cases, a preferred level of lubrication is within the range
of 200 to 1000 mg/m.sup.2/side of the product (e.g., from about 200
mg/m.sup.2/side to about 1000 mg/m.sup.2/side or from about 500
mg/m.sup.2/side to about 800 mg/m.sup.2/side). In some cases, the
lubricating step eliminates the need for the use of additional
lubricant during downstream processing (e.g., during the cupping
process). In some cases, a post-lubricant may be applied to one or
both surfaces to help inhibit corrosion related to moisture in the
atmosphere and fretting corrosion due to interlap movement (e.g.,
caused by the overlapping layers of the aluminum alloy product as
coiled) during transportation and unwinding. The post-lubricant may
be applied to one or both surfaces in an amount of from about 5
mg/m.sup.2/side to about 100 mg/m.sup.2/side (e.g., from about 10
mg/m.sup.2/side to about 25 mg/m.sup.2/side or from about 20
mg/m.sup.2/side to about 50 mg/m.sup.2/side). In some cases, the
post-lubricant can include one or more of dibutyl adipate, dibutyl
sebacate, dihexyl adipate, dihexyl sebacate, dicyclohexyl adipate,
dicyclohexyl sebacate, dioctyl adipate, dioctyl sebacate,
diisodecyl adipate, diisodecyl sebacate, diundecyl adipate,
diundecyl sebacate, didodecanyl adipate, didodecanyl sebacate,
diphenyl sebacate, or diphenyl adipate.
Methods of Using and Downstream Processing
[0061] The aluminum alloy products and methods described herein can
be used for preparing beverage cans, food containers, or any other
desired application. In some examples, the aluminum alloy products
and methods can be used to prepare beverage can bodies. The
aluminum alloy products as described herein can be used in
downstream processing, such as in a cupping process. The aluminum
alloy products as described above can be moved in a cupping process
without using pinch rollers. In particular, rotating a magnet
adjacent to the aluminum product produces an induced current and
magnetic field, causing the aluminum product to move along the
generated magnetic field. The induced current and magnetic field
can be particularly useful in a rapid production line, such as in a
beverage can production line. In some cases, the magnet can be
placed in front of a cupping machine, and the magnet can be pulsed
to move the aluminum alloy product forward. This method of moving
the aluminum alloy product is referred to as the Lenz effect. By
utilizing the Lenz effect, the aluminum alloy product (e.g., sheet
or can preforms prepared from a sheet) can be advanced along the
production line without the use of pinch rollers that compress the
product and can potentially scratch the product surface or cause
surface deformations that are undesirable in a finished beverage
can.
EXAMPLES
Example 1
[0062] Sheets of 3104-01 aluminum were tested for yield strength,
ultimate tensile strength, spread, and total elongation. Sheets
were then partially annealed at peak metal temperatures of
180.degree. C., 200.degree. C. and 220.degree. C. for soaking times
of 5, 10, and 15 seconds. The sheets were tested for yield
strength, ultimate tensile strength, spread, and total elongation
after the soak time was complete. FIG. 1 shows the change in yield
strength according to soak time and soak temperature. FIG. 2 shows
the change in ultimate tensile strength according to soak time and
soak temperature. For both, the sheets treated at 220.degree. C.
reacted faster than those at lower temperatures. A decrease in
strength was observed in 5 seconds at 220.degree. C., whereas the
sheets treated at 180.degree. C., 200.degree. C. showed little
change in strength at 5 seconds. FIG. 3 shows the change in spread
according to soak time and soak temperature. Spread is the
numerical difference between the yield strength and the ultimate
tensile strength. Again, the sheets treated at 220.degree. C.
reacted faster than those at lower temperatures, but overall the
spread remained steady. FIG. 4 shows the change in elongation
according to soak time and soak temperature. Again, the sheets
treated at 220.degree. C. reacted faster than those at lower
temperatures, but did not show further reduction at 10 seconds or
15 seconds of soak time. The lower temperatures were slower to
react, but showed a decrease in elongation with increased soak
time.
Example 2
[0063] Sheets of 3104 were partially annealed at peak metal
temperatures of 180.degree. C., 200.degree. C. and 220.degree. C.
for soaking times of 5, 10, and 15 minutes. The sheets were then
cooled in a furnace from 170.degree. C. to 100.degree. C. followed
by an air quench and yield stress measured. Three replicates were
tested at each temperature for a total of 27 samples. A process
model was used to predict yield stress for 3104 sheets partially
annealed at peak metal temperatures ranging from 100.degree. C. to
240.degree. C. for soaking time of 1 second to 1,000,000 minutes.
FIG. 5 shows the experimental stress results represented with
markers overlaid on the lines of the process model. The yield
stress deceased over time, with greatest decrease seen at higher
temperatures. The modeled results correlate well the experimental
results at temperatures up to 200.degree. C. At temperatures beyond
200.degree. C., the experimental decrease in yield stress is
greater than that predicted by the model.
Illustrations of Suitable Alloys, Products, and Methods
[0064] As used below, any reference to a series of illustrative
alloys, products, or methods is to be understood as a reference to
each of those alloys, products, or methods disjunctively (e.g.,
"Illustrations 1-4" is to be understood as "Illustration 1, 2, 3,
or 4").
[0065] Illustration 1 is a method of producing an aluminum alloy
product, comprising casting an aluminum alloy comprising about
0.05-0.4 wt. % Cu, 0.25-0.9 wt. % Fe, 0.8-3.0 wt. % Mg, 0.1-2.0 wt.
% Mn, 0.2-0.7 wt. % Si, up to 0.1 wt. % Ti, up to 0.25 wt. % Zn, up
to 0.4 wt. % Cr, up to 0.15 wt. % impurities, and Al, to form a
cast aluminum alloy, heating the cast aluminum alloy, hot rolling
the cast aluminum alloy to produce a rolled product, cold rolling
the rolled product to produce an aluminum alloy product, and
levelling the aluminum alloy product.
[0066] Illustration 2 is the method of any preceding or subsequent
illustration, wherein casting is performed by semi-continuous
direct chill ingot casting or strip casting.
[0067] Illustration 3 is the method of any preceding or subsequent
illustration, wherein heating the cast aluminum alloy comprises
homogenizing the cast aluminum alloy
[0068] Illustration 4 is the method of any preceding or subsequent
illustration, further comprising degreasing the aluminum alloy
product.
[0069] Illustration 5 is the method of any preceding or subsequent
illustration, further comprising removing aluminum fines, rolling
oil, and debris from the aluminum alloy product.
[0070] Illustration 6 is the method of any preceding or subsequent
illustration, further comprising lubricating the aluminum alloy
product with a cupping lubricant.
[0071] Illustration 7 is an aluminum alloy product prepared
according to the method of any preceding or subsequent
illustration.
[0072] Illustration 8 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
comprises a 3xxx series aluminum alloy.
[0073] Illustration 9 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
comprises a 5xxx series aluminum alloy.
[0074] Illustration 10 is the aluminum alloy product of any
preceding or subsequent illustration, comprising about 0.05-0.3 wt.
% Cu, 0.4-0.8 wt. % Fe, 0.8-2.8 wt. % Mg, 0.1-1.5 wt. % Mn,
0.25-0.6 wt. % Si, up to 0.1 wt. % Ti, 0.1-0.25 wt. % Zn, up to
0.35 wt. % Cr, up to 0.15 wt. % impurities, and Al.
[0075] Illustration 11 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
product is a sheet.
[0076] Illustration 12 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
product comprises a thickness of less than about 240 .mu.m.
[0077] Illustration 13 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the thickness is from
about 170 .mu.m to less than about 240 .mu.m.
[0078] Illustration 14 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the thickness is from
about 180 .mu.m to about 230 .mu.m.
[0079] Illustration 15 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the sheet has a
longitudinal yield strength of at least about 260 MPa.
[0080] Illustration 16 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the longitudinal
yield strength is from about 260 MPa to about 300 MPa.
[0081] Illustration 17 is the aluminum alloy product of any
preceding or subsequent illustration, wherein one or more surfaces
of the aluminum alloy product comprise an isotropic surface
topography.
[0082] Illustration 18 is the aluminum alloy product of any
preceding or subsequent illustration, wherein one or more surfaces
of the aluminum alloy product has a texture aspect ratio of 0.1 to
0.7.
[0083] Illustration 19 is the aluminum alloy product of any
preceding or subsequent illustration, wherein one or more surfaces
of the aluminum alloy product comprise at least about 200 mg of
cupping lubricant per square meter per side (mg/m.sup.2/side).
[0084] Illustration 20 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the one or more
surfaces of the aluminum alloy product comprise cupping lubricant
in an amount of from about 200 mg/m.sup.2/side to about 1000
mg/m.sup.2/side.
[0085] Illustration 21 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the one or more
surfaces of the aluminum alloy product comprise a post-lubricant in
an amount of from about 5 mg/m.sup.2/side to about 100
mg/m.sup.2/side.
[0086] Illustration 22 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the post-lubricant
comprises dibutyl adipate, dibutyl sebacate, dihexyl adipate,
dihexyl sebacate, dicyclohexyl adipate, dicyclohexyl sebacate,
dioctyl adipate, dioctyl sebacate, diisodecyl adipate, diisodecyl
sebacate, diundecyl adipate, diundecyl sebacate, didodecanyl
adipate, didodecanyl sebacate, diphenyl sebacate or diphenyl
adipate.
[0087] Illustration 23 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the sheet is
tension-levelled in a longitudinal direction.
[0088] Illustration 24 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the sheet is
thermally-levelled at a temperature ranging from about 170.degree.
C. to about 280.degree. C.
[0089] Illustration 25 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
product is substantially free of aluminum fines and debris.
[0090] Illustration 26 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
product comprises a beverage can body.
[0091] Illustration 27 is an aluminum alloy product, comprising an
aluminum alloy comprising about 0.05-0.4 wt. % Cu, 0.25-0.9 wt. %
Fe, 0.8-3.0 wt. % Mg, 0.1-2.0 wt. % Mn, 0.2-0.7 wt. % Si, up to 0.1
wt. % Ti, up to 0.25 wt. % Zn, up to 0.4 wt. % Cr, up to 0.15 wt. %
impurities, and Al, wherein the aluminum alloy product comprises a
thickness of less than about 240 .mu.m.
[0092] Illustration 28 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the thickness is from
about 170 .mu.m to less than about 240 .mu.m.
[0093] Illustration 29 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the thickness is from
about 180 .mu.m to about 230 .mu.m.
[0094] Illustration 30 is the aluminum alloy product of any
preceding or subsequent illustration, wherein the aluminum alloy
comprises about 0.05-0.3 wt. % Cu, 0.4-0.8 wt. % Fe, 0.8-2.8 wt. %
Mg, 0.1-1.5 wt. % Mn, 0.25-0.6 wt. % Si, up to 0.1 wt. % Ti,
0.1-0.25 wt. % Zn, up to 0.35 wt. % Cr, up to 0.15 wt. %
impurities, and Al.
[0095] Illustration 31 is the aluminum alloy product of any
preceding or subsequent illustration, wherein one or more surfaces
of the aluminum alloy product has a texture aspect ratio of 0.1 to
0.7.
[0096] All patents, publications, and abstracts cited above are
incorporated herein by reference in their entireties. Various
embodiments of the invention have been described in fulfillment of
the various objectives of the invention. It should be recognized
that these embodiments are merely illustrative of the principles of
the present invention. Numerous modifications and adaptions thereof
will be readily apparent to those skilled in the art without
departing from the spirit and scope of the present invention as
defined in the following claims.
* * * * *