U.S. patent application number 16/697518 was filed with the patent office on 2020-03-26 for high-strength 6xxx aluminum alloys and methods of making the same.
This patent application is currently assigned to Novelis Inc.. The applicant listed for this patent is Novelis Inc.. Invention is credited to Hany Ahmed, Corrado Bassi, Cyrille Bezencon, Sazol Kumar Das, Aude Despois, Guillaume Florey, Rajeev G. Kamat, David Leyvraz, Juergen Timm, Wei Wen.
Application Number | 20200095664 16/697518 |
Document ID | / |
Family ID | 58191551 |
Filed Date | 2020-03-26 |
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United States Patent
Application |
20200095664 |
Kind Code |
A1 |
Wen; Wei ; et al. |
March 26, 2020 |
HIGH-STRENGTH 6XXX ALUMINUM ALLOYS AND METHODS OF MAKING THE
SAME
Abstract
Disclosed are high-strength aluminum alloys and methods of
making and processing such alloys. More particularly, disclosed is
a 6XXX series aluminum alloy exhibiting improved mechanical
strength, formability, corrosion resistance, and anodized
qualities. An exemplary method includes homogenizing, hot rolling,
solutionizing, and quenching. In some cases, the processing steps
can further include annealing and/or cold rolling.
Inventors: |
Wen; Wei; (Allison Park,
PA) ; Ahmed; Hany; (Atlanta, GA) ; Kamat;
Rajeev G.; (Marietta, GA) ; Bassi; Corrado;
(Salgesch, CH) ; Florey; Guillaume; (Veyras,
CH) ; Bezencon; Cyrille; (Chermignon, CH) ;
Timm; Juergen; (Steisslingen, DE) ; Leyvraz;
David; (Sierre, CH) ; Despois; Aude; (Grone,
CH) ; Das; Sazol Kumar; (Acworth, GA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novelis Inc. |
Atlanta |
GA |
US |
|
|
Assignee: |
Novelis Inc.
Atlanta
GA
|
Family ID: |
58191551 |
Appl. No.: |
16/697518 |
Filed: |
November 27, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15381707 |
Dec 16, 2016 |
10538834 |
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16697518 |
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62269385 |
Dec 18, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C22C 21/08 20130101;
C22C 21/14 20130101; C22C 21/16 20130101; C22C 21/06 20130101; C22F
1/05 20130101; C22C 21/02 20130101; C22F 1/043 20130101; C22C 21/18
20130101; C22F 1/057 20130101; C22F 1/047 20130101; B22D 7/005
20130101 |
International
Class: |
C22F 1/057 20060101
C22F001/057; B22D 7/00 20060101 B22D007/00; C22C 21/08 20060101
C22C021/08; C22C 21/02 20060101 C22C021/02; C22C 21/18 20060101
C22C021/18; C22C 21/16 20060101 C22C021/16; C22C 21/14 20060101
C22C021/14; C22F 1/047 20060101 C22F001/047; C22F 1/043 20060101
C22F001/043; C22F 1/05 20060101 C22F001/05; C22C 21/06 20060101
C22C021/06 |
Claims
1. A method of producing an aluminum alloy metal product, the
method comprising: casting an aluminum alloy to form an ingot,
wherein the aluminum alloy comprises about 0.6-0.9 wt. % Cu, about
0.8-1.3 wt. % Si, about 1.0-1.3 wt. % Mg, about 0.03-0.25 wt. % Cr,
about 0.05-0.2 wt. % Mn, about 0.15-0.3 wt. % Fe, up to about 0.2
wt. % Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt. % Sn, up
to about 0.9 wt. % Zn, up to about 0.1 wt. % Ti, up to about 0.07
wt. % Ni, up to about 0.15 wt. % of impurities, and Al;
homogenizing the ingot; hot rolling the ingot to produce a plate or
shate; and solutionizing the plate or shate at a temperature
between about 520.degree. C. and about 590.degree. C.
2. The method of claim 1, wherein the homogenizing step comprises
heating the ingot to a temperature of about 520.degree. C. to about
580.degree. C.
3. The method of claim 1, wherein the hot rolling step is conducted
at an entry temperature of about 500.degree. C. to about
540.degree. C. and an exit temperature of about 250.degree. C. to
about 380.degree. C.
4. The method of claim 1, further comprising annealing the plate or
shate.
5. The method of claim 4, wherein the annealing step is performed
at a temperature that is between about 400.degree. C. and about
500.degree. C. for a soaking time of about 30 to about 120
minutes.
6. The method of claim 1, further comprising cold rolling the plate
or shate.
7. The method of claim 1, further comprising quenching the plate or
shate after the solutionizing step.
8. The method of claim 1, further comprising aging the plate or
shate.
9. The method of claim 8, wherein the aging comprises heating the
plate or shate between about 180.degree. C. to about 225.degree.
C.
10. A method of producing an aluminum alloy product, the method
comprising: casting an aluminum alloy to form an ingot, wherein the
aluminum alloy comprises about 0.5-2.0 wt. % Cu, about 0.5-1.5 wt.
% Si, about 0.5-1.5 wt. % Mg, about 0.001-0.25 wt. % Cr, about
0.005-0.4 wt. % Mn, about 0.1-0.3 wt. % Fe, up to about 0.2 wt. %
Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt. % Sn, up to
about 4.0 wt. % Zn, up to about 0.15 wt. % Ti, up to about 0.1 wt.
% Ni, up to about 0.15 wt. % of impurities, and Al; homogenizing
the ingot; hot rolling and cold rolling the ingot to produce a
rolled aluminum alloy product; and solutionizing the rolled
aluminum alloy product, wherein a solutionizing temperature is
between about 540.degree. C. and about 590.degree. C.
11. The method of claim 10, wherein the aluminum alloy product
comprises about 0.5-1.8 wt. % Cu, about 0.5-1.0 wt. % Si, about
0.6-1.2 wt. % Mg, about 0.05-0.2 wt. % Cr, about 0.05-0.25 wt. %
Mn, about 0.1-0.3 wt. % Fe, up to about 0.15 wt. % Zr, up to about
0.15 wt. % Sc, up to about 0.15 wt. % Sn, up to about 0.4 wt. % Zn,
up to about 0.15 wt. % Ti, less than 0.05 wt. % Ni, up to about
0.15 wt. % of impurities, and Al.
12. The method of claim 10, wherein the aluminum alloy product
comprises about 0.6-1.7 wt. % Cu, about 0.5-0.9 wt. % Si, about
0.7-1.1 wt. % Mg, about 0.05-0.15 wt. % Cr, about 0.1-0.2 wt. % Mn,
about 0.1-0.3 wt. % Fe, up to about 0.1 wt. % Zr, up to about 0.1
wt. % Sc, up to about 0.1 wt. % Sn, up to about 0.25 wt. % Zn, up
to about 0.15 wt. % Ti, less than 0.05 wt. % Ni, up to about 0.15
wt. % of impurities, and Al.
13. The method of claim 10, wherein the aluminum alloy product has
a Si to Mg ratio of from about 0.55:1 to about 1.30:1 by
weight.
14. The method of claim 10, wherein the aluminum alloy product has
an excess Si content of from -0.5 to 0.1.
15. The method of claim 10, wherein the homogenizing step is a
one-step homogenization comprising heating the ingot to a
temperature of about 520.degree. C. to about 580.degree. C.
16. The method of claim 10, wherein the homogenizing step is a
two-step homogenization comprising heating the ingot to a
temperature of about 480.degree. C. to about 520.degree. C., and
further heating the ingot to a temperature of about 520.degree. C.
to about 580.degree. C.
17. The method of claim 10, wherein the hot rolling is conducted at
an entry temperature of about 500.degree. C. to about 540.degree.
C.
18. The method of claim 10, further comprising quenching the
aluminum alloy product after the solutionizing step.
19. The method of claim 10, wherein the aluminum alloy product is a
plate, shate, or sheet.
20. A method of producing an aluminum alloy product, the method
comprising: casting an aluminum alloy to form an ingot, wherein the
aluminum alloy comprises about 0.9-1.5 wt. % Cu, about 0.7-1.1 wt.
% Si, about 0.7-1.2 wt. % Mg, about 0.06-0.15 wt. % Cr, about
0.05-0.3 wt. % Mn, about 0.1-0.3 wt. % Fe, up to about 0.2 wt. %
Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt. % Sn, up to
about 0.2 wt. % Zn, up to about 0.15 wt. % Ti, up to about 0.07 wt.
% Ni, up to about 0.15 wt. % of impurities, and Al; homogenizing
the ingot; hot rolling the ingot to produce a plate, shate or
sheet; and solutionizing the plate, shate or sheet at a temperature
between about 520.degree. C. and about 590.degree. C.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a divisional of U.S. patent
application Ser. No. 15/381,707 filed Dec. 16, 2016, which claims
the benefit of U.S. Provisional Patent Application No. 62/269,385
filed Dec. 18, 2015, which are hereby incorporated by reference in
their entireties.
FIELD OF THE INVENTION
[0002] The invention is directed to high-strength aluminum alloys
and methods of making and processing the same. The invention
further relates to 6XXX aluminum alloys exhibiting improved
mechanical strength, formability, corrosion resistance, and
anodized qualities.
BACKGROUND
[0003] Recyclable aluminum alloys with high strength are desirable
for improved product performance in many applications, including
transportation (encompassing without limitation, e.g., trucks,
trailers, trains, and marine) applications, electronic
applications, and automobile applications. For example, a
high-strength aluminum alloy in trucks or trailers would be lighter
than conventional steel alloys, providing significant emission
reductions that are needed to meet new, stricter government
regulations on emissions. Such alloys should exhibit high strength,
high formability, and corrosion resistance.
[0004] However, identifying processing conditions and alloy
compositions that will provide such an alloy has proven to be a
challenge. In addition, the hot rolling of compositions with the
potential of exhibiting the desired properties often results in
edge cracking issues and the propensity for hot tearing.
SUMMARY
[0005] 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.
[0006] Provided herein are methods of preparing 6XXX series
aluminum alloys, the aluminum alloys, and products comprising the
alloys.
[0007] One aspect relates to methods of processing aluminum. For
example, disclosed is a method of producing an aluminum alloy metal
product, the method comprising casting an aluminum alloy to form an
ingot, wherein the aluminum alloy comprises about 0.9-1.5 wt. % Cu,
about 0.7-1.1 wt. % Si, about 0.7-1.2 wt. % Mg, about 0.06-0.15 wt.
% Cr, about 0.05-0.3 wt. % Mn, about 0.1-0.3 wt. % Fe, up to about
0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt. % Sn,
up to about 0.2 wt. % Zn, up to about 0.15 wt. % Ti, up to about
0.07 wt. % Ni, and up to about 0.15 wt. % of impurities, with the
remainder as Al; homogenizing the ingot; hot rolling the ingot to
produce a plate, shate, or sheet; and solutionizing the plate,
shate or sheet at a temperature between about 520.degree. C. and
about 590.degree. C. Throughout this application, all elements are
described in weight percentage (wt. %) based on the total weight of
the alloy. In some examples, the homogenizing step can include
heating the ingot to a temperature of about 520.degree. C. to about
580.degree. C. In some cases, the hot rolling step can be conducted
at an entry temperature of about 500.degree. C. to about
540.degree. C. and an exit temperature of about 250.degree. C. to
about 380.degree. C. Optionally, the methods can include annealing
the plate, shate or sheet. In some such cases, the annealing step
can be performed at a temperature that is between about 400.degree.
C. and about 500.degree. C. for a soaking time of about 30 to about
120 minutes. In yet other aspects, the methods can include cold
rolling the plate, shate or sheet. In some cases, the methods can
include quenching the plate, shate or sheet after the solutionizing
step. In some other aspects, the methods include aging the plate,
shate or sheet. In some such cases, the aging step includes heating
the plate, shate or sheet between about 180.degree. C. to about
225.degree. C. for a period of time.
[0008] Another aspect relates to methods of processing aluminum
that include manufacturing by casting an aluminum alloy to form an
ingot, wherein the aluminum alloy comprises about 0.6-0.9 wt. % Cu,
about 0.8-1.3 wt. % Si, about 1.0-1.3 wt. % Mg, about 0.03-0.25 wt.
% Cr, about 0.05-0.2 wt. % Mn, about 0.15-0.3 wt. % Fe, up to about
0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt. % Sn,
up to about 0.9 wt. % Zn, up to about 0.1 wt. % Ti, up to about
0.07 wt. % Ni, and up to about 0.15 wt. % of impurities, with the
remainder as Al; homogenizing the ingot; hot rolling and cold
rolling the ingot to produce a rolled product; and solutionizing
the rolled product, wherein the solutionizing temperature is
between about 520.degree. C. and about 590.degree. C. In some
examples, the homogenizing step is a one-step homogenization that
can include heating the ingot to a temperature of about 520.degree.
C. to about 580.degree. C. for a period of time. In other examples,
the homogenizing step is a two-step homogenization that can include
heating the ingot to a temperature of about 480.degree. C. to about
520.degree. C. for a period of time and further heating the ingot
to a temperature of about 520.degree. C. to about 580.degree. C.
for a period of time. In some cases, the hot rolling step can be
conducted at an entry temperature of about 500.degree. C. to about
540.degree. C. and an exit temperature of about 250.degree. C. to
about 380.degree. C. In some cases, the methods can include
quenching the rolled product after the solutionizing step. In some
other aspects, the methods include aging the rolled product. In
some such cases, the aging step includes heating the plate, shate
or sheet between about 180.degree. C. to about 225.degree. C. for a
period of time.
[0009] Another aspect relates to methods of processing aluminum
that include manufacturing by casting an aluminum alloy to form an
ingot, wherein the aluminum alloy comprises about 0.5-2.0 wt. % Cu,
about 0.5-1.5 wt. % Si, about 0.5-1.5 wt. % Mg, about 0.001-0.25
wt. % Cr, about 0.005-0.4 wt. % Mn, about 0.1-0.3 wt. % Fe, up to
about 0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about 0.25 wt.
% Sn, up to about 4.0 wt. % Zn, up to about 0.15 wt. % Ti, up to
about 0.1 wt. % Ni, and up to about 0.15 wt. % of impurities, with
the remainder as Al; homogenizing the ingot; hot rolling and cold
rolling the ingot to produce a rolled product; and solutionizing
the rolled product, wherein the solutionizing temperature is
between about 520.degree. C. and about 590.degree. C. In some
examples, the homogenizing step is a one-step homogenization that
can include heating the ingot to a temperature of about 520.degree.
C. to about 580.degree. C. for a period of time. In other examples,
the homogenizing step is a two-step homogenization that can include
heating the ingot to a temperature of about 480.degree. C. to about
520.degree. C. for a period of time and further heating the ingot
to a temperature of about 520.degree. C. to about 580.degree. C.
for a period of time. In some cases, the hot rolling step can be
conducted at an entry temperature of about 500.degree. C. to about
540.degree. C. and an exit temperature of about 250.degree. C. to
about 380.degree. C. In some cases, the methods can include
quenching the rolled product after the solutionizing step. In some
other aspects, the methods include aging the rolled product. In
some such cases, the aging step includes heating the sheet between
about 180.degree. C. to about 225.degree. C. for a period of
time.
[0010] Also disclosed is an aluminum alloy comprising about 0.9-1.5
wt. % Cu, about 0.7-1.1 wt. % Si, about 0.7-1.2 wt. % Mg, about
0.06-0.15 wt. % Cr, about 0.05-0.3 wt. % Mn, about 0.1-0.3 wt. %
Fe, up to about 0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about
0.25 wt. % Sn, up to about 0.2 wt. % Zn, up to about 0.15 wt. % Ti,
up to about 0.07 wt. % Ni, and up to about 0.15 wt. % of
impurities, with the remainder as Al.
[0011] Also disclosed is an aluminum alloy comprising about 0.6-0.9
wt. % Cu, about 0.8-1.3 wt. % Si, about 1.0-1.3 wt. % Mg, about
0.03-0.25 wt. % Cr, about 0.05-0.2 wt. % Mn, about 0.15-0.3 wt. %
Fe, up to about 0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about
0.25 wt. % Sn, up to about 0.9 wt. % Zn, up to about 0.1 wt. % Ti,
up to about 0.07 wt. % Ni, and up to about 0.15 wt. % of
impurities, with the remainder as Al. Optionally, the aluminum
alloy has a Si to Mg ratio of from about 0.55:1 to about 1.30:1 by
weight. Optionally, the aluminum alloy has an excess Si content of
from -0.5 to 0.1, as described in more detail below.
[0012] Also disclosed is an aluminum alloy comprising about 0.5-2.0
wt. % Cu, about 0.5-1.5 wt. % Si, about 0.5-1.5 wt. % Mg, about
0.001-0.25 wt. % Cr, about 0.005-0.4 wt. % Mn, about 0.1-0.3 wt. %
Fe, up to about 0.2 wt. % Zr, up to about 0.2 wt. % Sc, up to about
0.25 wt. % Sn, up to about 0.3 wt. % Zn, up to about 0.1 wt. % Ti,
up to about 0.1 wt. % Ni, and up to about 0.15 wt. % of impurities,
with the remainder as Al.
[0013] Further disclosed are products (e.g., transportation body
parts, automotive body parts, or electronic device housings)
comprising an alloy obtained according to the methods provided
herein.
[0014] Further aspects, objects, and advantages of the invention
will become apparent upon consideration of the detailed description
and figures that follow.
BRIEF DESCRIPTION OF THE FIGURES
[0015] FIG. 1 is a chart that shows a comparison between the
tensile properties of alloy compositions TB1, TB2, TB3, and TB4
after processing to T4 temper.
[0016] FIG. 2 is a chart that shows a comparison between the
bendability of alloy compositions TB1, TB2, TB3, and TB4 after
processing to T4 temper.
[0017] FIG. 3 is a chart that shows a comparison between the
tensile properties of alloy compositions TB1, TB2, TB3, and TB4
after processing to T6 temper.
[0018] FIG. 4 shows orientation distribution function (ODF) graphs
of the TB1 alloy plotted in sections at .phi.2=0.degree.,
45.degree., and 65.degree., respectively. Sample (a) is a regular
T4 condition control obtained by solutionizing F temper directly,
while sample (b) is a modified T4 condition alloy prepared by
annealing the F temper alloy and then solutionizing the as-annealed
O temper.
[0019] FIG. 5 is a chart that shows a comparison between the
tensile properties of the industrial alloy TB1 after processing to
T6 temper with annealing (right bar chart) and without annealing
(left bar chart).
[0020] FIG. 6 is a chart that shows the uniform elongation (at T4
condition) and yield strength (at T6 condition) of the alloy
compositions P7, P8, and P14 at a temperature ranging from
550.degree. C. 560.degree. C. (indicated as SHT temperature 1).
[0021] FIG. 7 is a chart that shows the yield strength (at T6
condition) of the alloy compositions P7, P8, and P14 at a
temperature ranging from 560.degree. C. 570.degree. C. (indicated
as SHT temperature 2).
[0022] FIG. 8 is a chart that shows the yield strength (at T6
condition) of the alloy compositions P7, P8, and P14 at a
temperature ranging from 570.degree. C. 580.degree. C. (indicated
as SHT temperature 3).
[0023] FIG. 9 is a chart that shows the yield strength (Rp02) of
the alloy compositions SL1 (left histogram bar in each set), SL2
(second from left histogram bar in each set), SL3 (third from left
histogram bar in each set), and SL4 (right histogram bar in each
set). The figure shows comparative results from samples that were
prepared with low and high peak metal temperatures (PMTs) for the
solution heat treatment step (SHT).
[0024] FIG. 10 is a chart that shows the ultimate tensile strength
(Rm) of the alloy compositions SL1 (left histogram bar in each
set), SL2 (second from left histogram bar in each set), SL3 (third
from left histogram bar in each set), and SL4 (right histogram bar
in each set). The figure shows comparative results from samples
that were prepared with low and high PMTs for the solution heat
treatment step.
[0025] FIG. 11 is a chart that shows the amount of uniform
elongation (Ag) of the alloy compositions SL1 (left histogram bar
in each set), SL2 (second from left histogram bar in each set), SL3
(third from left histogram bar in each set), and SL4 (right
histogram bar in each set). The figure shows comparative results
from samples that were prepared with low and high PMTs for the
solution heat treatment step.
[0026] FIG. 12 is a chart that shows a tensile curve for alloy SL3,
showing the amount of total elongation (A80) of the alloy
composition.
[0027] FIG. 13 is a chart that shows bending results for the amount
of uniform elongation (Ag) of the alloy compositions SL1 (left
histogram bar in each set), SL2 (second from left histogram bar in
each set), SL3 (third from left histogram bar in each set), and SL4
(right histogram bar in each set). The figure shows comparative
results from samples that were prepared with low and high PMT
homogenization. The figure shows comparative results from samples
that were prepared with low and high PMT homogenization.
[0028] FIG. 14 is a chart that shows the yield strength results
(Rp02) to bending results for the alloy compositions SL1, SL2, SL3,
and SL4.
[0029] FIG. 15 is a chart that shows crush test results of Alloy
SL3 in T6 temper, showing the applied energy and applied load as a
function of displacement.
[0030] FIG. 16A is a digital image of Alloy SL3 sample 2 after the
crush test.
[0031] FIG. 16B is a line drawing derived from the digital image of
FIG. 16A of Alloy SL3 sample 2 after the crush test.
[0032] FIG. 16C is a digital image of Alloy SL3 sample 2 after the
crush test.
[0033] FIG. 16D is a line drawing derived from the digital image of
FIG. 16C of Alloy SL3 sample 2 after the crush test.
[0034] FIG. 16E is a digital image of Alloy SL3 sample 2 after the
crush test.
[0035] FIG. 16F is a line drawing derived from the digital image of
FIG. 16E of Alloy SL3 sample 2 after the crush test.
[0036] FIG. 17A is a digital image of Alloy SL3 sample 3 after the
crush test.
[0037] FIG. 17B is a line drawing derived from the digital image of
FIG. 17A of Alloy SL3 sample 3 after the crush test.
[0038] FIG. 17C is a digital image of Alloy SL3 sample 3 after the
crush test.
[0039] FIG. 17D is a line drawing derived from the digital image of
FIG. 17C of Alloy SL3 sample 3 after the crush test.
[0040] FIG. 17E is a digital image of Alloy SL3 sample 3 after the
crush test.
[0041] FIG. 17F is a line drawing derived from the digital image of
FIG. 17E of Alloy SL3 sample 3 after the crush test.
[0042] FIG. 18 is a chart that shows the crash test results of
Alloy SL3 in T6 temper, showing applied energy and applied load as
a function of displacement.
[0043] FIG. 19A is a digital image of Alloy SL3 sample 2 after the
crash test.
[0044] FIG. 19B is a line drawing derived from the digital image of
FIG. 19A of Alloy SL3 sample 2 after the crash test.
[0045] FIG. 19C is a digital image of Alloy SL3 sample 2 after the
crash test.
[0046] FIG. 19D is a line drawing derived from the digital image of
FIG. 19C of Alloy SL3 sample 2 after the crash test.
[0047] FIG. 20A is a digital image of Alloy SL3 sample 3 after the
crash test.
[0048] FIG. 20B is a line drawing derived from the digital image of
FIG. 20A of Alloy SL3 sample 3 after the crash test.
[0049] FIG. 20C is a digital image of Alloy SL3 sample 3 after the
crash test.
[0050] FIG. 20D is a line drawing derived from the digital image of
FIG. 20C of Alloy SL3 sample 3 after the crash test.
[0051] FIG. 21 is a chart that shows the effects of different
quenches on the yield strength (Rp02) and bendability of Alloy
SL2.
[0052] FIG. 22 is a chart that shows the yield strength results
(Rp02) of the alloys S164, S165, S166, S167, S168 and S169 after
different heat treatments. The left histogram bar in each set
represents the heat treatment indicated in the figure legend as
T8x. The second from left histogram bar in each set represents the
heat treatment indicated in the figure legend as T62-2. The third
from left histogram bar in each set represents the heat treatment
indicated in the figure legend as T82. The right histogram bar in
each set represents the heat treatment indicated in the figure
legend as T6.
[0053] FIG. 23 is a chart that shows the hardness measurements of
the alloys S164, S165, S166, S167, S168 and S169 after different
solutionizing conditions.
[0054] FIG. 24 is a chart that shows tensile strengths of exemplary
alloys described herein. The alloys comprise various amounts of Zn
in the composition.
[0055] FIG. 25 is a chart that shows formability of exemplary
alloys described herein. The alloys comprise various amounts of Zn
in the composition.
[0056] FIG. 26 is a chart that shows the tensile strengths of
exemplary alloys described herein to the formability of exemplary
alloys described herein. The alloys comprise various amounts of Zn
in the composition.
[0057] FIG. 27 is a chart that shows the increase in tensile
strengths of exemplary alloys described herein. The alloys comprise
various amounts of Zn in the composition. The alloys were subjected
to various aging methods resulting in various temper
conditions.
[0058] FIG. 28 is a chart that shows elongation of exemplary alloys
described herein. The alloys comprise various amounts of Zn in the
composition.
[0059] FIG. 29 is a chart that shows the tensile strengths of
exemplary alloys described herein. The alloys comprise various
amounts of Zr in the composition. The alloys were rolled to 2 mm
and 10 mm gauge. The alloys were subjected to aging methods
resulting in T6 temper condition.
[0060] FIG. 30 is a chart that shows formability of exemplary
alloys described herein. The alloys comprise various amounts of Zr
in the composition. The alloys were rolled to 2 mm gauge. The
alloys were subjected to aging methods resulting in T4 temper
condition.
[0061] FIG. 31 is a chart that shows formability of exemplary
alloys described herein. The alloys comprise various amounts of Zr
in the composition. The alloys were rolled to 2 mm gauge. The
alloys were subjected to aging methods resulting in T6 temper
condition.
[0062] FIG. 32 is a chart that shows maximum corrosion depth of
exemplary alloys described herein. The alloys comprise various
amounts of Zr in the composition. The alloys were rolled to 2 mm
gauge.
[0063] FIG. 33 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0064] FIG. 34 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0065] FIG. 35 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0066] FIG. 36 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0067] FIG. 37 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0068] FIG. 38 is a digital image of a cross-sectional view of
exemplary alloys described herein after corrosion testing. The
alloys comprise various amounts of Zr in the composition. The
alloys were rolled to 2 mm gauge.
[0069] FIG. 39 is an illustration depicting the outer bend angle
(a).
DETAILED DESCRIPTION OF THE INVENTION
Definitions and Descriptions
[0070] 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.
[0071] In this description, reference is made to alloys identified
by aluminum industry designations, such as "series" or "6XXX." 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.
[0072] As used herein, the meaning of "a," "an," or "the" includes
singular and plural references unless the context clearly dictates
otherwise.
[0073] 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 15 mm, greater than 20
mm, greater than 25 mm, greater than 30 mm, greater than 35 mm,
greater than 40 mm, greater than 45 mm, greater than 50 mm, or
greater than 100 mm.
[0074] 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 4 mm, 5 mm, 6 mm, 7 mm, 8
mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, or 15 mm.
[0075] 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 4 mm, less than 3 mm, less
than 2 mm, less than 1 mm, less than 0.5 mm, less than 0.3 mm, or
less than 0.1 mm.
[0076] Reference is made in this application to alloy temper or
condition. For an understanding of the alloy temper descriptions
most commonly used, see "American National Standards (ANSI) H35 on
Alloy and Temper Designation Systems." An F condition or temper
refers to an aluminum alloy as fabricated. An O condition or temper
refers to an aluminum alloy after annealing. A T4 condition or
temper refers to an aluminum alloy after solution heat treatment
(SHT) (i.e., solutionization) followed by natural aging. A T6
condition or temper refers to an aluminum alloy after solution heat
treatment followed by artificial aging (AA).
[0077] 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.
Alloy Compositions
[0078] Described below are novel 6XXX series aluminum alloys. In
certain aspects, the alloys exhibit high strength, high
formability, and corrosion resistance. The properties of the alloys
are achieved due to the methods of processing the alloys to produce
the described plates, shates, and sheets. The alloys can have the
following elemental composition as provided in Table 1:
TABLE-US-00001 TABLE 1 Element Weight Percentage (wt. %) Cu 0.9-1.5
Si 0.7-1.1 Mg 0.7-1.2 Cr 0.06-0.15 Mn 0.05-0.3 Fe 0.1-0.3 Zr 0-0.2
Sc 0-0.2 Sn 0-0.25 Zn 0-0.2 Ti 0-0.15 Ni 0-0.07 Others 0-0.05
(each) 0-0.15 (total) Al Remainder
[0079] In other examples, the alloys can have the following
elemental composition as provided in Table 2.
TABLE-US-00002 TABLE 2 Element Weight Percentage (wt. %) Cu 0.6-0.9
Si 0.8-1.3 Mg 1.0-1.3 Cr 0.03-0.25 Mn 0.05-0.2 Fe 0.15-0.3 Zr 0-0.2
Sc 0-0.2 Sn 0-0.25 Zn 0-0.9 Ti 0-0.1 Ni 0-0.07 Others 0-0.05 (each)
0-0.15 (total) Al Remainder
[0080] In other examples, the alloys can have the following
elemental composition as provided in Table 3.
TABLE-US-00003 TABLE 3 Element Weight Percentage (wt. %) Cu 0.5-2.0
Si 0.5-1.5 Mg 0.5-1.5 Cr 0.001-0.25 Mn 0.005-0.4 Fe 0.1-0.3 Zr
0-0.2 Sc 0-0.2 Sn 0-0.25 Zn 0-4.0 Ti 0-0.15 Ni 0-0.1 Others 0-0.05
(each) 0-0.15 (total) Al Remainder
Aluminum Alloys for Preparing Plates and Shates
[0081] In one example, an aluminum alloy can have the following
elemental composition as provided in Table 4. In certain aspects,
the alloy is used to prepare aluminum plates and shates.
TABLE-US-00004 TABLE 4 Element Weight Percentage (wt. %) Cu 0.6-0.9
Si 0.8-1.3 Mg 1.0-1.3 Cr 0.03-0.15 Mn 0.05-0.2 Fe 0.15-0.3 Zr 0-0.2
Sc 0-0.2 Sn 0-0.25 Zn 0-0.9 Ti 0-0.1 Ni 0-0.07 Others 0-0.05 (each)
0-0.15 (total) Al Remainder
[0082] In another example, an aluminum alloy for use in preparing
aluminum plates and shates can have the following elemental
composition as provided in Table 5.
TABLE-US-00005 TABLE 5 Element Weight Percentage (wt. %) Cu
0.65-0.9 Si 0.9-1.15 Mg 1.05-1.3 Cr 0.03-0.15 Mn 0.05-0.18 Fe
0.18-0.25 Zr 0.01-0.2 Sc 0-0.2 Sn 0-0.2 Zn 0.001-0.9 Ti 0-0.1 Ni
0-0.05 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0083] In another example, an aluminum alloy for use in preparing
aluminum plates and shates can have the following elemental
composition as provided in Table 6.
TABLE-US-00006 TABLE 6 Element Weight Percentage (wt. %) Cu
0.65-0.9 Si 1.0-1.1 Mg 1.1-1.25 Cr 0.05-0.12 Mn 0.08-0.15 Fe
0.15-0.2 Zr 0.01-0.15 Sc 0-0.15 Sn 0-0.2 Zn 0.004-0.9 Ti 0-0.03 Ni
0-0.05 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0084] In certain examples, the disclosed alloy includes copper
(Cu) in an amount from about 0.6% to about 0.9% (e.g., from 0.65%
to 0.9%, from 0.7% to 0.9%, or from 0.6% to 0.7%) based on the
total weight of the alloy. For example, the alloy can include 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% Cu. All expressed in wt. %.
[0085] In certain examples, the disclosed alloy includes silicon
(Si) in an amount from about 0.8% to about 1.3% (e.g., from 0.8% to
1.2%, from 0.9% to 1.2%, from 0.8% to 1.1%, from 0.9% to 1.15%,
from 1.0% to 1.1%, or from 1.05 to 1.2%) 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%, 1.01%, 1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%,
1.09%, 1.1%, 1.11%, 1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%,
1.18%, 1.19%, or 1.2%, 1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%,
1.27%, 1.28%, 1.29%, or 1.3% Si. All expressed in wt. %.
[0086] In certain examples, the disclosed alloy includes magnesium
(Mg) in an amount from about 1.0% to about 1.3% (e.g., from 1.0% to
1.25%, from 1.1% to 1.25%, from 1.1% to 1.2%, from 1.0% to 1.2%,
from 1.05% to 1.3%, or from 1.15% to 1.3%) based on the total
weight of the alloy. For example, the alloy can include 1.0%,
1.01%, 1.02%, 1.03%, 1.04%, 1.05%1.06%1.07%1.08%1.09%, 1.1%, 1.11%,
1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19%, 1.2%,
1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%, 1.29%, or
1.3% Mg. All expressed in wt. %.
[0087] In certain aspects, Cu, Si and Mg can form precipitates in
the alloy to result in an alloy with higher strength. These
precipitates can form during the aging processes, after solution
heat treatment. During the precipitation process, metastable
Guinier Preston (GP) zones can form, which in turn transfer to
.beta.'' needle shape precipitates that contribute to precipitation
strengthening of the disclosed alloys. In certain aspects, addition
of Cu leads to the formation of lathe-shaped L phase precipitation,
which is a precursor of Q' precipitate phase formation and which
further contributes to strength. In certain aspects, the Cu and
Si/Mg ratios are controlled to avoid detrimental effects to
corrosion resistance.
[0088] In certain aspects, for a combined effect of strengthening,
formability and corrosion resistance, the alloy has a Cu content of
less than about 0.9 wt. % along with a controlled Si to Mg ratio
and a controlled excess Si range, as further described below.
[0089] The Si to Mg ratio may be from about 0.55:1 to about 1.30:1
by weight. For example, the Si to Mg ratio may be from about 0.6:1
to about 1.25:1 by weight, from about 0.65:1 to about 1.2:1 by
weight, from about 0.7:1 to about 1.15:1 by weight, from about
0.75:1 to about 1.1:1 by weight, from about 0.8:1 to about 1.05:1
by weight, from about 0.85:1 to about 1.0:1 by weight, or from
about 0.9:1 to about 0.95:1 by weight. In certain aspects, the Si
to Mg ratio is from 0.8:1 to 1.15:1. In certain aspects, the Si to
Mg ratio is from 0.85:1 to 1:1.
[0090] In certain aspects, the alloy may use an almost balanced Si
to slightly under-balanced Si approach in alloy design instead of a
high excess Si approach. In certain aspects, excess Si is about
-0.5 to 0.1. Excess Si as used herein is defined by the
equation:
Excess Si=(alloy wt. % Si)-[(alloy wt. % Mg)-1/6.times.(alloy wt. %
Fe+Mn+Cr)].
For example, excess Si can be -0.50, -0.49, -0.48, -0.47, -0.46,
-0.45, -0.44, -0.43, -0.42, -0.41, -0.40, -0.39, -0.38, -0.37,
-0.36, -0.35, -0.34, -0.33, -0.32, -0.31, -0.30, -0.29, -0.28,
-0.27, -0.26, -0.25, -0.24, -0.23, -0.22, -0.21, -0.20, -0.19,
-0.18, -0.17, -0.16, -0.15, -0.14, -0.13, -0.12, -0.11, -0.10,
-0.09, -0.08, -0.07, -0.06, -0.05, -0.04, -0.03, -0.02, -0.01, 0,
0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, or 0.10. In
certain aspects, the alloy has Cu<0.9 wt. %, the Si/Mg ratio is
0.85-0.1, and excess Si is -0.5-0.1.
[0091] In certain aspects, the alloy includes chromium (Cr) in an
amount from about 0.03% to about 0.25% (e.g., from 0.03% to 0.15%,
from 0.05% to 0.13%, from 0.075% to 0.12%, from 0.03% to 0.04%,
from 0.08% to 0.15%, from 0.03% to 0.045%, from 0.04% to 0.06%,
from 0.035% to 0.045%, from 0.04% to 0.08%, from 0.06% to 0.13%,
from 0.06% to 0.22%, from 0.1% to 0.13%, or from 0.11% to 0.23%)
based on the total weight of the alloy. For example, the alloy can
include 0.03%, 0.035%, 0.04%, 0.045%, 0.05%, 0.055%, 0.06%, 0.065%,
0.07%, 0.075%, 0.08%, 0.085%, 0.09%, 0.095%, 0.1%, 0.105%, 0.11%,
0.115%, 0.12%, 0.125%, 0.13%, 0.135%, 0.14%, 0.145%, 0.15%, 0.155%,
0.16%, 0.165%, 0.17%, 0.175%, 0.18% 0.185%, 0.19%, 0.195%, 0.20%,
0.205%, 0.21%, 0.215%, 0.22%, 0.225%, 0.23%, 0.235%, 0.24%, 0.245%,
or 0.25% Cr. All expressed in wt. %.
[0092] In certain examples, the alloy can include manganese (Mn) in
an amount from about 0.05% to about 0.2% (e.g., from 0.05% to 0.18%
or from 0.1% to 0.18%) based on the total weight of the alloy. For
example, the alloy can include 0.05%, 0.051%, 0.052%, 0.053%,
0.054%, 0.055%, 0.056%, 0.057%, 0.058%, 0.059%, 0.06%, 0.061%,
0.062%, 0.063%, 0.064%, 0.065%, 0.066%, 0.067%, 0.068%, 0.069%,
0.07%, 0.071%, 0.072%, 0.073%, 0.074%, 0.075%, 0.076%, 0.077%,
0.078%, 0.079%, 0.08%, 0.081%, 0.082%, 0.083%, 0.084%, 0.085%,
0.086%, 0.087%, 0.088%, 0.089%, 0.09%, 0.091%, 0.092%, 0.093%,
0.094%, 0.095%, 0.096%, 0.097%, 0.098%, 0.099%, 0.1%, 0.11%, 0.12%,
0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, or 0.2% Mn. All
expressed in wt. %. In certain aspects, the Mn content was used to
minimize coarsening of constituent particles.
[0093] In certain aspects, some Cr is used to replace Mn in forming
dispersoids. Replacing Mn with Cr can advantageously form
dispersoids. In certain aspects, the alloy has a Cr/Mn weight ratio
of about 0.15-0.6. For example, the Cr/Mn ratio may be 0.15, 0.16,
0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27,
0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38,
0.39, 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49,
0.50, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, or
0.60. In certain aspects, the Cr/Mn ratio promotes appropriate
dispersoids, leading to improved formability, strengthening, and
corrosion resistance.
[0094] In certain aspects, the alloy also includes iron (Fe) in an
amount from about 0.15% to about 0.3% (e.g., from 0.15% to about
0.25%, from 0.18% to 0.25%, from 0.2% to 0.21%, or from 0.15% to
0.22%) based on the total weight of the alloy. For example, the
alloy can include 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%, or 0.30%
Fe. All expressed in wt. %. In certain aspects, the Fe content
reduces the forming of coarse constituent particles.
[0095] In certain aspects, the alloy includes zirconium (Zr) in an
amount up to about 0.2% (e.g., from 0% to 0.2%, from 0.01% to 0.2%,
from 0.01% to 0.15%, from 0.01% to 0.1%, or from 0.02% to 0.09%)
based on the total weight of the alloy. For example, the alloy can
include 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%,
0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%,
0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%,
0.17%, 0.18%, 0.19%, or 0.2% Zr. In certain aspects, Zr is not
present in the alloy (i.e., 0%). All expressed in wt. %.
[0096] In certain aspects, the alloy includes scandium (Sc) in an
amount up to about 0.2% (e.g., from 0% to 0.2%, from 0.01% to 0.2%,
from 0.05% to 0.15%, or from 0.05% to 0.2%) based on the total
weight of the alloy. For example, the alloy can include 0.001%,
0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%,
0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%,
0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%,
0.19%, or 0.2% Sc. In certain examples, Sc is not present in the
alloy (i.e., 0%). All expressed in wt. %.
[0097] In certain aspects, Sc and/or Zr were added to the
above-described compositions to form Al.sub.3Sc, (Al,Si).sub.3Sc,
(Al,Si).sub.3Zr and/or Al.sub.3Zr dispersoids.
[0098] In certain aspects, the alloy includes tin (Sn) in an amount
up to about 0.25% (e.g., from 0% to 0.25%, from 0% to 0.2%, from 0%
to 0.05%, from 0.01% to 0.15%, or from 0.01% to 0.1%) based on the
total weight of the alloy. For example, the alloy can include
0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%,
0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%,
0.09%, 0.1%, 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%. In
certain aspects, Sn is not present in the alloy (i.e., 0%). All
expressed in wt. %.
[0099] In certain aspects, the alloy described herein includes zinc
(Zn) in an amount up to about 0.9% (e.g., from 0.001% to 0.09%,
from 0.004% to 0.9%, from 0.03% to 0.9%, or from 0.06% to 0.1%)
based on the total weight of the alloy. For example, the alloy can
include 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%,
0.008%, 0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%, 0.015%,
0.016%, 0.017%, 0.018%, 0.019%, 0.02%, 0.021%, 0.022%, 0.023%,
0.024%, 0.025%, 0.026%, 0.027%, 0.028%, 0.029%, 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%, 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%, or 0.9% Zn. All expressed in wt. %. In
certain aspects, Zn can benefit forming, including bending and the
reduction of bending anisotropy in plate products.
[0100] In certain aspects, the alloy includes titanium (Ti) in an
amount up to about 0.1% (e.g., from 0.01% to 0.1%) based on the
total weight of the alloy. For example, the alloy can include
0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%,
0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%, 0.015%, 0.016%,
0.017%, 0.018%, 0.019%, 0.02%, 0.021%, 0.022%, 0.023%, 0.024%,
0.025%, 0.026%, 0.027%, 0.028%, 0.029%, 0.03%, 0.031%, 0.032%,
0.033%, 0.034%, 0.035%, 0.036%, 0.037%, 0.038%, 0.039%, 0.04%,
0.05%, 0.051%, 0.052%, 0.053%, 0.054%, 0.055%, 0.056%, 0.057%,
0.058%, 0.059%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.1% Ti. All
expressed in wt. %. In certain aspects, Ti is used as a
grain-refiner agent.
[0101] In certain aspects, the alloy includes nickel (Ni) in an
amount up to about 0.07% (e.g., from 0% to 0.05%, 0.01% to 0.07%,
from 0.03% to 0.034%, from 0.02% to 0.03%, from 0.034 to 0.054%,
from 0.03 to 0.06%, or from 0.001% to 0.06%) based on the total
weight of the alloy. For example, the alloy can include 0.01%,
0.011%, 0.012%, 0.013%, 0.014%, 0.015%, 0.016%, 0.017%, 0.018%,
0.019%, 0.02%, 0.021%, 0.022%, 0.023%, 0.024%, 0.025%, 0.026%,
0.027%, 0.028%, 0.029%, 0.03%, 0.031%, 0.032%, 0.033%, 0.034%,
0.035%, 0.036%, 0.037%, 0.038%, 0.039%, 0.04%, 0.041%, 0.042%,
0.043%, 0.044%, 0.045%, 0.046%, 0.047%, 0.048%, 0.049%, 0.05%,
0.0521%, 0.052%, 0.053%, 0.054%, 0.055%, 0.056%, 0.057%, 0.058%,
0.059%, 0.06%, 0.061%, 0.062%, 0.063%, 0.064%, 0.065%, 0.066%,
0.067%, 0.068%, 0.069%, or 0.07% Ni. In certain aspects, Ni is not
present in the alloy (i.e., 0%). All expressed in wt. %.
[0102] Optionally, the alloy compositions can further include other
minor elements, sometimes referred to as impurities, in amounts of
about 0.05% or below, 0.04% or below, 0.03% or below, 0.02% or
below, or 0.01% or below each. These impurities may include, but
are not limited to, V, Ga, Ca, Hf, Sr, or combinations thereof.
Accordingly, V, Ga, Ca, Hf, or Sr may be present in an alloy 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 certain aspects, the sum of all
impurities does not exceed 0.15% (e.g., 0.1%). All expressed in wt.
%. In certain aspects, the remaining percentage of the alloy is
aluminum.
Aluminum Alloys for Preparing Sheets
[0103] Also described is an aluminum alloy for use in preparing
aluminum sheets. For example, the aluminum alloy can be used to
prepare automotive body sheets. Optionally, a non-limiting example
of such an alloy can have the following elemental composition as
provided in Table 7.
TABLE-US-00007 TABLE 7 Element Weight Percentage (wt. %) Cu 0.5-2.0
Si 0.5-1.5 Mg 0.5-1.5 Cr 0.001-0.25 Mn 0.005-0.40 Fe 0.1-0.3 Zr
0-0.2 Sc 0-0.2 Sn 0-0.25 Zn 0-4.0 Ti 0-0.15 Ni 0-0.1 Others 0-0.05
(each) 0-0.15 (total) Al Remainder
[0104] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 8.
TABLE-US-00008 TABLE 8 Element Weight Percentage (wt. %) Cu 0.5-2.0
Si 0.5-1.35 Mg 0.6-1.5 Cr 0.001-0.18 Mn 0.005-0.4 Fe 0.1-0.3 Zr
0-0.2 Sc 0-0.2 Sn 0-0.25 Zn 0-0.9 Ti 0-0.15 Ni 0-0.07 Others 0-0.05
(each) 0-0.15 (total) Al Remainder
[0105] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 9.
TABLE-US-00009 TABLE 9 Element Weight Percentage (wt. %) Cu 0.6-1.0
Si 0.6-1.35 Mg 0.9-1.3 Cr 0.03-0.15 Mn 0.05-0.4 Fe 0.1-0.3 Zr 0-0.2
Sn 0-0.25 Zn 0-3.5 Ti 0-0.15 Ni 0-0.05 Sc 0-0.2 Others 0-0.05
(each) 0-0.15 (total) Al Remainder
[0106] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 10.
TABLE-US-00010 TABLE 10 Element Weight Percentage (wt. %) Cu
0.6-0.95 Si 0.7-1.25 Mg 0.9-1.25 Cr 0.03-0.1 Mn 0.05-0.35 Fe
0.15-0.25 Zr 0-0.2 Sn 0-0.25 Zn 0.5-3.5 Ti 0-0.15 Ni 0-0.05 Sc
0-0.2 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0107] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 11.
TABLE-US-00011 TABLE 11 Element Weight Percentage (wt. %) Cu
0.6-2.0 Si 0.55-1.35 Mg 0.6-1.35 Cr 0.001-0.18 Mn 0.005-0.40 Fe
0.1-0.3 Zr 0-0.05 Sc 0-0.05 Sn 0-0.05 Zn 0-4.0 Ti 0.005-0.25 Ni
0-0.07 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0108] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 12.
TABLE-US-00012 TABLE 12 Element Weight Percentage (wt. %) Cu
0.65-0.95 Si 0.6-1.35 Mg 0.65-1.28 Cr 0.005-0.12 Mn 0.07-0.36 Fe
0.2-0.26 Zr 0-0.05 Sc 0-0.05 Sn 0-0.05 Zn 0.5-3.1 Ti 0.08-0.14 Ni
0.02-0.06 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0109] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 13.
TABLE-US-00013 TABLE 13 Element Weight Percentage (wt. %) Cu
0.6-0.9 Si 0.7-1.1 Mg 0.9-1.5 Cr 0.06-0.15 Mn 0.05-0.3 Fe 0.1-0.3
Zr 0-0.2 Sc 0-0.2 Sn 0-0.25 Zn 0-0.2 Ti 0-0.15 Ni 0-0.07 Others
0-0.05 (each) 0-0.15 (total) Al Remainder
[0110] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 14.
TABLE-US-00014 TABLE 14 Element Weight Percentage (wt. %) Cu
0.8-1.95 Si 0.6-0.9 Mg 0.8-1.2 Cr 0.06-0.18 Mn 0.005-0.35 Fe
0.13-0.25 Zr 0-0.05 Sc 0-0.05 Sn 0-0.05 Zn 0.5-3.1 Ti 0.01-0.14 Ni
0-0.05 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0111] Another non-limiting example of such an alloy has the
following elemental composition as provided in Table 15.
TABLE-US-00015 TABLE 15 Element Weight Percentage (wt. %) Cu
0.8-1.8 Si 0.6-0.8 Mg 0.9-1.1 Cr 0.08-0.15 Mn 0.01-0.34 Fe
0.15-0.25 Zr 0-0.05 Sc 0-0.05 Sn 0-0.05 Zn 0.5-3.1 Ti 0.01-0.14 Ni
0-0.05 Others 0-0.05 (each) 0-0.15 (total) Al Remainder
[0112] In certain aspects, the alloy includes copper (Cu) in an
amount from about 0.5% to about 2.0% (e.g., from 0.6 to 2.0%, from
0.7 to 0.9%, from 1.35% to 1.95%, from 0.84% to 0.94%, from 1.6% to
1.8%, from 0.78% to 0.92% from 0.75% to 0.85%, or from 0.65% to
0.75%) based on the total weight of the alloy. For example, the
alloy can include 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%, 1.01%,
1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%, 1.09%, 1.1%,
1.11%, 1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19%,
1.2%, 1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%,
1.29%, 1.3%, 1.31%, 1.32%, 1.33%, 1.34%, or 1.35%, 1.36%, 1.37%,
1.38%, 1.39%, 1.4%, 1.41%, 1.42%, 1.43%, 1.44%, 1.45%, 1.46%,
1.47%, 1.48%, 1.49%, 1.5%, 1.51%, 1.52%, 1.53%, 1.54%, 1.55%,
1.56%, 1.57%, 1.58%, 1.59%, 1.6%, 1.61%, 1.62%, 1.63%, 1.64%,
1.65%, 1.66%, 1.67%, 1.68%, 1.69%, 1.7%, 1.71%, 1.72%, 1.73%,
1.74%, 1.75%, 1.76%, 1.77%, 1.78%, 1.79%, 1.8%, 1.81%, 1.82%,
1.83%, 1.84%, 1.85%, 1.86%, 1.87%, 1.88%, 1.89%, 1.9%, 1.91%,
1.92%, 1.93%, 1.94%, 1.95%, 1.96%, 1.97%, 1.98%, 1.99%, or 2.0% Cu.
All expressed in wt. %.
[0113] In certain aspects, the alloy includes silicon (Si) in an
amount from about 0.5% to about 1.5% (e.g., from 0.5% to 1.4%, from
0.55% to 1.35%, from 0.6% to 1.24%, from 1.0% to 1.3%, or from 1.03
to 1.24%) based on the total weight of the alloy. For example, the
alloy can include 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%, 1.01%,
1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%1.08%1.09%, 1.1%, 1.11%,
1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19%, 1.2%,
1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%, 1.29%,
1.3%, 1.31%, 1.32%, 1.33%, 1.34%, 1.35%, 1.36%, 1.37%, 1.38%,
1.39%, 1.4%, 1.41%, 1.42%, 1.43%, 1.44%, 1.45%, 1.46%, 1.47%,
1.48%, 1.49%, or 1.5% Si. All expressed in wt. %.
[0114] In certain aspects, the alloy includes magnesium (Mg) in an
amount from about 0.5% to about 1.5% (e.g., about 0.6% to about
1.35%, about 0.65% to 1.2%, from 0.8% to 1.2%, or from 0.9% to
1.1%) based on the total weight of the alloy. For example, the
alloy can include 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%, 1.01%,
1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%1.09%, 1.1%, 1.11%,
1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19%, 1.2%,
1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%, 1.29%,
1.3%, 1.31%, 1.32%, 1.33%, 1.34%, 1.35%, 1.36%, 1.37%, 1.38%,
1.39%, 1.4%, 1.41%, 1.42%, 1.43%, 1.44%, 1.45%, 1.46%, 1.47%,
1.48%, 1.49%, or 1.5% Mg. All expressed in wt. %.
[0115] In certain aspects, the alloy includes chromium (Cr) in an
amount from about 0.001% to about 0.25% (e.g., from 0.001% to
0.15%, from 0.001% to 0.13%, from 0.005% to 0.12%, from 0.02% to
0.04%, from 0.08% to 0.15%, from 0.03% to 0.045%, from 0.01% to
0.06%, from 0.035% to 0.045%, from 0.004% to 0.08%, from 0.06% to
0.13%, from 0.06% to 0.18%, from 0.1% to 0.13%, or from 0.11% to
0.12%) based on the total weight of the alloy. For example, the
alloy can include 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%,
0.007%, 0.008%, 0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%,
0.015%, 0.02%, 0.025%, 0.03%, 0.035%, 0.04%, 0.045%, 0.05%, 0.055%,
0.06%, 0.065%, 0.07%, 0.075%, 0.08%, 0.085%, 0.09%, 0.095%, 0.1%,
0.105%, 0.11%, 0.115%, 0.12%, 0.125%, 0.13%, 0.135%, 0.14%, 0.145%,
0.15%, 0.155%, 0.16%, 0.165%, 0.17%, 0.175%, 0.18% 0.185%, 0.19%,
0.195%, 0.20%, 0.205%, 0.21%, 0.215%, 0.22%, 0.225%, 0.23%, 0.235%,
0.24%, 0.245%, or 0.25% Cr. All expressed in wt. %.
[0116] In certain aspects, the alloy can include manganese (Mn) in
an amount from about 0.005% to about 0.4% (e.g., from 0.005% to
0.34%, from 0.25% to 0.35%, about 0.03%, from 0.11% to 0.19%, from
0.08% to 0.12%, from 0.12% to 0.18%, from 0.09% to 0.31%, from
0.005% to 0.05%, and from 0.01 to 0.03%) based on the total weight
of the alloy. For example, the alloy can include 0.005%, 0.006%,
0.007%, 0.008%, 0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%,
0.015%, 0.016%, 0.017%, 0.018%, 0.019%, 0.02%, 0.021%, 0.022%,
0.023%, 0.024%, 0.025%, 0.026%, 0.027%, 0.028%, 0.029%, 0.03%,
0.031%, 0.032%, 0.033%, 0.034%, 0.035%, 0.036%, 0.037%, 0.038%,
0.039%, 0.04%, 0.041%, 0.042%, 0.043%, 0.044%, 0.045%, 0.046%,
0.047%, 0.048%, 0.049%, 0.05%, 0.051%, 0.052%, 0.053%, 0.054%,
0.055%, 0.056%, 0.057%, 0.058%, 0.059%, 0.06%, 0.061%, 0.062%,
0.063%, 0.064%, 0.065%, 0.066%, 0.067%, 0.068%, 0.069%, 0.07%,
0.071%, 0.072%, 0.073%, 0.074%, 0.075%, 0.076%, 0.077%, 0.078%,
0.079%, 0.08%, 0.081%, 0.082%, 0.083%, 0.084%, 0.085%, 0.086%,
0.087%, 0.088%, 0.089%, 0.09%, 0.091%, 0.092%, 0.093%, 0.094%,
0.095%, 0.096%, 0.097%, 0.098%, 0.099%, 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% Mn. All
expressed in wt. %.
[0117] In certain aspects, the alloy includes iron (Fe) in an
amount from about 0.1% to about 0.3% (e.g., from 0.15% to 0.25%,
from 0.14% to 0.26%, from 0.13% to 0.27%, from 0.12% to 0.28%, or
from) 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%, or 0.3% Fe. All expressed in wt. %.
[0118] In certain aspects, the alloy includes zirconium (Zr) in an
amount up to about 0.2% (e.g., from 0% to 0.2%, from 0.01% to 0.2%,
from 0.01% to 0.15%, from 0.01% to 0.1%, or from 0.02% to 0.09%)
based on the total weight of the alloy. For example, the alloy can
include 0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%,
0.008%, 0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%,
0.08%, 0.09%, 0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%,
0.17%, 0.18%, 0.19%, or 0.2% Zr. In certain cases, Zr is not
present in the alloy (i.e., 0%). All expressed in wt. %
[0119] In certain aspects, the alloy includes scandium (Sc) in an
amount up to about 0.2% (e.g., from 0% to 0.2%, from 0.01% to 0.2%,
from 0.05% to 0.15%, or from 0.05% to 0.2%) based on the total
weight of the alloy. For example, the alloy can include 0.001%,
0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%, 0.009%,
0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%,
0.1%, 0.11%, 0.12%, 0.13%, 0.14%, 0.15%, 0.16%, 0.17%, 0.18%,
0.19%, or 0.2% Sc. In certain cases, Sc is not present in the alloy
(i.e., 0%). All expressed in wt. %.
[0120] In certain aspects, the alloy includes zinc (Zn) in an
amount up to about 4.0% (e.g., from 0.001% to 0.09%, from 0.4% to
3.0%, from 0.03% to 0.3%, from 0% to 1.0%, from 1.0% to 2.5%, or
from 0.06% to 0.1%) based on the total weight of the alloy. For
example, the alloy can include 0.001%, 0.002%, 0.003%, 0.004%,
0.005%, 0.006%, 0.007%, 0.008%, 0.009%, 0.01%, 0.011%, 0.012%,
0.013%, 0.014%, 0.015%, 0.016%, 0.017%, 0.018%, 0.019%, 0.02%,
0.021%, 0.022%, 0.023%, 0.024%, 0.025%, 0.026%, 0.027%, 0.028%,
0.029%, 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%, 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%, 1.01%,
1.02%, 1.03%, 1.04%, 1.05%, 1.06%, 1.07%, 1.08%, 1.09%, 1.1%,
1.11%, 1.12%, 1.13%, 1.14%, 1.15%, 1.16%, 1.17%, 1.18%, 1.19%,
1.2%, 1.21%, 1.22%, 1.23%, 1.24%, 1.25%, 1.26%, 1.27%, 1.28%,
1.29%, 1.3%, 1.31%, 1.32%, 1.33%, 1.34%, or 1.35%, 1.36%, 1.37%,
1.38%, 1.39%, 1.4%, 1.41%, 1.42%, 1.43%, 1.44%, 1.45%, 1.46%,
1.47%, 1.48%, 1.49%, 1.5%, 1.51%, 1.52%, 1.53%, 1.54%, 1.55%,
1.56%, 1.57%, 1.58%, 1.59%, 1.6%, 1.61%, 1.62%, 1.63%, 1.64%,
1.65%, 1.66%, 1.67%, 1.68%, 1.69%, 1.7%, 1.71%, 1.72%, 1.73%,
1.74%, 1.75%, 1.76%, %, 1.77%, 1.78%, 1.79%, 1.8%, 1.81%, 1.82%,
1.83%, 1.84%, 1.85%, 1.86%, 1.87%, 1.88%, 1.89%, 1.9%, 1.91%,
1.92%, 1.93%, 1.94%, 1.95%, 1.96%, 1.97%, 1.98%, 1.99%, 2.0%,
2.01%, 2.02%, 2.03%, 2.04%, 2.05%, 2.06%, 2.07%, 2.08%, 2.09%,
2.1%, 2.11%, 2.12%, 2.13%, 2.14%, 2.15%, 2.16%, 2.17%, 2.18%,
2.19%, 2.2%, 2.21%, 2.22%, 2.23%, 2.24%, 2.25%, 2.26%, 2.27%,
2.28%, 2.29%, 2.3%, 2.31%, 2.32%, 2.33%, 2.34%, 2.35%, 2.36%,
2.37%, 2.38%, 2.39%, 2.4%, 2.41%, 2.42%, 2.43%, 2.44%, 2.45%,
2.46%, 2.47%, 2.48%, 2.49%, 2.5%, 2.51%, 2.52%, 2.53%, 2.54%,
2.55%, 2.56%, 2.57%, 2.58%, 2.59%, 2.6%, 2.61%, 2.62%, 2.63%,
2.64%, 2.65%, 2.66%, 2.67%, 2.68%, 2.69%, 2.7%, 2.71%, 2.72%,
2.73%, 2.74%, 2.75%, 2.76%, 2.77%, 2.78%, 2.79%, 2.8%, 2.81%,
2.82%, 2.83%, 2.84%, 2.85%, 2.86%, 2.87%, 2.88%, 2.89%, 2.9%,
2.91%, 2.92%, 2.93%, 2.94%, 2.95%, 2.96%, 2.97%, 2.98%, 2.99%,
3.0%, 3.01%, 3.02%, 3.03%, 3.04%, 3.05%, 3.06%, 3.07%, 3.08%,
3.09%, 3.1%, 3.11%, 3.12%, 3.13%, 3.14%, 3.15%, 3.16%, 3.17%,
3.18%, 3.19%, 3.2%, 3.21%, 3.22%, 3.23%, 3.24%, 3.25%, 3.26%,
3.27%, 3.28%, 3.29%, 3.3%, 3.31%, 3.32%, 3.33%, 3.34%, 3.35%,
3.36%, 3.37%, 3.38%, 3.39%, 3.4%, 3.41%, 3.42%, 3.43%, 3.44%,
3.45%, 3.46%, 3.47%, 3.48%, 3.49%, 3.5%, 3.51%, 3.52%, 3.53%,
3.54%, 3.55%, 3.56%, 3.57%, 3.58%, 3.59%, 3.6%, 3.61%, 3.62%,
3.63%, 3.64%, 3.65%, 3.66%, 3.67%, 3.68%, 3.69%, 3.7%, 3.71%,
3.72%, 3.73%, 3.74%, 3.75%, 3.76%, 3.77%, 3.78%, 3.79%, 3.8%,
3.81%, 3.82%, 3.83%, 3.84%, 3.85%, 3.86%, 3.87%, 3.88%, 3.89%,
3.9%, 3.91%, 3.92%, 3.93%, 3.94%, 3.95%, 3.96%, 3.97%, 3.98%,
3.99%, or 4.0% Zn. In certain cases, Zn is not present in the alloy
(i.e., 0%). All expressed in wt. %.
[0121] In certain aspects, the alloy includes tin (Sn) in an amount
up to about 0.25% (e.g., from 0% to 0.25%, from 0% to 0.2%, from 0%
to 0.05%, from 0.01% to 0.15%, or from 0.01% to 0.1%) based on the
total weight of the alloy. For example, the alloy can include
0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%,
0.009%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%,
0.09%, 0.1%, 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%. In
certain cases, Sn is not present in the alloy (i.e., 0%). All
expressed in wt. %.
[0122] In certain aspects, the alloy includes titanium (Ti) in an
amount up to about 0.15% (e.g., from 0.01% to 0.1%) based on the
total weight of the alloy. For example, the alloy can include
0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%,
0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%, 0.015%, 0.016%,
0.017%, 0.018%, 0.019%, 0.02%, 0.021%, 0.022%, 0.023%, 0.024%,
0.025%, 0.026%, 0.027%, 0.028%, 0.029%, 0.03%, 0.031%, 0.032%,
0.033%, 0.034%, 0.035%, 0.036%, 0.037%, 0.038%, 0.039%, 0.04%,
0.05%, 0.051%, 0.052%, 0.053%, 0.054%, 0.055%, 0.056%, 0.057%,
0.058%, 0.059%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.11%, 0.12%,
0.13%, 0.14%, or 0.15% Ti. All expressed in wt. %.
[0123] In certain aspects, the alloy includes nickel (Ni) in an
amount up to about 0.1% (e.g., from 0.01% to 0.1%) based on the
total weight of the alloy. For example, the alloy can include
0.001%, 0.002%, 0.003%, 0.004%, 0.005%, 0.006%, 0.007%, 0.008%,
0.009%, 0.01%, 0.011%, 0.012%, 0.013%, 0.014%, 0.015%, 0.016%,
0.017%, 0.018%, 0.019%, 0.02%, 0.021%, 0.022%, 0.023%, 0.024%,
0.025%, 0.026%, 0.027%, 0.028%, 0.029%, 0.03%, 0.031%, 0.032%,
0.033%, 0.034%, 0.035%, 0.036%, 0.037%, 0.038%, 0.039%, 0.04%,
0.05%, 0.051%, 0.052%, 0.053%, 0.054%, 0.055%, 0.056%, 0.057%,
0.058%, 0.059%, 0.06%, 0.07%, 0.08%, 0.09%, or 0.1% Ni. In certain
aspects, Ni is not present in the alloy (i.e., 0%). All expressed
in wt. %.
[0124] Optionally, the alloy compositions described herein can
further include other minor elements, sometimes referred to as
impurities, in amounts of about 0.05% or below, 0.04% or below,
0.03% or below, 0.02% or below, or 0.01% or below each. These
impurities may include, but are not limited to, V, Ga, Ca, Hf, Sr,
or combinations thereof. Accordingly, V, Ga, Ca, Hf, or Sr may be
present in an alloy 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 certain
examples, the sum of all impurities does not exceed about 0.15%
(e.g., 0.1%). All expressed in wt. %. In certain examples, the
remaining percentage of the alloy is aluminum.
[0125] An exemplary alloy includes 1.03% Si, 0.22% Fe, 0.66% Cu,
0.14% Mn, 1.07% Mg, 0.025 Ti, 0.06% Cr, and up to 0.15% total
impurities, with the remainder Al.
[0126] Another exemplary alloy includes 1.24% Si, 0.22% Fe, 0.81%
Cu, 0.11% Mn, 1.08% Mg, 0.024% Ti, 0.073% Cr, and up to 0.15% total
impurities, with the remainder Al.
[0127] Another exemplary alloy includes 1.19% Si, 0.16% Fe, 0.66%
Cu, 0.17% Mn, 1.16% Mg, 0.02% Ti, 0.03% Cr, and up to 0.15% total
impurities, with the remainder Al.
[0128] Another exemplary alloy includes 0.97% Si, 0.18% Fe, 0.80%
Cu, 0.19% Mn, 1.11% Mg, 0.02% Ti, 0.03% Cr, and up to 0.15% total
impurities, with the remainder Al.
[0129] Another exemplary alloy includes 1.09% Si, 0.18% Fe, 0.61%
Cu, 0.18% Mn, 1.20% Mg, 0.02% Ti, 0.03% Cr, and up to 0.15% total
impurities, with the remainder Al.
[0130] Another exemplary alloy includes 0.76% Si, 0.22% Fe, 0.91%
Cu, 0.32% Mn, 0.94% Mg, 0.12% Ti, 3.09% Zn, and up to 0.15% total
impurities, with the remainder Al.
Alloy Properties
[0131] In some non-limiting examples, the disclosed alloys have
very high formability and bendability in the T4 temper and very
high strength and good corrosion resistance in the T6 temper
compared to conventional 6XXX series alloys. In certain cases, the
alloys also demonstrate very good anodized qualities.
[0132] In certain aspects, the aluminum alloy may have an
in-service strength (strength on a vehicle) of at least about 340
MPa. In non-limiting examples, the in-service strength is at least
about 350 MPa, at least about 360 MPa, at least about 370 MPa, at
least about 380 MPa, at least about 390 MPa, at least about 395
MPa, at least about 400 MPa, at least about 410 MPa, at least about
420 MPa, at least about 430 MPa, or at least about 440 MPa, at
least about 450 MPa, at least about 460 MPa, at least about 470
MPa, at least about 480 MPa, at least about 490 MPa, at least about
495 MPa, or at least about 500 MPa. In some cases, the in-service
strength is from about 340 MPa to about 500 MPa. For example, the
in-service strength can be from about 350 MPa to about 495 MPa,
from about 375 MPa to about 475 MPa, from about 400 MPa to about
450 MPa, from about 380 MPa to about 390 MPa, or from about 385 MPa
to about 395 MPa.
[0133] In certain aspects, the alloy encompasses any in-service
strength that has sufficient ductility or toughness to meet a R/t
bendability of about 1.3 or less in the T4 temper (e.g., 1.0 or
less). In certain examples, the R/t bendability is about 1.2 or
less, 1.1 or less, 1.0 or less, 0.8 or less, 0.7 or less, 0.6 or
less, 0.5 or less, or 0.4 or less, where R is the radius of the
tool (die) used and t is the thickness of the material.
[0134] In certain aspects, the alloy provides a bendability in
thinner gauge alloy sheets showing a bend angle of less than
95.degree. in T4 temper and less than 140.degree. in T6 temper. In
some non-limiting examples the bend angle of alloy sheets in T4
temper can be at least 90.degree., 85.degree., 80.degree.,
75.degree., 70.degree., 65.degree., 60.degree., 55.degree.,
50.degree., 45.degree., 40.degree., 35.degree., 30.degree.,
25.degree., 20.degree., 15.degree., 10.degree., 5.degree., or
1.degree.. In some non-limiting examples, the bend angle of alloy
sheets in T6 temper can be at least 135.degree., 130.degree.,
125.degree., 120.degree., 115.degree., 110.degree., 105.degree.,
100.degree., 95.degree., 90.degree., 85.degree., 80.degree.,
75.degree., 70.degree., 65.degree., 60.degree., 55.degree.,
50.degree., 45.degree., 40.degree., 35.degree., 30.degree.,
25.degree., 20.degree., 15.degree., 10.degree., 5.degree., or
1.degree..
[0135] In certain aspects, the alloy provides a uniform elongation
of greater than or equal to 20% and a total elongation of greater
than or equal to 25%. In certain aspects, the alloy provides a
uniform elongation of greater than or equal to 22% and a total
elongation of greater than or equal to 27%.
[0136] In certain aspects, the alloy may have a corrosion
resistance that provides an intergranular corrosion (IGC) attack
depth of 200 .mu.m or less under the ASTM G110 standard. In certain
cases, the IGC corrosion attack depth is 190 .mu.m or less, 180
.mu.m or less, 170 .mu.m or less, 160 .mu.m or less, or even 150
.mu.m or less. In some further examples, the alloy may have a
corrosion resistance that provides an IGC attack depth of 300 .mu.m
or less for thicker gauge shates and 350 .mu.m or less for thinner
gauge sheets under the ISO 11846 standard. In certain cases, the
IGC corrosion attack depth is 290 .mu.m or less, 280 .mu.m or less,
270 .mu.m or less, 260 .mu.m or less, 250 .mu.m or less, 240 .mu.m
or less, 230 .mu.m or less, 220 .mu.m or less, 210 .mu.m or less,
200 .mu.m or less, 190 .mu.m or less, 180 .mu.m or less, 170 .mu.m
or less, 160 .mu.m or less, or even 150 .mu.m or less for alloy
shates. In certain cases, the IGC corrosion attack depth is 340
.mu.m or less, 330 .mu.m or less, 320 .mu.m or less, 310 .mu.m or
less, 300 .mu.m or less, 290 .mu.m or less, 280 .mu.m or less, 270
.mu.m or less, 260 .mu.m or less, 250 .mu.m or less, 240 .mu.m or
less, 230 .mu.m or less, 220 .mu.m or less, 210 .mu.m or less, 200
.mu.m or less, 190 .mu.m or less, 180 .mu.m or less, 170 .mu.m or
less, 160 .mu.m or less, or even 150 .mu.m or less for alloy
sheets.
[0137] The mechanical properties of the aluminum alloy may be
controlled by various aging conditions depending on the desired
use. As one example, the alloy can be produced (or provided) in the
T4 temper or the T6 temper or the T8 temper. T4 plates, shates
(i.e., sheet plates), or sheets, which refer to plates, shates, or
sheets that are solution heat-treated and naturally aged, can be
provided. These T4 plates, shates, and sheets can optionally be
subjected to additional aging treatment(s) to meet strength
requirements upon receipt. For example, plates, shates, and sheets
can be delivered in other tempers, such as the T6 temper or the T8
temper, by subjecting the T4 alloy material to the appropriate
aging treatment as described herein or otherwise known to those of
skill in the art.
Methods of Preparing the Plates and Shates
[0138] In certain aspects, the disclosed alloy composition is a
product of a disclosed method. Without intending to limit the
invention, aluminum alloy properties are partially determined by
the formation of microstructures during the alloy's preparation. In
certain aspects, the method of preparation for an alloy composition
may influence or even determine whether the alloy will have
properties adequate for a desired application.
[0139] The alloy described herein can be cast using a casting
method as known to those of skill in the art. For example, the
casting process can include a Direct Chill (DC) casting process.
The DC casting process is performed according to standards commonly
used in the aluminum industry as known to one of skill in the art.
Optionally, the casting process can include a continuous casting
(CC) process. The cast product can then be subjected to further
processing steps. In one non-limiting example, the processing
method includes homogenization, hot rolling, solutionization, and
quenching. In some cases, the processing steps further include
annealing and/or cold rolling if desired.
Homogenization
[0140] The homogenization step can include heating an ingot
prepared from an alloy composition described herein to attain a
peak metal temperature (PMT) of about, or at least about,
520.degree. C. (e.g., at least 520.degree. C., at least 530.degree.
C., at least 540.degree. C., at least 550.degree. C., at least
560.degree. C., at least 570.degree. C., or at least 580.degree.
C.). For example, the ingot can be heated to a temperature of from
about 520.degree. C. to about 580.degree. C., from about
530.degree. C. to about 575.degree. C., from about 535.degree. C.
to about 570.degree. C., from about 540.degree. C. to about
565.degree. C., from about 545.degree. C. to about 560.degree. C.,
from about 530.degree. C. to about 560.degree. C., or from about
550.degree. C. to about 580.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., about
10.degree. C./min to about 90.degree. C./min, about 10.degree.
C./min to about 70.degree. C./min, 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).
[0141] The ingot is then allowed to soak (i.e., held at the
indicated temperature) for a period of time. According to one
non-limiting example, the ingot is allowed to soak for up to about
6 hours (e.g., from about 30 minutes to about 6 hours,
inclusively). For example, the ingot can be soaked at a temperature
of at least 500.degree. C. for 30 minutes, 1 hour, 2 hours, 3
hours, 4 hours, 5 hours, or 6 hours, or anywhere in between.
Hot Rolling
[0142] Following the homogenization step, a hot rolling step can be
performed. In certain cases, the ingots are laid down and
hot-rolled with an entry temperature range of about 500.degree. C.
540.degree. C. The entry temperature can be, for example, about
505.degree. C., 510.degree. C., 515.degree. C., 520.degree. C.,
525.degree. C., 530.degree. C., 535.degree. C., or 540.degree. C.
In certain cases, the hot roll exit temperature can range from
about 250.degree. C. 380.degree. C. (e.g., from about 330.degree.
C. 370.degree. C.). For example, the hot roll exit temperature can
be about 255.degree. C., 260.degree. C., 265.degree. C.,
270.degree. C., 275.degree. C., 280.degree. C., 285.degree. C.,
290.degree. C., 295.degree. C., 300.degree. C., 305.degree. C.,
310.degree. C., 315.degree. C., 320.degree. C., 325.degree. C.,
330.degree. C., 335.degree. C., 340.degree. C., 345.degree. C.,
350.degree. C., 355.degree. C., 360.degree. C., 365.degree. C.,
370.degree. C., 375.degree. C., or 380.degree. C.
[0143] In certain cases, the ingot can be hot rolled to an about 4
mm to about 15 mm thick gauge (e.g., from about 5 mm to about 12 mm
thick gauge), which is referred to as a shate. For example, the
ingot can be hot rolled to an about 4 mm thick gauge, about 5 mm
thick gauge, about 6 mm thick gauge, about 7 mm thick gauge, about
8 mm thick gauge, about 9 mm thick gauge, about 10 mm thick gauge,
about 11 mm thick gauge, about 12 mm thick gauge, about 13 mm thick
gauge, about 14 mm thick gauge, or about 15 mm thick gauge. In
certain cases, the ingot can be hot rolled to a gauge greater than
15 mm thick (i.e., a plate). In other cases, the ingot can be hot
rolled to a gauge less than 4 mm (i.e., a sheet). The temper of the
as-rolled plates, shates and sheets is referred to as F-temper.
Optional Processing Steps: Annealing Step and Cold Rolling Step
[0144] In certain aspects, the alloy undergoes further processing
steps after the hot rolling step and before any subsequent steps
(e.g., before a solutionizing step). Further process steps may
include an annealing procedure and a cold rolling step.
[0145] The annealing step can result in an alloy with improved
texture (e.g., an improved T4 alloy) with reduced anisotropy during
forming operations, such as stamping, drawing, or bending. By
applying the annealing step, the texture in the modified temper is
controlled/engineered to be more random and to reduce those texture
components (TCs) that can yield strong formability anisotropy
(e.g., Goss, Goss-ND, or Cube-RD). This improved texture can
potentially reduce the bending anisotropy and can improve the
formability in the forming where a drawing or circumferential
stamping process is involved, as it acts to reduce the variability
in properties at different directions.
[0146] The annealing step can include heating the alloy from room
temperature to a temperature from about 400.degree. C. to about
500.degree. C. (e.g., from about 405.degree. C. to about
495.degree. C., from about 410.degree. C. to about 490.degree. C.,
from about 415.degree. C. to about 485.degree. C., from about
420.degree. C. to about 480.degree. C., from about 425.degree. C.
to about 475.degree. C., from about 430.degree. C. to about
470.degree. C., from about 435.degree. C. to about 465.degree. C.,
from about 440.degree. C. to about 460.degree. C., from about
445.degree. C. to about 455.degree. C., from about 450.degree. C.
to about 460.degree. C., from about 400.degree. C. to about
450.degree. C., from about 425.degree. C. to about 475.degree. C.,
or from about 450.degree. C. to about 500.degree. C.).
[0147] The plate or shate can soak at the temperature for a period
of time. In one non-limiting example, the plate or shate is allowed
to soak for up to approximately 2 hours (e.g., from about 15 to
about 120 minutes, inclusively). For example, the plate or shate
can be soaked at the temperature of from about 400.degree. C. to
about 500.degree. C. for 15 minutes, 20 minutes, 25 minutes, 30
minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55
minutes, 60 minutes, 65 minutes, 70 minutes, 75 minutes, 80
minutes, 85 minutes, 90 minutes, 95 minutes, 100 minutes, 105
minutes, 110 minutes, 115 minutes, or 120 minutes, or anywhere in
between.
[0148] In certain aspects, the alloy does not undergo an annealing
step.
[0149] A cold rolling step can optionally be applied to the alloy
before the solutionizing step. In certain aspects, the rolled
product from the hot rolling step (e.g., the plate or shate) can be
cold rolled to a thin gauge shate (e.g., about 4.0 to 4.5 mm). In
certain aspects, the rolled product is cold rolled to about 4.0,
about 4.1 mm, about 4.2 mm, about 4.3 mm, about 4.4 mm, or about
4.5 mm.
Solutionizing
[0150] The solutionizing step can include heating the plate or
shate from room temperature to a temperature of from about
520.degree. C. to about 590.degree. C. (e.g., from about
520.degree. C. to about 580.degree. C., from about 530.degree. C.
to about 570.degree. C., from about 545.degree. C. to about
575.degree. C., from about 550.degree. C. to about 570.degree. C.,
from about 555.degree. C. to about 565.degree. C., from about
540.degree. C. to about 560.degree. C., from about 560.degree. C.
to about 580.degree. C., or from about 550.degree. C. to about
575.degree. C.). The plate or shate can soak at the temperature for
a period of time. In certain aspects, the plate or shate is allowed
to soak for up to approximately 2 hours (e.g., from about 10
seconds to about 120 minutes inclusively). For example, the plate
or shate can be soaked at the temperature of from about 525.degree.
C. to about 590.degree. C. for 20 seconds, 25 seconds, 30 seconds,
35 seconds, 40 seconds, 45 seconds, 50 seconds, 55 seconds, 60
seconds, 65 seconds, 70 seconds, 75 seconds, 80 seconds, 85
seconds, 90 seconds, 95 seconds, 100 seconds, 105 seconds, 110
seconds, 115 seconds, 120 seconds, 125 seconds, 130 seconds, 135
seconds, 140 seconds, 145 seconds, or 150 seconds, 5 minutes, 10
minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35
minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60
minutes, 65 minutes, 70 minutes, 75 minutes, 80 minutes, 85
minutes, 90 minutes, 95 minutes, 100 minutes, 105 minutes, 110
minutes, 115 minutes, or 120 minutes, or anywhere in between.
[0151] In certain aspects, the heat treatment is performed
immediately after the hot or cold rolling step. In certain aspects,
the heat treatment is performed after an annealing step.
Quenching
[0152] In certain aspects, the plate or shate can then be cooled to
a temperature of about 25.degree. C. at a quench speed that can
vary between about 50.degree. C./s to 400.degree. C./s in a
quenching step that is based on the selected gauge. For example,
the quench rate can be from about 50.degree. C./s to about
375.degree. C./s, from about 60.degree. C./s to about 375.degree.
C./s, from about 70.degree. C./s to about 350.degree. C./s, from
about 80.degree. C./s to about 325.degree. C./s, from about
90.degree. C./s to about 300.degree. C./s, from about 100.degree.
C./s to about 275.degree. C./s, from about 125.degree. C./s to
about 250.degree. C./s, from about 150.degree. C./s to about
225.degree. C./s, or from about 175.degree. C./s to about
200.degree. C./s.
[0153] In the quenching step, the plate or shate is rapidly
quenched with a liquid (e.g., water) and/or gas or another selected
quench medium. In certain aspects, the plate or shate can be
rapidly quenched with water. In certain aspects, the plate or shate
is quenched with air.
Aging
[0154] The plate or shate can be naturally aged for a period of
time to result in the T4 temper. In certain aspects, the plate or
shate in the T4 temper can be artificially aged (AA) at about
180.degree. C. to 225.degree. C. (e.g., 185.degree. C., 190.degree.
C., 195.degree. C., 200.degree. C., 205.degree. C., 210.degree. C.,
215.degree. C., 220.degree. C., or 225.degree. C.) for a period of
time. Optionally, the plate or shate can be artificially aged for a
period from about 15 minutes to about 8 hours (e.g., 15 minutes, 30
minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7
hours, or 8 hours or anywhere in between) to result in the T6
temper.
Coil Production
[0155] In certain aspects, the annealing step during production can
also be applied to produce the plate or shate material in a coil
form for improved productivity or formability. For example, an
alloy in coil form can be supplied in the O temper, using a hot or
cold rolling step and an annealing step following the hot or cold
rolling step. Forming may occur in O temper, which is followed by
solution heat treatment, quenching and artificial aging/paint
baking.
[0156] In certain aspects, to produce a plate or shate in coil form
and with high formability compared to F temper, an annealing step
as described herein can be applied to the coil. Without intending
to limit the invention, the purpose for the annealing and the
annealing parameters may include (1) releasing the work-hardening
in the material to gain formability; (2) recrystallizing or
recovering the material without causing significant grain growth;
(3) engineering or converting texture to be appropriate for forming
and for reducing anisotropy during formability; and (4) avoiding
the coarsening of pre-existing precipitation particles.
Methods of Preparing the Sheets
[0157] In certain aspects, the disclosed alloy composition is a
product of a disclosed method. Without intending to limit the
invention, aluminum alloy properties are partially determined by
the formation of microstructures during the alloy's preparation. In
certain aspects, the method of preparation for an alloy composition
may influence or even determine whether the alloy will have
properties adequate for a desired application.
[0158] The alloy described herein can be cast using a casting
method as known to those of skill in the art. For example, the
casting process can include a Direct Chill (DC) casting process.
The DC casting process is performed according to standards commonly
used in the aluminum industry as known to one of skill in the art.
Optionally, the casting process can include a continuous casting
(CC) process. The cast product can then be subjected to further
processing steps. In one non-limiting example, the processing
method includes homogenization, hot rolling, cold rolling, solution
heat treatment, and quenching.
Homogenization
[0159] The homogenization step can involve a one-step
homogenization or a two-step homogenization. In one example of the
homogenization step, a one-step homogenization is performed where
an ingot prepared from an alloy composition described herein is
heated to attain a PMT of about, or at least about, 520.degree. C.
(e.g., at least 520.degree. C., at least 530.degree. C., at least
540.degree. C., at least 550.degree. C., at least 560.degree. C.,
at least 570.degree. C., or at least 580.degree. C.). For example,
the ingot can be heated to a temperature of from about 520.degree.
C. to about 580.degree. C., from about 530.degree. C. to about
575.degree. C., from about 535.degree. C. to about 570.degree. C.,
from about 540.degree. C. to about 565.degree. C., from about
545.degree. C. to about 560.degree. C., from about 530.degree. C.
to about 560.degree. C., or from about 550.degree. C. to about
580.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, 15.degree. C./hour or less, or 10.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., about
10.degree. C./min to about 90.degree. C./min, about 10.degree.
C./min to about 70.degree. C./min, 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).
[0160] The ingot is then allowed to soak (i.e., held at the
indicated temperature) for a period of time. According to one
non-limiting example, the ingot is allowed to soak for up to about
8 hours (e.g., from about 30 minutes to about 8 hours,
inclusively). For example, the ingot can be soaked at a temperature
of at least 500.degree. C. for 30 minutes, 1 hour, 2 hours, 3
hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, or anywhere in
between.
[0161] In another example of the homogenization step, a two-step
homogenization is performed where an ingot prepared from an alloy
composition described herein is heated to attain a first
temperature of about, or at least about, 480.degree. C. to about
520.degree. C. For example, the ingot can be heated to a first
temperature of about 480.degree. C., 490.degree. C., 500.degree.
C., 510.degree. C., or 520.degree. C. In certain aspects, the
heating rate to the first temperature can be from about 10.degree.
C./min to about 100.degree. C./min (e.g., about 10.degree. C./min
to about 90.degree. C./min, about 10.degree. C./min to about
70.degree. C./min, 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). In other aspects,
the heating rate to the first temperature can be from about
10.degree. C./hour to about 100.degree. C./hour (e.g., about
10.degree. C./hour to about 90.degree. C./hour, about 10.degree.
C./hour to about 70.degree. C./hour, about 10.degree. C./hour to
about 60.degree. C./hour, from about 20.degree. C./hour to about
90.degree. C./hour, from about 30.degree. C./hour to about
80.degree. C./hour, from about 40.degree. C./hour to about
70.degree. C./hour, or from about 50.degree. C./hour to about
60.degree. C./hour).
[0162] The ingot is then allowed to soak for a period of time. In
certain cases, the ingot is allowed to soak for up to about 6 hours
(e.g., from 30 minutes to 6 hours, inclusively). For example, the
ingot can be soaked at a temperature of from about 480.degree. C.
to about 520.degree. C. for 30 minutes, 1 hour, 2 hours, 3 hours, 4
hours, 5 hours, or 6 hours, or anywhere in between.
[0163] In the second step of the two-step homogenization process,
the ingot can be further heated from the first temperature to a
second temperature of greater than about 520.degree. C. (e.g.,
greater than 520.degree. C., greater than 530.degree. C., greater
than 540.degree. C., greater than 550.degree. C., greater than
560.degree. C., greater than 570.degree. C., or greater than
580.degree. C.). For example, the ingot can be heated to a second
temperature of from about 520.degree. C. to about 580.degree. C.,
from about 530.degree. C. to about 575.degree. C., from about
535.degree. C. to about 570.degree. C., from about 540.degree. C.
to about 565.degree. C., from about 545.degree. C. to about
560.degree. C., from about 530.degree. C. to about 560.degree. C.,
or from about 550.degree. C. to about 580.degree. C. The heating
rate to the second temperature can be from about 10.degree. C./min
to about 100.degree. C./min (e.g., 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 10.degree. C./min to about 90.degree.
C./min, about 10.degree. C./min to about 70.degree. C./min, about
10.degree. C./min to about 60.degree. C./min, 40.degree. C./min to
about 70.degree. C./min, or from about 50.degree. C./min to about
60.degree. C./min).
[0164] In other aspects, the heating rate to the second temperature
can be from about 10.degree. C./hour to about 100.degree. C./hour
(e.g., about 10.degree. C./hour to about 90.degree. C./hour, about
10.degree. C./hour to about 70.degree. C./hour, about 10.degree.
C./hour to about 60.degree. C./hour, from about 20.degree. C./hour
to about 90.degree. C./hour, from about 30.degree. C./hour to about
80.degree. C./hour, from about 40.degree. C./hour to about
70.degree. C./hour, or from about 50.degree. C./hour to about
60.degree. C./hour).
[0165] The ingot is then allowed to soak for a period of time. In
certain cases, the ingot is allowed to soak for up to about 6 hours
(e.g., from 30 minutes to 6 hours, inclusively). For example, the
ingot can be soaked at a temperature of from about 520.degree. C.
to about 580.degree. C. for 30 minutes, 1 hour, 2 hours, 3 hours, 4
hours, 5 hours, or 6 hours, or anywhere in between.
Hot Rolling
[0166] Following the homogenization step, a hot rolling step can be
performed. In certain cases, the ingots are laid down and
hot-rolled with an entry temperature range of about 500.degree. C.
540.degree. C. For example, the entry temperature can be, for
example, about 505.degree. C., 510.degree. C., 515.degree. C.,
520.degree. C., 525.degree. C., 530.degree. C., 535.degree. C., or
540.degree. C. In certain cases, the hot roll exit temperature can
range from about 250.degree. C. to about 380.degree. C. (e.g., from
about 330.degree. C. to about 370.degree. C.). For example, the hot
roll exit temperature can be about 255.degree. C., 260.degree. C.,
265.degree. C., 270.degree. C., 275.degree. C., 280.degree. C.,
285.degree. C., 290.degree. C., 295.degree. C., 300.degree. C.,
305.degree. C., 310.degree. C., 315.degree. C., 320.degree. C.,
325.degree. C., 330.degree. C., 335.degree. C., 340.degree. C.,
345.degree. C., 350.degree. C., 355.degree. C., 360.degree. C.,
365.degree. C., 370.degree. C., 375.degree. C., or 380.degree.
C.
[0167] In certain cases, the ingot can be hot rolled to an about 4
mm to about 15 mm thick gauge (e.g., from about 5 mm to about 12 mm
thick gauge), which is referred to as a shate. For example, the
ingot can be hot rolled to an about 4 mm thick gauge, about 5 mm
thick gauge, about 6 mm thick gauge, about 7 mm thick gauge, about
8 mm thick gauge, about 9 mm thick gauge, about 10 mm thick gauge,
about 11 mm thick gauge, about 12 mm thick gauge, about 13 mm thick
gauge, about 14 mm thick gauge, or about 15 mm thick gauge. In
certain cases, the ingot can be hot rolled to a gauge greater than
15 mm thick (i.e., a plate). In other cases, the ingot can be hot
rolled to a gauge less than 4 mm (i.e., a sheet).
Cold Rolling Step
[0168] A cold rolling step can be performed following the hot
rolling step. In certain aspects, the rolled product from the hot
rolling step can be cold rolled to a sheet (e.g., below
approximately 4.0 mm). In certain aspects, the rolled product is
cold rolled to a thickness of about 0.4 mm to 1.0 mm, 1.0 mm to 3.0
mm, or 3.0 mm to less than 4.0 mm. In certain aspects, the alloy is
cold rolled to about 3.5 mm or less, 3 mm or less, 2.5 mm or less,
2 mm or less, 1.5 mm or less, 1 mm or less, or 0.5 mm or less. For
example, the rolled product can be cold rolled to about 0.1 mm, 0.2
mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm,
1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9
mm, 2.0 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm,
2.8 mm, 2.9 mm, or 3.0 mm.
Solution Heat Treatment
[0169] The solution heat treatment (SHT) step can include heating
the sheet from room temperature to a temperature of from about
520.degree. C. to about 590.degree. C. (e.g., from about
520.degree. C. to about 580.degree. C., from about 530.degree. C.
to about 570.degree. C., from about 545.degree. C. to about
575.degree. C., from about 550.degree. C. to about 570.degree. C.,
from about 555.degree. C. to about 565.degree. C., from about
540.degree. C. to about 560.degree. C., from about 560.degree. C.
to about 580.degree. C., or from about 550.degree. C. to about
575.degree. C.). The sheet can soak at the temperature for a period
of time. In certain aspects, the sheet is allowed to soak for up to
approximately 2 hours (e.g., from about 10 seconds to about 120
minutes inclusively). For example, the sheet can be soaked at the
temperature of from about 525.degree. C. to about 590.degree. C.
for 20 seconds, 25 seconds, 30 seconds, 35 seconds, 40 seconds, 45
seconds, 50 seconds, 55 seconds, 60 seconds, 65 seconds, 70
seconds, 75 seconds, 80 seconds, 85 seconds, 90 seconds, 95
seconds, 100 seconds, 105 seconds, 110 seconds, 115 seconds, 120
seconds, 125 seconds, 130 seconds, 135 seconds, 140 seconds, 145
seconds, or 150 seconds, 5 minutes, 10 minutes, 15 minutes, 20
minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45
minutes, 50 minutes, 55 minutes, 60 minutes, 65 minutes, 70
minutes, 75 minutes, 80 minutes, 85 minutes, 90 minutes, 95
minutes, 100 minutes, 105 minutes, 110 minutes, 115 minutes, or 120
minutes, or anywhere in between.
Quenching
[0170] In certain aspects, the sheet can then be cooled to a
temperature of about 25.degree. C. at a quench speed that can vary
between about 200.degree. C./s to 400.degree. C./s in a quenching
step that is based on the selected gauge. For example, the quench
rate can be from about 225.degree. C./s to about 375.degree. C./s,
from about 250.degree. C./s to about 350.degree. C./s, or from
about 275.degree. C./s to about 325.degree. C./s.
[0171] In the quenching step, the sheet is rapidly quenched with a
liquid (e.g., water) and/or gas or another selected quench medium.
In certain aspects, the sheet can be rapidly quenched with water.
In certain aspects, the sheet is quenched with air.
Aging
[0172] In certain aspects, the sheet can optionally be pre-aged at
about 80.degree. C. to about 120.degree. C. (e.g., about 80.degree.
C., about 85.degree. C., about 90.degree. C., about 95.degree. C.,
about 100.degree. C., about 105.degree. C., about 110.degree. C.,
about 115.degree. C., or about 120.degree. C.) for a period of
time. Optionally, the sheet can be pre-aged for a period from 30
minutes to about 12 hours (e.g., 30 minutes, 1 hour, 2 hours, 3
hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10
hours, 11 hours, or 12 hours), or anywhere in between.
[0173] The sheet can be naturally aged for a period of time to
result in the T4 temper. In certain aspects, the sheet in the T4
temper can be artificially aged at about 180.degree. C. to about
225.degree. C. (e.g., 185.degree. C., 190.degree. C., 195.degree.
C., 200.degree. C., 205.degree. C., 210.degree. C., 215.degree. C.,
220.degree. C., or 225.degree. C.) for a period of time.
Optionally, the sheet can be artificially aged for a period from
about 15 minutes to about 8 hours (e.g., 15 minutes, 30 minutes, 1
hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, or 8
hours or anywhere in between) to result in the T6 temper.
Optionally, the sheet can be artificially aged for a period from
about 10 minutes to about 2 hours (e.g., 15 minutes, 20 minutes, 30
minutes, 45 minutes, 1 hour, 1.5 hours, 2 hours or anywhere in
between) to result in the T8 temper.
Methods of Using
[0174] The alloys and methods described herein can be used in
automotive, electronics, and transportation applications, such as
commercial vehicle, aircraft, or railway applications. For example,
the alloys could be used for chassis, cross-member, and
intra-chassis components (encompassing, but not limited to, all
components between the two C channels in a commercial vehicle
chassis) to gain strength, serving as a full or partial replacement
of high-strength steels. In certain examples, the alloys can be
used in F, T4, T6x, or T8x tempers. In certain aspects, the alloys
are used with a stiffener to provide additional strength. In
certain aspects, the alloys are useful in applications where the
processing and operating temperature is approximately 150.degree.
C. or lower.
[0175] In certain aspects, the alloys and methods can be used to
prepare motor vehicle body part products. For example, the
disclosed alloys and methods can be used to prepare automobile body
parts, such as bumpers, side beams, roof beams, cross beams, pillar
reinforcements (e.g., A-pillars, B-pillars, and C-pillars), inner
panels, side panels, floor panels, tunnels, structure panels,
reinforcement panels, inner hoods, or trunk lid panels. The
disclosed aluminum alloys and methods can also be used in aircraft
or railway vehicle applications, to prepare, for example, external
and internal panels. In certain aspects, the disclosed alloys can
be used for other specialties applications, such as automotive
battery plates/shates.
[0176] In certain aspects, the products created from the alloys and
methods can be coated. For example, the disclosed products can be
Zn-phosphated and electrocoated (E-coated). As part of the coating
procedure, the coated samples can be baked to dry the E-coat at
about 180.degree. C. for about 20 minutes. In certain aspects, a
paint bake response is observed wherein the alloys exhibit an
increase in yield strength. In certain examples, the paint bake
response is affected by the quenching methods during plate, shate
or sheet forming.
[0177] The described alloys and methods can also be used to prepare
housings for electronic devices, including mobile phones and tablet
computers. For example, the alloys can be used to prepare housings
for the outer casing of mobile phones (e.g., smart phones) and
tablet bottom chassis, with or without anodizing. Exemplary
consumer electronic products include mobile phones, audio devices,
video devices, cameras, laptop computers, desktop computers, tablet
computers, televisions, displays, household appliances, video
playback and recording devices, and the like. Exemplary consumer
electronic product parts include outer housings (e.g., facades) and
inner pieces for the consumer electronic products.
[0178] The following examples will serve to further illustrate the
present invention without, however, constituting any limitation
thereof. On the contrary, it is to be clearly understood that
resort may be had to various embodiments, modifications and
equivalents thereof which, after reading the description herein,
may suggest themselves to those skilled in the art without
departing from the spirit of the invention. During the studies
described in the following examples, conventional procedures were
followed, unless otherwise stated. Some of the procedures are
described below for illustrative purposes.
EXAMPLES
Example 1: Properties of Aluminum Alloys TB1, TB2, TB3, and TB4
[0179] A set of four exemplary aluminum alloys were prepared: TB1,
TB2, TB3, and TB4 (Table 16).
TABLE-US-00016 TABLE 16 Compositions of TB1-TB4 Alloys (wt. %)
Alloy Cr Cu Fe Mg Mn Si Zn Sc Zr TB1 0.03-0.06 0.7-0.9 0.15-0.18
1.0-1.25 0.05-0.2 1.00-1.2 0.005 TB2 0.06-0.1 0.6-0.7 0.18-0.25
1.15-1.3 0.15-0.2 0.8-1.1 0.004 0.05-0.15 0.02-0.09 TB3 0.03-0.06
0.6-0.9 0.15-0.20 1.0-1.3 0.05-0.18 0.9-1.3 0.2-0.9 TB4 0.03-0.09
0.65-0.9 0.15-0.25 1.05-1.3 0.1-0.2 0.8-1.2 0.1-0.9 0.05-0.2
0.01-0.08
[0180] The alloys were prepared by DC casting the components into
ingots and homogenizing the ingots at 520.degree. C. to 580.degree.
C. for 1-5 hours. The homogenized ingots were then laid down and
hot rolled with an entry temperature range of 500.degree. C. to
540.degree. C. and a hot roll exit temperature range of from
250.degree. C. to 380.degree. C. A solution heat treatment step was
then performed at 540.degree. C. to 580.degree. C. for 15 minutes
to 2 hours, followed by a room temperature quench using water and
natural aging to achieve the T4 temper. The T6 temper was achieved
by aging the T4 alloys at 180.degree. C. to 225.degree. C. for 15
minutes to 8 hours.
[0181] The properties of the TB1-TB4 alloys were determined using
testing procedures conventional in the art and compared to the
control alloys AA6061, AA6013, and AA6111 (Table 17).
TABLE-US-00017 TABLE 17 Properties of TB1-TB4 Alloys IGC depth YS
in UE in Min in T6 AQ grade Thickness T6 T4 r/t (G110) in WI/YI
Alloy (mm) (MPa) (%) in T4 .mu.m (acidic) AA6061 3-6 250-260 14-18
<2.5 -- 48.9/6.35 TE AA6013 10 323-360 23 1.4 -- -- AA6111 10
323 25 1.3 -- -- TB1 10 380-390 28 <0.5 140-150 50/5 .mu.m
(est.) TB2 10 385-395 25 <0.5 120-130 50/5 .mu.m (est.) TB3 10
380-390 28 <0.8 120-130 50/5 .mu.m (est.) TB4 10 380-390 25
<0.5 140-150 50/5 .mu.m (est.)
[0182] In comparison with current commercial high strength 6XXX
alloys, for example AA6061, AA6111 and AA6013, these examples of
the inventive alloy demonstrate significant improvements in uniform
elongation (UE) and bendability in T4 (FIGS. 1 and 2) and yield
strength (YS) and corrosion resistance in T6 (FIG. 3) (Table 17).
The TB1-TB4 alloys reached about 25-28% UE.
Example 2: Effects of Annealing
[0183] This example compares the properties of an annealed TB1
alloy in T4 condition over a control TB1 alloy produced by a
similar process without an annealing step.
[0184] The composition of the TB1 alloy is as discussed above in
Table 16. Similar to Example 1, initial processing for both samples
included regular DC casting; homogenization with a heat-up rate of
10-100.degree./C and soaking at a peak metal temperature of
520-580.degree. C. for 1-5 hours; and hot rolling with an entry
temperature range of 500-540.degree. C. and a hot roll exit
temperature range of 250-380.degree. C. The as-rolled plate/shates
were marked as being in F temper. For the control alloy, the F
temper plate/shates were then converted to T4 temper by
solutionization at 540-580.degree. C. for 15 min to 2 hours soaking
time, followed by a water quench and natural aging. The control was
converted directly from F temper to T4 temper without an
intervening annealing step.
[0185] For the annealed alloy, the F temper plates/shates were
annealed at a temperature range of 400-500.degree. C. and a soaking
time of 30-120 min. The resulting as-annealed, O temper
plates/shates were then converted to T4 temper by solutionization
at 540-580.degree. C. for 15 min to 2 hours soaking time, followed
by a water quench and natural aging.
[0186] FIG. 4 illustrates the orientation distribution function
(ODF) graphs for the resulting control and annealed alloys. The ODF
graphs are in sections at .phi.2=0.degree., 45.degree., and
65.degree., respectively. Examination indicates that the
intensities of high r-45.degree. TCs (such as Brass, Cu) and high
r-0/180.degree. TCs (such as Goss, Goss-ND, Cube-RD) are reduced in
the annealed alloy compared to the control, indicating an improved
texture. This improved texture can potentially reduce the
bendability anisotropy and can improve the formability in the
forming where a drawing or circumferential stamping process is
involved, as it acts to reduce the variability in properties at
different directions (i.e., anisotropy).
[0187] The alloy samples were further aged at 180.degree. C.
225.degree. C. for 15 min to 8 hours. Investigation of the tensile
properties of the alloys indicated that annealing had not adversely
affected the final T6 strength (FIG. 5).
Example 3: Properties of Aluminum Alloys P7, P8, and P14 with
Different SHTs
[0188] A set of three exemplary aluminum alloys were prepared: P7,
P8, and P14 (Table 18).
TABLE-US-00018 TABLE 18 Compositions of P7, P8, and P14 Alloys (wt.
%) Alloy Cr Cu Fe Mg Mn Si Zn Ti P7 0.03 0.66 0.16 1.16 0.17 1.19
0.005 0.02 P8 0.03 0.80 0.18 1.11 0.19 0.97 0.005 0.02 P14 0.03
0.61 0.18 1.20 0.18 1.09 0.004 0.02
[0189] The alloys were prepared according to the procedure of
Example 1, with the exception that the solution heat treatment
soaking step was performed for a shorter period (either 45 or 120
seconds).
[0190] The maximum elongation (in T4 condition) and yield strengths
(in T6 condition) of the P7, P8, and P14 alloys were determined
using testing procedures conventional in the art (FIG. 6).
Follow-up experiments were performed using different SHT
conditions, including temperatures ranging from 550.degree. C. to
580.degree. C. (FIGS. 7 and 8).
[0191] In comparison with current commercial high strength 6xxx
alloys, such as AA6061, AA6111 and AA6013 (see Example 1), the P7,
P8, and P14 alloys demonstrate significant improvements in yield
strength and corrosion resistance in T6 and uniform elongation.
Such improvement is resulted by a combination of well-designed
chemical composition and thermomechanical processing.
Example 4: Properties of SL Series Aluminum Alloys
[0192] An additional set of aluminum alloys were prepared (Table
19).
TABLE-US-00019 TABLE 19 Compositions of SL Series Alloys (wt. %)
Alloy Cr Cu Fe Mg Mn Si Zn Ti Ni SL1 0.033 0.79 0.22 0.82 0.28 0.83
0.0096 0.0234 0.0052 SL2 0.072 0.81 0.22 1.09 0.11 1.24 0.01 0.024
0.0055 SL3 0.11 1.70 0.19 0.98 0.02 0.69 0.0214 0.021 0.0042 SL4
0.01 0.74 0.28 0.71 0.11 0.65 0.010 0.029 0.006 SL5 0.027 0.84 0.22
0.91 0.293 0.65 0.07 0.022 0.0036 SL6 0.028 0.79 0.21 0.74 0.14
1.20 0.01 0.026 0.0048 SL7 0.026 0.68 0.20 1.17 0.14 0.82 0.007
0.024 0.0047 SL8 0.012 0.97 0.23 1.04 0.31 1.00 0.005 0.029
0.008
[0193] The alloys were prepared according to the procedure of
Example 1. The properties of four of the alloys--SL1, SL2, SL3, and
SL4--were tested extensively by standard procedures according to EN
10002-1 to establish their yield strength (FIG. 9), tensile
strength (FIG. 10), and elongation properties (FIGS. 11 and 12).
The bendability was tested according to VDA 238-100 (FIG. 13). The
quasi-static crush test was performed with a 300 mm long crush tube
(U-shape) and a crush velocity of 10 mm/s and a total displacement
of 185 mm (FIG. 15). The lateral crash test was performed with an
80 mm punch diameter, a velocity of 10 mm/s and displacement of 100
mm. The bending tube was built with an outer angle of 70.degree.
between back plate and lateral plate (FIG. 18). Comparative results
were collected for samples that were prepared at low PMTs (e.g.,
from 520-535.degree. C.) and high PMTs (e.g., from about
536.degree. C. 560.degree. C.). Samples tested were 2 mm thick or
2.5 mm for SL1. For the bending results, the outer bend angle was
used. The alloy demonstrated a bend angle of less than 90.degree.
in T4 temper and less than 135.degree. in T6 temper.
[0194] To normalize the angle at 2.0 mm, the following formula was
used:
.alpha. norm = .alpha. measure .times. t measure t norm
##EQU00001##
where .alpha..sub.measure is the outer bend angle, alpha,
t.sub.measure is the thickness of the sample, t.sub.norm is the
normalized thickness, and .alpha..sub.norm is the resulting
normalized angle (FIG. 39). A comparison of yield strength with
bendability showed that SL4 performed the best amongst the tested
alloys (FIG. 14).
[0195] Quasi-static crush tests demonstrated good crushability for
alloy SL3 in a T6 temper condition (aged at 180.degree. C. for 10
h) with a Rp02 of 330 MPa and very high Rm of 403 MPa. T6 temper
was chosen to test the worst case scenario for parts in a body in
white stage or a motor carrier operating in an elevated temperature
environment. Providing an adequate outer bending angle (alpha about
68.degree.) and a high UTS of more than 400 MPa, Alloy SL3 is
suitable for automotive structural applications including a
B-pillar, an A-pillar, a C-pillar or a floor panel. The high UTS
(Rm>400 MPa) is due to the Cu level of 1.7 wt. %. Typically, at
least 1.5 wt. % is necessary for good crushability. FIG. 15 is a
graph showing the crush test results of Alloy SL3 in T6 temper
presenting energy and load as a function of displacement. FIGS.
16A-16F are digital images and accompanying line drawings of crush
samples of Alloy SL3 sample 2 after the crush test. Line drawings
are presented for clarity. FIGS. 17A-17F are digital images and
accompanying line drawings of crush samples of Alloy SL3 sample 3
after the crush test.
[0196] Lateral crash tests demonstrated very good bendability for
alloy SL3 in a T6 temper condition (aged at 180.degree. C. for 10
hours) with a Rp02 of 330 MPa and very high Rm of 403 MPa. As
demonstrated by the quasi-static crush test and substantiated by
the lateral crash test, Alloy SL3 is suitable for automotive
structural applications. FIG. 18 is a graph showing the crash test
results of Alloy SL3 in T6 temper presenting energy and load as a
function of displacement. FIGS. 19A-19D are digital images and
accompanying line drawings of crash samples of Alloy SL3 sample 1
after the crash test. FIGS. 20A-20D are digital images and
accompanying line drawings of crash samples of Alloy SL3 sample 2
after the crash test.
Example 5: Effects of Different Quenches on Properties of SL2
[0197] The effects of different quenching conditions on yield
strength and bendability were tested for alloy composition SL2
prepared at 550.degree. C. PMT (FIG. 21). An air quench, water
quench at 50.degree. C./s, and water quench at 150.degree. C./s
were all tested using standard quenching conditions as per Example
4. The results suggested no major effect on yield strength, but
improvements in bendability from the water quenches.
Example 6: Effect on Hardness
[0198] An additional set of aluminum alloys was prepared (Table
20).
TABLE-US-00020 TABLE 20 Compositions of Alloys (wt. %) Alloy Cr Cu
Fe Mg Mn Si S164 0.03 0.50 0.21 1.26 0.14 1.07 S165 0.03 0.51 0.23
0.91 0.15 1.21 S166 0.03 0.67 0.22 1.21 0.17 0.74 S167 0.03 0.70
0.20 1.0 0.14 1.11 S168 0.09 0.72 0.24 1.26 0.10 0.75 S169 0.09
0.71 0.22 1.0 0.11 1.12
[0199] The alloys were prepared according to Example 1, except that
the casting was performed using book molds. The yield strengths of
the alloys S164, S165, S166, S167, S168, and S169 after different
heat treatments were tested using standard conditions as in Example
4 (FIG. 22). Higher aging temperatures (e.g., 225.degree. C.) led
to an overaged condition.
[0200] The hardness of the different alloys were also tested at
their fully aged T6 conditions at after three heat treatments
(SHT1, SHT2, and SHT3 of FIGS. 6-8). The time and temperature
during solutionizing heat treatment impacted the hardness of the
alloy (FIG. 23).
Example 7: Effect of Zn
[0201] An additional set of aluminum alloys was prepared (Table
21).
TABLE-US-00021 TABLE 21 Compositions of Alloys (wt. %) Alloy Si Fe
Cu Mn Mg Zn Ti S281 0.73 0.22 0.82 0.32 0.94 0.00 0.13 S282 0.76
0.20 0.84 0.32 0.94 0.52 0.14 S283 0.76 0.22 0.91 0.32 0.94 3.09
0.12
[0202] The alloys were prepared by DC casting the components into
ingots and the casting was performed using book molds. The ingots
were homogenized at 520.degree. C. to 580.degree. C. for 1-15
hours. The homogenized ingots were then laid down and hot rolled
with an entry temperature range of 500.degree. C. to 540.degree. C.
and a hot roll exit temperature range of from 250.degree. C. to
380.degree. C. A solution heat treatment step was then performed at
540.degree. C. to 580.degree. C. for 15 minutes to 2 hours,
followed by a room temperature quench using water and natural aging
to achieve the T4 temper. The T6 temper was achieved by aging the
T4 alloys at 180.degree. C. to 225.degree. C. for 15 minutes to 12
hours. The T8 temper was achieved by aging the T6 alloys at
180.degree. C. to 215.degree. C. for 10 minutes to 2 hours.
[0203] Tensile strength of the exemplary alloys is shown in FIG.
24. Zn additions increased the strength of alloys in T4 temper, but
more importantly increased the strength of alloys in T6 temper and
T8 temper. The graph shows it is possible to achieve tensile
strengths greater than 370 MPa without prestraining alloys in T6
temper. The graph shows it is possible to achieve tensile strengths
greater than 340 MPa for alloys including up to about 3 wt. % Zn in
T8 temper. PX indicates pre-aging or re-heating after solutionizing
and quenching. The pre-aging is performed at a temperature between
90.degree. C. 110.degree. C. for a period of time between 1-2
hours.
[0204] Bending results of the exemplary alloys are shown in FIG.
25. Addition of Zn presents no clear trend in the bending data. The
data do indicate a slight decrease in formability. FIG. 26 compares
the increased strength to the formability of exemplary alloys. The
Zn addition provides a negligible degradation of formability in the
exemplary alloys.
[0205] Paint bake results of the exemplary alloys are shown in FIG.
27. The data shows a paint bake response is not affected by Zn
addition, particularly after pre-heating.
[0206] Elongation of the exemplary alloys is shown in FIG. 28. The
graph demonstrates the elongation of the exemplary alloys is not
degraded after Zn addition. Strength increase due to the Zn
addition provides a greater formability in a high-strength aluminum
alloy. Adding up to 3 wt. % Zn increases strength in exemplary
alloys without significantly decreasing formability or
elongation.
Example 8: Properties of Exemplary Aluminum Alloys TB7, TB8, PF5,
TB13, TB14, PF4, TB15, TB16, PF11, PF12, and Comparative Aluminum
Alloys PF13 and TB5
[0207] A set of ten exemplary alloys was prepared: TB7, TB8, PF5,
TB13, TB14, PF4, TB15, TB16, PF11, PF12 and TB5 (Table 22):
TABLE-US-00022 TABLE 22 Compositions of TB5-TB16 and PF5-PF13
Alloys (wt. %) Alloy Cr Cu Fe Mg Mn Si Zr Zn Ti Excess Si TB7 0.06
0.65 0.20 1.47 0.09 1.04 0 0.04 0.01 -0.49 TB8 0.09 0.67 0.21 1.45
0.10 1.03 0 0.01 0.01 -0.49 PF5 0.06 1.28 0.14 0.82 0.20 0.97 0.10
0.006 0.013 0.08 TB13 0.07 1.25 0.22 1.12 0.04 1.05 0 0.01 0.02
-0.13 TB14 0.06 1.27 0.13 0.96 0.18 0.78 0.09 0.005 0.014 -0.24 PF4
0.14 1.75 0.16 0.74 0.00 0.86 0.09 0.005 0.012 0.07 TB15 0.16 1.80
0.18 1.16 0.01 1.02 0.09 0.012 0.024 -0.20 TB16 0.16 1.82 0.18 1.16
0.00 1.04 0.10 0.005 0.136 -0.18 PF11 0.02 0.65 0.19 1.01 0.17 0.94
0.1 0.21 0.02 -0.13 PF12 0.03 0.75 0.18 0.95 0.28 0.75 0.1 0.2 0.03
-0.28 PF13 0.03 0.74 0.19 0.93 0.27 0.73 0 0.2 0.03 -0.28 TB5 0.28
0.62 0.2 0.86 0.09 0.64 0 0.67 0.02 -0.32
[0208] The alloys were prepared by DC casting the components into
ingots and homogenizing the ingots at 520.degree. C. to 580.degree.
C. for 1-5 hours. The homogenized ingots were then laid down and
hot rolled with an entry temperature range of 500.degree. C. to
540.degree. C. and a hot roll exit temperature range of from
250.degree. C. to 380.degree. C. A solution heat treatment step was
then performed at 540.degree. C. to 580.degree. C. for 15 minutes
to 2 hours, followed by a room temperature quench using water and
natural aging to achieve the T4 temper. The T6 temper was achieved
by aging the T4 alloys at 150.degree. C. to 250.degree. C. for 15
minutes to 24 hours.
[0209] The properties of the TB7, TB8, PF5, TB13, TB14, PF4, TB15,
TB16, PF11 and PF12 alloys were determined using testing procedures
conventional in the art and compared to the control alloys PF13 and
TB5 (Table 23). Corrosion tests were performed according to the ISO
11846 standard.
TABLE-US-00023 TABLE 23 Properties of TB7, TB8, PF5, TB13, TB14,
PF4, TB15, TB16, PF11, PF12, PF13 and TB5 Alloys Gauge 10 mm 10 mm
2 mm 2 mm 2 mm 2 mm Temper T6 T6 T4 T6 T6 T6 Property YS IGC depth
Bend Angle YS Bend Angle IGC depth Alloy (MPa) (.mu.m) .beta.
(.degree.) (MPa) .beta. (.degree.) (.mu.m) TB7 391 211 77 374 133
433 TB8 394 130 75 376 129 343 PF5 376 221 61.8 377 122 181 TB13
390 253 68 376 131 335 TB14 386 245 61.7 379 117 84 PF4 376 239 81
359 132 79 TB15 390 288 82.7 371 131 210 TB16 387 250 88.7 377 131
39 PF11 388 372 42 378 118 289 PF12 358 285 38.8 353 94 245 PF13
356 350 33.3 343 98 364 TB5 321 -- -- -- -- --
[0210] Overall, the exemplary alloys demonstrated improved yield
strength and corrosion resistance when compared to the comparative
PF13 and TB5 alloys.
Example 9: Properties of Exemplary Aluminum Alloys PF1, PF2 and
PF6
[0211] A set of three exemplary alloys was prepared: PF1, PF2 and
PF6 (Table 24).
TABLE-US-00024 TABLE 24 Compositions of PF1, PF2 and PF6 Alloys
(wt. %) Alloy Cr Cu Fe Mg Mn Si Zr Ti PF1 0.08 0.69 0.17 1.15 0.08
1.26 0 0.02 PF2 0.08 0.67 0.14 1.17 0.09 1.27 0.09 0.03 PF6 0.07
0.67 0.14 1.15 0.19 1.27 0.09 0.02
[0212] The alloys were prepared by DC casting the components into
ingots and homogenizing the ingots at 520.degree. C. to 580.degree.
C. for 1-5 hours. The homogenized ingots were then laid down and
hot rolled with an entry temperature range of 500.degree. C. to
540.degree. C. and a hot roll exit temperature range of from
250.degree. C. to 380.degree. C. A solution heat treatment step was
then performed at 540.degree. C. to 580.degree. C. for 15 minutes
to 2 hours, followed by a room temperature quench using water and
natural aging to achieve the T4 temper. The T6 temper was achieved
by aging the T4 alloys at 150.degree. C. to 250.degree. C. for 15
minutes to 24 hours. The properties of the PF1, PF2, and PF6 alloys
were determined using testing procedures conventional in the art.
Corrosion tests were performed according to the ISO 11846
standard.
[0213] FIG. 29 is a chart that shows the tensile strengths of
exemplary alloys PF1, PF2 and PF6 ("-LET" refers to low exit
temperature). The alloys comprise various amounts of Zr in the
composition. The alloys were rolled to 2 mm and 10 mm gauge. The
alloys were subjected to aging methods resulting in T6 temper
condition. The alloys demonstrate high tensile strengths for both
gauges in T6 temper.
[0214] FIG. 30 is a chart that shows formability of exemplary
alloys PF1, PF2 and PF6. The alloys comprise various amounts of Zr
in the composition. The alloys were rolled to 2 mm gauge. The
alloys were subjected to aging methods resulting in T4 temper
condition. The alloys exhibit a bending angle less than 90.degree.
for a 2 mm gauge in T4 temper. FIG. 31 is a chart that shows
formability of exemplary alloys PF1, PF2 and PF6 rolled to 2 mm
gauge and subjected to aging methods resulting in T6 temper
condition. The alloys containing Zr (PF2 and PF6) exhibit a bend
angle less than 135.degree. for a 2 mm gauge alloy in T6
temper.
[0215] FIG. 32 is a chart that shows maximum corrosion depth of
exemplary alloys PF1, PF2 and PF6. The alloys comprise various
amounts of Zr in the composition. The alloys were rolled to 2 mm
gauge. The alloys containing Zr demonstrated increased resistance
to corrosion indicated by a lower maximum corrosion depth. FIGS.
33-38 show micrographs of cross-sectional views of exemplary alloys
PF1, PF2 and PF6 after corrosion testing. The alloys comprise
various amounts of Zr in the composition. The alloys were rolled to
2 mm gauge. Alloy PF1 exhibited a higher depth of corrosion
compared to alloys PF2 and PF6. FIGS. 33 and 34 show the corrosion
in alloy PF1. FIGS. 35 and 36 show the corrosion in alloy PF2.
FIGS. 37 and 38 show the corrosion in alloy PF6. The alloys
containing Zr (PF2 and PF6) demonstrated a higher resistance to
corrosion.
[0216] 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.
* * * * *