U.S. patent application number 13/524167 was filed with the patent office on 2013-05-30 for aluminum alloy and method for producing the same.
This patent application is currently assigned to KIA MOTORS CORPORATION. The applicant listed for this patent is Hoo Dam LEE, Hoon Mo PARK. Invention is credited to Hoo Dam LEE, Hoon Mo PARK.
Application Number | 20130136651 13/524167 |
Document ID | / |
Family ID | 48288054 |
Filed Date | 2013-05-30 |
United States Patent
Application |
20130136651 |
Kind Code |
A1 |
PARK; Hoon Mo ; et
al. |
May 30, 2013 |
ALUMINUM ALLOY AND METHOD FOR PRODUCING THE SAME
Abstract
The present disclosure provides an aluminum (Al) alloy, for
general casting, and a technique for producing the same. The Al
alloy includes Al, Si in the range of 5 to 13 wt %, Ti in the range
of 2 to 7 wt % and B in the range of 1 to 3 wt %. According to the
disclosure, a TiB.sub.2 compound may be formed in the Al alloy,
where the ratio of Ti:B may range from 2 to 2.5 wt %. The Al alloy
of the disclosure has improved elasticity, and is suitable for
general casting processes such as, for example, high pressure
casting process.
Inventors: |
PARK; Hoon Mo; (Seongnam,
KR) ; LEE; Hoo Dam; (Hwaseong, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PARK; Hoon Mo
LEE; Hoo Dam |
Seongnam
Hwaseong |
|
KR
KR |
|
|
Assignee: |
KIA MOTORS CORPORATION
Seoul
KR
HYUNDAI MOTOR COMPANY
Seoul
KR
|
Family ID: |
48288054 |
Appl. No.: |
13/524167 |
Filed: |
June 15, 2012 |
Current U.S.
Class: |
420/532 ;
420/531; 420/535; 420/537; 420/548; 75/678 |
Current CPC
Class: |
C22C 21/04 20130101;
C22F 1/053 20130101 |
Class at
Publication: |
420/532 ;
420/548; 420/531; 420/535; 420/537; 75/678 |
International
Class: |
C22C 21/02 20060101
C22C021/02; C22C 1/02 20060101 C22C001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 28, 2011 |
KR |
10-2011-0125048 |
Claims
1. An aluminum alloy, comprising: Al, Si in the range of 5 to 13 wt
%, Ti in the range of 2 to 7 wt %, and B in the range of 1 to 3 wt
%.
2. The aluminum alloy of claim 1, wherein a TiB.sub.2 compound is
formed therein.
3. The aluminum alloy of claim 1, further comprising: Fe in the
range of 1.0 to 1.5 wt %, Cu in the range of 1.5 to 3.5 wt %, Mn in
the range of 0.5 wt % or less, Mg in the range of 0.3 wt % or less,
Ni in the range of 0.5 wt % or less, and Zn in the range of 1 wt %
or less.
4. The aluminum alloy of claim 3, wherein the amount of Mg, Ni, and
Zn is more than 0 wt %.
5. The aluminum alloy of claim 1, further comprising Fe in the
range of 0.2 wt % or less, Cu in the range of 0.2 wt % or less, Mn
in the range of 0.1 wt % or less, Mg in the range of 0.25 to 0.45
wt %, Ni in the range of 0.05 wt % or less, and Zn in the range of
0.1 wt % or less.
6. The aluminum alloy of claim 5, wherein the amount of Fe, Cu, Mn,
Mg, Ni, and Zn is more than 0 wt %.
7. The aluminum alloy of claim 1, wherein the ratio of B:Ti is
1:2.about.2.5.
8. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.
9. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.1.
10. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.2.
11. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.3.
12. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.4.
13. The aluminum alloy of claim 7, wherein the ratio of B:Ti is
1:2.5.
14. A method for producing the aluminum alloy of claim 1,
comprising: mixing a molten Al--Ti-based alloy comprising Ti in the
range of 5 to 10 wt % and a molten Al--B-based alloy comprising B
in the range of 2 to 10 wt % together, thereby forming the aluminum
alloy.
15. The method of claim 14, wherein a TiB.sub.2 compound is formed
in the aluminum alloy.
16. The method of claim 14, wherein the ratio of B:Ti is 1:2.
17. The method of claim 14, wherein the ratio of B:Ti is 1:2.1.
18. The method of claim 14, wherein the ratio of B:Ti is 1:2.2.
19. The method of claim 14, wherein the ratio of B:Ti is 1:2.3.
20. The method of claim 14, wherein the ratio of B:Ti is 1:2.4.
21. The method of claim 14, wherein the ratio of B:Ti is 1:2.5.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims under 35 U.S.C. .sctn.119(a) the
benefit of Korean Patent Application No. 10-2011-0125048 filed on
Nov. 28, 2011, the entire contents of which are incorporated herein
by reference.
BACKGROUND
[0002] (a) Technical Field
[0003] The present disclosure relates to an aluminum alloy as a
casting aluminum material with high elasticity for improving the
rigidity and noise, vibration, and harshness (NVH) characteristics,
and a method for producing the same.
[0004] (b) Background Art
[0005] Aluminum alloys improve the properties of aluminum and
displays many excellent properties, which can be varied according
to the composition of the alloy. For example, high strength
aluminum alloys, such as duralumin, can be made by including
copper, which provides high strength characteristics to the alloy.
Increasing the copper content in the alloy has the effect of
increasing the strength of the alloy. For example, super duralumin
is created by adding copper to the duralumin, and extra super
duralumin is created by adding copper to super duralumin. Extra
super duralumin is used as an aircraft material. Disadvantageously,
such high strength aluminum-copper (Al--Cu_alloys such as duralumin
lack the ability to resist corrosion (i.e. they are prone to
corrosion). Structural aluminum alloys are typically made by adding
magnesium and zinc, which confer excellent corrosion resistance
properties to the alloys. Accordingly, such structural aluminum
alloys are used for railway vehicles, bridges, and the like.
Aluminum alloy for casting can be made by adding Si, and other
metals can be mixed with Al to create alloys with a variety of
other properties, such as heat-resistance and brilliance.
[0006] Aluminum alloys are largely divided into two groups: alloys
for wrought material and alloys for casting material. The former
group includes Al--Cu--Mg-based alloys (e.g., duralumin, super
duralumin), Al--Mn-based alloys, Al--Mg--Si-based alloys,
Al--Mg-based alloys, and Al--Zn--Mg-based alloys (extra super
duralumin) alloys. The latter group includes Al--Cu-based alloys,
Al--Si-based alloys (silumin), Al--Cu--Si-based alloys (lautal),
Al--Mg-based alloys (hydronalium), Al--Cu--Mg--Si-based alloys (Y
alloy), and Al--Si--Cu--Mg--Ni-based alloys (Lo.Ex alloy).
[0007] Recently, attempts have been made to generate a metal-based
compound reinforced with carbon nanotubes (CNT) molded in a powder
form, however, use of such a compound is limited because of its
high cost. Disadvantageously, when it was applied to a casting
process in a powder form, major problems were encountered with
dispersion of the powder in an Al matrix. A further disadvantage
results from a hypereutectic aluminum casing material that can only
be made by a low pressure casting process. A further disadvantage
is that processing such a material with coarse Si particles poses
additional manufacturing difficulties. For example, when Si is used
to increase the elasticity of a metal-based compound, or a
reinforced CNT material molded in a powder form, the coarse Si
particles limited the ability to improve elasticity, due in part to
problems with the wetability when combined with the Al matrix,
which resulted in uneven dispersion of the CNT powder when used for
a continuous casting process. Additionally, the ability to work
with such materials is cost prohibitive.
[0008] Accordingly, there is a need in the art for an aluminum
alloy with high elasticity for use as a casting aluminum material
to with improved the rigidity and noise, vibration, and harshness
(NVH) characteristics.
SUMMARY OF THE DISCLOSURE
[0009] The present invention provides a continuous casting aluminum
alloy for use as a high elastic continuous casting aluminum
material with improved rigidity and noise, vibration, and harshness
(NVH) characteristics, and a method for producing the same.
[0010] An aluminum alloy according to an exemplary embodiment of
the present invention includes Al as a major component, Si in the
range of 5 to 13 wt %, Ti in the range of 2 to 7 wt % and B in the
range of 1 to 3 wt %, and a TiB.sub.2 compound can be formed
therein.
[0011] According to an exemplary embodiment of the present
invention the aluminum alloy can include Al as a major component,
Si in the range of 5 to 13 wt %, Ti in the range of 2 to 7 wt %, B
in the range of 1 to 3 wt %, Fe in the range of 1.0 to 1.5 wt %, Cu
in the range of 1.5 to 3.5 wt %, Mn in the range of 0.5 wt % or
less (not including 0), Mg in the range of 0.3 wt % or less (not
including 0), Ni in the range of 0.5 wt % or less (not including
0), Zn in the range of 1 wt % or less (not including 0) and other
indispensable impurities.
[0012] According to an exemplary embodiment of the present
invention the aluminum alloy can include Al as a major component,
Si in the range of 5 to 13 wt %, Ti in the range of 2 to 7 wt %, B
in the range of 1 to 3 wt %, Fe in the range of 0.2 wt % or less
(not including 0), Cu in the range of 0.2 wt % or less (not
including 0), Mn in the range of 0.1 wt % or less (not including
0), Mg in the range of 0.25 to 0.45 wt %, Ni in the range of 0.05
wt % or less (not including 0), Zn in the range of 0.1 wt % or less
(not including 0) and other indispensable impurities.
[0013] The ratio of B:Ti may be 1:2.about.2.5.
[0014] According to an exemplary embodiment of the present
invention a method for producing the aluminum alloy includes,
preparing a molten Al--Ti-based alloy comprising Ti in the range of
5 to 10 wt % and a molten Al--B-based alloy comprising B in the
range of 2 to 10 wt %, and mixing the molten alloys together.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above and other features of the present invention will
now be described in detail with reference to certain exemplary
embodiments thereof illustrated the accompanying drawings which are
given hereinbelow by way of illustration only, and thus are not
limitative of the present invention, and wherein:
[0016] FIG. 1 is a graph comparing the TiB.sub.2 fractions of
aluminum alloys according to an exemplary embodiment of the present
invention.
[0017] It should be understood that the appended drawings are not
necessarily to scale, presenting a somewhat simplified
representation of various preferred features illustrative of the
basic principles of the invention. In the figures, reference
numbers refer to the same or equivalent parts of the present
invention throughout the several figures of the drawing.
DETAILED DESCRIPTION
[0018] Hereinafter reference will now be made in detail to various
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings and described below. While
the invention will be described in conjunction with exemplary
embodiments, it will be understood that the present description is
not intended to limit the invention to those exemplary embodiments.
On the contrary, the invention is intended to cover not only the
exemplary embodiments, but also various alternatives,
modifications, equivalents and other embodiments, which may be
included within the spirit and scope of the invention as defined by
the appended claims.
[0019] Unless specifically stated or obvious from context, as used
herein, the term "about" is understood as within a range of normal
tolerance in the art, for example within 2 standard deviations of
the mean. "About" can be understood as within 10%, 9%, 8%, 7%, 6%,
5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated
value. Unless otherwise clear from the context, all numerical
values provided herein are modified by the term "about."
[0020] Ranges provided herein are understood to be shorthand for
all of the values within the range. For example, a range of 1 to 50
is understood to include any number, combination of numbers, or
sub-range from the group consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26,
27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
44, 45, 46, 47, 48, 49, or 50, as well as all intervening decimal
values between the aforementioned integers such as, for example,
1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, and 1.9. With respect to
sub-ranges, "nested sub-ranges" that extend from either end point
of the range are specifically contemplated. For example, a nested
sub-range of an exemplary range of 1 to 50 may comprise 1 to 10, 1
to 20, 1 to 30, and 1 to 40 in one direction, or 50 to 40, 50 to
30, 50 to 20, and 50 to 10 in the other direction.
[0021] It is understood that the term "vehicle" or "vehicular" or
other similar term as used herein is inclusive of motor vehicles in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats and ships, aircraft, and
the like, and includes hybrid vehicles, electric vehicles, plug-in
hybrid electric vehicles, hydrogen-powered vehicles and other
alternative fuel vehicles (e.g., fuels derived from resources other
than petroleum). As referred to herein, a hybrid vehicle is a
vehicle that has two or more sources of power, for example both
gasoline-powered and electric-powered vehicles.
[0022] Hereinafter, an aluminum alloy and a method for producing
the same according to the preferred embodiments of the present
invention will now be described in detail with reference to the
accompanying drawings.
[0023] The aluminum alloy according to the present invention has a
composition comprising: Al as a major component, Si in the range of
5.about.13 wt %, Ti in the range of 2.about.7 wt % and B in the
range of 1.about.3 wt % so as to form a TiB.sub.2 compound.
[0024] The present invention provides a high elastic casting
aluminum material with improved rigidity and NVH characteristic.
Conventionally, when only using Si for high elasticity, there were
problems with restricted elasticity improvement and processability
as a result of the coarse Si particles. A metal-based compound or a
reinforced phase such as CNT was molded with a powder form, but it
had a very limited usefulness as a result of the fact that the
material was prohibitively expensive, and because of problems with
the wetability of an Al matrix and the resulting dispersion
problems that arose when the material was applied to a continuous
casting process as the powder form.
[0025] The present invention implements a boride compound to
provide an aluminum alloy having high elasticity, which can
maximize improvement of the uniformity and elasticity of the alloy.
In particular, an exemplary embodiment of the invention enables the
use of a general casting process such as, for example, a high
pressure casting process, to be used.
[0026] The aluminum alloy of the present invention makes up a basic
alloy system by limiting the Si content to the range of 5 to 13 wt
% for embodying the improvements of both castability and
elasticity, and the Ti content to the range of 2 to 7 wt % and the
B content to the range of 1 to 3 wt % for forming the boride
compound (TiB.sub.2: 541 GPa), which is the most effective compound
to improve the elasticity.
[0027] According to another exemplary embodiment of the invention,
in addition to the aluminum alloy, an alloy structure prepared by
adding Ti in the range of 2 to 7 wt % and B in the range of 1 to 3
wt % to the conventional ADCl2, AC4CH, AC2B, which are the most
representative alloy systems for high pressure casting and
gravity/low pressure casting, can also obtain a similar result with
improved elasticity.
[0028] According to an exemplary embodiment of the invention, in
order to maximize boride production in the material, the ratio of
Ti and B is controlled to the range of 2.about.2.5. In order to
control the ratio of Ti and B, a powder-type is not injected;
rather, the ration is formed naturally in a molten metal by using
master aluminum alloys of Al-(in the range of 5 to 10 wt %) Ti and
Al-(in the range of 2 to 10 wt %) B, so as to secure the material
uniformity.
[0029] Through this aluminum alloy, the elasticity and other
properties (such as, e.g., strength, wear-resistance,
processability and the like) are improved by uniform distribution
of the micro-TiB.sub.2 phase and by maximization of boride
production.
[0030] Conventionally, the general elasticity coefficient of an
aluminum alloy is 75 GPa. In contrast, the elasticity coefficient
of the 1Ti-1B (micro-TiB.sub.2 1.45%) aluminum alloy of an
exemplary embodiment of the present invention is significantly
increased to 92.8 GPa. Further, in case of 2.3Ti-1B
(micro-TiB.sub.2 3.34%), the elasticity coefficient is increased to
103.8 GPa.
[0031] Additionally, a hypereutectic aluminum, which is a
representative alloy used in the conventional art as a mass
production material, is restricted to low pressure casting methods.
However, the aluminum alloy of an exemplary embodiment of the
present invention has no such restriction on the casting
process.
[0032] In an exemplary embodiment, the aluminum alloy of the
present invention may have a composition comprising: Al as a major
component, Si in the range of 5 to 13 wt %, Ti in the range of 2 to
7 wt %, B in the range of 1 to 3 wt %, Fe in the range of 1.0 to
1.5 wt %, Cu in the range of 1.5 to 3.5 wt %, Mn in the range of
0.5 wt % or less (not including 0), Mg in the range of 0.3 wt % or
less (not including 0), Ni in the range of 0.5 wt % or less (not
including 0), Zn in the range of 1 wt % or less (not including 0)
and other indispensable impurities.
[0033] Further, as another exemplary embodiment, the aluminum alloy
may have a composition comprising: Al as a major component, Si in
the range of 5 to 13 wt %, Ti in the range of 2 to 7 wt %, B in the
range of 1 to 3 wt %, Fe in the range of 0.2 wt % or less (not
including 0), Cu in the range of 0.2 wt % or less (not including
0), Mn in the range of 0.1 wt % or less (not including 0), Mg in
the range of 0.25 to 0.45 wt %, Ni in the range of 0.05 wt % or
less (not including 0), Zn in the range of 0.1 wt % or less (not
including 0) and other indispensable impurities.
[0034] Table 1 is a table comparing chemical compositions of the
conventional aluminum alloy of the Comparative Example and the
aluminum alloy according to one exemplary embodiment of the present
invention.
TABLE-US-00001 TABLE 1 Si Fe Cu Mn Mg Ni Zn Ti B Al Compar- 9.6~12
1.3 1.5~3.5 0.5 0.3 0.5 1 <0-3 -- Bal. ative Example Present
5~13% -- -- -- -- -- -- 2~7 1~3 Bal. Inven- tion Example 9.6~12 1.3
1.5~3.5 0.5 0.3 0.5 1 2~7 1~3 Bal.
[0035] As shown in Table 1, the aluminum alloy of the present
invention has a composition comprising: Al as a major component, Si
in the range of 5 to 13 wt %, Ti in the range of 2 to 7 wt % and B
in the range of 1 to 3 wt %, so as to form a TiB.sub.2 compound
therein, and as a result, the general elasticity coefficient of an
aluminum alloy is 75 GPa, while the elasticity coefficient of the
1Ti-1B (micro-TiB.sub.2 1.45%) aluminum alloy of the present
invention significantly increased to 92.8 GPa.
[0036] On the other hand, the ratio of B:Ti may be 1:2 to 2.5
because the TiB.sub.2 production increases as the Ti/B ratio is
increased.
[0037] On the other hand, in the method for producing the aluminum
alloy, the aluminum alloy can be prepared by mixing a molten
Al--Ti-based alloy comprising Ti in the range of 5 to 10 wt % and a
molten Al--B-based alloy comprising B in the range of 2 to 10 wt %
together because in order to control the ratio of Ti and B, a
powder-type is not injected, but rather a natural formation in a
molten metal is induced using master aluminum alloys of Al--(in the
range of 5 to 10 wt %) Ti and Al--(in the range of 2 to 10 wt %) B,
so as to secure the material uniformity.
[0038] Table 2 represents the comparison of the phase fraction
according to the multi-element phase equilibrium calculation.
TABLE-US-00002 TABLE 2 Ti:B = 1:1 Ti:B = x:1 Alloy TiB.sub.2 Alloy
TiB.sub.2 B 1 wt % Al--1Ti--1B 1.45 Al--2.3Ti--1B 3.21 Content 2 wt
% Al--2Ti--2B 2.9 Al--4.5Ti--2B 6.3 3 wt % Al--3Ti--3B 4.36
Al--6.7Ti--3B 9.64
[0039] As shown Table 2, it is confirmed that the composition
containing the TiB.sub.2 single phase was changed by increasing the
B content, and the TiB.sub.2 production increased by increasing the
Ti/B ratio. Through this TiB.sub.2 increase, the elasticity
characteristics of the resulting material can be significantly
improved.
[0040] FIG. 1 is a graph comparing the TiB.sub.2 fractions of
aluminum alloys according to one exemplary embodiment of the
present invention, and it is confirmed that the phase fraction of
TiB.sub.2 increased by increasing the contents of B and Ti
(TiB.sub.2 is a part expressed as MB2 at the graph).
[0041] According to the aluminum alloy and the method for producing
the same consisting of the structure described above, the
elasticity and other properties (such as, e.g., strength,
wear-resistance, processability and the like) of the aluminum alloy
are improved by uniform distribution of the micro-TiB.sub.2 phase
and by maximization of boride production.
[0042] While the invention will be described in conjunction with
exemplary embodiments, it will be understood that present
description is not intended to limit the invention to those
exemplary embodiments. On the contrary, the invention is intended
to cover not only the exemplary embodiments, but also various
alternatives, modifications, equivalents and other embodiments,
which may be included within the spirit and scope of the invention
as defined by the appended claims.
* * * * *