U.S. patent application number 16/465321 was filed with the patent office on 2019-12-26 for semi-solid die-casting aluminum alloy and method for preparing semi-solid die-casting aluminum alloy casting.
The applicant listed for this patent is BYD COMPANY LIMITED. Invention is credited to Qiang GUO, Yongxi JIAN, Chunmeng ZHANG.
Application Number | 20190390305 16/465321 |
Document ID | / |
Family ID | 62241244 |
Filed Date | 2019-12-26 |
United States Patent
Application |
20190390305 |
Kind Code |
A1 |
JIAN; Yongxi ; et
al. |
December 26, 2019 |
SEMI-SOLID DIE-CASTING ALUMINUM ALLOY AND METHOD FOR PREPARING
SEMI-SOLID DIE-CASTING ALUMINUM ALLOY CASTING
Abstract
The present disclosure provides a semi-solid die-casting
aluminum alloy and a method for preparing a semi-solid die-casting
aluminum alloy casting. The semi-solid die-casting aluminum alloy
contains alloying elements, inevitable impurities and the balance
of aluminum element. Based on the total weight of the semi-solid
die-casting aluminum alloy, the alloying elements include: 7.5 to
9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01
to 0.5 wt % of Ti and 0.01 to 0.35 wt % of rare earth element.
Inventors: |
JIAN; Yongxi; (Shenzhen,
CN) ; ZHANG; Chunmeng; (Shenzhen, CN) ; GUO;
Qiang; (Shenzhen, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
BYD COMPANY LIMITED |
Shenzhen |
|
CN |
|
|
Family ID: |
62241244 |
Appl. No.: |
16/465321 |
Filed: |
November 16, 2017 |
PCT Filed: |
November 16, 2017 |
PCT NO: |
PCT/CN2017/111382 |
371 Date: |
May 30, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B22D 21/007 20130101;
C22C 1/026 20130101; C22C 1/03 20130101; C22C 21/02 20130101; B22D
17/007 20130101; B22D 17/00 20130101 |
International
Class: |
C22C 21/02 20060101
C22C021/02; B22D 21/00 20060101 B22D021/00; B22D 17/00 20060101
B22D017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 2, 2016 |
CN |
201611096735.4 |
Claims
1. A semi-solid die-casting aluminum alloy, comprising: alloying
elements, inevitable impurities, and a balance of aluminum element,
wherein based on a total weight of the semi-solid die-casting
aluminum alloy, the alloying elements comprise: 7.5 to 9.5 wt % of
Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt %
of Ti, and 0.01 to 0.35 wt % of rare earth element.
2. The semi-solid die-casting aluminum alloy according to claim 1,
wherein based on the total weight of the semi-solid die-casting
aluminum alloy, the alloying elements comprise: 8.0 to 9.0 wt % of
Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25 wt %
of Ti, and 0.15 to 0.25 wt % of rare earth element.
3. The semi-solid die-casting aluminum alloy according to claim 1,
wherein the rare earth element comprises at least one of La, Ce, Pr
and Nd.
4. The semi-solid die-casting aluminum alloy according to claim 1,
wherein the impurities in the semi-solid die-casting aluminum alloy
are not more than 0.8 wt %.
5. The semi-solid die-casting aluminum alloy according to claim 1,
wherein the ratio of the weight content of Ti to Cu is 1:(14 to
90).
6. The semi-solid die-casting aluminum alloy according to claim 4,
wherein the semi-solid die-casting aluminum alloy comprises 7.5 to
9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01
to 0.5 wt % Ti, 0.01 to 0.35 wt % of rare earth element, no more
than 0.8 wt % of impurities and the balance of aluminum.
7. The semi-solid die-casting aluminum alloy according to claim 6,
wherein the semi-solid die-casting aluminum alloy comprises 8.0 to
9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05
to 0.25 wt % Ti, 0.15 to 0.25 wt % of rare earth element, no more
than 0.7 wt % of impurities and the balance of aluminum.
8. The semi-solid die-casting aluminum alloy according to claim 1,
wherein the semi-solid die-casting aluminum alloy has a tensile
strength of not less than 370 MPa, a yield strength of not less
than 290 MPa, and an elongation of not less than 5.5%.
9. The semi-solid die-casting aluminum alloy according to claim 2,
wherein the semi-solid die-casting aluminum alloy has a tensile
strength of not less than 380 MPa, a yield strength of not less
than 300 MPa, and an elongation of not less than 6%.
10. A method for preparing a semi-solid die-casting aluminum alloy
casting, comprising: after performing ratio smelting on aluminum
alloy raw materials, performing semi-solid die casting to obtain
the semi-solid die-casting aluminum alloy casting, wherein the
aluminum alloy raw materials are such that the obtained semi-solid
die-casting aluminum alloy casting comprises: based on the total
weight of the aluminum alloy casting, 7.5 to 9.5 wt % of Si, 3.5 to
4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt % of Ti,
0.01 to 0.35 wt % of rare earth element, and the balance of
aluminum and inevitable impurities.
11. The method according to claim 10, wherein the aluminum alloy
raw materials are such that the obtained semi-solid die-casting
aluminum alloy casting comprises: based on the total weight of the
semi-solid die-casting aluminum alloy casting, 8.0 to 9.0 wt % of
Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25 wt %
of Ti, 0.15 to 0.25 wt % of rare earth element, and the balance of
aluminum and inevitable impurities.
12. The method according to claim 10, wherein the aluminum alloy
raw material is elemental metals or metal alloys.
13. The method according to claim 12, wherein the aluminum alloy
raw materials are elemental aluminum or an alloy of aluminum,
elemental silicon or an alloy of silicon, elemental copper or an
alloy of copper, elemental manganese or an alloy of manganese,
elemental titanium or an alloy of titanium, and an elemental rare
earth element or an alloy containing a rare earth element.
14. The method according to claim 12, wherein the aluminum alloy
raw materials are elemental aluminum, an Al--Si alloy, an Al--Ti
alloy, an Al--Cu alloy, an Al--Mn alloy and an Al--Re intermediate
alloy.
15. The method according to claim 12, wherein the purity of the
elemental metal is 99.9 wt % or more, and the total content of the
alloying elements in the metal alloy is 99.9 wt % or more.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of Chinese Patent
Application No. CN 201611096735.4 filed in China on Dec. 2, 2016,
the entire content of which is hereby incorporated by
reference.
TECHNOLOGY FIELD
[0002] The present disclosure relates to the field of alloys and,
in particular, to a semi-solid die-casting aluminum alloy and a
method for preparing a semi-solid die-casting aluminum alloy
casting.
BACKGROUND
[0003] Die casting is a liquid molding method. Due to the high
injection speed, the liquid easily forms turbulent flow in the mold
cavity, and the air in the mold cavity is drawn into the product.
When the liquid hits the mold, the temperature difference is large,
the liquid on the surface is rapidly solidified, which increases
the flow resistance of the core liquid, so it cannot be well fused
to form a cold partition. Due to the introduction of oxides or some
other impurities in the alloy smelting and casting process, the
product performance is ultimately lowered.
[0004] With the rapid development of 3C (Computer, communication,
and consumer electronics) and automotive products, die-casting
aluminum alloys have been rapidly applied. By the 1980s, 68% of
aluminum alloy components in the United States were produced by
die-casting technology. At present, the die-casting aluminum alloys
used in the industry mainly include aluminum-silicon alloys,
aluminum-magnesium alloys, aluminum-zinc alloys,
aluminum-silicon-copper alloys, and aluminum-silicon-magnesium
alloys.
[0005] The most commonly used die-casting alloy for die casting is
ADC12, which has a yield strength of about 190 MPa, a tensile
strength of about 280 MPa, and an elongation of 2 to 3%, and cannot
be strengthened by heat treatment. The wrought aluminum alloy
(including aluminum alloy for extrusion, forging, rolling, etc.)
has high mechanical properties and stable performance, but due to
the harsh process conditions and high equipment requirements, it is
impossible to form complicated parts, and it is impossible to
realize the demands of simplification and integration for
automobile parts.
SUMMARY
[0006] An objective of the present disclosure is to provide a
semi-solid die-casting aluminum alloy and a method for preparing a
semi-solid die-casting aluminum alloy casting. The semi-solid
die-casting aluminum alloy has high strength and high plasticity,
can be subjected to high pressure casting, and can form various
complicated parts and ensure high mechanical properties.
[0007] To achieve the above objective, the present disclosure
provides a semi-solid die-casting aluminum alloy, containing
alloying elements, inevitable impurities and the balance of an
aluminum element; based on the total weight of the semi-solid
die-casting aluminum alloy, the alloying elements include: 7.5 to
9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01
to 0.5 wt % of Ti and 0.01 to 0.35 wt % of rare earth element.
[0008] Optionally, based on the total weight of the semi-solid
die-casting aluminum alloy, the alloying elements include: 8.0 to
9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05
to 0.25 wt % of Ti and 0.15 to 0.25 wt % of rare earth element.
[0009] Optionally, the rare earth element includes at least one of
La, Ce, Pr and Nd.
[0010] Optionally, the impurities in the semi-solid die-casting
aluminum alloy are not more than 0.8 wt %.
[0011] Optionally, the ratio of the weight content of Ti to Cu is
1:(14 to 90).
[0012] Optionally, the semi-solid die-casting aluminum alloy
includes 7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75
wt % of Mn, 0.01 to 0.5 wt % Ti, 0.01 to 0.35 wt % of rare earth
element, no more than 0.8 wt % of impurities and the balance of
aluminum.
[0013] Optionally, the semi-solid die-casting aluminum alloy
includes 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6
wt % of Mn, 0.05 to 0.25 wt % Ti, 0.15 to 0.25 wt % of rare earth
element, no more than 0.7 wt % of impurities and the balance of
aluminum.
[0014] Optionally, the semi-solid die-casting aluminum alloy has a
tensile strength of not less than 370 MPa, a yield strength of not
less than 290 MPa, and an elongation of not less than 5.5%.
[0015] Optionally, the semi-solid die-casting aluminum alloy has a
tensile strength of not less than 380 MPa, a yield strength of not
less than 300 MPa, and an elongation of not less than 6%.
[0016] The present disclosure further provides a method for
preparing a semi-solid die-casting aluminum alloy casting,
including: after performing ratio smelting on aluminum alloy raw
materials, performing semi-solid die casting to obtain the
semi-solid die-casting aluminum alloy casting; where the aluminum
alloy raw materials are such that the obtained semi-solid
die-casting aluminum alloy casting includes: based on the total
weight of the semi-solid die-casting aluminum alloy casting, 7.5 to
9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01
to 0.5 wt % of Ti, 0.01 to 0.35 wt % of rare earth element, and the
balance of aluminum and inevitable impurities.
[0017] Optionally, the aluminum alloy raw materials are such that
the obtained semi-solid die-casting aluminum alloy casting
includes: based on the total weight of the semi-solid die-casting
aluminum alloy casting, 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of
Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25 wt % of Ti, 0.15 to 0.25 wt
% of rare earth element, and the balance of aluminum and inevitable
impurities.
[0018] Optionally, the aluminum alloy raw materials are elemental
metals or metal alloys.
[0019] Optionally, the aluminum alloy raw materials are elemental
aluminum or an alloy of aluminum, elemental silicon or an alloy of
silicon, elemental copper or an alloy of copper, elemental
manganese or an alloy of manganese, elemental titanium or an alloy
of titanium, and an elemental rare earth element or an alloy
containing a rare earth element.
[0020] Optionally, the aluminum alloy raw materials are elemental
aluminum, an Al--Si alloy, an Al--Ti alloy, an Al--Cu alloy, an
Al--Mn alloy and an Al--Re intermediate alloy.
[0021] Optionally, the purity of the elemental metal is 99.9 wt %
or more, and the total content of the alloying elements in the
metal alloy is 99.9 wt % or more.
[0022] Through the above technical solutions, according to the
semi-solid die-casting aluminum alloy of the present disclosure,
the adjustment and optimization of the formula and the addition of
rare earth elements have the purification effect of removing gases
and impurities and the modification effect of refining crystal
grains on the alloy melt, and also increase the melt fluidity and
enhance the casting properties. The method for preparing a
semi-solid die-casting aluminum alloy casting of the present
disclosure adopts the above semi-solid die-casting aluminum alloy
for semi-solid die casting. The method can form various complicated
components, enhances the mechanical properties of the casting,
reduces the defects of the casting, and enhances the yield.
[0023] Other features and advantages of the present disclosure will
be described in detail in the detailed description which
follows.
DETAILED DESCRIPTION
[0024] Specific implementations of the present disclosure are
described in detail below. It should be understood that the
specific implementations described herein are merely illustrative
of the present disclosure and are not intended to limit the present
disclosure.
[0025] The present disclosure provides a semi-solid die-casting
aluminum alloy, containing alloying elements, inevitable impurities
and the balance of an aluminum element; based on the total weight
of the semi-solid die-casting aluminum alloy, the alloying elements
include: 7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75
wt % of Mn, 0.01 to 0.5 wt % of Ti and 0.01 to 0.35 wt % of rare
earth element.
[0026] According to the semi-solid die-casting aluminum alloy of
the present disclosure, the adjustment and optimization of the
formula and the addition of rare earth elements have the
purification effect of removing gases and impurities and the
modification effect of refining crystal grains on the alloy melt,
and also increase the melt fluidity and enhance the casting
properties. According to the semi-solid die-casting aluminum alloy
of the present disclosure, when the composition of the semi-solid
die-casting aluminum alloy is within the above range, high
mechanical properties can be obtained while good casting properties
are obtained. The semi-solid die-casting aluminum alloy obtained by
using the formula has a tensile strength of not less than 370 MPa,
a yield strength of not less than 290 MPa, and an elongation of not
less than 5.5%.
[0027] According to the present disclosure, to further enhance the
mechanical properties and casting properties of the semi-solid
die-casting aluminum alloy, optionally, based on the total weight
of the semi-solid die-casting aluminum alloy, the alloying elements
include: 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6
wt % of Mn, 0.05 to 0.25 wt % of Ti and 0.15 to 0.25 wt % of rare
earth element. The semi-solid die-casting aluminum alloy obtained
according to the formula has a tensile strength of not less than
380 MPa, a yield strength of not less than 300 MPa, and an
elongation of not less than 6%.
[0028] According to the present disclosure, the kind of the rare
earth element is not particularly limited, may be a conventional
kind well known to those skilled in the art, and may be a single
kind of rare earth element or mixed rare earths. To reduce the raw
material cost, optionally, the rare earth element may include at
least one of La, Ce, Pr and Nd, and the relative content of each
rare earth element is also not particularly required. The above
rare earth element may be a commercially available product and is
industrial mixed rare earths.
[0029] According to the present disclosure, the purity of the
semi-solid die-casting aluminum alloy is one of the important
factors affecting the performance of the aluminum alloy. To make
the semi-solid die-casting aluminum alloy of the present disclosure
excellent in performance, optionally, the impurities in the
semi-solid die-casting aluminum alloy are not more than 0.8 wt
%.
[0030] According to the present disclosure, the addition of the
metal element titanium in the semi-solid die-casting aluminum alloy
can refine the crystal grains, enhance the strength and plasticity
of the alloy, improve the fluidity of the alloy and enhance the
casting properties. At the same time, the added metal element
copper can form a Ti.sub.2Cu.sub.3 phase with titanium and be
distributed at the grain boundary, so that the grain boundary slip
during alloy stretching is effectively suppressed, thereby
enhancing the strength of the alloy. To further enhance of the
effect of enhancing the performance of the semi-solid die-casting
aluminum alloy by the above two elements, optionally, the ratio of
the weight content of Ti to Cu may be 1:(7 to 350), preferably
1:(14 to 90).
[0031] To further enhance the mechanical properties and casting
properties of the semi-solid die-casting aluminum alloy,
optionally, the semi-solid die-casting aluminum alloy may include
7.5 to 9.5 wt % of Si, 3.5 to 4.8 wt % of Cu, 0.5 to 0.75 wt % of
Mn, 0.01 to 0.5 wt % Ti, 0.01 to 0.35 wt % of rare earth element,
no more than 0.8 wt % of impurities and the balance of
aluminum.
[0032] Optionally, the semi-solid die-casting aluminum alloy may
include 8.0 to 9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt
% of Mn, 0.05 to 0.25 wt % Ti, 0.15 to 0.25 wt % of rare earth
element, no more than 0.7 wt % of impurities and the balance of
aluminum.
[0033] The present disclosure further provides a method for
preparing a semi-solid die-casting aluminum alloy casting,
including: after performing ratio smelting on aluminum alloy raw
materials, performing semi-solid die casting to obtain the
semi-solid die-casting aluminum alloy casting, where the aluminum
alloy raw materials are such that the obtained semi-solid
die-casting aluminum alloy casting includes: based on the total
weight of the aluminum alloy casting, 7.5 to 9.5 wt % of Si, 3.5 to
4.8 wt % of Cu, 0.5 to 0.75 wt % of Mn, 0.01 to 0.5 wt % of Ti,
0.01 to 0.35 wt % of rare earth element, and the balance of
aluminum and inevitable impurities.
[0034] According to the method for preparing a semi-solid
die-casting aluminum alloy casting of the present disclosure, to
obtain a semi-solid die-casting aluminum alloy casting having
higher mechanical properties, in an optional case, the aluminum
alloy raw materials are such that the obtained semi-solid
die-casting aluminum alloy casting includes: based on the total
weight of the semi-solid die-casting aluminum alloy casting, 8.0 to
9.0 wt % of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05
to 0.25 wt % of Ti, 0.15 to 0.25 wt % of rare earth element, and
the balance of aluminum and inevitable impurities.
[0035] According to the method for preparing a semi-solid
die-casting aluminum alloy casting of the present disclosure, the
melting may be performed in a smelting furnace, and the aluminum
alloy raw materials added to the smelting furnace may be simple
substances or metal alloys, as long as the composition of the
aluminum alloy obtained by smelting the added aluminum alloy raw
materials is within the above range. In an optional case, the
aluminum alloy raw materials may be elemental aluminum or an alloy
of aluminum, elemental silicon or an alloy of silicon, elemental
copper or an alloy of copper, elemental manganese or an alloy of
manganese, elemental titanium or an alloy of titanium, and an
elemental rare earth element or an alloy containing a rare earth.
In an optional case, the above aluminum alloy raw materials are
elemental aluminum, an Al--Si alloy, an Al--Ti alloy, an Al--Cu
alloy, an Al--Mn alloy and an Al--Re intermediate alloy. Further,
to prevent the introduction of impurities from affecting the
performance of the aluminum alloy, the purity of the elemental
metal is 99.9 wt % or more, and the total content of the alloying
elements in the alloy is 99.9 wt % or more.
[0036] According to the method for preparing a semi-solid
die-casting aluminum alloy casting of the present disclosure, the
semi-solid die-casting aluminum alloy casting is obtained by
performing semi-solid die casting after performing ratio smelting
on the aluminum alloy raw materials. The smelting and semi-solid
die casting can employ conventional methods and operating
conditions, and the present disclosure does not impose any
particular requirements.
[0037] For example, the smelting process may adopt the existing
steps of material
preparation.fwdarw.melting.fwdarw.refining.fwdarw.slag
removing.fwdarw.casting. Specifically, the method for preparing a
semi-solid die-casting aluminum alloy casting of the present
disclosure may include the following steps:
[0038] Step 1: Material preparation: 1) raw materials: a pure
aluminum ingot (purity.gtoreq.99.9 wt %), an Al--Si intermediate
alloy, an Al--Ti intermediate alloy, an Al--Cu intermediate alloy,
an Al--Mn intermediate alloy and an Al--Re intermediate alloy; and
2) fluxes: a covering agent, a refining agent and a modifier, which
may be the existing covering agent, refining agent and modifier for
aluminum alloy preparation, for example, the covering agent SY-LF1,
the refining agent hexachloroethane and the modifier K2ZrF6.
[0039] Step 2: Drying: the prepared raw materials are dried, where
the pure aluminum ingot is dried at a temperature of 100.degree.
C..+-.10.degree. C., the Al--Si intermediate alloy, the Al--Ti
intermediate alloy, the Al--Cu intermediate alloy, the Al--Mn
intermediate alloy and the Al--Re intermediate alloy are dried at a
temperature of 150.degree. C..+-.10.degree. C., and the purpose of
drying is to remove moisture from the raw materials.
[0040] Step 3: Melt alloying: the inner wall of a crucible is
coated with the prepared covering agent, the crucible is preheated
to 200 to 250.degree. C., the weighed aluminum ingot, Al--Si
intermediate alloy, Al--Ti intermediate alloy, Al--Cu intermediate
alloy, Al--Mn intermediate alloy and Al--Re intermediate alloy
ingot are placed into the crucible, and heated and melted after the
addition of the covering agent, and the alloys are stirred
uniformly after fully melted, where the time of the entire melting
process is controlled within 2 to 3 h, and the final temperature of
the aluminum alloy melt is controlled at 750 to 770.degree. C.
[0041] Step 4: Refining: the purpose of refining is to remove
non-metallic inclusions in the alloy liquid; at 700 to 720.degree.
C., a bell jar is used to press the refining agent hexachloroethane
into about 2/3 below the surface of the melt in batches, and is
rotated clockwise uniformly and slowly, and when the
hexachloroethane is fully reacted, the inclusions and gases in the
melt are taken out. The speed of stirring is low. The amount of
hexachloroethane is related to the alloy composition and the mass
of the original ingot, and is generally 0.5 wt % to 0.7 wt % of the
charge. Melting is performed in a resistance furnace, and the
refining time is within 10 min.
[0042] Step 5: Slag removing: after fully refining with the
hexachloroethane, the bell jar is taken out, the residual oxides
are removed, and the inclusions on the surface of the melt are
removed with a slag spoon.
[0043] Step 6: Casting: after the alloy slag is removed, pouring
should be immediately performed after 4 to 10 min of heat
preservation to obtain an alloy ingot for die casting or a die-cast
block. The pouring temperature is generally required to be 720 to
750.degree. C.
[0044] Step 7: Die Casting: the above-mentioned alloy ingot for die
casting or die-cast block is die-cast into a sample by a
conventional semi-solid die casting process, thereby obtaining the
aluminum alloy casting of the present disclosure.
[0045] The aluminum alloy and a method for preparing the same of
the present disclosure are further described below by way of
embodiments. However, the present disclosure is not limited to the
embodiments listed below.
[0046] In the following embodiments and comparative examples of the
present disclosure, the rare earth element is mixed rare earths
(containing 39.8 wt % of La and 58.8 wt % of Ce).
Embodiment 1
[0047] This embodiment is for explaining a semi-solid die-casting
aluminum alloy and a method for preparing a semi-solid die-casting
aluminum alloy casting of the present disclosure.
[0048] The semi-solid die-casting aluminum alloy included: based on
the total weight of the semi-solid die-casting aluminum alloy, 8.5
wt % of Si, 4.0 wt % of Cu, 0.55 wt % of Mn, 0.15 wt % of Ti, 0.20
wt % of rare earth element, and the balance of aluminum.
[0049] The aluminum ingot, the Al--Si intermediate alloy, the
Al--Ti intermediate alloy, the Al--Cu intermediate alloy, the
Al--Mn intermediate alloy and the Al--Re intermediate alloy ingot
measured according to the above semi-solid die-casting aluminum
alloy composition were placed into a crucible coated with a
covering agent and preheated to 220.degree. C., and were heated and
melted after the addition of the covering agent, and the alloys
were stirred uniformly after fully melted, where the melting
process was 2.5 h, and the final temperature of the aluminum alloy
melt was 750.degree. C.; at 700 to 720.degree. C., a bell jar was
used to press the refining agent hexachloroethane into about 2/3
below the surface of the melt in batches, and was rotated clockwise
uniformly and slowly, for refining for 8 min where the amount of
hexachloroethane was 0.5 wt % of the charge; after fully refining,
the bell jar was taken out, the residual oxides were removed, and
the inclusions on the surface of the melt were removed with a slag
spoon; after 5 min of heat preservation, pouring was performed to
obtain an aluminum alloy ingot Z1, where the pouring temperature
was 750.degree. C.; and the above aluminum alloy ingot Z1 was
die-cast into a sample by a conventional semi-solid die casting
process, thereby obtaining the aluminum alloy casting Al of this
embodiment.
Embodiment 2
[0050] This embodiment is for explaining a semi-solid die-casting
aluminum alloy and a method for preparing a semi-solid die-casting
aluminum alloy casting of the present disclosure.
[0051] The method of Embodiment 1 was employed, except that the
semi-solid die-casting aluminum alloy included: based on the total
weight of the semi-solid die-casting aluminum alloy, 9.5 wt % of
Si, 3.5 wt % of Cu, 0.5 wt % of Mn, 0.01 wt % of Ti, 0.01 wt % of
rare earth element and the balance of aluminum, thereby obtaining
the aluminum alloy casting A2 of this embodiment.
Embodiment 3
[0052] This embodiment is for explaining a semi-solid die-casting
aluminum alloy and a method for preparing a semi-solid die-casting
aluminum alloy casting of the present disclosure.
[0053] The method of Embodiment 1 was employed, except that the
semi-solid die-casting aluminum alloy included: based on the total
weight of the semi-solid die-casting aluminum alloy, 7.5 wt % of
Si, 4.8 wt % of Cu, 0.75 wt % of Mn, 0.5 wt % of Ti, 0.35 wt % of
rare earth element and the balance of aluminum, thereby obtaining
the aluminum alloy casting A3 of this embodiment.
Embodiment 4
[0054] This embodiment is for explaining a semi-solid die-casting
aluminum alloy and a method for preparing a semi-solid die-casting
aluminum alloy casting of the present disclosure.
[0055] The method of Embodiment 1 was employed, except that the
semi-solid die-casting aluminum alloy included: based on the total
weight of the semi-solid die-casting aluminum alloy, 9.0 wt % of
Si, 4.4 wt % of Cu, 0.52 wt % of Mn, 0.10 wt % of Ti, 0.15 wt % of
rare earth element and the balance of aluminum, thereby obtaining
the aluminum alloy casting A4 of this embodiment.
Comparative Example 1
[0056] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0057] The method and the raw materials of Embodiment 1 were
employed except that no rare earth element was added, thereby
obtaining the aluminum alloy casting B1 of this comparative
example.
Comparative Example 2
[0058] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0059] The method and the raw materials of Embodiment 1 were
employed except that the content of the rare earth element in the
semi-solid die-casting aluminum alloy was 0.5 wt %, thereby
obtaining the aluminum alloy casting B2 of this comparative
example.
Comparative Example 3
[0060] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing the aluminum
alloy casting different from the present disclosure.
[0061] The method and the raw materials of Embodiment 1 were
employed except that the content of the Si in the semi-solid
die-casting aluminum alloy was 10 wt %, thereby obtaining the
aluminum alloy casting B3 of this comparative example.
Comparative Example 4
[0062] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0063] The method and the raw materials of Embodiment 1 were
employed except that the content of the Si in the semi-solid
die-casting aluminum alloy was 7 wt %, thereby obtaining the
aluminum alloy casting B4 of this comparative example.
Comparative Example 5
[0064] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing the aluminum
alloy casting different from the present disclosure.
[0065] The method and the raw materials of Embodiment 1 were
employed except that the content of the Cu in the semi-solid
die-casting aluminum alloy was 5 wt %, thereby obtaining the
aluminum alloy casting B5 of this comparative example.
Comparative Example 6
[0066] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0067] The method and the raw materials of Embodiment 1 were
employed except that the content of the Cu in the semi-solid
die-casting aluminum alloy was 3 wt %, thereby obtaining the
aluminum alloy casting B6 of this comparative example.
Comparative Example 7
[0068] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0069] The method of Embodiment 1 was employed except that a
commercially available ADC12 aluminum alloy ingot was used as the
ingot, thereby obtaining the aluminum alloy sample B7.
Comparative Example 8
[0070] This comparative example is for explaining a semi-solid
die-casting aluminum alloy and a method for preparing an aluminum
alloy casting different from the present disclosure.
[0071] The method of Embodiment 1 was employed except that a
commercially available A356.2 aluminum alloy ingot was used as the
ingot, thereby obtaining the aluminum alloy sample B8.
Comparative Example 9
[0072] This comparative example is for explaining a die-casting
aluminum alloy and a method for preparing an aluminum alloy casting
different from the present disclosure.
[0073] The raw materials of Embodiment 1 were employed except that
a conventional die casting method was used, thereby obtaining the
aluminum alloy sample B9.
Comparative Example 10
[0074] This comparative example is for explaining a die-casting
aluminum alloy and a method for preparing an aluminum alloy casting
different from the present disclosure.
[0075] Pure aluminum (A00 aluminum), an aluminum-manganese alloy
(AlMn10), an aluminum-silicon alloy (AlSi12), an aluminum-iron
alloy (AlFe10), an aluminum-copper alloy (Al-50Cu), pure magnesium
(99.9), pure zinc (99.95), an aluminum-titanium-carbon-boron alloy,
magnesium-lanthanum-cerium (Mg--LaCe) and magnesium-yttrium (Mg--Y)
were subjected to mixture calculation, smelting and pouring. The
contents of the main elements of the finally obtained alloy were as
follows: Si: 6.0 wt %, Cu: 0.5 wt %, Fe: 0.42 wt %, Mn: 0.05 wt %,
Mg: 1.0 wt %, Zn: 1.5 wt %, Ti: 0.05 wt %, C: 0.002 wt %, LaCe:
0.20 wt %, Y: 0.12 wt %, and the balance of Al and inevitable
impurities. A conventional die casting method was employed to
obtain the aluminum alloy sample B10.
Comparative Example 11
[0076] This comparative example is for explaining a die-casting
aluminum alloy and a method for preparing an aluminum alloy casting
different from the present disclosure.
[0077] (1) A pure magnesium ingot and intermediate alloys Al--Si,
Al--Mn, Al--Cu, Al--Ti were preheated to 180 to 240.degree. C., the
temperature was kept within the range of 740 to 760.degree. C.
after pure aluminum was melted, the pure magnesium ingot and the
intermediate alloys Al--Si, Al--Mn, Al--Cu, Al--Ti were
sequentially added into the aluminum liquid, and after being
melted, they were kept at 740.degree. C. for 30 minutes to be
sufficiently homogenized, where the weight percents of the
ingredients in the above materials were Si: 8.5 to 11.5%, Mn: 0.1
to 0.8%, Cu: 0.5 to 3.0%, Mg: 0.25 to 0.5%, Ti: 0.15 to 0.35%, and
other impurities.ltoreq.0.4% (where Fe<0.8%, P<0.004%).
[0078] (2) The temperature of the alloy liquid was raised to
780.degree. C., the mixed rare earths were added, the surface scum
was removed after the mixed rare earths were melted, the mixture
was stirred for 3 to 6 minutes to homogenize the composition, and
after stirring, the temperature of the alloy liquid was raised to
770 to 780.degree. C., and then kept to stand for 30 minutes, where
the total weight of the mixed rare earths is not more than 1%, and
each of La, Ce, Sm and Nd is less than 0.35% by weight.
[0079] (3) After the alloy liquid was cooled to 750.degree. C. and
refined for 15 minutes, the alloy liquid was cooled to 710.degree.
C. and subjected to slag removal, then the alloy liquid was cooled
to 690.degree. C. and subjected to gas removal, finally the alloy
liquid after slag removal and gas removal was cooled to at
680.degree. C. and subjected to die casting, and the heat treatment
process was performed after the casting was formed. The casting was
subjected to solution treatment at a temperature of higher than
545.degree. C. for 3 hours, and then subjected to aging treatment
at a temperature of 165.degree. C. for 6 to 12 hours, thereby
obtaining the aluminum alloy sample B11.
[0080] Test
[0081] This test was used to determine the mechanical properties of
the semi-solid die-casting aluminum alloy castings obtained in
Embodiments 1 to 4 and Comparative Examples 1 to 11 at room
temperature.
[0082] For the tensile strength, yield strength and elongation of
the aluminum alloy castings tested with reference to "GB/T
228.1-2010 Metallic Materials-Tensile Testing-Part 1: Method of
test at room temperature", the specific results are shown in Table
1.
TABLE-US-00001 TABLE 1 Yield Strength Breaking Strength Elongation
Embodiment (MPa) (MPa) (%) Embodiment 1 310 392 8.5 Embodiment 2
300 371 7.0 Embodiment 3 291 376 5.5 Embodiment 4 305 385 8.0
Comparative example 1 254 332 5.5 Comparative example 2 296 367 7.0
Comparative example 3 280 371 6.0 Comparative example 4 261 323 5.0
Comparative example 5 290 342 4.0 Comparative example 6 243 296 5.0
Comparative example 7 185 292 2.5 Comparative example 8 251 310 8.0
Comparative example 9 174 278 2 Comparative example 10 200 300 6.2
Comparative example 11 230 308 5.0
[0083] It can be seen from the comparison of the results of
Embodiments 1 to 4 and Comparative Examples 1 to 11 that the
semi-solid die-casting aluminum alloy of the present disclosure has
good mechanical properties and casting properties, and the
semi-solid die-casting aluminum alloy has a tensile strength of not
less than 370 MPa, a yield strength of not less than 290 MPa, and
an elongation of not less than 5.5%. In particular, the optional
alloying elements in the present disclosure include: 8.0 to 9.0 wt
% of Si, 3.5 to 4.5 wt % of Cu, 0.5 to 0.6 wt % of Mn, 0.05 to 0.25
wt % of Ti and 0.15 to 0.25 wt % of rare earth element, the
semi-solid die-casting aluminum alloy obtained according to the
formula has a tensile strength of not less than 380 MPa, a yield
strength of not less than 300 MPa, and an elongation of not less
than 6%. It can be seen from the comparison of the data of
Embodiment 1 and Embodiment 4 with Embodiments 2 to 3 that in the
case where the ratio of the weight content of Ti to Cu of the
present disclosure is 1:(14 to 90), the semi-solid die-casting
aluminum alloy of the present disclosure has better mechanical
properties and casting properties.
[0084] Although optional implementations of the present disclosure
are described in detail above, the present disclosure is not
limited to specific details in the foregoing implementations.
Various variations can be made to the technical solutions of the
present disclosure within the scope of the technical idea of the
present disclosure, and such variations all fall within the
protection scope of the present disclosure.
[0085] It should be further noted that the specific technical
features described in the foregoing specific implementations can be
combined in any appropriate manner provided that no conflict
occurs. To avoid unnecessary repetition, various possible
combination manners are not further described in the present
disclosure.
[0086] In addition, various different implementations of the
present disclosure may alternatively be combined randomly. Such
combinations should also be considered as the content disclosed in
the present disclosure provided that these combinations do not
depart from the concept of the present disclosure.
* * * * *