U.S. patent application number 15/092816 was filed with the patent office on 2016-10-13 for aluminum alloy refiner material and preparation method thereof.
This patent application is currently assigned to CITIC Dicastal CO., LTD. The applicant listed for this patent is CITIC Dicastal CO., LTD. Invention is credited to Lateng A, Chunnian He, Changhai Li, Chunhai Liu, Yungao Su, Lisheng Wang, Yongning Wang, Zhendong Zhang, Naiqin Zhao, Shengli Zhu, Zhihua Zhu.
Application Number | 20160298217 15/092816 |
Document ID | / |
Family ID | 53644652 |
Filed Date | 2016-10-13 |
United States Patent
Application |
20160298217 |
Kind Code |
A1 |
Wang; Lisheng ; et
al. |
October 13, 2016 |
Aluminum Alloy Refiner Material and Preparation Method Thereof
Abstract
The present invention provides an aluminum alloy refiner, which
is characterized by being an amorphous alloy comprising 40 to 60
parts of Zr, 25 to 45 parts of Cu, 1 to 15 parts of Al, 1 to 10
parts of Pd and 1 to 10 parts of Nb in terms of mass fraction. The
refiner provided by the present invention can be used to favorably
refine crystal grains as well as improve the mechanical property of
the aluminum alloy to a certain extent. Moreover, the intermediate
alloy improves the strength and plasticity of the alloy, and a
refined A356 aluminum alloy is very suitable for the manufacturing
of automobile wheels.
Inventors: |
Wang; Lisheng; (Qinhuangdao,
CN) ; Wang; Yongning; (Qinhuangdao, CN) ; Zhu;
Zhihua; (Qinhuangdao, CN) ; Liu; Chunhai;
(Qinhuangdao, CN) ; Li; Changhai; (Qinhuangdao,
CN) ; A; Lateng; (Qinhuangdao, CN) ; Zhang;
Zhendong; (Qinhuangdao, CN) ; Su; Yungao;
(Qinhuangdao, CN) ; Zhao; Naiqin; (Qinhuangdao,
CN) ; Zhu; Shengli; (Qinhuangdao, CN) ; He;
Chunnian; (Qinhuangdao, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CITIC Dicastal CO., LTD |
Qinhuangdao |
|
CN |
|
|
Assignee: |
CITIC Dicastal CO., LTD
Qinhuangdao
CN
|
Family ID: |
53644652 |
Appl. No.: |
15/092816 |
Filed: |
April 7, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C22C 45/10 20130101;
C22C 1/002 20130101; C22F 1/002 20130101; C22C 1/03 20130101; C22C
1/02 20130101; C22F 1/186 20130101 |
International
Class: |
C22C 45/10 20060101
C22C045/10; C22F 1/18 20060101 C22F001/18; C22C 1/00 20060101
C22C001/00; C22F 1/00 20060101 C22F001/00; C22C 1/02 20060101
C22C001/02; C22C 1/03 20060101 C22C001/03 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 9, 2015 |
CN |
201510165958.0 |
Claims
1. An aluminum alloy refiner, comprising: an amorphous alloy
comprising 40 to 60 parts of Zr, 25 to 45 parts of Cu, 1 to 15
parts of Al, 1 to 10 parts of Pd and 1 to 10 parts of Nb in terms
of mass fraction.
2. The aluminum alloy refiner according to claim 1, wherein the
aluminum alloy refiner is one of the following: the amorphous alloy
comprising 50 parts of Zr, 35 parts of Cu, 7 parts of Al, 5 parts
of Pd and 3 parts of Nb in terms of mass fraction; the amorphous
alloy comprising 40 parts of Zr, 45 parts of Cu, 1 part of Al, 10
parts of Pd and 1 part of Nb in terms of mass fraction; the
amorphous alloy comprising 60 parts of Zr, 25 parts of Cu, 15 parts
of Al, 1 part of Pd and 10 parts of Nb in terms of mass fraction;
the amorphous alloy comprising 52 parts of Zr, 29 parts of Cu, 7
parts of Al, 7 parts of Pd and 3 parts of Nb in terms of mass
fraction; and the amorphous alloy comprising 57 parts of Zr, 41
parts of Cu, 12 parts of Al, 5 parts of Pd and 1 part of Nb in
terms of mass fraction.
3. The aluminum alloy refiner according to claim 1, wherein the
aluminum alloy refiner is prepared through rapid cooling.
4. The aluminum alloy refiner according to claim 3, wherein the
rapid cooling is to melt Zr, Cu, Al, Pd and Nb at the temperature
of 900 to 1000 degrees and prepare the aluminum alloy refiner by a
single-roll melt spinner.
5. An aluminum alloy refiner, prepared with a method as follows:
(1) mixing pure metals of Zr, Cu, Al, Pd and Nb according to a
certain proportion, pre-vacuumizing a vacuum electric arc furnace
to be below 10.sup.-3Pa, charging an argon gas for smelting, and
repeatedly smelting 5 times to prepare a master alloy with even
components; and (2) breaking the master alloy from step (1) into
small lumps, placing the small lumps into a quartz tube,
pre-vacuumizing a single-roll melt spinner to be below 10.sup.-3Pa,
charging the argon gas to melt the master alloy in the quartz tube
through induction heating, with the temperature of molten alloy of
900 to 1000 degrees, regulating the rotation speed of a copper roll
to be 3000 to 4000 r/min, and spraying the molten alloy out to the
surface of the copper roll by using the argon gas, thereby
preparing an amorphous alloy ribbon.
6. The aluminum alloy refiner according to claim 5, wherein the
partial pressure of the argon gas in the step (1) is 0.02 to 0.05
Mpa.
7. The aluminum alloy refiner according to claim 5, wherein the
partial pressure of the argon gas in the step (2) is 0.05 to 0.1
Mpa.
8. A method for preparing the Zr-Cu-Al-Pd-Nb amorphous alloy
according to claim 1, comprising the following steps: (1) mixing
pure metals of Zr, Cu, Al, Pd and Nb according to a certain
proportion, pre-vacuumizing a vacuum electric arc furnace to be
below 10.sup.-3Pa, charging an argon gas for smelting, and
repeatedly smelting 5 times to prepare a master alloy with even
components; and (2) breaking the master alloy from the step (1)
into small lumps, placing the small lumps into a quartz tube,
pre-vacuumizing a single-roll melt spinner to be below 10.sup.-3Pa,
charging the argon gas to melt the master alloy in the quartz tube
through induction heating, with the temperature of molten alloy of
900 to 1000 degrees, regulating the rotation speed of a copper roll
to be 3000 to 4000 r/min, and spraying the molten alloy out to the
surface of the copper roll by using the argon gas, thereby
preparing an amorphous alloy ribbon.
9. The method according to claim 8, wherein the partial pressure of
the argon gas in the step (1) is 0.02 to 0.05 Mpa.
10. The method according to claim 8, wherein the partial pressure
of the argon gas in the step (2) is 0.05 to 0.1 Mpa.
Description
TECHNICAL FIELD
[0001] The present invention relates to the field of smelting of
aluminum alloys, and in particular to an alloy refiner material for
refining an aluminum alloy.
BACKGROUND ART
[0002] Aluminum is the most abundant metal element reserved in the
earth crust, has the characteristics of small density, high
plasticity, good ductility and excellent casting performance and is
good in corrosion resistance due to a dense oxidiation film for
surface protection. Cast aluminum alloy is prepared by adding other
metal or non-metal elements on the basis of pure aluminum, not only
maintaining the basic properties of the pure aluminum, but also
possessing excellent comprehensive performance due to the effects
of alloying and thermal treatment. Al-Si cast alloy takes Si as a
major secondary element, with the Si content controlled to be 4% to
22%. Al-Si based alloy has good casting properties (such as
liquidity, shrinkage percentage, thermal cracking resistance, and
air tightness). A356 alloy belongs to Al-Si based alloy and is
widely applied to casting of various casing parts, automobile
wheels, aircraft pumps, aircraft accessories, automobile
transmissions, car chassis accessories and the like due to the
excellent comprehensive performance thereof.
[0003] At present, A356 aluminum alloy has been often adopted in
the international automobile industry to cast various wheels. A356
aluminum alloy is an Al-Si-Mg based alloy, with primary .alpha.-Al
and an eutectic structure as a major structure (.alpha.-Al+eutectic
Si), wherein eutectic silicon takes a coarse acicular shape, and a
structure taking the coarse acicular shape will severely split a
matrix and reduce the mechanical property of the alloy. Therefore,
modification treatment is needed to improve the structure form
thereof to further improve the mechanical property of the alloy.
The present invention is intended to develop a novel modifier.
Accordingly, at present, there is an urgent need of a refiner,
which meets the chemical requirements of A356.2 alloy and is
capable of improving the structure as well as the mechanical
property of the A356.2 alloy to meet the requirement of wheel
production.
SUMMARY OF THE INVENTION
[0004] Therefore, an object of the present invention is to provide
a refiner, which meets the chemical requirements of A356.2 alloy,
and is capable of improving the structure as well as the mechanical
property of the A356.2 alloy to meet the requirement of wheel
production.
[0005] In order to achieve the object described above, the present
invention provides a technical solution as follows.
[0006] In one aspect of the present invention, an aluminum alloy
refiner is provided, which is characterized by being an amorphous
alloy comprising 40 to 60 parts of Zr, 25 to 45 parts of Cu, 1 to
15 parts of Al, 1 to 10 parts of Pd and 1 to 10 parts of Nb in
terms of mass fraction.
[0007] In one preferable aspect of the present invention, the
aluminum alloy refiner comprises 50 parts of Zr, 35 parts of Cu, 7
parts of Al, 5 parts of Pd and 3 parts of Nb in terms of mass
fraction.
[0008] In one preferable aspect of the present invention, the
aluminum alloy refiner is prepared through rapid cooling.
[0009] In one preferable aspect of the present invention, the rapid
cooling is to melt Zr, Cu, Al, Pd and Nb at the temperature of 900
to 1000.degree. C. and the refiner is prepared by a single-roll
melt spinner.
[0010] In one preferable aspect of the present invention, the
aluminum alloy refiner is prepared with a method including the
following steps:
[0011] (1) mixing pure metals of Zr, Cu, Al, Pd and Nb according to
a certain proportion, pre-vacuumizing a vacuum electric arc furnace
to be below 10.sup.-3Pa, charging an argon gas (preferably under a
partial pressure of 0.02 to 0.05 MPa) for smelting, and repeatedly
smelting 5 times to prepare a master alloy with even components;
and
[0012] (2) breaking the master alloy from the step (1) into small
lumps, placing the small lumps into a quartz tube, pre-vacuumizing
a single-roll melt spinner to be below 10.sup.-3Pa, charging the
argon gas (preferably under a partial pressure of 0.05 to 0.1 MPa)
to melt the master alloy in the quartz tube through induction
heating, with the temperature of molten alloy of 900 to
1000.degree. C., regulating the rotation speed of a copper roll to
be 3000 to 4000 r/min, and spraying the molten alloy out to the
surface of the copper roll by using the argon gas, thereby
preparing an amorphous alloy ribbon.
[0013] In another aspect of the present invention, a method for
preparing the foregoing aluminum alloy refiner described is also
provided, characterized by comprising the following steps:
[0014] (1) mixing pure metals of Zr, Cu, Al, Pd and Nb according to
a certain proportion, pre-vacuumizing a vacuum electric arc furnace
to be below 10.sup.-3Pa, charging an argon gas (preferably under a
partial pressure of 0.02 to 0.05 MPa) for smelting, and repeatedly
smelting 5 times to prepare a master alloy with even components;
and
[0015] (2) breaking the master alloy from step (1) into small
lumps, placing the small lumps into a quartz tube, prevacuumizing
the single-roll melt spinner to be below 10.sup.-3Pa, charging the
argon gas (preferably under a partial pressure of 0.05 to 0.1 MPa)
to melt the master alloy in the quartz tube through induction
heating, with the temperature of molten alloy of 900 to
1000.degree. C., regulating the rotation speed of a copper roll to
be 3000 to 4000 r/min, and spraying the molten alloy out to the
surface of the copper roll by using the argon gas, thereby
preparing an amorphous alloy ribbon.
[0016] In other aspects of the present invention, a technical
solution is also provided as follows:
[0017] In one aspect of the present invention, a method for
smelting an aluminum alloy is provided, characterized by comprising
a step of treating the aluminum alloy with a refiner, wherein the
refiner is a Zr-Cu-Al-Pd-Nb amorphous alloy, which is characterized
by comprising 40 to 60 parts of Zr, 25 to 45 parts of Cu, 1 to 15
parts of Al, 1 to 10 parts of Pd and 1 to 10 parts of Nb in terms
of mass fraction; preferably, the amorphous alloy comprises 50
parts of Zr, 35 parts of Cu, 7 parts of Al, 5 parts of Pd and 3
parts of Nb in terms of mass fraction.
[0018] In one preferable aspect of the present invention, the
Zr-Cu-Al-Pd-Nb amorphous alloy is prepared through rapid cooling;
and preferably, the rapid cooling is to melt Zr, Cu, Al, Pd and Nb
at the temperature of . and prepare the refiner by a single-roll
melt spinner.
[0019] In one preferable aspect of the present invention, the
Zr-Cu-Al-Pd-Nb amorphous alloy is prepared with a method including
the following steps:
[0020] (1) mixing pure metals of Zr, Cu, Al, Pd and Nb according to
a certain proportion, pre-vacuumizing a vacuum electric arc furnace
to be below 10.sup.-3Pa, charging an argon gas (under a partial
pressure of 0.02 to 0.05 MPa) for smelting, and repeatedly smelting
5 times to prepare a master alloy with even components; and
[0021] (2) breaking the master alloy from the step (1) into small
lumps, placing the small lumps into a quartz tube, pre-vacuumizing
a single-roll melt spinner to be below 10.sup.-3Pa, charging the
argon gas (under a partial pressure of 0.05 to 0.1 MPa) to melt the
master alloy in the quartz tube through induction heating, with the
temperature of molten alloy as 900 to 1000.degree. C., regulating
the rotation speed of a copper roll to be 3000 to 4000 r/min, and
spraying the molten alloy out to the surface of the copper roll by
using the argon gas, thereby preparing an amorphous alloy
ribbon.
[0022] In one preferable aspect of the present invention, the
Zr-Cu-Al-Pd-Nb amorphous alloy is added according to 0.15 to 0.80
wt % of the weight of the aluminum alloy to be treated during
refining treatment.
[0023] In one preferable aspect of the present invention, the
refining treatment comprises the following steps: (1) melting the
aluminum alloy to be treated at 750 to 800.degree. C. and
deslagging and degassing; and (2) adding the Zr-Cu-Al-Pd-Nb
amorphous alloy according to 0.15 to 0.80 wt % of the weight of the
aluminum alloy to be treated, holding the heat for 5 to 120 min,
and degassing.
[0024] In one preferable aspect of the present invention, the
melting temperature in the step (1) is 790.degree. C., and in the
step (2), the Zr-Cu-Al-Pd-Nb amorphous alloy is added according to
0.20 wt % of the weight of the aluminum alloy to be treated.
[0025] In one preferable aspect of the present invention, the
melting temperature in the step (1) is 790.degree. C., and in the
step (2), the Zr-Cu-Al-Pd-Nb amorphous alloy is added according to
0.60 wt % of the weight of the aluminum alloy to be treated.
[0026] In one preferable aspect of the present invention, the heat
is held for 5 to 120 min in the step (2), for example, the heat is
held for 5, 10, 30, 45 or 60 min.
[0027] In other aspects of the present invention, an aluminum alloy
prepared according to the foregoing method as described is also
provided.
[0028] In other aspects of the present invention, an application of
the foregoing aluminum alloy as described to a cast aluminum alloy
wheel is also provided.
[0029] In other aspects of the present invention, a technical
solution is provided as follows.
[0030] In one aspect of the present invention, a technological
method for modification treatment of an A356 aluminum alloy by
adding a Zr-Cu-Al-Pd-Nb amorphous ribbon intermediate alloy is
provided, characterized by comprising the following steps:
[0031] Step 1, preparing of a Zr-Cu-Al-Pd-Nb amorphous ribbon by
using a single-roll melt spinner, to be specific, preparing raw
materials according to 40% to 60% of Zr, 25% to 45% of Cu, 1% to
15% of Al, 1% to 10% of Pd and 1% to 10% of Nb in terms of atomic
percentage, smelting the raw materials in a nonconsumable electric
arc smelting furnace for smelting at first, and then placing the
smolten alloy into the single-roll melt spinner to prepare the
Zr-Cu-Al-Pd-Nb amorphous ribbon;
[0032] Step 2, smelting and refining, to be specific, with A356
aluminum alloy (chemical components of which are as shown in Table
1) as an alloy raw material and the Zr-Cu-Al-Pd-Nb amorphous ribbon
prepared in Step 1 as an intermediate alloy, placing the A356
aluminum alloy into a resistance furnace for smelting at the
smelting temperature of 750 to 800.degree. C., adding the alloy raw
material at the smelting temperature, holding the heat for 30 to 50
min till the A356 alloy raw material is completely smolten,
deslagging and stirring for 30 s, charging an Ar gas, N.sub.2 or
other inert gases for 3 to 30 min for degassing, holding the heat
for 5 to 15 min and then deslagging; adding the Zr-Cu-Al-Pd-Nb
amorphous ribbon prepared in Step 1 according to 0.2 to 0.6% of the
alloy raw material in terms of weight percentage, and holding the
heat for 5 to 120 min at 750 to 800.degree. C. ; and charging an Ar
gas, N.sub.2 or other inert gases for 3 to 30 min in a heat holding
process for degassing, deslagging and stirring for 3 to 5 min after
the heat holding is completed, and taking out a crucible to expose
in the air.
[0033] Step 3, gravity casting, to be specific, deslagging when the
temperature of molten aluminum is 700 to 750.degree. C., pouring
the molten aluminum into a cast iron mold preheated to 200.degree.
C., and performing air cooling naturally to form an aluminum alloy
rod;
[0034] Step 4, thermal treatment, to be specific, performing
thermal treatment on the aluminum alloy rod in the cast iron mold,
which comprises:
[0035] solid solution treatment, to be specific, holding the heat
for the aluminum alloy rod for 2 to 6 hours in a thermal treatment
furnace at 535.+-.5.degree. C., after heat holding, transferring
the aluminum alloy rod into hot water at 70 to 90.degree. C. within
20 seconds for quenching treatment, and taking out the rod after
maintaining the rod in the hot water for 2 to 5 min;
[0036] aging treatment, to be specific, after the quenching
treatment is completed, transferring the rod into the thermal
treatment furnace at the temperature of 130 to 160.degree. C.,
holding the heat for 3 to 12 hours, and performing air cooling.
[0037] In one aspect of the present invention, an application of
the A356 aluminum alloy, prepared according to the forgoing
technological method for modification treatment of the A356
aluminum alloy with the Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy as described, to the manufacturing of automobile
wheels is provided.
[0038] In one aspect of the present invention, a technological
method for modification treatment of an A356 aluminum alloy with a
Zr-Cu-Al-Pd-Nb amorphous ribbon intermediate alloy is provided,
which comprises the following steps: preparing a Zr-Cu-Al-Pd-Nb
amorphous ribbon by using a single-roll melt spinner; with an A356
aluminum alloy as an alloy raw material and the Zr-Cu-Al-Pd-Nb
amorphous ribbon as an intermediate alloy, adding the intermediate
alloy according to 0.2 to 0.6% of the alloy raw material in terms
of weight percentage, placing the aluminum alloy into the
resistance furnace for smelting at the smelting temperature of 750
to 800.degree. C., and holding the heat for 5 to 120 min after the
intermediate alloy is added; and performing gravity casting and
thermal treatment. Compared with the A356 aluminum alloy to which
the intermediate alloy is not added, the A356 aluminum alloy to
which the Zr-Cu-Al-Pd-Nb amorphous ribbon is added as the
intermediate alloy is refined in crystal grains, more even in the
dispersion of an eutectic silicon structure and has the mechanical
property improved to a certain extent.
[0039] With adoption of the Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy as a modifier for the A356 aluminum alloy, the
refiner provided by the present invention can favorably refine
crystal grains as well as improve the mechanical property of the
aluminum alloy to a certain extent (as shown in FIG. 3). Moreover,
the intermediate alloy improves the strength and plasticity of the
alloy, and the refined A356 aluminum alloy is very suitable for the
manufacturing of automobile wheels.
BRIEF DESCRIPTION OF DRAWINGS
[0040] In the following, embodiments of the present invention are
illustrated in detail in combination with the drawings, wherein
[0041] FIG. 1A is a diagram of an as cast metallographic structure
of an A356 aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy is added in Embodiment 1 of the present
invention.
[0042] FIG. 1B is a diagram of an as cast metallographic structure
of an A356 aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy is added in Embodiment 2 of the present
invention.
[0043] FIG. 1C is a diagram of an as cast metallographic structure
of an A356 aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy is added in Embodiment 3 of the present
invention.
[0044] FIG. 1D is a diagram of an as cast metallographic structure
of an A356 aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy is added in Embodiment 4 of the present
invention.
[0045] FIG. 1E is a diagram of an as cast metallographic structure
of an A356 aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy is added in Embodiment 5 of the present
invention.
[0046] FIG. 2A is a diagram of a metallographic structure of an
A356 aluminum alloy, in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added, at a thermal treatment state in
Embodiment 1 of the present invention.
[0047] FIG. 2B is a diagram of a metallographic structure of an
A356 aluminum alloy, in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added, at a thermal treatment state in
Embodiment 2 of the present invention.
[0048] FIG. 2C is a diagram of a metallographic structure of an
A356 aluminum alloy, in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added, at a thermal treatment state in
Embodiment 3 of the present invention.
[0049] FIG. 2D is a diagram of a metallographic structure of an
A356 aluminum alloy, in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added, at a thermal treatment state in
Embodiment 4 of the present invention.
[0050] FIG. 2E is a diagram of a metallographic structure of an
A356 aluminum alloy, in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added, at a thermal treatment state in
Embodiment 5 of the present invention.
[0051] FIG. 3A is a diagram of tensile strength of an A356 aluminum
alloy in which a Zr-Cu-Al-Pd-Nb amorphous ribbon intermediate alloy
is added in Embodiments 1 to 5 of the present invention.
[0052] FIG. 3B is a diagram of yield strength of an A356 aluminum
alloy in which a Zr-Cu-Al-Pd-Nb amorphous ribbon intermediate alloy
is added in Embodiments 1 to 5 of the present invention.
[0053] FIG. 3C is a diagram of percentage of elongation of an A356
aluminum alloy in which a Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy is added in Embodiments 1 to 5 of the present
invention.
[0054] FIG. 4A is a DSC diagram of a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon added
in the present invention.
[0055] FIG. 4B is an XRD diagram of a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon added
in the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0056] In the following, the present invention is described in
detail through embodiments, and the embodiments are provided for
the convenience of understanding instead of limiting the present
invention.
[0057] The present invention provides performing modification
treatment on an A356 aluminum alloy with a Zr-Cu-Al-Pd-Nb amorphous
ribbon as an intermediate alloy, which improves the strength and
plasticity of the alloy, and the treated A356 aluminum alloy can be
applied to the manufacturing of automobile wheels.
[0058] Embodiment 1: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0059] Step 1, preparing a Zr-Cu-Al-Pd-Nb amorphous ribbon by using
a single-roll melt spinner, to be specific, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy according to 50% of Zr, 35% of Cu, 7% of Al, 5%
of Pd and 3% of Nb in terms of atomic percentage, wherein a process
comprises the following substeps: mixing pure metals of Zr, Cu, Al,
Pd and Nb according to a certain propertion, pre-vacuumizing a
vacuum electric arc furnace to be below 10.sup.-3 Pa, charging an
argon gas (under a partial pressure of 0.02 to 0.05 MPa) for
smelting, and repeatedly smelting 5 times to prepare a master alloy
with even components; and breaking the master alloy into small
lumps, placing the small lumps into a quartz tube, pre-vacuumizing
a single-roll melt spinner to be below 10.sup.-3 Pa, charging the
argon gas (under a partial pressure of 0.05 to 0.1 MPa) to melt the
master alloy in the quartz tube through induction heating, with the
temperature of molten alloy of 900 to 1000.degree. C., regulating
the rotation speed of a copper roll to be 3000 to 4000 r/min, and
spraying the molten alloy out to the surface of the copper roll by
using the argon gas, thereby preparing an amorphous alloy ribbon.
FIG. 4 shows DSC and XRD diagrams of the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon,
indicating that the Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3
intermediate alloy of the present invention is an amorphous
alloy.
[0060] Step 2, smelting and refining, to be specific, with the A356
aluminum alloy as an alloy raw material and the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy prepared in Step 1 as the intermediate alloy,
smelting in a resistance furnace at the smelting temperature of
790.degree. C., adding the A356 aluminum alloy at the smelting
temperature, holding the heat for 35 min till the A356 alloy raw
material is completely smolten, deslagging and stirring for 30
seconds, charging an Ar gas for 3 minutes for degassing, holding
the heat for 5 min and then deslagging; adding the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy accounting for 0.2 wt % of the A356 alloy, and
holding the heat for 5 min at 790.degree. C.; and charging the Ar
gas for 5 min in the heat holding process for degassing, deslagging
and stirring for 3 to 5 min after the heat holding is completed,
and taking out a crucible to expose in the air.
[0061] Step 3, gravity casting, to be specific, deslagging when the
temperature of molten aluminum is 750.degree. C., pouring the
molten aluminum into a cast iron mold preheated to 200.degree. C.,
and performing air cooling naturally to form a rod;
[0062] Step 4, performing T6 thermal treatment on the rod in the
cast iron mold (i.e. performing aging treatment after solid
solution treatment), wherein the solid solution treatment is to
hold the heat for the rod in a thermal treatment furnace at
540.degree. C. for 2 hours, and then perform quenching treatment in
hot water at 80.degree. C.; and the aging treatment is to transfer
the rod into the thermal treatment furnace at the temperature of
150.degree. C. after the quenching treatment is completed, holding
the heat for 12 hours, and performing air cooling.
[0063] Step 5, thermal treatment, to be specific, performing
thermal treatment on the aluminum alloy rod in the cast iron mold,
which comprises the following substeps:
[0064] solid solution treatment, to be specific, holding the heat
for the aluminum alloy rod for 2 hours in a thermal treatment
furnace at 540.degree. C., after heat holding, transferring the
aluminum alloy rod into hot water at 80.degree. C. within 20
seconds for quenching treatment, and taking out the rod after
maintaining the rod in the hot water for 2 to 5 minutes; and
[0065] aging treatment, to be specific, after the quenching
treatment is completed, transferring the rod into the thermal
treatment furnace at the temperature of 150.degree. C., holding the
heat for 12 hours, and performing air cooling.
[0066] With an Olympus metallographic microscope GX51,
metallographic detection is performed on a test sample obtained
from Step 3, as shown in FIG. 1 (a), and a test sample obtained
from Step 4, as shown in FIG. 2(a); and with a WDW-20 universal
mechanics testing machine, a tensile mechanical property test is
performed on the test samples obtained from Step 4 at the tension
rate of 0.1 mm/min, as shown in FIG. 3 (a), (b) and (c).
[0067] Embodiment 2: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0068] Step 1, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy, which is the same as that in Embodiment 1;
[0069] Step 2, smelting and refining, which is different from Step
2 in Embodiment 1 only in that the heat holding time at 790.degree.
C. is changed from 5 min to 10 min after the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy is added;
[0070] Step 3, gravity casting, which is the same as that in
Embodiment 1; and
[0071] Step 4, performing T6 thermal treatment on the rod in a cast
iron mold, which is the same as that in Embodiment 1.
[0072] Metallographic detection is performed on a test sample
obtained from Step 3, as shown in FIG. 1 (b), and a test sample
obtained from Step 4, as shown in FIG. 2(b); and a tensile
mechanical property test is performed on the test samples obtained
from Step 4, as shown in FIG. 3 (a), (b) and (c).
[0073] Embodiment 3: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0074] Step 1, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy, which is the same as that in Embodiment 1;
[0075] Step 2, smelting and refining, which is different from Step
2 in Embodiment 1 only in that the heat holding time at 790.degree.
C. is changed from 5 min to 30 min after the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy is added;
[0076] Step 3, gravity casting, which is the same as that in
Embodiment 1; and
[0077] Step 4, performing T6 thermal treatment on the rod in a cast
iron mold, which is the same as that in Embodiment 1.
[0078] Metallographic detection is performed on a test sample
obtained from Step 3, as shown in FIG. 1 (c), and a test sample
obtained from Step 4, as shown in FIG. 2(c); and a tensile
mechanical property test is performed on the test samples obtained
from Step 4, as shown in FIG. 3 (a), (b) and (c).
[0079] Embodiment 4: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0080] Step 1, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy, which is the same as that in Embodiment 1;
[0081] Step 2, smelting and refining, which is different from Step
2 in Embodiment 1 only in that the heat holding time at 790.degree.
C. is changed from 5 min to 45 min after the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy is added;
[0082] Step 3, gravity casting, which is the same as that in
Embodiment 1; and
[0083] Step 4, performing T6 thermal treatment on the rod in a cast
iron mold, which is the same as that in Embodiment 1.
[0084] Metallographic detection is performed on a test sample
obtained from Step 3, as shown in FIG. 1 (d), and a test sample
obtained from Step 4, as shown in FIG. 2(d); and a tensile
mechanical property test is performed on the test samples obtained
from Step 4, as shown in FIG. 3 (a), (b) and (c).
[0085] Embodiment 5: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0086] Step 1, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy, which is the same as that in Embodiment 1;
[0087] Step 2, smelting and refining, which is different from Step
2 in Embodiment 1 only in that the heat holding time at 790.degree.
C. is changed from 10 min to 60 min after the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy is added;
[0088] Step 3, gravity casting, which is the same as that in
Embodiment 1; and
[0089] Step 4, performing T6 thermal treatment on the rod in a cast
iron mold, which is the same as that in Embodiment 1.
[0090] Metallographic detection is performed on a test sample
obtained from Step 3, as shown in FIG. 1 (e), and a test sample
obtained from Step 4, as shown in FIG. 2(e); and a tensile
mechanical property test is performed on the test samples obtained
from Step 4, as shown in FIG. 3 (a), (b) and (c).
[0091] Embodiment 6: Technological method for modification
treatment of A356 aluminum alloy with Zr-Cu-Al-Pd-Nb amorphous
ribbon intermediate alloy, comprising the following steps:
[0092] Step 1, preparing a
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy, which is the same as that in Embodiment 1;
[0093] Step 2, smelting and refining, which is different from Step
2 in Embodiment 1 only in that the weight of the
Zr.sub.50Cu.sub.35Al.sub.7Pd.sub.5Nb.sub.3 amorphous ribbon
intermediate alloy added is changed from 0.2 wt % to 0.6 wt % of
the A356 aluminum alloy;
[0094] Step 3, gravity casting, which is the same as that in
Embodiment 1; and
[0095] Step 4, performing T6 thermal treatment on the rod in a cast
iron mold, which is the same as that in Embodiment 1.
[0096] From Embodiments 1 to 6 and FIGS. 1, 2 and 3, it can be seen
that with the addition of the Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy, the .alpha.-Al phase is refined to a certain
extent, and the mechanical properties of the modified A356 are
improved to a certain extent. Based on comparison between FIG. 1
and FIG. 2, it can be seen that an eutectic silicon phase in an
eutectic structure changes from shapes of strip and clustered
sphere to a shape of approximate spheres dispersed in an a-Al
matrix after thermal treatment. Based on comparison among (a), (b),
(c), (d) and (e) in FIG. 1, it can be seen that a dendritic crystal
structure in (c), i.e. Embodiment 3, is the coarsest, with primary
dendritic crystals and secondary dendritic crystals higher than
other structures; FIG. 3 shows that both tensile strength and yield
strength of (c) are very low, but the percentage of elongation of
the material is improved, indicating that the growth of the
dendritic crystals reduces the tensile strength and yield strength
of the material but increases the plasticity of the material. The
general requirements of the automobile wheels for the mechanical
properties of the A356 aluminum alloy are as follows: the tensile
strength being Rm>220 MPa, the yield strength being Rp0.2>180
MPa, and the percentage of elongation being As>7%. Embodiments
1, 2 and 4 meet these requirements, and the mechanical properties
of the alloy subjected to 5 min heat holding in Embodiment 1 are
the best. As the heat holding time increases, the mechanical
properties undergo a phenomenon of decrease and increase in order.
However, the plasticity of the material presents the opposite
tendency, that is, as the heat holding time increases, the
plasticity increases and decreases in order, which is in conformity
with the general law that the tensile strength increases and the
plasticity decreases.
[0097] The preparation method of the present invention has the
following advantages:
[0098] (1) with adoption of a novel amorphous intermediate alloy,
the ribbon is shown as an amorphous alloy in DSC and XRD in FIG. 4
and the use of the amorphous alloy allows a more even
metallographic structure of a final product;
[0099] (2) the intermediate alloy added in a ribbon form dissolves
quickly in molten aluminum and can be distributed in an even
dispersion way after proper mechanical stirring;
[0100] (3) the A356 aluminum alloy treated with the Zr-Cu-Al-Pd-Nb
amorphous ribbon intermediate alloy have even and fine crystal
grains, with alloy elements distributing in an aluminum matrix in
an even dispersion way, which is beneficial to the improvement of
the mechanical properties of the A356 aluminum alloy;
[0101] (4) with addition of the Zr-Cu-Al-Pd-Nb amorphous ribbon
intermediate alloy, the as-cast structure subjected to 30 min heat
holding has the most and coarsest dendritic crystals; and
[0102] (5) the mechanical properties of the alloy subjected to 5
min heat holding in Embodiment 1 are the best. As the heat holding
time increases, the mechanical properties undergo a phenomenon of
decrease and increase in order. However, the plasticity of the
material presents the opposite tendency, that is, as the heat
holding time increases, the plasticity increases and decreases in
order, which is in conformity with the general law that the tensile
strength increases and the plasticity decreases.
[0103] At the same time, the inventors also prepare and test the
Zr-Cu-Al-Pd-Nb amorphous alloy comprising the following
components:
[0104] (A) 40 parts of Zr, 45 parts of Cu, 1 part of Al, 10 parts
of Pd and 1 part of Nb;
[0105] (B) 60 parts of Zr, 25 parts of Cu, 15 parts of Al, 1 part
of Pd and 10 parts of Nb;
[0106] (C) 52 parts of Zr, 29 parts of Cu, 7 parts of Al, 7 parts
of Pd and 3 part of Nb; and
[0107] (D) 57 parts of Zr, 41 parts of Cu, 12 parts of Al, 5 parts
of Pd and 1 part of Nb.
[0108] Results show that for the amorphous alloys in the groups
above under the conditions of Embodiment 1,
[0109] (1) the tensile strengths Rm of all the aluminum alloys
produced by treatment are higher than 230 MPa, with the highest Rm
value (283 MPa) of the amorphous alloy from Group (B);
[0110] (2) the yield strengths Rp0.2 of all the aluminum alloys
produced by treatment are higher than 180 MPa, with the highest Rp
value (220.1 MPa) from Group (D); and
[0111] (3) the percentages of elongation As of all the aluminum
alloys produced by treatment are higher than 7.0%, with the highest
As value (10.625%) from Group (A).
[0112] Although the present invention is illustrated through the
embodiments as described above in combination with the drawings of
the description, the embodiments above are intended only to
illustrate the experiments of the present invention in a better
way, instead of limiting the scope of implementation of the present
invention. Equivalent variations and relevant modifications made
according to the present invention or without departing from the
experimental spirit of the present invention are within the
protection scope of the invention.
* * * * *