U.S. patent application number 16/311562 was filed with the patent office on 2020-01-23 for mm'x-y metal composite functional material and preparation method thereof.
The applicant listed for this patent is Chuandong Magnetic Electronics Co., Ltd., Foshan Cheng Xian Technology Co., Ltd., University of Science and Technology Beijing. Invention is credited to KeWen LONG, Kun TAO, Hu ZHANG.
Application Number | 20200024693 16/311562 |
Document ID | / |
Family ID | 59568323 |
Filed Date | 2020-01-23 |
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United States Patent
Application |
20200024693 |
Kind Code |
A1 |
ZHANG; Hu ; et al. |
January 23, 2020 |
MM'X-Y METAL COMPOSITE FUNCTIONAL MATERIAL AND PREPARATION METHOD
THEREOF
Abstract
An MM'X--Y metal composite functional material and a preparation
method thereof; an MM'X--Y metal composite functional material,
comprising the following components in percentage by volume: A% of
M.sub.aM'.sub.bX.sub.c and B% of Y, wherein each of M and M' is any
one element of a transition group or an alloy of more than one
element, X is any one element of IIIA group or IVA group or an
alloy of more than one element, and Y is any one element of IB
group, IIB group, IIA group or IVA group, or an alloy of more than
one element, wherein the value range of a, b and c is 0.8-1.2, and
the sum of A% and B% is 100%; the material is prepared through
smelting, annealing, crushing, mixing, pressing and curing, etc.;
the mechanical performance of the MM'X--Y metal composite
functional material prepared according to the present invention is
far higher than the traditional MM'X material; the prepared MM'X--Y
metal composite functional material has an ideal magnetothermal
effect, thus can be used as a magnetic refrigeration material; the
method can prepare MM'X--Y metal composite functional materials
with any size and shape according to actual requirements; the
method is simple, and can be easily operated and realized.
Inventors: |
ZHANG; Hu; (Beijing, CN)
; TAO; Kun; (Beijing, CN) ; LONG; KeWen;
(Foshan, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Foshan Cheng Xian Technology Co., Ltd.
Chuandong Magnetic Electronics Co., Ltd.
University of Science and Technology Beijing |
Foshan
Foshan
Beijing |
|
CN
CN
CN |
|
|
Family ID: |
59568323 |
Appl. No.: |
16/311562 |
Filed: |
June 1, 2017 |
PCT Filed: |
June 1, 2017 |
PCT NO: |
PCT/CN2017/086889 |
371 Date: |
December 19, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C21D 2211/008 20130101;
B22F 2301/15 20130101; C22F 1/16 20130101; C22C 1/1036 20130101;
C22C 2202/02 20130101; C22F 1/02 20130101; B22F 9/04 20130101; C22C
30/00 20130101; B22F 2999/00 20130101; B22F 3/16 20130101; B22F
2009/044 20130101; B22F 1/0085 20130101; B22F 2998/10 20130101;
C09K 5/14 20130101; C22C 1/04 20130101; B22F 2998/10 20130101; B22F
9/04 20130101; B22F 3/18 20130101; B22F 2003/248 20130101; B22F
2998/10 20130101; B22F 9/04 20130101; B22F 3/02 20130101; B22F
2003/248 20130101; B22F 2998/10 20130101; B22F 9/04 20130101; B22F
3/20 20130101; B22F 2003/248 20130101; B22F 2998/10 20130101; B22F
9/04 20130101; B22F 3/225 20130101; B22F 2003/248 20130101; B22F
2998/10 20130101; B22F 9/04 20130101; B22F 3/105 20130101; B22F
2003/248 20130101; B22F 2999/00 20130101; B22F 3/02 20130101; B22F
3/18 20130101; B22F 3/225 20130101; B22F 3/105 20130101; B22F
2202/05 20130101 |
International
Class: |
C22C 1/10 20060101
C22C001/10; B22F 9/04 20060101 B22F009/04; B22F 3/16 20060101
B22F003/16; B22F 1/00 20060101 B22F001/00; C22F 1/16 20060101
C22F001/16; C22C 30/00 20060101 C22C030/00; C22F 1/02 20060101
C22F001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 13, 2017 |
CN |
201710238382.5 |
Claims
1. An MM'X--Y metal composite functional material, comprising the
following components in percentage by volume: A% of
M.sub.aM'.sub.bX.sub.c and B% of Y, wherein each of M and M' is any
one element of a transition group or an alloy of more than one
element, X is any one element of IIIA group or IVA group or an
alloy of more than one element, and Y is any one element of IB
group, IIB group, IIA group or IVA group, or an alloy of more than
one element, wherein the value range of a, b and c is 0.8-1.2, and
the sum of A% and B% is 100%.
2. The MM'X--Y metal composite functional material of claim 1,
wherein A% is 50%-95%, and B% is 5%-50%.
3. The MM'X--Y metal composite functional material of claim 1,
wherein A% is 60%-90%, and B% is 10%-40%.
4. A preparation method of the MM'X--Y metal composite functional
material, comprising the steps of: 1) Preparing raw materials
according to the chemical formula of M.sub.aM'.sub.bX.sub.c; 2)
Feeding the prepared raw materials into a smelting furnace,
vacuuming the furnace and cleansing the furnace by argon;
subsequently, smelting the prepared raw materials under the
protection of argon, thereby obtaining the M.sub.aM'.sub.bX.sub.c
alloy; 3) Vacuuming and annealing the M.sub.aM'.sub.bX.sub.c alloy;
4) Respectively crushing and grinding the vacuumed and annealed
M.sub.aM'.sub.bX.sub.c alloy and Y material; after screening,
obtaining powders; 5) Respectively measuring out the powder of
M.sub.aM'.sub.bX.sub.c alloy with a volume percentage of A%, and
the powder of Y material with a volume percentage of B%;
subsequently, mixing them uniformly; 6) Adopting a pressing
formation method to press the uniformly mixed powder under magnetic
field, thereby obtaining the formed material; 7) Curing the formed
material, thereby obtaining the MM'X metal composite functional
material.
5. The preparation method of the MM'X--Y metal composite functional
material of claim 4, wherein when M or M' is Mn, Mn is excessively
added according to the atomic ratio of 1%-10% for compensating its
volatile and burning losses during the preparation process, thereby
obtaining the single phase.
6. The preparation method of the MM'X--Y metal composite functional
material of claim 4, wherein when M or M' is Mn, Mn is excessively
added according to the atomic ratio of 2%-5%.
7. The preparation method of the MM'X--Y metal composite functional
material of claim 4, wherein the pressure in the smelting furnace
is controlled to be smaller than or equal to 3.times.10.sup.-3 Pa
after being vacuumed, wherein the smelting temperature is higher
than 1300.degree. C., and the smelting time is 0.5-10 minutes.
8. The preparation method of the MM'X--Y metal composite functional
material of claim 4, wherein the pressure in the smelting furnace
is 2.times.10.sup.-3-3.times.10.sup.-3 Pa after being vacuumed,
wherein the smelting temperature is 1300-1700.degree. C., and the
smelting time is 2-3 minutes.
9. The preparation method of the MM'X--Y metal composite functional
material of claim 4, wherein the vacuuming and annealing
temperature is 600-1100.degree. C., and the time is 1-30 days.
10. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the vacuuming and annealing
temperature is 700-900.degree. C., and the time is 5-15 days.
11. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the crushing method
comprises one or any combination of the following methods including
grinding, vibration grinding, rolling grinding, ball milling and
jet milling, etc., wherein the screen is a standard screen with a
mesh size greater than 10 mesh, and the particle size of the powder
is smaller than 2 mm.
12. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the screen is a standard
screen with a mesh size of 100-300 mesh, and the particle size of
the powder is 0-0.2 mm.
13. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the pressing formation is
to press the powder into a required size or shape through a rolling
method, a mold pressing method, an extrusion method, a powder
injection forming method or a discharge plasma sintering method,
wherein during the process of the pressing formation, the pressure
is 300-1500 Mpa, the temperature is 0-900.degree. C., the time is
1-240 minutes and the intensity of the magnetic field is 0-5 T.
14. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein during the process of the
pressing formation, the pressure is 600-1000 MPa, the temperature
is 0-500.degree. C., the time is 5-60 minutes and the intensity of
the magnetic field is 0-2 T.
15. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the curing temperature is
0-900.degree. C. and the curing time is 1-15 days.
16. The preparation method of the MM'X--Y metal composite
functional material of claim 4, wherein the curing temperature is
0-500.degree. C. and the curing time is 2-7 days.
Description
TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to the technical field of
metal materials, and more particularly, to an MM'X--Y (M and M' are
transitional elements, and X is an element of IIIA group or IVA
group) metal composite functional material and a preparation method
thereof.
BACKGROUND OF THE INVENTION
[0002] Martensitic phase transition is an important diffusionless
solid-state phase transition of crystal structure, and is a
first-order transition. Martensite is formed in carbon steels by
the rapid cooling of the austenite form of iron at such a high rate
that carbon atoms do not have time to diffuse out of the crystal
structure in large enough quantities to form cementite. The
martensitic reaction begins during cooling when the austenite
reaches the martensite start temperature and the parent austenite
becomes mechanically unstable. As a result of the cooling, the
face-centered cubic austenite transforms to a highly strained
body-centered tetragonal form called martensite that is
supersaturated with carbon. The shear deformations that result
produce a large number of dislocations, which is a primary
strengthening mechanism of steels. During this process, an
increasingly large percentage of the austenite transforms to
martensite until the lower phase transition temperature is reached,
at which time the transition is completed. Martensitic transition
materials are widely used for strengthening steels, toughening
materials, reducing quenching deformations, improving shape-memory
effect and enhancing super-elasticity. They're ideal functional
materials.
[0003] For the huge structural difference between the martensitic
phase and the parent phase, the martensitic transition process is
usually accompanied with a drastic change of crystal structure. The
aforesaid effect is also applied for shape-memory alloys. Namely,
the material with a certain shape is cooled at a high temperature
higher than the martensitic transition temperature (T.sub.M),
thereby forming a low-temperature martensitic phase. In this state,
the material deforms under load. After being heated to the
martensitic reverse transition temperature (T.sub.A), it is
restored to the original shape. It's difficult to improve the
response frequency and sensitivity of traditional shape-memory
alloys because their deformations are controlled by temperature and
stress variation.
[0004] In recent years, researches have shown that the martensitic
transition of some materials can be controlled by a magnetic field
other than a temperature field and a stress field. These novel
materials with ferromagnetic and thermo-elastic martensitic
transition are called ferromagnetic martensitic transition alloys.
Due to the coupling effect of the magnetic transition and the
structural transition, the structure, the magnetic properties and
the electric properties of the crystal are changed violently. As a
result, the ferromagnetic shape-memory alloys present various
functional effects such as shape-memory effect, magnetostriction
effect, magneto-resistance effect, Hall effect and magneto-thermal
effect, etc. These rich magnetic properties and potential
application values make the ferromagnetic martensitic transition
alloys become novel functional materials that attract wide
attentions.
[0005] Presently, the largest family of the ferromagnetic
martensitic transition alloys is the Heusler alloys, including
Ni--Mn--Ga, Ni--Mn--Al, Ni--Mn--In and Ni--Mn--Sn. More recently, a
novel MM'X (M and M' are transitional elements, and X is an element
of IIIA group or IVA group) ferromagnetic martensitic transition
material (e.g., MnCoGe or MnNiGe) has been found by researchers.
Through adjusting the compositions and preparing processes, the
MM'X alloy also shows a magnetic-field-induced ferromagnetic
martensitic transition. During the transition, a huge deformation
of crystal structure and a magneto-thermal effect are achieved, and
the phase transition temperature can be adjusted within a wide
range. Thus, the MM'X alloy can be used as a multifunctional
material (e.g., shape-memory material, negative expansion material
and magnetic refrigeration material, etc.), and is considered as a
new generation of ferromagnetic martensitic transition functional
materials.
[0006] However, the huge deformation of crystal structure of the
MM'X functional material during the martensitic transition process
generates a large internal stress, making the MM'X functional
material broken after the transition. Thus, the difficulty of
forming and mechanical machining is sharply increased, and the
application range of the material is greatly limited. Moreover, the
research on how to improve the mechanical performance of the MM'X
functional material has not been reported until now.
[0007] In conclusion, it's urgent for those skilled in this field
to develop a novel MM'Y functional material with good mechanical
properties.
SUMMARY OF THE INVENTION
[0008] The purpose of the present invention is to solve the
shortcomings in the prior art by providing an MM'X--Y metal
composite functional material and a preparation method thereof.
According to the method of the present invention, an MM'X--Y metal
composite functional material with an excellent mechanical
performance and ferromagnetic martensitic transition can be
prepared. The prepared material possesses a high magnetic
refrigeration performance and a wide application range.
[0009] To achieve the above purpose, the present invention adopts
the following technical solution:
[0010] An MM'X--Y metal composite functional material, comprising
the following components in percentage by volume:
[0011] A% of M.sub.aM'.sub.bX.sub.c and B% of Y, wherein each of M
and M' is any one element of a transition group or an alloy of more
than one element, X is any one element of IIIA group or IVA group
or an alloy of more than one element, and Y is any one element of
IB group, IIB group, IIA group or IVA group, or an alloy of more
than one element, wherein the value range of a, b and c is 0.8-1.2,
and the sum of A% and B% is 100%.
[0012] In another aspect of the present invention, A% is 50%-95%,
and B% is 5%-50%.
[0013] In another aspect of the present invention, A% is 60%-90%,
and B% is 10%-40%.
[0014] A preparation method of the MM'X--Y metal composite
functional material, comprising the steps of: [0015] 1) Preparing
raw materials according to the chemical formula of
M.sub.aM'.sub.bX.sub.c; [0016] 2) Feeding the prepared raw
materials into a smelting furnace, vacuuming the furnace and
cleansing the furnace by argon; subsequently, smelting the prepared
raw materials under the protection of argon, thereby obtaining the
M.sub.aM'.sub.bX.sub.c alloy; [0017] 3) Vacuuming and annealing the
M.sub.aM'.sub.bX.sub.c alloy; [0018] 4) Respectively crushing and
grinding the vacuumed and annealed M.sub.aM'.sub.bX.sub.c alloy and
Y material; after screening, obtaining powders; [0019] 5)
Respectively measuring out the powder of M.sub.aM'.sub.bX.sub.c
alloy with a volume percentage of A%, and the powder of Y material
with a volume percentage of B%; subsequently, mixing them
uniformly; [0020] 6) Adopting a pressing formation method to press
the uniformly mixed powder under magnetic field, thereby obtaining
the formed material; [0021] 7) Curing the formed material, thereby
obtaining the MM'X metal composite functional material.
[0022] In another aspect of the present invention, when M or M' is
Mn, Mn is excessively added according to the atomic ratio of 1%-10%
for compensating its volatile and burning losses during the
preparation process, thereby obtaining the single phase.
[0023] In another aspect of the present invention, when M or M' is
Mn, Mn is excessively added according to the atomic ratio of
2%-5%.
[0024] In another aspect of the present invention, the pressure in
the smelting furnace is controlled to be smaller than or equal to
3.times.10.sup.-3 Pa after being vacuumed. The smelting temperature
is higher than 1300.degree. C., and the smelting time is 0.5-10
minutes.
[0025] In another aspect of the present invention, the pressure in
the smelting furnace is 2.times.10.sup.-3-10.sup.-3 Pa after being
vacuumed. The smelting temperature is 1300-1700.degree. C., and the
smelting time is 2-3 minutes.
[0026] In another aspect of the present invention, the vacuuming
and annealing temperature is 600-1100.degree. C., and the time is
1-30 days.
[0027] In another aspect of the present invention, the vacuuming
and annealing temperature is 700-900.degree. C., and the time is
5-15 days.
[0028] In another aspect of the present invention, the crushing
method comprises one or any combination of the following methods
including grinding, vibration grinding, rolling grinding, ball
milling and jet milling, etc. The screen is a standard screen with
a mesh size greater than 10 mesh, and the particle size of the
powder is smaller than 2 mm.
[0029] In another aspect of the present invention, the screen is a
standard screen with a mesh size of 100-300 mesh, and the particle
size of the powder is 0-0.2 mm.
[0030] In another aspect of the present invention, the pressing
formation is to press the powder into a required size or shape
through a rolling method, a mold pressing method, an extrusion
method, a powder injection forming method or a discharge plasma
sintering method. During the process of the pressing formation, the
pressure is 300-1500 Mpa, the temperature is 0-900.degree. C., the
time is 1-240 minutes and the intensity of the magnetic field is
0-5 T.
[0031] In another aspect of the present invention, during the
process of the pressing formation, the pressure is 600-1000 MPa,
the temperature is 0-500.degree. C., the time is 5-60 minutes and
the intensity of the magnetic field is 0-2 T.
[0032] In another aspect of the present invention, the curing
temperature is 0-900.degree. C. and the curing time is 1-15
days.
[0033] In another aspect of the present invention, the curing
temperature is 0-500.degree. C. and the curing time is 2-7
days.
[0034] Compared with the prior art, the present invention has the
following advantages:
[0035] First, the present invention provides a novel MM'X--Y metal
composite functional material; second, the mechanical performance
of the MM'X--Y metal composite functional material prepared
according to the present invention is far higher than the
traditional MM'X material; third, the prepared MM'X--Y metal
composite functional material has an ideal magnetothermal effect,
thus can be used as a magnetic refrigeration material; fourth, the
preparation method of the present invention can prepare MM'X--Y
metal composite functional materials with any size and shape
according to actual requirements; fifth, the preparation method of
the present invention is simple, and can be easily operated and
realized in industrial production.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] To clearly expound the technical solution of the present
invention, the drawings and embodiments are hereinafter combined to
illustrate the present invention. Obviously, the drawings are
merely some embodiments of the present invention and those skilled
in the art can associate themselves with other drawings without
paying creative labor.
[0037] FIG. 1 is a topography diagram of the smelted
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 prepared according to
embodiment 1 of the present invention;
[0038] FIG. 2 is a topography diagram of the smelted 70%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In metal composite
functional material prepared according to embodiment 1 of the
present invention;
[0039] FIG. 3 is a stress-strain curve graph of the 70%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In metal composite
functional material prepared according to embodiment 1 of the
present invention;
[0040] FIG. 4 is a diagram showing the temperature dependence of
.DELTA.S of the 70% Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30%
In metal composite functional material prepared according to
embodiment 1 of the present invention in different magnetic
fields;
[0041] FIG. 5 is a stress-strain curve graph of the 75%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In metal composite
functional material prepared according to embodiment 2 of the
present invention;
[0042] FIG. 6 is a stress-strain curve graph of the 80%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In metal composite
functional material prepared according to embodiment 3 of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0043] Drawings and detailed embodiments are combined hereinafter
to elaborate the technical principles of the present invention.
Embodiment 1
[0044] As shown in FIGS. 1-4, the present invention discloses a 70%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In metal composite
functional material and a preparation method thereof.
[0045] The preparation method of the 70%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In metal composite
functional material, comprising the steps of: [0046] 1) Preparing
raw materials according to the chemical formula of
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5, wherein the raw
materials are commercially available metals including Mn, Fe, Ni,
Si and Ge with a purity higher than 99.9 wt. %, and Mn is
excessively added according to the atomic ratio of 5% for
compensating its volatile and burning losses during the preparation
process; [0047] 2) Adopting an electric arc smelting method;
feeding the prepared raw materials into a smelting furnace,
vacuuming the smelting furnace until the pressure intensity reaches
2.times.10.sup.-3 Pa, and cleansing the furnace by argon;
subsequently, smelting the prepared raw materials at a temperature
of 1500.degree. C. for 3 minutes under the protection of argon,
thereby obtaining the cast ingot
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5; [0048] 3) Placing the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 into a quartz tube with
a vacuum degree of 5.times.10.sup.-3 Pa, and annealing at a
temperature of 850.degree. C. for 7 days; [0049] 4) Respectively
crushing and grinding the vacuumed and annealed
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 and metal In by using an
agate mortar, and screening out the irregular powder with a size
smaller than 0.1 mm according to the screening standard of
150-mesh; [0050] 5) Respectively measuring out the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 powder with a volume
percentage of 70%, and the In powder with a volume percentage of
30%; subsequently, mixing them uniformly; [0051] 6) Pressing the
uniformly mixed powder at the condition of 150.degree. C. and 900
MPa for 5 minutes under zero magnetic field, thereby obtaining a
cylindrical 70% Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In
metal composite functional material with a diameter of 10 mm;
[0052] 7) Curing at a temperature of 150.degree. C. for 7 days,
thereby obtaining the 70%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+30% In metal composite
functional material, namely, the product of this embodiment.
[0053] The morphology of the smelted
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 sample prepared in
embodiment 1 is shown in FIG. 1. As can be seen from FIG. 1, after
a traditional smelting process, the sample undergoes a martensitic
transition when being cooled from a high temperature to a room
temperature. The sample is crumbled due to the huge internal stress
generated in the transition process, making the forming and
mechanical machining become extremely difficult. The application
range of the functional material is thus greatly limited. The
morphology of the product of embodiment 1 is shown in FIG. 2. As
can be seen, it can be easily formed and processed, effectively
solving the prior technical problems.
[0054] For the mechanical performance of the traditional crumbled
MM'X alloy is extremely poor, the stress-strain curve test cannot
be carried out. In contrast, the mechanical performance of the
product prepared in embodiment 1 is remarkably improved so that the
test can be easily performed. The stress-strain curve of the
prepared product can be tested by using a WDW200D type
microcomputer control universal material tester. As shown in FIG.
3, after being tested, the compressive strength of the prepared
product is 45 MPa, and the corresponding strain is 9.2%.
[0055] After measuring the isothermal magnetization curve (M-H
curve) of the prepared product by using a magnetic measurement
system (Versalab Free Measurement System developed by Quantum
Design, Inc.), the magnetic entropy change .DELTA.S can be
calculated from the isothermal magnetization curve according to
Maxwell's relation
.DELTA.S=.intg..sub.0.sup.H(.differential.M/.differential.T).sub.HdH
. FIG. 4 shows the temperature dependence of .DELTA.S of the
prepared product in different magnetic fields. As can be seen, when
the transition temperature is near 311K, the maximum value of the
magnetic entropy change appears. When the intensity of the magnetic
field respectively varies from 0 to 1 T, 0 to 2 T, and 0 to 3 T,
the maximum magnetic entropy change of the sample is respectively
4.5 J/kgK, 9.9 J/kgK, and 15.3 J/kgK. Presently, a magnetic field
at intensity of 2 T can be obtained by utilizing the permanent
magnet NdFeB. Therefore, the magnetic entropy changes of the
material when the magnetic intensity varies from 0 to 2 T attracts
more attentions. Under such a circumstance, the maximum value of
the magnetic entropy change (9.9 J/kgK) of the prepared product is
much greater than that (when the magnetic intensity is 2 T, the
magnetic entropy change is 5.0 J/kgK) of the traditional
room-temperature magnetic refrigeration material Gd. It means that
the product of the aforesaid embodiment can be used as a better
room-temperature functional material.
Embodiment 2
[0056] As shown in FIG. 5, the present invention discloses a 75%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In metal composite
functional material and a preparation method thereof. The
preparation method of the 75%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In metal composite
functional material, comprising the steps of: [0057] 1) Preparing
raw materials according to the chemical formula of
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5, wherein the raw
materials are commercially available metals including Mn, Fe, Ni,
Si and Ge with a purity higher than 99.9 wt. %, and Mn is
excessively added according to the atomic ratio of 5% for
compensating its volatile and burning losses during the preparation
process; [0058] 2) Adopting an electric arc smelting method;
feeding the prepared raw materials into a smelting furnace,
vacuuming the smelting furnace until the pressure intensity reaches
2.5.times.10.sup.-3 Pa, and cleansing the furnace by argon;
subsequently, smelting the prepared raw materials at a temperature
of 1700.degree. C. for 2 minutes under the protection of argon,
thereby obtaining the cast ingot
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5; [0059] 3) Placing the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 into a quartz tube with
a vacuum degree of 5.times.10.sup.-3 Pa, and annealing at a
temperature of 850.degree. C. for 8 days; [0060] 4) Respectively
crushing and grinding the vacuumed and annealed
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 and metal In by using an
agate mortar, and screening out the irregular powder with a size
smaller than 0.07 mm according to the screening standard of
200-mesh; [0061] 5) Respectively measuring out the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 powder with a volume
percentage of 75%, and the In powder with a volume percentage of
25%; subsequently, mixing them uniformly; [0062] 6) Pressing the
uniformly mixed powder at the condition of 140.degree. C. and 900
MPa for 10 minutes under zero magnetic field, thereby obtaining a
cylindrical 75% Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In
metal composite functional material with a diameter of 10 mm;
[0063] 7) Curing at a temperature of 500.degree. C. for 7 days,
thereby obtaining the 75%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In metal composite
functional material.
[0064] The stress-strain curve of the 75%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+25% In metal composite
material can be tested by using a WDW200D type microcomputer
control universal material tester. As shown in FIG. 5, after being
tested, the compressive strength of the prepared product is 48 MPa,
and the corresponding strain is 15.6%. Meanwhile, the magnetic test
shows that the magnetothermal effect of the prepared product of
embodiment 2 is better than that of the traditional
room-temperature magnetic refrigeration material Gd.
Embodiment 3
[0065] As shown in FIG. 6, the present invention discloses an 80%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In metal composite
functional material and a preparation method thereof. The
preparation method of the 80%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In metal composite
functional material, comprising the steps of: [0066] 1) Preparing
raw materials according to the chemical formula of
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5, wherein the raw
materials are commercially available metals including Mn, Fe, Ni,
Si and Ge with a purity higher than 99.9 wt. %, and Mn is
excessively added according to the atomic ratio of 3% for
compensating its volatile and burning losses during the preparation
process; [0067] 2) Adopting an electric arc smelting method;
feeding the prepared raw materials into a smelting furnace,
vacuuming the smelting furnace until the pressure intensity reaches
3.times.10.sup.-3 Pa, and cleansing the furnace by argon;
subsequently, smelting the prepared raw materials at a temperature
of 1700.degree. C. for 2 minutes under the protection of argon,
thereby obtaining the cast ingot
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5; [0068] 3) Placing the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 into a quartz tube with
a vacuum degree of 5.times.10.sup.-3 Pa, and annealing at a
temperature of 750.degree. C. for 15 days; [0069] 4) Respectively
crushing and grinding the vacuumed and annealed
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5 and metal In by using an
agate mortar, and screening out the irregular powder with a size
smaller than 0.1 mm according to the screening standard of
150-mesh; [0070] 5) Respectively measuring out the
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0. 5 powder with a volume
percentage of 80%, and the In powder with a volume percentage of
20%; subsequently, mixing them uniformly; [0071] 6) Pressing the
uniformly mixed powder at the condition of 140.degree. C. and 900
MPa for 6 minutes in zero magnetic field, thereby obtaining a
cylindrical 80% Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In
metal composite functional material with a diameter of 10 mm;
[0072] 7) Curing at a temperature of 500.degree. C. for 7 days,
thereby obtaining the 80%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In metal composite
functional material.
[0073] The stress-strain curve of the 80%
Mn.sub.0.6Fe.sub.0.4NiSi.sub.0.5Ge.sub.0.5+20% In metal composite
material can be tested by using a WDW200D type microcomputer
control universal material tester. As shown in FIG. 6, after being
tested, the compressive strength of the prepared product is 41 MPa,
and the corresponding strain is 14.9%.
Embodiment 4
[0074] The present invention discloses a 60%
MnCoCu.sub.0.08Ge.sub.0.92+40% Sn metal composite functional
material and a preparation method thereof. The preparation method
of the 60% MnCoCu.sub.0.08Ge.sub.0.92+40% Sn metal composite
functional material, comprising the steps of: [0075] 1) Preparing
raw materials according to the chemical formula of
MnCoCu.sub.0.08Ge.sub.0.92, wherein the raw materials are
commercially available metals including Mn, Co, Cu and Ge with a
purity higher than 99.9 wt. %, and Mn is excessively added
according to the atomic ratio of 3% for compensating its volatile
and burning losses during the preparation process; [0076] 2)
Adopting an electric arc smelting method; feeding the prepared raw
materials into a smelting furnace, vacuuming the smelting furnace
until the pressure intensity reaches 2.times.10.sup.-3 Pa, and
cleansing the furnace by argon; subsequently, smelting the prepared
raw materials at a temperature of 1600.degree. C. for 3 minutes
under the protection of argon, thereby obtaining the cast ingot
MnCoCu.sub.0.8Ge.sub.0.92; [0077] 3) Placing the
MnCoCu.sub.0.08Ge.sub.0.92 into a quartz tube with a vacuum degree
of 5.times.10.sup.-3 Pa, and annealing at a temperature of
800.degree. C. for 15 days; [0078] 4) Respectively crushing and
grinding the vacuumed and annealed MnCoCu.sub.0.08Ge.sub.0.92 and
metal Sn by using a jet mill, and screening out the irregular
powder with a size smaller than 0.05 mm according to the screening
standard of 300-mesh; [0079] 5) Respectively measuring out the
MnCoCu.sub.0.08Ge.sub.0.92 powder with a volume percentage of 60%,
and the Sn powder with a volume percentage of 40%; subsequently,
mixing them uniformly; [0080] 6) Pressing the uniformly mixed
powder at the condition of room temperature and 960 MPa for 15
minutes in a magnetic field at intensity of 1.5 T, thereby
obtaining a cylindrical 60% MnCoCu.sub.0.08Ge.sub.0.92+40% Sn metal
composite functional material with a diameter of 10 mm; [0081] 7)
Curing at a temperature of 500.degree. C. for 7 days, thereby
obtaining the 60% MnCoCu.sub.0.08Ge.sub.0.92+40% Sn metal composite
functional material, namely, the product of this embodiment.
Embodiment 5
[0082] The present invention discloses a 75%
Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1+25% InSn metal composite
functional material and a preparation method thereof. The
preparation method of the 75% Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1+25%
InSn metal composite functional material, comprising the steps of:
[0083] 1) Preparing raw materials according to the chemical formula
of Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1, wherein the raw materials are
commercially available metals including Mn, Go, Ge and Si with a
purity higher than 99.9 wt. %, and Mn is excessively added
according to the atomic ratio of 4% for compensating its volatile
and burning losses during the preparation process; [0084] 2)
Adopting an electric arc smelting method; feeding the prepared raw
materials into a smelting furnace, vacuuming the smelting furnace
until the pressure intensity reaches 3.times.10.sup.-3 Pa, and
cleansing the furnace by argon; subsequently, smelting the prepared
raw materials at a temperature of 1400.degree. C. for 3 minutes
under the protection of argon, thereby obtaining the cast ingot
Mn.sub.0.95COGe.sub.0.9Si.sub.0.1; [0085] 3) Placing the
Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1 into a quartz tube with a vacuum
degree of 5.times.10.sup.-3 Pa, and annealing at a temperature of
900.degree. C. for 5 days; [0086] 4) Respectively crushing and
grinding the vacuumed and annealed
Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1 and metal InSn by using a high
energy ball mill, and screening out the irregular powder with a
size smaller than 0.06 mm according to the screening standard of
250-mesh; [0087] 5) Respectively measuring out the
Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1 powder with a volume percentage
of 75%, and the InSn powder with a volume percentage of 25%;
subsequently, mixing them uniformly; [0088] 6) Pressing the
uniformly mixed powder at the condition of 800.degree. C. and 600
MPa for 15 minutes in zero magnetic field, thereby obtaining a
cylindrical 75% Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1+25% InSn metal
composite functional material with a diameter of 10 mm; [0089] 7)
Curing at a temperature of 500.degree. C. for 7 days, thereby
obtaining the 75% Mn.sub.0.95CoGe.sub.0.9Si.sub.0.1+25% InSn metal
composite functional material, namely, the product of this
embodiment.
[0090] The description of above embodiments allows those skilled in
the art to realize or use the present invention. Without departing
from the spirit and essence of the present invention, those skilled
in the art can combine, change or modify correspondingly according
to the present invention. Therefore, the protective range of the
present invention should not be limited to the embodiments above
but conform to the widest protective range which is consistent with
the principles and innovative characteristics of the present
invention. Although some special terms are used in the description
of the present invention, the scope of the invention should not
necessarily be limited by this description. The scope of the
present invention is defined by the claims.
* * * * *