CN107545971A - A kind of preparation method of permanent magnetism healing accelerating dressing - Google Patents
A kind of preparation method of permanent magnetism healing accelerating dressing Download PDFInfo
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- CN107545971A CN107545971A CN201710727037.8A CN201710727037A CN107545971A CN 107545971 A CN107545971 A CN 107545971A CN 201710727037 A CN201710727037 A CN 201710727037A CN 107545971 A CN107545971 A CN 107545971A
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Abstract
The present invention relates to a kind of permanent magnetism healing accelerating dressing and preparation method thereof, and NdFeB magnetic powder and graphene powder are mixed, be orientated in magnetic field and be pressed into blank by permanent magnetism healing accelerating dressing, then are sintered heat treatment, obtain permanent-magnet material；Finally permanent-magnet material is attached permanent magnetism healing accelerating dressing is made on a carrier layer.Beneficial effects of the present invention are：The present invention permanent magnetism healing accelerating dressing, have promote wound healing, reduce scar formed, anti-inflammatory analgesic the effect of, it is quick and without often change.Permanent-magnet material crystal grain therein is tiny, uniform, mechanical property and coercivity are obviously improved.
Description
Technical field
The invention belongs to processing technique field, and in particular to it is a kind of containing rare earth neodymium, iron, boron material permanent magnetism healing accelerating dressing system
Preparation Method.
Background technology
Traditional sintered Nd-Fe-B magnetic material belongs to typical sintered metal product, and compression strength is small, fragility is big, Yi Cong
Grain boundaries trigger grain boundary fracture, and with the continuous extension of Sintered NdFeB magnet application field, magnet will unavoidably be subjected to rushing
The test of adverse circumstances such as hit, vibrate, magnet will bring massive losses once rupturing to user.Therefore must be to sintering neodymium iron
Boron magnet mechanical property is furtherd investigate, optimized production process, improves the mechanical properties such as compression strength, the toughness of magnet, is reduced
Breakage and the danger that is broken in use environment in blank subsequent processes.
The content of the invention
The main technical performance index of neodymium-iron-boron magnetic material is that coercivity H (including rectify by HCJ Hcj and magnetic strength
Stupid power Hcb), remanent magnetism Br, magnetic energy product (BH) max and Curie temperature Tc.The researcher of neodymium-iron-boron magnetic material is mainly maximum
The potentiality of material are developed to limit, improve the coercivity H of permanent-magnet material, remanent magnetism Br, magnetic energy product (BH) max and Curie temperature Tc.
Wherein coercivity is the ability that magnet keeps permanent magnetism, required reverse when typically dropping to zero with the magnetically saturated magnetic induction intensity of material
Magnetic field intensity is measured.Coercitive improvement can improve the temperature stability of NdFeB material, therefore improve Neodymium iron boron magnetic material
The coercivity of material, which turns into, improves the most important ring of NdFeB material performance.
In order to solve the above problems, the invention provides a kind of preparation method of permanent magnetism healing accelerating dressing, permanent magnetism of the invention speed
More tiny crystal grain, uniform, mechanical property and coercivity is pasted to be obviously improved.
It is an object of the invention to provide a kind of preparation method of permanent magnetism healing accelerating dressing.
According to the permanent magnetism healing accelerating dressing of the embodiment of the present invention, a kind of system of permanent magnetism healing accelerating dressing of permanent magnetism healing accelerating dressing
Preparation Method, it is characterised in that comprise the following steps：
(1) NdFeB magnetic powder and graphene powder are mixed and is configured to mixed powder, the graphene powder
Content is the 0.03-0.20wt% of the mixed powder；
(2) mixed powder obtained in step (1) is orientated in magnetic field and is pressed into blank；
(3) heat treatment is sintered to the blank obtained in step (2), obtains permanent-magnet material；
(4) permanent-magnet material obtained in step (3) is attached and permanent magnetism healing accelerating dressing is made on a carrier layer.
Because graphene is a kind of flat film for the individual layer laminated structure being made up of carbon atom with sp＆sup2 hybridized orbits
Material, its thickness of thin, intensity are big, and in the present invention, the mixed powder sintering that graphene powder is configured with NdFeB magnetic powder is made
NdFeB material, during sintering prepares NdFeB material, graphene is placed in Nd-Fe-B alloy grain boundaries as doping item,
The movement of crystal boundary is hindered, prevents the aggregation and growth of crystal grain, crystal grain is tiny, uniform NdFeB material so as to obtain.Moreover, by
It is non-magnetic phase dopant in graphene, domain wall drift during to magnetic reversal can play nail letter effect, can effectively hinder domain wall
It is mobile, so as to improve the performances such as the coercivity of sintered Nd-Fe-B permanent magnetic material, improve the stability of neodymium-iron-boron magnetic material.Separately
Outside, graphene itself intensity superelevation, thus with the addition of the compression strength of neodymium-iron-boron magnetic material prepared by micro graphene with
Toughness also has corresponding raising.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, in step (1), the neodymium
The composition of iron boron magnetic powder is RwQxMyNz, wherein, R, Q, M, N representative element species, R Pr, Nd, Dy, Tb, Ho and/or Gd；Q
For Fe and/or Co；M is B element；N is Al, Nb, Zr, Cu, Ga, Mo, W and/or V；29≤w≤33；60≤x≤ 69；0.98
≤y≤1.2；0≤z≤3；W+x+y+z=100.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, it is described mixed in step (1)
It is 300-2500ppm to close carbon content in powder.
Technique according to the invention scheme, carbon element content can produce unfavorable shadow to the magnetic property of neodymium-iron-boron magnetic material
Ring.So should to the NdFeB magnetic powder of selection in carbon content carry out strictly limitation (carbon content is in general control mixed powder
300-2500ppm) so that after later stage graphene adds, the carbon content for sintering the Nd-Fe-B permanent magnetic material of preparation maintains one
In fixed scope, i.e., carbon content ensures neodymium-iron-boron magnetic material in the range of 300-2500ppm in obtained permanent-magnet material
Magnetic behavior.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, it is described in step (1)
The particle diameter of NdFeB magnetic powder is 2-10um.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, in step (1), the stone
The thickness of black alkene powder is 3-5nm, a diameter of 50-1000nm of the graphene powder.The thickness of graphene powder is graphite
The height of alkene powder；The maximum gauge of the cross section of a diameter of graphene powder of graphene powder.
The solution of the present invention is being analysed in depth to obtain, the neodymium-iron-boron magnetic material that addition graphene powder is produced
Performance raising amount and the particle size of selected NdFeB magnetic powder and graphene powder are closely related.Therefore the present invention is by right
The neodymium-iron-boron magnetic material performance that the NdFeB magnetic powder and graphene powder of a large amount of different-grain diameter sizes are prepared carry out analysis and
Optimization, the NdFeB magnetic powder and thickness that preferably selection particle diameter is 2-10um are 3-5nm, a diameter of 50-1000nm Graphene powder
Produce neodymium-iron-boron magnetic material in end so that the magnetic behavior of NdFeB material is farthest enhanced.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, in step (1), the neodymium
Iron boron magnetic powder is mixed with the graphene powder under the protection of inert gas.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, the inert gas is nitrogen
Gas.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, in step (1), neodymium iron boron
The primary flour that the Nd Fe B alloys slab that it is 0.2-10mm by thickness that magnetic, which is, is below 10mm into particle diameter through hydrogen break process,
Then primary flour is obtained through Gas grinding.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, in step (2), by described in
Mixed powder is orientated and preliminary compressing in more than 1.2T magnetic field, is then carried out isostatic pressed processing again and is pressed into blank.
Technique according to the invention scheme, isostatic pressing technology be it is a kind of using product in closed pressure vessel each to equalization
Ultra high pressure state under the ultrahigh-pressure hydraulic sophisticated equipment that is molded, be at normal temperatures, generally to make jacket with rubber or plastics
Mold materials, it is mainly used in powder body material shaping by pressure medium of liquid, for further sintering, forging or high temperature insostatic pressing (HIP) process
Base substrate is provided.It is 100~630MPa typically using pressure.Isostatic pressing technology is widely used to ceramic casting, atomic energy, instrument
Prepared by manufacture, plastics, super high pressure food sterilizing and graphite, ceramics, permanent magnet, high-voltage electromagnetic porcelain vase, bio-pharmaceutical, food is protected
The fields such as fresh, high performance material, military project.
Wherein Nd Fe B alloys slab can by by various simple metal Nd, Pr, Dy, Al, Ga, Co, Fe and alloy B-Fe,
Nb-Fe etc. by component design requirement with taking raw material, in vacuum induction slab stove melting obtain, pass through entering for process above condition
One step, which controls, make it that the performance of neodymium-iron-boron magnetic material producing to obtain is more excellent.
Hydrogen is broken for a kind of alloy powder preparation method, its mechanism for using alloy during inhaling hydrogen and putting hydrogen institute itself
Caused grain boundary fracture and transgranular fracture cause alloy pulverization, so as to obtain the alloy powder of certain particle size.
According to the preparation method of the permanent magnetism healing accelerating dressing of the embodiment of the present invention, wherein, it is described in step (3)
Sintering heat treatment sinters 1-4 hours for the blank is placed in vacuum sintering furnace, at 1000-1300 DEG C；Then in 800-
1-4 hours are tempered at 1000 DEG C；1-4 hours are tempered again at 400-600 DEG C.
Beneficial effects of the present invention are：The permanent magnetism healing accelerating dressing of the present invention, permanent magnetism healing accelerating dressing of the invention, which has, promotes wound
Healing, reduce scar formed, anti-inflammatory analgesic the effect of, it is quick and without often change.
(1) permanent-magnet material therein with the addition of graphene powder, and its finished product crystal grain is tiny, uniform, mechanical property and coercive
Power is obviously improved.
(2) carbon content in the range of 300-2500ppm, ensures the magnetic of permanent-magnet material in permanent-magnet material produced by the present invention
Performance.
(3) particle diameter of the invention by limiting NdFeB magnetic powder and graphene powder, the particle diameter of NdFeB magnetic powder is 2-
10um, the thickness of graphene powder is 3-5nm, a diameter of 50-1000nm, significantly improves the magnetic property of permanent-magnet material material.
Embodiment
To make the object, technical solutions and advantages of the present invention clearer, technical scheme will be carried out below
Detailed description.Obviously, described embodiment is only part of the embodiment of the present invention, rather than whole embodiments.Base
Embodiment in the present invention, those of ordinary skill in the art are resulting on the premise of creative work is not made to be owned
Other embodiment, belong to the scope that the present invention is protected.
Embodiment 1
The preparation method of permanent magnetism healing accelerating dressing, comprises the following steps：
(1) model 42SH magnetic materials are selected, its group is grouped into：
Nd27.8Fe65.68B1.02Dy4.2Al0.2Co1.0Cu0.1, by component design with raw material is taken, then by raw material in vacuum induction slab stove
In be smelted into slab, the average thickness of slab is 0.3-0.45mm；
(2) the Nd-Fe-B alloy casting pieces obtained in step (1) are positioned over progress hydrogen decrepitation processing in hydrogen crushing furnace,
Obtain primary flour of the granularity within 10mm；
(3) the primary flour obtained in step (2) is milled to particle diameter range in 3-5 μm through air-flow grinding process
NdFeB magnetic powder, for example, particle diameter is respectively 3 μm, 4 μm, 5 μm, 0.03wt% graphene powders are added under nitrogen protection
(thickness 3-5nm, a diameter of 50-1000nm) is well mixed through blending processes of powders, controls the carbon content in mixed powder in 400-
Between 1000ppm.
(4) by the mixed powder obtained in step (3) in 1.8T magnetic fields it is vertical orientated compressing, then through isostatic pressed
Technique is pressed into base；
(5) blank obtained in step (4) is put into high vacuum sintering furnace into 1050 DEG C to sinter 2 hours,
900 DEG C of one-level temperature, time 2 h, 500 DEG C of second annealing temperature, 3 hours time,
The permanent-magnet material (neodymium-iron-boron magnetic material) of addition graphene powder is made.
(6) permanent-magnet material obtained in step (5) is attached and permanent magnetism healing accelerating dressing is made on a carrier layer.
Check experiment：
Graphene powder is added without in step (3), remaining operation is identical with embodiment, is made and does not add graphene powder
Permanent-magnet material.
The permanent-magnet material sample for the addition graphene powder produced to embodiment 1 and the magnetic without addition graphene powder
Material sample carries out magnetism testing, shown in test result table 1：
The magnetic property testing result of table 1
| Classification | Performance | Specification | State | Br(KGs) | BHm(MGOe) | Hcj(KOe) |
| Add graphene | 42SH | 10×10×15 | Black-film | 13.11 | 41.96 | 21.62 |
| Do not add graphene | 42SH | 10×10×15 | Black-film | 13.14 | 42.3 | 20.73 |
The permanent-magnet material sample for the addition graphene powder produced to embodiment 1 and the magnetic without addition graphene powder
Material sample carries out mechanical property (compression strength) test, shown in test result table 2：
The mechanics properties testing result of table 2
| Classification | Performance | Specification | State | Compression strength (N/mm2) |
| Add graphene | 42SH | 10×10×15 | Black-film | 850 |
| Do not add graphene | 42SH | 10×10×15 | Black-film | 775 |
Embodiment 2
The preparation method of permanent magnetism healing accelerating dressing, comprises the following steps：
(1) model N48 magnetic materials are selected, its group is grouped into：
Nd31.8Fe65.58B1.02Co1.0Cu0.1Al0.3Ga0.2, component design with taking raw material, then by raw material in vacuum induction slab stove
In be smelted into slab, the average thickness of slab is 0.2-0.45mm；
(2) the Nd-Fe-B alloy casting pieces obtained in step (1) are positioned over progress hydrogen decrepitation processing in hydrogen crushing furnace,
Obtain primary flour of the granularity within 10mm；
(3) the primary flour obtained in step (2) is milled to particle diameter range in 3-5 μm through air-flow grinding process
NdFeB magnetic powder, for example, particle diameter is respectively 3 μm, 4 μm, 5 μm, 0.06wt% graphene powders are added under nitrogen protection
(thickness 3-5nm, a diameter of 50-1000nm) is well mixed through blending processes of powders, controls the carbon content in mixed powder in 800-
Between 1200ppm.
(4) by the mixed powder obtained in step (3) in 1.2T magnetic fields it is vertical orientated compressing, then through isostatic pressed
Technique is pressed into base；
(5) blank obtained in step (4) is put into high vacuum sintering furnace into 1000 DEG C to sinter 2 hours, one-level tempering temperature
900 DEG C of degree, time 2 h, 500 DEG C of second annealing temperature, 3 hours time, the permanent-magnet material (neodymium for adding graphene powder is made
Fe-Mn magnetism material).
(6) permanent-magnet material obtained in step (5) is attached and permanent magnetism healing accelerating dressing is made on a carrier layer.
Check experiment：
Graphene powder is added without in step (3), remaining operation is identical with embodiment, is made and does not add graphene powder
Permanent-magnet material.
The permanent-magnet material sample for the addition graphene powder produced to embodiment 2 and the magnetic without addition graphene powder
Material sample carries out magnetism testing, shown in test result table 3：
The magnetic property testing result of table 3
| Classification | Performance | Specification | State | Br(KGs) | BHm(MGOe) | Hcj(KOe) |
| Add graphene | 42SH | 10×10×15 | Black-film | 13.65 | 44.73 | 13.25 |
| Do not add graphene | 42SH | 10×10×15 | Black-film | 13.72 | 45.23 | 12.18 |
The permanent-magnet material sample for the addition graphene powder produced to embodiment 2 and the magnetic without addition graphene powder
Material sample carries out mechanical property (compression strength) test, shown in test result table 4：
The mechanics properties testing result of table 4
| Classification | Performance | Specification | State | Compression strength (N/mm2) |
| Add graphene | 42SH | 10×10×15 | Black-film | 885 |
| Do not add graphene | 42SH | 10×10×15 | Black-film | 786 |
The foregoing is only a specific embodiment of the invention, but protection scope of the present invention is not limited thereto, any
Those familiar with the art the invention discloses technical scope in, change or replacement can be readily occurred in, should all be contained
Cover within protection scope of the present invention.Therefore, protection scope of the present invention should be based on the protection scope of the described claims.
Claims (10)
1. a kind of preparation method of permanent magnetism healing accelerating dressing, it is characterised in that comprise the following steps：
(1) NdFeB magnetic powder and graphene powder are mixed and is configured to mixed powder, the content of the graphene powder is described
The 0.03-0.20wt% of mixed powder；
(2) mixed powder obtained in step (1) is orientated in magnetic field and is pressed into blank；
(3) heat treatment is sintered to the blank obtained in step (2), obtains permanent-magnet material；
(4) permanent-magnet material obtained in step (3) is attached and permanent magnetism healing accelerating dressing is made on a carrier layer.
2. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), the neodymium iron boron
The composition of magnetic is RwQxMyNz, wherein, R, Q, M, N representative element species, R Pr, Nd, Dy, Tb, Ho and/or Gd；Q is Fe
And/or Co；M is B element；N is Al, Nb, Zr, Cu, Ga, Mo, W and/or V；29≤w≤33；60≤x≤69；0.98≤y≤
1.2；0≤z≤3；W+x+y+z=100.
3. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), the mixed powder
Carbon content is 300-2500ppm in body.
4. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), described neodymium iron
The particle diameter of boron magnetic powder is 2-10um.
5. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), the graphene
The thickness of powder is 3-5nm, a diameter of 50-1000nm of the graphene powder.
6. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), the neodymium iron boron
Magnetic is mixed with the graphene powder under the protection of inert gas.
7. the preparation method of permanent magnetism healing accelerating dressing according to claim 6, it is characterised in that the inert gas is nitrogen.
8. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (1), crushed by hydrogen
The Nd Fe B alloys slab that thickness is 0.2-10mm is processed into the primary flour that particle diameter is below 10mm, then by primary flour
The NdFeB magnetic powder is obtained through Gas grinding.
9. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (2), by the mixing
Powder is orientated and preliminary compressing in more than 1.2T magnetic field, is then carried out isostatic pressed processing again and is pressed into blank.
10. the preparation method of permanent magnetism healing accelerating dressing according to claim 1, it is characterised in that in step (3), described burning
Knot heat treatment sinters 1-4 hours for the blank is placed in vacuum sintering furnace, at 1000-1300 DEG C；Then in 800-1000
1-4 hours are tempered at DEG C；1-4 hours are tempered again at 400-600 DEG C.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050081959A1 (en) * | 2003-10-15 | 2005-04-21 | Kim Andrew S. | Method of preparing micro-structured powder for bonded magnets having high coercivity and magnet powder prepared by the same |
| CN101732756A (en) * | 2008-11-05 | 2010-06-16 | 曾家宏 | Nano strongly-magnetic wound healing accelerating dressing |
| CN103212714A (en) * | 2013-04-27 | 2013-07-24 | 安徽大地熊新材料股份有限公司 | Method for preparing neodymium iron boron material |
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2017
- 2017-08-22 CN CN201710727037.8A patent/CN107545971A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20050081959A1 (en) * | 2003-10-15 | 2005-04-21 | Kim Andrew S. | Method of preparing micro-structured powder for bonded magnets having high coercivity and magnet powder prepared by the same |
| CN101732756A (en) * | 2008-11-05 | 2010-06-16 | 曾家宏 | Nano strongly-magnetic wound healing accelerating dressing |
| CN103212714A (en) * | 2013-04-27 | 2013-07-24 | 安徽大地熊新材料股份有限公司 | Method for preparing neodymium iron boron material |
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Application publication date: 20180105 |