CN106935392A - Hot pressing nanocrystalline anisotropic magnet - Google Patents
Hot pressing nanocrystalline anisotropic magnet Download PDFInfo
- Publication number
- CN106935392A CN106935392A CN201710137153.4A CN201710137153A CN106935392A CN 106935392 A CN106935392 A CN 106935392A CN 201710137153 A CN201710137153 A CN 201710137153A CN 106935392 A CN106935392 A CN 106935392A
- Authority
- CN
- China
- Prior art keywords
- magnetic field
- hot
- magnet
- magnetic
- anisotropic magnet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/02—Compacting only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/14—Both compacting and sintering simultaneously
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/032—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials
- H01F1/04—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of hard-magnetic materials metals or alloys
- H01F1/047—Alloys characterised by their composition
- H01F1/053—Alloys characterised by their composition containing rare earth metals
- H01F1/055—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5
- H01F1/057—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B
- H01F1/0571—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
- H01F1/0575—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
- H01F1/0576—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together pressed, e.g. hot working
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/0266—Moulding; Pressing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
- B22F3/12—Both compacting and sintering
- B22F3/14—Both compacting and sintering simultaneously
- B22F2003/145—Both compacting and sintering simultaneously by warm compacting, below debindering temperature
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/04—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
- B22F2009/045—Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling by other means than ball or jet milling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Power Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Manufacturing Cores, Coils, And Magnets (AREA)
- Hard Magnetic Materials (AREA)
Abstract
The present invention discloses the magnetically hard alloy such as a kind of method that utilization hot-pressing technique prepares nanocrystalline anisotropic magnet, melting neodymium iron boron, samarium Cobalt, aluminium nickel cobalt, Manganese bismuths, samarium iron；The magnetic powder of irregular shape is made after getting rid of band and airflow milling；Nano-magnetic powder is put into the Magnetic field press protected with nitrogen, magnetic field orientating and die mould is carried out；Blank is put into hot press die, under argon gas protection, compacting obtains anisotropy magnet.Compared with conventional sintering or thermal deformation technique, hot pressing time is short, and temperature is low, energy-saving, process is simple, low cost for the present invention；Nearly end size shaping, can be not required to or need to grind processing less, and recovery rate is higher, and the degree of orientation is high.The beneficial effects of the invention are as follows ensure that magnetic property on the basis of heavy rare earth element is not increased, and make the performance enhancement of magnet.The magnet applications are in fields such as small and special electric machine, Magnetic Sensors.
Description
Technical field
It is specifically a kind of to utilize hot pressing skill particularly for the magnet of hot pressing the present invention relates to RE permanent magnetic alloy
The method that art prepares nanocrystalline anisotropic magnet.
Background technology
The single domain with several nanoscales is prepared using low temperature, surfactant auxiliary externally-applied magnetic field high-energy ball-milling process
Nano-magnetic powder, by having the degree of orientation high after magnetic field orientating, key technology is provided to prepare high-performance anisotropic magnet powder.
Hot pressing neodymium iron boron possesses extremely strong competitiveness in the neodymium iron boron field for substituting addition heavy rare earth.Heat pressing process can be
Ensure coercivity on the basis of addition heavy rare earth element less.Compared with traditional thermal deformation technique, hot pressing time is short, and temperature is low, section
Can consumption reduction, process is simple, low cost；Nearly end size shaping, can be not required to or need to grind processing less, and recovery rate is higher, and the degree of orientation is high.By
Then nanocrystalline, so corrosion resistance ratio is sintered, some purposes can be not required to plating or electrophoresis.Due to be it is nanocrystalline, can be without
Or Dy and Tb is used less, and 2%Dy is saved than the ad eundem sintering trade mark, cost of material is relatively low.Magnetic is similar to sintering.Grain boundary decision is improved
Coercivity potentiality are larger, are capable of achieving without heavy rare earth SHT grade industrialization.Hot pressing has the features such as efficient, low energy, environmental protection, in work
Have wide practical use in industry production.
The content of the invention
It is an object of the invention to provide a kind of method that utilization hot-pressing technique prepares nanocrystalline anisotropic magnet, to have
There is good cost performance and processing characteristics, reduce production cycle and the cost of magnet.
In order to reach above-mentioned purpose, solution of the invention is：
A kind of method that utilization hot-pressing technique prepares nanocrystalline anisotropic magnet, comprises the following steps：
Step (1), alloy is smelted into by neodymium iron boron, samarium Cobalt, aluminium nickel cobalt, Manganese bismuths, samarium iron respectively；
Step (2), is made the magnetic powder of Different Rule shape after getting rid of band and airflow milling, gets rid of tape speed 5-40m/s,
It is 0.3-1MPa using the air pressure to spray formula airflow milling, nozzle, classification wheel speed is 3000-4000rpm, is obtained after airflow milling
It is 3 μm to obtain neodymium iron boron powder particle mean size；
Step (3), 2nm- is prepared by above-mentioned powder using low temperature, surfactant auxiliary externally-applied magnetic field high-energy ball-milling process
1 μm of nano-magnetic powder；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；
Magnetic field intensity 1-9 teslas, pressure is 0.1 to 3 minutes 10MPa-400MPa press times；
Step (5), hot press die is put into by above-mentioned blank, argon gas protection under, hot pressing temperature at 150 DEG C to 700 DEG C,
Pressure 10MPa-400MPa, compacting soaking time 0.5 to 5 minutes, obtains anisotropy magnet.
After using such scheme, compared with prior art, the beneficial effects of the invention are as follows not increasing heavy rare earth element
On the basis of ensure that magnetic property, and make the performance enhancement of magnet.The magnet applications are in fields such as small and special electric machine, Magnetic Sensors.
Compared with conventional sintering method, hot pressing time is short, and temperature is low, energy-saving, process is simple, low cost for the present invention；Closely
Whole size shaping, can be not required to or need to grind processing less, and recovery rate is higher, and the degree of orientation is high.
Specific embodiment
Embodiment 1
Step (1), by smelting neodymium-iron-boron into alloy；
Step (2), is made the magnetic powder of irregular shape after getting rid of band and airflow milling, gets rid of tape speed 15m/s, uses
To spray formula airflow milling, the air pressure of nozzle is 0.3MPa, and classification wheel speed is 3000rpm；
Step (3), receiving for externally-applied magnetic field high-energy ball-milling process 10nm is aided in by above-mentioned powder using low temperature, surfactant
Rice magnetic；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；
The tesla of magnetic field intensity 2, pressure is 100MPa, 1 minute press time；
Step (5), hot press die is put into by above-mentioned blank, and under argon gas protection, hot pressing temperature is arrived at 620 DEG C, pressure
70MPa, compacting soaking time 1 minute, obtains anisotropy magnet.
Embodiment 2
(Manganese bismuths are smelted into alloy to step by 1) ,；
Step (2), is made the magnetic powder of irregular shape after getting rid of band and airflow milling, gets rid of tape speed 20m/s, uses
To spray formula airflow milling, the air pressure of nozzle is 1MPa, and classification wheel speed is 3000rpm；
Step (3), receiving for externally-applied magnetic field high-energy ball-milling process 50nm is aided in by above-mentioned powder using low temperature, surfactant
Rice magnetic；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；
The tesla of magnetic field intensity 2, pressure is 0.5 minute 30MPa press time；
Step (5), hot press die is put into by above-mentioned blank, and under argon gas protection, hot pressing temperature is in 250 DEG C, pressure
20MPa, compacting soaking time 0.5 minute, obtains anisotropy magnet.
Embodiment 3
Step (1), alloy is smelted into by samarium Cobalt；
Step (2), is made the magnetic powder of irregular shape after getting rid of band and airflow milling, gets rid of tape speed 25m/s, uses
To spray formula airflow milling, the air pressure of nozzle is 0.6MPa, and classification wheel speed is 4000rpm；
Step (3), receiving for externally-applied magnetic field high-energy ball-milling process 20nm is aided in by above-mentioned powder using low temperature, surfactant
Rice magnetic；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；
The tesla of magnetic field intensity 2, pressure is 3 minutes 200MPa press times；
Step (5), hot press die is put into by above-mentioned blank, and under argon gas protection, hot pressing temperature is in 650 DEG C, pressure
100MPa, compacting soaking time 2 minutes, obtains anisotropy magnet.
Embodiment 4
Step (1), by smelting neodymium-iron-boron into alloy；
Step (2), is made the magnetic powder of irregular shape after getting rid of band and airflow milling, gets rid of tape speed 15m/s, uses
To spray formula airflow milling, the air pressure of nozzle is 0.9MPa, and classification wheel speed is 4000rpm；
Step (3), aids in externally-applied magnetic field high-energy ball-milling process 100nm's by above-mentioned powder using low temperature, surfactant
Nano-magnetic powder；
Step (3), by above-mentioned powder through PVD platings 2nm thick NdCu grain boundary decision phase alloys；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；
The tesla of magnetic field intensity 9, pressure is 02 minute 150MPa press time；
Step (5), hot press die is put into by above-mentioned blank, and under argon gas protection, hot pressing temperature is in 600 DEG C, pressure
70MPa, compacting soaking time 1 minute, obtains anisotropy magnet.
Claims (6)
1. a kind of method that utilization hot-pressing technique prepares nanocrystalline anisotropic magnet, it is characterised in that comprise the following steps：
Step (1), alloy is smelted into by neodymium iron boron, samarium Cobalt, aluminium nickel cobalt, Manganese bismuths, samarium iron respectively；
Step (2), is made the magnetic powder of Different Rule shape after getting rid of band and airflow milling, gets rid of tape speed 5-40m/s, uses
To spray formula airflow milling, the air pressure of nozzle is 0.3-1MPa, and classification wheel speed is 3000-4000rpm, and neodymium is obtained after airflow milling
Iron boron powder particle mean size is 3 μm；
Step (3), 2nm-1 μm is prepared by above-mentioned powder using low temperature, surfactant auxiliary externally-applied magnetic field high-energy ball-milling process
Nano-magnetic powder；
Step (4), above-mentioned nano-magnetic powder is put into the Magnetic field press protected with nitrogen, carries out magnetic field orientating and die mould；Magnetic field
Intensity 1-9 teslas, pressure is 0.1 to 3 minutes 10MPa-400MPa press times；
Step (5), hot press die is put into by above-mentioned blank, and under argon gas protection, hot pressing temperature is in 150 DEG C to 700 DEG C, pressure
10MPa-400MPa, compacting soaking time 0.5 to 5 minutes, obtains anisotropy magnet.
2. the method that a kind of utilization hot-pressing technique as claimed in claim 1 prepares nanocrystalline anisotropic magnet, its feature exists
In：Step (1), described magnetic material include neodymium iron boron, ferrocerium boron, the neodymium iron boron of doping mischmetal, samarium Cobalt, aluminium nickel cobalt,
One or two and two or more composites in the magnetically hard alloy such as Manganese bismuths, samarium iron.
3. the method that a kind of utilization hot-pressing technique as claimed in claim 1 prepares nanocrystalline anisotropic magnet, its feature exists
In：Step (2), gets rid of tape speed 5-40m/s, is 0.3-1MPa, classification rotation using the air pressure to spray formula airflow milling, nozzle
Speed is 3000rpm.
4. the method that a kind of utilization hot-pressing technique as claimed in claim 1 prepares nanocrystalline anisotropic magnet, its feature exists
In：Step (3), the nano-magnetic powder of gained is prepared using high-energy ball-milling process, is aided with low temperature, surfactant and externally-applied magnetic field
Condition, including one of which, two or three additional condition combination.The particle size range of the nano-magnetic powder for being obtained is 2nm-1 μ
m。
5. the method that a kind of utilization hot-pressing technique as claimed in claim 1 prepares nanocrystalline anisotropic magnet, its feature exists
In：Step (4), Magnetic field press is protected with nitrogen, magnetic field intensity 1-9 teslas, and pressure is the 10MPa-400MPa press times 0.1
By 3 minutes.
6. the method that a kind of utilization hot-pressing technique as claimed in claim 1 prepares nanocrystalline anisotropic magnet, its feature exists
In：Step (5), hot press includes vacuumizing or not vacuumizing two kinds, but is both needed to argon gas protection, and mode of heating includes sensing and electricity
Two kinds of resistance heating, low frequency in sensing heating use.Hot pressing temperature at 150 DEG C to 700 DEG C, protect by pressure 10MPa-400MPa, compacting
0.5 to 5 minutes warm time.Hot pressing terminates rear automatic demoulding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710137153.4A CN106935392A (en) | 2017-03-10 | 2017-03-10 | Hot pressing nanocrystalline anisotropic magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710137153.4A CN106935392A (en) | 2017-03-10 | 2017-03-10 | Hot pressing nanocrystalline anisotropic magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106935392A true CN106935392A (en) | 2017-07-07 |
Family
ID=59433822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710137153.4A Pending CN106935392A (en) | 2017-03-10 | 2017-03-10 | Hot pressing nanocrystalline anisotropic magnet |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106935392A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108010706A (en) * | 2017-12-01 | 2018-05-08 | 程桂平 | The preparation method of permanent magnetic speed-adjusting equipment permanent magnet |
| CN108109799A (en) * | 2017-12-01 | 2018-06-01 | 程桂平 | The preparation method of generator permanent magnet |
| CN108109798A (en) * | 2017-12-01 | 2018-06-01 | 程桂平 | The preparation method of transformer permanent magnet |
| CN113674977A (en) * | 2020-05-03 | 2021-11-19 | 绍兴撒母耳新材料科技有限公司 | Hot-pressed nanocrystalline anisotropic magnet |
-
2017
- 2017-03-10 CN CN201710137153.4A patent/CN106935392A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108010706A (en) * | 2017-12-01 | 2018-05-08 | 程桂平 | The preparation method of permanent magnetic speed-adjusting equipment permanent magnet |
| CN108109799A (en) * | 2017-12-01 | 2018-06-01 | 程桂平 | The preparation method of generator permanent magnet |
| CN108109798A (en) * | 2017-12-01 | 2018-06-01 | 程桂平 | The preparation method of transformer permanent magnet |
| CN113674977A (en) * | 2020-05-03 | 2021-11-19 | 绍兴撒母耳新材料科技有限公司 | Hot-pressed nanocrystalline anisotropic magnet |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106935392A (en) | Hot pressing nanocrystalline anisotropic magnet | |
| CN102280240B (en) | Method for preparing sintered NdFeB with low dysprosium content and high performance | |
| EP2869311B1 (en) | Method of manufacturing fully dense Nd-Fe-B magnets with enhanced coercivity and gradient microstructure | |
| CN105513737A (en) | Preparation method of sintered neodymium-iron-boron magnet without containing heavy rare earth elements | |
| CN102347126A (en) | High-performance sintered neodymium-iron-boron (Nd-Fe-B) rare-earth permanent magnet material and manufacturing method thereof | |
| CN103785845B (en) | The preparation method of a kind of minute spherical Sm-Fe-N system permanent magnetism powder | |
| CN107195414A (en) | One kind (Nd, Y) Fe B rare-earth permanent magnets and preparation method thereof | |
| CN105869816A (en) | Mischmetal-mixed neodymium iron boron hot-pressed and hot-deformed magnet and manufacturing method thereof | |
| CN108154986A (en) | A kind of rare-earth permanent magnet of high abundance containing Y and preparation method thereof | |
| CN101174503B (en) | Production method of radiation-orienting magnet ring | |
| CN109346258A (en) | A kind of nano double main phase magnet and preparation method thereof | |
| CN107546027A (en) | The preparation method of low heavy rare earth high-coercive force neodymium iron boron magnetic body | |
| CN103151161A (en) | Method for preparing anisotropic neodymium iron boron magnetic powder through directionally breaking thermal deformed magnet | |
| CN102766835A (en) | Method for preparing high performance SmCo permanent magnet material | |
| CN102982935B (en) | A kind of without heavy rare earth permanent magnetic material and hot pressing method for preparing thereof | |
| CN101393791B (en) | Anisotropic magnetic powder and manufacturing method thereof | |
| CN106816253A (en) | A kind of method of Mn Ga alloy magnetic hardenings | |
| CN102744406B (en) | Method for preparing fully dense anisotropic nanocrystalline neodymium-iron-boron (NdFeB) bulk magnet material | |
| CN104766717A (en) | Method for improving magnetic property of sintered neodymium-iron-boron permanent magnet | |
| CN108666064B (en) | VC-added sintered rare earth permanent magnet material and preparation method thereof | |
| CN104867645B (en) | A kind of nanocrystalline hot-pressed magnets of high-coercive force and preparation method thereof | |
| CN107424696B (en) | A kind of Nd-Fe-B permanent magnet material and preparation method thereof | |
| CN103632789B (en) | A kind of high remanent magnetism Nd-Fe-Bo permanent magnet material and preparation method thereof | |
| CN103680789B (en) | A kind of sintering Nd-Fe-B rare earth permanent magnetic alloy powder and sintering process | |
| CN108777204A (en) | A kind of preparation method of samarium iron nitrogen permanent-magnet powder |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20170707 |
|
| WD01 | Invention patent application deemed withdrawn after publication |