CN108376607A - A kind of preparation method reducing heavy rare earth sintered NdFeB - Google Patents
A kind of preparation method reducing heavy rare earth sintered NdFeB Download PDFInfo
- Publication number
- CN108376607A CN108376607A CN201711495759.1A CN201711495759A CN108376607A CN 108376607 A CN108376607 A CN 108376607A CN 201711495759 A CN201711495759 A CN 201711495759A CN 108376607 A CN108376607 A CN 108376607A
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- CN
- China
- Prior art keywords
- rare earth
- airflow milling
- cooler bin
- heavy rare
- cooled
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- 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.)
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Classifications
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- 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
- H01F41/0293—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 diffusion of rare earth elements, e.g. Tb, Dy or Ho, into permanent magnets
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
- C25D3/00—Electroplating: Baths therefor
- C25D3/02—Electroplating: Baths therefor from solutions
- C25D3/54—Electroplating: Baths therefor from solutions of metals not provided for in groups C25D3/04 - C25D3/50
-
- 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
- H01F1/0577—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 sintered
-
- 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
Abstract
The present invention relates to neodymium iron boron preparation fields, more particularly to a kind of preparation method reducing heavy rare earth sintered NdFeB, pass through the addition of antioxidant, the milling efficiency of airflow milling can be improved in the airflow milling stage, the loss of rare earth richness phase is reduced in the airflow milling stage, reduce oxygen content simultaneously, it is added after airflow milling, the degree of orientation of powder is improved in forming process, improve the performance of product, the content of oxygen in forming process also can be effectively controlled simultaneously, the content of the above control oxygen, it can guarantee the abundant of liquid-phase sintering in sintering process, and then during composition design, total amount of rare earth can be reduced, reduce the addition of heavy rare earth, effectively reduce formulation cost；It is being sintered and is improving helium degree of protection in drawing process, while by the setting of cooler bin, realizing separation cooling; the steady temperature of insulating box, level-one tempering furnace, second annealing stove is not influenced; the production of next batch product is not influenced, while improving efficiency, reduces energy consumption.
Description
Technical field
The present invention relates to neodymium iron boron preparation field, more particularly to a kind of preparation method reducing heavy rare earth sintered NdFeB.
Background technology
Sintered NdFeB has excellent magnetic property, has been widely used in every field rapidly since emerging.
During manufacturing sintered NdFeB permanent magnets, powder processed, formative stage are very easy to bring oxygen into.Oxygen consumption is a certain amount of heavy dilute
Soil causes the waste of cost, and when too high oxygen level, rich mutually insufficient, product is thought drastically to deteriorate.How by the oxygen content of magnet
It is one of the critical issue that sintered NdFeB permanent magnets performance improves to control reduced levels.So adding a certain amount of oxygen
Agent is a kind of effective means of control oxygen content, while simplify control process, batch making High Performance of Sintered NdFeB,
This patent has studied influence of the addition of antioxidant to production technology and magnetic property.
Currently, being proposed in patent ZL201610270478.5 a kind of by optimizing component and control melting casting temperature
It spends to optimize slab microstructure and the control technological parameters such as powder volume average particle size SMD and size distribution X90/X10,
To prepare 52M and 48H high-performance neodymium-iron-boron magnets, it is mentioned that antioxidant is added in the broken coarse powder obtained of hydrogen, it is made
But lubricant is added after fine powder, but can not prevent fine powder from continuing to aoxidize, while in entirely cooling drawing process when cooling consuming
Between it is long, high efficiency production can not be formed.
Invention content
It is an object of the invention to provide a kind of high performance sintered neodymium-iron-borons, reduce the preparation method of the addition of heavy rare earth.
The technical problem of the present invention is mainly addressed by following technical proposals：
A kind of preparation method reducing heavy rare earth sintered NdFeB, it is characterised in that：
A. neodymium iron boron raw material is subjected to melting using intermediate frequency vaccum sensitive stove, and is cast into slab alloy；
B. slab made from step A is crushed stove in hydrogen to be crushed, coarse powder is made；
C. 0.1% antioxidant is added in the coarse powder made from step B, use airflow milling by coarse powder wear into average grain diameter for
3.1-3.4 microns of fine powder, and 0.05%-0.2% antioxidants are added again；
D. fine powder made from step C is placed in the magnetic fields 1500kA/m using vertical steel molding and cold isostatic compaction work
Green compact is made in skill；
E. under helium protection；By green compact made from step D, 4 are sintered using 1020 DEG C~1080 DEG C of constant temperature oven
Hour；
F. under helium protection, crude product made from step E is cooled to room temperature using pipeline is defeated to sending in cooler bin, it can
To carry out next group production in being sintered constant temperature oven, cooling crude product is delivered to 900 DEG C of level-one tempering furnace and is returned
Fire 2.5 hours, is again fed to cooler bin and is cooled to room temperature, and 560 DEG C of second annealing stove is delivered to after cooling and is returned
Fire 3.5 hours is sent into cooler bin and is cooled to room temperature after tempering, the stove reserved every time can be carried out next batch
Production after forming assembly line, does not have to consume cooling time, improves production efficiency；Finished product.
Advantageous effect of the invention：
By the addition of antioxidant, the milling efficiency of airflow milling can be improved in the airflow milling stage, in the airflow milling stage
The loss of rare earth richness phase is reduced, while reducing oxygen content, is added after airflow milling, the degree of orientation of powder is improved in forming process,
The performance of product is improved, while also can effectively control the content of oxygen in forming process, the content of the above control oxygen can guarantee burning
Liquid-phase sintering is abundant during knot, and then during composition design, can reduce total amount of rare earth, reduces adding for heavy rare earth
Add, effectively reduces formulation cost；It is being sintered and is improving helium degree of protection, while setting by cooler bin in drawing process
It sets, realizes separation cooling, do not influence the steady temperature of insulating box, level-one tempering furnace, second annealing stove, do not influence next batch production
The production of product, while efficiency is improved, reduce energy consumption.
Specific implementation mode
Below by embodiment, the technical solutions of the present invention will be further described.
Embodiment 1
A. by neodymium iron boron raw material alloy (Nd13.5FebalAl0.4B6) using the progress melting of intermediate frequency vaccum sensitive stove, and be cast into
Slab alloy；
B. slab made from step A is crushed stove in hydrogen to be crushed, coarse powder is made；
C. 0.1% antioxidant is added in the coarse powder made from step B, use airflow milling by coarse powder wear into average grain diameter for
3.1-3.4 microns of fine powder, and 0.2% antioxidant and 0.5% heavy rare earth (element powders such as yttrium containing dysprosium) are added again；
D. fine powder made from step C is placed in the magnetic fields 1500kA/m using vertical steel molding and cold isostatic compaction work
Green compact is made in skill；
E. under helium protection；By green compact made from step D, 4 are sintered using 1020 DEG C~1080 DEG C of constant temperature oven
Hour；
F. under helium protection, crude product made from step E is cooled to room temperature using pipeline is defeated to sending in cooler bin, it can
To carry out next group production in being sintered constant temperature oven, cooling crude product is delivered to 900 DEG C of level-one tempering furnace and is returned
Fire 2.5 hours, is again fed to cooler bin and is cooled to room temperature, and 560 DEG C of second annealing stove is delivered to after cooling and is returned
Fire 3.5 hours is sent into cooler bin and is cooled to room temperature after tempering；Finished product.
Embodiment 2
A. by neodymium iron boron raw material alloy (Nd13.5FebalAl0.4B6) using the progress melting of intermediate frequency vaccum sensitive stove, and be cast into
Slab alloy；
B. slab made from step A is crushed stove in hydrogen to be crushed, coarse powder is made；
C. 0.1% antioxidant is added in the coarse powder made from step B, use airflow milling by coarse powder wear into average grain diameter for
3.1-3.4 microns of fine powder, and 0.1% antioxidant and 1% heavy rare earth (element powders such as yttrium containing dysprosium) are added again；
D. fine powder made from step C is placed in the magnetic fields 1500kA/m using vertical steel molding and cold isostatic compaction work
Green compact is made in skill；
E. under helium protection；By green compact made from step D, 4 are sintered using 1020 DEG C~1080 DEG C of constant temperature oven
Hour；
F. under helium protection, crude product made from step E is cooled to room temperature using pipeline is defeated to sending in cooler bin, it can
To carry out next group production in being sintered constant temperature oven, cooling crude product is delivered to 900 DEG C of level-one tempering furnace and is returned
Fire 2.5 hours, is again fed to cooler bin and is cooled to room temperature, and 560 DEG C of second annealing stove is delivered to after cooling and is returned
Fire 3.5 hours is sent into cooler bin and is cooled to room temperature after tempering；Finished product.
Embodiment 3
A. by neodymium iron boron raw material alloy (Nd13.5FebalAl0.4B6) using the progress melting of intermediate frequency vaccum sensitive stove, and be cast into
Slab alloy；
B. slab made from step A is crushed stove in hydrogen to be crushed, coarse powder is made；
C. 0.1% antioxidant is added in the coarse powder made from step B, use airflow milling by coarse powder wear into average grain diameter for
3.1-3.4 microns of fine powder, and 0.05% antioxidant and 2.5% heavy rare earth (element powders such as yttrium containing dysprosium) are added again；
D. fine powder made from step C is placed in the magnetic fields 1500kA/m using vertical steel molding and cold isostatic compaction work
Green compact is made in skill；
E. under helium protection；By green compact made from step D, 4 are sintered using 1020 DEG C~1080 DEG C of constant temperature oven
Hour；
F. under helium protection, crude product made from step E is cooled to room temperature using pipeline is defeated to sending in cooler bin, it can
To carry out next group production in being sintered constant temperature oven, cooling crude product is delivered to 900 DEG C of level-one tempering furnace and is returned
Fire 2.5 hours, is again fed to cooler bin and is cooled to room temperature, and 560 DEG C of second annealing stove is delivered to after cooling and is returned
Fire 3.5 hours is sent into cooler bin and is cooled to room temperature after tempering；Finished product.
It can find that antioxidant is added after airflow milling in three embodiments, can effectively control oxygen in forming process
Content, can guarantee the abundant of liquid-phase sintering in sintering process, and then during composition design, it is total heavy rare earth can be reduced
Amount, reduces the addition of heavy rare earth.
One embodiment of the present invention has been described in detail above, but the content is only the preferable of the utility model
Embodiment should not be construed as limiting the practical range of the present invention.It is all according to equivalent change made by the present patent application range with
Improve etc., the patent that should all still belong to the present invention is contained within the patent covering scope of the utility model.
Claims (1)
1. a kind of preparation method reducing heavy rare earth sintered NdFeB, it is characterised in that：
A. neodymium iron boron raw material is subjected to melting using intermediate frequency vaccum sensitive stove, and is cast into slab alloy；
B. slab made from step A is crushed stove in hydrogen to be crushed, coarse powder is made；
C. 0.1% antioxidant is added in the coarse powder made from step B, uses airflow milling that coarse powder is worn into average grain diameter as 3.1-
3.4 microns of fine powder, and 0.05%-0.2% antioxidants are added again；
D. fine powder made from step C is placed in the magnetic fields 1500kA/m using vertical steel molding and cold isostatic compaction technique, system
Obtain green compact；
E. under helium protection；By green compact made from step D, it is sintered 4 hours using 1020 DEG C~1080 DEG C of constant temperature oven；
F. it under helium protection, by crude product made from step 5), is cooled to room temperature to sending in cooler bin, will cool down using pipeline is defeated
Crude product be delivered to 900 DEG C of level-one tempering furnace and carry out tempering 2.5 hours, be again fed to cooler bin and be cooled to room temperature, it is cooling
After be delivered to 560 DEG C of second annealing stove and carry out tempering 3.5 hours, cooler bin is sent into after tempering and is cooled to room temperature；
Finished product.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711495759.1A CN108376607A (en) | 2017-12-31 | 2017-12-31 | A kind of preparation method reducing heavy rare earth sintered NdFeB |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711495759.1A CN108376607A (en) | 2017-12-31 | 2017-12-31 | A kind of preparation method reducing heavy rare earth sintered NdFeB |
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| CN108376607A true CN108376607A (en) | 2018-08-07 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110444359A (en) * | 2019-07-09 | 2019-11-12 | 浙江东阳东磁稀土有限公司 | A kind of method and additive reducing sintered neodymium iron boron material oxygen content |
| CN111724962A (en) * | 2020-07-01 | 2020-09-29 | 宁波美固力磁电有限公司 | Oxidation-resistant treatment process for neodymium iron boron magnet |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110444359A (en) * | 2019-07-09 | 2019-11-12 | 浙江东阳东磁稀土有限公司 | A kind of method and additive reducing sintered neodymium iron boron material oxygen content |
| CN110444359B (en) * | 2019-07-09 | 2021-09-14 | 浙江东阳东磁稀土有限公司 | Method for reducing oxygen content of sintered neodymium-iron-boron material and additive |
| CN111724962A (en) * | 2020-07-01 | 2020-09-29 | 宁波美固力磁电有限公司 | Oxidation-resistant treatment process for neodymium iron boron magnet |
| CN111724962B (en) * | 2020-07-01 | 2021-01-01 | 宁波美固力磁电有限公司 | Oxidation-resistant treatment process for neodymium iron boron magnet |
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