CN105741994B - A kind of preparation method of neodymium iron boron magnetic body - Google Patents
A kind of preparation method of neodymium iron boron magnetic body Download PDFInfo
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- CN105741994B CN105741994B CN201610081348.7A CN201610081348A CN105741994B CN 105741994 B CN105741994 B CN 105741994B CN 201610081348 A CN201610081348 A CN 201610081348A CN 105741994 B CN105741994 B CN 105741994B
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- 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
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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
Abstract
A kind of preparation method of neodymium iron boron magnetic body, comprises the following steps：Step S1, prepare neodymium iron boron configuration powder；Step S2, under the conditions of magnetic field orientating neodymium iron boron configured into powder pressing into primary billet；Then demagnetize, and primary billet is pressed into green compact under 100MPa 1500MPa pressure；The green compact are machined into the shape of neodymium iron boron magnetic body finished product again；Step S3, will be machined after green sintering into neodymium iron boron magnetic body finished product.The present invention neodymium iron boron magnetic body preparation method realize it is almost lossless in neodymium-iron-boron production procedure, meanwhile, substantially increase the magnetic behavior and decay resistance of neodymium iron boron magnetic body, it is practical.
Description
Technical field
The present invention relates to magnet preparing technical field, more particularly to a kind of preparation method of neodymium iron boron magnetic body.
Background technology
Neodymium iron boron magnetic body is referred to as " magnetic king ", with highest remanent magnetism and magnetic energy product in current all kinds of permanent-magnet materials, simultaneously
Also possesses very high coercivity, with the raising of commercial neodymium iron boron magnetic body performance, neodymium iron boron device is towards small-sized, ultra-thin, abnormal shape
Change development；Neodymium iron boron product of the piece weight below 5 grams accounts for more than the 80% of all over products, such as in some smart mobile phones
Neodymium iron boron magnetic body, its magnet thickness only 0.5mm.
The Conventional process of neodymium iron boron magnetic body comprises the following steps：Dispensing, alloy melting casting (getting rid of band), powder processed, pressure
Be made type, vacuum-sintering, cutting, grinding, again surface treated be finished product.The neodymium iron prepared by conventional production methods
Boron magnet has the characteristics that：
1st, neodymium iron boron configuration powder is harder crisp, the excessive easy layering of pressure, cracking when die is suppressed.Therefore, for existing
There is the compacting blank before being sintered under technology, its density is 3-5.5g/cm3, the 40-70% of product density is (through burning after only sintering
It is 7.2-7.65g/cm to tie obtained neodymium-iron-boron volume density3)；It is liquid-phase sintering, such as fruit product plus NbFeB sintered process
Amount of contraction is excessive in sintering process, is just more prone to deformation.Meanwhile, shrinkage factor that prior art is caused is excessive to have an effect on neodymium iron
The degree of orientation and HCJ of boron magnet.
2nd, neodymium iron boron configuration powder particles are only 2-5 μm, and poor fluidity, mould loading density is low, i.e., using the side of granulation
Method is improved；Its " grain " is made, actually fine powder aggregate, not compact metal particle, loading density only increases to 2g/cm3, compacting
Improvement is not also obvious.Miniature precision device is suppressed, difficulty is very big, extremely inefficient.
3rd, it is necessary to which more than 1T magnetic field orients powder when neodymium iron boron magnetic body is compressing, mould is complicated so that small-sized device
The compacting difficulty of part is very big.
4th, the neodymium iron boron magnetic body production of more than N45 high energy products needs to control the oxygen content of finished product within 3000PPM,
And neodymium iron boron powder is easily aoxidized in atmosphere, or even spontaneous combustion.Therefore, sealing whole compressing process turns into common practice,
This further complicates forming process.
Based on above reason, current small-sized neodymium iron boron magnetic body is that the massive material cutting grinding after sintering is formed；
For the bigger neodymium iron boron magnetic body of the ratio between surface area and volume, the destruction of its surface crystal structure caused by being machined is brought
Comprehensive magnetic can decline more obvious, and different according to neodymium iron boron magnetic body specific surface area, comprehensive magnetic can decline degree in 5-40%.Pin
To the problem, generate to neodymium iron boron finished surface by sputtering plating, plating, heating and vat blue RS infiltration dysprosium, terbium, neodymium metal
The remedial techniques such as crystal structure are repaired to recover the technology of raising neodymium iron boron magnetic body performance, but the neodymium iron prepared using these technologies
Boron product cost is high, and uniformity is poor.In addition, the easy corrosion of neodymium iron boron magnetic body, the chemical plating that has been this development and application, epoxy plating,
Sputtering such as is aluminized at the complex and expensive technique.The surface that the corrosion of neodymium iron boron magnetic body is also machined destruction with it is closely related.
In addition, the cutting grinding proportion of goods damageds of small-sized neodymium iron boron magnetic body are 20-60%；The waste oil mud that cutting grinding is produced (is cut
Cut and the mixture that oil and neodymium iron boron are considered to be worth doing cut in grinding) reclaim and (because seriously polluted, to reclaim useless mud by long-distance transport and often exist
Away from neodymium iron boron factory by-place carry out, it is difficult to supervise), oxidation calcination, concentrated acid dissolving, precipitation separation, a large amount of water neutralize
Washing, rare earth element extract and separate, reprecipitation washing, into chemical processes such as rare earth oxides, and again, electrolysis for production is for calcination
Numerous and diverse step such as rare earth metal, whole process causes the irretrievable loss of rare earth material 20% again, while producing a large amount of extremely difficult
The waste oil waste water and gas of processing, one ton of neodymium iron boron waste oil mud removal process about produces more than 1000t spent acid waste water, at present China's neodymium
About 110,000 tons of iron boron magnet yield, the mud that gives up is up to 50,000 tons, and spent acid waste water reclaims the amount of pollutants produced huge more than 50,000,000 tons
Greatly.
The content of the invention
The present invention is directed in existing neodymium-iron-boron production procedure, and mechanical processing steps can give the table of neodymium iron boron magnetic body
Damage is caused in face, while the problem of bringing substantial amounts of waste material, it is proposed that a kind of preparation method of neodymium iron boron magnetic body.
The present invention proposes a kind of preparation method of neodymium iron boron magnetic body, comprises the following steps：
Step S1, prepare neodymium iron boron configuration powder；
Step S2, under the conditions of magnetic field orientating neodymium iron boron configured into powder pressing into primary billet；Then demagnetize, and
Primary billet is pressed into green compact under 100MPa-1500MPa pressure；The green compact are machined into neodymium iron boron magnetic body finished product again
Shape；
Step S3, will be machined after green sintering into neodymium iron boron magnetic body finished product.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, the step S1 includes：
29-35wt%R, 0-4wt%M, 0.9-1.1wt%B and 59.9-70.1wt%Fe are weighed, and is mixed；Here, R
For the one or more in La, Ce, Pr, Nd, Gd, Ho, Tb and Dy；M is one kind or many in Co, Al, Cu, Zr, Ga, Nb
Kind；The neodymium iron boron raw material of mixing is quick-fried or direct powder processed obtains neodymium iron boron configuration powder by hydrogen through vacuum melting, ingot casting or after getting rid of band
Material.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, in step s 2, mechanical processing process includes cutting, mill
Cut, peripheral milling, one or more of drilling and digging step.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, mechanical processing process enters in inert atmosphere or protection oil
OK.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, the break flour produced by mechanical processing process is through filtering
Afterwards, it is mixed into neodymium iron boron configuration powder；Rim charge produced by mechanical processing process after crushed, is mixed into neodymium iron boron configuration powder
In.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, in step s3, it is machined after green compact clamping
On fixture, and it is put into magazine, is then placed in vacuum sintering furnace and sinters together；Or
Using green compact of the powder burial do not reacted with green compact after machined, and burning in vacuum sintering furnace is placed on together
Knot.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, green layer of the polylith after machined is laminated tightly,
And pad is lined between green compact, then it is put into vacuum sintering furnace and sinters together.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, step S3 also includes：
The neodymium iron boron magnetic body fixed using fixture after the completion of sintering, and apply external force compression, and together at 300 DEG C -1200
More than 20min is incubated at DEG C；Then more than 20min is incubated at 300 DEG C -700 DEG C, makes the shape and fixture of neodymium iron boron magnetic body
Shape is matched, and neodymium iron boron magnetic body finally is cooled into room temperature, obtains the finished product of neodymium iron boron magnetic body.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, the fixture be flat-bottom structure, concave-convex curved surface structure or
Hollow support rod structure.
In the preparation method of the above-mentioned neodymium iron boron magnetic body of the present invention, in step s3, by reducing agent with it is machined after
Green compact be put into together in vacuum sintering furnace；The reducing agent include calcium metal, magnesium metal, metallic sodium, calcium hydride, magnesium hydride with
And the one or more in sodium hydride.
The preparation method of the neodymium iron boron magnetic body of the present invention is using 100MPa-1500MPa pressure by raw materials such as neodymium, iron, boron
The neodymium iron boron obtained after dispensing, vacuum melting and powder processed configures powder pressing and carries out machinery into high density green compact, then to green compact
Process to form the shape of finished product, then, sinter finished product into, realize almost lossless in neodymium-iron-boron production procedure
Consumption, meanwhile, the magnetic behavior and decay resistance of neodymium iron boron magnetic body are substantially increased, it is practical.
Embodiment
The technical problem to be solved in the present invention is：In existing neodymium-iron-boron production procedure, mechanical processing steps meeting
Damage is caused on surface to neodymium iron boron magnetic body, while bringing substantial amounts of waste material.With regard to the technical problem, technology proposed by the invention
Thinking is：The raw materials such as neodymium, iron, boron are obtained after dispensing, vacuum melting and powder processed using 100MPa-1500MPa pressure
Neodymium iron boron configures powder pressing into high density green compact, then green compact is machined to form the shape of finished product, then, burns
Form finished product.
Specifically, the preparation method of neodymium iron boron magnetic body of the invention comprises the following steps：
Step S1, prepare neodymium iron boron configuration powder；
This step S1 includes dispensing, vacuum melting, ingot casting or gets rid of band and milling step.Specifically, blending process is：
29-35wt%R, 0-4wt%M, 0.9-1.1wt%B and 59.9-70.1wt%Fe are weighed, and is mixed；Here, R be La, Ce,
One or more in Pr, Nd, Gd, Ho, Tb and Dy；M is the one or more in Co, Al, Cu, Zr, Ga, Nb.Prepare
Neodymium iron boron raw material is quick-fried or direct powder processed obtains neodymium iron boron configuration powder by hydrogen through vacuum melting, ingot casting or after getting rid of band；At this
In, the granularity of neodymium iron boron configuration powder is generally 2-5 μm.
Step S2, under magnetic field orientating condition (wherein, magnetic field intensity is 1.2T-3.0T) neodymium iron boron configured into powder pressing
Into primary billet；Then demagnetize, and primary billet is pressed into green compact under 100MPa-1500MPa pressure；Again by the green compact machine
Tool is processed into the shape of neodymium iron boron magnetic body finished product；
In this step, green compact are that under the conditions of magnetic field orientating, neodymium iron boron is configured into powder using die pressure or rubber molding
Feed liquid is molded.Preparation-obtained green density is big at elevated pressures, and intensity is high, can carry out subsequent mechanical processing.Through surveying
Examination, pressure pressure has following corresponding relation with green density：
| Pressure pressure/MPa | Green density/(g/cm3) |
| 200 | 4.87 |
| 250 | 4.96 |
| 300 | 5.32 |
| 500 | 6.75 |
| 600 | 6.92 |
| 750 | 7.02 |
And from unlike the present invention, the pressure pressure that traditional pressing process is used is generally less than 300MPa, obtain
Green density is generally 3-4.9g/cm3；This make it that the green porosity obtained through traditional pressing process is big, itself and air contact
Area is also big, is easily aoxidized in following process, carrying, loading furnace process, and these situations can cause sintering shrinkage excessive deformation.
Meanwhile, the green strength obtained through traditional pressing process is low, it is impossible to be machined.
Further, in this step, the green compact that are made are pushed in 100MPa-1500MPa pressure, can be being pressed from both sides
After holding or be bonded on corresponding fixture, cut, be ground, peripheral milling, drilling, the mechanical processing process such as digging.Herein, machine
Tool process needs to carry out under inert atmosphere (nitrogen, argon gas or carbon dioxide atmosphere), or in special protection oil
Carry out.And be machined produced by waste material can the reuse after filtering and/or crushing, without powder processed again.Specifically, it is mechanical
Break flour produced by process after filtering, can be mixed into neodymium iron boron configuration powder；Produced by mechanical processing process
Rim charge after crushed, can be mixed into neodymium iron boron configuration powder.
Step S3, will be machined after green sintering into neodymium iron boron magnetic body finished product.
In this step, the green density that obtains through step S2 is high, porosity is small, and it exposes oxidation rate when in atmosphere
Substantially reduce.Simultaneously as density high shrinkage is small, deformation of products situation is greatly reduced.Can be with fixture one during green compact shove charge
Rise and be put into magazine, the technology that burning can also be buried with prior powder metallurgy (adds the powder not reacted with green compact, green compact are buried into branch
Support sintering).For the yielding blank such as ultra-thin, ultra-fine, can after sintering aging strengthening model when shove charge shaping again.Here, will
The powder that green compact are buried is aluminum oxide, graphite, calcium oxide, zirconium oxide, magnesia or rare earth oxide etc..Further, it is also possible to will
Green layer lamination after polylith is machined is tight, and pad is lined between green compact, is then put into vacuum sintering furnace and burns together
Knot.Here, pad can be sheet metal, stationery, potsherd, graphite etc..
In this step, treat after the completion of neodymium iron boron magnetic body sintering, the neodymium iron boron magnetic body is fixed using fixture, and apply external force
Compress, and be incubated more than 20min at 300 DEG C -1200 DEG C together, carry out first time aging strengthening model；Then at 300 DEG C -700
More than 20min is incubated at DEG C, second of aging strengthening model is carried out, the shape of neodymium iron boron magnetic body is matched with the shape of fixture,
Neodymium iron boron magnetic body is finally cooled to room temperature, the finished product of neodymium iron boron magnetic body is obtained.Herein, aging strengthening model process also passes through
Hot mastication neodymium iron boron magnetic body, is allowed to coincide with fixture, serves the purpose to neodymium iron boron magnetic body shaping.Here, fixture can be
Flat-bottom structure, concave-convex curved surface structure or hollow support rod structure.Herein, Ageing Treatment can also use conventional method, will locate
Insulation more than 20min at 300 DEG C -1200 DEG C is direct cooled in the neodymium iron boron magnetic body of sintering temperature, first time timeliness heat is completed
Processing；Then insulation more than 20min at 300 DEG C -700 DEG C is cooled to, is completed at second of aging strengthening model, this traditional aging
Reason mode is adapted to precision prescribed less high product.
Preferably, in this step, can also by reducing agent with it is machined after green compact together be put into vacuum burn
In freezing of a furnace；The reducing agent includes one kind or several in calcium metal, magnesium metal, metallic sodium, calcium hydride, magnesium hydride and sodium hydride
Kind.Reducing agent can improve sintering atmosphere, prevent blank from being aoxidized in sintering process.
For the ease of skilled artisan understands that and implement the present invention, the present invention is done below in conjunction with specific embodiment
Further details of explanation.
First embodiment
With 29wt%Pr-Nd alloys, 2wt%Gd, 0.5wt%Co, 1.0wt%Al, 0.2wt%Cu, 0.9wt%B and
66.4wt%Fe weighs neodymium iron boron raw material, and carries out melting in vacuum is 0.3-0.8Pa vacuum melting furnace, prepares
Neodymium iron boron configuration material rejection tablet, smelting temperature is 1500 DEG C；It is again that neodymium iron boron configuration material rejection tablet progress hydrogen is broken, obtain neodymium iron boron configuration
Coarse powder, here, during hydrogen is broken, desorption temperature is 540 DEG C, and dehydrogenation time is 4.5h.Neodymium iron boron configuration coarse powder is carried out again many
Secondary airflow milling powder, obtains the neodymium iron boron configuration powder of 3 μm of particle diameters.
It is using die that neodymium iron boron configuration powder is tentatively compressing under the conditions of magnetic field orientating, then demagnetize, here,
The pressure tentatively suppressed is 20MPa；Repressurization carries out isostatic pressed to 700MPa, and green compact are made.
Green compact are taken, under an inert atmosphere, by two faces of self-acting grinding machine milled, and are fixed on flitch, now, green compact
Size is 100mm × 100mm × 25.6mm；Then, green compact are placed on cutting machine be processed into size for 25.7mm ×
14.4mm × 1.8mm sheet blank material.Again through chamfer polishing, it is put into sintering magazine, is buried with ceramic powders, and load together
In vacuum sintering furnace；Vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, then to being warming up to 500 in vacuum sintering furnace stove
DEG C, it is incubated 2h；Then, it then will be warming up to 1100 DEG C in vacuum sintering furnace stove, be incubated 4h, be cooled back to room temperature, complete sintering step
Suddenly.
Then, the neodymium iron boron magnetic body for completing sintering step is taken out, the neodymium iron boron magnetic body is fixed using fixture, and apply external force
Compress, and place into vacuum sintering furnace, the vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, 900 are then heated to
DEG C, and 2h is incubated, complete first time Ageing Treatment；Afterwards, argon gas is filled with into vacuum sintering furnace again, is made in vacuum sintering furnace
300 DEG C are quickly cooled to, stops cooling, and the vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, 550 are then heated to
DEG C, and 2h is incubated, complete second of Ageing Treatment.Finally, argon gas is filled with into vacuum sintering furnace, is made cold in vacuum sintering furnace stove
But to room temperature, so as to obtain the finished product for the neodymium iron boron magnetic body that size is 25mm × 14mm × 1.5mm.
The another green compact for taking 100mm × 100mm × 25.6mm specifications are put into sintering magazine, are fitted into vacuum sintering furnace；
Green compact in vacuum sintering furnace are using the finished product identical sintering process and Ageing Treatment with the neodymium iron boron magnetic body of the present embodiment
Process processing, is then respectively cut into 25mm × 14mm × 1.5mm sheet stocks, 25mm × 14mm × 10mm pieces with inside diameter slicer
Material, obtains the finished product of control group.
Take the finished product of 3 the present embodiment, and 25mm × 14mm × 1.5mm specifications control group and 25mm × 14mm ×
The finished product of the control group of 10mm specifications, carries out magnetism testing, its result is such as using metering institute of China NIM2000 magnetic determining devices
Under：
As can be seen from the test results, the finished product of the neodymium iron boron magnetic body of the present embodiment, its coercivity and magnetic energy product are obvious
Higher than prior art cut after product, while it can also be seen that, prior art make product thickness it is larger when, its coercivity and
Magnetic energy product loss is smaller.
In addition, the material loss amount of the finished product of the present embodiment neodymium iron boron magnetic body only accounts for the finished product quality of neodymium iron boron magnetic body
1.2%, the reason is that the green compact of the finished product are in mechanical processing process, powder is sticked on pipeline and each station.And
For the finished product of control group, the waste of processing 1.5mm processes accounts for the 22% of product quality, processes the waste of 14mm processes
The 5% of product quality is accounted for, the waste of processing 25mm processes accounts for the 6% of product quality.
Meanwhile, also using finished product and warp of the salt spray test to the neodymium iron boron magnetic body of not machined the present embodiment
The finished product of the neodymium iron boron magnetic body of the present embodiment of over mechanical processing carries out decay resistance test.
Specifically, the finished product of the neodymium iron boron magnetic body of 3 the present embodiment is taken, after polishing respectively, 8 μm of zinc layers are plated, together
When, the finished product of the neodymium iron boron magnetic body of 3 the present embodiment is separately taken, 0.2mm is ground off to each surface respectively, then polished, and plates 8
μm zinc layers.
Then, respectively 3 have been plated with not this machined implementation of zinc layers according to GB/T 10125-1997 regulation
The whole production of the neodymium iron boron magnetic body of the present embodiment through over mechanical processing that the finished product of the neodymium iron boron magnetic body of example and 3 have plated zinc layers
Product carry out resistance to neutral salt spray test test, and corrosion-resistant test result is as follows：
It can see by above-mentioned corrosion-resistant test result, surface free is machined the corrosion-resistant of the neodymium iron boron magnetic body of destruction
Performance is improved largely than the neodymium iron boron magnetic body that surface is destroyed through over mechanical processing.
Second embodiment
The present embodiment product to be made is the brshless DC motor magnetic shoe of 39mm × 26mm × 3.5mm specifications, outside it
Arc radius is 62mm, and interior arc radius is 58.5mm, and specific process of the test is as follows：
Neodymium iron boron is weighed with 30wt%Pr-Nd alloys, 2wt%Gd, 0.5wt%Co, 1.1wt%B and 66.4wt%Fe
Raw material, and melting is carried out in vacuum is 0.3-0.8Pa vacuum melting furnace, neodymium iron boron configuration material rejection tablet is prepared, is melted
It is 1500 DEG C to refine temperature；It is again that neodymium iron boron configuration material rejection tablet progress hydrogen is broken, obtain neodymium iron boron configuration coarse powder, here, the broken process of hydrogen
In, desorption temperature is 540 DEG C, and dehydrogenation time is 4.5h.Neodymium iron boron configuration coarse powder is subjected to multiple airflow milling powder again, obtained
The neodymium iron boron configuration powder of 2.5 μm of particle diameters.
It is using rubber pattern that neodymium iron boron configuration powder is tentatively compressing under the conditions of magnetic field orientating, then demagnetize, this
In, the pressure tentatively suppressed is 20MPa；Repressurization carries out isostatic pressed to 600MPa, and green compact are made.
Green compact are taken, under an inert atmosphere, by two faces of self-acting grinding machine milled, and are fixed on flitch, now, green compact
Size is 100mm × 50mm × 28mm；Then, green compact are placed on cutting machine be processed into size for 41.9mm × 28mm ×
4.2mm × R62mm arcuation blank material.Again through chamfer polishing, be put into sintering magazine, with the graphite cake of the corresponding radian of surface band or
Other ceramic wafers do bedding and padding, are fitted into together in vacuum sintering furnace；Vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, then
To being warming up to 500 DEG C in vacuum sintering furnace stove, 2h is incubated；Then, then 1080 DEG C will be warming up in vacuum sintering furnace stove, insulation
4h, is subsequently cooled to room temperature, completes sintering step.
Then, the neodymium iron boron magnetic body for completing sintering step is taken out, the neodymium iron boron magnetic body is fixed using fixture, and apply external force
Compress, and place into vacuum sintering furnace, and the vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, then heat to
900 DEG C, and 2h is incubated, complete first time Ageing Treatment；Afterwards, argon gas is filled with into vacuum sintering furnace again, makes vacuum-sintering
310 DEG C are quickly cooled in stove, stops cooling, and the vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, is then heated to
550 DEG C, and 2h is incubated, complete second of Ageing Treatment.Finally, argon gas is filled with into vacuum sintering furnace, makes vacuum sintering furnace stove
Inside be cooled to room temperature, thus obtain size for (39mm ± 0.08mm) × (26mm ± 0.05mm) × (3.5mm ± 0.035mm) ×
R62mm arcuation body, is then polished to the arcuation body, and electroplates the neodymium-iron-boron that 10 μm of ambrose alloy nickel obtains the present embodiment
The finished product of body.
The another green compact for taking 100mm × 50mm × 28mm specifications are put into sintering magazine, are buried with ceramic powders, and fill together
Enter in vacuum sintering furnace；Green compact in vacuum sintering furnace use the finished product identical with the neodymium iron boron magnetic body of the present embodiment to burn
Knot process and ageing process processing, then cut into inside diameter slicer and WEDM 39mm × 26mm ×
3.5mm × R62mm arcuation product, through chamfering and polishing, and electroplates the finished product that 10 μm of ambrose alloy nickel obtains control group.
In whole manufacturing process, the material loss amount of the finished product of the present embodiment neodymium iron boron magnetic body only accounts for neodymium iron boron magnetic body
Finished product quality 3%, the reason is that the finished product is when burning till contraction, the size on 39mm directions is marked beyond delivery
Accurate (39mm ± 0.05mm), it is necessary to grind processing with two-sided mill, meanwhile, the green compact of the finished product are in mechanical processing process, powder
End is sticked on pipeline and each station.And for the finished product of control group, the finished product of control group is in mechanical processing process
Waste accounts for the 35% of product quality.
Meanwhile, also the finished product of the neodymium iron boron magnetic body of the present embodiment and the finished product of control group are entered using salt spray test
Row decay resistance is tested.
Specifically, according to the GB/T 10125-1997 finished product for providing neodymium iron boron magnetic body respectively to 3 the present embodiment
Resistance to neutral salt spray test test is carried out with the finished product of control group, corrosion-resistant test result is as follows：
It can see by above-mentioned corrosion-resistant test result, surface free is machined the corrosion-resistant of the neodymium iron boron magnetic body of destruction
Performance is improved largely than the neodymium iron boron magnetic body that surface is destroyed through over mechanical processing.
3rd embodiment
With 29wt%Pr-Nd alloys, 1.5wt%Dy, 0.5wt%Co, 1.0wt%Al, 0.2wt%Cu, 0.9wt%B with
And 66.9wt%Fe weighs neodymium iron boron raw material, and melting is carried out in vacuum is 0.3-0.8Pa vacuum melting furnace, be prepared into
To neodymium iron boron configuration material rejection tablet, here, smelting temperature is 1500 DEG C；It is again that neodymium iron boron configuration material rejection tablet progress hydrogen is broken, obtain neodymium
Iron boron configures coarse powder, here, during hydrogen is broken, and desorption temperature is 540 DEG C, and dehydrogenation time is 4.5h.Neodymium iron boron is configured thick again
Powder carries out multiple airflow milling powder, obtains the neodymium iron boron configuration powder of 3 μm of particle diameters.
It is using die that neodymium iron boron configuration powder is tentatively compressing under the conditions of magnetic field orientating, here, tentatively suppress
Pressure is 20MPa；Then demagnetize, repressurization to 200MPa carries out isostatic pressed, and the green compact of Φ 12mm × 40mm specifications are made.
Green compact are taken, green compact are placed on to the round sheet for being processed into that size is Φ 12mm × 1mm on cutting machine under protection oil
Blank material.Again through chamfer polishing, it is put into sintering magazine, lies on graphite or ceramic backing, be fitted into together in vacuum sintering furnace；
Vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, then to being warming up to 500 DEG C in vacuum sintering furnace stove, is incubated 2h；So
Afterwards, it then will be warming up to 1070 DEG C in vacuum sintering furnace stove, be incubated 4h, 100 DEG C are cooled to afterwards, comes out of the stove and completes sintering step.
Then, base substrate after sintering is kept flat to backing plate on loading vacuum sintering furnace, every layer of base substrate plus smooth, 10 layers of pad again
Stainless steel plate is added to apply pressure on plate.Vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, 900 DEG C are then heated to, and
2h is incubated, first time Ageing Treatment and shaping is completed；Afterwards, argon gas is filled with into vacuum sintering furnace again, makes vacuum sintering furnace
300 DEG C are inside quickly cooled to, stops cooling, and the vacuum in vacuum sintering furnace is evacuated to less than 0.2Pa, is then heated to
550 DEG C, and 2h is incubated, complete second of Ageing Treatment.Finally, argon gas is filled with into vacuum sintering furnace, makes vacuum sintering furnace stove
Room temperature is inside cooled to, so as to obtain the neodymium iron boron magnetic body finished product that size is Φ 12mm × 1mm.
The another green compact for taking size to be Φ 12mm × 40mm specifications are put into sintering magazine, are fitted into together in vacuum sintering furnace；
Green compact in vacuum sintering furnace use with the finished product identical sintering process and timeliness of the neodymium iron boron magnetic body of the present embodiment
Reason process, it is then cylindrical to 12mm with less grinder for grinding, and Φ 12mm × 1mm sheet stocks are cut into inside diameter slicer, obtain
The finished product of control group.
The material loss amount of the finished product of the present embodiment neodymium iron boron magnetic body only accounts for the finished product quality of neodymium iron boron magnetic body
3%.And for the finished product of control group, the waste of the finished product of control group in mechanical processing process accounts for product quality
37%, wherein, peripheral milling waste accounts for the 10% of product quality, and the waste of cutting process accounts for the 27% of product quality.This
Outside, the pressure that the present embodiment is used when suppressing green compact is only 200MPa, so, is processed in the green compact to the present embodiment
When, breakage rate is larger, and this can influence the production efficiency of product；Therefore, applicant does not recommend the technical side using the present embodiment
Case, the present embodiment is only that when proving that the pressure for suppressing green compact uses 200MPa, can also realize the making of the neodymium iron boron of the present invention
Method.
It should be appreciated that for those of ordinary skills, can according to the above description be improved or converted,
And all these modifications and variations should all belong to the protection domain of appended claims of the present invention.
Claims (10)
1. a kind of preparation method of neodymium iron boron magnetic body, it is characterised in that comprise the following steps：
Step S1, prepare neodymium iron boron configuration powder；
Step S2, under the conditions of magnetic field orientating neodymium iron boron configured into powder pressing into primary billet；Then demagnetize, and
Primary billet is pressed into green compact under 600MPa-1500MPa pressure；The green compact are machined into neodymium iron boron magnetic body finished product again
Shape；
Step S3, will be machined after green sintering into neodymium iron boron magnetic body finished product.
2. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that the step S1 includes：
29-35wt%R, 0-4wt%M, 0.9-1.1wt%B and 59.9-70.1wt%Fe are weighed, and is mixed；Here, R is
One or more in La, Ce, Pr, Nd, Gd, Ho, Tb and Dy；M is the one or more in Co, Al, Cu, Zr, Ga, Nb；
The neodymium iron boron raw material of mixing is quick-fried or direct powder processed obtains neodymium iron boron configuration powder by hydrogen through vacuum melting, ingot casting or after getting rid of band.
3. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that in step s 2, machining
Process includes one or more of cutting, grinding, peripheral milling, drilling and digging step.
4. the preparation method of the neodymium iron boron magnetic body according to claim 1-3 any one, it is characterised in that be machined
Journey is carried out in inert atmosphere or protection oil.
5. the preparation method of neodymium iron boron magnetic body according to claim 4, it is characterised in that produced by mechanical processing process
Break flour after filtering, be mixed into neodymium iron boron configuration powder in；Rim charge produced by mechanical processing process is mixed into neodymium after crushed
In iron boron configuration powder.
6. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that in step s3, adds through machinery
Green compact clamping after work is put into magazine on fixture, is then placed in vacuum sintering furnace and is sintered together；Or
Using green compact of the powder burial do not reacted with green compact after machined, and sintering in vacuum sintering furnace is placed on together.
7. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that by polylith it is machined after
Green layer lamination is tight, and pad is lined between green compact, is then put into vacuum sintering furnace and sinters together.
8. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that step S3 also includes：
The neodymium iron boron magnetic body fixed using fixture after the completion of sintering, and apply external force compression, and together at 300 DEG C -1200 DEG C
It is incubated more than 20min；Then more than 20min is incubated at 300 DEG C -700 DEG C, makes the shape of neodymium iron boron magnetic body and the shape of fixture
Match, neodymium iron boron magnetic body is finally cooled to room temperature, obtain the finished product of neodymium iron boron magnetic body.
9. the preparation method of neodymium iron boron magnetic body according to claim 8, it is characterised in that the fixture be flat-bottom structure,
Concave-convex curved surface structure or hollow support rod structure.
10. the preparation method of neodymium iron boron magnetic body according to claim 1, it is characterised in that in step s3, by reducing agent
It is put into together with the green compact after machined in vacuum sintering furnace；The reducing agent include calcium metal, magnesium metal, metallic sodium,
One or more in calcium hydride, magnesium hydride and sodium hydride.
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| CN201610081348.7A CN105741994B (en) | 2016-02-04 | 2016-02-04 | A kind of preparation method of neodymium iron boron magnetic body |
| PCT/CN2017/072550 WO2017133609A1 (en) | 2016-02-04 | 2017-01-25 | Manufacturing method for neodymium-iron-boron magnet |
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| CN201610081348.7A CN105741994B (en) | 2016-02-04 | 2016-02-04 | A kind of preparation method of neodymium iron boron magnetic body |
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| CN105741994B (en) * | 2016-02-04 | 2017-09-01 | 李忠 | A kind of preparation method of neodymium iron boron magnetic body |
| CN106826292B (en) * | 2017-03-17 | 2019-05-10 | 东阳市横店友联磁业有限公司 | Road processes slice process process after magnet steel cutting clamper and neodymium iron boron |
| CN108538562B (en) * | 2018-03-05 | 2020-04-21 | 杭州电子科技大学 | Method for manufacturing magnetic shielding sheet of wireless receiving end |
| CN108831657B (en) * | 2018-08-16 | 2023-10-24 | 烟台首钢磁性材料股份有限公司 | Method and special device for improving performance of sintered NdFeB magnet |
| CN109676129A (en) * | 2018-12-17 | 2019-04-26 | 浙江东阳东磁稀土有限公司 | A kind of neodymium-iron-boron preparation of high stock utilization |
| CN109712797B (en) * | 2019-01-03 | 2021-06-18 | 浙江东阳东磁稀土有限公司 | Method for improving grain boundary diffusion magnetic property consistency of neodymium iron boron magnet |
| CN109961915A (en) * | 2019-03-05 | 2019-07-02 | 宁波金科磁业有限公司 | A kind of magnetic sheet forming method |
| CN109903986A (en) * | 2019-04-01 | 2019-06-18 | 中钢集团南京新材料研究院有限公司 | A kind of coercitive method of raising neodymium iron boron magnetic body |
| CN110202324B (en) * | 2019-06-05 | 2021-03-12 | 浙江鑫盛永磁科技有限公司 | Process for manufacturing neodymium-iron-boron magnet |
| CN114709066A (en) * | 2022-04-15 | 2022-07-05 | 中钢天源股份有限公司 | Method for manufacturing permanent magnetic ferrite thin-wall magnetic shoe |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10241981A (en) * | 1997-02-28 | 1998-09-11 | Hitachi Metals Ltd | Manufacture of rare earth metal permanent magnet and rare earth metal permanent magnet |
| CN102568738A (en) * | 2012-02-18 | 2012-07-11 | 西安西工大思强科技有限公司 | Manufacturing method of high-mechanical-strength sintered neodymium iron boron permanent magnets |
| CN104907558A (en) * | 2015-06-28 | 2015-09-16 | 浙江康盈磁业有限公司 | A rare earth permanent magnetic material preparing method |
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| CN101562067A (en) * | 2008-04-18 | 2009-10-21 | 沈阳中北通磁科技有限公司 | Manufacture method of corrosion-resistant R-Fe-B rare-earth permanent magnet |
| CN103878368A (en) * | 2012-12-19 | 2014-06-25 | 吴庆华 | Technology and device for forming dry bag quick isostatic pressing in oriented magnetic fields |
| CN105741994B (en) * | 2016-02-04 | 2017-09-01 | 李忠 | A kind of preparation method of neodymium iron boron magnetic body |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10241981A (en) * | 1997-02-28 | 1998-09-11 | Hitachi Metals Ltd | Manufacture of rare earth metal permanent magnet and rare earth metal permanent magnet |
| CN102568738A (en) * | 2012-02-18 | 2012-07-11 | 西安西工大思强科技有限公司 | Manufacturing method of high-mechanical-strength sintered neodymium iron boron permanent magnets |
| CN104907558A (en) * | 2015-06-28 | 2015-09-16 | 浙江康盈磁业有限公司 | A rare earth permanent magnetic material preparing method |
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