CN1269587A - Magnetic regeneration process for the waste material from the production of transition rare earth permanent-magnet and its product - Google Patents
Magnetic regeneration process for the waste material from the production of transition rare earth permanent-magnet and its product Download PDFInfo
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- CN1269587A CN1269587A CN 99103590 CN99103590A CN1269587A CN 1269587 A CN1269587 A CN 1269587A CN 99103590 CN99103590 CN 99103590 CN 99103590 A CN99103590 A CN 99103590A CN 1269587 A CN1269587 A CN 1269587A
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Abstract
The present invention relates to a magnetic regeneration method of waste material produced in production of rare earth transition permanent magnet and its product. Said method includes the following steps: cleaning waste materials of the first generation, second generation and third generation magnets of rare earth permanent magnet, making powder, respectively adding new material, finding proper proportion, according to said proportion charging or making correspondent intermediate phase richly containing rare earth, adding waste material, smelting to obtain mixed powder, forming in magnetic field, sintering, ageing and magnetizing to obtain the invented magnetic product.
Description
The present invention relates to permanent magnet, particularly relate to the transition rare earth permanent magnet, as the rare earth cobalt-based, waste material magnetic regeneration process and products thereof during rare-earth iron-based permanent magnet is produced.
In society, permanent magnetic material is crucial a kind of functional material, and it is widely used among electronics industry, electric, electroacoustic apparatus, motor, the magnetic machinery.In industry, agricultural, traffic, national defence, each field, used widely.Between rare-earth transiting group metal in the compound, RCO
5, R (Co, Cu, Fe, Zr)
z, R11.76+xFe82.36-x-yB5.88+yO
2(R-represents rare earth element, and M represents Zr, Hf, Ti, elements such as Ni) three series are represented the first generation, the second generation, third generation rare earth permanent magnet respectively.Its production method mainly adopts the powder metallurgy method, but the metal casting yield is 60-65% only in producing, and produces some waste materials in the production, and these waste materials comprise leftover pieces remaining in underproof magnet of magnetic or the processing etc.Because this waste magnet accounts for significant proportion in producing, and has influenced the economic benefit of factory, has reduced labor productivity.
The objective of the invention is to propose a kind of method that makes the waste material magnetic regeneration of producing permanent magnet or permanent magnetic material, make RCo in the rare-earth transition metal compound
5, R (Co, Cu, Fe, M)
z, R
11.76+xFe82.36-x-yB5.88+yO
2The magnetic of waste material regeneration during (R-represents rare earth element, and M represents Zr, Hf, Ti, elements such as Ni) three class permanent magnets are produced, the metal casting yield is improved.
The objective of the invention is to realize by following technology:
One, the step of manufacture method: after alloy prepares, pack into the alloy powder process of vacuum induction furnace melting, melting, through coarse crushing, in the 2.5-7 μ m that reaches broken, in small, broken bits, powder is moulding in magnetic field, the blank that molded blank is packed into after sintering in the vacuum sintering furnace (heat-treatment furnace), timeliness, the timeliness enters machining, magnetization detects, and becomes product.
Two, alloy formula
1.R1-xCO
5-y(R＝Sm，Pr，Er，Ho)x＝0.9-0?y＝0.1-0.5
2.R(Co?Cu?Fe?M)
z
R represents Sm, and Pr M represents Zr, Hf, Ti, element Z=6.9-8.7 such as Ni.
3.R11.76+xFe82.36-x-yB5.88+y.O
2
R is Nd, Pr, Dy, Tb, Ho, Er; Partly quilt column element replacement down of Fe: Nb, Ta, V, Ti, Zr, Mo, Ga, W, Cr, O
2Be O
2, N
2, N
2, H
2
The present invention is by adding Er, and Ho improves the temperature coefficient of magnet, by adding the coercive force of Nb Ta, Ga, Co, Al raising alloy.By interpolation V, Nb, Er, Ti, MO, W, Cr improve the thermal stability of alloy, corrosion resistance, the serviceability temperature of raising alloy.
Oxygen enters formation Sm in the technical process of preparation magnet
2O
3, NdFe
2O
yPhase, NdFe
2O
yPhase, y=0.2-0.4 is present in R
2F
14B, (Nd, Dy)
2Fe
14-aMaB and Nd
1+eFe
4B
4Intergranular.Sintering R-Fe-B-O-M magnet mainly contains following phase composition: R
2Fe
14B, (Nd, Dy)
2Fe14-aMaB.SmCO
5The master has Sm mutually
2CO
7And Sm
2Co
17 phases.Nd
1+eFe
4B
4Be boron-rich phase, Nd
2Fe
14B is the matrix phase of tetragonal structure.Also has rich Nd phase in addition.
The prescription of waste magnet magnetic regeneration:
1.RCo
5System, RCo
5-x(R=Sm, Pr), X=0-4,
2.R (Co, Cu, Fe, M)
z, R=Sm wherein, M represents Zr, Hf, Ti, elements such as Ni, Z=6.9-8.7,
3.Nd-Fe-B be Nd
16-xFe
2By
X=0.1-2 wherein, Z=1-82, the y=5.6-11 waste magnet must clean up the appearance oxide layer when reclaiming with organic solvent, magnetic waste material is entered the heat demagnetization to be handled, be equipped with the virgin material by above-mentioned prescription melting powder process again, powder process is to the 3-6 micron, moulding in magnetic field, the blank sintering heat treatment in the vacuum heat treatment furnace of packing into after the moulding.Its temperature schedule is respectively:
1.RCo
5Under vacuum or argon shield, 1115-1125 ℃, sintering 1-4 hour, be chilled to 900 ℃ with the speed of 0.5-0.9 ℃/min, be incubated 1-10 hour speed and be chilled to room temperature with 140-160 ℃/min.
2.R (Co, Cu, Fe, M)
z, under vacuum or argon shield, between 1125-1180 ℃, solution time 0.5-11 hour.The solution treatment purpose is the single-phase solid solution that will obtain uniformity.Adopt in quenching or the Ar gas magnetic afterwards and cool off.General 720-900 ℃, the isothermal aging time is with 15 assign to-50 minutes (Zr≤1.5at%) and 7-32 hour (Zr＞2.0at%), can adopt interrupted aging or control cooling behind the isothermal aging.Owing to contain Zr, adopt interrupted aging for this alloy, the temperature and time of interrupted aging can adopt 650-750 ℃ and 550-650 ℃, be respectively 1 hour, and 450 ℃-550 ℃, 2 hours, 350 ℃-450 ℃, 3.5-4.5 hour, 250 °-350 ℃, 7-11 hour.The about 0.25-1.8% of control cooling rate/℃.Reduce to room temperature.
3.Nd-Fe-B be, under vacuum or nitrogen protection, 1106-1130 ℃ of sintering is incubated 1-3 hour, 850-950 ℃ is incubated 0.5-2 hour, at 500-650 ℃ of insulation 0.5-5 hour, cool to room temperature.
The size that customer requirements is pressed in back processing is carried out ground-parallel, coats Zn or the anti-oxidation of Ni according to user's needs surface, whether magnetizes also according to the need of using.
This product is limited in the 100-12000PPM scope with oxygen, and waste magnet magnetic reconstituted product oxygen is limited in 100-7500PPM.
Come to divide to be divided into from method and add 1. mutually that prescription is Nd100-xFe
xB
8(x=20-80), interpolation phase and waste material mixing are processed by above-mentioned technology, 2. waste material is returned and mixingly in the smelting furnace of making new magnetic material be crushed to the 2.6-6.5 micron after 8. waste magnet being cleaned after heat demagnetization by above-mentioned explained hereafter again, be equipped with new material powder, the method is every batch will do the mixing ratio experiment, which kind of ratio the best? the most suitable user of magnet who produces is required to be the best, can prepare the permanent magnet product of the needed various trades mark of user with the method.
Below with non-limiting examples more specifically, describe the present invention in detail, will help understanding to the present invention and advantage thereof, protection scope of the present invention is not subjected to the qualification of these embodiment, protection scope of the present invention is decided by claims.
Embodiment 1
SmCo
5: 16.56at%Sm, 83.44at%Co, alloy melting in intermediate frequency furnace (Ar gas shiled) is cast into ingot in water cooled mo(u)ld, at N
2Powder process is to 4-5.3 μ m under the gas shiled.Get SmCo
5Waste magnet, after the cleaning, the heat demagnetization is at N
2Under the gas shiled, powder process is added to the waste material different proportion with virgin material to 4-5.3 μ m, finds out after the optimal proportion, and this batch waste material prescription draws at N
2Under the gas shiled under 12000 gauss magnetic fields, at 2 tons/cm
2Forming under the pressure, blank sintering in heat-treatment furnace after the moulding, 1120 ℃ of insulations 1.5 hours are chilled to 900 ℃ with the speed of 0.7 ℃/min, are incubated 1 hour, and the speed with 60 ℃/min is chilled to room temperature again.Measure Br=0.97T, iHc=1992KA/m, (BH)
Max=171.2Kj/m
3
Example 2
The Nd13.2Dyo.1Fe79.9B6.2Nb0.3Ga0.09Al0.2Cu0.01 alloy, melting in intermediate frequency furnace (Ar gas shiled) is cast into ingot, at N in water cooled mo(u)ld
2Powder process is to 4-5 μ m under the gas shiled.Waste magnet, after cleaning at N
2Powder process under the gas shiled; with new material to the waste magnet material with 10%, 20%, 30%; 40%; 50%, 90% ratio mixing is at magnetic field protection compacted under; blank sintering 2 hours under 1120 ℃ of vacuum conditions after the moulding; drop to room temperature 630 ℃ of insulations after 1 hour, the back adds magnetic measurement and finds out which ratio magnetic property height, decides.This batch waste material is prepared burden with this ratio, greater than 12000 gauss magnetic field compacted unders, blank after the moulding is packed in the heat treatment, 1118 ℃ of vacuum-sinterings 2 hours, 900 ℃ of insulations 2 hours, drop to 630 ℃ of insulations 1 again, 5 hours, drop to room temperature and come out of the stove, grind processing, under 21000 Gauss's magnetic, magnetize sample in measurement.
Claims (10)
1. a method of producing permanent magnetic material is characterized in that comprising the following steps:
This rare earth permanent-magnetic material comprises with following three classes: (1), RCO
5System, prescription R
1-xCo
5-y, R=Sm wherein, Pr, Er, Ho; X=0.9-0; Y=0.1-0.5 has CaCu
5The type structure.Belong to hexagonal crystal system.(2), R (Co Cu Fe M) Z system, M represents elements such as Zr Hf Ti Ni, and wherein R represents Sm, Pr, Er, Ho, Z=6.9-8.7 at high temperature all has Th
2Ni
17The crystal structure of type will change Th at low temperatures
2Zn17 type structure.Belong to hexagonal crystal system, i.e. 2:17 type R-Co compound.(3), R-Fe-B system, R
2Fe
14B is that main body is the magnetic phase mutually, adds non magnetic mutually rich Nd phase and Nd
1+eFe
4B
4Rich B mutually and phase composition.This material contains 90% or the R of more tetragonal
2Fe
14The B principal phase, (R=Nd, Pr, Dy, Tb, Gd), the incommensurable Nd of a spot of one dimension
1+eFe
4B
4(e=0.1-0.3) the rich Nd of boron-rich phase and center of area master side mutually.Rich Nd has two hexagonal structures mutually, and the rich Nd of thin layer has the center of area (FCC) structure mutually.Its composition 75at%, 25%Fe.If rich Nd phase constituent is by Fe: the Nd ratio can be divided into 1: 1.2-1.4,1: 20-2,30,1: 3.5-4.5, the rich Nd phase of 1: 7 four kinds of composition.Raw material after the formulated of this three class, alloy is good is smelted into alloy pig through intermediate frequency furnace, powder process, and moulding in magnetic field, sintering, timeliness are reduced to room temperature, magnetization, promptly get the different magnets of three classes.After the waste material cleaning, at N
2Powder process under the gas shiled, different system waste materials mix the above-mentioned three kinds virgin material of variety classes, make proportioning test earlier; find after the ratio, this batch waste material is a prescription with this ratio just, prepares material; mix, moulding in magnetic field, sintering, timeliness, magnetization promptly obtain permanent-magnet alloy.Waste recovery another kind method is the middle phase of the rich R of melting, be assigned in the waste magnet in varing proportions, promptly obtain finished product through powder process moulding in magnetic field, sintering, timeliness, magnetization, the third makes the waste magnet magnetic regeneration process is after waste magnet is cleaned, mix melting in intermediate frequency furnace together in the virgin material slightly, powder process, moulding in magnetic field, sintering, timeliness, processing, magnetization.
2. according to the described permanent magnet of claim 1, a kind of of its feature is RCO
5System, R=y, Sm, several compounds of Ce, La all have each quite high magnetropism, and the C axle is easy magnetizing axis, wherein Sm-CO
5Has maximum magnetic respectively to class.Press SmCO
5, SmCO
5-x, PrCO
5-x(X=0.1-0.5) prepare after the material after molten alloy fusing under the Ar gas shiled, the alloyed powder powder process of cast is at N
2Gas descends or preserves in organic medias such as toluene gasoline.With RCO
5Be after waste magnet cleans; powder process; virgin material and waste magnet material all are ground to 4-5.3 μ m (under media protection); shaping blank entered heat-treatment furnace at 1110-1130 ℃ of sintering 1-4 hour in magnetic field; be chilled to 850-950 ℃ of insulation 1-10 hour with the speed of 0.5-0.9 ℃/min, then with the speed cool to room temperature of 140-160 ℃/min.The magnetic property that mill is cut, in-process measurement obtains.
3. according to a kind of of its feature of the described permanent magnet of claim 1 be: R (Co Cu FeMe)
z, on behalf of rare earth element M, R represent Zr, hf, Ti, elements such as Ni, promptly Sm (Co, Cu, Fe, M) the Z alloy has 2: 17 phases, 1: 5 phase, Co mutually and liquid phase.Z value 6.9-8.7.Cu is 0.05～0.09, between, Fe is between 0.04-0.31, and M is between 0.009-0.04.Sm
Z-xHR
XCo
cU
VFr
WM
QAlloy, x=0.3-0.9, HR represents heavy rare earth, ER, Ho, Gd, Q U are between 9-11, and V is between 1.3-16, and W is between 3.0-3.4, and Q is between 0.18-0.21.The raw material of the above-mentioned prescription composition vacuum induction melting of packing into, alloy pig powder process system 4-7.5 μ m, the R-Co waste magnet cleaning of 2:17 type is clean, and heat demagnetization, powder process are to 4-7.5 μ m, the above-mentioned batching alloyed powder of newly getting mixes by a certain percentage and finds out optimal proportion, prepares in this ratio.At 0.5-4T/cm
2Press in, the magnetic field orientating moulding was 1120-1235 ℃ of temperature range sintering 1-4 hour, 810-920 ℃ of isothermal aging 11-16 is little, 790-810 ℃ of timeliness 30min, and 590-610 ℃ of timeliness 2 hours are arrived in slow cooling, slow cooling promptly obtains high-performance permanent magnet to 390-410 ℃ again.
4. according to the described permanent magnet of claim 1, a kind of of its feature is: press Nd11.76+XFe82.36-X-yB
5.88+yO
2The alloyage composition, (X=0～3.6, y=0～2.3L) wherein Fe can be replaced by Co, Al.Ta-Nb.Ga, one or more elements of W, Mo.V.Cr.The raw material of the above-mentioned prescription composition vacuum induction melting of packing into, alloy pig powder process are after waste magnet cleans to 2.8-6.5 μ m with Nd-Fe-B, heat demagnetization powder process is to 2.8-6.5 μ m, above-mentioned new batching alloyed powder mixes by a certain percentage, finds out optimal proportion, prepares in this ratio.At 0.5-4T/cm
2Press in add the above magnetic field of 1.2T when moulding, moulding, blank is in 1080-1135 ℃ of temperature range sintering 1-4 hour after the moulding, at 850-950 ℃ of isothermal aging 0.5-2 hour, at 560-670 ℃ of timeliness 1-4 hour, cool to room temperature.Mill processing, magnetization, measurement.
5. according to the described permanent magnet of claim 1, one of its feature is that oxygen content is at 1000-12000ppm in the rare-earth permanent magnet.
6. according to claim 1 and the described permanent magnet of claim 4, one of its feature is: Fe can be replaced by at least a M element in the R-Fe-B permanent magnet, and its alternative amount must not be greater than following setting:
6at％AL，50at％Co，7at％Nb，8.2at％Ta，8.3at％V，
10at％Er，5.8at％Ti，6.6at％Ga，9.6at％Mo，8at％W
7. according to the described permanent magnet of claim 1, one of its feature is: in the sintering process, under vacuum condition, can be warmed up to sintering temperature soon, but must bleed off the waste gas of discharging in the blank.
8. according to the described permanent magnet of claim 1, it is characterized in that: RCO
5Class is made SmCO
x(x=1-4) middle phase, and RCO
5Two kinds of excellent powder proportionings of performance are found out in respectively powder process of waste magnet, moulding in magnetic field, sintering timeliness, magnetization or with this waste material Returning smelting stove and virgin material melting together, powder process, moulding, sintering, magnetization.
9. according to the described permanent magnet of claim 1, it is characterized in that: Sm (Co Cu FeM)
z(R represents rare earth, and Z is from 6.8-8.5) makes Sm (Co Cu Fe Er)
z(Z=2-7) middle phase, and R (Co Cu Fe Er)
zTwo kinds of excellent proportionings of performance are found out in the respectively powder process of waste magnet system, moulding in magnetic field, sintering, timeliness, magnetization or with melting in this waste material Returning smelting stove, powder process, moulding, sintering, magnetization.
10. according to the described permanent magnet of claim 1, it is characterized in that: Nd11.76+xFe82.36-x-yB5.88+yO
2(x=3-90, y=2-7) make in the middle of mutually and Nd-Fe-B class waste magnet distinguish powder process, find out two kinds of excellent proportionings of performance, moulding in magnetic field, sintering, timeliness, magnetization or with melting in this waste material Returning smelting stove, powder process, sintering, magnetization.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 99103590 CN1269587A (en) | 1999-04-05 | 1999-04-05 | Magnetic regeneration process for the waste material from the production of transition rare earth permanent-magnet and its product |
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|---|---|---|---|
| CN 99103590 CN1269587A (en) | 1999-04-05 | 1999-04-05 | Magnetic regeneration process for the waste material from the production of transition rare earth permanent-magnet and its product |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1275741A1 (en) * | 2001-07-10 | 2003-01-15 | Shin-Etsu Chemical Co., Ltd. | Remelting of rare earth magnet scrap and/or sludge, magnet-forming alloy, and sintered rare earth magnet |
| CN100518967C (en) * | 2006-12-08 | 2009-07-29 | 四川川西磁业有限责任公司 | Method for reutilizing waste and inferior material and grinding abrasive in magnetic material production process |
| CN102101120A (en) * | 2009-12-21 | 2011-06-22 | 上海爱普生磁性器件有限公司 | Method for recycling boned neodymium iron boron permanent magnet defective product |
| RU2446497C1 (en) * | 2008-02-20 | 2012-03-27 | Улвак, Инк. | Method of processing waste magnets |
| CN103390478A (en) * | 2013-08-08 | 2013-11-13 | 内蒙古科技大学 | Method for recovering neodymium iron boron powder waste and method for preparing permanent magnet material by using neodymium iron boron powder material |
| CN105261474A (en) * | 2015-11-13 | 2016-01-20 | 绵阳德华磁材有限公司 | Method for recycling samarium-cobalt permanent magnet material waste |
| CN107316726A (en) * | 2017-07-14 | 2017-11-03 | 钢铁研究总院 | A kind of preparation method of sintered samarium cobalt magnet |
| CN113436818A (en) * | 2021-06-24 | 2021-09-24 | 北京航空航天大学 | Rare earth-based material capable of spontaneously forming topological magnetic domain structure and preparation method thereof |
-
1999
- 1999-04-05 CN CN 99103590 patent/CN1269587A/en active Pending
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1275741A1 (en) * | 2001-07-10 | 2003-01-15 | Shin-Etsu Chemical Co., Ltd. | Remelting of rare earth magnet scrap and/or sludge, magnet-forming alloy, and sintered rare earth magnet |
| CN100518967C (en) * | 2006-12-08 | 2009-07-29 | 四川川西磁业有限责任公司 | Method for reutilizing waste and inferior material and grinding abrasive in magnetic material production process |
| RU2446497C1 (en) * | 2008-02-20 | 2012-03-27 | Улвак, Инк. | Method of processing waste magnets |
| CN102101120A (en) * | 2009-12-21 | 2011-06-22 | 上海爱普生磁性器件有限公司 | Method for recycling boned neodymium iron boron permanent magnet defective product |
| CN103390478A (en) * | 2013-08-08 | 2013-11-13 | 内蒙古科技大学 | Method for recovering neodymium iron boron powder waste and method for preparing permanent magnet material by using neodymium iron boron powder material |
| CN103390478B (en) * | 2013-08-08 | 2016-04-13 | 内蒙古科技大学 | Reclaim the method for neodymium iron boron powder scrap and utilize it to prepare the method for permanent magnetic material |
| CN105261474A (en) * | 2015-11-13 | 2016-01-20 | 绵阳德华磁材有限公司 | Method for recycling samarium-cobalt permanent magnet material waste |
| CN107316726A (en) * | 2017-07-14 | 2017-11-03 | 钢铁研究总院 | A kind of preparation method of sintered samarium cobalt magnet |
| CN107316726B (en) * | 2017-07-14 | 2019-01-15 | 钢铁研究总院 | A kind of preparation method of sintered samarium cobalt magnet |
| CN113436818A (en) * | 2021-06-24 | 2021-09-24 | 北京航空航天大学 | Rare earth-based material capable of spontaneously forming topological magnetic domain structure and preparation method thereof |
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