CN104036947A - Method for manufacturing high-coercivity regenerated sintered neodymium-iron-boron magnet by waste permanent-magnet motor magnet steel - Google Patents

Method for manufacturing high-coercivity regenerated sintered neodymium-iron-boron magnet by waste permanent-magnet motor magnet steel Download PDF

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CN104036947A
CN104036947A CN201410258657.8A CN201410258657A CN104036947A CN 104036947 A CN104036947 A CN 104036947A CN 201410258657 A CN201410258657 A CN 201410258657A CN 104036947 A CN104036947 A CN 104036947A
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waste
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岳明
刘卫强
季维骁
李超
张东涛
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Beijing University of Technology
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Abstract

The invention relates to a method for manufacturing a high-coercivity regenerated sintered neodymium-iron-boron magnet by waste permanent-magnet motor magnet steel and belongs to the technical field of magnetic materials. The high-coercivity regenerated sintered neodymium-iron-boron magnet is manufactured by regenerating waste rare-earth permanent-magnet motor magnet steel by means of the rare-earth hydrogenated dysprosium nanopowder doping technique. The method includes the steps of preparing NdFeB powder by means of hydrogen explosion and jet milling techniques; preparing hydrogenated dysprosium nanopowder by means of the physical vapor deposition technique; mixing the two powders, and subjecting mixture to magnetic field orientation and pressing; subjecting compacts to dehydrogenation, sintering and heat treatment at different temperatures to obtain the sintered magnet. The coercivity of the regenerated magnet manufactured by the method is higher than that of the original magnet steel, and remanence and magnetic energy product are approximate to those of the original magnet steel. The method has the advantages that the process is short, cost and energy consumption are low, and resources are saved.

Description

A kind of method of utilizing waste and old magnetic steel of magnetoelectric machine to prepare high-coercive force regeneration Sintered NdFeB magnet
Technical field
The present invention relates to a kind of to disassemble waste and old magneto magnet as primary raw material, utilize the nano-particle doped sintered method of hydrogenation dysprosium to prepare the new technology of high-coercive force regeneration Sintered NdFeB magnet, the present invention can realize the high-valued recycling of waste and old rare-earth permanent-magnet electric machine Nd-Fe-B magnet steel, belongs to technical field of magnetic materials.
Background technology
Recent two decades comes, and along with the fast development of China's economy, rare earth resources reduces increasingly, environmental pollution is on the rise etc., and problem becomes increasingly conspicuous.China's rare earth secondary resource reclaims development space and has a high potential, but less for rare earth resources recycling research work.Wherein neodymium iron boron waste material large for output, that added value is high carries out low value recycling becomes the current most important thing.According to incompletely statistics, by 2010, national waste and old neodymium iron boron yield reached 4.5 ten thousand tons of left and right, caused the reduction greatly of regeneration neodymium iron boron value but lack advanced technology, wasted valuable rare earth resources; Neodymium iron boron greasy filth separate caused serious environmental pollution and rare earth yield low.
The recycling of waste and old rare earth permanent magnet, has not only protected the rare earth strategic resource of China's preciousness, and has protected environment.Pollution itself that avoided waste and old rare-earth products to bring on the one hand; On the other hand, reduce rare earth mineral products resource consumption, greatly alleviated the serious environmental pressure that the adopting of rare earth mineral products, choosing, smelting are brought.As can be seen here; the high-valued recycling of waste and old rare earth permanent magnet not only profit margin is very large; equipment rate is high; there is good economic feasibility; and will greatly reduce Rare Earth Mine yield; containment exhaustive exploitation and the deterioration of the ecological environment, protected China's rare earth resources and biological environment effectively.
Rare-earth permanent-magnet electric machine is one of maximum application market of sintered Nd-Fe-B permanent magnet, a large amount of sintered NdFeB magnet steel has been on active service ten to 20 years, due to the impact of working temperature and external environment, there is reduction in various degree in the performance of magnet steel, therefore the recovery of the Nd-Fe-B magnet steel to rare-earth permanent-magnet electric machine and high-valued recycling work are extremely urgent.But that carries out about the recycling work of rare-earth permanent-magnet electric machine magnet steel at present is less.
Recycle and developed several different methods for sintered NdFeB leftover pieces at present: 1. Extraction of rare earth element and other precious metals from waste and old magnet, this kind of technique exists the rate of recovery low and reclaim the problems such as product purity is low.Dissolution degree that its main cause is to reclaim waste product is low, the precipitation of reaction rare earth not exclusively and the problem such as the separation degree of rare earth elements lnon rare earth elements and multiple rare earth element is poor; Again melting, powder process, die mould, sinter neodymium iron boron magnetic body into, this kind of technological process is longer, takes time and effort; 3. by after broken the explosion of waste and old magnet hydrogen, this kind of technique after the Nd-Fe-B powder identical with appropriate composition mixes, airflow milling refinement, die mould, sinters Nd-Fe-B permanent magnet into, although can reach the object of recovery, but the neodymium iron boron performance of making after mixed powder can reduce, and product price reduces.
On the one hand, said method is not still reaching good effect to the recycling of sintered NdFeB leftover pieces; On the one hand, due to the impact of operating time and environment, the recycling of rare-earth permanent-magnet electric machine magnet steel is more complicated comparatively speaking in addition.Therefore be necessary to go out effective regeneration techniques for rare-earth permanent-magnet electric machine developing magnet.
Directly adopt that hydrogen explosion is broken, ball milling, orientation is compressing, prepared by sintering technology regeneration magnet, it is a kind of regeneration technology of short flow process, but magnet magnetic energy product prepared by this technique has declined 15% than original magnet magnetic energy product, remanent magnetism and coercive force have declined respectively 10% and 20%.In the recycling process of the waste and old magnet of sintered NdFeB, rare earth element can run off, and causes the particularly coercitive significantly reduction of regeneration magnet magnetic property.For the problems referred to above, the performance that how to improve regeneration magnet becomes the key of dealing with problems.Adopt the quick-fried method of hydrogen to be broken into after magnetic at waste and old Sintered NdFeB magnet, by the effectively loss of compensation regeneration Rare Earth Elements in Process of rare earth doped powder.But the quantity of rare earth powder and granularity have vital impact to the magnetic property of regeneration magnet.The quantity of rare earth powder is more, means and generates more rich neodymium phase, and then can obtain larger coercive force; But the increase of non-hard magnetic phase in magnet simultaneously, the remanent magnetism of magnet and maximum magnetic energy product reduce, and can not effectively be replied.The condition of preparing the magnet of high remanent magnetism and high-coercive force is that rich neodymium phase volume fraction is few as much as possible, but main phase grain is by the layer separation completely mutually of thin rich neodymium.Therefore reduce the size of rare earth powder particle, make it in mixed powder process, be coated on main phase grain surface, in sintering process subsequently, realize effective magnetic of main phase grain isolated.Under reaching the isolated precondition of the effective magnetic of main phase grain, if rare earth powder particle is oversize, can cause in magnet rich neodymium phase volume fraction excessive, magnet remanent magnetism and maximum magnetic energy product reduce; If rare earth powder particle is undersized, there will be agglomeration, can cause adverse effect to magnet performance equally.Therefore studying rare earth powder particle size and content is the basis that obtains high-performance regeneration magnet on the impact of regeneration magnet performance.In addition, due to reducing of rare earth doped powder particle size, sintering and the heat treatment optimum temperature of regeneration magnet also can decrease, and what bring is that magnet crystallite dimension reduces thereupon, and then the coercive force of magnet can corresponding raising.
Summary of the invention
The method of preparing high-coercive force regeneration Sintered NdFeB magnet is reclaimed in a kind of hydrogenation dysprosium nano-powder particles doping that the present invention be directed to the above-mentioned state of the art and propose, and reaches that operation is short, energy consumption is low, the object of high efficiente callback.
The present invention for raw material be waste and old rare-earth permanent-magnet electric machine magnet steel, it is characterized in that, comprise the following steps:
(1) the waste and old rare-earth permanent-magnet electric machine magnet steel of removing coating is cleaned and is prepared into the quick-fried powder of neodymium iron boron hydrogen;
The waste and old rare-earth permanent-magnet electric machine magnet steel of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up; Be placed at and in vacuum tube furnace, carry out inhaling hydrogen 3 hours, 600 DEG C, 1 × 10 under 150 DEG C, 0.1MPa hydrogen pressure -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to single crystal grain, obtain NdFeB material powder;
(3) adopt physical gas phase deposition technology to prepare hydrogenation dysprosium powder, its particle diameter is 100-500 nanometer;
(4) the hydrogenation dysprosium nanometer powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is the 2-4% of NdFeB material powder weight, and two kinds of powder are mixed.
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, at 1000-1050 DEG C of sintering 5-7 hour, then carry out secondary heat treatment: wherein first order heat treatment temperature 800-900 DEG C, insulation 4-5 hour; Second level heat treatment temperature 450-500 DEG C, insulation 4-5 hour; The final sintered magnet that obtains.
The feature of this method is:
1. the average grain diameter of the hydrogenation dysprosium particle of the present invention's doping is 100-500 nanometer.Compared with particle doped with the hydrogenation dysprosium that is less than 100 nanometers, more even in the distribution meeting that mixes hydrogenation dysprosium powder particle in powder process, mixed powder effect can be better, finally in sintering process, can make rich neodymium distribute mutually more even, not only effectively repair boundary defect, and can substitute main phase grain Nd 2fe 14the Nd on B border forms has the more Dy of high anisotropy field 2fe 14b, thus increase substantially the coercive force of regeneration magnet, be even greater than the coercive force of original magnet; But Dy 2fe 14the saturation magnetization of B is lower, and therefore too much interpolation can cause the decline of magnet remanent magnetism and magnetic energy product equally.Compared with particle doped with the hydrogenation dysprosium that is greater than 500 nanometers, because hydrogenation dysprosium particle diameter of the present invention is little, reaching on same coercitive basis, required hydrogenation dysprosium content is few, and therefore the remanent magnetism of magnet, magnetic energy product can well be replied simultaneously.
2. compared with conventional sintering technique, sintering temperature and the heat treatment temperature of regeneration sintered magnet are low, therefore can obtain higher coercive force.
3. every magnetic property of the regeneration magnet that prepared by employing the present invention can reach original magnet level, and wherein coercive force can exceed original magnet level, can realize thus high-valued recycling.
4. adopt the inventive method technological process short, cost energy consumption is low, economizes on resources.
Embodiment
Below in conjunction with each embodiment, the present invention will be further described.Right convenient contrast, the magnetic property of original magnetic steel of motor also provides in the lump
Embodiment 1
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 22.5dy 0.8pr 7.1fe 67.8co 0.7cu 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 100 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 2% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1000 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 900 DEG C of first order heat treatment temperatures, are incubated 5 hours; 450 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Comparative example 1-1
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 22.5dy 0.8pr 7.1fe 67.8co 0.7cu 0.1b 1.The waste and old Nd-Fe-B magnet steel of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 10 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 2% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1000 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 900 DEG C of first order heat treatment temperatures, are incubated 5 hours; 450 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Comparative example 1-2
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 22.5dy 0.8pr 7.1fe 67.8co 0.7cu 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopting the quick-fried and ball-milling technology of hydrogen to prepare average grain diameter is the hydrogenation dysprosium powder of 3 microns.
(4) the hydrogenation dysprosium metal micron powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 4% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Comparative example 1-3
(1) waste and old rare-earth permanent-magnet electric machine magnet composition is Nd 22.5dy 0.8pr 7.1fe 67.8co 0.7cu 0.1b 1.Waste and old neodymium iron boron magnet steel is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.On the one hand leftover pieces are placed in vacuum tube furnace, carry out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) neodymium iron boron powder is orientated in 3T magnetic field and compressing;
(4) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Table 1. adopts the particle doped preparation regeneration sintered magnet magnetic property of different grain size hydrogenation dysprosium and density contrast
? Remanent magnetism (kGs) Coercive force (kOe) Magnetic energy product (MGOe) Density (g/cm 3)
Original magnet 1 13.8 16.8 45.1 7.52
Embodiment 1 13.6 20.0 44.8 7.53
Comparative example 1-1 13.0 17.8 40.2 7.49
Comparative example 1-2 12.6 17.2 38.4 7.46
Comparative example 1-3 12.4 13.2 37.2 7.35
Embodiment 2
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 500 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 4% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1050 DEG C of sintering 5 hours, then carry out secondary heat treatment: wherein 800 DEG C of first order heat treatment temperatures, are incubated 4 hours; 500 DEG C of second level heat treatment temperatures, are incubated 5 hours; The final sintered magnet that obtains.
Comparative example 2-1
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 50 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 4% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1050 DEG C of sintering 5 hours, then carry out secondary heat treatment: wherein 800 DEG C of first order heat treatment temperatures, are incubated 4 hours; 500 DEG C of second level heat treatment temperatures, are incubated 5 hours; The final sintered magnet that obtains.
Comparative example 2-2
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopting the quick-fried and ball-milling technology of hydrogen to prepare average grain diameter is the hydrogenation dysprosium powder of 4 microns.
(4) the hydrogenation dysprosium metal micron powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 6% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Comparative example 2-3
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) neodymium iron boron powder is orientated in 3T magnetic field and compressing;
(4) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Table 2. adopts the particle doped preparation regeneration sintered magnet magnetic property of different grain size hydrogenation dysprosium and density contrast
? Remanent magnetism (kGs) Coercive force (kOe) Magnetic energy product (MGOe) Density (g/cm 3)
Original magnet 2 13.0 20.8 40.8 7.55
Embodiment 2 12.7 29.2 39.6 7.54
Comparative example 2-1 11.9 22.5 35.8 7.47
Comparative example 2-2 11.5 22.2 33.7 7.41
Comparative example 2-3 11.4 15.6 32.6 7.36
Embodiment 3
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 300 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 3% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1030 DEG C of sintering 6 hours, then carry out secondary heat treatment: wherein 850 DEG C of first order heat treatment temperatures, are incubated 4.5 hours; 480 DEG C of second level heat treatment temperatures, are incubated 4.5 hours; The final sintered magnet that obtains.
Comparative example 3-1
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopt physical gas phase deposition technology to prepare the hydrogenation dysprosium nanometer powder that average grain diameter is 30 nanometers.
(4) the hydrogenation dysprosium nano metal powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 3% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1030 DEG C of sintering 6 hours, then carry out secondary heat treatment: wherein 850 DEG C of first order heat treatment temperatures, are incubated 4.5 hours; 480 DEG C of second level heat treatment temperatures, are incubated 4.5 hours; The final sintered magnet that obtains.
Comparative example 3-2
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) adopting the quick-fried and ball-milling technology of hydrogen to prepare average grain diameter is the hydrogenation dysprosium powder of 4 microns.
(4) the hydrogenation dysprosium metal micron powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is 6% of NdFeB material powder weight, and two kinds of powder are mixed;
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Comparative example 3-3
(1) waste and old rare-earth permanent-magnet electric machine magnet steel composition is Nd 25.4dy 5fe 67.2co 1.1cu 0.2al 0.1b 1.The waste and old magnet steel of neodymium iron boron of removing coating is placed in to 5% nitric acid alcohol and after 10 seconds, cleans at alcoholic solution, dry up.Useless magnet steel is placed in vacuum tube furnace, carries out 150 DEG C, 0.1MPa hydrogen pressure and inhale hydrogen 3 hours, 600 DEG C, 1 × 10 -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to 3 microns.
(3) neodymium iron boron powder is orientated in 3T magnetic field and compressing;
(4) pressed compact is inserted in vacuum sintering furnace, 1080 DEG C of sintering 7 hours, then carry out secondary heat treatment: wherein 920 DEG C of first order heat treatment temperatures, are incubated 5 hours; 550 DEG C of second level heat treatment temperatures, are incubated 4 hours; The final sintered magnet that obtains.
Table 3. adopts the particle doped preparation regeneration sintered magnet magnetic property of different grain size hydrogenation dysprosium and density contrast
? Remanent magnetism (kGs) Coercive force (kOe) Magnetic energy product (MGOe) Density (g/cm 3)
Original magnet 3 13.0 20.8 40.8 7.55
Embodiment 3 12.9 28.0 40.6 7.55
Comparative example 3-1 12.1 21.3 36.9 7.48
Comparative example 3-2 11.5 22.2 33.7 7.41
Comparative example 3-3 11.4 15.6 32.6 7.36
In sum, adopt every magnetic property index of regeneration magnet prepared by method of the present invention can be returned to original magnet level, wherein coercive force will be higher than original magnet level.Compared with granule hydrogenation dysprosium particle (being less than 100 nanometers) doping, there is higher remanent magnetism, coercive force and magnetic energy product; Compared with bulky grain hydrogenation dysprosium particle (being greater than 500 nanometers) doping, reaching on same coercitive basis, required hydrogenation dysprosium content is few, and therefore the remanent magnetism of magnet, magnetic energy product can well be replied simultaneously.Compared with conventional sintering technique, sintering temperature and the heat treatment temperature of regeneration sintered magnet are low, therefore can obtain higher coercive force.In addition, adopt the inventive method can make full use of existing equipment, technological process is short, and cost energy consumption is low, economizes on resources.

Claims (3)

1. utilize waste and old magnetic steel of magnetoelectric machine to prepare a method for high-coercive force regeneration Sintered NdFeB magnet, it is characterized in that, comprise the following steps:
(1) the waste and old rare-earth permanent-magnet electric machine magnet steel of removing coating is cleaned and is prepared into the quick-fried powder of neodymium iron boron hydrogen;
(2) adopt airflow milling technique that NdFeB magnetic powder is crushed to single crystal grain, obtain NdFeB material powder;
(3) adopt physical gas phase deposition technology to prepare hydrogenation dysprosium powder, its particle diameter is 100-500 nanometer;
(4) the hydrogenation dysprosium nanometer powder of step (3) gained is joined in the NdFeB material powder of step (2), the adding proportion of hydrogenation dysprosium nanometer powder is the 2-4% of NdFeB material powder weight, and two kinds of powder are mixed.
(5) will in 3T magnetic field, be orientated through even mixed powder and compressing;
(6) pressed compact is inserted in vacuum sintering furnace, at 1000-1050 DEG C of sintering 5-7 hour, then carry out secondary heat treatment: wherein first order heat treatment temperature 800-900 DEG C, insulation 4-5 hour; Second level heat treatment temperature 450-500 DEG C, insulation 4-5 hour; The final sintered magnet that obtains.
2. according to the method for claim 1, it is characterized in that, step (1) is placed in 5% nitric acid alcohol by the waste and old rare-earth permanent-magnet electric machine magnet steel of removing coating and cleans at alcoholic solution after 10 seconds, dries up; Be placed at and in vacuum tube furnace, carry out inhaling hydrogen 3 hours, 600 DEG C, 1 × 10 under 150 DEG C, 0.1MPa hydrogen pressure -3pa dehydrogenation 10 hours, obtains the quick-fried powder of neodymium iron boron hydrogen.
3. the regeneration Sintered NdFeB magnet preparing according to the method for claim 1 or 2.
CN201410258657.8A 2014-06-11 2014-06-11 Method for manufacturing high-coercivity regenerated sintered neodymium-iron-boron magnet by waste permanent-magnet motor magnet steel Pending CN104036947A (en)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104439232A (en) * 2014-12-04 2015-03-25 浙江大学 Method for improving coercive force of sintered NdFeB magnet by adding dysprosium hydrogen compound and product
CN105215350A (en) * 2015-11-12 2016-01-06 苏州萨伯工业设计有限公司 The method of Nano metal powder preparation containing gadolinium rare earth permanent-magnetic material is added in steel refuse by magnetic
CN105234399A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing nano composite permanent magnetic material by adding gallium in waste magnetic steel
CN105234398A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing holmium-containing rare earth permanent magnetic material by adding nano metal powder in waste magnetic steel
CN105234394A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing rare earth permanent magnetic material by adding liquid-phase nano gadolinium in waste magnetic steel
CN105234397A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing rare earth permanent magnetic material by adding liquid-phase dysprosium in waste magnetic steel
EP3090821A4 (en) * 2015-03-08 2017-03-22 Beijing University Of Technology Method for preparing neodymium-iron-boron magnet by utilizing waste material and neodymium-iron-boron magnet
CN114864268A (en) * 2022-06-07 2022-08-05 安徽吉华新材料有限公司 Preparation method of high-coercivity regenerative magnet
CN117153514A (en) * 2023-10-18 2023-12-01 宁波合力磁材技术有限公司 Remanufactured magnet utilizing waste neodymium-iron-boron magnet and preparation process thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1345073A (en) * 2000-09-20 2002-04-17 爱知制钢株式会社 Manufacture and raw material powder of anisotropic magnetic powder and plastics magnet
CN101521069A (en) * 2008-11-28 2009-09-02 北京工业大学 Method for preparing heavy rare earth hydride nano-particle doped sintered NdFeB permanent magnet
CN102723166A (en) * 2012-06-29 2012-10-10 温州市南磁科技有限公司 NdFeB permanent magnet and processing process thereof
JP2014017480A (en) * 2012-06-15 2014-01-30 Nissan Motor Co Ltd GRAIN BOUNDARY MODIFICATION METHOD OF Nd-Fe-B-BASED MAGNET

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1345073A (en) * 2000-09-20 2002-04-17 爱知制钢株式会社 Manufacture and raw material powder of anisotropic magnetic powder and plastics magnet
CN101521069A (en) * 2008-11-28 2009-09-02 北京工业大学 Method for preparing heavy rare earth hydride nano-particle doped sintered NdFeB permanent magnet
JP2014017480A (en) * 2012-06-15 2014-01-30 Nissan Motor Co Ltd GRAIN BOUNDARY MODIFICATION METHOD OF Nd-Fe-B-BASED MAGNET
CN102723166A (en) * 2012-06-29 2012-10-10 温州市南磁科技有限公司 NdFeB permanent magnet and processing process thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104439232A (en) * 2014-12-04 2015-03-25 浙江大学 Method for improving coercive force of sintered NdFeB magnet by adding dysprosium hydrogen compound and product
EP3090821A4 (en) * 2015-03-08 2017-03-22 Beijing University Of Technology Method for preparing neodymium-iron-boron magnet by utilizing waste material and neodymium-iron-boron magnet
CN105215350A (en) * 2015-11-12 2016-01-06 苏州萨伯工业设计有限公司 The method of Nano metal powder preparation containing gadolinium rare earth permanent-magnetic material is added in steel refuse by magnetic
CN105234399A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing nano composite permanent magnetic material by adding gallium in waste magnetic steel
CN105234398A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing holmium-containing rare earth permanent magnetic material by adding nano metal powder in waste magnetic steel
CN105234394A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing rare earth permanent magnetic material by adding liquid-phase nano gadolinium in waste magnetic steel
CN105234397A (en) * 2015-11-12 2016-01-13 苏州萨伯工业设计有限公司 Method for preparing rare earth permanent magnetic material by adding liquid-phase dysprosium in waste magnetic steel
CN114864268A (en) * 2022-06-07 2022-08-05 安徽吉华新材料有限公司 Preparation method of high-coercivity regenerative magnet
CN117153514A (en) * 2023-10-18 2023-12-01 宁波合力磁材技术有限公司 Remanufactured magnet utilizing waste neodymium-iron-boron magnet and preparation process thereof

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