WO2019223431A1 - 一种低成本扩散源合金和晶界扩散磁体及其制备方法 - Google Patents

一种低成本扩散源合金和晶界扩散磁体及其制备方法 Download PDF

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WO2019223431A1
WO2019223431A1 PCT/CN2019/081438 CN2019081438W WO2019223431A1 WO 2019223431 A1 WO2019223431 A1 WO 2019223431A1 CN 2019081438 W CN2019081438 W CN 2019081438W WO 2019223431 A1 WO2019223431 A1 WO 2019223431A1
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diffusion
magnet
alloy
grain boundary
diffusion source
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PCT/CN2019/081438
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French (fr)
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冯海波
谭敏
李安华
陈鑫烁
陈红升
李卫
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钢铁研究总院
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
    • H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
    • H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
    • H01F41/0293—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets diffusion of rare earth elements, e.g. Tb, Dy or Ho, into permanent magnets
    • 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

Definitions

  • the invention relates to the field of rare earth permanent magnet materials, and relates to a low-cost diffusion source alloy for magnet grain boundary diffusion, a grain boundary diffusion magnet, and a preparation method thereof.
  • NdFeB permanent magnet materials are widely used in the fields of electromechanical, information, robotics and intelligent manufacturing due to their excellent comprehensive magnetic properties.
  • ordinary heavy-weight rare earth sintered neodymium-iron-boron magnets have a lower Curie temperature and poor high-temperature magnetic properties, which cannot meet the requirements for (hybrid) electric vehicle traction motors, wind energy generators and other high temperature conditions, limiting the application of magnets range.
  • the traditional method to solve this problem is to add a heavy rare earth element Dy, Tb to the mother alloy smelting, or add a fluoride, hydride or low melting point alloy of the heavy rare earth element Dy, Tb at the grain boundary.
  • This method can effectively improve the high temperature stability of the magnet, but it will consume a lot of heavy rare earth resources and increase the cost of raw materials.
  • the magnetic coupling of heavy rare earth atoms and iron atoms is antiferromagnetic coupling, the large amount of heavy rare earth elements will greatly reduce the residual magnetism and magnetic energy product of the magnet.
  • grain boundary diffusion technology In order to save resources and reduce costs, while avoiding a significant decrease in residual magnetism and magnetic energy product, grain boundary diffusion technology can be used.
  • the technology has simple process, low cost, small amount of heavy rare earth, large increase in coercive force of magnet, small decrease in remanence and magnetic energy product, and has a cost advantage when manufacturing small size high coercivity magnets.
  • the diffusion sources used for grain boundary diffusion are mainly heavy rare earth metals, oxides, fluorides, hydrides and low melting point alloys.
  • the low-melting alloy has a large cost advantage, and the coercive force of the magnet is significantly improved after the grain boundary diffusion, which has a high cost performance.
  • the content of heavy rare earth elements is relatively high, and the cost of the diffusion source alloy can be further reduced.
  • Chinese invention patent application No. 201710130288.8 discloses 'a method for preparing high coercivity NdFeB magnets by grain boundary diffusion', which uses a hot dip plating method to coat the surface of NdFeB magnets with Thin layer low melting point metal or low melting point alloy, the composition of the low melting point alloy is RM, R is one or more of La, Ce, Pr, Nd, Gd, Tb, Dy, Ho and Y, M is Cu, Al Or more of Ga, Zn, Sn, and Ag.
  • the inexpensive rare earth element Ce is only a selective element in the low melting point alloy, and is not an essential element.
  • an object of the present invention is to provide a low-cost diffusion source alloy for magnet grain boundary diffusion, a grain boundary diffusion magnet to which the low-cost diffusion source alloy is attached, and a method for preparing the same.
  • the present invention provides the following technical solutions:
  • a low-cost diffusion source alloy The chemical composition of the diffusion source alloy includes the element Ce, light rare earth element LRE, heavy rare earth element HRE, and metal element M.
  • the atomic percentage is expressed as Ce x (LRE a HRE 1-a ) y M 100-xy ; where 0 ⁇ x ⁇ 20, 15 ⁇ y ⁇ 99.9 and 15 ⁇ x + y ⁇ 99.9, 0 ⁇ a ⁇ 1.0;
  • LRE is one or more of La, Pr, Nd, and Y
  • HRE is one or more of Tb, Dy, and Ho
  • M is one of Al, Cu, Zn, Ga, Ag, Pb, Bi, and Sn Or more.
  • the state of the diffusion source alloy during use is: molten alloy liquid of the diffusion source alloy, rapid quenched strip of the diffusion source alloy, quick-setting sheet of the diffusion source alloy, flakes of the diffusion source alloy, or diffusion source alloy Powder, or a diffusion source alloy slurry obtained by mixing an alloy powder of a diffusion source alloy with a solvent.
  • the diffusion source alloy is prepared by a method including, but not limited to:
  • a quick-setting sheet is prepared through a rapid-setting process, and then hydrogen-crushed and / or mechanically broken into alloy powder for grain boundary diffusion, or the quick-setting sheet is directly used for grain-boundary diffusion.
  • the alloying elements are heated to a molten state, cast into an ingot, and then prepared by one of the following methods:
  • the ingot is made into a diffusion source alloy powder through hydrogen crushing and / or mechanical crushing;
  • the ingot is heated to a molten state for grain boundary diffusion.
  • a grain boundary diffusion magnet with a low-cost diffusion source alloy attached to its surface is prepared by diffusion treatment and tempering treatment after the diffusion source alloy is attached to the surface of the original magnet, or only by diffusion treatment.
  • the original magnet is a sintered or tempered NdFeB magnet or cerium magnet.
  • a method for preparing a grain boundary diffusion magnet includes the following steps:
  • a diffusion source alloy is attached to the surface of the original magnet
  • Diffusion source alloy-attached magnets are subjected to diffusion treatment at 750 ° C to 1000 ° C for 0.5-24h to prepare grain boundary diffusion magnets, or after diffusion treatment at 750 ° C to 1000 ° C for 0.5 to 24h, they are then returned to 400 ° C to 700 ° C. Fire treatment was performed for 0.5-8 hours to prepare a grain boundary diffusion magnet.
  • step (4) the magnet with the diffusion source alloy is subjected to diffusion treatment at 850 ° C to 980 ° C for 4h to 24h, and then tempered at 430 ° C to 640 ° C for 2h to 6h to prepare a grain boundary diffusion magnet.
  • the content of heavy rare earth in the diffusion source is high, causing a lot of waste of rare earth elements.
  • the invention optimizes the alloy composition of the composition of the diffusion source alloy, and uses light rare earth elements, especially the inexpensive rare earth element cerium as an essential component, partially replaces the heavy rare earth elements, reduces the content of the heavy rare earth elements in the diffusion source, and makes the diffusion source alloy The cost of raw materials is reduced, and the cost-effectiveness of the grain boundary diffusion magnet is improved.
  • the melting point of the diffusion source alloy is adjusted, and the temperature coefficient of coercivity of the grain boundary diffusion magnet is improved by increasing the diffusion efficiency of the heavy rare earth element, and the grain boundary is improved. High temperature stability of diffusion magnets.
  • the present invention is different from the prior art Chinese invention patent application No. 201710130288.8 in that the prior art does not explain the role played by Ce in the grain boundary diffusion process, nor does it explain the diffusion of Ce-containing diffusion source alloys. , Brings other beneficial effects in addition to the increase of the coercive force of the magnet.
  • the present invention uses light rare-earth element, especially cheap rare-earth element Ce as an essential component, partially replaces heavy rare-earth element, reduces the content of heavy rare-earth element in the diffusion source, reduces the raw material cost of the diffusion source alloy, and improves the grain boundary diffusion magnet. Value for money.
  • Ce's role is to reduce and adjust the melting point of the alloy, increase the thickness and continuity of the grain boundary phase of the grain boundary diffusion magnet, and weaken the exchange coupling effect between the grains. The most important thing is that it can improve the coercivity temperature coefficient of the grain boundary diffusion magnet and increase the high temperature stability of the grain boundary diffusion magnet by improving the diffusion efficiency of heavy rare earth elements.
  • a low-cost diffusion source alloy for magnet grain boundary diffusion includes the elements Ce, light rare earth element LRE, heavy rare earth element HRE, and metal element M, which are expressed as Ce x (LRE a HRE in atomic percentage).
  • Ce x LRE a HRE in atomic percentage
  • 1-a ) y M 100-xy where 0 ⁇ x ⁇ 20, 15 ⁇ y ⁇ 99.9 and 15 ⁇ x + y ⁇ 99.9, 0 ⁇ a ⁇ 1.0; the LRE is in La, Pr, Nd, and Y HRE is one or more of Tb, Dy, and Ho; M is one or more of Al, Cu, Zn, Ga, Ag, Pb, Bi, and Sn.
  • the role of HRE is to increase the anisotropic field of the grains of the magnet
  • the role of Ce, LRE, and M is to adjust the melting point of the diffusion source alloy
  • Ce, LRE, and HRE can also increase the grain boundary diffusion magnet.
  • the thickness and continuity of the grain boundary phase weaken the exchange coupling effect between the grains.
  • the characteristic of this diffusion source alloy is that the diffusion source alloy must contain Ce. Its main function is to reduce and adjust the melting point of the alloy.
  • the grain boundary diffusion magnet is attached with a diffusion source
  • the alloy neodymium iron boron magnet or cerium magnet is prepared by diffusion treatment and tempering treatment.
  • the diffusion source alloy is prepared by a method including, but not limited to:
  • a quick-setting sheet is prepared through a rapid-setting process, and then hydrogen-crushed and / or mechanically broken into alloy powder for grain boundary diffusion, or the quick-setting sheet is directly used for grain-boundary diffusion.
  • the ingot is made into a diffusion source alloy powder through hydrogen crushing and / or mechanical crushing;
  • the ingot is heated to a molten state for grain boundary diffusion.
  • a grain boundary diffusion magnet The magnet is prepared by diffusion treatment and tempering treatment after the diffusion source alloy is attached to the surface of the original magnet, or is prepared by only diffusion treatment.
  • the original magnet is sintered or tempered. NdFeB magnet or cerium magnet.
  • the composition of the diffusion source alloy can be selected according to the content of Ce and heavy rare earths Dy and Tb in the original magnet and the performance of the original magnet.
  • the content of Ce in the original magnet when the content of Ce in the original magnet is relatively large, the content of Dy and Tb is relatively small, and the coercive force is relatively low, the content of Ce, LRE, and M in the diffusion source alloy may be appropriately increased, and the RHE content may be appropriately decreased; in the original magnet, the Ce content When the content of Dy and Tb is relatively small and the coercivity is high, the content of Ce, LRE, and M in the diffusion source alloy can be appropriately reduced, and the content of RHE can be appropriately increased.
  • the preparation process of the grain boundary diffusion magnet is as follows:
  • a magnet with a diffusion source alloy is subjected to diffusion treatment at 750 ° C to 1000 ° C for 0.5 to 24 hours to prepare a grain boundary diffusion magnet, or after diffusion treatment at 750 ° C to 1000 ° C for 0.5 to 24 hours, it is returned at 400 ° C to 700 ° C. Fire treatment was performed for 0.5-8 hours to prepare a grain boundary diffusion magnet.
  • the present invention is characterized by adding light rare earth elements to the diffusion source alloy, on the one hand, reducing the cost of raw materials, on the other hand, reducing the melting point of the diffusion source alloy, which is conducive to the diffusion of heavy rare earth elements, thereby improving the grain boundary diffusion magnet.
  • Coercivity temperature coefficient improves the high temperature stability of grain boundary diffusion magnets.
  • the mass ratio of ethanol to alloy is 1: 1.
  • the neodymium iron boron magnet (original magnet) is cut into a cylinder of ⁇ 10mm * 5mm.
  • the cylindrical magnet is immersed in the diffusion source alloy slurry, taken out and blow-dried in a glove box to obtain an adhered diffusion source alloy powder magnet.
  • the diffusion source alloy powder magnet is subjected to diffusion treatment at 850 ° C for 24 hours; and then tempered at 500 ° C for 2 hours to obtain a grain boundary diffusion magnet.
  • Comparative Example 1 The manufacturing process of Comparative Example 1 is the same as that of the grain boundary diffusion magnet of Example 1 except that the composition of the diffusion source alloy is Pr 7 Nd 28 Tb 35 Cu 20 Al 10 (atomic percentage).
  • the mass ratio of ethanol to alloy is 1: 1.
  • the adhered alloy powder magnet is subjected to diffusion treatment at 980 ° C for 10 hours and then tempered at 500 ° C for 2 hours to obtain a grain boundary diffusion magnet.
  • the magnets of Comparative Example 2 were the same as those of Example 2 except that the composition of the diffusion source alloy was Pr 80 Tb 10 Dy 5 Cu 2.5 Al 2.5 (atomic percentage).
  • the room temperature magnetic properties and the coercive force temperature coefficient (23-120 ° C) of the original magnet of Example 2, the magnet of Comparative Example 2 and the grain boundary diffusion magnet of Example 2 are shown in Table 2.
  • the mass ratio of ethanol to alloy is 1: 1.
  • the diffusion-treated magnet was tempered at 640 ° C for 2h to obtain a grain boundary diffusion magnet.
  • Comparative Example 3 is the same as that of the grain boundary diffusion magnet of Example 3, except that the composition of the diffusion source alloy is Dy 76 Cu 12 Al 12 (atomic percentage).
  • An arc furnace was used to melt the diffusion source alloy Ce 10 Pr 14 Nd 56 Dy 2 Al 18 (atomic percentage) to prepare an alloy ingot.
  • the alloy ingot was coarsely crushed, and then hydrogen cracked under a hydrogen pressure of 0.4 MPa. Ball milling was performed for 24 h under the protection of ethanol to obtain a diffusion source alloy slurry.
  • the mass ratio of ethanol to alloy is 1: 1.
  • the adhered alloy powder magnet is diffused at 940 ° C for 10 hours, and then tempered at 430 ° C for 6 hours to obtain a grain boundary diffusion magnet.
  • Comparative Example 4 is the same as that of Example 4 except that the composition of the diffusion source alloy is Pr 14 Nd 56 Dy 12 Al 18 (atomic percentage).
  • An arc furnace was used to melt the diffusion source alloy Ce 2 Nd 14 Dy 1 Cu 83 (atomic percentage) to prepare an alloy ingot.
  • the alloy ingot was coarsely crushed, and then hydrogen cracked under a hydrogen pressure of 0.4 MPa. Under the protection of ball milling for 24 hours, a diffusion source alloy slurry was obtained.
  • the mass ratio of ethanol to alloy is 1: 1.
  • the magnetite of Comparative Example 5 is the same as that of the grain boundary diffusion magnet of Example 5 except that the composition of the diffusion source alloy is Nd 14 Dy 3 Cu 83 (atomic percentage).
  • Table 5 shows the room temperature magnetic properties of the original magnet of Example 5, the magnet of Comparative Example 5, and the grain boundary diffusion magnet of Example 5.

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Abstract

本发明涉及一种用于磁体晶界扩散的低成本扩散源合金和一种晶界扩散磁体及其制备方法。扩散源合金的化学成分包括元素Ce、轻稀土元素LRE、重稀土元素HRE和金属元素M，按原子百分数表示为表示为Ce x(LRE aHRE 1-a) yM 100-x-y；其中，0＜x≤20，15≤y≤99.9且15＜x+y≤99.9，0≤a≤1.0；LRE为La、Pr、Nd和Y中一种或多种；HRE为Tb、Dy和Ho中一种或多种；M为Al、Cu、Zn、Ga、Ag、Pb、Bi和Sn中的一种或多种。本发明采用轻稀土元素特别是铈部分取代重稀土元素，降低了扩散源合金的原料成本，调节了扩散源合金的熔点，通过提高重稀土元素扩散效率，改善了晶界扩散磁体的矫顽力温度系数，提高了晶界扩散磁体的高温稳定性。

Description

一种低成本扩散源合金和晶界扩散磁体及其制备方法 技术领域
本发明涉及稀土永磁材料领域，涉及一种用于磁体晶界扩散的低成本扩散源合金和一种晶界扩散磁体及其制备方法。
背景技术
钕铁硼永磁材料因其优异的综合磁性能而广泛应用于机电、信息、机器人和智能制造等领域。然而，普通无重稀土烧结钕铁硼磁体的居里温度较低，高温磁性能差，不能满足(混合)电动汽车牵引电机、风能发电机等在高温条件下的使用要求，限制了磁体的应用范围。
传统解决此问题的方法为母合金熔炼添加重稀土元素Dy、Tb或者晶界添加重稀土元素Dy、Tb的氟化物、氢化物或低熔点合金。此方法能有效提高磁体的高温稳定性，但会大量消耗重稀土资源，增加原材料成本。同时，由于重稀土原子和铁原子的磁性耦合方式为反铁磁耦合，重稀土元素的大量加入将会使磁体的剩磁和磁能积大幅下降。
为了节约资源，降低成本，同时避免剩磁和磁能积大幅下降，可以采用晶界扩散技术。该技术工艺简单、成本低廉、重稀土使用量少、磁体矫顽力提升幅度大、剩磁和磁能积下降幅度小，在制造小尺寸高矫顽力磁体时具有成本优势。
目前，用于晶界扩散的扩散源主要有重稀土金属、氧化物、氟化物、氢化物和低熔点合金。在这些扩散源中，低熔点合金的成本优势较大，且晶界扩散后磁体矫顽力提高明显，具有较高的性价比。但在 目前的扩散源合金中，重稀土元素的含量较高，扩散源合金的成本还能进一步降低。
现有技术中，中国发明专利申请号No.201710130288.8公开了‘一种晶界扩散制备高矫顽力钕铁硼磁体的方法’，其利用热浸镀方法在钕铁硼磁体的表面包覆一薄层低熔点金属或低熔点合金，其中低熔点合金成分组成为R-M，R为La、Ce、Pr、Nd、Gd、Tb、Dy、Ho和Y中的一种及以上，M为Cu、Al、Ga、Zn、Sn、Ag中的一种及以上。但是该申请文件中，廉价的稀土元素Ce仅为该低熔点合金中的选择性元素，而不是必要元素。
发明内容
针对上述技术问题，本发明的目的是提供一种用于磁体晶界扩散的低成本扩散源合金、附着该低成本扩散源合金的晶界扩散磁体及它们的制备方法。
为了实现上述目的，本发明提供了如下技术方案：
一种低成本扩散源合金，该扩散源合金的化学成分包括元素Ce、轻稀土元素LRE、重稀土元素HRE和金属元素M，按原子百分数表示为Ce x(LRE aHRE 1-a) yM 100-x-y；其中，0＜x≤20，15≤y≤99.9且15＜x+y≤99.9，0≤a≤1.0；
LRE为La、Pr、Nd和Y中一种或多种；HRE为Tb、Dy和Ho中一种或多种；M为Al、Cu、Zn、Ga、Ag、Pb、Bi和Sn中的一种或多种。
优选地，0.1≤x≤20，15≤y≤94.9且17≤x+y≤95，0≤a≤0.97。
所述扩散源合金在使用时的状态为：扩散源合金的熔融合金液、或扩散源合金的快淬薄带、或扩散源合金的速凝片、或扩散源合金的薄片、或扩散源合金的粉末、或扩散源合金的合金粉末与溶剂混合得 到的扩散源合金浆液。
所述扩散源合金由包括但不限于下述方法制备得到：
(1)由合金元素熔炼为熔融合金液用于晶界扩散；
(2)合金元素熔炼为熔融合金液后，通过快淬方法制备为薄带用于晶界扩散；
(3)合金元素熔炼为熔融合金液后，通过速凝工艺制备成速凝片，然后氢破碎和/或机械破碎为合金粉用于晶界扩散，或直接将速凝片用于晶界扩散；
(4)将合金元素加热到熔融状态，浇铸为铸锭，然后通过下述方式之一制备得到：
①铸锭经过氢破碎和/或机械破碎制成扩散源合金粉末；
②将铸锭感应熔化，通过快淬工艺制备成薄带用于晶界扩散；
③将铸锭切成薄片用于晶界扩散；
④将铸锭加热为熔融状态用于晶界扩散。
一种表面附着低成本扩散源合金的晶界扩散磁体，该晶界扩散磁体为在原始磁体表面附着扩散源合金后，经扩散处理和回火处理制备获得，或仅由扩散处理制备获得，所述原始磁体为烧结态或回火态的钕铁硼磁体或铈磁体。
一种晶界扩散磁体的制备方法，该方法包括如下步骤：
(1)将原始磁体加工成所需尺寸；
(2)清洗掉原始磁体表面的油污，并打磨掉原始磁体表层氧化物；
(3)在原始磁体表面附着扩散源合金；
(4)附着扩散源合金的磁体在750℃～1000℃扩散处理0.5-24h，制备得到晶界扩散磁体，或者在750℃～1000℃扩散处理0.5～24h后，再在400℃～700℃回火处理0.5～8h，制备得到晶界扩散磁体。
在步骤(4)中，附着扩散源合金的磁体在850℃～980℃扩散处理4h～24h后，再在430℃～640℃回火处理2h～6h，制备得到晶界扩散磁体。
与现有技术相比，本发明的有益效果在于：
(1)在传统扩散源中，不管是采用氢化物、氟化物、氧化物、稀土金属，还是低熔点合金作扩散源，扩散源中重稀土含量高，造成稀土元素的大量浪费。本发明对扩散源合金的成分进行合金成分优化，采用轻稀土元素，特别是廉价的稀土元素铈为必要成分，部分取代重稀土元素，降低扩散源中重稀土元素的含量，使扩散源合金的原料成本降低，提高晶界扩散磁体的性价比。
(2)通过采用轻稀土元素特别是Ce部分取代重稀土元素，调节扩散源合金的熔点，通过提高重稀土元素扩散效率，使晶界扩散磁体的矫顽力温度系数得到改善，提高了晶界扩散磁体的高温稳定性。
进一步，本发明与现有技术中国发明专利申请号No.201710130288.8的区别在于，该现有技术并未说明Ce在晶界扩散过程中所起到的作用，也未说明扩散含Ce扩散源合金后，带来除磁体矫顽力增加外的其他的有益效果。
但是本发明采用轻稀土元素，特别是廉价的稀土元素Ce为必要成分，部分取代重稀土元素，降低扩散源中重稀土元素的含量，使扩散源合金的原料成本降低，提高了晶界扩散磁体的性价比。其中，Ce的作用为降低和调整合金熔点，增加晶界扩散磁体晶界相的厚度和连续性，减弱晶粒间的交换耦合作用。最重要的是，它能够通过提高重稀土元素扩散效率，改善晶界扩散磁体的矫顽力温度系数，提高晶界扩散磁体的高温稳定性。
具体实施方式
下面结合实施例对本发明进行进一步说明。
一种用于磁体晶界扩散的低成本扩散源合金，扩散源合金的化学成分包括元素Ce、轻稀土元素LRE、重稀土元素HRE和金属元素M，按原子百分数表示为Ce x(LRE aHRE 1-a) yM 100-x-y，其中，0＜x≤20，15≤y≤99.9且15＜x+y≤99.9，0≤a≤1.0；所述LRE为La、Pr、Nd和Y中的一种或多种；HRE为Tb、Dy和Ho中的一种或多种；M为Al、Cu、Zn、Ga、Ag、Pb、Bi和Sn中的一种或多种。
在该扩散源合金中，HRE的作用为提高磁体晶粒的各向异性场，Ce、LRE和M的作用为调整扩散源合金的熔点，此外，Ce、LRE和HRE还能增加晶界扩散磁体晶界相的厚度和连续性，减弱晶粒间的交换耦合作用；本扩散源合金的特色之处在于该扩散源合金中必须含有Ce，其主要作用为降低和调整合金熔点，可以根据扩散工艺需要获得最佳的合金熔点和扩散温度，显著提高重稀土元素扩散效率，改善晶界扩散磁体的矫顽力温度系数，提高晶界扩散磁体的高温稳定性；晶界扩散磁体为附着了扩散源合金的钕铁硼磁体或铈磁体，经扩散处理和回火处理制备得到。
所述扩散源合金由包括但不限于下述方法制备：
(1)由合金元素熔炼为熔融合金液用于晶界扩散；
(2)合金元素熔炼为熔融合金液后，通过快淬工艺制备成薄带用于晶界扩散；
(3)合金元素熔炼为熔融合金液后，通过速凝工艺制备成速凝片，然后氢破碎和/或机械破碎为合金粉用于晶界扩散，或直接将速凝片用于晶界扩散；
(4)由合金元素加热到熔融状态，浇铸为铸锭，然后通过下述方式之一制备；
①铸锭经过氢破碎和/或机械破碎制成扩散源合金粉末；
②将铸锭感应熔化，通过快淬工艺制备成快淬带用于晶界扩散；
③将铸锭切成薄片用于晶界扩散；
④将铸锭加热为熔融状态用于晶界扩散。
一种晶界扩散磁体，该磁体为在原始磁体表面附着扩散源合金后，经扩散处理和回火处理制备获得，或仅经过扩散处理制备获得，所述原始磁体为烧结态或回火态的钕铁硼磁体或铈磁体。
所述的扩散源合金成分可以根据原始磁体中Ce和重稀土Dy、Tb的含量以及原始磁体的性能进行选择。
如在原始磁体中Ce含量比较多、Dy和Tb含量比较少、矫顽力比较低时，扩散源合金中Ce、LRE和M含量可以适当增加、RHE含量可以适当减少；在原始磁体中Ce含量比较少、Dy和Tb含量比较多、矫顽力比较高时，扩散源合金中Ce、LRE和M含量可以适当减少、RHE含量可以适当增多。
所述晶界扩散磁体制备过程如下：
(1)将烧结态或回火态的钕铁硼磁体或铈磁体(原始磁体)加工成所需尺寸；
(2)清洗掉原始磁体表面的油污，并打磨掉原始磁体表层氧化物；
(3)在打磨掉表层氧化物的原始磁体表面附着扩散源合金；
(4)附着扩散源合金的磁体在750℃～1000℃扩散处理0.5～24h，制备得到晶界扩散磁体，或者在750℃～1000℃扩散处理0.5～24h后，再在400℃～700℃回火处理0.5～8h，制备得到晶界扩散磁体。
本发明的特点是将轻稀土元素加入到扩散源合金中，一方面降低了原材料成本，另一方面使扩散源合金的熔点降低，有利于重稀土元素的扩散，从而改善了晶界扩散磁体的矫顽力温度系数，提高晶界扩散 磁体的高温稳定性。
实施例1
制备扩散源合金：
采用电弧炉熔炼扩散源合金Ce 5Pr 7Nd 28Tb 30Cu 20Al 10(原子百分数)，制备得到合金铸锭，将合金铸锭进行粗破碎，然后在0.4MPa的氢压下进行氢破，最后在乙醇的保护下球磨24h，获得扩散源合金浆液。
其中，乙醇与合金的质量比为1:1。
制备晶界扩散磁体：
(1)将钕铁硼磁体(原始磁体)切成Φ10mm*5mm的圆柱。
(2)清洗掉钕铁硼磁体表面的油污，并用砂纸打磨掉钕铁硼磁体表面的氧化层。
(3)将圆柱形磁体浸入扩散源合金浆液中，捞出并在手套箱中吹干，得到附着扩散源合金粉末磁体。
(4)附着扩散源合金粉末磁体在850℃扩散处理24h；然后在500℃回火处理2h，得到晶界扩散磁体。
制备比较例1磁体：
比较例1磁体除扩散源合金成分为Pr 7Nd 28Tb 35Cu 20Al 10(原子百分数)外，其他制备步骤与实施例1晶界扩散磁体的制备步骤相同。
实施例1原始磁体、比较例1磁体和实施例1晶界扩散磁体室温磁性能和矫顽力温度系数(23～140℃)如表1所示。
表1
  Br(kGs) (BH)max(MGOe) Hcj(kOe) β(％/℃)
实施例1原始磁体 14.20 49.98 12.15 -0.588
比较例1磁体 13.84 47.34 20.32 -0.547
实施例1晶界扩散磁体 13.95 48.23 21.27 -0.544
实施例2
制备扩散源合金：
采用电弧炉熔炼扩散源合金Ce 0.1Pr 80Tb 10Dy 4.9Cu 2.5Al 2.5(原子百分数)，制备得到合金铸锭，将合金铸锭进行粗破碎，然后在0.4MPa的氢压下进行氢破，最后在乙醇的保护下球磨24h，获得扩散源合金浆液。
其中，乙醇与合金的质量比为1:1。
制备晶界扩散磁体：
(1)将铈磁体(原始磁体)切成Φ10mm*5mm的圆柱。
(2)清洗掉表面的油污，并用砂纸打磨掉表面的氧化层。
(3)将圆柱形磁体浸入合金浆液中，捞出并在手套箱中吹干，得到附着合金粉末磁体。
(4)附着合金粉末磁体在980℃扩散处理10h，然后在500℃回火处理2h，得到晶界扩散磁体。
制备比较例2磁体：
比较例2磁体除扩散源合金成分为Pr 80Tb 10Dy 5Cu 2.5Al 2.5(原子百分数)外，其他实验步骤与实施例2晶界扩散磁体的制备步骤相同。
实施例2原始磁体、比较例2磁体和实施例2晶界扩散磁体室温磁性能性能和矫顽力温度系数(23～120℃)如表2所示。
表2
  Br(kGs) (BH)max(MGOe) Hcj(kOe)  (％/℃)
实施例2原始磁体 12.57 37.84 14.37 -0.633
比较例2磁体 12.39 36.57 18.41 -0.591
实施例2晶界扩散磁体 12.44 37.02 19.26 -0.588
实施例3
制备扩散源合金：
采用电弧炉熔炼扩散源合金Ce 20Dy 56Cu 12Al 12(原子百分数)，制备得到合金铸锭，将合金铸锭进行粗破碎，然后在0.4MPa的氢压下进行氢破，最后在乙醇的保护下球磨24h，获得扩散源合金浆液。
其中，乙醇与合金的质量比为1:1。
制备晶界扩散磁体：
(1)将铈磁体(原始磁体)切成Φ10mm*5mm的圆柱。
(2)清洗掉表面的油污，并用砂纸打磨掉表面的氧化层。
(3)将圆柱形磁体浸入合金浆液中，捞出并在手套箱中吹干，得到附着合金粉末磁体。
(4)附着合金粉末磁体在940℃扩散处理4h。
(5)扩散处理磁体在640℃回火处理2h，得到晶界扩散磁体。
制备比较例3磁体：
比较例3磁体除扩散源合金成分为Dy 76Cu 12Al 12(原子百分数)外，其他实验步骤与实施例3晶界扩散磁体的制备步骤相同。
实施例3原始磁体、比较例3磁体和实施例3晶界扩散磁体室温磁性能性能如表3所示。
表3
  Br(kGs) (BH)max(MGOe) Hcj(kOe)
实施例3原始磁体 12.01 34.43 12.23
比较例3磁体 11.89 33.97 15.07
实施例3晶界扩散磁体 11.80 33.56 15.65
实施例4
制备扩散源合金：
采用电弧炉熔炼扩散源合金Ce 10Pr 14Nd 56Dy 2Al 18(原子百分数)，制备得到合金铸锭，将合金铸锭进行粗破碎，然后在0.4MPa的氢压下进 行氢破，最后在乙醇的保护下球磨24h，获得扩散源合金浆液。
其中，乙醇与合金的质量比为1:1。
制备晶界扩散磁体：
(1)将铈磁体(原始磁体)切成Φ10mm*5mm的圆柱。
(2)清洗掉表面的油污，并用砂纸打磨掉表面的氧化层。
(3)将圆柱形磁体浸入合金浆液中，捞出并在手套箱中吹干，得到附着合金粉末磁体。
(4)附着合金粉末磁体在940℃扩散处理10h，然后在430℃回火处理6h，得到晶界扩散磁体。
制备比较例4磁体：
比较例4磁体除扩散源合金成分为Pr 14Nd 56Dy 12Al 18(原子百分数)外，其他实验步骤与实施例4晶界扩散磁体的制备步骤相同。
实施例4原始磁体、比较例4磁体和实施例4晶界扩散磁体室温磁性能性能如表4所示。
表4
  Br(kGs) (BH)max(MGOe) Hcj(kOe)
实施例4原始磁体 10.24 25.13 9.030
比较例4磁体 10.05 24.17 10.47
实施例4晶界扩散磁体 10.12 24.51 10.84
实施例5
制备扩散源合金：
采用电弧炉熔炼扩散源合金Ce 2Nd 14Dy 1Cu 83(原子百分数)，制备得到合金铸锭，将合金铸锭进行粗破碎，然后在0.4MPa的氢压下进行氢破，最后在乙醇的保护下球磨24h，获得扩散源合金浆液。
其中，乙醇与合金的质量比为1:1。
制备晶界扩散磁体：
(1)将铈磁体(原始磁体)切成Φ10mm*5mm的圆柱。
(2)清洗掉表面的油污，并用砂纸打磨掉表面的氧化层。
(3)将圆柱形磁体浸入合金浆液中，捞出并在手套箱中吹干，得到附着合金粉末磁体。
(4)附着合金粉末磁体在940℃扩散处理10h，得到晶界扩散磁体。
制备比较例5磁体：
比较例5磁体除扩散源合金成分为Nd 14Dy 3Cu 83(原子百分数)外，其他实验步骤与实施例5晶界扩散磁体的制备步骤相同。
实施例5原始磁体、比较例5磁体和实施例5晶界扩散磁体室温磁性能性能如表5所示。
表5
  Br(kGs) (BH)max(MGOe) Hcj(kOe)
实施例5原始磁体 9.180 12.6 2.376
比较例5磁体 9.106 18.88 3.509
实施例5晶界扩散磁体 9.134 19.39 3.875
上述的对实施例的描述是为便于该技术领域的普通技术人员能理解和使用发明。熟悉本技术领域的人员显然可以容易地对这些实施例作出各种修改，并把在此说明的一般原理应用到其他实施例中，而不必经过创造性的劳动。因此，本发明不限于上述实施例。本技术领域人员根据本发明的揭示，不脱离本发明范畴所做出的改进和修改都应该在本发明的保护范围之内。

Claims (7)

  1. 一种低成本扩散源合金，其特征在于：
    该扩散源合金的化学成分包括元素Ce、轻稀土元素LRE、重稀土元素HRE和金属元素M，按原子百分数表示为Ce x(LRE aHRE 1-a) yM 100-x-y；其中，0＜x≤20，15≤y≤99.9且15＜x+y≤99.9，0≤a≤1.0；
    LRE为La、Pr、Nd和Y中一种或多种；HRE为Tb、Dy和Ho中一种或多种；M为Al、Cu、Zn、Ga、Ag、Pb、Bi和Sn中的一种或多种。
  2. 根据权利要求1所述的低成本扩散源合金，其特征在于：0.1≤x≤20，15≤y≤94.9且17≤x+y≤95，0≤a≤0.97。
  3. 根据权利要求1所述的低成本扩散源合金，其特征在于：所述扩散源合金在使用时的状态为：扩散源合金的熔融合金液、或扩散源合金的快淬薄带、或扩散源合金的速凝片、或扩散源合金的薄片、或扩散源合金的粉末、或扩散源合金的合金粉末与溶剂混合得到的扩散源合金浆液。
  4. 根据权利要求1所述的低成本扩散源合金，其特征在于：所述扩散源合金由包括但不限于下述方法制备得到：
    (1)由合金元素熔炼为熔融合金液用于晶界扩散；
    (2)合金元素熔炼为熔融合金液后，通过快淬方法制备为薄带用于晶界扩散；
    (3)合金元素熔炼为熔融合金液后，通过速凝工艺制备成速凝片，然后氢破碎和/或机械破碎为合金粉用于晶界扩散，或直接将速凝片用 于晶界扩散；
    (4)将合金元素加热到熔融状态，浇铸为铸锭，然后通过下述方式之一制备得到：
    ①铸锭经过氢破碎和/或机械破碎制成扩散源合金粉末；
    ②将铸锭感应熔化，通过快淬工艺制备成薄带用于晶界扩散；
    ③将铸锭切成薄片用于晶界扩散；
    ④将铸锭加热为熔融状态用于晶界扩散。
  5. 一种表面附着权利要求1所述的低成本扩散源合金的晶界扩散磁体，其特征在于：
    该晶界扩散磁体为在原始磁体表面附着扩散源合金后，经扩散处理和回火处理制备获得，或仅由扩散处理制备获得，所述原始磁体为烧结态或回火态的钕铁硼磁体或铈磁体。
  6. 一种权利要求5所述的晶界扩散磁体的制备方法，其特征在于：该方法包括如下步骤：
    (1)将原始磁体加工成所需尺寸；
    (2)清洗掉原始磁体表面的油污，并打磨掉原始磁体表层氧化物；
    (3)在原始磁体表面附着扩散源合金；
    (4)附着扩散源合金的磁体在750℃～1000℃扩散处理0.5-24h，制备得到晶界扩散磁体，或者在750℃～1000℃扩散处理0.5～24h后，再在400℃～700℃回火处理0.5～8h，制备得到晶界扩散磁体。
  7. 根据权利要求6所述的晶界扩散磁体的制备方法，其特征在于：在步骤(4)中，附着扩散源合金的磁体在850℃～980℃扩散处理4h～24h后，再在430℃～640℃回火处理2h～6h，制备得到晶界扩散磁体。
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CN109360703B (zh) * 2018-11-29 2020-10-16 钢铁研究总院 一种热压低温扩散热变形纳米晶磁体及其制备方法
WO2020155113A1 (zh) * 2019-02-01 2020-08-06 天津三环乐喜新材料有限公司 稀土扩散磁体的制备方法及稀土扩散磁体
CN112530689A (zh) * 2020-11-27 2021-03-19 中钢天源股份有限公司 一种提高高丰度铈磁体晶界扩散效果的方法
CN112941457B (zh) * 2021-01-21 2022-09-20 华南理工大学 一种钕铁硼磁体用合金复合晶界扩散剂及其制备方法与应用
CN113871123A (zh) 2021-09-24 2021-12-31 烟台东星磁性材料股份有限公司 低成本稀土磁体及制造方法
CN116403792A (zh) * 2021-12-28 2023-07-07 福建省长汀金龙稀土有限公司 一种晶界扩散材料、r-t-b磁体及其制备方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104882266A (zh) * 2015-06-16 2015-09-02 北京科技大学 晶界扩渗轻稀土-铜合金制备高矫顽力钕铁硼磁体的方法
CN107256795A (zh) * 2017-06-27 2017-10-17 北京科技大学 利用两步晶界扩散工艺制备高性能烧结钕铁硼磁体的方法
CN108417380A (zh) * 2018-05-21 2018-08-17 钢铁研究总院 一种低成本扩散源合金和晶界扩散磁体及其制备方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109300640B (zh) * 2013-06-05 2021-03-09 丰田自动车株式会社 稀土磁体及其制造方法
CN105170976A (zh) * 2015-10-23 2015-12-23 北京科技大学 一种压坯扩渗后低温烧结制备高矫顽力钕铁硼的方法
CN105321702B (zh) * 2015-11-19 2017-10-20 北京科技大学 一种提高烧结NdFeB磁体矫顽力的方法
CN105895358A (zh) * 2016-06-15 2016-08-24 北京科技大学 一种钕铁硼磁体晶界扩渗的制备方法
CN106887323A (zh) * 2017-03-07 2017-06-23 北京科技大学 一种晶界扩散制备高矫顽力钕铁硼磁体的方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104882266A (zh) * 2015-06-16 2015-09-02 北京科技大学 晶界扩渗轻稀土-铜合金制备高矫顽力钕铁硼磁体的方法
CN107256795A (zh) * 2017-06-27 2017-10-17 北京科技大学 利用两步晶界扩散工艺制备高性能烧结钕铁硼磁体的方法
CN108417380A (zh) * 2018-05-21 2018-08-17 钢铁研究总院 一种低成本扩散源合金和晶界扩散磁体及其制备方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112857932A (zh) * 2021-01-12 2021-05-28 昆明理工大学 一种银镓扩散合金的金相样品制备方法
EP4060691A1 (en) * 2021-03-16 2022-09-21 Toyota Jidosha Kabushiki Kaisha Rare earth magnet and producing method thereof
US11869690B2 (en) 2021-03-16 2024-01-09 Toyota Jidosha Kabushiki Kaisha Rare earth magnet and producing method thereof

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