JP2006303436A - Rare earth permanent magnet - Google Patents

Rare earth permanent magnet Download PDF

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JP2006303436A
JP2006303436A JP2006008140A JP2006008140A JP2006303436A JP 2006303436 A JP2006303436 A JP 2006303436A JP 2006008140 A JP2006008140 A JP 2006008140A JP 2006008140 A JP2006008140 A JP 2006008140A JP 2006303436 A JP2006303436 A JP 2006303436A
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magnet
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rare earth
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grain boundary
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JP4702549B2 (en
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Hajime Nakamura
中村  元
Koichi Hirota
晃一 廣田
Masanobu Shimao
正信 島尾
Takehisa Minowa
武久 美濃輪
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Shin Etsu Chemical Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a high performance R-Fe-B based permanent magnet imparting high coercive force (R is two kinds or more selected from rare earth elements including Sc and Y). <P>SOLUTION: In a sintered magnet body having R<SP>1</SP><SB>a</SB>R<SP>2</SP><SB>b</SB>T<SB>c</SB>A<SB>d</SB>F<SB>e</SB>O<SB>f</SB>M<SB>g</SB>composition, constitutional elements of F and R<SP>2</SP>are distributed such that the concentration of component increases in average from the center toward the surface of the magnet body, and a grain boundary where the concentration of R<SP>2</SP>/(R<SP>1</SP>+R<SP>2</SP>) is higher in average than that in a main phase crystal grains consisting of tetragonal (R<SP>1</SP>, R<SP>2</SP>)<SB>2</SB>T<SB>14</SB>A continues down to a depth of at least 10 μm from the surface of the magnet in three-dimensional mesh shape. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

本発明は、高保磁力を与える高性能希土類永久磁石に関する。   The present invention relates to a high performance rare earth permanent magnet that provides a high coercive force.

Nd−Fe−B系永久磁石は、その優れた磁気特性のために、ますます用途が広がってきている。近年、環境問題への対応から家電をはじめ、産業機器、電気自動車、風力発電へ磁石の応用の幅が広がったことに伴い、Nd−Fe−B系磁石の高保磁力化が要求されている。   Nd-Fe-B permanent magnets are increasingly used because of their excellent magnetic properties. In recent years, Nd—Fe—B magnets have been required to have a higher coercive force as the range of application of magnets has expanded to address home appliances, industrial equipment, electric vehicles, and wind power generation in response to environmental problems.

本系磁石の保磁力の増大に関しては、結晶粒の微細化を図る、Nd量を増やした組成合金を用いる、あるいは効果のある元素を添加する等、様々なアプロ−チがある中で、現在最も一般的な手法はDyやTbでNdの一部を置換した組成合金を用いることである。Nd2Fe14B化合物のNdをこれらの元素で置換することで、化合物の異方性磁界が増大し、保磁力も増大する。一方で、DyやTbによる置換は化合物の飽和磁気分極を減少させる。従って、上記手法で保磁力の増大を図る限りでは残留磁束密度の低下は避けられない。 Regarding the increase in coercive force of this magnet, there are various approaches such as refinement of crystal grains, use of a composition alloy with increased Nd content, or addition of an effective element. The most common method is to use a composition alloy in which a part of Nd is substituted with Dy or Tb. By substituting Nd of the Nd 2 Fe 14 B compound with these elements, the anisotropic magnetic field of the compound increases and the coercive force also increases. On the other hand, substitution with Dy or Tb reduces the saturation magnetic polarization of the compound. Therefore, as long as the coercive force is increased by the above method, a decrease in residual magnetic flux density is inevitable.

Nd−Fe−B磁石は結晶粒界面で逆磁区の核が生成する外部磁界の大きさが保磁力となる。逆磁区の核生成には結晶粒界面の構造が強く影響しており、界面近傍における結晶構造の乱れが磁気的な構造の乱れを招き、逆磁区の生成を助長する。本系磁石の保磁力の理論的な最大値はTbやDyを含まない組成において6MA/mにも及ぶのに対し、実際に逆磁区が生成する磁界、即ち保磁力は、たかだか1MA/m程度である。従って、界面近傍の磁気構造を改善するだけで、飛躍的な保磁力の増大が期待できるにもかかわらず、保磁力増大のための有効な組織形態を実際に得ることは困難であった。   In the Nd—Fe—B magnet, the coercive force is the magnitude of the external magnetic field generated by the nucleus of the reverse magnetic domain at the crystal grain interface. The structure of the crystal grain interface strongly influences the nucleation of the reverse magnetic domain, and the disorder of the crystal structure in the vicinity of the interface causes the disorder of the magnetic structure and promotes the generation of the reverse magnetic domain. The theoretical maximum value of the coercive force of this magnet reaches 6 MA / m in the composition not containing Tb or Dy, whereas the magnetic field actually generated by the reverse magnetic domain, that is, the coercive force is about 1 MA / m. It is. Therefore, it is difficult to actually obtain an effective structure for increasing the coercive force, although a dramatic increase in coercive force can be expected by simply improving the magnetic structure near the interface.

このような状況の中で、磁石体表面にDy金属をスパッタして熱処理を施すことで、高い残留磁束密度を維持しながら高い保磁力が得られることが報告された(非特許文献1)。この手法と同一な原理ではあるが、3次元的にスパッタできるよう装置に改良を加えて工程簡略化を試みた例も報告されている(特開2004−304038号公報:特許文献1)。更に、希土類金属の供給法としてスパッタリング以外にも蒸着、イオンプレーティング、レーザーデポジション、CVD、MO−CVD、メッキ等が提案されている(特開2005−11973号公報:特許文献2)。しかし、メッキ法を除いて何れの手法も効率的な手法とは言えず、更に、特許文献2においても指摘されているとおり、上記手法を用いた場合には成膜、及びその後の加熱処理終了までの一連の工程において、希土類金属の酸化や不純物の混入防止のために酸素や水蒸気が数十ppm以下の清浄雰囲気下であることが必須であり、磁石材料の製造工程としては生産性が極端に低いという問題があった。   In such a situation, it has been reported that a high coercive force can be obtained while maintaining a high residual magnetic flux density by performing heat treatment by sputtering Dy metal on the surface of the magnet body (Non-patent Document 1). Although it is based on the same principle as this method, there has been reported an example in which the process is simplified by improving the apparatus so that sputtering can be performed three-dimensionally (Japanese Patent Laid-Open No. 2004-304038: Patent Document 1). In addition to sputtering, vapor deposition, ion plating, laser deposition, CVD, MO-CVD, plating, and the like have been proposed as a rare earth metal supply method (Japanese Patent Laid-Open No. 2005-11973: Patent Document 2). However, none of the methods except the plating method can be said to be an efficient method. Further, as pointed out in Patent Document 2, when the above method is used, the film formation and the subsequent heat treatment are completed. In the series of processes up to this point, it is essential that oxygen and water vapor be in a clean atmosphere with several tens of ppm or less in order to prevent oxidation of rare earth metals and contamination of impurities, and productivity is extremely high as a magnet material manufacturing process. There was a problem of being low.

なお従来、特許第3471876号公報(特許文献3)には、希土類磁石(希土類元素Rのうち少なくとも1種以上含有)をフッ素系ガス雰囲気中又はフッ素系ガスを含有する雰囲気中でフッ素化処理して、該磁石の表層部にその構成相中のRとのRF3化合物又はROXY化合物(X,Yの各々の値が0<X<1.5でかつ2X+Y=3を満足する)あるいはその両化合物の混合物を形成させ、更には200〜1,200℃の温度で熱処理を施すことからなる耐食性の優れた希土類磁石が開示されている。 Conventionally, in Japanese Patent No. 3447176 (Patent Document 3), a rare earth magnet (containing at least one rare earth element R) is fluorinated in a fluorine-based gas atmosphere or a fluorine-containing gas atmosphere. In the surface layer of the magnet, an RF 3 compound or RO X F Y compound with R in the constituent phase (each value of X and Y satisfies 0 <X <1.5 and 2X + Y = 3) Alternatively, a rare earth magnet having excellent corrosion resistance is disclosed, which is formed by forming a mixture of both compounds and further performing heat treatment at a temperature of 200 to 1,200 ° C.

特開2003−282312号公報(特許文献4)には、少なくとも、R−Fe−(B,C)系焼結磁石用合金粉末と、希土類元素のフッ素化合物粉末とを混合し、この混合粉末を磁場配向、圧粉成形して焼結すること、この場合、前記混合粉末の中に3〜20重量%の希土類元素(好ましくはDy及び/又はTb)のフッ素化合物を含ませることにより、R−Fe−(B,C)系焼結磁石(但し、Rは希土類元素であり、Rの50%以上はNd及び/又はPrとする)であって、Nd2Fe14B型結晶から主として構成される主相の結晶粒界又は粒界三重点に粒状の粒界相が形成され、前記粒界相が希土類元素のフッ素化合物を含み、前記希土類元素のフッ素化合物の焼結磁石全体に対する含有量が3〜20重量%の範囲にある着磁性が改善されたR−Fe−(B,C)系焼結磁石、特にR−Fe−(B,C)系焼結磁石(但し、Rは希土類元素であり、Rの50%以上はNd及び/又はPrとする)であって、Nd2Fe14B型結晶から主として構成される主相と、希土類元素のフッ素化合物を含む粒界相とを含んで構成され、前記主相中にDy及び/又はTbが含まれ、該主相中に、Dy及び/又はTbの濃度が、該主相全体におけるDy及び/又はTbの濃度の平均値より低い領域が、形成されているR−Fe−(B,C)系焼結磁石が開示されている。 In JP-A-2003-28212 (Patent Document 4), at least an R—Fe— (B, C) -based sintered magnet alloy powder and a rare earth element fluorine compound powder are mixed, and this mixed powder is used. Magnetic field orientation, compacting and sintering, in which case the mixed powder contains a fluorine compound of 3 to 20% by weight of a rare earth element (preferably Dy and / or Tb) Fe- (B, C) based sintered magnet (where R is a rare earth element and 50% or more of R is Nd and / or Pr), and is mainly composed of Nd 2 Fe 14 B type crystals. A grain boundary phase is formed at a crystal grain boundary or grain boundary triple point of the main phase, the grain boundary phase contains a rare earth element fluorine compound, and the content of the rare earth element fluorine compound in the entire sintered magnet is Magnetization in the range of 3-20% by weight is improved Improved R—Fe— (B, C) based sintered magnet, particularly R—Fe— (B, C) based sintered magnet (where R is a rare earth element, 50% or more of R is Nd and / or Or Pr), which is configured to include a main phase mainly composed of Nd 2 Fe 14 B-type crystals and a grain boundary phase including a fluorine compound of a rare earth element, and Dy and / or In the main phase, a region where the concentration of Dy and / or Tb is lower than the average value of the concentration of Dy and / or Tb in the entire main phase is formed in R-Fe- ( B, C) based sintered magnets are disclosed.

しかし、これらの提案においても、保磁力を増大させる点でなお十分ではない。   However, these proposals are still not sufficient in terms of increasing the coercive force.

K. T. Park, K. Hiraga and M. Sagawa, “Effect of Metal−Coating and Consecutive Heat Treatment on Coercivity of Thin Nd−Fe−B Sintered Magnets”, Proceedings of the Sixteen International Workshop on Rare−Earth Magnets and Their Applications, Sendai, p.257 (2000)K. T.A. Park, K.M. Hiraga and M.M. Sagawa, "Effect of Metal-Coating and Consecutive Heat Treatment on Coercivity of Thin Nd-Fe-B Sintered Magnets", Proceedings of the Sixteen International Workshop on Rare-Earth Magnets and Their Applications, Sendai, p. 257 (2000) 特開2004−304038号公報JP 2004-304038 A 特開2005−11973号公報Japanese Patent Laid-Open No. 2005-11973 特許第3471876号公報Japanese Patent No. 3447176 特開2003−282312号公報JP 2003-28212 A

本発明は、上述した従来の問題点に鑑みなされたもので、高保磁力を与える高性能R−Fe−B系永久磁石(RはSc及びYを含む希土類元素から選ばれる2種以上)を提供することを目的とするものである。   The present invention has been made in view of the above-described conventional problems, and provides a high-performance R—Fe—B permanent magnet (R is selected from two or more selected from rare earth elements including Sc and Y) that provides a high coercive force. It is intended to do.

本発明者らは、Nd−Fe−B系焼結磁石に代表されるR−Fe−B系焼結磁石(RはSc及びYを含む希土類元素から選ばれる1種又は2種以上)に対し、化学的に安定で取扱いの容易なRのフッ化物を磁石体表面から供給できる状態で焼結温度よりも低い温度で加熱することでRとFが共に磁石体に高効率に粒界部に沿うように吸収され、結晶粒の界面近傍にのみDyやTb及びFを濃化させ、DyやTbが濃化した粒界相を磁石表面から連続的に網目状の形態とし、DyやTb及びFが磁石体中心より磁石体表面に向かって平均的に見ると含有濃度が濃くなるように分布させることで、保磁力を増大できることを見出し、この発明を完成したものである。   For the R-Fe-B sintered magnet represented by the Nd-Fe-B sintered magnet (R is one or more selected from rare earth elements including Sc and Y). By heating at a temperature lower than the sintering temperature in a state where a chemically stable and easy-to-handle R fluoride can be supplied from the surface of the magnet body, both R and F are efficiently applied to the grain boundary part. And the Dy, Tb, and F are concentrated only in the vicinity of the interface of the crystal grains, and the grain boundary phase in which the Dy and Tb are concentrated is continuously formed in a network form from the magnet surface. The present invention has been completed by finding that the coercive force can be increased by distributing F so that the content concentration increases as viewed from the center of the magnet body toward the surface of the magnet body on average.

即ち、本発明は、下記の希土類永久磁石を提供する。
(1)R1 a2 bcdefg組成(R1はSc及びYを含み、Tb及びDyを除く希土類元素から選ばれる1種又は2種以上、R2はTb及びDyから選ばれる1種又は2種、TはFe及びCoから選ばれる1種又は2種、AはB及びCから選ばれる1種又は2種、MはAl、Cu、Zn、In、Si、P、S、Ti、V、Cr、Mn、Ni、Ga、Ge、Zr、Nb、Mo、Pd、Ag、Cd、Sn、Sb、Hf、Ta、Wの中から選ばれる1種又は2種以上、a〜gは合金の原子%で、10≦a+b≦15、3≦d≦15、0.01≦e≦4、0.04≦f≦4、0.01≦g≦11、残部がc)を有する焼結磁石体であって、その構成元素であるF及びR2が磁石体中心より磁石体表面に向かって平均的に含有濃度が濃くなるように分布し、かつ、R2/(R1+R2)の濃度が(R1,R2214A正方晶からなる主相結晶粒中のR2/(R1+R2)濃度より平均的に濃い結晶粒界が磁石表面から少なくとも10μmの深さまで連続した三次元網目状の形態をなしていることを特徴とする希土類永久磁石。
(2)結晶粒界部の磁石体表面より少なくとも20μmの深さ領域にまで、結晶粒界部に(R1,R2)の酸フッ化物が存在し、該領域において円相当径が1μm以上の該酸フッ化物粒子が1平方ミリメ−トル当たり2,000個以上の割合で分散し、かつ当該酸フッ化物が面積分率で1%以上を占めていることを特徴とする(1)記載の希土類永久磁石。
(3)結晶粒界部に存在する酸フッ化物に含まれるNd及び/又はPrのR1+R2に対する原子分率が、該酸フッ化物及びR3の酸化物(R3はSc及びYを含む希土類元素から選ばれる1種あるいは2種以上)を除いた結晶粒界部におけるNd及び/又はPrのR1+R2に対する原子分率よりも高いことを特徴とする(1)又は(2)記載の希土類永久磁石。
(4)R1がNd及び/又はPrを10原子%以上含有することを特徴とする(1)乃至(3)のいずれかに記載の希土類永久磁石。
(5)TがFeを60原子%以上含有することを特徴とする(1)乃至(4)のいずれかに記載の希土類永久磁石。
(6)AがBを80原子%以上含有することを特徴とする(1)乃至(5)のいずれかに記載の希土類永久磁石。
That is, the present invention provides the following rare earth permanent magnets.
(1) R 1 a R 2 b T c A d F e O f M g composition (R 1 includes Sc and Y, 1 or 2 or more selected from rare earth elements excluding Tb and Dy, R 2 is One or two selected from Tb and Dy, T is one or two selected from Fe and Co, A is one or two selected from B and C, M is Al, Cu, Zn, In, One or two selected from Si, P, S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, W Seeds or more, a to g are atomic% of the alloy, 10 ≦ a + b ≦ 15, 3 ≦ d ≦ 15, 0.01 ≦ e ≦ 4, 0.04 ≦ f ≦ 4, 0.01 ≦ g ≦ 11, balance there a sintered magnet body having a c), F and R 2 is the constituent element becomes darker on average contain a concentration towards the magnet body surface than the magnet body center Uni distributed, and, R 2 / (R 1 + R 2) Concentration of (R 1, R 2) 2 T 14 R 2 / of the main phase crystal grains in which A consists of tetragonal (R 1 + R 2) than the concentration A rare earth permanent magnet having a three-dimensional network shape in which an average dark grain boundary is continuous from a magnet surface to a depth of at least 10 μm.
(2) (R 1 , R 2 ) oxyfluoride is present in the crystal grain boundary part to a depth region of at least 20 μm from the surface of the magnet body in the crystal grain boundary part, and the equivalent circle diameter in the region is 1 μm or more. The oxyfluoride particles are dispersed at a rate of 2,000 or more per square millimeter, and the oxyfluoride occupies 1% or more in area fraction (1) Rare earth permanent magnet.
(3) Nd contained in the oxyfluoride is present in the crystal grain boundaries and / or Pr atom fraction for R 1 + R 2 of an oxide of the acid fluoride and R 3 a (R 3 are Sc and Y (1) or (2) characterized by being higher than the atomic fraction of Nd and / or Pr with respect to R 1 + R 2 at the grain boundary excluding one or more selected from rare earth elements contained The rare earth permanent magnet described.
(4) The rare earth permanent magnet according to any one of (1) to (3), wherein R 1 contains 10 atomic% or more of Nd and / or Pr.
(5) The rare earth permanent magnet according to any one of (1) to (4), wherein T contains 60 atomic% or more of Fe.
(6) The rare earth permanent magnet according to any one of (1) to (5), wherein A contains 80 atomic% or more of B.

本発明によれば、高保磁力を与えるR−Fe−B系焼結磁石を提供することができる。   ADVANTAGE OF THE INVENTION According to this invention, the R-Fe-B type sintered magnet which gives a high coercive force can be provided.

本発明の希土類永久磁石は、下記式(1)で示される組成を有しているものである。
1 a2 bcdefg (1)
ここで、R1はSc及びYを含み、Tb及びDyを除く希土類元素から選ばれる1種又は2種以上、R2はTb及びDyから選ばれる1種又は2種、TはFe及びCoから選ばれる1種又は2種、AはB(ホウ素)及びC(炭素)から選ばれる1種又は2種、MはAl、Cu、Zn、In、Si、P、S、Ti、V、Cr、Mn、Ni、Ga、Ge、Zr、Nb、Mo、Pd、Ag、Cd、Sn、Sb、Hf、Ta、Wの中から選ばれる1種又は2種以上である。
a〜gは合金の原子%で、10≦a+b≦15、3≦d≦15、0.01≦e≦4、0.04≦f≦4、0.01≦g≦11で、残部はcである。
The rare earth permanent magnet of the present invention has a composition represented by the following formula (1).
R 1 a R 2 b T c A d F e O f M g (1)
Here, R 1 contains Sc and Y, and is one or more selected from rare earth elements excluding Tb and Dy, R 2 is one or two selected from Tb and Dy, and T is Fe and Co. One or two selected, A is one or two selected from B (boron) and C (carbon), M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, One or more selected from Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, and W.
a to g are atomic% of the alloy, 10 ≦ a + b ≦ 15, 3 ≦ d ≦ 15, 0.01 ≦ e ≦ 4, 0.04 ≦ f ≦ 4, 0.01 ≦ g ≦ 11, and the balance is c It is.

この場合、R1としては、Sc、Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Ho、Er、Yb及びLuが挙げられ、好ましくはNd及びPrを主体とし、R1中Nd及び/又はPrが10原子%以上、より好ましくは50原子%以上含有することが好ましい。 In this case, examples of R 1 include Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Ho, Er, Yb, and Lu, preferably Nd and Pr are mainly used, and Nd in R 1 And / or Pr is preferably contained in an amount of 10 atomic% or more, more preferably 50 atomic% or more.

また、R1とR2(Tb及び/又はDy)の合計量a+bは、上記の通り10〜15原子%であるが、より好ましくは12〜15原子%である。この場合、R2の量bは0.01〜8原子%、より好ましくは0.05〜6原子%、更に好ましくは0.1〜5原子%であることが好ましい。 The total amount a + b of R 1 and R 2 (Tb and / or Dy) is 10 to 15 atomic% as described above, and more preferably 12 to 15 atomic%. In this case, the amount b of R 2 is preferably 0.01 to 8 atomic%, more preferably 0.05 to 6 atomic%, and still more preferably 0.1 to 5 atomic%.

更に、TはFe及び/又はCoであるが、好ましくは60原子%以上、特に70原子%以上であり、この場合、Coは0原子%であってもよいが、残留磁束密度の温度安定性を向上させるなどの点で1原子%以上、より好ましくは3原子%以上、特に5原子%以上含有してもよい。   Further, T is Fe and / or Co, preferably 60 atomic% or more, particularly 70 atomic% or more, and in this case, Co may be 0 atomic%, but the temperature stability of the residual magnetic flux density. 1 atom% or more, more preferably 3 atom% or more, and particularly 5 atom% or more may be contained.

Aは、上述した通り、B及び/又はCであるが、AはBを80原子%以上、特に85原子%以上含有していることが好ましい。Aの量dは3〜15原子%であるが、好ましくは4〜12原子%、より好ましくは5〜8原子%である。   As described above, A is B and / or C, but it is preferable that A contains B at 80 atomic% or more, particularly 85 atomic% or more. The amount d of A is 3 to 15 atomic%, preferably 4 to 12 atomic%, more preferably 5 to 8 atomic%.

F(フッ素)の含有量eは、0.01〜4原子%であるが、好ましくは0.02〜3.5原子%、特に0.05〜3.5原子%であり、フッ素含有量が少なすぎると、保磁力増大の効果が認められなくなり、多すぎると、粒界相が変質し、保磁力が減少する。   The content e of F (fluorine) is 0.01 to 4 atomic%, preferably 0.02 to 3.5 atomic%, particularly 0.05 to 3.5 atomic%, and the fluorine content is If the amount is too small, the effect of increasing the coercive force is not recognized. If the amount is too large, the grain boundary phase is altered and the coercive force is decreased.

O(酸素)の含有量fは0.04〜4原子%であるが、好ましくは0.04〜3.5原子%、特に0.04〜3原子%である。   The content f of O (oxygen) is 0.04 to 4 atomic%, preferably 0.04 to 3.5 atomic%, particularly 0.04 to 3 atomic%.

更に、他金属元素Mの含有量gは、上述した通り0.01〜11原子%であるが、好ましくは0.01〜8原子%、特に0.02〜5原子%であり、0.05原子%以上、特に0.1原子%以上含まれていてもよい。   Further, the content g of the other metal element M is 0.01 to 11 atomic% as described above, preferably 0.01 to 8 atomic%, particularly 0.02 to 5 atomic%, 0.05 It may be contained in atomic percent or more, particularly 0.1 atomic percent or more.

この場合、本発明の希土類永久磁石は、その焼結磁石体のF及びR2が、当該磁石体の中心より磁石体表面に向かって平均的にF及びR2の含有濃度が濃くなるように分布している。つまり、磁石体の表面部においてF及びR2の濃度が最も高く、中心に向かってその濃度が漸次低下していくものである。なお、該磁石体の中心部において、Fは存在しなくてもよいが、結晶粒界部の磁石体表面から少なくとも20μmの深さまでの領域において、その結晶粒界部にR1及びR2の酸フッ化物、典型的には(R1 1-x2 x)OF[xは0〜1の数]が存在していることが好ましい。また、本発明において、該焼結磁石中のいわゆる(R1,R2214A正方晶からなる主相結晶粒の周りを取り囲む結晶粒界部において、結晶粒界に含まれるR2/(R1+R2)の濃度が主相結晶粒中のR2/(R1+R2)濃度より平均的に濃くなっているものであるが、この場合、10μmの深さ、より好ましくは13μmの深さ、更に好ましくは16μmの深さまで、上記R2/(R1+R2)の濃度が(R1,R2214A正方晶からなる主相結晶粒中のR2/(R1+R2)濃度より、平均的に濃い結晶粒界が磁石表面から連続した三次元網目状をなしていることが必要である。結晶粒界がこのようなR2高濃度の連続三次元網目状を有することにより、高保磁力を有するものである。 In this case, the rare earth permanent magnet of the present invention, as its F and R 2 of the sintered magnet body, on average concentration of the F and R 2 towards the magnet body surface from the center of the magnet body becomes darker Distributed. That is, the concentration of F and R 2 is highest at the surface portion of the magnet body, and the concentration gradually decreases toward the center. In the central part of the magnet body, F may not be present, but in a region from the surface of the magnetic body of the crystal grain boundary part to a depth of at least 20 μm, R 1 and R 2 are present in the crystal grain boundary part. It is preferred that an acid fluoride, typically (R 1 1−x R 2 x ) OF [x is a number from 0 to 1], is present. Further, in the present invention, R 2 in the so-called (R 1, R 2) 2 T 14 A grain boundary part surrounding the periphery of the main phase crystal grains consisting of tetragonal in the sintered magnet, which includes the grain boundaries / (R 1 + R 2) but the concentration of those which is average darker than R 2 / (R 1 + R 2) concentration in the main phase crystal grains, in this case, 10 [mu] m depth, and more preferably depth of 13 .mu.m, to more preferably the depth of 16 [mu] m, the R 2 / concentration of (R 1 + R 2) is (R 1, R 2) 2 T 14 a R of the main phase crystal grains in consisting of tetragonal 2 / From the (R 1 + R 2 ) concentration, it is necessary that the crystal grain boundaries that are denser on average have a three-dimensional network shape continuous from the magnet surface. The crystal grain boundary has such a continuous three-dimensional network having a high R 2 concentration, thereby having a high coercive force.

また、本発明の永久磁石においては、上述したように、結晶粒界部の磁石体表面より少なくとも20μmの深さ領域にまで、結晶粒界部にR2の酸フッ化物が存在しているものであるが、この場合該領域において円相当径が1μm以上の該酸フッ化物粒子が1平方ミリメートル当たり2,000個以上、好ましくは3,000個以上、更に好ましくは4,000〜20,000個の割合で分散し、かつ当該酸フッ化物が面積分率で1%以上、好ましくは2%以上、更に好ましくは2.5〜10%を占めるものである。なお、粒子の個数及び面積分率の測定は、EPMAの組成像を画像処理することで円相当径が1μm以上の酸フッ化物を検出し、測定した。 In the permanent magnet of the present invention, as described above, the R 2 oxyfluoride is present in the crystal grain boundary part to a depth region of at least 20 μm from the surface of the magnet body in the crystal grain boundary part. However, in this case, 2,000 or more, preferably 3,000 or more, more preferably 4,000 to 20,000 oxyfluoride particles having a circle equivalent diameter of 1 μm or more per square millimeter in the region are used. And the oxyfluoride occupies 1% or more, preferably 2% or more, and more preferably 2.5 to 10% in terms of area fraction. The number of particles and the area fraction were measured by detecting an oxyfluoride having an equivalent circle diameter of 1 μm or more by subjecting an EPMA composition image to image processing.

更に、結晶粒界部に存在する酸フッ化物に含まれるNd及び/又はPrのR1+R2に対する原子分率が、該酸フッ化物及びR3の酸化物(R3はSc及びYを含む希土類元素から選ばれる1種あるいは2種以上)を除いた結晶粒界部におけるNd及び/又はPrのR1+R2に対する原子分率よりも高いことが好ましい。 Furthermore, Nd contained in the oxyfluoride is present in the crystal grain boundaries and / or Pr R 1 + R 2 against atomic fraction of oxide of the acid fluoride and R 3 (R 3 is inclusive of Sc and Y It is preferably higher than the atomic fraction of Nd and / or Pr with respect to R 1 + R 2 at the grain boundary excluding one or more selected from rare earth elements.

本発明の希土類永久磁石は、R−Fe−B系焼結磁石体に、その表面からR2成分及びフッ素原子を含有する粉末を供給し、吸収させることによって得ることができる。 The rare earth permanent magnet of the present invention can be obtained by supplying an R—Fe—B based sintered magnet body with a powder containing an R 2 component and a fluorine atom from the surface thereof and absorbing it.

ここで、上記R−Fe−B系焼結磁石体は、常法に従い、母合金を粗粉砕、微粉砕、成形、焼結させることにより得ることができる。   Here, the R—Fe—B based sintered magnet body can be obtained by roughly pulverizing, finely pulverizing, forming and sintering the mother alloy according to a conventional method.

この場合、母合金は、R、T、A、Mを含有する。RはSc及びYを含む希土類元素から選ばれる1種又は2種以上で、具体的にはSc、Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Yb及びLuが挙げられ、好ましくはNd、Pr、Dyを主体とする。これらSc及びYを含む希土類元素は合金全体の10〜15原子%、特に12〜15原子%であることが好ましく、更に好ましくはR中にNdとPrあるいはそのいずれか1種を全Rに対して10原子%以上、特に50原子%以上含有することが好適である。TはFe及びCoから選ばれる1種又は2種で、Feは合金全体の50原子%以上、特に65原子%以上含有することが好ましい。AはB及びCから選ばれる1種又は2種で、Bは合金全体の2〜15原子%、特に3〜8原子%含有することが好ましい。MはAl、Cu、Zn、In、Si、P、S、Ti、V、Cr、Mn、Ni、Ga、Ge、Zr、Nb、Mo、Pd、Ag、Cd、Sn、Sb、Hf、Ta、Wの中から選ばれる1種又は2種以上を0.01〜11原子%、特に0.1〜5原子%含有してもよい。残部はN、O等の不可避的な不純物である。   In this case, the master alloy contains R, T, A, and M. R is one or more selected from rare earth elements including Sc and Y, specifically, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb and Lu are mentioned, preferably Nd, Pr and Dy. These rare earth elements including Sc and Y are preferably 10 to 15 atomic%, particularly 12 to 15 atomic% of the whole alloy, and more preferably Nd and Pr or any one of them in R is based on the total R. It is preferable to contain 10 atomic% or more, especially 50 atomic% or more. T is one or two selected from Fe and Co, and Fe is preferably contained in an amount of 50 atomic% or more, particularly 65 atomic% or more of the whole alloy. A is one or two selected from B and C, and B is preferably contained in an amount of 2 to 15 atomic%, particularly 3 to 8 atomic% of the whole alloy. M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, You may contain 0.01-11 atomic%, especially 0.1-5 atomic% of 1 type (s) or 2 or more types chosen from W. The balance is inevitable impurities such as N and O.

母合金は原料金属あるいは合金を真空あるいは不活性ガス、好ましくはAr雰囲気中で溶解したのち、平型やブックモ−ルドに鋳込む、あるいはストリップキャストにより鋳造することで得られる。また、本系合金の主相であるR2Fe14B化合物組成に近い合金と焼結温度で液相助剤となるRリッチな合金とを別々に作製し、粗粉砕後に秤量混合する、いわゆる2合金法も本発明には適用可能である。但し、主相組成に近い合金に対して、鋳造時の冷却速度や合金組成に依存してα−Feが残存しやすく、R2Fe14B化合物相の量を増やす目的で必要に応じて均質化処理を施す。その条件は真空あるいはAr雰囲気中にて700〜1,200℃で1時間以上熱処理する。液相助剤となるRリッチな合金については上記鋳造法のほかに、いわゆる液体急冷法やストリップキャスト法も適用できる。 The mother alloy can be obtained by melting a raw metal or alloy in a vacuum or an inert gas, preferably in an Ar atmosphere, and then casting it into a flat mold or a book mold, or casting it by strip casting. Also, an alloy close to the R 2 Fe 14 B compound composition that is the main phase of this alloy and an R-rich alloy that becomes a liquid phase aid at the sintering temperature are separately prepared, and are weighed and mixed after coarse pulverization. A two alloy method is also applicable to the present invention. However, for alloys close to the main phase composition, α-Fe is likely to remain depending on the cooling rate during casting and the alloy composition, and it is homogeneous as necessary for the purpose of increasing the amount of R 2 Fe 14 B compound phase. The process is applied. The conditions are heat treatment at 700 to 1,200 ° C. for 1 hour or more in vacuum or Ar atmosphere. In addition to the above casting method, a so-called liquid quenching method or strip casting method can be applied to the R-rich alloy serving as the liquid phase aid.

上記合金は、通常0.05〜3mm、特に0.05〜1.5mmに粗粉砕される。粗粉砕工程にはブラウンミルあるいは水素粉砕が用いられ、ストリップキャストにより作製された合金の場合は水素粉砕が好ましい。粗粉は、例えば高圧窒素を用いたジェットミルにより通常0.2〜30μm、特に0.5〜20μmに微粉砕される。この時、高圧窒素に微量の酸素を混合することで、焼結体の酸素量が制御される。インゴット作製時に混入する酸素と微粉から焼結体に到るまでに吸収した酸素とを合わせて、最終的な焼結体に含まれる酸素量は0.04〜4原子%、特に0.04〜3.5原子%であることが好ましい。   The alloy is generally coarsely pulverized to 0.05 to 3 mm, particularly 0.05 to 1.5 mm. Brown mill or hydrogen pulverization is used for the coarse pulverization process, and hydrogen pulverization is preferable in the case of an alloy produced by strip casting. The coarse powder is usually finely pulverized to 0.2 to 30 μm, particularly 0.5 to 20 μm, for example, by a jet mill using high-pressure nitrogen. At this time, the amount of oxygen in the sintered body is controlled by mixing a small amount of oxygen with high-pressure nitrogen. The oxygen amount contained in the final sintered body is 0.04 to 4 atomic%, particularly 0.04 to 4% by combining the oxygen mixed during the preparation of the ingot and the oxygen absorbed from the fine powder to the sintered body. It is preferably 3.5 atomic%.

微粉末は磁界中圧縮成形機で成形され、焼結炉に投入される。焼結は真空あるいは不活性ガス雰囲気中、通常900〜1,250℃、特に1,000〜1,100℃で行われる。得られた焼結磁石は、正方晶R2Fe14B化合物を主相として60〜99体積%、特に好ましくは80〜98体積%含有し、残部は0.5〜20体積%のRに富む相、0〜10体積%のBに富む相、0.1〜10体積%のRの酸化物及び不可避的不純物により生成した炭化物、窒化物、水酸化物のうち少なくとも1種あるいはこれらの混合物又は複合物からなる。 The fine powder is formed by a compression molding machine in a magnetic field and put into a sintering furnace. Sintering is usually performed at 900 to 1,250 ° C, particularly 1,000 to 1,100 ° C in a vacuum or an inert gas atmosphere. The obtained sintered magnet contains a tetragonal R 2 Fe 14 B compound as a main phase in an amount of 60 to 99% by volume, particularly preferably 80 to 98% by volume, and the remainder is rich in R of 0.5 to 20% by volume. At least one of a phase, 0 to 10% by volume of a B-rich phase, 0.1 to 10% by volume of an oxide of R and unavoidable impurities, nitride, hydroxide, or a mixture thereof; Composed of a composite.

得られた焼結磁石体(焼結ブロック)は所定形状に研削した後、本発明である磁石形態とするために、以下に示す吸収処理を施される。前述したように、本発明の磁石はR2成分及びフッ素原子を吸収させることで得られる。この場合、R2のフッ化物が使用できるが、R2のフッ化物はR2の金属、特にR2の金属薄膜と比較して化学的に安定であり、微細な粉末にしても化学変化を起こさない。更に、粉末にすることで、スパッタのような特殊な装置を必要とせずに磁石体への供給が可能である。更に、作製時に特に清浄な雰囲気も必要としない、即ちグローブボックスのような特殊で作業性の低い装置を必要としないことからも本発明の磁石が高い生産性を持って製造できることがわかる。 After the obtained sintered magnet body (sintered block) is ground into a predetermined shape, the following absorption treatment is performed in order to obtain a magnet according to the present invention. As described above, the magnet of the present invention can be obtained by absorbing the R 2 component and fluorine atoms. In this case, can be used fluoride of R 2 is, fluoride R 2 is R 2 metal, chemically stable and in particular compared to the metal thin film R 2, a chemical change in the fine powder Do not wake up. Furthermore, the powder can be supplied to the magnet body without requiring a special device such as sputtering. Furthermore, it can be seen that the magnet of the present invention can be manufactured with high productivity because it does not require a particularly clean atmosphere during production, that is, does not require a special and low workability device such as a glove box.

一例として、R2のフッ化物を含む粉末をアルコ−ルなどの液体と混合してスラリーとしたものを磁石表面に付着させ、液体を蒸発させた後に粉末に囲まれた状態の磁石を真空あるいはAr、He等の不活性ガス雰囲気中で焼結温度(Tsと称する)以下の温度、好ましくは200〜(Ts−5)℃、特に250〜(Ts−10)℃で、0.5〜100時間、特に1〜50時間熱処理する。この処理によりR2及びフッ素は、磁石表面から磁石内に吸収され、磁石内に存在していたR1の酸化物はFと反応して酸フッ化物へと化学変化する。 As an example, a slurry containing a powder containing R 2 fluoride mixed with a liquid such as alcohol is adhered to the surface of the magnet, and after the liquid is evaporated, the magnet surrounded by the powder is evacuated or vacuumed. A temperature equal to or lower than the sintering temperature (referred to as T s ) in an inert gas atmosphere such as Ar or He, preferably 200 to (T s −5) ° C., particularly 250 to (T s −10) ° C. Heat treatment is performed for 5 to 100 hours, particularly 1 to 50 hours. By this treatment, R 2 and fluorine are absorbed into the magnet from the magnet surface, and the oxide of R 1 present in the magnet reacts with F to chemically change to oxyfluoride.

なお、磁石内に存在するRの酸フッ化物とは、好ましくはROFであるが、これ以外のROmn(m、nは任意の正数)や、金属元素によりRの一部を置換したあるいは安定化されたもの等、本発明の効果を達成することができるRと酸素とフッ素を含む酸フッ化物を指す。 The oxyfluoride of R present in the magnet is preferably ROF, but a part of R is replaced by other RO m F n (m and n are arbitrary positive numbers) or metal elements. It refers to an oxyfluoride containing R, oxygen, and fluorine that can achieve the effects of the present invention, such as those that have been made or stabilized.

この時、磁石体内に吸収されるF量は、用いる粉末の組成、粒度、処理時に磁石表面を囲む空間内に存在させる割合、磁石の比表面積、処理温度・時間によって変化するが、0.01〜4原子%、特に0.05〜3.5原子%であることが好ましいが、特に磁石体の結晶粒界部に存在する円相当径が1μm以上の該酸フッ化物粒子の存在比率を1mm2当たり2,000個以上、特に3,000個以上とする点から0.02〜3.5原子%であることがより好ましく、更に好ましくは0.05〜3.5原子%であり、このため磁石体表面にFを0.03〜30mg/cm2、特に0.15〜15mg/cm2供給、吸収させることが好ましい。 At this time, the amount of F absorbed in the magnet body varies depending on the composition of the powder used, the particle size, the ratio of the powder to be present in the space surrounding the magnet surface during processing, the specific surface area of the magnet, and the processing temperature / time. It is preferable that the content ratio of the oxyfluoride particles having an equivalent circle diameter of 1 μm or more present at the crystal grain boundary portion of the magnet body is 1 mm. It is more preferably 0.02 to 3.5 atomic%, more preferably 0.05 to 3.5 atomic%, from the point of 2,000 or more per 2 , particularly 3,000 or more, 0.03~30mg / cm 2 to F in the magnet body surface for, in particular 0.15~15mg / cm 2 supply, it is preferable to absorb.

なお、上述した通り、磁石体表面から少なくとも20μm以上の領域において、結晶粒界部に存在する円相当径が1μm以上の酸フッ化物の存在比率は、1平方ミリメートル当たり2,000個以上であるが、酸フッ化物が存在する領域の磁石体表面からの深さは磁石含有酸素濃度により制御することができる。かかる点から、磁石含有酸素濃度は0.04〜4原子%、より好ましくは0.04〜3.5原子%、更に好ましくは0.04〜3原子%とすることが推奨される。酸フッ化物が存在する領域の磁石体表面からの深さ、酸フッ化物の粒径及び酸フッ化物の存在比率が上記範囲外であると効果的に比電気抵抗を増大できないため好ましくない。   Note that, as described above, in the region of at least 20 μm or more from the surface of the magnet body, the abundance ratio of the oxyfluoride having an equivalent circle diameter of 1 μm or more present in the crystal grain boundary is 2,000 or more per square millimeter. However, the depth from the surface of the magnet body in the region where the oxyfluoride is present can be controlled by the magnet-containing oxygen concentration. From this point, it is recommended that the magnet-containing oxygen concentration be 0.04 to 4 atomic%, more preferably 0.04 to 3.5 atomic%, and still more preferably 0.04 to 3 atomic%. If the depth of the region where the oxyfluoride exists from the surface of the magnet body, the particle size of the oxyfluoride, and the abundance ratio of the oxyfluoride are outside the above ranges, the specific electrical resistance cannot be effectively increased, which is not preferable.

また、上記処理によりR2成分も粒界近傍に濃化されるが、この場合、磁石体内に吸収されるR2成分の合計量は、0.005〜2原子%、より好ましくは0.01〜2原子%、更に好ましくは0.02〜1.5原子%であり、磁石体表面にR2成分を合計で0.07〜70mg/cm2、特に0.35〜35mg/cm2供給、吸収させることが好ましく、これにより表面から少なくとも10μm、特に13μm、とりわけ16μmの深さまで高R2濃度の連続三次元網目状の結晶粒界を確実に形成し得る。 The R 2 component is also concentrated in the vicinity of the grain boundary by the above treatment. In this case, the total amount of the R 2 component absorbed in the magnet body is 0.005 to 2 atomic%, more preferably 0.01. ˜2 atomic%, more preferably 0.02 to 1.5 atomic%, and a total of R 2 components on the surface of the magnet body of 0.07 to 70 mg / cm 2 , particularly 0.35 to 35 mg / cm 2 , Absorption is preferably performed, so that a continuous three-dimensional network grain boundary with a high R 2 concentration can be reliably formed from the surface to a depth of at least 10 μm, in particular 13 μm, in particular 16 μm.

以上のようにして得られた永久磁石材料は、高性能な永久磁石として、各種モータ、ピックアップのアクチュエータ等の用途に有効に使用することができる。   The permanent magnet material obtained as described above can be effectively used as a high-performance permanent magnet in applications such as various motors and pickup actuators.

以下、本発明の具体的態様について実施例及び比較例をもって詳述するが、本発明の内容はこれに限定されるものではない。   Hereinafter, although the specific aspect of this invention is explained in full detail with an Example and a comparative example, the content of this invention is not limited to this.

[実施例1、比較例1]
純度99質量%以上のNd、Al、Feメタルとフェロボロンを所定量秤量してAr雰囲気中で高周波溶解し銅製単ロールに注湯するストリップキャスト法により薄板状の合金とした。得られた合金の組成はNdが13.5原子%、Alが0.5原子%、Bが5.8原子%、Feが残部であり、これを合金Aと称する。これとは別に純度99質量%以上のNd、Tb、Fe、Co、Al、Cuメタルとフェロボロンを所定量秤量し、Ar雰囲気中で高周波溶解した後、平型に鋳込んでインゴット状の合金とした。得られた合金の組成はNdが20原子%、Tbが10原子%、Feが24原子%、Bが6原子%、Alが1原子%、Cuが2原子%、Coが残部であり、これを合金Bと称する。
[Example 1, Comparative Example 1]
A predetermined amount of Nd, Al, Fe metal and ferroboron having a purity of 99% by mass or more were weighed, melted by high frequency in an Ar atmosphere, and poured into a single copper roll to obtain a thin plate-like alloy. The composition of the resulting alloy is 13.5 atomic% Nd, 0.5 atomic% Al, 5.8 atomic% B, and the balance Fe. Separately, Nd, Tb, Fe, Co, Al, Cu metal with a purity of 99% by mass or more and ferroboron are weighed in a predetermined amount, melted at high frequency in an Ar atmosphere, and then cast into a flat mold to form an ingot-like alloy. did. The composition of the resulting alloy is Nd 20 atom%, Tb 10 atom%, Fe 24 atom%, B 6 atom%, Al 1 atom%, Cu 2 atom%, and Co remaining. Is referred to as Alloy B.

合金Aは水素粉砕により、合金Bは窒素雰囲気中、ジョークラッシャー及びブラウンミルを用いて30メッシュ以下に粗粉砕された。   Alloy A was coarsely pulverized to 30 mesh or less using a jaw crusher and a brown mill in a nitrogen atmosphere by hydrogen pulverization.

続いて、合金A粉末を92質量%、合金B粉末を8質量%秤量して、混合した後、高圧窒素ガスを用いたジェットミルにて、微粉砕された。微粉末の質量中位粒径は4.1μmであった。この混合微粉末を窒素雰囲気下15kOeの磁界中で配向させながら、約1ton/cm2の圧力で成形した。次いで、この成形体はAr雰囲気の焼結炉内に投入され、1,060℃で2時間焼結し磁石ブロックを作製した。磁石ブロックはダイヤモンドカッターにより10×10×厚み2mmに全面研削加工された後、アルカリ溶液に次いで硝酸で洗浄して乾燥させた。各洗浄の前後には純水による洗浄工程が含まれている。 Subsequently, 92% by mass of alloy A powder and 8% by mass of alloy B powder were weighed and mixed, and then finely pulverized by a jet mill using high-pressure nitrogen gas. The mass median particle size of the fine powder was 4.1 μm. The mixed fine powder was molded at a pressure of about 1 ton / cm 2 while being oriented in a magnetic field of 15 kOe in a nitrogen atmosphere. Next, this compact was put into a sintering furnace in an Ar atmosphere and sintered at 1,060 ° C. for 2 hours to produce a magnet block. The magnet block was ground to 10 × 10 × 2 mm thickness by a diamond cutter, then washed with an alkaline solution and then dried with nitric acid. A cleaning process with pure water is included before and after each cleaning.

次に、平均粉末粒径が2μmのフッ化ディスプロシウムを質量分率50%でエタノールと混合し、スラリーとしたものを作製した。これを、スプレーにより上記磁石体全面に塗布した。この時のフッ化ディスプロシウムの供給量は3.3mg/cm2であった。磁石を自然乾燥させた後、これにAr雰囲気中800℃で10時間という条件で吸収処理を施し、更に500℃で1時間時効処理して急冷することで、本発明の磁石体を得た。これを磁石体M1と称する。比較のために研削加工後にフッ化ディスプロシウムを付着させずに熱処理を施した磁石体も作製した。これをP1と称する。 Next, dysprosium fluoride having an average powder particle size of 2 μm was mixed with ethanol at a mass fraction of 50% to prepare a slurry. This was applied to the entire surface of the magnet body by spraying. The supply amount of dysprosium fluoride at this time was 3.3 mg / cm 2 . After the magnet was naturally dried, it was subjected to an absorption treatment at 800 ° C. for 10 hours in an Ar atmosphere, and further subjected to an aging treatment at 500 ° C. for 1 hour to rapidly cool, thereby obtaining the magnet body of the present invention. This is referred to as a magnet body M1. For comparison, a magnet body that was heat-treated without attaching dysprosium fluoride after grinding was also produced. This is referred to as P1.

磁石体M1、P1の磁気特性を表2に示した。また、磁石組成を表3に示した。フッ化ディスプロシウムの吸収処理を施していない磁石(P1)の保磁力に対して本発明による磁石は425kAm-1の保磁力増大が認められる。また、残留磁束密度の低下は5mTであった。EPMAによる磁石体M1、P1のDy組成像を図1に示す。磁石原料合金にはDyは含まれていないため、P1ではDyの存在を示す明るいコントラストは認められない[図1(b)]。一方、本発明のフッ化ディスプロシウムを用いて吸収処理した磁石M1では結晶粒界にのみDyが濃化しており、このDyの濃化した粒界相は磁石体表面より40μmの深さまで連続して三次元網目状に分布していた。図1(a)には、その表面付近におけるDyの組成像を示した。Dy吸収処理した磁石M1について、組成像の画像解析により平均Dy濃度と平均F濃度を算出し、磁石体表面からの深さ方向に対する濃度の変化を表1に示した。粒界に濃化しているDyとFは、磁石内部になるほど、その濃度が減少しているのがわかる。図2には、図1と同一視野におけるNd(図2(a))、O(図2(b))、F(図2(c))の組成像を示した。吸収されたフッ素は、磁石内に既に存在していた酸化ネオジムと反応し、酸フッ化ネオジムが生成していることがわかる。この場合、表面層には多数のNdOF粒子が存在しており、この領域における円相当径が1μm以上のNdOF粒子の分散頻度は5,000個/mm2、面積分率は4.7%であった。 Table 2 shows the magnetic characteristics of the magnet bodies M1 and P1. The magnet composition is shown in Table 3. The magnet according to the present invention has an increase in coercive force of 425 kAm −1 with respect to the coercive force of the magnet (P1) not subjected to the dysprosium fluoride absorption treatment. The decrease in residual magnetic flux density was 5 mT. FIG. 1 shows Dy composition images of the magnet bodies M1 and P1 by EPMA. Since the magnet raw material alloy does not contain Dy, no bright contrast indicating the presence of Dy is observed in P1 [FIG. 1 (b)]. On the other hand, in the magnet M1 that has been subjected to the absorption treatment using the dysprosium fluoride of the present invention, Dy is concentrated only at the crystal grain boundary, and the grain boundary phase in which this Dy is concentrated continues to a depth of 40 μm from the surface of the magnet body. It was distributed in a three-dimensional network. FIG. 1A shows a composition image of Dy near the surface. With respect to the magnet M1 subjected to the Dy absorption treatment, the average Dy concentration and the average F concentration were calculated by image analysis of the composition image, and changes in the concentration in the depth direction from the surface of the magnet body are shown in Table 1. It can be seen that the concentration of Dy and F concentrated in the grain boundary decreases as the inside of the magnet is reached. FIG. 2 shows composition images of Nd (FIG. 2A), O (FIG. 2B), and F (FIG. 2C) in the same field of view as FIG. It can be seen that the absorbed fluorine reacts with neodymium oxide already present in the magnet to produce neodymium oxyfluoride. In this case, a large number of NdOF particles are present in the surface layer, the dispersion frequency of NdOF particles having an equivalent circle diameter of 1 μm or more in this region is 5,000 particles / mm 2 , and the area fraction is 4.7%. there were.

[実施例2、比較例2]
純度99質量%以上のNd、Pr、Co、Al、Feメタルとフェロボロンを所定量秤量してAr雰囲気中で高周波溶解し銅製単ロールに注湯するストリップキャスト法により薄板状の合金とした。得られた合金の組成はNdが11.5原子%、Prが2.0原子%、Coが1.0原子%、Alが0.5原子%、Bが5.8原子%、Feが残部であり、これを合金Aと称する。これとは別に純度99質量%以上のNd、Dy、Fe、Co、Al、Cuメタルとフェロボロンを所定量秤量し、Ar雰囲気中で高周波溶解した後、平型に鋳込んでインゴット状の合金とした。得られた合金の組成はNdが20原子%、Dyが10原子%、Feが24原子%、Bが6原子%、Alが1原子%、Cuが2原子%、Coが残部であり、これを合金Bと称する。
[Example 2, Comparative Example 2]
A predetermined amount of Nd, Pr, Co, Al, Fe metal and ferroboron having a purity of 99% by mass or more were weighed and melted at a high frequency in an Ar atmosphere to form a thin plate-like alloy by a strip casting method in which it was poured into a single copper roll. The composition of the resulting alloy is Nd 11.5 atomic%, Pr 2.0 atomic%, Co 1.0 atomic%, Al 0.5 atomic%, B 5.8 atomic%, Fe remaining This is referred to as Alloy A. Separately, Nd, Dy, Fe, Co, Al, Cu metal with a purity of 99% by mass or more and ferroboron are weighed in predetermined amounts, melted at a high frequency in an Ar atmosphere, and then cast into a flat mold to obtain an ingot-like alloy. did. The composition of the resulting alloy is Nd 20 atom%, Dy 10 atom%, Fe 24 atom%, B 6 atom%, Al 1 atom%, Cu 2 atom%, and Co remaining. Is referred to as Alloy B.

合金Aは水素粉砕により、合金Bは窒素雰囲気中、ジョークラッシャー及びブラウンミルを用いて30メッシュ以下に粗粉砕された。   Alloy A was coarsely pulverized to 30 mesh or less using a jaw crusher and a brown mill in a nitrogen atmosphere by hydrogen pulverization.

続いて、合金A粉末を92質量%、合金B粉末を8質量%秤量して、混合した後、高圧窒素ガスを用いたジェットミルにて、微粉砕された。微粉末の質量中位粒径は3.9μmであった。この混合微粉末を窒素雰囲気下15kOeの磁界中で配向させながら、約1ton/cm2の圧力で成形した。次いで、この成形体はAr雰囲気の焼結炉内に投入され、1,050℃で2時間焼結し磁石ブロックを作製した。磁石ブロックはダイヤモンドカッターにより10×10×厚み3mmに全面研削加工された後、アルカリ溶液に次いで硝酸で洗浄して乾燥させた。各洗浄の前後には純水による洗浄工程が含まれている。 Subsequently, 92% by mass of alloy A powder and 8% by mass of alloy B powder were weighed and mixed, and then finely pulverized by a jet mill using high-pressure nitrogen gas. The mass median particle size of the fine powder was 3.9 μm. The mixed fine powder was molded at a pressure of about 1 ton / cm 2 while being oriented in a magnetic field of 15 kOe in a nitrogen atmosphere. Next, this compact was put into a sintering furnace in an Ar atmosphere and sintered at 1,050 ° C. for 2 hours to produce a magnet block. The magnet block was ground to 10 × 10 × 3 mm in thickness with a diamond cutter, then washed with nitric acid and then nitric acid and dried. A cleaning process with pure water is included before and after each cleaning.

次に、平均粉末粒径が2μmのフッ化テルビウムを質量分率50%でエタノールと混合し、スラリーとしたものを作製した。これを、スプレーにより上記磁石体全面に塗布し、磁石を自然乾燥させた。この時のフッ化テルビウムの供給量は5.1mg/cm2であった。これにAr雰囲気中800℃で15時間という条件で吸収処理を施し、更に500℃で1時間時効処理して急冷することで、本発明の磁石体を得た。これを磁石体M2と称する。比較のために研削加工後にフッ化テルビウムを付着させずに熱処理を施した磁石体も作製した。これをP2と称する。 Next, terbium fluoride having an average powder particle size of 2 μm was mixed with ethanol at a mass fraction of 50% to prepare a slurry. This was applied to the entire surface of the magnet body by spraying, and the magnet was naturally dried. At this time, the supply amount of terbium fluoride was 5.1 mg / cm 2 . This was subjected to an absorption treatment under conditions of 800 ° C. for 15 hours in an Ar atmosphere, and further subjected to an aging treatment at 500 ° C. for 1 hour, followed by rapid cooling to obtain a magnet body of the present invention. This is referred to as a magnet body M2. For comparison, a magnet body that was heat-treated without attaching terbium fluoride after grinding was also produced. This is referred to as P2.

磁石体M2、P2の磁気特性を表2に示した。また、磁石組成を表3に示した。フッ化テルビウムの吸収処理を施していない磁石(P2)の保磁力に対して本発明による磁石は760kAm-1の保磁力増大が認められる。また、残留磁束密度の低下は5mTであった。EPMAによる磁石体M2のTb及びFの組成像は実施例1におけるDy及びFと同様な形態であった。EPMAにより実施例の磁石体の表面層における各元素の濃度分布を測定した結果、実施例1と同様な形態で多数のROF粒子が存在していた。 Table 2 shows the magnetic characteristics of the magnet bodies M2 and P2. The magnet composition is shown in Table 3. The magnet according to the present invention has an increased coercive force of 760 kAm −1 compared to the coercive force of the magnet (P2) not subjected to the terbium fluoride absorption treatment. The decrease in residual magnetic flux density was 5 mT. The composition image of Tb and F of the magnet body M2 by EPMA was in the same form as Dy and F in Example 1. As a result of measuring the concentration distribution of each element in the surface layer of the magnet body of the example by EPMA, a large number of ROF particles were present in the same form as in Example 1.

[実施例3、比較例3]
純度99質量%以上のNd、Al、Cu、Feメタルとフェロボロンを所定量秤量してAr雰囲気中で高周波溶解し銅製単ロールに注湯するストリップキャスト法により薄板状の合金とした。得られた合金の組成はNdが13.2原子%、Alが0.5原子%、Cuが0.3原子%、Bが5.8原子%、Feが残部であった。
[Example 3, Comparative Example 3]
A predetermined amount of Nd, Al, Cu, Fe metal and ferroboron with a purity of 99% by mass or more was weighed, melted at high frequency in an Ar atmosphere, and poured into a single copper roll to obtain a thin plate-like alloy. The composition of the obtained alloy was Nd of 13.2 atomic%, Al of 0.5 atomic%, Cu of 0.3 atomic%, B of 5.8 atomic%, and the balance of Fe.

薄板状の合金は水素粉砕により30メッシュ以下に粗粉砕された後、高圧窒素ガスを用いたジェットミルにて、微粉砕された。微粉末の質量中位粒径は4.4μmであった。この混合微粉末を窒素雰囲気下15kOeの磁界中で配向させながら、約1ton/cm2の圧力で成形した。次いで、この成形体はAr雰囲気の焼結炉内に投入され、1,060℃で2時間焼結し磁石ブロックを作製した。磁石ブロックはダイヤモンドカッターにより3×3×厚み3mmに全面研削加工された後、アルカリ溶液に次いで硝酸で洗浄して乾燥させた。各洗浄の前後には純水による洗浄工程が含まれている。 The thin plate-like alloy was coarsely pulverized to 30 mesh or less by hydrogen pulverization, and then finely pulverized by a jet mill using high-pressure nitrogen gas. The mass median particle size of the fine powder was 4.4 μm. The mixed fine powder was molded at a pressure of about 1 ton / cm 2 while being oriented in a magnetic field of 15 kOe in a nitrogen atmosphere. Next, this compact was put into a sintering furnace in an Ar atmosphere and sintered at 1,060 ° C. for 2 hours to produce a magnet block. The magnet block was ground to 3 × 3 × thickness 3 mm with a diamond cutter, then washed with an alkaline solution and then dried with nitric acid. A cleaning process with pure water is included before and after each cleaning.

次に、平均粉末粒径が2μmのフッ化テルビウムを質量分率50%で純水と混合したスラリーを作製した。これに超音波を加えながら上記磁石体を1分間浸し、引き上げた後直ちに熱風により乾燥させた。この時のフッ化テルビウムの供給量は1.8mg/cm2であった。フッ化テルビウム粉末に囲まれた磁石体にAr雰囲気中900℃で2時間という条件で吸収処理を施し、更に500℃で1時間時効処理して急冷することで、本発明の磁石体を得た。これを磁石体M3と称する。比較のために研削加工後にフッ化テルビウムを付着させずに熱処理を施した磁石体も作製した。これをP3と称する。 Next, a slurry in which terbium fluoride having an average powder particle size of 2 μm was mixed with pure water at a mass fraction of 50% was prepared. The magnet body was soaked for 1 minute while applying ultrasonic waves to it, and immediately dried and then dried with hot air. At this time, the supply amount of terbium fluoride was 1.8 mg / cm 2 . The magnet body surrounded by the terbium fluoride powder was subjected to an absorption treatment at 900 ° C. for 2 hours in an Ar atmosphere, and further subjected to an aging treatment at 500 ° C. for 1 hour to rapidly cool, thereby obtaining the magnet body of the present invention. . This is referred to as a magnet body M3. For comparison, a magnet body that was heat-treated without attaching terbium fluoride after grinding was also produced. This is referred to as P3.

磁石体M3、P3の磁気特性を表2に示した。また、磁石組成を表3に示した。フッ化テルビウムの吸収処理を施していない磁石(P3)の保磁力に対して本発明による磁石は730kAm-1の保磁力増大が認められる。また、残留磁束密度の低下は5mTであった。EPMAによる磁石体M3のTb及びFの組成像は実施例1におけるDy及びFと同様な形態であった。EPMAにより実施例の磁石体の表面層における各元素の濃度分布を測定した結果、実施例1と同様な形態で多数のROF粒子が存在していた。 Table 2 shows the magnetic characteristics of the magnet bodies M3 and P3. The magnet composition is shown in Table 3. The magnet according to the present invention has an increase in coercive force of 730 kAm −1 with respect to the coercive force of the magnet (P3) not subjected to terbium fluoride absorption treatment. The decrease in residual magnetic flux density was 5 mT. The composition images of Tb and F of the magnet body M3 by EPMA were in the same form as Dy and F in Example 1. As a result of measuring the concentration distribution of each element in the surface layer of the magnet body of the example by EPMA, a large number of ROF particles were present in the same form as in Example 1.

[実施例4、比較例4]
純度99質量%以上のNd、Pr、Al、Cu、Zr、Feメタルとフェロボロンを所定量秤量してAr雰囲気中で高周波溶解し銅製単ロールに注湯するストリップキャスト法により薄板状の合金とした。得られた合金の組成はNdが11.0原子%、Prが2.2原子%、Alが0.5原子%、Cuが0.3原子%、Zrが0.2原子%、Bが6.0原子%、Feが残部であった。
[Example 4, Comparative Example 4]
A predetermined amount of Nd, Pr, Al, Cu, Zr, Fe metal and ferroboron with a purity of 99% by mass or more is weighed, melted at high frequency in an Ar atmosphere, and poured into a single copper roll to form a thin plate-like alloy. . The composition of the alloy obtained is as follows: Nd is 11.0 atomic%, Pr is 2.2 atomic%, Al is 0.5 atomic%, Cu is 0.3 atomic%, Zr is 0.2 atomic%, and B is 6 0.0 atomic%, Fe was the balance.

薄板状の合金は水素粉砕により30メッシュ以下に粗粉砕された後、高圧窒素ガスを用いたジェットミルにて、微粉砕された。微粉末の質量中位粒径は3.8μmであった。この微粉末を窒素雰囲気下15kOeの磁界中で配向させながら、約1ton/cm2の圧力で成形した。次いで、この成形体はAr雰囲気の焼結炉内に投入され、1,070℃で2時間焼結し磁石ブロックを作製した。磁石ブロックはダイヤモンドカッターにより5×5×厚み2mmに全面研削加工された後、アルカリ溶液に次いで硝酸で洗浄して乾燥させた。各洗浄の前後には純水による洗浄工程が含まれている。 The thin plate-like alloy was coarsely pulverized to 30 mesh or less by hydrogen pulverization, and then finely pulverized by a jet mill using high-pressure nitrogen gas. The mass median particle size of the fine powder was 3.8 μm. The fine powder was molded at a pressure of about 1 ton / cm 2 while being oriented in a magnetic field of 15 kOe in a nitrogen atmosphere. Next, this compact was put into a sintering furnace in an Ar atmosphere and sintered at 1,070 ° C. for 2 hours to produce a magnet block. The magnet block was ground to 5 × 5 × 2 mm in thickness with a diamond cutter, then washed with nitric acid and then nitric acid and dried. A cleaning process with pure water is included before and after each cleaning.

次に、フッ化テルビウムとフッ化ディスプロシウムと酸化ネオジムを質量分率で40%、30%、30%の割合で秤量・混合した。この混合粉末を質量分率50%でエタノールと混合したスラリーを作製した。フッ化テルビウム、フッ化ディスプロシウム、及び酸化ネオジムの平均粉末粒径は、それぞれ2μm、10μm、1μmであった。このスラリーに超音波を加えながら上記磁石体を1分間浸し、引き上げた後直ちに熱風により乾燥させた。この時のフッ化テルビウムとフッ化ディスプロシウムの供給量は2.9mg/cm2であった。上記混合粉末に囲まれた磁石体にAr雰囲気中850℃で8時間という条件で吸収処理を施し、更に500℃で1時間時効処理して急冷することで、本発明の磁石体を得た。これを磁石体M4と称する。比較のために研削加工後にフッ化テルビウム、フッ化ディスプロシウム及び酸化ネオジムを付着させずに熱処理を施した磁石体も作製した。これをP4と称する。 Next, terbium fluoride, dysprosium fluoride, and neodymium oxide were weighed and mixed at a mass fraction of 40%, 30%, and 30%. A slurry was prepared by mixing this mixed powder with ethanol at a mass fraction of 50%. The average powder particle sizes of terbium fluoride, dysprosium fluoride, and neodymium oxide were 2 μm, 10 μm, and 1 μm, respectively. The magnet body was immersed for 1 minute while applying ultrasonic waves to the slurry, and immediately dried and then dried with hot air. At this time, the supply amounts of terbium fluoride and dysprosium fluoride were 2.9 mg / cm 2 . The magnet body surrounded by the mixed powder was subjected to an absorption treatment in an Ar atmosphere at 850 ° C. for 8 hours, and further subjected to an aging treatment at 500 ° C. for 1 hour to rapidly cool, thereby obtaining the magnet body of the present invention. This is referred to as a magnet body M4. For comparison, a magnet body that was heat-treated without attaching terbium fluoride, dysprosium fluoride, and neodymium oxide after grinding was also produced. This is referred to as P4.

磁石体M4、P4の磁気特性を表2に示した。また、磁石組成を表3に示した。フッ化テルビウム及びフッ化ディスプロシウムの吸収処理を施していない磁石(P4)の保磁力に対して本発明による磁石は570kAm-1の保磁力増大が認められる。また、残留磁束密度の低下は5mTであった。EPMAにより実施例4の磁石体の表面層における各元素の濃度分布を測定した結果、実施例1と同様な形態で多数のROF粒子が存在していた。 Table 2 shows the magnetic properties of the magnet bodies M4 and P4. The magnet composition is shown in Table 3. The magnet according to the present invention has an increase in coercive force of 570 kAm −1 with respect to the coercive force of the magnet (P4) not subjected to the absorption treatment of terbium fluoride and dysprosium fluoride. The decrease in residual magnetic flux density was 5 mT. As a result of measuring the concentration distribution of each element in the surface layer of the magnet body of Example 4 by EPMA, a large number of ROF particles were present in the same form as in Example 1.

[実施例5〜9、比較例5〜9]
純度99質量%以上のNd、Pr、Al、Cu、Ta、Sn、Ga、Mn、Hf、Feメタルとフェロボロンを所定量秤量してAr雰囲気中で高周波溶解し銅製単ロールに注湯するストリップキャスト法により薄板状の合金とした。得られた合金の組成はNdが11.0原子%、Prが2.2原子%、Alが0.5原子%、Cuが0.3原子%、Bが6.0原子%、M’が0.7原子%、Feが残部であった。なお、M’はTa、Sn、Ga、Mn、Hfのいずれか1つである。
[Examples 5-9, Comparative Examples 5-9]
A strip cast that weighs a predetermined amount of Nd, Pr, Al, Cu, Ta, Sn, Ga, Mn, Hf, Fe metal and ferroboron with a purity of 99% by mass or more, melts them in high frequency in an Ar atmosphere, and pours them into a single copper roll A thin plate alloy was obtained by the method. The composition of the obtained alloy is that Nd is 11.0 atomic%, Pr is 2.2 atomic%, Al is 0.5 atomic%, Cu is 0.3 atomic%, B is 6.0 atomic%, and M ′ is 0.7 atomic%, Fe was the balance. M ′ is any one of Ta, Sn, Ga, Mn, and Hf.

薄板状の合金は水素粉砕により30メッシュ以下に粗粉砕された後、高圧窒素ガスを用いたジェットミルにて、微粉砕された。微粉末の質量中位粒径は3.9〜4.3μmであった。この微粉末を窒素雰囲気下15kOeの磁界中で配向させながら、約1ton/cm2の圧力で成形した。次いで、この成形体はAr雰囲気の焼結炉内に投入され、1,060℃で2時間焼結し磁石ブロックを作製した。磁石ブロックはダイヤモンドカッターにより20×20×厚み3mmに全面研削加工された後、アルカリ溶液に次いでクエン酸で洗浄して乾燥させた。各洗浄の前後には純水による洗浄工程が含まれている。 The thin plate-like alloy was coarsely pulverized to 30 mesh or less by hydrogen pulverization, and then finely pulverized by a jet mill using high-pressure nitrogen gas. The mass median particle size of the fine powder was 3.9 to 4.3 μm. The fine powder was molded at a pressure of about 1 ton / cm 2 while being oriented in a magnetic field of 15 kOe in a nitrogen atmosphere. Next, this compact was put into a sintering furnace in an Ar atmosphere and sintered at 1,060 ° C. for 2 hours to produce a magnet block. The magnet block was ground to 20 × 20 × 3 mm in thickness with a diamond cutter, then washed with an alkaline solution and then citric acid and dried. A cleaning process with pure water is included before and after each cleaning.

次に、フッ化テルビウムを質量分率50%でエタノールと混合したスラリーを作製した。フッ化テルビウムの平均粉末粒径は2μmであった。このスラリーに超音波を加えながら上記磁石体を1分間浸し、引き上げた後直ちに熱風により乾燥させた。この時のフッ化テルビウムの供給量は2.1mg/cm2であった。上記微粉末に囲まれた磁石体にAr雰囲気中800℃で8時間という条件で吸収処理を施し、更に500℃で1時間時効処理して急冷することで、本発明の磁石体を得た。これを、M’=Ta、Sn、Ga、Mn、Hfの順で磁石体M5〜9と称する。比較のために研削加工後にフッ化テルビウムを付着させずに熱処理を施した磁石体も作製した。これも同様にP5〜9と称する。 Next, a slurry was prepared by mixing terbium fluoride with ethanol at a mass fraction of 50%. The average powder particle size of terbium fluoride was 2 μm. The magnet body was immersed for 1 minute while applying ultrasonic waves to the slurry, and immediately dried and then dried with hot air. At this time, the supply amount of terbium fluoride was 2.1 mg / cm 2 . The magnet body surrounded by the fine powder was subjected to an absorption treatment at 800 ° C. for 8 hours in an Ar atmosphere, and further subjected to an aging treatment at 500 ° C. for 1 hour to rapidly cool, thereby obtaining the magnet body of the present invention. These are referred to as magnet bodies M5 to M9 in the order of M ′ = Ta, Sn, Ga, Mn, and Hf. For comparison, a magnet body that was heat-treated without attaching terbium fluoride after grinding was also produced. This is also referred to as P5-9.

磁石体M5〜9、P5〜9の磁気特性を表2に示した。また、磁石組成を表3に示した。フッ化テルビウムの吸収処理を施していない磁石の保磁力に対して本発明による磁石は400〜800kAm-1の保磁力増大が認められる。また、残留磁束密度の低下は概ね5mTであった。EPMAにより実施例の磁石体の表面層における各元素の濃度分布を測定した結果、実施例1と同様な形態で多数のROF粒子が存在していた。 The magnetic properties of the magnet bodies M5 to 9 and P5 to 9 are shown in Table 2. The magnet composition is shown in Table 3. The magnet according to the present invention has an increase in coercive force of 400 to 800 kAm −1 with respect to the coercive force of the magnet not subjected to the terbium fluoride absorption treatment. The decrease in residual magnetic flux density was approximately 5 mT. As a result of measuring the concentration distribution of each element in the surface layer of the magnet body of the example by EPMA, a large number of ROF particles were present in the same form as in Example 1.

注1:式(1)中のMに相当する元素の合計量 Note 1: Total amount of elements corresponding to M in formula (1)

分析値は、希土類元素については、実施例、比較例と同等の試料を王水によって全量溶かし、ICP法により求めた。酸素については不活性ガス融解赤外吸収測定法で、フッ素については水蒸気蒸留−アルフッソン比色法で求めた。   Analytical values were determined by the ICP method for rare earth elements by dissolving all the same samples as in Examples and Comparative Examples with aqua regia. Oxygen was determined by an inert gas melting infrared absorption measurement method, and fluorine was determined by a steam distillation-Alfusson colorimetric method.

実施例1において作製された磁石体M1のDy組成像(a)及び研削加工と熱処理のみの磁石体P1のDy組成像(b)を示した図である。It is the figure which showed the Dy composition image (a) of the magnet body M1 produced in Example 1, and the Dy composition image (b) of the magnet body P1 only of a grinding process and heat processing. 実施例1において作製された磁石体M1のNd組成像(a)、O組成像(b)、及びF組成像(c)を示した図である。It is the figure which showed the Nd composition image (a), O composition image (b), and F composition image (c) of the magnet body M1 produced in Example 1. FIG.

Claims (6)

1 a2 bcdefg組成(R1はSc及びYを含み、Tb及びDyを除く希土類元素から選ばれる1種又は2種以上、R2はTb及びDyから選ばれる1種又は2種、TはFe及びCoから選ばれる1種又は2種、AはB及びCから選ばれる1種又は2種、MはAl、Cu、Zn、In、Si、P、S、Ti、V、Cr、Mn、Ni、Ga、Ge、Zr、Nb、Mo、Pd、Ag、Cd、Sn、Sb、Hf、Ta、Wの中から選ばれる1種又は2種以上、a〜gは合金の原子%で、10≦a+b≦15、3≦d≦15、0.01≦e≦4、0.04≦f≦4、0.01≦g≦11、残部がc)を有する焼結磁石体であって、その構成元素であるF及びR2が磁石体中心より磁石体表面に向かって平均的に含有濃度が濃くなるように分布し、かつ、R2/(R1+R2)の濃度が(R1,R2214A正方晶からなる主相結晶粒中のR2/(R1+R2)濃度より平均的に濃い結晶粒界が磁石表面から少なくとも10μmの深さまで連続した三次元網目状の形態をなしていることを特徴とする希土類永久磁石。 R 1 a R 2 b T c A d F e O f M g composition (R 1 includes Sc and Y, 1 or 2 or more selected from rare earth elements excluding Tb and Dy, R 2 is Tb and Dy 1 or 2 selected from T, 1 or 2 selected from Fe and Co, A is 1 or 2 selected from B and C, M is Al, Cu, Zn, In, Si, P S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, W or one or more selected from a to g are atomic% of the alloy, 10 ≦ a + b ≦ 15, 3 ≦ d ≦ 15, 0.01 ≦ e ≦ 4, 0.04 ≦ f ≦ 4, 0.01 ≦ g ≦ 11, the balance being c) a sintered magnet body having, as the F and R 2 is a constituent element thereof becomes darker on average contain a concentration towards the magnet body surface than the magnet body center And cloth, and the average than the concentration is (R 1, R 2) 2 T 14 A R in the main phase crystal grains consisting of tetragonal 2 / (R 1 + R 2 ) a concentration of R 2 / (R 1 + R 2) A rare earth permanent magnet characterized in that a deep grain boundary has a continuous three-dimensional network shape from the magnet surface to a depth of at least 10 μm. 結晶粒界部の磁石体表面より少なくとも20μmの深さ領域にまで、結晶粒界部に(R1,R2)の酸フッ化物が存在し、該領域において円相当径が1μm以上の該酸フッ化物粒子が1平方ミリメ−トル当たり2,000個以上の割合で分散し、かつ当該酸フッ化物が面積分率で1%以上を占めていることを特徴とする請求項1記載の希土類永久磁石。 (R 1 , R 2 ) oxyfluoride is present in the crystal grain boundary part to a depth region of at least 20 μm from the surface of the magnet body in the crystal grain boundary part, and the acid having an equivalent circle diameter of 1 μm or more in the region. 2. The rare earth permanent material according to claim 1, wherein the fluoride particles are dispersed at a rate of 2,000 or more per square millimeter and the oxyfluoride occupies 1% or more in area fraction. magnet. 結晶粒界部に存在する酸フッ化物に含まれるNd及び/又はPrのR1+R2に対する原子分率が、該酸フッ化物及びR3の酸化物(R3はSc及びYを含む希土類元素から選ばれる1種あるいは2種以上)を除いた結晶粒界部におけるNd及び/又はPrのR1+R2に対する原子分率よりも高いことを特徴とする請求項1又は2記載の希土類永久磁石。 Rare earth elements including R 1 + R 2 against atomic fraction of Nd contained in the oxyfluoride is present in the crystal grain boundaries and / or Pr is, oxides of the acid fluoride and R 3 a (R 3 are Sc and Y 3. The rare earth permanent magnet according to claim 1, wherein Nd and / or Pr is higher than the atomic fraction of R 1 + R 2 in the grain boundary excluding one or more selected from the above. . 1がNd及び/又はPrを10原子%以上含有することを特徴とする請求項1乃至3のいずれか1項に記載の希土類永久磁石。 The rare earth permanent magnet according to any one of claims 1 to 3, wherein R 1 contains Nd and / or Pr in an amount of 10 atomic% or more. TがFeを60原子%以上含有することを特徴とする請求項1乃至4のいずれか1項に記載の希土類永久磁石。   5. The rare earth permanent magnet according to claim 1, wherein T contains 60 atomic% or more of Fe. AがBを80原子%以上含有することを特徴とする請求項1乃至5のいずれか1項に記載の希土類永久磁石。   The rare earth permanent magnet according to any one of claims 1 to 5, wherein A contains 80 atomic% or more of B.
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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008147634A (en) * 2006-11-17 2008-06-26 Shin Etsu Chem Co Ltd Manufacturing method of rare earth permanent magnet
WO2008123251A1 (en) 2007-03-27 2008-10-16 Hitachi Metals, Ltd. Permanent magnet type rotator and process for producing the same
WO2008139559A1 (en) 2007-05-02 2008-11-20 Hitachi Metals, Ltd. R-t-b sintered magnet
WO2008139556A1 (en) 2007-05-02 2008-11-20 Hitachi Metals, Ltd. R-t-b sintered magnet
JP2009224413A (en) * 2008-03-13 2009-10-01 Inter Metallics Kk MANUFACTURING METHOD OF NdFeB SINTERED MAGNET
EP2141710A1 (en) 2008-07-04 2010-01-06 Daido Tokushuko Kabushiki Kaisha Rare earth magnet and production process thereof
US7880357B2 (en) 2008-09-29 2011-02-01 Hitachi, Ltd. Sintered magnet and rotating machine equipped with the same
JP2011187734A (en) * 2010-03-09 2011-09-22 Tdk Corp Rare earth sintered magnet, and method for producing the same
US8350430B2 (en) 2008-07-30 2013-01-08 Hitachi, Ltd. Rotating machine with sintered magnet and method for producing sintered magnet
JP2013153172A (en) * 2013-02-21 2013-08-08 Inter Metallics Kk Manufacturing method of neodymium-iron-boron sintered magnet
JP5363314B2 (en) * 2007-05-01 2013-12-11 インターメタリックス株式会社 NdFeB-based sintered magnet manufacturing method
US8821649B2 (en) 2010-03-30 2014-09-02 Hitachi, Ltd. Magnetic material and motor using the same
US8823478B2 (en) 2010-03-30 2014-09-02 Tdk Corporation Rare earth sintered magnet, method for producing same, motor and automobile
US9154004B2 (en) 2010-03-04 2015-10-06 Tdk Corporation Rare earth sintered magnet and motor
JP2016122861A (en) * 2015-08-28 2016-07-07 ティアンヘ (パオトウ) アドヴァンスト テック マグネット カンパニー リミテッド Manufacturing method for rare earth permanent magnet material
JP2017224831A (en) * 2013-03-18 2017-12-21 インターメタリックス株式会社 RFeB MAGNET MANUFACTURING METHOD, RFeB MAGNET, AND COATING MATERIAL FOR GRAIN BOUNDARY DIFFUSION TREATMENT
JP2020155541A (en) * 2019-03-19 2020-09-24 Tdk株式会社 R-t-b based permanent magnet

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63255902A (en) * 1987-04-13 1988-10-24 Hitachi Metals Ltd R-b-fe sintered magnet and manufacture thereof
JPH06244011A (en) * 1992-12-26 1994-09-02 Sumitomo Special Metals Co Ltd Corrosion-resistant rare earth magnet and manufacture thereof
JP2001068317A (en) * 1999-08-31 2001-03-16 Shin Etsu Chem Co Ltd Nd-Fe-B SINTERED MAGNET AND ITS MANUFACTURING METHOD
WO2004114333A1 (en) * 2003-06-18 2004-12-29 Japan Science And Technology Agency Rare earth - iron - boron based magnet and method for production thereof
JP2006066870A (en) * 2004-07-28 2006-03-09 Hitachi Ltd Rare-earth magnet
WO2006064848A1 (en) * 2004-12-16 2006-06-22 Japan Science And Technology Agency Nd-Fe-B MAGNET WITH MODIFIED GRAIN BOUNDARY AND PROCESS FOR PRODUCING THE SAME
JP2006238604A (en) * 2005-02-25 2006-09-07 Hitachi Ltd Permanent magnet rotating machine

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63255902A (en) * 1987-04-13 1988-10-24 Hitachi Metals Ltd R-b-fe sintered magnet and manufacture thereof
JPH06244011A (en) * 1992-12-26 1994-09-02 Sumitomo Special Metals Co Ltd Corrosion-resistant rare earth magnet and manufacture thereof
JP2001068317A (en) * 1999-08-31 2001-03-16 Shin Etsu Chem Co Ltd Nd-Fe-B SINTERED MAGNET AND ITS MANUFACTURING METHOD
WO2004114333A1 (en) * 2003-06-18 2004-12-29 Japan Science And Technology Agency Rare earth - iron - boron based magnet and method for production thereof
JP2006066870A (en) * 2004-07-28 2006-03-09 Hitachi Ltd Rare-earth magnet
WO2006064848A1 (en) * 2004-12-16 2006-06-22 Japan Science And Technology Agency Nd-Fe-B MAGNET WITH MODIFIED GRAIN BOUNDARY AND PROCESS FOR PRODUCING THE SAME
JP2006238604A (en) * 2005-02-25 2006-09-07 Hitachi Ltd Permanent magnet rotating machine

Cited By (27)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008147634A (en) * 2006-11-17 2008-06-26 Shin Etsu Chem Co Ltd Manufacturing method of rare earth permanent magnet
WO2008123251A1 (en) 2007-03-27 2008-10-16 Hitachi Metals, Ltd. Permanent magnet type rotator and process for producing the same
US8801870B2 (en) 2007-05-01 2014-08-12 Intermetallics Co., Ltd. Method for making NdFeB sintered magnet
JP5363314B2 (en) * 2007-05-01 2013-12-11 インターメタリックス株式会社 NdFeB-based sintered magnet manufacturing method
EP2034493A4 (en) * 2007-05-02 2009-07-22 Hitachi Metals Ltd R-t-b sintered magnet
KR101378090B1 (en) * 2007-05-02 2014-03-27 히다찌긴조꾸가부시끼가이사 R-t-b sintered magnet
EP2034493A1 (en) * 2007-05-02 2009-03-11 Hitachi Metals, Ltd. R-t-b sintered magnet
EP2077567A4 (en) * 2007-05-02 2009-07-22 Hitachi Metals Ltd R-t-b sintered magnet
EP2077567A1 (en) * 2007-05-02 2009-07-08 Hitachi Metals, Ltd. R-t-b sintered magnet
WO2008139559A1 (en) 2007-05-02 2008-11-20 Hitachi Metals, Ltd. R-t-b sintered magnet
KR101378089B1 (en) * 2007-05-02 2014-03-27 히다찌긴조꾸가부시끼가이사 R-t-b sintered magnet
WO2008139556A1 (en) 2007-05-02 2008-11-20 Hitachi Metals, Ltd. R-t-b sintered magnet
JP2009224413A (en) * 2008-03-13 2009-10-01 Inter Metallics Kk MANUFACTURING METHOD OF NdFeB SINTERED MAGNET
EP2141710A1 (en) 2008-07-04 2010-01-06 Daido Tokushuko Kabushiki Kaisha Rare earth magnet and production process thereof
US8002906B2 (en) 2008-07-04 2011-08-23 Daido Tokushuko Kabushiki Kaisha Rare earth magnet and production process thereof
US8350430B2 (en) 2008-07-30 2013-01-08 Hitachi, Ltd. Rotating machine with sintered magnet and method for producing sintered magnet
US7880357B2 (en) 2008-09-29 2011-02-01 Hitachi, Ltd. Sintered magnet and rotating machine equipped with the same
US9154004B2 (en) 2010-03-04 2015-10-06 Tdk Corporation Rare earth sintered magnet and motor
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US8821649B2 (en) 2010-03-30 2014-09-02 Hitachi, Ltd. Magnetic material and motor using the same
US8823478B2 (en) 2010-03-30 2014-09-02 Tdk Corporation Rare earth sintered magnet, method for producing same, motor and automobile
JP2013153172A (en) * 2013-02-21 2013-08-08 Inter Metallics Kk Manufacturing method of neodymium-iron-boron sintered magnet
JP2017224831A (en) * 2013-03-18 2017-12-21 インターメタリックス株式会社 RFeB MAGNET MANUFACTURING METHOD, RFeB MAGNET, AND COATING MATERIAL FOR GRAIN BOUNDARY DIFFUSION TREATMENT
US10475561B2 (en) 2013-03-18 2019-11-12 Intermetallics Co., Ltd. RFeB system magnet production method, RFeB system magnet, and coating material for grain boundary diffusion treatment
JP2016122861A (en) * 2015-08-28 2016-07-07 ティアンヘ (パオトウ) アドヴァンスト テック マグネット カンパニー リミテッド Manufacturing method for rare earth permanent magnet material
JP2020155541A (en) * 2019-03-19 2020-09-24 Tdk株式会社 R-t-b based permanent magnet
JP7247687B2 (en) 2019-03-19 2023-03-29 Tdk株式会社 R-T-B system permanent magnet

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