JP2779794B2 - Manufacturing method of rare earth permanent magnet - Google Patents
Manufacturing method of rare earth permanent magnetInfo
- Publication number
- JP2779794B2 JP2779794B2 JP61111827A JP11182786A JP2779794B2 JP 2779794 B2 JP2779794 B2 JP 2779794B2 JP 61111827 A JP61111827 A JP 61111827A JP 11182786 A JP11182786 A JP 11182786A JP 2779794 B2 JP2779794 B2 JP 2779794B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- phase
- powder
- rare earth
- magnet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- 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
- H01F1/0571—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes
- H01F1/0575—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together
- H01F1/0577—Alloys characterised by their composition containing rare earth metals and magnetic transition metals, e.g. SmCo5 and IIIa elements, e.g. Nd2Fe14B in the form of particles, e.g. rapid quenched powders or ribbon flakes pressed, sintered or bonded together sintered
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は,Yを含む希土類元素（以下Ｒと略記する）
と,Fe,Bより成る金属間化合物及びＳ及び非磁性金属Ｍ
よりなるR2Fe14B−Ｍ系磁石材料を用いて，温度特性が
改良されたR2T14B−Ｍ系磁石とその製造方法に関するも
のである。
〔従来の技術〕
Ｒ・Fe・Ｂ系永久磁石の文献として特開昭59−46008
号公報や日本応用磁気学会第35回研究会資料（昭59年５
月）がある。またその温度特性改良材の文献として特開
昭59−64733号公報が挙げられる。
これらの文献に開示されているものは，いずれもR2T
14B相を主相とするＲ・Ｔ・Ｂ系合金粉末を普通の常圧
焼結法により得る方法であり，それらにおいては，所定
の組成から成る合金を溶解して粉砕し，それを磁場中で
成形した後,900〜1200℃の温度で焼結するものである。
更に詳しく説明すると，常圧焼結法によりＲ・Ｔ・Ｂ系
永久磁石を製造する場合，その緻密化は高Nd相（液相）
の出現に伴う液相焼結によって成される。即ち，焼結体
中には，磁性相であり主相とするR2T14B相，この他は非
磁性相であるＢ−rich相，酸化物相の他に，液相成分相
であるNd−rich相が存在する。一般に本系磁石合金で
は，これら各相の存在比に対応して，磁石特性（特にB
r,（BH）max）は大きく変化する。現状のプロセスによ
り得られる焼結体中には，これら非磁性相の体積構成比
は約10％以上である。
その他の製法としては，メルトスピニング法による超
急冷物質の焼鈍法（特開昭60−100402号），あるいは射
出成形やボンド磁石法（特開昭59−219904号）などがあ
る。
〔発明が解決しようとする問題点〕
常圧焼結方法の場合には製品に充分な緻密化を得るた
めには，液相成分を体積構成比で５％以上必要とするた
め，常圧焼結により得られる磁石特性には，限界があ
る。さらにＲ−Ｔ−Ｂ系の磁石の常圧焼結は900〜1200
℃という高温で行なわれるため，高温による変形などが
原因となり，寸法精度の点で歩留りにも限界がある。
また，超急冷物質の焼鈍法による方法により作製した
Ｒ−Fe−Ｂ薄帯は磁気的に等方性を有するため，焼結磁
石に比べ磁石特性が格段に低く，またこの薄帯を用いて
塑性変形による異方性化をしても，薄帯中の結晶組織が
本質的に等方性であるため焼結磁石と同等の特性は望め
ない。
また，射出成形法及びボンド磁石法の場合，磁性粉末
間の空隙を埋める非磁性バインダーの量が体積構成比で
少なくとも20％以上を必要とするため，特性は他法に比
べ極めて低い。
本発明はこのような問題点を解決し，さらに温度特性
を向上させるもので，その目的は，
（１） 非磁性金属からなる結合相量の低減による特性
向上
（２） 製品寸法精度向上による歩留り改善
（３） R2Fe14B相中のFeの一部をCoで置換することに
よる温度特性の向上
を達成するための製造方法を提供するにある。
［問題点を解決するための手段］
本発明によれば，原子百分率で10〜20％のＲ（但し,R
はＹを含む希土類元素）,5〜15％のＢ（ボロン）,50％
以下のCo（コバルト）及び残部Fe（鉄）よりなる合金粉
末に，体積比で10％以下（零を含まず）のＳ及び非磁性
金属の内から選択された少なくとも一種からなる粉末を
混合し，その混合粉末の成形後,300〜1100℃の温度範囲
で且つ真空又は不活性雰囲気中で熱間加圧成形すること
によって，前記合金からなる磁性相を前記Ｓ及び非磁性
金属の内から選択された少なくとも一種からなるものを
主成分として含む被覆層によって被覆した組織構造を有
することを特徴とする希土類永久磁石の製造方法が得ら
れる。尚,S及び非磁性金属の内の少なくとも一種は,R−
Ｔ−Ｂ系非磁性金属を含む低融点金属であっても良く，
また，粉末あるいは磁性粉末への物理的及び化学的表面
被覆層のいずれであっても良い。また，熱間加圧成形は
いわゆるホットプレス，熱間静水圧プレス，押し出しの
いずれでも可能であるが，製品寸法精度の点から，ホッ
トプレス及び熱間押し出し成形が適している。
すなわち，本発明では，
（１） Ｓ及び非磁性金属の内の少なくとも一種を用い
て，加圧成形することによる緻密化の促進
（２） 磁性粒子を滑らかな界面で包み込むことによる
磁石の「高保磁力化」
（３） 熱間加圧成形を用いることにより，非磁性相の
流動及び磁性相の塑性変形を利用した非磁性相の減少，
及び短時間の緻密化による非磁性金属と磁性相との反応
の抑制の両者に起因するBrの向上
（４） R2Fe14B相中のFeの一部をCoで置換することに
よる温度特性の向上
が得られる。
本発明に適用される永久磁石材料は，一般式
（R1-x-y-zFexCoyBz）1-tMt −（１）
で表わされるが，ここで式中のＲはＹを含む希土類元素
のうち一種又は二種以上が用いられる。また式中のＭは
Zn,Al,S,In,Ga,Sn,Te,Ge,Cu,Pbの一種又は二種以上，あ
るいはこれらの元素と希土類元素,Fe,Bとの非磁性合金
が用いられる。また（１）式において
0.65≦ｘ＋ｙ≦0.85 ０＜ｙ≦0.5 0.05≦ｚ≦0.15
である。FexCoyの量が多すぎるとBrは向上するもののHc
は極端に低下し，少なすぎるとBrの低下により（BH）ｍ
は減少するため,0.65≦ｘ＋ｙ≦0.85とした。またFeの
一部をCoで置換することにより，本系磁石のキュリー点
（Tc）は上昇するがHcはCoの置換量と共に下がる傾向が
ある。また0.5以上の置換ではそのHcの劣化が著しく，
永久磁石材料の特性として，好ましくないため０＜ｙ≦
0.5とする必要がある。
Ｂは磁石特性の向上に著しい効果をもたらすが0.15を
越えると特性の劣化をもたらすため,0.05≦ｚ≦0.15と
した。
また,S又は非磁性金属Ｍは，量が多すぎるとBrの低下
が著しく本発明の目的に合わないため０＜ｔ≦10とす
る。
（１）式で示される磁石材料はR1-x-y-zFexCoyBzなる
組成を有する粉末と,S及び非磁性金属の内の少なくとも
一種からなるものの混合粉末，又は，混合粉末成形体を
300〜1100℃の温度範囲にて真空中又は不活性雰囲気中
で熱間加圧成形することにより製造される。
ここで，熱間加圧成形時の温度を300〜1100℃とした
のは300℃未満では成形体の充分な緻密化が得られず,11
00℃以上ではＲ−Fe−Co−Ｂ磁性微粒子の粒成長及び磁
性相とＳ及び非磁性金属の内の少なくとも一種からなる
ものとの反応が顕著となり良好な磁石特性が得られない
ためである。
＜実施例１＞
純度95％以上のNd,Fe,Co,Bを用いて，アルゴン雰囲気
中で，高周波加熱によりNd13Fe65Co16B6の組成を有する
Nd2（FeCo）14B相を主相とする。インゴットを得た。次
にこのインゴットを相粉砕した後，ボールミルを用いて
平均粒径約４μｍに湿式粉砕した。次に得られた微粉末
を95vol％とし，残部5vol％は，純度99.9％以上のＳ及
び非磁性金属Zn,Al,In,Ga,Ge,Te,Cu,Pb,Sn粉末のうち少
なくとも一種類とし，体積比で95:5の割合で混合しこれ
らの混合粉末をボールミルにて均一分散混合して第１表
に試料No.1〜10として示すような10種類のNd13Fe65Co16
B6と非磁性粉末の混合粉末を得た。これら，粉末を20K
ｅ磁界中にて1.0t/cm2の圧力で成形した。最後にこれ
ら成形体を真空中,6000℃の温度下で,1.0t/cm2の圧力を
加え15分間ホットプレスした。このようにして得られた
磁石の特性を及びV.S.MによりTcを測定した結果を第一
表に示す。試料No.11は比較例として第１表に記載され
たもので,S又は非磁性金属が混合されていないものであ
って，製法は実施例において，非磁性金属と混在しない
ままで，実施例と同様に成形し，ホットプレスしたもの
であり，磁石特性は極めて小さく実用的にはほとんど使
用できない値である。これに対し試料No.1〜10はＳ又は
非磁性金属が混入されていて，しかもホットプレスのた
めに,Nd2（FeCo）14B相の粒成長を極力抑えつつ，焼結
を促進させている。これはiHcを大きくし,Brも改善させ
ていることにより，ひいては（BH）maxを40（MGｅ）
以上とし，非磁性元素をAlとしたものについては48（MG
ｅ）にもなり，これまでの永久磁石では最高級の特性
と言える。
また参考例としてNd15Fe62Co16B7の組成を有する焼結
体の磁気特性及びTcを試料No.12で第１表に記載した。
前述したように，本発明の実施例１による磁石の特性
（BH）maxの向上は，非磁性元素Ｍが磁性相Nd2（FeCo）
14B相に対し低い融点であるために，低温で液相とな
り，磁性相の表面を薄く覆って,S又は非磁性金属である
かもしくはＳ又は非磁性金属を主成分とする合金からな
る被覆層を形成し，しかも加圧高温下であるために，磁
性相と混合した非磁性のＭ元素との反応だけに極力抑え
られて,S及び非磁性金属の内の少なくとも一種を混合し
ないで，また，ホットプレスも行なわず通常の条件で焼
結を行う普通焼結法による磁性相と,R−rich相あるいは
Ｂ−rich相あるいは酸化物相の反応が存在しないか，極
力抑えられるためと考えられる。
尚，参考例として，試料No.12に上記同様の普通焼結
法での組成とデータを記しているが，前述したように普
通焼結法ではNd−rich相,B−rich相の存在をも考慮して
設定しているために，試料１〜10に比較して希土類Ｒを
多めにする必要があるが，本願発明による試料１〜10で
は，磁性相としては化学量論的組成に近いもので良いと
言える。
＜実施例２＞
実施例１で得られたNd12.6Fe63.0Co15.6Ｂ5.8In3（試
料No.3）の一組成を有する成形体をAr中で200〜1200℃
の温度下で1.0t/cm2の圧力を加え,15分間ホットプレス
した。この時の磁石特性を第１図に示す。ホット プレ
ス時温度が,300〜1100℃の間で従来の焼結磁石よりも高
い磁石特性を示している。
第１図に示されるようにホットプレスの温度が400℃
までは，焼結密度ｄの向上に伴って残留磁束密度Brも向
上し,400℃以上ではｄはほぼ7.6（gr/cc）と一定とな
り,Brは900℃までほぼ一定値をとる。
一方,iHcは400℃以下では磁性のNd−Fe−Co−Ｂ相と
非磁性のIn相との反応が不十分であるために小さく，ま
た,900℃以上では反応しすぎのために磁性相が非磁性相
にくわれてしまってしかも粒成長してしまうために，高
い温度になるにつれBrは劣化し,iHcも小さくなってい
る。
このようなことから，（BH）maxも400℃〜900℃のホ
ットプレス温度では大きく，好ましくは500〜700℃の温
度が最大である。
〔効 果〕
以上説明したように，本発明によればR2Fe14B相を主
相する磁性粉末において,Feの一部をCoに置換したR2（F
eCo）14B相を主相とする磁性粉末と,S及び非磁性金属の
内の少なくとも一種からなる粉末を混合した後，熱間加
圧成形を行うことにより温度特性に優れ，従来の焼結法
により製造されるＲ−Ｔ−Ｂ系磁石よりも高い磁気特性
を有する永久磁石を得ることができる。
また，本発明によれば従来の焼結法に比べ低温で成形
体の緻密化が図れ，製品寸法精度向上が実現できる効果
がある。The present invention relates to a rare earth element containing Y (hereinafter abbreviated as R).
And intermetallic compounds of Fe and B, and S and nonmagnetic metal M
The present invention relates to an R 2 T 14 B-M magnet having improved temperature characteristics using an R 2 Fe 14 B-M magnet material comprising the same and a method for producing the same. [Prior Art] Japanese Patent Application Laid-Open No. 59-46008 discloses R / Fe / B permanent magnets.
Bulletin and the 35th meeting of the Japan Society of Applied Magnetics (May 1984
Month). Japanese Patent Application Laid-Open (JP-A) No. 59-64733 is cited as a document of the temperature characteristic improving material. Any of those disclosed in these documents is R 2 T
14 This is a method of obtaining an RTB-based alloy powder having a B phase as a main phase by a normal atmospheric sintering method. In these methods, an alloy having a predetermined composition is melted and pulverized, and the resulting powder is subjected to a magnetic field. After being molded in the mold, it is sintered at a temperature of 900 to 1200 ° C.
To explain in more detail, when producing RTB permanent magnets by the normal pressure sintering method, the densification is performed by a high Nd phase (liquid phase).
Is formed by liquid phase sintering accompanying the appearance of. That is, in the sintered body, there is a liquid phase component phase in addition to the R 2 T 14 B phase which is the magnetic phase and the main phase, and the B-rich phase and the oxide phase which are the non-magnetic phases. There is an Nd-rich phase. Generally, in the present magnet alloy, the magnet properties (especially B
r, (BH) max) greatly changes. In the sintered body obtained by the current process, the volume ratio of these nonmagnetic phases is about 10% or more. Other production methods include a method of annealing a super-quenched substance by a melt spinning method (JP-A-60-100402), an injection molding method and a bond magnet method (JP-A-59-219904). [Problems to be Solved by the Invention] In the case of the normal pressure sintering method, in order to obtain a sufficient densification of the product, the liquid phase component needs to be 5% or more by volume, so There are limits to the magnet properties obtained by sintering. Further, the normal pressure sintering of RTB based magnets is 900-1200.
Since the process is performed at a high temperature of ° C., the yield is limited in terms of dimensional accuracy due to deformation due to the high temperature. In addition, since the R-Fe-B ribbon produced by the method of annealing a super-quenched material has magnetic isotropy, its magnet properties are much lower than that of a sintered magnet. Even if the anisotropy is achieved by plastic deformation, the same properties as a sintered magnet cannot be expected because the crystal structure in the ribbon is essentially isotropic. In addition, in the case of the injection molding method and the bonded magnet method, the amount of the non-magnetic binder that fills the gap between the magnetic powders needs to be at least 20% or more by volume composition ratio, so that the characteristics are extremely low as compared with other methods. The present invention solves such problems and further improves the temperature characteristics. The purpose of the present invention is to (1) improve the characteristics by reducing the amount of a non-magnetic metal bonded phase and (2) improve the yield by improving the product dimensional accuracy. Improvement (3) An object of the present invention is to provide a manufacturing method for achieving an improvement in temperature characteristics by substituting a part of Fe in the R 2 Fe 14 B phase with Co. [Means for Solving the Problems] According to the present invention, R of 10 to 20% in atomic percentage (where R
Is a rare earth element containing Y), 5 to 15% B (boron), 50%
The following alloy powder consisting of Co (cobalt) and the balance Fe (iron) is mixed with a powder consisting of at least one selected from the group consisting of S and non-magnetic metal in a volume ratio of 10% or less (excluding zero). After forming the mixed powder, the magnetic phase composed of the alloy is selected from the S and the non-magnetic metal by hot pressing under a temperature range of 300 to 1100 ° C. and in a vacuum or inert atmosphere. A method for producing a rare-earth permanent magnet, characterized by having a texture structure covered by a coating layer containing at least one of the above-mentioned components as a main component, is obtained. Note that at least one of S and the nonmagnetic metal is R-
It may be a low melting point metal containing a TB nonmagnetic metal,
Also, any of physical and chemical surface coating layers on powder or magnetic powder may be used. Hot pressing can be performed by any of so-called hot pressing, hot isostatic pressing, and extrusion, but from the viewpoint of product dimensional accuracy, hot pressing and hot extrusion are suitable. That is, in the present invention, (1) promotion of densification by pressure molding using at least one of S and a non-magnetic metal (2) "high protection of a magnet by wrapping magnetic particles at a smooth interface (3) By using hot pressing, the non-magnetic phase can be reduced by utilizing the flow of the non-magnetic phase and the plastic deformation of the magnetic phase.
Of Br due to the suppression of the reaction between the non-magnetic metal and the magnetic phase due to the rapid densification and short-time densification (4) Temperature characteristics by replacing part of Fe in the R 2 Fe 14 B phase with Co Is obtained. Permanent magnet material used in the present invention have the general formula (R 1-xyz Fe x Co y B z) 1-t M t - is represented by (1), wherein the rare earth R is containing Y in formula One or more of the elements are used. M in the formula is
One or more of Zn, Al, S, In, Ga, Sn, Te, Ge, Cu, and Pb, or a nonmagnetic alloy of these elements with a rare earth element, Fe, or B is used. In the equation (1), 0.65 ≦ x + y ≦ 0.85 0 <y ≦ 0.5 0.05 ≦ z ≦ 0.15. If the amount of Fe x Co y is too large, Br improves, but Hc
Decreases extremely, and if too small, Br decreases due to the decrease of (BH) m
Is reduced, so that 0.65 ≦ x + y ≦ 0.85. Also, by substituting part of Fe with Co, the Curie point (Tc) of the present magnet increases, but Hc tends to decrease with the amount of Co substitution. In addition, the substitution of 0.5 or more significantly deteriorates Hc,
0 <y ≦
Must be 0.5. B has a remarkable effect on the improvement of the magnet properties, but if it exceeds 0.15, the properties will be degraded, so that 0.05 ≦ z ≦ 0.15. Further, if the amount of S or non-magnetic metal M is too large, the decrease of Br is remarkable and does not meet the purpose of the present invention, so that 0 <t ≦ 10. The magnet material represented by the formula (1) is a mixed powder of a powder having a composition of R 1-xyz Fe x Co y B z and at least one of S and a nonmagnetic metal, or a mixed powder compact.
It is manufactured by hot pressing in a vacuum or in an inert atmosphere in a temperature range of 300 to 1100 ° C. Here, the temperature during hot pressing was set to 300 to 1100 ° C. If the temperature was lower than 300 ° C, sufficient densification of the compact could not be obtained.
If the temperature is higher than 00 ° C., the grain growth of the R—Fe—Co—B magnetic fine particles and the reaction between the magnetic phase and at least one of S and the nonmagnetic metal become remarkable, and good magnet properties cannot be obtained. . <Example 1> Using Nd, Fe, Co, and B having a purity of 95% or more and having a composition of Nd 13 Fe 65 Co 16 B 6 by high frequency heating in an argon atmosphere.
Nd 2 (FeCo) 14 B phase is the main phase. Got an ingot. Next, this ingot was subjected to phase grinding, and then wet-ground to an average particle size of about 4 μm using a ball mill. Next, the obtained fine powder was 95 vol%, and the remaining 5 vol% consisted of at least one of S and nonmagnetic metal Zn, Al, In, Ga, Ge, Te, Cu, Pb, and Sn powder with a purity of 99.9% or more. The powders were mixed at a volume ratio of 95: 5, and these mixed powders were uniformly dispersed and mixed in a ball mill. Ten types of Nd 13 Fe 65 Co 16 shown in Table 1 as Sample Nos. 1 to 10 were prepared.
B 6 and to obtain a mixed powder of non-magnetic powder. 20K of these powders
e Formed at a pressure of 1.0 t / cm 2 in a magnetic field. Finally, these compacts were hot pressed in vacuum at a temperature of 6000 ° C under a pressure of 1.0 t / cm 2 for 15 minutes. Table 1 shows the properties of the magnet thus obtained and the results of measuring Tc by VSM. Sample No. 11 is listed in Table 1 as a comparative example, in which S or a non-magnetic metal was not mixed. It is molded and hot pressed in the same manner as above, and has extremely small magnet properties and is practically unusable. On the other hand, Samples Nos. 1 to 10 contain S or non-magnetic metal and promote sintering while minimizing grain growth of the Nd 2 (FeCo) 14 B phase due to hot pressing. I have. This increases iHc and improves Br, which in turn results in (BH) max of 40 (MGe).
As described above, 48 (MG
e), which can be said to be the highest quality of the permanent magnets so far. As a reference example, the magnetic properties and Tc of a sintered body having a composition of Nd 15 Fe 62 Co 16 B 7 are shown in Table 1 for sample No. 12. As described above, the improvement in the properties (BH) max of the magnet according to the first embodiment of the present invention is based on the fact that the nonmagnetic element M is composed of the magnetic phase Nd 2 (FeCo)
14 Since it has a lower melting point than the B phase, it becomes a liquid phase at a low temperature and covers the surface of the magnetic phase thinly, and is made of S or a nonmagnetic metal or an alloy containing S or a nonmagnetic metal as a main component. Since the layer is formed and the temperature is high under pressure, the reaction is minimized only by the reaction with the non-magnetic M element mixed with the magnetic phase, and at least one of S and the non-magnetic metal is not mixed. It is also considered that there is no reaction between the magnetic phase and the R-rich phase, B-rich phase or oxide phase by the ordinary sintering method in which sintering is performed under normal conditions without performing hot pressing. Can be As a reference example, the composition and data of the same ordinary sintering method as described above are described in sample No. 12. As described above, the presence of the Nd-rich phase and the B-rich phase Therefore, it is necessary to increase the amount of rare earth R in comparison with Samples 1 to 10, but in Samples 1 to 10 according to the present invention, the magnetic phase is close to the stoichiometric composition. Things can be said to be good. <Example 2> The compact having one composition of Nd 12.6 Fe 63.0 Co 15.6 B 5.8 In 3 (sample No. 3) obtained in Example 1 was heated to 200 to 1200 ° C. in Ar.
A pressure of 1.0 t / cm 2 was applied at a temperature of, and hot-pressed for 15 minutes. FIG. 1 shows the magnet characteristics at this time. It shows higher magnet properties than conventional sintered magnets when the temperature during hot pressing is between 300 and 1100 ℃. As shown in Fig. 1, hot press temperature is 400 ℃
Up to 400 ° C., the residual magnetic flux density Br also increases with increasing sintering density d. At 400 ° C. or higher, d becomes almost constant at 7.6 (gr / cc), and Br takes an almost constant value up to 900 ° C. On the other hand, iHc is small at 400 ° C or lower due to insufficient reaction between the magnetic Nd-Fe-Co-B phase and the nonmagnetic In phase, and at 900 ° C or higher due to excessive reaction. However, Br is deteriorated and iHc becomes smaller as the temperature becomes higher, because it is bonded to the nonmagnetic phase and the grains grow. For this reason, (BH) max is also large at the hot pressing temperature of 400 ° C. to 900 ° C., preferably the maximum is 500 ° C. to 700 ° C. [Effects] As described above, according to the present invention, in a magnetic powder having a main phase of R 2 Fe 14 B phase, R 2 (F
eCo) 14 and a magnetic powder B phase as a main phase, after mixing the powder of at least one of S and the non-magnetic metal, excellent temperature characteristics by performing hot pressing, conventional sintering A permanent magnet having higher magnetic properties than an RTB-based magnet manufactured by the method can be obtained. Further, according to the present invention, there is an effect that the compact can be densified at a lower temperature than the conventional sintering method, and the dimensional accuracy of the product can be improved.
【図面の簡単な説明】
第１図はホットプレスによるNd12.6Fe63.0Co15.4Ｂ5.8I
n3のホットプレス温度と磁気特性の関係図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows Nd 12.6 Fe 63.0 Co 15.4 B 5.8 I by hot pressing
n is a relationship diagram of a hot-press temperature and magnetic properties of 3.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 佐々木 欣也 仙台市郡山６丁目７番１号 東北金属工 業株式会社内 (72)発明者 藤原 照彦 仙台市郡山６丁目７番１号 東北金属工 業株式会社内 (56)参考文献 特開 昭58−182802（ＪＰ，Ａ) 特開 昭61−48904（ＪＰ，Ａ) 特開 昭59−204212（ＪＰ，Ａ) 特開 昭59−219453（ＪＰ，Ａ) 特開 昭60−52556（ＪＰ，Ａ) ────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kinya Sasaki 6-7-1, Koriyama, Sendai Tohoku Metal Works Industry Co., Ltd. (72) Inventor Teruhiko Fujiwara 6-7-1, Koriyama, Sendai Tohoku Metal Works Industry Co., Ltd. (56) References JP-A-58-182802 (JP, A) JP-A-61-48904 (JP, A) JP-A-59-204212 (JP, A) JP-A-59-219453 (JP, A) JP-A-60-52556 (JP, A)
Claims (1)
類元素）,5〜15％のＢ（ボロン）,50％以下のCo（コバ
ルト）及び残部Fe（鉄）よりなる合金粉末に，体積比で
10％以下（零を含まず）のＳ及び非磁性金属の内から選
択された少なくとも一種からなる粉末を混合し，その混
合粉末の成形後,300〜1100℃の温度範囲で且つ真空又は
不活性雰囲気中で熱間加圧成形することによって，前記
合金からなる磁性相を前記Ｓ及び非磁性金属の内から選
択された少なくとも一種からなるものを主成分として含
む被覆層によって被覆した組織構造を有することを特徴
とする希土類永久磁石の製造方法。(57) [Claims] An alloy powder consisting of 10 to 20% of atomic percent R (where R is a rare earth element containing Y), 5 to 15% of B (boron), 50% or less of Co (cobalt) and the balance Fe (iron) , By volume ratio
10% or less (excluding zero) of S and a powder of at least one selected from non-magnetic metals are mixed, and after forming the mixed powder, in a temperature range of 300 to 1100 ° C and in a vacuum or inert It has a structure structure in which a magnetic phase made of the alloy is covered with a coating layer containing, as a main component, at least one selected from the group consisting of S and a non-magnetic metal by hot pressing in an atmosphere. A method for producing a rare earth permanent magnet, comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61111827A JP2779794B2 (en) | 1986-05-17 | 1986-05-17 | Manufacturing method of rare earth permanent magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61111827A JP2779794B2 (en) | 1986-05-17 | 1986-05-17 | Manufacturing method of rare earth permanent magnet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62270746A JPS62270746A (en) | 1987-11-25 |
| JP2779794B2 true JP2779794B2 (en) | 1998-07-23 |
Family
ID=14571156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61111827A Expired - Lifetime JP2779794B2 (en) | 1986-05-17 | 1986-05-17 | Manufacturing method of rare earth permanent magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2779794B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103248314A (en) * | 2012-02-09 | 2013-08-14 | 株式会社牧田 | Electric power tool |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2794704B2 (en) * | 1987-12-29 | 1998-09-10 | 大同特殊鋼株式会社 | Manufacturing method of anisotropic permanent magnet |
| JPH0252413A (en) * | 1988-08-16 | 1990-02-22 | Sanyo Special Steel Co Ltd | Manufacture of permanent magnet |
| JP2739329B2 (en) * | 1988-10-20 | 1998-04-15 | 株式会社トーキン | Method for producing alloy powder for polymer composite type rare earth magnet |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS58182802A (en) * | 1982-04-21 | 1983-10-25 | Pioneer Electronic Corp | Preparation of permanent magnet |
| JPS59204212A (en) * | 1983-05-06 | 1984-11-19 | Sumitomo Special Metals Co Ltd | Isotropic permanent magnet and manufacture thereof |
| JPS59219453A (en) * | 1983-05-24 | 1984-12-10 | Sumitomo Special Metals Co Ltd | Permanent magnet material and its production |
| JPS6052556A (en) * | 1983-09-02 | 1985-03-25 | Sumitomo Special Metals Co Ltd | Permanent magnet and its production |
| JPS6148904A (en) * | 1984-08-16 | 1986-03-10 | Hitachi Metals Ltd | Manufacture of permanent magnet |
-
1986
- 1986-05-17 JP JP61111827A patent/JP2779794B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103248314A (en) * | 2012-02-09 | 2013-08-14 | 株式会社牧田 | Electric power tool |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62270746A (en) | 1987-11-25 |
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