JPH05234732A - Rare earth element bonded magnet - Google Patents
Rare earth element bonded magnetInfo
- Publication number
- JPH05234732A JPH05234732A JP4036613A JP3661392A JPH05234732A JP H05234732 A JPH05234732 A JP H05234732A JP 4036613 A JP4036613 A JP 4036613A JP 3661392 A JP3661392 A JP 3661392A JP H05234732 A JPH05234732 A JP H05234732A
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- rare earth
- bonded magnet
- earth element
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、希土類金属と遷移金属
群からなる希土類ボンド磁石に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rare earth bonded magnet composed of a rare earth metal and a transition metal group.
【０００２】[0002]
【従来の技術】従来、主にＳｍとＣｏからなるＲ2ＴＭ
17系希土類ボンド磁石に関しては、特公平１−２２６９
６号公報，特公平１−２５８１９号公報，特公平１−４
０４８３号公報やその引用特許公報や論文などに多く報
告されているように、ＳｍとＣｏの二元系ではなく、Ｆ
ｅ，Ｃｕ，Ｚｒなどを含んだ五元系以上の組成系となっ
ている。さらに、ＲとしてＳｍ単独ではなく他のＲで置
換させる組成系についても、特開昭６０−２１８４４５
号公報など特許公報や論文などに報告されている。 ま
た、Ｒ2Ｆｅ17Ｎx系希土類ボンド磁石に関しては、例え
ば特開平２−５７６０３号公報，特開平２−５７６６３
号公報など特許公報およびＪ．Ｍａｇｎ．Ｍａｇｎ．Ｍ
ａｔｅｒ．，８７（１９９０）Ｌ２５１をはじめとする
論文などに、Ｓｍ2Ｆｅ17Ｎx系などとして報告されてい
る。2. Description of the Related Art Conventionally, R 2 TM mainly composed of Sm and Co
Regarding the 17 series rare earth bonded magnet, Japanese Patent Publication No. 1-2269
No. 6, Japanese Patent Publication No. 1-25819, No. Japanese Patent Publication 1-4
As reported in many publications such as the 0483 publication, its cited patent publications, papers, etc., it is not a binary system of Sm and Co, but F
The composition system is a quinary or higher composition system including e, Cu, Zr and the like. Further, as to a composition system in which Sm is not the sole R but is substituted with another R, JP-A-60-218445 is also used.
It is reported in patent gazettes such as issue gazettes and papers. Regarding the R 2 Fe 17 N x rare earth bonded magnet, for example, JP-A-2-57603 and JP-A-2-57663.
Patent gazettes such as Gazette and J. Magn. Magn. M
ater. , 87 (1990) L251 and the like, and Sm 2 Fe 17 N x system is reported.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、従来の
技術におけるボンド磁石においては、以下の問題点を有
する。However, the conventional bonded magnet has the following problems.
【０００４】（１）Ｒ2ＴＭ17系の場合、飽和磁化がＳ
ｍ2Ｃｏ17では１２ｋＧとＮｄ2Ｆｅ14Ｂの１６ｋＧやＳ
ｍ2Ｆｅ17Ｎxの１５.４ｋＧと比較すると低く、ポンド
磁石の磁気特性も低い。(1) In the case of R 2 TM 17 system, the saturation magnetization is S
m 2 Co 17 has 12 kG and Nd 2 Fe 14 B has 16 kG and S.
It is low as compared with 15.4 kG of m 2 Fe 17 N x , and the magnetic properties of the pound magnet are also low.
【０００５】（２）Ｓｍ2Ｆｅ17Ｎxの場合、例えば平均
粒径で２〜３μｍと５μｍ以下の微粉末にしないと十分
に高い磁気特性が得られないが、このような粉末を用い
て得られるボンド磁石の成形密度は低く、ボンド磁石と
しては十分に高い磁気特性が得られない。(2) In the case of Sm 2 Fe 17 N x , sufficiently high magnetic characteristics cannot be obtained unless fine powder having an average particle diameter of 2 to 3 μm and 5 μm or less is used. The obtained bonded magnet has a low molding density and cannot have sufficiently high magnetic properties as a bonded magnet.
【０００６】（３）Ｓｍ2Ｆｅ17Ｎxの場合、Ｓｍを安価
な他の軽希土類金属で置換すると磁気特性が大幅に低下
することから、低コスト化が困難である。(3) In the case of Sm 2 Fe 17 N x , if Sm is replaced with another inexpensive light rare earth metal, the magnetic properties will be significantly deteriorated, and it is difficult to reduce the cost.
【０００７】（４）Ｓｍ2Ｆｅ17Ｎxの場合、キューリー
温度が４７２℃とＳｍ2Ｃｏ17系の９１７℃と比較する
と低く、鉄を多く含んでいることから赤錆の発生などに
より耐食性にも劣るなど信頼性に劣る。(4) In the case of Sm 2 Fe 17 N x , the Curie temperature is 472 ° C., which is lower than 917 ° C. of the Sm 2 Co 17 system, and since it contains a large amount of iron, it also has corrosion resistance due to the occurrence of red rust. Inferior, such as inferior.
【０００８】そこで、本発明はこのような問題点を解決
するもので、その目的とするところは、従来よりも高い
磁気特性を有し、低コストでかつ信頼性も高く、製造方
法も容易である希土類ボンド磁石を提供することにあ
る。Therefore, the present invention solves such a problem, and an object of the present invention is to have magnetic properties higher than those of the conventional ones, low cost and high reliability, and easy manufacturing method. It is to provide a certain rare earth bonded magnet.
【０００９】[0009]
【課題を解決するための手段】本発明の希土類ボンド磁
石は、基本組成が主にＲおよびＣｏからなり必要に応じ
てＦｅ，Ｃｕ，Ｚｒなどを含むいわゆるＲ2ＴＭ17系の
粉末と、主にＲ，ＦｅおよびＮからなるいわゆるＲ2Ｆ
ｅ17Ｎx系の粉末を混合させたことを特徴とする希土類
ボンド磁石。The rare earth bonded magnet of the present invention comprises a so-called R 2 TM 17 series powder whose basic composition is mainly R and Co and, if necessary, Fe, Cu, Zr, etc. Is a so-called R 2 F composed of R, Fe and N
A rare earth bonded magnet, characterized in that a powder of e 17 N x system is mixed.
【００１０】[0010]
【作用】本発明の上記の構成によれば、Ｒ2ＴＭ17系粉
末とＲ2Ｆｅ17Ｎx系粉末を混合し、ボンド磁石とするこ
とにより、以下の効果を有する。According to the above-mentioned constitution of the present invention, the following effects are obtained by mixing the R 2 TM 17 system powder and the R 2 Fe 17 N x system powder to form a bond magnet.
【００１１】（１）平均粒径２〜３μｍのＲ2Ｆｅ17Ｎx
系粉末と平均粒径１０〜３０μｍのＲ2ＴＭ17系粉末を
混合することにより、いわゆる二山分布効果（例えば大
豆１００ｃｃと米１００ｃｃを混合すると２００ｃｃよ
りかなり減少する効果）によりボンド磁石の成形密度を
高めることができ、磁気特性を向上させることができ
る。（２）Ｒ2ＴＭ17系ボンド磁石用合金は、Ｒとして
Ｓｍ以外の安価な軽希土類金属による置換が可能であ
り、軽希土類置換型Ｒ2ＴＭ17系粉末とＲ2Ｆｅ17Ｎx系
粉末を混合させることにより、Ｓｍの使用量を減じるこ
とができ、低コスト化が可能となる。(1) R 2 Fe 17 N x having an average particle size of 2 to 3 μm
By mixing the R 2 TM 17 system powder system powder and the average particle size 10 to 30 [mu] m, the molding density of the bonded magnet by so-called two-peak distribution effects (such as soybean 100cc and rice 100cc considerably reduced than 200cc when mixing to effect) Can be improved, and the magnetic characteristics can be improved. (2) The R 2 TM 17- based bonded magnet alloy can be replaced by an inexpensive light rare earth metal other than Sm as R, and the light rare earth-substitution type R 2 TM 17 based powder and R 2 Fe 17 N x based powder can be used. By mixing S, the amount of Sm used can be reduced and the cost can be reduced.
【００１２】（３）Ｒ2Ｆｅ17Ｎx系は比較的保磁力の得
られにくいが、高保磁力のＲ2ＴＭ17系と混合すること
により、最終的なボンド磁石の保磁力・角形性は実用上
十分高い値となり、エネルギー積など磁気特性の向上の
みならず信頼性の向上という効果も有する。(3) The R 2 Fe 17 N x system is relatively hard to obtain a coercive force, but when mixed with the R 2 TM 17 system having a high coercive force, the coercive force / squareness of the final bonded magnet is improved. The value is sufficiently high for practical use, and not only magnetic properties such as energy product are improved but also reliability is improved.
【００１３】[0013]
【実施例】以下、本発明について、実施例に基づいて詳
細に説明する。EXAMPLES The present invention will be described in detail below based on examples.
【００１４】（実施例１）Ｓｍ＝２４.２，Ｃｏ＝４５.
７，Ｆｅ＝２２.９，Ｃｕ＝５.３，Ｚｒ＝１.９重量％
の組成となるように、高周波溶解炉を用いアルゴンガス
雰囲気中で溶解・鋳造しインゴットを作成した。このイ
ンゴットにアルゴンガス雰囲気中で、１１６０℃で２４
時間の溶体化処理を、８００℃で８時間保持した後０.
５℃／分で４００℃まで連続冷却させる時効処理を施し
た。その後、スタンプミルで粗粉砕、ボールミルで微粉
砕し、平均粒径で１７μｍの粉末を得た。このＲ2ＴＭ
17系粉末をＡ１とする。(Embodiment 1) Sm = 24.2, Co = 45.
7, Fe = 22.9, Cu = 5.3, Zr = 1.9% by weight
The ingot was prepared by melting and casting in a high-frequency melting furnace in an argon gas atmosphere so as to obtain the above composition. This ingot is placed in an argon gas atmosphere at 1160 ° C. for 24 hours.
After the solution heat treatment for 8 hours was held at 800 ° C. for 8 hours,
An aging treatment for continuously cooling to 5 ° C / min to 400 ° C was performed. Then, it was roughly pulverized with a stamp mill and finely pulverized with a ball mill to obtain a powder having an average particle size of 17 μm. This R 2 TM
The 17 series powder is designated as A1.
【００１５】Ｓｍ＝２４.５，Ｆｅ＝７５.５重量％の組
成となるように、高周波溶解炉を用いアルゴンガス雰囲
気中で溶解・鋳造しインゴットを作成した。このインゴ
ットにアルゴンガス雰囲気中で１２８０℃で３時間の均
質化処理を施した後、２０〜１００μｍに粗粉砕した。
この粉末を水素＋アンモニア混合ガス中で４５０℃で１
時間、アルゴンガス中で４５０℃で２時間の窒化処理を
施した。その後、プラネタリーミルで微粉砕し、平均粒
径で２.６μｍの粉末を得た。このＲ2Ｆｅ17Ｎx系粉末
をＢ１とする。An ingot was prepared by melting and casting in a argon gas atmosphere using a high frequency melting furnace so that the composition was Sm = 24.5, Fe = 75.5% by weight. This ingot was homogenized at 1280 ° C. for 3 hours in an argon gas atmosphere, and then roughly crushed to 20 to 100 μm.
This powder was mixed with hydrogen + ammonia at 450 ° C for 1 hour.
The nitriding treatment was performed for 2 hours at 450 ° C. in argon gas. Then, it was finely pulverized with a planetary mill to obtain a powder having an average particle size of 2.6 μm. This R 2 Fe 17 N x powder is designated as B1.
【００１６】上記二種類の粉末を（１００−ａ）Ａ１＋
（ａ）Ｂ１となるように混合した。ここでａは重量％で
０，１０，３０，５０，６０，７０，８０，１００であ
る。得られた粉末にエポキシ系樹脂３重量％を混合・混
練し、１５ｋＯｅの磁場中において７０ｋｇ／ｍｍ2の
成形圧で圧縮成形し、１５０℃で１時間のキュアーを施
しボンド磁石とした。The above-mentioned two kinds of powders are (100-a) A1 +
(A) It was mixed so as to become B1. Here, a is 0, 10, 30, 50, 60, 70, 80, 100 in weight percent. The obtained powder was mixed and kneaded with 3% by weight of an epoxy resin, compression-molded at a molding pressure of 70 kg / mm 2 in a magnetic field of 15 kOe, and cured at 150 ° C. for 1 hour to obtain a bonded magnet.
【００１７】得られたボンド磁石の磁気特性を以下に示
す。The magnetic properties of the obtained bonded magnet are shown below.
【００１８】 以上から分かるように、二種類の粉末を単独で使用した
ときと比較すると、混合して使用することにより高い磁
気特性が得られている。このことは、粉末の二山分布効
果によりボンド磁石の成形密度が向上しそれに伴なって
磁化も向上したことに加えて、Ｒ2Ｆｅ17Ｎx系粉末単独
と比較すると、保磁力や角形性の向上により高いエネル
ギー積が得られている。特にＲ2Ｆｅ17Ｎx系粉末（Ｂ
１）が６０％前後で高い磁気特性が得られているが、上
記の改善効果のバランスが最高になったからと考えられ
る。しかし、本発明の効果はその領域に限定されるもの
ではない。[0018] As can be seen from the above, as compared with the case where the two kinds of powders are used alone, the high magnetic characteristics are obtained by using the mixture in a mixed manner. This means that the compact density of the bonded magnet was improved due to the double peak distribution effect of the powder, and the magnetization was also improved accordingly, and in addition to the coercive force and the squareness of the R 2 Fe 17 N x powder alone. A higher energy product is obtained by improving In particular, R 2 Fe 17 N x powder (B
In 1), high magnetic characteristics were obtained at around 60%, but it is considered that the balance of the above-mentioned improvement effects was maximized. However, the effect of the present invention is not limited to that area.
【００１９】（実施例２）Ｓｍ＝６.７，Ｃｅ＝２.３，
Ｐｒ＝６.８，Ｎｄ＝６.９，Ｃｏ＝５１.２，Ｆｅ＝１
５.９，Ｃｕ＝６.８，Ｚｒ＝３.４重量％の組成となる
ように、実施例１と同様の方法を用い、Ｒ2ＴＭ17系粉
末Ａ２とした。ここで、溶体化処理条件は１１６０℃×
８時間，時効条件は７８０℃×８時間，得られた粉末の
平均粒径は２１μｍだった。(Embodiment 2) Sm = 6.7, Ce = 2.3,
Pr = 6.8, Nd = 6.9, Co = 51.2, Fe = 1
Using the same method as in Example 1, R 2 TM 17 based powder A2 was obtained so that the composition would be 5.9, Cu = 6.8, and Zr = 3.4 wt%. Here, the solution treatment condition is 1160 ° C. ×
The aging condition was 8 hours, the temperature was 780 ° C. × 8 hours, and the average particle size of the obtained powder was 21 μm.
【００２０】Ｓｍ＝２２.５，Ｎｄ＝２.３，Ｆｅ＝７
０.１，Ｃｏ＝５.１重量％の組成となるように窒化前の
インゴットを作成し、実施例１と同様の方法を用い、Ｒ
2Ｆｅ17Ｎx系粉末Ｂ２とした。ここで、均質化処理条件
は１１５０℃×２４時間，窒化条件は５００℃×４時
間，得られた粉末の平均粒径は２.４μｍだった。Sm = 22.5, Nd = 2.3, Fe = 7
An ingot before nitriding was prepared so as to have a composition of 0.1 and Co = 5.1% by weight, and R was used in the same manner as in Example 1.
2 Fe 17 N x powder B2 was used. Here, the homogenizing condition was 1150 ° C. × 24 hours, the nitriding condition was 500 ° C. × 4 hours, and the average particle size of the obtained powder was 2.4 μm.
【００２１】Ａ２とＢ２とを４：６（重量比）で混合
し、実施例１と同様にボンド磁石を作成した。磁気特性
を以下に示す。A2 and B2 were mixed at a ratio of 4: 6 (weight ratio) to prepare a bonded magnet in the same manner as in Example 1. The magnetic characteristics are shown below.
【００２２】 Ｂｒ＝ ９.４ｋＧ ｉＨｃ＝１０.８ｋＯｅ （ＢＨ）max＝１７.２ＭＧＯｅ このボンド磁石は、Ｓｍの量が１６％と少ないにもかか
わらず、非常に高い磁気特性を示している。Br = 9.4 kG iHc = 10.8 kOe (BH) max = 17.2 MGOe This bonded magnet shows very high magnetic characteristics despite the small amount of Sm of 16%.
【００２３】（実施例３）先ず、実施例１のＡ１とＢ１
を重量比で４：６で混合しボンド磁石としたものを本発
明とする。また、Ｂ１のみでボンド磁石としたものを比
較例とした。(Embodiment 3) First, A1 and B1 of Embodiment 1
The present invention is a bonded magnet obtained by mixing the above in a weight ratio of 4: 6. In addition, a comparative example was one in which only B1 was used as a bonded magnet.
【００２４】直径１０ｍｍ，高さ７ｍｍの円柱状とし、
１５０℃×１０００時間の経時変化試験を行なったが、
本発明が−４.９％の減磁に対し、比較例は−３２.９％
と大きな減磁が生じた。A cylindrical shape having a diameter of 10 mm and a height of 7 mm,
A aging test was conducted at 150 ° C for 1000 hours.
The present invention has a demagnetization of -4.9%, whereas the comparative example has a demagnetization of -32.9%.
And a big demagnetization occurred.
【００２５】（実施例４）実施例３の本発明と比較例を
用い、試料形状を外径３０ｍｍ，内径２０ｍｍ，高さ８
ｍｍのリング状磁石を作成し、８０℃×９５％ＲＨ×１
０００時間の耐湿試験にかけた。(Example 4) Using the present invention of Example 3 and a comparative example, the sample shape was 30 mm in outer diameter, 20 mm in inner diameter, and 8 in height.
Make a ring-shaped magnet of 80mm, 80 ℃ × 95% RH × 1
It was subjected to a humidity resistance test for 000 hours.
【００２６】比較例が鉄の酸化物と思われる赤褐色の物
体が観察されたのに対し、本発明は何ら変化は生じなか
った。In the comparative example, a reddish-brown body, which is thought to be an oxide of iron, was observed, whereas no change occurred in the present invention.
【００２７】また、リング状試料の強度は、試験後、本
発明が７２ｋｇ（１０個の平均）であったのに対し、比
較例では全て２１ｋｇであった。After the test, the strength of the ring-shaped sample was 72 kg (average of 10 pieces) in the present invention, whereas it was 21 kg in all the comparative examples.
【００２８】[0028]
【発明の効果】以上述べたように本発明によれば、Ｒ2
ＴＭ17系粉末とＲ2Ｆｅ17Ｎx系粉末を混合しボンド磁石
とすることを特徴とすることにより、磁気特性の高い希
土類ボンド磁石を低コストでかつ簡便に作成することが
できることから、応用するモータやデバイスのさらなる
高性能化，小型化を実現できるなど応用面にも多大の効
果を有するものである。As described above, according to the present invention, R 2
The rare earth bonded magnet having high magnetic properties can be easily manufactured at low cost by using a mixture of TM 17 powder and R 2 Fe 17 N x powder to form a bonded magnet. It also has a great effect on the application side, such as achieving higher performance and downsizing of motors and devices.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 下田 達也 長野県諏訪市大和３丁目３番５号 セイコ ーエプソン株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuya Shimoda 3-3-5 Yamato, Suwa-shi, Nagano Seiko Epson Corporation
Claims (1)
土類元素のうち１種または２種以上：以下Ｒと略す）お
よびＣｏからなり必要に応じてＦｅ，Ｃｕ，Ｚｒなどを
含むいわゆるＲ2ＴＭ17系（ＴＭ：遷移金属群）の粉末
と、主にＲ，ＦｅおよびＮからなるいわゆるＲ2Ｆｅ17
Ｎx系の粉末を混合させたことを特徴とする希土類ボン
ド磁石。1. A so-called R, whose basic composition is mainly composed of a rare earth metal (one or more kinds of rare earth elements including Y: hereinafter abbreviated as R) and Co and optionally contains Fe, Cu, Zr and the like. 2 TM 17 series (TM: transition metal group) powder and so-called R 2 Fe 17 mainly composed of R, Fe and N
A rare earth bonded magnet, characterized in that N x powder is mixed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4036613A JPH05234732A (en) | 1992-02-24 | 1992-02-24 | Rare earth element bonded magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4036613A JPH05234732A (en) | 1992-02-24 | 1992-02-24 | Rare earth element bonded magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05234732A true JPH05234732A (en) | 1993-09-10 |
Family
ID=12474656
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4036613A Pending JPH05234732A (en) | 1992-02-24 | 1992-02-24 | Rare earth element bonded magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05234732A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5647886A (en) * | 1993-11-11 | 1997-07-15 | Seiko Epson Corporation | Magnetic powder, permanent magnet produced therefrom and process for producing them |
| US6139765A (en) * | 1993-11-11 | 2000-10-31 | Seiko Epson Corporation | Magnetic powder, permanent magnet produced therefrom and process for producing them |
-
1992
- 1992-02-24 JP JP4036613A patent/JPH05234732A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5647886A (en) * | 1993-11-11 | 1997-07-15 | Seiko Epson Corporation | Magnetic powder, permanent magnet produced therefrom and process for producing them |
| US6139765A (en) * | 1993-11-11 | 2000-10-31 | Seiko Epson Corporation | Magnetic powder, permanent magnet produced therefrom and process for producing them |
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