JPS61119009A - Manufacture of rare-earth cobalt magnet - Google Patents
Manufacture of rare-earth cobalt magnetInfo
- Publication number
- JPS61119009A JPS61119009A JP59241057A JP24105784A JPS61119009A JP S61119009 A JPS61119009 A JP S61119009A JP 59241057 A JP59241057 A JP 59241057A JP 24105784 A JP24105784 A JP 24105784A JP S61119009 A JPS61119009 A JP S61119009A
- Authority
- JP
- Japan
- Prior art keywords
- sintering
- rare earth
- container
- oxide
- earth cobalt
- 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.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/026—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets protecting methods against environmental influences, e.g. oxygen, by surface treatment
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は希土類コバルト磁石の製造方法に関するもので
特に焼結体の焼結容器との焼付反応を防止し、高密度で
かつ高磁気特性を有する希土類コバルト磁石を得る焼結
方法に関するものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a rare earth cobalt magnet, and in particular, a method for manufacturing a rare earth cobalt magnet, which prevents a seizure reaction between a sintered body and a sintered container, and has high density and high magnetic properties. The present invention relates to a sintering method for obtaining a rare earth cobalt magnet.
希土類コバルト金属間化合物は希土類金属の含有量によ
り種々のＣｏＲ相（以下ＲはＳｍ、Ｐｒ、Ｃｅ等の希土
類金属を表わす）を形成することはよく知られているが
、現在実用化されているのはＲＣｏ。It is well known that rare earth cobalt intermetallic compounds form various CoR phases (hereinafter R represents rare earth metals such as Sm, Pr, Ce, etc.) depending on the content of rare earth metals, but this is not currently in practical use. The one is RCo.
系およびＲ，Ｃｏ、、系の希土類コバルト磁石である。and R, Co, rare earth cobalt magnets.
ＲＣＯ，系永久磁石（例えば特公昭４８−３６４号、特
開昭４６−６５０３〜６５０５号の各公報参照）は、最
初に実用化され、保磁力（ｒＨｃ ）が高い（一般に１
０ＫＯｅ以上）という利点を有する。RCO, type permanent magnets (see, for example, Japanese Patent Publications No. 48-364 and Japanese Patent Application Laid-open Nos. 46-6503 to 6505) were the first to be put to practical use and had a high coercive force (rHc) (generally 1
0 KOe or more).
一方、馬ｃＯｔｙ系永久磁石（例えば特開昭５０−１１
１５９９号、同５２−１１５０００号、同５６−１５６
７５４号、同５７−１２Ｅ１９０５号、特公昭５５−５
０１００号の各公報参照）は、最大エネルギー積が高い
（一般に２２ＭＧ・００以上）という利点を有する。On the other hand, horse cOty type permanent magnets (for example,
No. 1599, No. 52-115000, No. 56-156
No. 754, No. 57-12E1905, Special Publication No. 55-5
0100) has the advantage of having a high maximum energy product (generally 22MG·00 or more).
上述した希土類コバルト磁石の製造工程は、一般に次の
とうりである。まず各原料を所定の成分となるように調
整し、これらを溶解して得られたインゴットを、所定の
粒径に粉砕する。この原料粉末あるいは還元拡散法によ
り準備した原料粉末を磁場中でプレス成形して成形体を
得る。この成形体を真空（１０″′２〜１０″″６ Ｔ
ｏｒｒ程度）、水素ガスまたは不活性ガス雰囲気中で焼
結して焼結体を得る。The manufacturing process of the rare earth cobalt magnet described above is generally as follows. First, each raw material is adjusted to have a predetermined composition, and an ingot obtained by melting these is pulverized to a predetermined particle size. This raw material powder or the raw material powder prepared by the reduction diffusion method is press-molded in a magnetic field to obtain a compact. This molded body is heated under vacuum (10''2 to 10''6 T
orr) in a hydrogen gas or inert gas atmosphere to obtain a sintered body.
そして、得られた焼結体に熱処理を施して永久磁石合金
を得る。Then, the obtained sintered body is heat treated to obtain a permanent magnet alloy.
上記の焼結工程において、成形体はステンレス鋼等の耐
熱鋼またはモリブデン、タングステン製等の材料からな
る焼結容器内に装填される。この場合、焼結容器内に直
接成形体を装填して且的とする焼結温度で焼結すると焼
結体と焼結容器との間に焼付反応が生じる。この現象を
防止するため、通常は焼結温度を目的とした温度より０
．５〜１０％だけ低（して焼結を行なっている。従って
得られた焼結体の密度が低下し、残留磁束密度（Ｂｒ）
も目標とする値の９５〜９８％しか得られないという問
題がある。In the above-mentioned sintering process, the molded body is loaded into a sintering container made of heat-resistant steel such as stainless steel or a material such as molybdenum or tungsten. In this case, when the molded body is directly loaded into the sintering container and sintered at a target sintering temperature, a sintering reaction occurs between the sintered body and the sintering container. To prevent this phenomenon, the sintering temperature is usually set to 0.
．． Sintering is carried out by reducing the residual magnetic flux density (Br) by 5 to 10%.
However, there is a problem in that only 95 to 98% of the target value can be obtained.
本発明は、上記従来焼結方法を鑑み、希土類コバルト磁
石の製造に際して、焼結時に焼結体と焼結容器との焼付
反応を防止し、目的の焼結温度での焼結処理を可能とし
、高密度、高磁気特性を有する希土類コバルト磁石を得
ることができる焼結方法を提供することを且的とする。In view of the above-mentioned conventional sintering method, the present invention prevents the sintering reaction between the sintered body and the sintering container during sintering and enables the sintering process at the desired sintering temperature when manufacturing rare earth cobalt magnets. It is also an object of the present invention to provide a sintering method capable of obtaining rare earth cobalt magnets with high density and high magnetic properties.
本発明の希土類コバルト磁石の製造方法は、希土類コバ
ルト合金粉末をプレス成形して得られた成形体を焼結容
器内に装填し、この容器を焼結炉内に保持して焼結する
場合に該焼結容器内表面を希土類酸化物（Ｙｔ Ｏｓも
含む）またはＭｇＯ，ＣａＯ等の酸化物で塗布、溶射お
よび蒸着等の手法により被覆せしめ、その焼結容器内に
上記成形体を装填して、焼結処理することにより焼結体
と焼結容器間の焼付反応を防止するものである。以下本
発明について詳細に説明する。The method for producing a rare earth cobalt magnet of the present invention involves loading a compact obtained by press-molding rare earth cobalt alloy powder into a sintering container, and holding the container in a sintering furnace for sintering. The inner surface of the sintered container is coated with a rare earth oxide (including YtOs) or an oxide such as MgO, CaO, etc. by coating, thermal spraying, vapor deposition, etc., and the molded body is loaded into the sintered container. The sintering process prevents a seizure reaction between the sintered body and the sintered container. The present invention will be explained in detail below.
従来方法では、焼結進行時に焼結体から希土類蒸気が発
生し、焼結容器の焼結体との接触面を活性化させるため
に両者間に焼付反応が生じることがわかった。本発明者
等はその防止策を種々検討した結果、上記容器の少なく
とも焼結体（容器内への装填時は成形体）と接触する部
分を焼結時に発生する希土類蒸気に還元されずかつ、焼
結の進行を阻害しない物質で防止すれば良いことを見出
した。第１図に希土類および主だった酸化物生成標準エ
ネルギーと温度の関係を示したものである。It has been found that in the conventional method, rare earth vapor is generated from the sintered body during sintering, and a sintering reaction occurs between the two to activate the contact surface of the sintering container with the sintered body. As a result of studying various preventive measures, the present inventors have found that at least the portion of the container that comes into contact with the sintered body (the molded body when loaded into the container) is not reduced to the rare earth vapor generated during sintering, and It has been found that this can be prevented by using a substance that does not inhibit the progress of sintering. Figure 1 shows the relationship between standard energy of rare earth and major oxide formation and temperature.
第１図よりエネルギーが低いほど酸化しやすく還元しに
くいことがわかる。すなわち第１図は、その物質が酸化
した場合還元されず安定であることを示している。よっ
て、第１図より成形体に含有される希土類元素と同一ま
たは該希土類元素よりもエネルギーの低い希土類元素の
酸化物（ＹｔＯ。From Figure 1, it can be seen that the lower the energy, the easier it is to oxidize and the harder it is to reduce. That is, FIG. 1 shows that when the substance is oxidized, it is not reduced and is stable. Therefore, from FIG. 1, an oxide of a rare earth element (YtO) having the same or lower energy than the rare earth element contained in the molded body.
含む）またはＭｇＯ、ＣａＯにて焼結容器の内面を被覆
することにより、焼結容器は焼結処理時に焼結体より発
生する希土類蒸気に還元されず焼結体との焼付反応を防
止できる。ここで、焼結容器への上記酸化物の被覆は塗
布、溶射、蒸着方法等の公知等で行なうことができる。By coating the inner surface of the sintered container with MgO or CaO, the sintered container is not reduced to rare earth vapor generated from the sintered body during the sintering process, and a seizure reaction with the sintered body can be prevented. Here, the sintering container can be coated with the above-mentioned oxide by a known method such as coating, thermal spraying, or vapor deposition.
実施例１
ａｍ （Ｃｏｂａｌ Ｆｅｏ、２０ Ｃｕｏ、＋ ｚｒ
Ｏ，ｏ＋２） ７．０１７）組成を有するブロック状成
形体（重さ１ｏｏｇ）１を、第２Ｍに云す上へかモリブ
デン朧の溶結容器２内に装填した。この容器２は、その
内面上酸化サマリウム（Ｓｍｔ Ｏ３）粉末３を塗布し
たものである。成形体１を装填した後、モリブデン製の
焼結７タ４を載置した。この焼結容器を焼結炉に入れ、
真空中（１０−２〜１０− Ｔｏｒｒ ）で１２００℃
×油の条件にて焼結処理を行なった。このようにして得
られた焼結体は焼付反応は皆無であった。ｔＸ１表に最
適熱処理後の磁気特性を示す。Example 1 am (Cobal Feo, 20 Cuo, + zr
A block-shaped molded body (weight 10og) 1 having the composition 7.017) was loaded into a molybdenum haze welding container 2 as described in No. 2M. This container 2 has samarium oxide (Smt O3) powder 3 coated on its inner surface. After loading the compact 1, a molybdenum sintered 7-piece 4 was placed. Put this sintering container into a sintering furnace,
1200℃ in vacuum (10-2 to 10-Torr)
The sintering treatment was performed under ×oil conditions. The sintered body thus obtained had no seizure reaction. The magnetic properties after the optimum heat treatment are shown in the tX1 table.
比較例として従来法（Ｓｍ、 Ｏ，で被覆しない容器を
使用し、焼結温度を１１９５°Ｃとした）での密度と磁
気特性を示す。第１表から、本発明を適用することによ
り、高い密度が得られまた高磁気特性を有する希土類コ
バルト磁石合金が得られることがわかる。As a comparative example, the density and magnetic properties of a conventional method (a container not coated with Sm, O, and a sintering temperature of 1195°C) are shown. Table 1 shows that by applying the present invention, rare earth cobalt magnet alloys with high density and high magnetic properties can be obtained.
実施例２
８ｍ （Ｃｏｂａｌ Ｆｅα２５Ｃｕα０５５ Ｈｆα
０２）７５の組成を有するブロック状成形体（重さ７ｇ
）５を焼結する場合、第３図に示すような構造の焼結容
器を用いた。この焼結容器はモリブデン製の棚板６の上
面、ステンレス製の容器７の内面、７タ８には酸化サマ
リウムを溶射して製作した。この焼結容器内に成形体５
を第３図に示すように装填して、焼結炉に入れ水素ガス
雰囲気中で１１８５℃Ｘ２ｈの条件にて焼結処理を行な
った。このようにして焼結処理して得られた焼結体はモ
リブデン製の棚板との焼付反応は生じなかった。第２表
に熱処理後の磁気特性の測定結果を示す。Example 2 8m (Cobal Feα25Cuα055 Hfα
02) Block-shaped molded product having a composition of 75 (weight 7g
) 5, a sintering container having a structure as shown in FIG. 3 was used. This sintered container was manufactured by thermally spraying samarium oxide onto the upper surface of the molybdenum shelf board 6, the inner surface of the stainless steel container 7, and the container 7. A molded body 5 is placed in this sintering container.
were loaded as shown in FIG. 3, placed in a sintering furnace, and sintered at 1185° C. for 2 hours in a hydrogen gas atmosphere. The sintered body obtained by sintering in this manner did not cause any seizure reaction with the molybdenum shelf board. Table 2 shows the measurement results of magnetic properties after heat treatment.
比較例として従来法（Ｓｍ１０３の溶射なしない容器を
用い、焼結温度を１１８０℃とした）での結果も示す。As a comparative example, results obtained using a conventional method (using a container without thermal spraying of Sm103 and setting the sintering temperature at 1180° C.) are also shown.
第２表より本発明による方法により高特性な有する希土
類コバルト磁石合金が得られることがわかる。It can be seen from Table 2 that rare earth cobalt magnet alloys having high properties can be obtained by the method according to the present invention.
実施例３
Ｓｍｏ、ｓ Ｃｅｏ、ｓ （Ｃｏｂａｌ Ｆｅｏ、ｍ
Ｃｕｏ、ｏ６ｚｒｏ、ｏ＋ｓ） ７．４ ｔｎ組成を有
するリング状成形体（重さ５００ｇ）９を焼結する場合
に、第４図に示すような内面に酸化カルシウム１１を塗
布したチタン製の焼結容器１０に成形体９を装填して、
酸化カルシウム９１：塗布したチタン製の７タ１２を載
置した。この焼結容器を焼結炉に装入し水素ガス雰囲気
中で１１７０’ＣＸ２ｈで焼結を行なった。こうして焼
結処理した焼結体は焼付反応はなく均一に焼結できた。Example 3 Smo,s CEO,s (Cobal Feo,m
Cuo, o6zro, o+s) 7.4 When sintering a ring-shaped molded body (weight 500 g) 9 having a tn composition, a titanium sintered body coated with calcium oxide 11 on the inner surface as shown in Fig. 4 is used. Loading the molded body 9 into the container 10,
Calcium oxide 91: A coated titanium 7ta 12 was placed. This sintering container was placed in a sintering furnace and sintered at 1170'CX for 2 hours in a hydrogen gas atmosphere. The sintered body thus sintered could be sintered uniformly without any seizure reaction.
第３表に熱処理後の磁気特性を示す。Table 3 shows the magnetic properties after heat treatment.
比較例として従来法（ＣａＯ塗布なしの容器を用い、焼
結温度は１１７０°Ｃとした）での密度と磁気特性を示
す。第３表から本発明方法に従って焼結することにより
高い密度と高磁気特性を有する希土類コバルト磁石合金
が得られることがわかる。As a comparative example, the density and magnetic properties in a conventional method (a container without CaO coating was used, and the sintering temperature was 1170°C) are shown. Table 3 shows that rare earth cobalt magnet alloys having high density and high magnetic properties can be obtained by sintering according to the method of the present invention.
以上のように、本発明によれば、焼結容器を特定の醸化
物で被覆するため、焼結時の焼付反応を防止でき、かつ
得られた希土類コバルト磁石合金は従来法により得られ
た磁石合金に比べ高密度でかつ高磁気特性を有するので
、その工業的価値は極めて大である。As described above, according to the present invention, since the sintering container is coated with a specific compound, the sintering reaction during sintering can be prevented, and the obtained rare earth cobalt magnet alloy is different from the magnet obtained by the conventional method. Since it has higher density and higher magnetic properties than alloys, its industrial value is extremely large.
ｔＸ１図は一般的な希土類を主とした醸化物生成標準エ
ネルギーと温度の関係を示す図、第２図。
第３図、第４図は本発明に使用する焼結容器の断面図で
ある。
ｉ、５，９ ：成形体、 ２：モリブデン製焼結
ｄ器、３二酸化サマリウム粉末、４：モリブデン製フタ
、６：酸化サマリウム溶射モリブデン製板、７二酸化サ
マリウム溶射ステンレス製箱、８：酸化サマリウム溶射
ステンレス製フタ、１０：チタン製箱、
１１：酸化カルシウム粉末、
１２：チタン製フタ。
第 １ コ
第２０
馬４０The tX1 diagram is a diagram showing the relationship between standard energy and temperature for producing a common rare earth-based ferment, Figure 2. 3 and 4 are cross-sectional views of the sintered container used in the present invention. i, 5, 9: Molded body, 2: Molybdenum sintered device, 3 Samarium dioxide powder, 4: Molybdenum lid, 6: Samarium oxide sprayed molybdenum plate, 7 Samarium dioxide sprayed stainless steel box, 8: Samarium oxide Sprayed stainless steel lid, 10: Titanium box, 11: Calcium oxide powder, 12: Titanium lid. 1st Co. 20th Horse 40
Claims (1)
を焼結容器内に装填し、該焼結容器を焼結炉内に保持し
て焼結する希土類コバルト磁石の製造方法において、前
記焼結容器の内面を焼結時に発生する希土類蒸気により
還元されずかつ焼結の進行を阻害しない酸化物で被覆し
、当該焼結容器内に前記成形体を装填することを特徴と
する希土類コバルト磁石の製造方法。 ２、酸化物として希土類酸化物、ＭｇＯ又はＣａＯの内
から選ばれた１種類を用いる特許請求の範囲第１項記載
の希土類コバルト磁石の製造方法。[Claims] 1. A rare earth cobalt magnet in which rare earth cobalt alloy powder is molded, the resulting compact is loaded into a sintering container, and the sintering container is held in a sintering furnace for sintering. In the manufacturing method, the inner surface of the sintering container is coated with an oxide that is not reduced by rare earth vapor generated during sintering and does not inhibit the progress of sintering, and the molded body is loaded into the sintering container. A manufacturing method for rare earth cobalt magnets. 2. The method for producing a rare earth cobalt magnet according to claim 1, using one selected from rare earth oxides, MgO, and CaO as the oxide.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59241057A JPS61119009A (en) | 1984-11-15 | 1984-11-15 | Manufacture of rare-earth cobalt magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59241057A JPS61119009A (en) | 1984-11-15 | 1984-11-15 | Manufacture of rare-earth cobalt magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61119009A true JPS61119009A (en) | 1986-06-06 |
Family
ID=17068664
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59241057A Pending JPS61119009A (en) | 1984-11-15 | 1984-11-15 | Manufacture of rare-earth cobalt magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61119009A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02272711A (en) * | 1989-04-14 | 1990-11-07 | Hitachi Metals Ltd | Manufacture of r-tm-b radial anisotropic magnet |
| WO2003005383A1 (en) * | 2001-07-02 | 2003-01-16 | Sumitomo Special Metals Co., Ltd. | Method for producing rare earth sintered magnets |
| US6548014B2 (en) | 2000-06-21 | 2003-04-15 | Sumitomo Special Metals Co., Ltd. | Suspension application apparatus and method for manufacturing rare earth magnet |
| JP2014145129A (en) * | 2013-01-29 | 2014-08-14 | Yantai Shougang Magnetic Materials Inc | Method of manufacturing r-t-b-m-c-based sintered magnet, magnet manufactured by the method, and manufacturing device |
-
1984
- 1984-11-15 JP JP59241057A patent/JPS61119009A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02272711A (en) * | 1989-04-14 | 1990-11-07 | Hitachi Metals Ltd | Manufacture of r-tm-b radial anisotropic magnet |
| US6548014B2 (en) | 2000-06-21 | 2003-04-15 | Sumitomo Special Metals Co., Ltd. | Suspension application apparatus and method for manufacturing rare earth magnet |
| WO2003005383A1 (en) * | 2001-07-02 | 2003-01-16 | Sumitomo Special Metals Co., Ltd. | Method for producing rare earth sintered magnets |
| US7014811B2 (en) | 2001-07-02 | 2006-03-21 | Neomax Co., Ltd. | Method for producing rare earth sintered magnets |
| JP2014145129A (en) * | 2013-01-29 | 2014-08-14 | Yantai Shougang Magnetic Materials Inc | Method of manufacturing r-t-b-m-c-based sintered magnet, magnet manufactured by the method, and manufacturing device |
| US9672980B2 (en) | 2013-01-29 | 2017-06-06 | Yantai Shougang Magnetic Materials Inc. | R-T-B-M-C sintered magnet and production method and an apparatus for manufacturing the R-T-B-M-C sintered magnet |
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