JPH056814A - Manufacture of rare earth bond magnet - Google Patents

Abstract

PURPOSE:To provide the method for manufacturing a rare earth bond magnet which not only exhibits an excellent magnetic performance and a nice tempera ture characteristic though it does not contain hydrogen, but which has a suffi cient heat resistance. CONSTITUTION:At least one of Sn, Zn, Pb, In, Al, and Mg is added and mixed into alloy powder which is composed mainly of rare earth metal (R), Fe, N and/or C that contains a Th, Mn12-type compound as a main phase. This mixed power is molded by compression and is heat-treated at 100-600 deg.C.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、希土類ボンド磁石の製
造方法に係り、特に希土類金属（Ｒ）、鉄および窒素ま
たは炭素を含みかつＴｈＭｎ₁₂型正方晶化合物を主相と
して含む合金粉末を用いた希土類ボンド磁石の製造方法
に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a rare earth bonded magnet, and more particularly to an alloy powder containing a rare earth metal (R), iron and nitrogen or carbon and containing a ThMn ₁₂ type tetragonal compound as a main phase. The present invention relates to a method for manufacturing a rare earth bonded magnet.

【０００２】[0002]

【従来の技術】近年、各種電子部品・機器の小型化にと
もなって高性能な永久磁石が要求されている。1980年代
に開発されたＮd −Ｆe −Ｂ系永久磁石は高い磁気性能
を有し、かつそれ以前に開発されたＳm −Ｃo 系永久磁
石と比較して豊富で安価な原料で構成されているなどの
理由により工業的に広く利用されつつある。2. Description of the Related Art In recent years, with the miniaturization of various electronic parts and equipment, high-performance permanent magnets have been required. The Nd-Fe-B system permanent magnets developed in the 1980s have high magnetic performance and are composed of abundant and inexpensive raw materials as compared with the Sm-Co system permanent magnets developed before that. For this reason, it is being widely used industrially.

【０００３】ところで、このＮd −Ｆe −Ｂ系永久磁石
は、キュリー点が約300 ℃と低いために温度特性が悪
く、150 ℃以上となるような雰囲気での使用は不向きと
されている。この対策としてＦe の一部をＣo で置換し
たり、Ｎd の一部をＤy で置換することも行われている
が、実際上温度特性の改良は困難な状況にあった。By the way, the Nd-Fe-B system permanent magnet has a low Curie point of about 300.degree. C. and thus has poor temperature characteristics, and is not suitable for use in an atmosphere of 150.degree. As a countermeasure against this, a part of Fe is replaced by Co and a part of Nd is replaced by Dy, but it is actually difficult to improve the temperature characteristics.

【０００４】そこで最近、希土類金属−鉄−窒素−水素
系合金が磁石材料になり得ることが報告されている（例
えば、特開平２−57663 号公報参照）。これによれば、
合金中に窒素と水素とが共存した場合に、Ｎd −Ｆe−
Ｂ系永久磁石と同等の飽和磁束密度とそれ以上の高いキ
ュリー点が期待できるとしている。Therefore, it has recently been reported that a rare earth metal-iron-nitrogen-hydrogen alloy can be used as a magnet material (see, for example, Japanese Patent Application Laid-Open No. 2-57663). According to this
When nitrogen and hydrogen coexist in the alloy, Nd-Fe-
It is said that a saturation magnetic flux density equivalent to that of B-system permanent magnets and a higher Curie point higher than that can be expected.

【０００５】[0005]

【発明が解決しようとする課題】しかし、上記希土類金
属−鉄−窒素−水素系永久磁石によれば、合金中の水素
が温度や圧力の変化によって比較的容易に放出、吸蔵現
象を起こすため、長期的に磁気特性が不安定になり易
く、その上、引火爆発の危険性ある水素ガスあるいはア
ンモニア分解ガスを取り扱うために、製造性に難点があ
るという問題があった。またこの永久磁石をボンド磁石
として提供する場合、非磁性のエポキシ樹脂、フェノー
ル樹脂等をバインダーとして用いる従来の製造方法で
は、磁気性能特に保磁力の低下が避けらず、しかも耐熱
強度が不足して温度特性に優れるというせっかくの利点
が失われる、という問題もあった。However, according to the above rare earth metal-iron-nitrogen-hydrogen permanent magnet, hydrogen in the alloy is relatively easily released and occludes due to changes in temperature and pressure. There is a problem that the magnetic properties are likely to be unstable for a long period of time, and in addition, since hydrogen gas or ammonia decomposition gas, which has a risk of ignition and explosion, is handled, there is a problem in productivity. When this permanent magnet is provided as a bonded magnet, the conventional manufacturing method using a non-magnetic epoxy resin, phenol resin, etc. as a binder cannot avoid a decrease in magnetic performance, especially a coercive force, and has insufficient heat resistance. There is also a problem that the special advantage of excellent temperature characteristics is lost.

【０００６】本発明は、上記従来の問題に鑑みてなされ
たもので、水素を含まなくても優れた磁気性能と温度特
性とを確保でき、しかも十分なる耐熱性を有する希土類
ボンド磁石の製造方法を提供することを目的とする。The present invention has been made in view of the above conventional problems, and is a method for producing a rare-earth bonded magnet which can secure excellent magnetic performance and temperature characteristics without containing hydrogen and has sufficient heat resistance. The purpose is to provide.

【０００７】[0007]

【課題を解決するための手段】上記目的を達成するた
め、本発明にかゝる希土類ボンド磁石の製造方法は、希
土類金属（Ｒ）、Ｆe およびＮまたはＣを主成分としか
つＴh Ｍn ₁₂型正方晶化合物を主相として含む合金粉末
に、Ｓn ，Ｚn ，Ｐb ，Ｉn ，Ａl ，Ｍg の少なくとも
一種から成る金属粉末を２〜30重量％添加混合し、この
混合粉末を圧縮成形した後、 100〜600 ℃の温度範囲で
熱処理を行うようにしたことを特徴とする。In order to achieve the above-mentioned object, a method for producing a rare earth bonded magnet according to the present invention comprises a rare earth metal (R), Fe and N or C as a main component and a Th Mn ₁₂ type. 2 to 30% by weight of a metal powder containing at least one of Sn, Zn, Pb, In, Al and Mg is added to an alloy powder containing a tetragonal compound as a main phase and mixed, and the mixed powder is compression molded. It is characterized in that the heat treatment is carried out in a temperature range of up to 600 ° C.

【０００８】本発明において、上記合金粉末中のＦe は
その一部をＣo，Ｔi ，Ｖ，Ｓi 等の他の遷移金属で置
換しても良いもので、Ｆe の一部をＣo で置換した場合
はキュリー点の大幅な向上に寄与し、Ｆe の一部をＴ
ｉ，Ｖ，Ｓｉ等で置換した場合はＴh Ｍn ₁₂型化合物相
の構造安定化に寄与する。また上記圧縮成形は100 ℃以
上の加熱雰囲気下で行うことができ、さらに、圧縮成形
または熱処理後の磁石素材表面に、金属または有機物の
耐食性皮膜を形成するようにしても良いものである。In the present invention, Fe in the alloy powder may be partially replaced with another transition metal such as Co, Ti, V, and Si. In the case where a part of Fe is replaced with Co. Contributes to a significant improvement in the Curie point, and a part of Fe is
Substitution with i, V, Si, etc. contributes to the structural stabilization of the Th Mn ₁₂ type compound phase. The compression molding can be performed in a heating atmosphere at 100 ° C. or higher, and a metal or organic corrosion resistant coating may be formed on the surface of the magnet material after compression molding or heat treatment.

【０００９】また本発明において、上記Ｔh Ｍn ₁₂型正
方晶化合物は、一般に希土類金属と遷移金属との合金に
おいて認められる各種の化合物の内の一種であり、希土
類金属と遷移金属との原子比率が概略 8：92の領域を中
心として多く存在する。ただし、同じ型の化合物でも、
Ｓm Ｆe ₁₁Ｔｉ，Ｓm Ｆe ₁₀Ｖ₂ を主相として含む合金
は、高い保磁力をもつ反面、飽和磁束密度が低く表れ、
実用には向かない。In the present invention, the Th Mn ₁₂ type tetragonal compound is one of various compounds generally found in alloys of rare earth metals and transition metals, and has an atomic ratio of rare earth metals to transition metals. There are many around the 8:92 area. However, even with the same type of compound,
The alloy containing Sm Fe ₁₁ Ti and Sm Fe ₁₀ V ₂ as the main phase has a high coercive force but shows a low saturation magnetic flux density.
Not suitable for practical use.

【００１０】本発明は、上記Ｔh Ｍn ₁₂型正方晶化合物
を主相とする希土類金属−遷移金属系合金に、窒素また
は炭素を侵入させることによって飽和磁束密度を高めよ
うとするものである。しかしこの場合、例えば単純にＳ
m Ｆe ₁₁Ｔｉに窒素を侵入させると、結晶磁気異方性が
面内となって磁石材料にならず、一軸の結晶磁気異方性
を付与するためには、希土類金属としてＮd ，Ｐr ，Ｃ
e 等を用いるのが望ましい。これら希土類金属は、合金
中に占める割合が原子百分率（at％）で３％未満では保
磁力が減少し、12％を越えると飽和磁束密度あるいは残
留磁束密度が小さくなって実用的な永久磁石になりにく
いばかりか、合金中にＴh Ｍn ₁₂化合物以外の例えばα
Ｆe もしくはＲ₂ Ｆe ₁₇化合物等が多く現れ磁気特性の
低下をもたらすので、その割合を３〜20at％とするのが
望ましい。The present invention is intended to increase the saturation magnetic flux density by infiltrating nitrogen or carbon into the rare earth metal-transition metal alloy having the above-mentioned Th Mn ₁₂ type tetragonal compound as the main phase. However, in this case, for example, simply S
When nitrogen is introduced into m Fe ₁₁ Ti, the crystal magnetic anisotropy becomes in-plane and does not become a magnet material, and in order to impart uniaxial crystal magnetic anisotropy, Nd, Pr, and C are used as rare earth metals.
It is desirable to use e, etc. The coercive force of these rare earth metals decreases if the proportion of the rare earth metal in the alloy is less than 3% in atomic percentage (at%), and if it exceeds 12%, the saturation magnetic flux density or the residual magnetic flux density becomes small and it becomes a practical permanent magnet. In addition to being difficult to form, alloys other than Th Mn ₁₂ compounds such as α
A large amount of Fe or R ₂ Fe ₁₇ compound and the like appears, resulting in deterioration of magnetic properties. Therefore, the ratio is preferably 3 to 20 at%.

【００１１】ＮあるいはＣについては、Ｔh Ｍn ₁₂型化
合物の結晶格子内に侵入して、飽和磁束密度や、キュリ
ー点および結晶磁気異方性を増大させる働きがある。こ
れらＮあるいはＣの合金中における含有量は、２〜20at
％の範囲が所望の磁気特性を得るのに好適である。なお
ＮおよびＣは、それぞれ単独もしくは複合して含有させ
ても同様な磁気特性が期待できる。N or C penetrates into the crystal lattice of the Th Mn ₁₂ type compound to increase the saturation magnetic flux density, the Curie point and the crystal magnetic anisotropy. The content of these N or C in the alloy is 2 to 20 at
The range of% is suitable for obtaining the desired magnetic properties. Similar magnetic properties can be expected when N and C are contained alone or in combination.

【００１２】本発明において、上記合金粉末に添加する
金属粉末はバインダーとしても機能するもので、 100〜
600 ℃の比較的低温度でＦeと化合物または合金をつく
る特性を有している。しかして、これら金属粉末の合金
粉末への添加量は、２重量（wt）％未満では磁石として
の結合力が不足し、30％を越える場合には残留磁束密度
の低下を招くので、これを２〜30wt％とした。また、熱
処理温度として 100〜600 ℃を選択したのは、100 ℃未
満では前記バインダーとしての金属と合金粉末中に含ま
れる鉄との反応が行われないために保磁力の向上が期待
できず、逆に600 ℃を越えるとＴh Ｍn ₁₂相の分解のた
めに高い磁気特性が得られなくなる理由による。In the present invention, the metal powder added to the above-mentioned alloy powder also functions as a binder.
It has the property of forming a compound or an alloy with Fe at a relatively low temperature of 600 ° C. However, if the addition amount of these metal powders to the alloy powder is less than 2% by weight (wt), the binding force as a magnet will be insufficient, and if it exceeds 30%, the residual magnetic flux density will decrease. It was set to 2 to 30 wt%. Further, the heat treatment temperature is selected to be 100 to 600 ° C. The reason is that if the temperature is less than 100 ° C., the reaction between the metal as the binder and the iron contained in the alloy powder is not performed, and therefore the improvement of the coercive force cannot be expected, On the contrary, when the temperature exceeds 600 ° C., the high magnetic properties cannot be obtained due to the decomposition of the Th Mn ₁₂ phase.

【００１３】本発明において、上記合金粉末を得る方法
は任意であり、例えば希土類金属と鉄とを含む粉末（粒
径：数μm 〜数十μm ）を製造した後、この粉末を窒化
ガスまたは浸炭性ガスと接触させて（いわゆる窒化また
は浸炭処理を行って）、所望の窒素または炭素を該粉末
中に侵入させる方法を採用することができる。この場
合、前記希土類金属と鉄とを含む粉末を得るには、これ
らの合金インゴットをジョークラッシャー、ボールミル
等により機械的に粉砕する方法、合金溶湯を回転するロ
ール面へ直接射出する急冷法、合金溶湯をガスや液中に
高速で噴射させるアトマイズ法、溶解に代えて固体金属
同士の相互拡散を利用するメカニカルアロイング法等を
採用することができる。また、前記窒化処理は、窒化温
度として 300〜500 ℃を選択するのが良く、さらに窒素
の侵入を促進するため、10気圧以上の加圧雰囲気で行う
ようにしても良い。また浸炭処理としては、吸熱型変成
ガスを用いる汎用のガス浸炭法、固体浸炭剤を用いる固
体浸炭法、有機溶剤滴下式浸炭法、減圧された真空炉に
炭化水素系ガスを導入して行う真空浸炭法等を採用する
ことができる。In the present invention, any method may be used to obtain the above-mentioned alloy powder. For example, after a powder containing rare earth metal and iron (particle size: several μm to several tens μm) is produced, this powder is nitrided or carburized. It is possible to employ a method of bringing desired nitrogen or carbon into the powder by bringing it into contact with a neutral gas (so-called nitriding or carburizing treatment). In this case, in order to obtain a powder containing the rare earth metal and iron, a method of mechanically crushing these alloy ingots with a jaw crusher, a ball mill, a quenching method of directly injecting a molten alloy into a rotating roll surface, an alloy An atomizing method of injecting the molten metal into gas or liquid at high speed, a mechanical alloying method of utilizing mutual diffusion of solid metals instead of melting, and the like can be adopted. Further, the nitriding treatment is preferably performed at a nitriding temperature of 300 to 500 [deg.] C., and in order to promote the penetration of nitrogen, it may be performed in a pressurized atmosphere of 10 atm or more. Further, as the carburizing treatment, a general-purpose gas carburizing method using an endothermic shift gas, a solid carburizing method using a solid carburizing agent, an organic solvent dropping type carburizing method, a vacuum performed by introducing a hydrocarbon-based gas into a depressurized vacuum furnace A carburizing method or the like can be adopted.

【００１４】また本発明において、上記圧縮成形する方
法も任意であり、例えば合金粉末にバインダーとしての
金属粉末を所定量加えて混合した後、プレス金型に供給
して１〜10 Ton／cm² の圧力で圧縮成形する方法、ある
いは静水圧加圧装置を用いる方法を採用することができ
る。なお前記圧縮成形を100 ℃以上の加熱雰囲気下で行
うことにより、後工程の熱処理を省略または簡略化する
こともできる。In the present invention, the compression molding method may be any method. For example, a predetermined amount of a metal powder as a binder is added to an alloy powder and mixed, and then the mixture is supplied to a press die to be 1 to 10 Ton / cm ^2. It is possible to employ a method of compression molding at a pressure of 1, or a method of using a hydrostatic pressure device. By performing the compression molding in a heating atmosphere of 100 ° C. or higher, the heat treatment in the subsequent step can be omitted or simplified.

【００１５】[0015]

【作用】上記のように構成した希土類ボンド磁石の製造
方法においては、窒素または炭素がＴh Ｍn ₁₂型金属間
化合物の結晶格子内に侵入し、磁気性能を高めかつキュ
リー点を上昇させる。また、水素を含まないので長期に
わたって性能が安定する。しかも製造過程で水素を取り
扱うことがないので安全性が高まる。また、鉄と化合物
または合金をつくり易い金属をバインダーとして用いた
ので、磁気性能がより一層向上するばかりか、結合力も
増大して耐熱性が向上する。In the method for producing a rare earth bonded magnet constructed as described above, nitrogen or carbon penetrates into the crystal lattice of the Th Mn ₁₂ type intermetallic compound to enhance the magnetic performance and raise the Curie point. In addition, since it does not contain hydrogen, the performance is stable over a long period of time. Moreover, since hydrogen is not handled in the manufacturing process, safety is enhanced. In addition, since a metal that easily forms a compound or an alloy with iron is used as the binder, not only the magnetic performance is further improved, but also the binding force is increased and the heat resistance is improved.

【００１６】[0016]

【実施例】以下、本発明の実施例を説明する。EXAMPLES Examples of the present invention will be described below.

【００１７】実施例１ 純度99％以上のネオジウム（Ｎd ）、電解鉄およびスポ
ンジチタンを所定の比率で配合し、アルミナルツボに装
入して高周波誘導炉によって溶解し、鋳型内に鋳込んで
合金インゴットを製作した。この合金インゴット内部に
は多くの場合成分偏析がみられるため、これをアルゴン
ガス雰囲気下で1100℃、24時間保持してその後急冷する
熱処理を行った。次に，この合金インゴットをジョーク
ラッシャーとスタンプミルによって粉砕して、50〜200
μm の粉末を得、続いてこの粉末をステンレス製小皿に
入れて電気炉に装入し、窒素ガス雰囲気下で、400 ℃、
１〜24時間保持して窒素を侵入せしめ、その後ボールミ
ルにより再度粉砕して平均粒径20μm の合金粉末を得
た。Example 1 Neodymium (Nd) with a purity of 99% or more, electrolytic iron and titanium sponge were blended in a predetermined ratio, charged in an alumina crucible and melted in a high frequency induction furnace, and cast in a mold to form an alloy. I made an ingot. In many cases, segregation of components was observed inside the alloy ingot, so this was heat-treated by holding it in an argon gas atmosphere at 1100 ° C for 24 hours and then rapidly cooling it. Next, this alloy ingot was crushed with a jaw crusher and a stamp mill to obtain 50 to 200
μm powder was obtained, and then this powder was placed in a stainless steel small plate and placed in an electric furnace.
It was kept for 1 to 24 hours to allow nitrogen to infiltrate, and then pulverized again by a ball mill to obtain an alloy powder having an average particle size of 20 μm.

【００１８】次に、上記合金粉末に粒径約10μm の亜鉛
粉末12重量％を添加してボールミルにより混合し、この
混合粉末を15ｋＯeの磁界を印加しながら５ Ton／cm²
の圧力で圧縮成形した。その後、この成形体を電気炉に
装入して、窒素ガス雰囲気中400 ℃で１時間の熱処理を
行って磁石試料１〜１０を製作し、これらを磁気特性お
よびキュリー点の測定試験に供した。また同時に、所定
成分組成のＮd −Ｆe−Ｂ焼結体を粉砕して得た粒径30
〜150 μm の粉末圧縮成形して比較例試料１１を得ると
共に、所定成分組成のＳm −Ｃo−Ｆe −Ｃu −Ｚr 合
金を熱処理・粉砕・成形したものを比較例試料１２と
し、これらも前記した各種試験に供した。なお、各種測
定試験に先立って各試料の結晶構造をＸ線回折法によっ
て解析した結果、磁石試料１〜１０にはいずれも主とし
てＴh Ｍn ₁₂化合物の存在が認められた。Next, 12% by weight of zinc powder having a particle size of about 10 μm was added to the above alloy powder and mixed by a ball mill, and this mixed powder was applied at 5 Ton / cm ² while applying a magnetic field of 15 kOe.
It was compression molded at a pressure of. Then, this molded body was placed in an electric furnace and heat-treated in a nitrogen gas atmosphere at 400 ° C. for 1 hour to manufacture magnet samples 1 to 10, which were subjected to a magnetic characteristic and Curie point measurement test. . At the same time, the Nd-Fe-B sintered body having the predetermined composition was crushed to obtain a particle size of 30
Comparative sample 11 was obtained by compression-compacting powder of ˜150 μm, and a sample of Sm—Co—Fe—Cu—Zr alloy having a predetermined composition was heat treated, crushed and molded to form comparative sample 12, which was also described above. It was subjected to various tests. As a result of analyzing the crystal structure of each sample by an X-ray diffraction method prior to various measurement tests, the presence of Th Mn ₁₂ compound was mainly found in each of the magnet samples 1 to 10.

【００１９】磁気特性の測定は、60ｋＯe のパルス磁界
を印加した後、直流式ＢＨトレーサーによって行い、キ
ュリー点の測定は振動試料型磁力計（略称ＶＳＭ）を用
いて行った。また成分分析は、Ｎd 、Ｆe およびＴi に
ついてはＩＣＰ発光分析法により、Ｎについては蒸留中
和滴定法によりそれぞれ行った。これらの試験結果を表
１に示す。なお、表中、Ｂr は残留磁束密度を、ｉＨc
は保磁力を、Ｔc はキュリー点をそれぞれ表しており、
また試料番号に付した符号＃は比較例を表している。The magnetic characteristics were measured with a DC BH tracer after applying a pulsed magnetic field of 60 kOe, and the Curie point was measured with a vibrating sample magnetometer (abbreviated as VSM). The component analysis was carried out by ICP emission spectrometry for Nd, Fe and Ti and by distillation neutralization titration for N. The results of these tests are shown in Table 1. In the table, Br is the residual magnetic flux density, iHc
Is the coercive force, Tc is the Curie point,
The symbol # attached to the sample number indicates a comparative example.

【００２０】[0020]

【表１】 [Table 1]

【００２１】表１から明らかなように、本発明にかゝる
磁石試料２〜４および７〜９は、いずれも残留磁束密度
Ｂr 、保磁力ｉＨc 、キュリー点Ｔc とも高い値が得ら
れた。またキュリー点Ｔc については、Ｎd−Ｆe −Ｂ
系磁石試料１１と比較しても高い値となることが明らか
になった。なお、Ｎ含有量の過小な磁石試料１は、合金
粉末が一軸の結晶磁気異方性を持たないために保磁力ｉ
Ｈc が他に比してきわめて小さい。またＮd含有量の少
ない磁石試料６の保磁力ｉＨc が他に比して小さい理由
は、Ｘ線回折によれば合金中に多量に存在するαＦe が
その原因になったものと推察される。またＮ、Ｎd を過
剰に含有する磁石試料５、１０は、それぞれ保磁力ｉＨ
c が低下すると同時に、合金中のＦe 含有量の減少のた
め残留磁束密度Ｂr も低下している。さらに比較例試料
１１における低保磁力は、Ｎd −Ｆe −Ｂ系焼結体を粉
砕する場合にみられる特有の現象である。比較例試料１
２は高いキュリー点Ｔc を示すものの、残留磁束密度Ｂ
r において本発明にかゝる磁石試料には及ばない。As is clear from Table 1, in the magnet samples 2 to 4 and 7 to 9 according to the present invention, the residual magnetic flux density Br, the coercive force iHc and the Curie point Tc were all high. For the Curie point Tc, Nd-Fe-B
It was revealed that the value was higher than that of the system magnet sample 11. The magnet sample 1 having an excessively low N content has a coercive force i because the alloy powder does not have uniaxial crystal magnetic anisotropy.
Hc is extremely small compared to others. Also, the reason why the coercive force iHc of the magnet sample 6 having a small Nd content is smaller than the others is presumed to be that a large amount of αFe existing in the alloy is the cause by X-ray diffraction. Further, the magnet samples 5 and 10 containing N and Nd in excess contain coercive force iH, respectively.
At the same time as c decreases, the residual magnetic flux density Br also decreases due to the decrease in the Fe content in the alloy. Furthermore, the low coercive force in Comparative Example Sample 11 is a unique phenomenon observed when crushing an Nd-Fe-B system sintered body. Comparative example sample 1
2 shows a high Curie point Tc, but the residual magnetic flux density B
At r, it does not reach the magnet sample according to the present invention.

【００２１】実施例２ 純度99％以上のプラセオジウム（Ｐr ）、電解鉄、コバ
ルト、スポンジチタンおよび4.3 ％の炭素を含有する銑
鉄とを所定の比率で配合し、溶解して得たインゴットを
粉砕して、平均粒径20μm の粉末を得た。続いて実施例
１と同一の手順により、窒化処理、亜鉛粉末添加、圧縮
成形、熱処理を行って磁石試料２１〜２４を製作し、こ
れらを実施例１と同様の磁気特性の測定試験に供した。
結果を表２に示す。Example 2 Praseodymium (Pr) having a purity of 99% or more, electrolytic iron, cobalt, titanium sponge and pig iron containing 4.3% of carbon were blended in a predetermined ratio, and the ingot obtained by melting was crushed. Thus, a powder having an average particle size of 20 μm was obtained. Subsequently, by the same procedure as in Example 1, nitriding treatment, addition of zinc powder, compression molding, and heat treatment were performed to manufacture magnet samples 21 to 24, which were subjected to the same magnetic characteristic measurement test as in Example 1. .
The results are shown in Table 2.

【００２２】[0022]

【表２】 [Table 2]

【００２３】表２から明らかなように、本発明にかかる
磁石試料２１〜２４はいずれも良好な磁気特性が得ら
れ、合金中にコバルトを含有することによってキュリー
点Ｔcが向上する傾向を示す。また合金中に、窒素の代
わりに炭素を含有しても所望の磁気特性を得られること
が確認できた。As is apparent from Table 2, all of the magnet samples 21 to 24 according to the present invention have good magnetic properties, and the inclusion of cobalt in the alloy tends to improve the Curie point Tc. It was also confirmed that desired magnetic properties could be obtained even if carbon was contained in the alloy instead of nitrogen.

【００２３】実施例３ 実施例１と同様に、ネオジウム、電解鉄およびスポンジ
チタンとから合金インゴットを製作し、粉砕、窒化、再
粉砕して、試料番号８と同一成分組成を有する平均粒径
20μm の粉末を得た。次にこの粉末に粒径約10μmの亜
鉛粉末を種々の割合で添加混合し、実施例１と同様に圧
縮成形し、窒素ガス中で種々の温度に１時間保持する熱
処理を行って磁石試料３１〜４２を製作し、これらを実
施例１と同様の磁気特性の測定試験に供した。それらの
結果を表３に示す。Example 3 Similar to Example 1, an alloy ingot was prepared from neodymium, electrolytic iron and titanium sponge, crushed, nitrided and re-crushed to have an average particle size having the same composition as sample No. 8.
20 μm powder was obtained. Next, to this powder, zinc powder having a particle diameter of about 10 μm was added and mixed at various ratios, compression-molded in the same manner as in Example 1, and subjected to heat treatment in nitrogen gas at various temperatures for 1 hour to obtain magnet sample 31. To 42 were manufactured and subjected to the same magnetic characteristic measurement test as in Example 1. The results are shown in Table 3.

【００２４】[0024]

【表３】 [Table 3]

【００２５】表３から明らかなように、本発明にかゝる
磁石試料３２〜３５および３８〜４１はいずれも残留磁
束密度Ｂr 、保磁力ｉＨc とも高い値を示し、亜鉛混合
量２〜30重量％および熱処理温度 100〜600 ℃の範囲に
おいて優れた磁気特性が得ることができた。なお比較例
試料４１は、保磁力ｉＨc がやや低いとともに、結合剤
として機能する亜鉛を含まないために磁石強度が低く、
磁気測定中に磁石試料の割れを生じるため実用に供し得
ないことが明らかとなった。また亜鉛混合量の過剰な比
較例試料３６は、残留磁束密度Ｂr が低下して従来のＳ
m ₂ Ｃo ₁₇系磁石の水準になっている。さらに、熱処理
をしない比較例試料３７および熱処理温度が高すぎる比
較例試料４２は低い保磁力ｉＨc を示しており、特に試
料４２については、化合物の分解とそれにともなう鉄と
亜鉛の反応により保磁力が急減している。As is apparent from Table 3, all of the magnet samples 32 to 35 and 38 to 41 according to the present invention have high residual magnetic flux density Br and coercive force iHc, and the zinc content is 2 to 30% by weight. %, And excellent magnetic properties could be obtained in the range of 100 to 600 ° C. and the heat treatment temperature. The comparative sample 41 has a slightly low coercive force iHc and a low magnet strength because it does not contain zinc that functions as a binder.
It was clarified that the sample could not be put to practical use because the magnet sample was cracked during the magnetic measurement. Further, in the comparative sample 36 in which the amount of zinc mixed is excessive, the residual magnetic flux density Br decreases and the conventional S
It is at the level of m ₂ Co ₁₇ series magnets. Further, the comparative sample 37 without heat treatment and the comparative sample 42 whose heat treatment temperature is too high show a low coercive force iHc. Particularly, in the case of the sample 42, the coercive force is high due to the decomposition of the compound and the accompanying reaction of iron and zinc. It is decreasing sharply.

【００２６】実施例４ 実施例２における試料番号２２に用いた成分組成と同一
のＰr −Ｔｉ−Ｃo −Ｃ−Ｆe 合金粉末に、Ｓn ，Ｚn
，Ｐb ，Ｉn ，Ａl ，Ｍg あるいはそれらの合金粉末
をそれぞれ15重量％混合したものを、実施例１と同様に
成形した。続いてこれらの成形体を電気炉に装入して、
真空中で種々の温度に１時間保持する熱処理を行って磁
石試料５１〜５８を製作し、これを実施例１と同様の磁
気特性の測定試験に供した。それらの結果を表４に示
す。なお表４中の混合金属の数値は、合金の場合の重量
％を表している。Example 4 Sn, Zn was added to Pr-Ti-Co-C-Fe alloy powder having the same composition as the sample No. 22 used in Example 2.
, Pb, In, Al, Mg or alloy powders thereof were mixed by 15% by weight and molded in the same manner as in Example 1. Then, insert these molded bodies into an electric furnace,
Magnet samples 51 to 58 were manufactured by carrying out a heat treatment of holding at various temperatures in vacuum for 1 hour, and subjected to the same magnetic characteristic measurement test as in Example 1. The results are shown in Table 4. In addition, the numerical value of the mixed metal in Table 4 represents weight% in the case of alloy.

【００２７】[0027]

【表４】 [Table 4]

【００２８】表４から明らかなように、本発明にかかる
磁石試料５２〜５８はいずれも、残留磁束密度Ｂr ，保
磁力ｉＨc とも高い値が得られ、本発明において規定し
たいわゆる低融点金属・合金の使用が、磁気特性の向上
に効果あることが認められた。なお、比較例試料５１
は、熱処理を実施していないために保磁力ｉＨc が小さ
い。As is apparent from Table 4, all of the magnet samples 52 to 58 according to the present invention have high residual magnetic flux density Br and coercive force iHc, which are so-called low melting point metals and alloys defined in the present invention. It has been found that the use of is effective in improving the magnetic properties. Comparative sample 51
Has a small coercive force iHc because heat treatment is not performed.

【００２９】実施例５ 実施例１における試料番号８に用いた成分組成と同一の
Ｎd −Ｔｉ−Ｎ−Ｆe合金粉末に、５重量％の亜鉛と0.5
重量％のステアリン酸を混合した。この混合粉末を、
真空ホットプレスの350 ℃に加熱された金型に充填し、
10ｋＯe の磁界を印加しながら１ Ton／cm² の圧力で５
分間圧縮成形して磁石試料を製作し、これを実施例１と
同様の磁気特性の測定試験に供した。なお、試料の密度
は7.1 ｇ／cm³ であり、高温での加圧成形のため室温成
形の場合と比較して高い密度が得られた。測定試験の結
果、本試料は残留磁束密度Ｂr ＝9964（Ｇ）、保磁力ｉ
Ｈc ＝7863（Ｏe ）となり、優れた磁石特性が得られる
ことが明らかとなった。Example 5 Nd-Ti-N-Fe alloy powder having the same composition as that used for sample No. 8 in Example 1 was added with 5% by weight of zinc and 0.5% by weight.
Weight percent stearic acid was mixed. This mixed powder,
Fill the mold heated to 350 ℃ of vacuum hot press,
5 at a pressure of 1 Ton / cm ² while applying a magnetic field of 10 kOe
A magnet sample was manufactured by compression molding for one minute, and this was subjected to the same measurement test of magnetic properties as in Example 1. The density of the sample was 7.1 g / cm ³ , and a high density was obtained as compared with the case of room temperature molding because of pressure molding at high temperature. As a result of the measurement test, this sample has a residual magnetic flux density Br = 9964 (G) and a coercive force i.
Since Hc = 7863 (Oe), it is clear that excellent magnet characteristics can be obtained.

【００３０】実施例６ 実施例４で製作した磁石体表面に、以下の３種類の方法
によりいずれも約20μm の皮膜を形成し、磁石試料６１
〜６３を製作した。すなわち、磁石試料６１はカチオン
系エポキシ樹脂を電着塗装する方法により、磁石試料６
２はフッ素系樹脂を自動機により吹き付け塗装する方法
により、磁石試料６３は電気ニッケルメッキを行う方法
によりそれぞれ製作した。なお、皮膜を形成しない磁石
体を比較例試料６４とした。次に、これらの試料６１〜
６４を、60℃、90％ＲＨ、500 時間の耐湿度試験に供し
て、錆の発生の有無を顕微鏡観察によって調査した。試
験結果を表５に示す。表５から明らかなように、比較例
試料６４は試料表面の皮膜が無いために錆易いものの、
本発明にかかる磁石試料６１〜６３はその表面に有機物
または金属の皮膜を有することにより、実用上充分な耐
食性を得ることができる。Example 6 A magnet sample 61 was prepared by forming a film of about 20 μm on each surface of the magnet body produced in Example 4 by the following three methods.
~ 63 made. That is, the magnet sample 61 was prepared by applying a cationic epoxy resin by electrodeposition coating.
2 was manufactured by a method of spraying and coating a fluorine-based resin by an automatic machine, and the magnet sample 63 was manufactured by a method of electrolytic nickel plating. A magnet body that does not form a film was used as Comparative Sample 64. Next, these samples 61 to
No. 64 was subjected to a humidity resistance test at 60 ° C. and 90% RH for 500 hours, and the presence or absence of rust was examined by microscopic observation. The test results are shown in Table 5. As is clear from Table 5, the sample 64 of the comparative example is easy to rust because there is no film on the surface of the sample.
Since the magnet samples 61 to 63 according to the present invention have organic or metal coatings on their surfaces, practically sufficient corrosion resistance can be obtained.

【００３１】[0031]

【表５】 [Table 5]

【００３２】[0032]

【発明の効果】以上、詳細に説明したように、本発明に
かゝる希土類ボンド磁石の製造方法によれば、その特有
の組成と化合物相の存在により、水素を含まなくても磁
気性能および温度特性に優れた磁石を製造できるように
なり、製造過程で危険な水素を取り扱うことがないの
で、製造の安全性を確立できる効果がある。また本製造
方法により得られた磁石は、水素を含まないので磁気性
能が長期的に安定し、しかも鉄と化合物または合金をつ
くり易い金属をバインダーとして用いることにより磁気
性能がより一層向上すると共に、結合力が増大して耐熱
性が高まり、耐久信頼性が著しく向上するようになる。As described above in detail, according to the method for producing a rare earth bonded magnet according to the present invention, due to its peculiar composition and the presence of the compound phase, the magnetic performance and Since it becomes possible to manufacture a magnet with excellent temperature characteristics and dangerous hydrogen is not handled in the manufacturing process, there is an effect that the manufacturing safety can be established. Further, the magnet obtained by the present production method does not contain hydrogen, so that the magnetic performance is stable for a long period of time, and further the magnetic performance is further improved by using a metal that easily forms a compound or an alloy with iron as a binder. The bonding strength is increased, the heat resistance is increased, and the durability reliability is significantly improved.

Claims (6)

【特許請求の範囲】[Claims] 【請求項１】 希土類金属（Ｒ）、Ｆe およびＮを主成
分としかつＴhＭn ₁₂型正方晶化合物を主相として含む
合金粉末に、Ｓn ，Ｚn ，Ｐb ，Ｉn ，Ａl，Ｍg の少
なくとも一種から成る金属粉末を２〜30重量％添加混合
し、この混合粉末を圧縮成形した後、 100〜600 ℃の温
度範囲で熱処理を行うことを特徴とする希土類ボンド磁
石の製造方法。1. An alloy powder containing a rare earth metal (R), Fe and N as main components and a ThMn ₁₂ type tetragonal compound as a main phase, and at least one of Sn, Zn, Pb, In, Al and Mg. A method for producing a rare earth bonded magnet, characterized in that 2 to 30% by weight of metal powder is added and mixed, the mixed powder is compression-molded, and then heat treated in a temperature range of 100 to 600 ° C. 【請求項２】 Ｎに代えてＣを含ませたことを特徴とす
る請求項１に記載の希土類ボンド磁石の製造方法。2. The method for producing a rare earth bonded magnet according to claim 1, wherein C is contained in place of N. 【請求項３】 Ｎの一部をＣで置換したことを特徴とす
る請求項１に記載の希土類ボンド磁石の製造方法。3. The method for producing a rare earth bonded magnet according to claim 1, wherein a part of N is replaced with C. 【請求項４】 Ｆe の一部を他の遷移金属で置換したこ
とを特徴とする請求項１に記載の希土類ボンド磁石の製
造方法。4. The method for producing a rare earth bonded magnet according to claim 1, wherein part of Fe is replaced with another transition metal. 【請求項５】 圧縮成形を100 ℃以上の加熱雰囲気下で
行うことを特徴とする請求項１乃至４の何れか１項に記
載の希土類ボンド磁石の製造方法。5. The method for producing a rare earth bonded magnet according to claim 1, wherein the compression molding is performed in a heating atmosphere at 100 ° C. or higher. 【請求項６】 圧縮成形または熱処理後の磁石素材表面
に、金属または有機物の耐食性皮膜を形成することを特
徴とする請求項１乃至４の何れか１項に記載の希土類ボ
ンド磁石の製造方法。6. The method for producing a rare earth bonded magnet according to claim 1, wherein a corrosion resistant coating of a metal or an organic material is formed on the surface of the magnet material after compression molding or heat treatment.