JP2016207677A - Sm-Fe-N BASED RARE EARTH MAGNET - Google Patents
Sm-Fe-N BASED RARE EARTH MAGNET Download PDFInfo
- Publication number
- JP2016207677A JP2016207677A JP2015083005A JP2015083005A JP2016207677A JP 2016207677 A JP2016207677 A JP 2016207677A JP 2015083005 A JP2015083005 A JP 2015083005A JP 2015083005 A JP2015083005 A JP 2015083005A JP 2016207677 A JP2016207677 A JP 2016207677A
- Authority
- JP
- Japan
- Prior art keywords
- phase
- smfe
- rare earth
- powder
- 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.)
- Granted
Links
Landscapes
- Hard Magnetic Materials (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
本発明は、Ｓｍ−Ｆｅ−Ｎ系希土類磁石に関するものである。 The present invention relates to an Sm—Fe—N rare earth magnet.
高性能希土類磁石としては、Ｓｍ−Ｃｏ系磁石やＮｄ−Ｆｅ−Ｂ系磁石が実用化されているが、近年、新規な希土類磁石の開発が盛んに行われている。 Sm—Co magnets and Nd—Fe—B magnets have been put to practical use as high performance rare earth magnets, but in recent years, new rare earth magnets have been actively developed.
例えば、Ｓｍ−Ｆｅ結晶にＮが侵入型に固溶したＳｍ−Ｆｅ−Ｎ系の希土類窒化磁石が提案されている。Ｓｍ−Ｆｅ−Ｎ系磁石はキュリー温度が高く、且つＮｄ−Ｆｅ−Ｂ系磁石と同等の磁気特性を示すことから、高耐熱性に優れた希土類磁石として、改良が進められている。 For example, Sm—Fe—N rare earth nitride magnets in which N is solid-dissolved in Sm—Fe crystals have been proposed. Since the Sm—Fe—N-based magnet has a high Curie temperature and exhibits the same magnetic characteristics as the Nd—Fe—B-based magnet, the improvement is being made as a rare earth magnet having excellent high heat resistance.
特許文献１では、２相分離型のＲｅ−Ｆｅ−Ｎ−Ｈ−Ｍ系磁石を提案している。Ｒｅは希土類元素であり、Ｍは、Ｌｉ、Ｎａ、Ｋ、Ｍｇ、Ｃａ、Ｓｒ、Ｂａ、Ｔｉ、Ｚｒ、Ｈｆ、Ｖ、Ｎｂ、Ｔａ、Ｃｒ、Ｍｏ、Ｗ、Ｍｎ、Ｐｄ、Ｃｕ、Ａｇ、Ｚｎ、Ｂ、Ａｌ、Ｇａ、Ｉｎ、Ｃ、Ｓｉ、Ｇｅ、Ｓｎ、Ｐｂ、Ｂｉの元素およびこれらの元素ならびに希土類元素の酸化物、フッ化物、炭化物、窒化物、水素化物、炭酸塩、硫酸塩、ケイ酸塩、塩化物、硝酸塩のうち少なくとも１種である。同公報では、Ｍ添加によりＳｍ−Ｃｏ系やＮｄ−Ｆｅ−Ｂ系でみられるような２相分離型の微構造を形成させ、これにより、焼結磁石やボンディッド磁石のようなバルク磁石としたときにも粉体のときと同様な高い磁気特性を引き出すことを目的としている。具体的には、粒子境界部にＭの含有量が多い相を有し、粒子中心部にはＭの含有量が少ないか、または、Ｍを含有しない相を有する２相分離型のバルク磁石を製造している。 Patent Document 1 proposes a two-phase separation type Re—Fe—N—H—M magnet. Re is a rare earth element, M is Li, Na, K, Mg, Ca, Sr, Ba, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Pd, Cu, Ag, Zn, B, Al, Ga, In, C, Si, Ge, Sn, Pb, Bi elements and oxides, fluorides, carbides, nitrides, hydrides, carbonates, sulfates of these elements and rare earth elements , At least one of silicate, chloride and nitrate. In the same publication, by adding M, a two-phase separation type microstructure as seen in the Sm—Co system and Nd—Fe—B system is formed, thereby forming a bulk magnet such as a sintered magnet or a bonded magnet. Sometimes it aims to bring out the same high magnetic properties as powder. Specifically, a two-phase separation type bulk magnet having a phase with a high M content at the particle boundary and a low M content or a phase not containing M at the center of the particle. Manufacture.
また、特許文献２では、このＲ−Ｔ系化合物中にＮ原子を混入したＳｍ２Ｆｅ１７ＮＸ等の含窒素希土類磁石は６００℃以上に加熱すると結晶構造がＲＮとα−Ｆｅに分解してしまうため、Ｎｄ−Ｆｅ−Ｂ 系合金等のように、１０００℃以上の高温と長時間を要する従来の高温液相焼結法やホットプレス法等の成形固化法を用いることができないという課題に対し、Ｒ−Ｔ−Ｎ合金粉末（Ｒは希土類元素，Ｔは遷移金属，Ｎは窒素）を所定の形状に成形し、その後この成形体を焼結して固形化する含窒素希土類磁石の製造方法において、上記成形体を、昇温速度６００〜１０００℃／ｍｉｎ、焼結温度５５０℃以下、焼結時間１分以内、焼結圧力６〜１０ｔｏｎ／ｃｍ２ 、電流密度０．７〜２．０ｋＡ／ｃｍ２の条件でプラズマ焼結する含窒素希土類磁石の製造方法が開示されている。 In Patent Document 2, a nitrogen-containing rare earth magnet such as Sm 2 Fe 17 N X in which N atoms are mixed in this RT compound is decomposed into RN and α-Fe when heated to 600 ° C. or higher. Therefore, it is difficult to use a conventional solidification method such as a high-temperature liquid phase sintering method or a hot press method that requires a high temperature of 1000 ° C. or more and a long time, such as an Nd—Fe—B alloy. In contrast, a nitrogen-containing rare earth magnet in which an R-TN alloy powder (R is a rare earth element, T is a transition metal, and N is nitrogen) is formed into a predetermined shape and then the formed body is sintered and solidified. In the production method, the molded body is heated at a heating rate of 600 to 1000 ° C./min, a sintering temperature of 550 ° C. or less, a sintering time within 1 minute, a sintering pressure of 6 to 10 ton / cm 2 , and a current density of 0.7 to 2 . to plasma sintering under the conditions of .0kA / cm 2 Method for producing nitrogen-containing rare earth magnet is disclosed.
Ｓｍ−Ｆｅ−Ｎ系磁石における磁気特性の一つである保磁力（Ｈｃｊ）の発生機構は、ニュークリエーションタイプであると言われている。その為、磁気特性が粒子の表面の影響を受け易い。すなわち、粉砕時の機械的衝撃や粒子の酸化等により磁石粒子表面には欠陥が生じ、この欠陥により磁壁が発生するが、ニュークリエーションタイプの磁石では結晶粒内に磁壁のピンニングサイトがないため容易に磁壁移動が起こるので、保磁力が劣化し易い。上記先行文献では、原料磁石粉末の作製の際にボールミル等での粉砕を行っている事から、酸化の影響により、低温かつ短時間のプラズマ焼結法であっても高い磁気特性を得ることができなかった。 It is said that the coercive force (H cj ) generation mechanism, which is one of the magnetic characteristics in the Sm—Fe—N based magnet, is a new creation type. For this reason, the magnetic properties are easily affected by the surface of the particles. That is, a defect is generated on the surface of the magnet particle due to mechanical impact at the time of pulverization, particle oxidation, etc., and a domain wall is generated by this defect. In this case, the domain wall movement occurs, so that the coercive force is easily deteriorated. In the above-mentioned prior literature, since the raw magnet powder is pulverized by a ball mill or the like, high magnetic properties can be obtained even by a low-temperature and short-time plasma sintering method due to oxidation. could not.
本発明は、上記の課題を解決するためになされたものであり、高い磁気特性、且つ高密度のＳｍ−Ｆｅ−Ｎ系希土類磁石を提供するものである。 The present invention has been made to solve the above-described problems, and provides a Sm—Fe—N rare earth magnet having high magnetic properties and high density.
Ｓｍ−Ｆｅ−Ｎ系希土類磁石の酸化による磁気特性劣化を抑制するためには、主相であるＳｍ２Ｆｅ１７Ｎ３相に加え、ＳｍＦｅ３Ｎｘ相を導入するが有効であることを見出し、本発明に至った。 In order to suppress the deterioration of the magnetic properties due to oxidation of the Sm-Fe-N rare earth magnet, it has been found effective to introduce the SmFe 3 N x phase in addition to the Sm 2 Fe 17 N 3 phase as the main phase. The present invention has been reached.
本発明にかかる希土類磁石は、相対密度９０％以上のＳｍ−Ｆｅ−Ｎ系希土類磁石であって、副相としてＳｍＦｅ３Ｎｘ相（１．０≦ｘ≦２．５）を断面積の面積比率で５％以下（０を含まず）含むことを特徴とするＳｍ−Ｆｅ−Ｎ系希土類磁石である。 The rare earth magnet according to the present invention is an Sm—Fe—N rare earth magnet having a relative density of 90% or more, and an SmFe 3 N x phase (1.0 ≦ x ≦ 2.5) is used as a subphase. It is an Sm—Fe—N rare earth magnet characterized by containing 5% or less (excluding 0) in proportion.
高い磁気特性、且つ高い相対密度のＳｍ−Ｆｅ−Ｎ系希土類磁石を提供することができる。 An Sm—Fe—N rare earth magnet having high magnetic properties and high relative density can be provided.
以下、本発明の実施形態を説明する。なお、本発明の実施態様は、後述する形態例に限定されるものではなく、その技術思想の範囲において、種々の変形が可能である。 Embodiments of the present invention will be described below. The embodiment of the present invention is not limited to the embodiments described later, and various modifications can be made within the scope of the technical idea.
本発明におけるＳｍ−Ｆｅ−Ｎ系希土類磁石は、Ｔｈ２Ｚｎ１７型結晶構造にＮが侵入したＳｍ２Ｆｅ１７Ｎ３相を主相とする。また、ＴｂＣｕ７型結晶構造相でもよい。また、Ｓｍ、Ｆｅ、Ｎの比率は化学両論比の２：１７：３に近い組成であれば、組成比がずれていても良い。 The Sm—Fe—N rare earth magnet in the present invention has a Sm 2 Fe 17 N 3 phase in which N penetrates into a Th 2 Zn 17 type crystal structure as a main phase. Further, it may be a TbCu 7 type crystal structure phase. Further, the composition ratio may be shifted as long as the ratio of Sm, Fe, and N is a composition close to the stoichiometric ratio of 2: 17: 3.
本発明での相対密度、つまり嵩密度は、焼結磁石の密度に対して主相の理論密度で除したものと定義され、焼結磁石の密度は、アルキメデス法によって測定されるものである。磁性粒子外の部分は、空隙であってもＺｎ等の低融点金属バインダー、その他の粒界成分であってもよい。相対密度を９０％以上とすることで、従来のボンド磁石を比較して、磁気特性がすぐれた磁石を得ることができる。 The relative density, that is, the bulk density in the present invention is defined as the density of the sintered magnet divided by the theoretical density of the main phase, and the density of the sintered magnet is measured by the Archimedes method. The portion outside the magnetic particles may be voids or a low melting point metal binder such as Zn, or other grain boundary components. By setting the relative density to 90% or more, it is possible to obtain a magnet having excellent magnetic characteristics as compared with a conventional bonded magnet.
本発明におけるＳｍ−Ｆｅ−Ｎ系希土類磁石は副相としてＳｍＦｅ３Ｎｘ相を含む。ＳｍＦｅ３Ｎｘ相は、主相のＳｍ２Ｆｅ１７Ｎ３相と比較して、酸化しやすい為、粉砕過程などで粒子表面に付着した酸素や炭化水素が焼成中に蒸発する際に、選択的にＳｍＦｅ３Ｎｘ相が酸化されることで、主相であるＳｍ２Ｆｅ１７Ｎ３相の酸化を防ぎ、磁気特性劣化を抑制することができる。なお、ＳｍＦｅ３Ｎｘ相は主として製造工程において主相の酸化を抑制する効果を担うが、焼結磁石になった後にも、外部から侵入する酸素や水分による主相の酸化を防ぐことができる。 The Sm—Fe—N rare earth magnet in the present invention includes an SmFe 3 N x phase as a subphase. The SmFe 3 N x phase is more easily oxidized than the main Sm 2 Fe 17 N 3 phase, so it is selected when oxygen and hydrocarbons adhering to the particle surface during the pulverization process evaporate during firing. In particular, the oxidation of the SmFe 3 N x phase can prevent oxidation of the Sm 2 Fe 17 N 3 phase, which is the main phase, and suppress deterioration of magnetic characteristics. The SmFe 3 N x phase is mainly responsible for suppressing the oxidation of the main phase in the manufacturing process, but can prevent oxidation of the main phase due to oxygen and moisture entering from the outside even after becoming a sintered magnet. .
また、副相として含むＳｍＦｅ３Ｎｘ相のｘは、１．０以上２．５以下である。ｘがこの範囲であるときに、ＳｍＦｅ３Ｎｘ相が安定して存在することができ、且つ、酸化抑制相としての機能を発揮することができる。 Moreover, x of the SmFe 3 N x phase included as a sub phase is 1.0 or more and 2.5 or less. When x is in this range, the SmFe 3 N x phase can exist stably and can function as an oxidation-inhibiting phase.
副相として含むＳｍＦｅ３Ｎｘ相は断面積の面積比率で５％以下（０を含まず）である。ＳｍＦｅ３Ｎｘ相は高い磁気特性を有さないことから、前記の範囲を超えることで、副相が磁気特性の低下要因となり、焼結磁石全体としての磁気特性が劣化する。 The SmFe 3 N x phase included as a subphase is 5% or less (excluding 0) in terms of the area ratio of the cross-sectional area. Since the SmFe 3 N x phase does not have high magnetic properties, the sub-phase causes a decrease in the magnetic properties by exceeding the above range, and the magnetic properties of the sintered magnet as a whole deteriorate.
副相として含むＳｍＦｅ３Ｎｘ相は、その一部が酸化していても良い。主相の酸化を抑制する機能を発揮した場合、その一部が酸化する。 A part of the SmFe 3 N x phase included as a sub phase may be oxidized. When the function of suppressing the oxidation of the main phase is exhibited, a part thereof is oxidized.
以下、本発明の磁石の製造方法の好適な例について説明する。 Hereinafter, a preferred example of the method for producing a magnet according to the present invention will be described.
以下、本発明の実施例および比較例を記述する。磁石の製造方法は、焼結法、急冷凝固法、蒸着法、ＨＤＤＲ法などあるが、急冷凝固法で得た合金を粉砕し、プラズマ焼結ＰＡＳ（通電固化）を用いて固化する方法を説明する。 Examples of the present invention and comparative examples will be described below. The magnet manufacturing method includes a sintering method, a rapid solidification method, a vapor deposition method, an HDDR method, etc., but an explanation is given of a method in which an alloy obtained by the rapid solidification method is pulverized and solidified using plasma sintering PAS (electrically solidified). To do.
まず、副相原料のＳｍＦｅ３Ｎｘ粉末を作製する。所望の組成比を有するＳｍ−Ｆｅ合金を準備する。原料合金は、Ｒ、Ｆｅそれぞれの原料を不活性ガス、望ましくはＡｒ雰囲気中でアーク溶解、その他公知の溶解法により作製することができる。 First, SmFe 3 N x powder as a secondary phase raw material is prepared. An Sm—Fe alloy having a desired composition ratio is prepared. The raw material alloy can be produced by arc melting of R and Fe raw materials in an inert gas, preferably in an Ar atmosphere, or other known melting methods.
上記方法で作製されたＳｍ−Ｆｅ合金を乳鉢で粉砕し、数十μｍ以下の粉体を作製する。乳鉢粉砕以外にも、スタンプミル、ジョークラッシャー、ブラウンミル等の粗粉砕機を用いて行うようにしてもよい。粉砕粉の結晶性が良好でない場合には、ここで結晶化処理として６００℃程度の熱処理を施してもよい。 次に、前記粉砕粉は窒化処理に供される。窒化処理は、窒化雰囲気中で、４５０〜５５０℃で２時間から１６時間の熱処理を行えばよく、窒素ガスの替わりにアンモニアガスとすることもでき、また水素ガスとの混合ガスでもよい。得られた窒化粉末をさらに平均粒径が数μｍになるように粉砕する。 The Sm—Fe alloy produced by the above method is pulverized in a mortar to produce a powder of several tens μm or less. In addition to mortar crushing, a coarse crusher such as a stamp mill, jaw crusher, or brown mill may be used. If the crystallinity of the pulverized powder is not good, a heat treatment at about 600 ° C. may be applied here as a crystallization treatment. Next, the pulverized powder is subjected to nitriding treatment. The nitriding treatment may be performed in a nitriding atmosphere at 450 to 550 ° C. for 2 to 16 hours, and ammonia gas may be used instead of nitrogen gas, or a mixed gas with hydrogen gas may be used. The obtained nitrided powder is further pulverized so that the average particle size becomes several μm.
主相とするＳｍ２Ｆｅ１７Ｎ３粉についても、適宜、合金配合組成を調整し、上記ＳｍＦｅ３Ｎｘ粉と同様に作製する。次に、Ｓｍ２Ｆｅ１７Ｎ３粉に対し、ＳｍＦｅ３Ｎｘ粉を所望の比率となるように配合し、混合粉末を作製した。さらに、焼結の助剤とするＺｎ粉末の適量を添加する。 The Sm 2 Fe 17 N 3 powder as the main phase is also prepared in the same manner as the SmFe 3 N x powder by appropriately adjusting the alloy composition. Next, SmFe 3 N x powder was blended at a desired ratio with respect to Sm 2 Fe 17 N 3 powder to prepare a mixed powder. Furthermore, an appropriate amount of Zn powder as a sintering aid is added.
得られた混合粉を超硬合金金型に充填し、真空雰囲気下で、プラズマ焼結ＰＡＳを行って焼結体を形成した。尚、この通電固化条件としては圧力：１０ｔｏｎ／ｃｍ２以上、昇温速度：２０℃／ｍｉｎ以上、焼結温度４００℃〜４８０℃、焼結時間１分以内とする。 The obtained mixed powder was filled in a cemented carbide mold and subjected to plasma sintering PAS in a vacuum atmosphere to form a sintered body. The current-solidifying conditions are pressure: 10 ton / cm 2 or more, heating rate: 20 ° C./min or more, sintering temperature of 400 ° C. to 480 ° C., and sintering time within 1 minute.
得られた焼結体を所望のサイズに加工した後、アルキメデス法によって密度を、振動試料型磁力計（ＶＳＭ：Ｖｉｂｒａｔｉｎｇ Ｓａｍｐｌｅ Ｍａｇｎｅｔｏｍｅｔｅｒ）によって磁気特性（残束磁束密度Ｂｒ、保磁力ＨｃＪ）を測定する。密度は理論値を（６．７６ｇ／ｃｍ３）とした場合の相対密度（％）を算出する。 After processing the obtained sintered body to a desired size, the density is measured by the Archimedes method, and the magnetic properties (residual flux density B r , coercive force H cJ ) are measured by a vibrating sample magnetometer (VSM). taking measurement. The density is calculated as a relative density (%) when the theoretical value is (6.76 g / cm 3 ).
また、焼結体の断面を走査透過電子顕微鏡（ＳＴＥＭ：Ｓｃａｎｎｉｎｇ Ｔｒａｎｓｍｉｓｓｉｏｎ Ｅｌｅｃｔｒｏｎ Ｍｉｃｒｏｓｃｏｐｅ）に備えられたエネルギー分散型Ｘ線分析（ＥＤＳ：Ｅｎｅｒｇｙ Ｄｉｓｐｅｒｓｉｖｅ Ｓｐｅｃｔｒｏｓｃｏｐｙ）装置にて観察し、ＳｍＦｅ３Ｎｘ相の有無、面積比率を評価する。元素マッピング像から、主相よりもＲリッチであり、Ｎを含有する領域を抽出し、さらに前記領域の中心付近の定量分析値において、ＳｍとＦｅとＮの原子数の比が、１：３：１．０〜２．５に近い場合に、前記領域がＳｍＦｅ３Ｎｘ相であると判別できる。ここで、５点以上のＳｍＦｅ３Ｎｘ相の定量分析値の平均を取ることで、ｘを決定する。また、ＳｍＦｅ３Ｎｘ相の領域を指定し、画像解析により面積を求めることで、単位面積あたりのＳｍＦｅ３Ｎｘ相の面積比率を算出する。ＳｍＦｅ３Ｎｘ相の酸化状態についても、ここで評価が可能である。 Further, a cross section of the sintered body was observed with an energy dispersive X-ray analysis (EDS) apparatus provided in a scanning transmission electron microscope (STEM), and the presence or absence of the SmFe 3 N x phase was observed. Evaluate the area ratio. From the element mapping image, a region that is R richer than the main phase and contains N is extracted, and in the quantitative analysis value near the center of the region, the ratio of the number of atoms of Sm, Fe, and N is 1: 3. : When it is close to 1.0 to 2.5, it can be determined that the region is the SmFe 3 N x phase. Here, x is determined by taking an average of quantitative analysis values of five or more SmFe 3 N x phases. Further, the area ratio of the SmFe 3 N x phase per unit area is calculated by designating the area of the SmFe 3 N x phase and obtaining the area by image analysis. The oxidation state of the SmFe 3 N x phase can also be evaluated here.
以下、本発明の内容を実施例及び比較例を用いて詳細に説明するが、本発明は以下の実施例に限定されるものではない。 Hereinafter, although the content of the present invention is explained in detail using an example and a comparative example, the present invention is not limited to the following examples.
＜実施例１＞
先ず、ＳｍメタルとＦｅメタルを１：３の割合で配合し、Ａｒで置換した真空溶解炉で溶解して合金化した。この合金の組成を分析したところ、ＳｍＦｅ３相が確認された。次に、合金を乳鉢で粉砕し、平均粒径３２μｍ以下の粉体を形成した。次に、この粉末をステンレスバットに入れ、これにＨ２を含んだＮ２ガスを流すと共に５００℃に加熱しながら１０時間窒化処理を行い、ＳｍＦｅ３Ｎｘ粉末を作製した。この窒化粉末をさらにボールミルで平均粒径１．７μｍに粉砕した。
<Example 1>
First, Sm metal and Fe metal were blended at a ratio of 1: 3, and melted and alloyed in a vacuum melting furnace substituted with Ar. Analysis of the composition of this alloy confirmed the SmFe 3 phase. Next, the alloy was pulverized in a mortar to form a powder having an average particle size of 32 μm or less. Next, this powder was put into a stainless steel vat, and N 2 gas containing H 2 was allowed to flow through it, and nitriding was performed for 10 hours while heating to 500 ° C. to produce SmFe 3 N x powder. This nitrided powder was further pulverized by a ball mill to an average particle size of 1.7 μm.
また、主相とするＳｍ２Ｆｅ１７Ｎ３粉についても、適宜、合金配合組成を調整し、上記ＳｍＦｅ３Ｎｘ粉と同様に作製した。得られた粉末は、ＸＲＤにてＳｍ２Ｆｅ１７Ｎ３相の単相であることを確認した。平均粒径は、１．１μｍであった。 As for the Sm 2 Fe 17 N 3 powder as a main phase, appropriately, by adjusting the alloy blend composition was prepared in the same manner as described above SmFe 3 N x powder. It was confirmed by XRD that the obtained powder was a single phase of Sm 2 Fe 17 N 3 phase. The average particle size was 1.1 μm.
Ｓｍ２Ｆｅ１７Ｎ３粉に対し、ＳｍＦｅ３Ｎｘ粉を断面の面積比率で約５％となるよう配合し、混合粉末を作製した。さらに、Ｚｎ粉末を５重量％添加した。 SmFe 3 N x powder was blended with the Sm 2 Fe 17 N 3 powder so that the cross-sectional area ratio was about 5% to prepare a mixed powder. Further, 5% by weight of Zn powder was added.
得られた混合粉２ｇを１０φの超硬合金金型に充填し、真空雰囲気下で、プラズマ焼結ＰＡＳを行って２つの固形体を形成した。尚、この通電固化条件としては圧力：１２ｔｏｎ／ｃｍ２、昇温速度：５０℃／ｍｉｎ、焼結温度４５０℃、焼結時間１分にて焼結を行った。 2 g of the obtained mixed powder was filled in a 10φ cemented carbide alloy mold and subjected to plasma sintering PAS in a vacuum atmosphere to form two solid bodies. In addition, as this electric current solidification condition, it sintered by pressure: 12ton / cm < 2 >, temperature rising rate: 50 degreeC / min, sintering temperature 450 degreeC, and sintering time 1 minute.
得られた焼結体の相対密度、磁気特性を測定した。また、焼結体の断面観察を行い、ＳｍＦｅ３Ｎｘ相のｘの値、面積比率について評価した。その結果を表１に示す。 The relative density and magnetic properties of the obtained sintered body were measured. Also, performing sectional observation of the sintered body, the value of SmFe 3 N x phase x, were evaluated for the area ratio. The results are shown in Table 1.
＜比較例１＞
ＳｍＦｅ３Ｎｘ粉を添加しなかった他は、実施例１と同様に焼結体を作製し、評価を行った。結果を表１に示す。
<Comparative Example 1>
A sintered body was prepared and evaluated in the same manner as in Example 1 except that the SmFe 3 N x powder was not added. The results are shown in Table 1.
＜実施例２、比較例３、比較例２＞
ＳｍＦｅ３Ｎｘ粉の添加量を、面積比率で０．１％、１％、１０％となるようにした他は、実施例１と同様に焼結体を作製し、評価を行った。結果を表１に示す。
<Example 2, Comparative Example 3, Comparative Example 2>
A sintered body was produced and evaluated in the same manner as in Example 1 except that the amount of SmFe 3 N x powder added was 0.1%, 1%, and 10% in terms of area ratio. The results are shown in Table 1.
＜比較例３、実施例４、実施例５＞
ＳｍＦｅ３Ｎｘ粉の作製時における窒化処理時間を１時間、３時間、１５時間とした他は、実施例１と同様に焼結体を作製し、評価を行った。結果を表１に示す。
<Comparative Example 3, Example 4, Example 5>
A sintered body was produced and evaluated in the same manner as in Example 1 except that the nitriding treatment time in producing the SmFe 3 N x powder was 1 hour, 3 hours, and 15 hours. The results are shown in Table 1.
＜実施例６＞
通電固化条件として、昇温速度：１０００℃／ｍｉｎ、焼結時間０分に変更して焼結を行ったほかは、実施例１と同様に焼結体を作製し、評価を行った結果を表１に示す。
<Example 6>
As the current-carrying solidification conditions, except that the heating rate was changed to 1000 ° C./min and the sintering time was changed to 0 minutes, the sintered body was produced in the same manner as in Example 1, and the evaluation results were obtained. Table 1 shows.
＜比較例４＞
通電固化条件として、焼結温度を３５０℃に変更して焼結を行ったほかは、実施例１と同様に焼結体を作製し、評価を行った結果を表１に示す
<Comparative example 4>
Table 1 shows the results of producing and evaluating the sintered body in the same manner as in Example 1 except that the sintering was performed by changing the sintering temperature to 350 ° C. as the electric current solidifying condition.
表１より、ＳｍＦｅ３Ｎｘ相を断面積の面積比率で０．１％から５％存在させることで、ＳｍＦｅ３Ｎｘ相を添加しなかった比較例１と比較して、保磁力ＨｃＪの向上が見られた。これらの焼結体中のＳｍＦｅ３Ｎｘ相の多くは酸化しており、また、ＳｍＦｅ３Ｎｘ相を添加しなかった比較例１の主相粒子は、実施例の主相粒子よりも酸化している領域が多かったことから、ＳｍＦｅ３Ｎｘ相は主相の酸化抑制相として機能したことが推察される。ただし、実施例の焼結体中のＳｍＦｅ３Ｎｘ相の一部には酸化していない領域もあった。また、比較例２のように、ＳｍＦｅ３Ｎｘ相が多く存在した場合は、残留磁化Ｂｒおよび保磁力ＨｃＪの低下が見られた。添加したＳｍＦｅ３Ｎｘ相自体が特性の低下要因となったものと考えられる。さらに、ＳｍＦｅ３Ｎｘ相のｘが小さい場合には、保磁力が低下した。この焼結体のＳｍＦｅ３Ｎｘ相近傍には、α−Ｆｅが散見され、ＳｍＦｅ３Ｎｘ相の分解によって生成した軟磁性相が磁気特性劣化の要因になったと推察される。一方、相対密度が低い場合には、ＳｍＦｅ３Ｎｘ相の状態によらず、磁気特性が低いことがわかった。 From Table 1, the presence 5% 0.1% SmFe 3 N x phase in area ratio of the cross-sectional area, as compared with Comparative Example 1 was not added SmFe 3 N x phase, the coercivity H cJ Improvement was seen. Most of the SmFe 3 N x phases in these sintered bodies are oxidized, and the main phase particles of Comparative Example 1 to which no SmFe 3 N x phase is added are oxidized more than the main phase particles of the examples. From the fact that there were many regions, it is assumed that the SmFe 3 N x phase functioned as an oxidation-suppressing phase of the main phase. However, some of the SmFe 3 N x phases in the sintered bodies of the examples were not oxidized. Also, as in Comparative Example 2, if there are many SmFe 3 N x phase, decrease in remanence B r and coercivity H cJ was observed. It is considered that the added SmFe 3 N x phase itself was a cause of deterioration in characteristics. Furthermore, when x of the SmFe 3 N x phase was small, the coercive force was lowered. In the vicinity of the SmFe 3 N x phase of this sintered body, α-Fe is scattered, and it is presumed that the soft magnetic phase generated by the decomposition of the SmFe 3 N x phase has caused the deterioration of the magnetic properties. On the other hand, it was found that when the relative density is low, the magnetic properties are low regardless of the state of the SmFe 3 N x phase.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2015083005A JP6520337B2 (en) | 2015-04-15 | 2015-04-15 | Sm-Fe-N rare earth magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2015083005A JP6520337B2 (en) | 2015-04-15 | 2015-04-15 | Sm-Fe-N rare earth magnet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2016207677A true JP2016207677A (en) | 2016-12-08 |
| JP6520337B2 JP6520337B2 (en) | 2019-05-29 |
Family
ID=57490185
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2015083005A Active JP6520337B2 (en) | 2015-04-15 | 2015-04-15 | Sm-Fe-N rare earth magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6520337B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108777204A (en) * | 2018-05-08 | 2018-11-09 | 华南理工大学 | A kind of preparation method of samarium iron nitrogen permanent-magnet powder |
| JP2021052111A (en) * | 2019-09-25 | 2021-04-01 | トヨタ自動車株式会社 | Method for manufacturing rare earth magnet |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05166614A (en) * | 1991-12-19 | 1993-07-02 | Tdk Corp | Production of magnet and mother alloy for it |
| JPH05320831A (en) * | 1992-05-21 | 1993-12-07 | Asahi Chem Ind Co Ltd | Alloy for permanent magnet |
| JPH07240307A (en) * | 1994-02-28 | 1995-09-12 | Isuzu Motors Ltd | Nitrogen-bearing rare-earth permanent magnet and its manufacture |
| JP2002270416A (en) * | 2001-03-14 | 2002-09-20 | Shin Etsu Chem Co Ltd | Bulk anisotropic rare earth permanent magnet and its manufacturing method |
-
2015
- 2015-04-15 JP JP2015083005A patent/JP6520337B2/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05166614A (en) * | 1991-12-19 | 1993-07-02 | Tdk Corp | Production of magnet and mother alloy for it |
| JPH05320831A (en) * | 1992-05-21 | 1993-12-07 | Asahi Chem Ind Co Ltd | Alloy for permanent magnet |
| JPH07240307A (en) * | 1994-02-28 | 1995-09-12 | Isuzu Motors Ltd | Nitrogen-bearing rare-earth permanent magnet and its manufacture |
| JP2002270416A (en) * | 2001-03-14 | 2002-09-20 | Shin Etsu Chem Co Ltd | Bulk anisotropic rare earth permanent magnet and its manufacturing method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108777204A (en) * | 2018-05-08 | 2018-11-09 | 华南理工大学 | A kind of preparation method of samarium iron nitrogen permanent-magnet powder |
| JP2021052111A (en) * | 2019-09-25 | 2021-04-01 | トヨタ自動車株式会社 | Method for manufacturing rare earth magnet |
| JP7156226B2 (en) | 2019-09-25 | 2022-10-19 | トヨタ自動車株式会社 | Method for manufacturing rare earth magnet |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6520337B2 (en) | 2019-05-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6094612B2 (en) | Method for producing RTB-based sintered magnet | |
| JP6693392B2 (en) | R- (Fe, Co) -B system sintered magnet and its manufacturing method | |
| JP2004165482A (en) | R-Fe-B SYSTEM SINTERED MAGNET | |
| JPH0521218A (en) | Production of rare-earth permanent magnet | |
| WO2005001856A1 (en) | R-t-b based rare earth permanent magnet and method for production thereof | |
| JP4314244B2 (en) | Magnetic material powder manufacturing method and bonded magnet manufacturing method | |
| JPWO2004029996A1 (en) | R-T-B rare earth permanent magnet | |
| JP2000114017A (en) | Permanent magnet and material thereof | |
| JP7315888B2 (en) | RTB permanent magnet and manufacturing method thereof | |
| JP4900085B2 (en) | Rare earth magnet manufacturing method | |
| JP2024020341A (en) | Anisotropic rare earth sintered magnet and method for manufacturing the same | |
| JP2016207677A (en) | Sm-Fe-N BASED RARE EARTH MAGNET | |
| CN109671547A (en) | R-T-B based sintered magnet and its manufacturing method | |
| JP6706571B2 (en) | Rare earth cobalt-based permanent magnet for ignition coil and manufacturing method thereof | |
| JP2002294413A (en) | Magnet material and manufacturing method therefor | |
| JP2000114016A (en) | Permanent magnet and manufacture thereof | |
| JP6465448B2 (en) | Magnet raw material mainly composed of Sm-Fe binary alloy, method for producing the same, and magnet | |
| JP2020155740A (en) | Method for producing rare earth magnet | |
| JP4260087B2 (en) | Rare earth sintered magnet and manufacturing method thereof | |
| CN108389674A (en) | R-T-B systems sintered magnet | |
| JP2001123201A (en) | Method for producing sinetred permanent magnet | |
| JP3073807B2 (en) | Iron-rare earth permanent magnet material and method for producing the same | |
| JP2006213984A (en) | Super-magnetostrictive material and manufacturing method therefor | |
| JP7256483B2 (en) | RTB permanent magnet and manufacturing method thereof | |
| JP7495376B2 (en) | Anisotropic rare earth sintered magnet and its manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20171120 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20181031 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20181113 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20190110 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20190402 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20190415 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6520337 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |