JPS61264157A - Material for permanent magnet - Google Patents

Abstract

PURPOSE:To prevent deterioration in magnetic characteristics attendant upon the grinding work of a sintered magnetic body by forming a vapor deposition phase consisting of body-centered cubic phase mainly composed of Nd on the surface, to be ground, of Fe-B-rare earth element-type thin permanent magnet material having a specific composition. CONSTITUTION:The sintered magnet body having a composition mainly composed of, by atom, 10-30% R (>=1 element among Nd, Pr, Dy, Ho, Tb, or further, La, Ce, Sm, Gd, Er, Eu, Tm, Yb, La and Y), 2-28% B, and 65-80% Fe is formed, which has a main phase consisting of tetragonal cubic phase and is <=2.5cm<3> in volume or <=5.0mm in thickness. The vapor deposition layer of rare earth element mainly composed of Nd is formed by adhesion on the surface, to be ground, of the above sintered magnet body, which is subjected to two-stage aging treatment to allow the vapor deposition layer consisting of body-centered cubic phase to adhere to the above. In this way, the crystal groups in the primary worked surface layer are provided with coercive force, so that deterioration in magnetic properties caused by grinding work can be prevented.

Description

【発明の詳細な説明】 利用産業分野 この発明は、焼結永久磁石表面の研削加工等に伴なう磁
石特性の劣化を防止したＦａ−Ｂ−Ｒ系永久磁石に係り
、特に、体積が２．５ｃｎ？以下あるいは厚みが５．０
ｍｍ以下の小物あるいは薄物用永久磁石材料に関する。Detailed Description of the Invention Field of Application This invention relates to an Fa-BR permanent magnet that prevents deterioration of magnetic properties due to grinding of the surface of a sintered permanent magnet. .5cn? Less than or equal to 5.0 thick
It relates to permanent magnet materials for small or thin objects of mm or less.

背景技術 現在の代表的な永久磁石材料は、アルニコ、ハードフェ
ライトおよび希土類コバルト磁石でおる。BACKGROUND ART Current typical permanent magnet materials include alnico, hard ferrite, and rare earth cobalt magnets.

この希土類コバルト磁石は、磁気特性が格段にすぐれて
いるため、多種用途に利用されているが、主成分のＳｍ
、Ｃｏは共に資源的に不足し、かつ高価であり、今後長
期間にわたって、安定して多量に供給されることは困難
でおる。This rare earth cobalt magnet has extremely excellent magnetic properties and is used for a variety of purposes, but the main component is S.
, Co are both in short supply and expensive, and it will be difficult to stably supply them in large quantities for a long period of time.

そのため、磁気特性がすぐれ、かつ安価で、さらに資源
的に豊富で今後の安定供給が可能な組成元素からなる永
久磁石材料が切望されてきた。Therefore, there has been a strong desire for a permanent magnet material that has excellent magnetic properties, is inexpensive, and is composed of constituent elements that are abundant in resources and can be stably supplied in the future.

本出願人は先に、高価な論やらを含有しない新しい高性
能永久１石としてＦｅ−Ｂ−Ｒ系（ＲはＹを含む希土類
元素のうち少なくとも１種）永久磁石を提案した（特開
昭５９−４６００８号、特開昭５９−６４７３３号、特
開昭５９−８９４０１号、特開昭５９−１３２１０４号
）。The present applicant previously proposed a Fe-BR-based permanent magnet (R is at least one rare earth element including Y) as a new high-performance permanent magnet that does not contain expensive materials (Japanese Patent Application Laid-Open No. 59-46008, JP-A-59-64733, JP-A-59-89401, JP-A-59-132104).

この永久磁石は、Ｒとして陶や円を中心とする資源的に
豊富な軽希土類を用い、Ｆｅを主成分として２５ＭＧＯ
ａ以上の極めて高いエネルギー積を示す、すぐれた永久
！ａ石である。This permanent magnet uses resource-rich light rare earth materials such as ceramics and circles as R, and uses 25MGO with Fe as the main component.
Excellent permanent, showing an extremely high energy product of more than a! It is a stone.

最近、磁気回路の高性能化、小形化に伴ない、Ｆｓ−Ｂ
−Ｒ系永久磁石材料が益々注目され、さらに、体積が２
．５ｃＪ１？以下あるいは厚みが５．０ｍｍ以下の小物
おるいは薄物用Ｆθ−Ｂ−Ｒ系永久磁石材料が要望され
てきた。Recently, with the improvement in performance and miniaturization of magnetic circuits, Fs-B
-R-based permanent magnet materials are attracting more and more attention, and the volume is 2
．． 5cJ1? There has been a demand for Fθ-BR-based permanent magnet materials for small or thin items with a thickness of 5.0 mm or less.

かかる用途の永久磁石材料を製造するには、成形焼結し
た小物あるいは極薄物の焼結磁石体は、その表面の凹凸
や歪みを除去するため、あるいは表面酸化層を除去する
ため、さらには磁気回路に組込むために、磁石体の全面
あるいは所要表面を切削加工する必要がおり、加工には
外周刃切断機。In order to manufacture permanent magnet materials for such uses, small or ultra-thin sintered magnets must be processed to remove surface irregularities and distortions, or to remove surface oxidation layers, and to remove magnetic In order to incorporate it into the circuit, it is necessary to cut the entire surface or the required surface of the magnet, and a peripheral blade cutting machine is used for the processing.

内周刃切断機２表面研削機、センタレスグラインダー、
ラッピングマシン等が使用される。Internal blade cutting machine 2 surface grinding machine, centerless grinder,
A wrapping machine etc. are used.

しかしながら、上記製画にてＦｅ−Ｂ−Ｒ系永久磁石材
料を研削加工すると、例えば、厚み２０ｍｍより１ｍｍ
〜１０ｍｍ製品厚みに加工すると、第２図の曲線すに示
す如く、各磁気特性が劣化する問題があった。However, when grinding the Fe-B-R permanent magnet material in the above drawing, for example, the thickness is 1 mm from 20 mm.
When processed to a product thickness of ~10 mm, there was a problem that various magnetic properties deteriorated, as shown by the curves in FIG.

発明の目的 この発明は、希土類・ボロン・鉄を主成分とする新規な
永久磁石材料において、特に小物あるいは極薄物用の焼
結磁石体の切削加工に伴なう磁気特性の劣化を防止した
永久磁石材料を目的としている。Purpose of the Invention This invention is a new permanent magnet material mainly composed of rare earth elements, boron, and iron, which prevents the deterioration of magnetic properties caused by cutting of sintered magnet bodies for small or ultra-thin objects. Intended for magnetic materials.

発明の構成と効果 発明者らは、ＦＥＩ−Ｂ−Ｒ系永久ｖｉｉ石材料の保磁
力について種々検討した結果、前記磁石体の保磁力の大
小は、結晶粒内よりも粒界構造の差異に基因しており、
研摩された焼結磁石表面を、Ｋｅｒｒ効果を用いた光学
顕微鏡で、磁区の反転＠横を詳細に調べると、磁石体表
面の磁化反転が磁石体内部の保磁力の１７２以下の非常
に低い磁界で起り、焼結磁石体の加工された表面第１層
の結晶群の保磁力が低い理由は、高保磁力を出現するた
めに必要な最適の体心立方相が存在しないためでおるこ
とを知見した。Structure and effect of the invention As a result of various studies on the coercive force of the FEI-B-R permanent stone material, the inventors found that the magnitude of the coercive force of the magnet body is due to differences in the grain boundary structure rather than within the crystal grains. It is the underlying cause,
When the surface of a polished sintered magnet is examined in detail for magnetic domain reversal @ lateral using an optical microscope using the Kerr effect, it is found that the magnetization reversal on the magnet surface occurs in a very low magnetic field below the coercive force of 172 inside the magnet. It was discovered that the reason why the coercive force of the crystal group in the first layer on the processed surface of the sintered magnet body is low is because the optimal body-centered cubic phase necessary for the appearance of high coercive force does not exist. did.

発明者が始めて発見した高保磁力を出現させる体心立方
相を、加工された焼結磁石体表面の結晶群上に、最適の
厚みでかつ特殊な体心立方相構造を有する粒界相として
設けることは、通常の方法では容易ではないが、厚み１
証以下のＮｄを主成分とする体心立方相の蒸着層を形成
することにより、Ｆｅ−Ｂ−Ｒ系永久磁石材料の保磁力
並びに減磁曲線の角型性を改善向上させ得ることを知見
し、この発明を完成したものでおる。The body-centered cubic phase that exhibits high coercive force, which was first discovered by the inventor, is provided as a grain boundary phase with an optimal thickness and a special body-centered cubic phase structure on the crystal group on the surface of the processed sintered magnet. This is not easy to do using normal methods, but if the thickness is 1
It was discovered that the coercive force and squareness of the demagnetization curve of Fe-B-R permanent magnet materials can be improved by forming a body-centered cubic phase vapor deposited layer containing Nd as the main component. However, this invention has been completed.

すなわち、この発明は、 Ｒ（ＲはＮｄ、　Ｐｒ、　Ｄｙ、　Ｈｏ、　Ｔｂのうち
少なくとも１種あるいはざらに、Ｌａ、　Ｃ８，Ｓｍ、
　Ｃｄ、　Ｅｒ、　Ｅｕ、丁ｍ。That is, this invention provides R (R is at least one of Nd, Pr, Dy, Ho, Tb, or in general, La, C8, Sm,
Cd, Er, Eu, Dingm.

Ｙｂ、　Ｌａ、　Ｙのうち少なくとも１種からなる）１
０％〜３０原子％、 Ｂ２原子％〜２８原子％、 Ｆｅ６５原子％〜８０原子％を主成分とし、主相が正方
晶相からなる体積が２．５ａｊ以下あるいは厚みが５．
０ｍｍ以下の焼結磁石体の被研削加工面に、Ｎｄを主成
分とする体心立方相からなる蒸着層を有することを特徴
する永久磁石材料である。consisting of at least one of Yb, La, Y)1
The main components are 0% to 30 atomic%, B2 atomic% to 28 atomic%, and Fe65 atomic% to 80 atomic%, and the main phase is a tetragonal phase, and the volume is 2.5aj or less or the thickness is 5.
This permanent magnet material is characterized by having a deposited layer of a body-centered cubic phase containing Nd as a main component on the ground surface of a sintered magnet body of 0 mm or less.

ざらに詳述すれば、上記の焼結磁石体の被研削加工面に
、陶あるいはＮｄを主成分とし、残部はＮｄを除きＹを
含む希土類元素のうち少なくとも１種からなる蒸着層を
被着形成後、７００℃〜ｉ　ｏｏｏ℃及び６５０℃〜４
５０℃の２段の時効処理を施して、体心立方相からなる
蒸着層を被着させ、該加工表面第１層の結晶群に保磁力
を付与し、研削加工による磁気特性の劣化を防止したこ
とを特徴する永久磁石材料である。More specifically, on the surface to be ground of the sintered magnet body described above, a vapor deposited layer is deposited on the surface to be ground of the above-mentioned sintered magnet body, the main component being ceramic or Nd, and the remainder being at least one rare earth element including Y, excluding Nd. After formation, 700°C to i ooo°C and 650°C to 4
A two-stage aging treatment at 50°C is applied to deposit a deposited layer consisting of a body-centered cubic phase, which imparts coercive force to the crystal group of the first layer on the processed surface and prevents deterioration of magnetic properties due to grinding. It is a permanent magnetic material with the following characteristics.

また、この発明の永久磁石材料は平均結晶粒径が１〜８
０加の範囲にある正方品系の結晶構造を有する化合物を
主相とし、体積比で１％〜５０％の非磁性相（酸化物相
を除く）を含むことを特徴とする。Further, the permanent magnet material of this invention has an average crystal grain size of 1 to 8.
It is characterized by having a compound having a tetragonal crystal structure in the range of 0 as the main phase, and containing a nonmagnetic phase (excluding the oxide phase) in a volume ratio of 1% to 50%.

したがって、この発明の永久磁石材料は、Ｒとして陶あ
るいはざらに門を中心とする資源的に豊富な軽希土類を
主に用い、Ｆｅ、Ｂ、Ｒ，を主成分とすることにより、
２５ＭＧＯ，以上の極めて高いエネルギー積並びに、高
残留磁束密度、高保磁力を有し、かつ研削加工による磁
気特性の劣化を防止したＦｅ　−Ｂ　−Ｒ系永久磁石材
料を安価に得ることができる。Therefore, the permanent magnet material of the present invention mainly uses light rare earths, which are rich in resources such as ceramics or zaranimon, as R, and has Fe, B, and R as the main components.
A Fe-B-R permanent magnet material having an extremely high energy product of 25 MGO or more, high residual magnetic flux density, and high coercive force, and preventing deterioration of magnetic properties due to grinding can be obtained at a low cost.

この発明において、焼結磁石体の被研削加工表面に、Ｎ
ｄを主成分とする体心立方相の蒸着層を被着させるには
、真空蒸着、スパッタリング等の薄膜形成方法が適宜選
定利用できる。また、蒸着層の厚みは、１ｍを越えると
該蒸着層の剥離あるいは機械的強度の低下を招来し、か
つ体心立方相を形成しないため好ましくなく、１ρ以下
の厚みとし、最も好ましくは０．５項以下の層厚みであ
る。In this invention, N is added to the surface of the sintered magnet body to be ground.
In order to deposit a body-centered cubic phase vapor deposition layer containing d as a main component, thin film forming methods such as vacuum vapor deposition and sputtering can be appropriately selected and utilized. Further, if the thickness of the vapor deposited layer exceeds 1 m, it is not preferable because it may cause peeling of the vapor deposited layer or decrease in mechanical strength, and it will not form a body-centered cubic phase. The layer thickness is 5 terms or less.

永久磁石の成分限定理由 この発明の永久磁石に用いる希土類元素Ｒは、組成の１
０原子％〜３０原子％を占めるが、ｍ、　Ｐｒ。Reason for limiting the composition of permanent magnet The rare earth element R used in the permanent magnet of this invention has a composition of 1
occupies 0 atomic % to 30 atomic %, m, Pr.

き、）ｔｏ、Ｔｂのうち少なくとも１種、あるいはさら
に、Ｌａ、　Ｃｅ、　Ｓｍ、　Ｃｔｒ、　Ｅｒ、　Ｅｕ
、　Ｔｍ、　Ｙｂ、ム、Ｙのうち少なくとも１種を含む
ものが好ましい。)to, at least one of Tb, or in addition, La, Ce, Sm, Ctr, Er, Eu
, Tm, Yb, M, and Y are preferred.

また、通常Ｒのうち１種をもって足りるが、実用上は２
種以上の混合物（ミツシュメタル、ジジム等）を入手上
の便宜等の理由により用いることができる。Also, normally one type of R is sufficient, but in practice two types are sufficient.
A mixture of more than one species (Mitushmetal, Didim, etc.) can be used for reasons such as availability.

なお、このＲは純希土類元素でなくてもよく、工業上入
手可能な範囲で製造上不可避な不純物を含有するもので
も差支えない。Note that this R does not have to be a pure rare earth element, and may contain impurities that are unavoidable in production within an industrially available range.

Ｒは、新規な上記系永久磁石材料における、必須元素で
あって、１０原子％未満では、結晶構造がα−鉄と同一
構造の立方晶組織となるため、高磁気特性、特に高保磁
力が得られず、３０原子％を越えると、Ｒリッチな非磁
性相が多くなり、残留磁束密度（Ｓｒ）が低下して、す
ぐれた特性の永久磁石が得られない。よって、希土類元
素は、１０原子％〜３０原子％の範囲とする。R is an essential element in the new above-mentioned permanent magnet material, and if it is less than 10 atomic %, the crystal structure becomes a cubic structure that is the same as α-iron, so high magnetic properties, especially high coercive force, can be obtained. If it exceeds 30 atomic %, the R-rich nonmagnetic phase increases, the residual magnetic flux density (Sr) decreases, and a permanent magnet with excellent characteristics cannot be obtained. Therefore, the rare earth element is in the range of 10 atomic % to 30 atomic %.

Ｂは、この発明による永久磁石材料における、必須元素
であって、２原子％未満では、菱面体構造が主相となり
、高い保磁力（ｉＨＣ）は得られず、２８原子％を越え
ると、Ｂリッチな非磁性相が多くなり、残留磁束密度（
Ｂｒ）が低下するため、すぐれた永久磁石が得られない
。よって、Ｂは、２原子％〜２８原子％の範囲とする。B is an essential element in the permanent magnet material according to the present invention, and if it is less than 2 atomic %, the rhombohedral structure becomes the main phase and high coercive force (iHC) cannot be obtained, and if it exceeds 28 atomic %, B The rich nonmagnetic phase increases, and the residual magnetic flux density (
Br) decreases, making it impossible to obtain an excellent permanent magnet. Therefore, B is in the range of 2 atomic % to 28 atomic %.

Ｆｅは、新規な上記系永久磁石において、必須元素であ
り、６５原子％未満では残留磁束密度（Ｓｒ）が低下し
、８０原子％を越えると、高い保磁力が得られないので
、Ｆｅは６５原子％〜８０原子％の含有とする。Fe is an essential element in the new above-mentioned permanent magnet.If it is less than 65 at%, the residual magnetic flux density (Sr) decreases, and if it exceeds 80 at%, high coercive force cannot be obtained. The content is from atomic % to 80 atomic %.

また、この発明による永久磁石材料において、ＦＢの一
部を巳で置換することは、得られる磁石の磁気特性を損
うことなく、温度特性を改善することができるが、Ｇ置
換量がＦａの２０％を越えると、逆に磁気特性が劣化す
るため、好ましくない。■の置換量がＦＢと６の合計量
で５原子％〜１５原子％の場合は、（Ｓｒ）は置換しな
い場合に比較して増加するため、高磁束密度を得るため
には好ましい。In addition, in the permanent magnet material according to the present invention, replacing a part of FB with Sn can improve the temperature characteristics without impairing the magnetic properties of the resulting magnet, but the amount of G substitution is smaller than that of Fa. If it exceeds 20%, the magnetic properties will deteriorate, which is not preferable. When the amount of substitution (2) is 5 to 15 atom % in the total amount of FB and 6, (Sr) increases compared to the case where no substitution is made, which is preferable in order to obtain a high magnetic flux density.

また、この発明による永久磁石は、Ｒ，Ｂ、Ｆｅの他、
工業的生産上不可避的不純物の存在を許容できるが、Ｂ
の一部を４．０原子％以下のＣ，３，５原子％以下のＰ
、２．５原子％以下のＳ、３．５原子％以下のへのうち
少なくとも１種、合計量で４．０原子％以下で置換する
ことにより、永久磁石の製造性改善、低価格化が可能で
ある。In addition to R, B, and Fe, the permanent magnet according to the present invention also includes
Although the presence of unavoidable impurities in industrial production can be tolerated, B
4.0 atomic% or less of C, 3.5 atomic% or less of P
, 2.5 at% or less of S, 3.5 at% or less of It is possible.

また、下記添加元素のうち少なくとも１種は、ＲＢ　　
Ｆａ系永久磁石に対してその保磁力、減磁曲線の角型性
を改善あるいは製造性の改善、低価格化に効果があるた
め添加することができる。しかし、保磁力改善のための
添加に伴ない残留磁束密度（Ｂｒ）の低下を招来するの
で、従来のハードフェライト磁石の残留磁束密度と同等
以上となる範囲での添加が望ましい。In addition, at least one of the following additional elements is RB
It can be added to Fa-based permanent magnets because it is effective in improving the coercive force and squareness of the demagnetization curve, improving manufacturability, and reducing costs. However, addition to improve coercive force causes a decrease in residual magnetic flux density (Br), so it is desirable to add in a range that is equal to or higher than the residual magnetic flux density of conventional hard ferrite magnets.

９．５原子％以下のＡ１．４．５原子％以下のＴｉ、９
．５原子％以下のＶ、８．５原子％以下のＣｒ。A1 of 9.5 atom% or less; Ti of 4.5 atom% or less, 9
．． V at 5 atomic % or less, Cr at 8.5 atomic % or less.

８．０原子％以下のＨｎ、５．０原子％以下のＢｉ、９
．５原子％以下のＮｂ、９．５原子％以下の丁ａ、９．
５原子％以下の）ＩＱ、　　９．５原子％以下のり、２
．５原子％以下のｓｂ、１原子％以下の６０．３．５原
子％以下のＳｎ、　　５．５原子％以下のＺｒ。Hn of 8.0 atom% or less, Bi of 5.0 atom% or less, 9
．． 5 at % or less Nb, 9.5 at % or less Ding a, 9.
5 at% or less) IQ, 9.5 at% or less glue, 2
．． 5 at % or less sb, 1 at % or less 60.3.5 at % or less Sn, 5.5 at % or less Zr.

９．０原子％以下のＮｉ、　　９．０原子％以下の５ｉ
１１．１原子％以下のｚｎ、５．５原子％以下のＨｆ。9.0 at% or less Ni, 9.0 at% or less 5i
Zn of 11.1 atomic % or less, Hf of 5.5 atomic % or less.

のうち少なくとも１種を添加含有、但し、２種以上含有
する場合は、その最大含有量は当該添加元素のうち最大
値を有するものの原子％以下の含有させることにより、
永久磁石の高保磁力化が可能になる。At least one of these elements is added and contained; however, when two or more types are contained, the maximum content is less than or equal to the atomic percent of the element having the maximum value among the added elements.
It becomes possible to increase the coercive force of permanent magnets.

結晶相は主相が正方品であることが、微細で均一な合金
粉末より、すぐれた磁気特性を有する焼結永久磁石を作
製するのに不可欠でおる。It is essential that the main phase of the crystalline phase be tetragonal in order to produce a sintered permanent magnet having superior magnetic properties than a fine and uniform alloy powder.

また、この発明の永久磁石は、磁場中プレス成型するこ
とにより磁気的異方性磁石が得られ、また、無磁界中で
プレス成型することにより、磁気的等方性磁石を得るこ
とができる。Further, the permanent magnet of the present invention can be press-molded in a magnetic field to obtain a magnetically anisotropic magnet, and can be press-molded in a non-magnetic field to obtain a magnetically isotropic magnet.

この発明による永久磁石は、 保磁力ｉＨｃ≧１　ｋＯａ、残留磁束密度Ｂｒ＞　４ｋ
Ｇ、を示し、最大エネルギー積（ＢＨ）ｍａｘは、最も
好ましい組成範囲では、（ＢＨ）ｍａＸ≧１０８ＧＯａ
を示し、最大値は２５）ＩＧＯθ以上に達する。The permanent magnet according to the present invention has a coercive force iHc≧1 kOa and a residual magnetic flux density Br>4k.
G, and the maximum energy product (BH)max is (BH)max≧108GOa in the most preferable composition range.
The maximum value reaches 25) IGOθ or more.

また、この発明永久磁石用合金粉末のＲの主成分がその
５０％以上を陶及び円を主とする軽希土類金属が占める
場合で、Ｒ１２原子％〜２０原子％、Ｂ４原子％〜２４
原子％、Ｆ８７４原子％〜８０原子％、を主成分とする
とき、（ＢＨ）ｍａｘ　３５ＨＧＯｅ以上のすぐれた磁
気特性を示し、特に軽希土類金属が陶の場合には、その
最大値が４２）ＩＧＯｓ以上に達する。In addition, in the case where the main component of R in the alloy powder for permanent magnets of this invention is light rare earth metals mainly composed of ceramic and yen, R12 atomic % to 20 atomic % and B4 atomic % to 24 atomic %.
When the main component is (BH)max 35HGOe or more, especially when the light rare earth metal is ceramic, the maximum value is 42) IGOs. reach more than that.

実施例 実■北ロー 出発原料として、純度９９゜９％の電解鉄、フェロボロ
ン合金、純度９９．７％以上のＮｄを使用し、これらを
配合後高周波溶解し、その後水冷銅鋳型に鋳造し、１５
．５Ｎｄ　７．５　Ｂ　７７Ｆｅなる組成の鋳塊を得た
。Example ■ As starting materials for Northern Row, electrolytic iron with a purity of 99.9%, ferroboron alloy, and Nd with a purity of 99.7% or more are used. After mixing these, they are high-frequency melted, and then cast in a water-cooled copper mold. 15
．． An ingot having a composition of 5Nd 7.5B 77Fe was obtained.

その後このインゴットを、スタンプミルにより粗粉砕し
、次にボールミルにより微粉砕し、平均粒度３．ＯＡｌ
ｍの微粉末を得た。Thereafter, this ingot was coarsely ground using a stamp mill, and then finely ground using a ball mill, with an average particle size of 3. OAl
A fine powder of m was obtained.

この微粉末を金型に挿入し、２０　ｋＯａの磁界中で配
向し、磁界に平行方向に、１．５　ｔ４の圧力で成形し
た。This fine powder was inserted into a mold, oriented in a magnetic field of 20 kOa, and molded at a pressure of 1.5 t4 in a direction parallel to the magnetic field.

得られた成形体を、１１（）０℃、１時間、　Ａｒ雰囲
気中、の条件で焼結し、長さ２０１ＴｌｌＴＩ×幅１０
＋ｎｍＸ厚み１０ｍ１Ｔ１寸法の焼結体を得た。The obtained molded body was sintered under the conditions of 11()0°C for 1 hour in an Ar atmosphere, and the length was 201TllTI×width 10
A sintered body with dimensions of +nm x thickness 10m1T1 was obtained.

そして焼結体より、長さ２．７５　ｍｍＸ幅０．７ｍｍ
Ｘ厚み０．７１ＴｌｌＴ１寸法の試験片に切出したのち
、真空度２Ｘ１０″″４　Ｔｏｒｒの石英管内に、陶金
属と共に挿入し、ｉ　ｏｏｏ℃、５時間加熱して、試料
全面に、１００人〜２０００人のＮｄ薄膜層を被着させ
た。And from the sintered body, length 2.75 mm x width 0.7 mm
After cutting into a test piece with dimensions of X thickness 0.71TllT1, it was inserted into a quartz tube with a vacuum degree of 2X10''''4 Torr together with a ceramic metal, heated at 100°C for 5 hours, and the whole surface of the sample was exposed to 100 to 2000 A thin layer of Nd was deposited.

ざらにＡｒ中での８００℃、　１時間と６３０℃、１．
５時間の２段時効処理を施して、被研削加工面に体心立
方相を形成した永久磁石を作製した。Roughly 800°C in Ar for 1 hour and 630°C, 1.
A two-stage aging treatment for 5 hours was performed to produce a permanent magnet in which a body-centered cubic phase was formed on the surface to be ground.

また、上記の試験片をＮｄ薄膜層を被着することなく直
ちに時効処理した比較試験片を作製した。In addition, a comparative test piece was prepared by immediately aging the above test piece without applying the Nd thin film layer.

得られた各永久磁石材料の減磁曲線を第１図に示し、ま
た、Ｂｒ、　　ｉＨｃ及び（ＢＨ）ｍａｘの値を、振動
試料型磁力計（ＶＳＨ）を用いて測定して第１表にその
結果を示す。曲線ａはＮｄ薄膜層を有する本発明永久磁
石で、曲線すは比較例永久磁石の場合である。The demagnetization curves of each of the obtained permanent magnet materials are shown in Figure 1, and the values of Br, iHc and (BH)max were measured using a vibrating sample magnetometer (VSH) and are shown in Table 1. The results are shown below. Curve a is for the permanent magnet of the present invention having a Nd thin film layer, and curve 2 is for the comparative permanent magnet.

第１表 実施例２ 出発原料として、純度９９．９％の電解鉄、フェロボロ
ン合金、純度９９．７％以上のＮｄを使用し、これらを
配合後高周波溶解し、その後水冷銅鋳型に鋳造し、１５
．５Ｍ７．５８７７Ｆａなる組成の鋳塊を得た。Table 1 Example 2 Electrolytic iron with a purity of 99.9%, ferroboron alloy, and Nd with a purity of 99.7% or more were used as starting materials, and after blending these, they were high-frequency melted, and then cast in a water-cooled copper mold. 15
．． An ingot having a composition of 5M7.5877Fa was obtained.

その後このインゴットを、スタンプミルにより粗粉砕し
、次にボールミルにより微粉砕し、平均粒度３．０μｍ
の微粉末を得た。Thereafter, this ingot was coarsely pulverized using a stamp mill, and then finely pulverized using a ball mill to obtain an average particle size of 3.0 μm.
A fine powder was obtained.

この微粉末を金型に挿入し、２０　ｋｏｅの磁界中で配
向し、磁界に平行方向に、１．５ｔＪの圧力で成形した
。This fine powder was inserted into a mold, oriented in a magnetic field of 20 koe, and molded at a pressure of 1.5 tJ in a direction parallel to the magnetic field.

得られた成形体を、１１００℃、１時間、　Ａｒ雰囲気
中、の条件で焼結し、長さ２０ｍｍＸ幅１０ｍｍＸ厚み
１０ｍｍ寸法の焼結体を得た。The obtained molded body was sintered at 1100° C. for 1 hour in an Ar atmosphere to obtain a sintered body having dimensions of 20 mm in length, 10 mm in width, and 10 mm in thickness.

そして焼結体より、長ざ２０ｍｍＸ幅５ｍｍＸ厚み１０
ｍｍ寸法の試験片に切出して厚みを暫時減少させた種々
の試験片を得たのち、真空度２ｘｌＯ−４Ｔｏｒｒの石
英管内に、陶金属と共に挿入し、１００Ｇ’Ｃ，５時間
加熱して、試料全面に、１００人〜２０００人の陶薄膜
層を被着させた。And from the sintered body, length 20mm x width 5mm x thickness 10
After obtaining various test pieces whose thickness was temporarily reduced by cutting them into mm-sized test pieces, they were inserted into a quartz tube with a vacuum degree of 2xlO-4 Torr together with a ceramic metal, and heated at 100 G'C for 5 hours. A ceramic thin film layer of 100 to 2000 layers was applied over the entire surface.

さらにＡｔ中での８００’Ｃ，１時間と６３０″Ｃ，１
，５時間の２段時効処理を施して、被研削加工面に体心
立方相を形成したこの発明による永久磁石を作製した。Furthermore, 800'C, 1 hour and 630''C, 1 hour in At
A permanent magnet according to the present invention in which a body-centered cubic phase was formed on the surface to be ground was produced by subjecting it to two-stage aging treatment for 5 hours.

また、上記の種々厚みのの試験片をＮｄｎ膜層を設ける
ことなく直ちに時効処理した比較試験片を作製した。Comparative test pieces were also prepared by immediately aging the above test pieces having various thicknesses without providing an Ndn film layer.

得られた各永久磁石材料の３ｒ、１ｌ−ＩＣ及び（ＢＨ
）ｍａｘ値を、振動試料型磁力計（ＶＳＨ）を用いて測
定して第２図にその結果を示す。曲線ａはＮｄ薄膜層を
有する本発明永久磁石で、曲線すは比較例永久磁石の場
合である。3r, 1l-IC and (BH
)max value was measured using a vibrating sample magnetometer (VSH), and the results are shown in FIG. Curve a is for the permanent magnet of the present invention having a Nd thin film layer, and curve 2 is for the comparative permanent magnet.

第１図、第１表及び第２図の結果から明らかなように、
Ｎｄを主成分とする体心立方相からなる蒸着層が、研削
加工面の磁気特性劣化防止に極めて有効であり、特に、
製品厚みが薄いものほど、その効果が著しいことが分る
。As is clear from the results in Figure 1, Table 1, and Figure 2,
A deposited layer consisting of a body-centered cubic phase mainly composed of Nd is extremely effective in preventing deterioration of the magnetic properties of the ground surface, and in particular,
It can be seen that the thinner the product, the more remarkable the effect.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は永久磁石材料の減磁曲線を示す図である。第２
図は永久磁石材料試験片厚みと３ｒ。 ｉＨｃ及び（ＢＨ）ｍａＸどの関係を示すグラフである
。 出願人　　住友特殊金属株式会社 代理人　　押　　１）　良　　久曜駅 第１図 −Ｈ（ＫＯｅ） 第２図 厚　さくＩＥＢ） １頁の続き 箔　明　者　　広　　沢　　　　　哲　　大阪府三島郡
島本町江ノ社山崎製作所内FIG. 1 is a diagram showing a demagnetization curve of a permanent magnet material. Second
The figure shows the thickness of a permanent magnet material specimen and 3r. It is a graph showing the relationship between iHc and (BH)maX. Applicant Sumitomo Special Metals Co., Ltd. Agent Press 1) Good Hisayo Station Figure 1-H (KOe) Figure 2 Thickness IEB) 1 page continuation foil Akira Tetsu Hirozawa Enosha, Shimahonmachi, Mishima-gun, Osaka Prefecture Inside Yamazaki Factory

Claims (1)

【特許請求の範囲】 １　Ｒ（ＲはＮｄ、Ｐｒ、Ｄｙ、Ｈｏ、Ｔｂのうち少な
くとも１種あるいはさらに、Ｌａ、Ｃｅ、Ｓｍ、Ｃｄ、
Ｅｒ、Ｅｕ、Ｔｍ、Ｙｂ、Ｌａ、Ｙのうち少なくとも１
種からなる）１０％〜３０原子％、 Ｂ２原子％〜２８原子％、 Ｆｅ６５原子％〜８０原子％を主成分とし、主相が正方
晶相からなる体積が２．５ｃｍ＾３以下あるいは厚みが
５．０ｍｍ以下の焼結磁石体の被研削加工面に、Ｎｄを
主成分とする体心立方相からなる蒸着層を有することを
特徴する永久磁石材料。[Claims] 1 R (R is at least one of Nd, Pr, Dy, Ho, Tb, or furthermore, La, Ce, Sm, Cd,
At least one of Er, Eu, Tm, Yb, La, Y
The main components are 10% to 30 atomic% (consisting of seeds), 28 atomic% to B2 atomic%, and 65 atomic% to 80 atomic% Fe, and the main phase is a tetragonal phase with a volume of 2.5 cm^3 or less or a thickness of A permanent magnet material characterized by having a deposited layer of a body-centered cubic phase containing Nd as a main component on a surface to be ground of a sintered magnet body of 5.0 mm or less.