JPS63254702A - Manufacture of corrosion resisting permanent magnet - Google Patents
Manufacture of corrosion resisting permanent magnetInfo
- Publication number
- JPS63254702A JPS63254702A JP62090046A JP9004687A JPS63254702A JP S63254702 A JPS63254702 A JP S63254702A JP 62090046 A JP62090046 A JP 62090046A JP 9004687 A JP9004687 A JP 9004687A JP S63254702 A JPS63254702 A JP S63254702A
- Authority
- JP
- Japan
- Prior art keywords
- permanent magnet
- atomic
- less
- magnet
- sintered
- 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
- 238000005260 corrosion Methods 0.000 title claims abstract description 23
- 230000007797 corrosion Effects 0.000 title claims abstract description 23
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 229910000510 noble metal Inorganic materials 0.000 claims abstract description 9
- 229910052779 Neodymium Inorganic materials 0.000 claims abstract description 8
- 229910052692 Dysprosium Inorganic materials 0.000 claims abstract description 7
- 229910052777 Praseodymium Inorganic materials 0.000 claims abstract description 7
- 239000010953 base metal Substances 0.000 claims abstract description 7
- 229910052802 copper Inorganic materials 0.000 claims abstract description 7
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 7
- 229910052718 tin Inorganic materials 0.000 claims abstract description 6
- 229910052772 Samarium Inorganic materials 0.000 claims abstract description 5
- 229910052737 gold Inorganic materials 0.000 claims abstract description 5
- 229910052697 platinum Inorganic materials 0.000 claims abstract description 5
- 229910052684 Cerium Inorganic materials 0.000 claims abstract description 4
- 229910052775 Thulium Inorganic materials 0.000 claims abstract description 4
- 229910052769 Ytterbium Inorganic materials 0.000 claims abstract description 4
- 229910052746 lanthanum Inorganic materials 0.000 claims abstract description 4
- 229910052763 palladium Inorganic materials 0.000 claims abstract description 4
- 229910052709 silver Inorganic materials 0.000 claims abstract description 4
- 229910052688 Gadolinium Inorganic materials 0.000 claims abstract description 3
- 238000007772 electroless plating Methods 0.000 claims description 6
- 239000010409 thin film Substances 0.000 claims description 3
- 238000001947 vapour-phase growth Methods 0.000 claims description 2
- 229910052691 Erbium Inorganic materials 0.000 claims 1
- 229910052693 Europium Inorganic materials 0.000 claims 1
- 229910052789 astatine Inorganic materials 0.000 claims 1
- 230000006866 deterioration Effects 0.000 abstract description 12
- 229910052742 iron Inorganic materials 0.000 abstract description 8
- 229910052751 metal Inorganic materials 0.000 abstract description 8
- 239000002184 metal Substances 0.000 abstract description 8
- 238000000034 method Methods 0.000 abstract description 7
- 239000011247 coating layer Substances 0.000 abstract description 5
- RKTYLMNFRDHKIL-UHFFFAOYSA-N copper;5,10,15,20-tetraphenylporphyrin-22,24-diide Chemical compound [Cu+2].C1=CC(C(=C2C=CC([N-]2)=C(C=2C=CC=CC=2)C=2C=CC(N=2)=C(C=2C=CC=CC=2)C2=CC=C3[N-]2)C=2C=CC=CC=2)=NC1=C3C1=CC=CC=C1 RKTYLMNFRDHKIL-UHFFFAOYSA-N 0.000 abstract description 4
- 239000013078 crystal Substances 0.000 abstract description 4
- 229910052765 Lutetium Inorganic materials 0.000 abstract description 3
- 229910052771 Terbium Inorganic materials 0.000 abstract description 3
- 229910052727 yttrium Inorganic materials 0.000 abstract description 3
- 229910052689 Holmium Inorganic materials 0.000 abstract description 2
- 239000002075 main ingredient Substances 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 17
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 11
- 238000007747 plating Methods 0.000 description 11
- 229910052761 rare earth metal Inorganic materials 0.000 description 11
- 239000012071 phase Substances 0.000 description 8
- 239000010410 layer Substances 0.000 description 6
- 150000002910 rare earth metals Chemical class 0.000 description 6
- 229910045601 alloy Inorganic materials 0.000 description 5
- 239000000956 alloy Substances 0.000 description 5
- 230000004907 flux Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 230000007423 decrease Effects 0.000 description 4
- 239000010408 film Substances 0.000 description 4
- 229910021126 PdPt Inorganic materials 0.000 description 3
- 230000032683 aging Effects 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 2
- 150000002500 ions Chemical class 0.000 description 2
- 239000002932 luster Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- KWSLGOVYXMQPPX-UHFFFAOYSA-N 5-[3-(trifluoromethyl)phenyl]-2h-tetrazole Chemical compound FC(F)(F)C1=CC=CC(C2=NNN=N2)=C1 KWSLGOVYXMQPPX-UHFFFAOYSA-N 0.000 description 1
- 239000003929 acidic solution Substances 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- JZQOJFLIJNRDHK-CMDGGOBGSA-N alpha-irone Chemical compound CC1CC=C(C)C(\C=C\C(C)=O)C1(C)C JZQOJFLIJNRDHK-CMDGGOBGSA-N 0.000 description 1
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 1
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 1
- 235000011130 ammonium sulphate Nutrition 0.000 description 1
- 229910052797 bismuth Inorganic materials 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 230000005347 demagnetization Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 229910001004 magnetic alloy Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 150000002815 nickel Chemical class 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- NLJMYIDDQXHKNR-UHFFFAOYSA-K sodium citrate Chemical compound O.O.[Na+].[Na+].[Na+].[O-]C(=O)CC(O)(CC([O-])=O)C([O-])=O NLJMYIDDQXHKNR-UHFFFAOYSA-K 0.000 description 1
- 239000001509 sodium citrate Substances 0.000 description 1
- 229910001379 sodium hypophosphite Inorganic materials 0.000 description 1
- 235000012976 tarts Nutrition 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Manufacturing Cores, Coils, And Magnets (AREA)
- Chemically Coating (AREA)
- Physical Vapour Deposition (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Hard Magnetic Materials (AREA)
Abstract
Description
【発明の詳細な説明】
利用産業分野
この発明は、高磁気特性を有しかつ耐食性にすぐれたＦ
ｅ−Ｂ−Ｒ系永久磁石の製造方法に係り、耐食性、特に
８０℃、相対湿度９０％の雰囲気中に長時間放置した場
合の初期磁石特性からの劣化が少なく、きわめて安定し
た磁石特性を有するＦｅ−Ｂ−Ｒ系永久磁石の製造方法
に関する。[Detailed description of the invention] Industrial field of application The present invention is directed to an F material having high magnetic properties and excellent corrosion resistance.
Regarding the manufacturing method of e-B-R series permanent magnets, it has corrosion resistance, especially when left in an atmosphere of 80°C and 90% relative humidity, there is little deterioration from the initial magnetic properties, and it has extremely stable magnetic properties. The present invention relates to a method of manufacturing a Fe-BR permanent magnet.
背景技術
先に、ＮｄやＰｒを中心とする資源的に豊富な軽希土類
を用いてＢ、Ｆｅを主成分とし、高価なＳｍやＣｏを含
有せず、従来の希土類コバルト磁石の最高特性を大幅に
越える新しい高性能永久磁石として、Ｆｅ−Ｂ−Ｒ系永
久磁石が提案されている（特開昭５９−４６００８号公
報、特開昭５９−８９４０１号公報）。Background technology We use resource-rich light rare earths such as Nd and Pr, with B and Fe as the main components, and do not contain expensive Sm or Co, greatly improving the best characteristics of conventional rare earth cobalt magnets. Fe-B-R permanent magnets have been proposed as new high-performance permanent magnets that exceed the above (Japanese Patent Application Laid-open No. 59-46008 and Japanese Patent Application Laid-Open No. 59-89401).
前記磁石合金のキュリ一点は、一般に、３００℃〜３７
０℃であるが、Ｆｅの一部をＣｏにて置換することによ
り、より高いキュリ一点を有するＦｅ−Ｂ−Ｒ系永久磁
石（特開昭５９−６４７３３号、特開昭５９−１３２１
０４号）を得ており、さらに、前記Ｃｏ含有のＦｅ−Ｂ
−Ｒ系希土類永久磁石と同等以上のキュリ一点並びによ
り高い（ＢＨ）ｍａｘを有し、その温度特性、特に、ｉ
Ｈｃを向上させるため、希土類元素（Ｒ）としてＮｄや
Ｐｒ等の軽希土類を中心としたＣｏ含有のＦｅ−Ｂ−Ｒ
系希土類永久磁石のＲの一部にＤｙ、 Ｔｂ等の重希土
類のうち少なくとも１種を含有することにより、２５Ｍ
ＧＯｅ以上の極めて高い（ＢＨ）ｍａｘを保有したまま
で、ｉＨｃをさらに向上させたＣｏ含有のＦｅ−Ｂ−Ｒ
系希土類永久磁石が提案（特開昭６０−３４００５号）
されている。The Curie point of the magnetic alloy is generally 300°C to 37°C.
0°C, but by replacing a part of Fe with Co, Fe-B-R permanent magnets with a higher Curie point (JP-A-59-64733, JP-A-59-1321
No. 04), and furthermore, the Co-containing Fe-B
-It has a Curie point equal to or higher than R-based rare earth permanent magnets and a higher (BH) max, and its temperature characteristics, especially i
In order to improve Hc, Fe-B-R containing Co, mainly light rare earths such as Nd and Pr, as rare earth elements (R) is used.
By containing at least one kind of heavy rare earths such as Dy and Tb in a part of R of the rare earth permanent magnet, 25M
Co-containing Fe-B-R that further improves iHc while maintaining an extremely high (BH)max higher than GOe.
Rare earth permanent magnet proposed (Japanese Patent Application Laid-Open No. 60-34005)
has been done.
しかしながら、上記のすぐれた磁気特性を有す１□るＦ
ｅ−Ｂ−Ｒ光磁気異方性焼結体からなる永久磁石は主成
分として、空気中で酸化し次第に安定な酸化物を生成し
易い希土類元素及び鉄を含有するため、磁気回路に組込
んだ場合に、磁石表面に生成する酸化物により、磁気回
路の出力低下及び磁気回路間のばらつきを惹起し、また
、表面酸化物の脱落による周辺機器への汚染の問題があ
った。However, 1□F with the above excellent magnetic properties
Permanent magnets made of e-BR magneto-optical anisotropic sintered bodies contain rare earth elements and iron, which tend to oxidize in the air and gradually form stable oxides, so they cannot be incorporated into magnetic circuits. In this case, oxides generated on the magnet surface cause a decrease in the output of the magnetic circuit and variations between the magnetic circuits, and there is also the problem of contamination of peripheral equipment due to the surface oxide falling off.
そこで、上記のＦｅ−Ｂ−Ｒ系永久磁石の耐食性の改善
のため、磁石体表面に無電解めっき法あるいは電解めっ
き法により耐食性金属めっき層を被覆した永久磁石（特
願昭５８−１６２３５０号）が提案されているが、この
めっき法では永久磁石体が焼結体で有孔性のため、この
孔内にめっき前処理での酸性溶液またはアルカリ溶液が
残留し、経年変化とともに腐食する恐れがあり、また磁
石体の耐薬品性が劣るため、めっき時に磁石表面が腐食
されて密着性、防蝕性が劣る問題があった。Therefore, in order to improve the corrosion resistance of the above-mentioned Fe-B-R permanent magnet, a permanent magnet whose surface is coated with a corrosion-resistant metal plating layer by electroless plating or electrolytic plating (Japanese Patent Application No. 162350/1982) However, in this plating method, since the permanent magnet body is a sintered body and has pores, there is a risk that acidic or alkaline solutions from plating pretreatment may remain in the pores, leading to corrosion over time. Moreover, since the chemical resistance of the magnet body is poor, there is a problem that the magnet surface is corroded during plating, resulting in poor adhesion and corrosion resistance.
従来技術の問題点
前記Ｆｅ−Ｂ−Ｒ系永久磁石表面に耐食性めっきを設け
るが、永久磁石体が焼結体で有孔性のため、密着性、防
蝕性が劣る問題があり、また、温度６０℃、相対湿度９
０％の条件下の耐食性試験でも１００時間放置にて、磁
石特性は初期磁石特性の１０％以上劣化し、非常に不安
定であった。Problems with the Prior Art Although corrosion-resistant plating is provided on the surface of the Fe-B-R permanent magnet, since the permanent magnet body is a sintered body and porous, there is a problem that adhesion and corrosion resistance are poor, and 60℃, relative humidity 9
Even in the corrosion resistance test under the condition of 0%, the magnetic properties deteriorated by more than 10% of the initial magnetic properties after being left for 100 hours, and were extremely unstable.
発明の目的
この発明は、Ｆｅ−Ｂ−Ｒ系永久磁石の耐食性の改善を
目的とし、特に温度８０℃、相対湿度９０％の雰囲気条
件下で長時間放置した場合の初期磁石特性からの劣化を
極力少なくし、安定した高磁石特性を有するＦｅ−Ｂ−
Ｒ系永久磁石を安価に提供できる製造方法を目的とする
。Purpose of the Invention The present invention aims to improve the corrosion resistance of Fe-B-R permanent magnets, and in particular to prevent deterioration from the initial magnetic properties when left for a long time under atmospheric conditions of a temperature of 80°C and a relative humidity of 90%. Fe-B-, which has stable and high magnetic properties with as little amount as possible
The purpose of this invention is to provide a manufacturing method that can provide R-based permanent magnets at low cost.
発明の構成
この発明は、すぐれた耐食性、特に、温度８０℃、相対
湿度９０％の雰囲気条件下で長時間放置した場合におい
ても、その磁石特性が安定したＦｅ−Ｂ−Ｒ系永久磁石
の製造方法を目的に、永久磁石体の表面処理について種
々研究した結果、特定成分を有するＦｅ−Ｂ−Ｒ系焼結
磁石体表面に、貴金属と卑金属とからなる金属被覆層を
被着することにより、すぐれた耐食性ときわめて安定し
た磁石特性が得られることを知見し、この発明を完成し
たものである。Structure of the Invention The present invention is directed to the production of Fe-B-R permanent magnets that have excellent corrosion resistance and, in particular, have stable magnetic properties even when left for long periods of time under atmospheric conditions of a temperature of 80°C and a relative humidity of 90%. As a result of various studies on the surface treatment of permanent magnet bodies with the aim of developing methods, we found that by applying a metal coating layer made of noble metals and base metals to the surface of Fe-BR-based sintered magnets having specific components, This invention was completed after discovering that excellent corrosion resistance and extremely stable magnetic properties could be obtained.
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種あるいはさらに、Ｌａ、 Ｃｅ、 Ｓｍ
、 Ｇｄ、 Ｅｒ５Ｅｕ、Ｔｍ、 Ｙｂ、 Ｌｕ、 Ｙ
のうち少なくとも１種からなる）１０％〜３０原子％、
Ｂ２２原子〜２８原子％、
Ｆｅ ６５原子％〜８０原子％を主成分とし、主相が正
方晶相からなる焼結永久磁石体表面に、
Ｐｄ、 Ａｇ、 Ｐｔ及びＡｕ等から選ばれた少なくと
も１種の貴金属の薄膜を気相成膜法にて設け、その後さ
らに、Ｎｉ、 Ｃｕ、 Ｓｎ及びＣＯ等から選ばれた少
なくとも１種の卑金属の無電解めっきを施すことにより
、
温度８０℃、相対湿度９０％の条件下で５００時間放置
したときの初期磁石特性からの劣化が１０％以下である
ことを特徴とする耐食性永久磁石の製造方法である。That is, the present invention provides R (R is at least one of Nd, Pr, Dy, Ho, Tb, or furthermore, La, Ce, Sm
, Gd, Er5Eu, Tm, Yb, Lu, Y
(consisting of at least one of the following) 10% to 30 at%, B22 to 28 at%, Fe 65 to 80 at%, and the main phase is a tetragonal phase on the surface of the sintered permanent magnet body. A thin film of at least one noble metal selected from , Pd, Ag, Pt, Au, etc. is provided by a vapor phase deposition method, and then a thin film of at least one noble metal selected from Ni, Cu, Sn, CO, etc. A method for manufacturing a corrosion-resistant permanent magnet, characterized in that the deterioration from the initial magnetic properties is 10% or less when left for 500 hours at a temperature of 80°C and a relative humidity of 90% by applying electroless plating. It is.
この発明による金属被覆層を有するＦｅ−Ｂ−Ｒ系永久
磁石が、苛酷な雰囲気条件下において、初期磁石特性か
らの劣化が少なく、磁石特性値が極めて安定する理由は
未だ明らかではない。It is not yet clear why the Fe-B-R permanent magnet having the metal coating layer according to the present invention exhibits little deterioration from the initial magnetic characteristics and extremely stable magnetic characteristic values under severe atmospheric conditions.
しかし、前記Ｆｅ−Ｂ−Ｒ系焼結磁石体表面に、めっき
法によりＮｉ、 Ｃｕ、 Ｓｎ、及びＣｏ等から選ばれ
た卑金属の少なくとも１種からなる金属層を被着した場
合は、温度６０℃、相対湿度９０％に１００時間放置の
苛酷な耐食性試験条件で、その磁石特性値は劣化し不安
定となるが、これに対して、前記焼結磁石体表面に、気
相成膜法にてＰｄ、 Ａｇ、 Ｐｔ、Ａｕ等から選ばれ
た少なくとも１種の貴金属層を設け、さらに、Ｎｉ、
Ｃｕ、 Ｓｎ、及びＣｏ等から選ばれた少なくとも１種
の卑金属の無電解めっきを施したこの発明による金属被
覆層を形成することにより、該金属被覆層は緻密となり
、湿気、ガス等の外部環境の変化に対して、永久磁石を
完全に保護できることが明らかとなった。However, when a metal layer made of at least one base metal selected from Ni, Cu, Sn, Co, etc. is deposited on the surface of the Fe-B-R based sintered magnet by a plating method, the temperature is 60°C. ℃ and 90% relative humidity for 100 hours, the magnetic properties deteriorate and become unstable.In contrast, the surface of the sintered magnet was At least one noble metal layer selected from Pd, Ag, Pt, Au, etc. is provided, and Ni,
By forming the metal coating layer according to the present invention, which is electroless plated with at least one base metal selected from Cu, Sn, Co, etc., the metal coating layer becomes dense and is free from external environments such as moisture and gas. It has become clear that permanent magnets can be completely protected against changes in
発明の好ましい実施態様
この発明において、焼結磁石体表面に設けたＰｄ、 Ａ
ｇ、 Ｐｔ、 Ａｕ等から選ばれた少なくとも１種から
なる貴金属層は、真空蒸着法やイオンスパッタ法等、公
知の気相成膜法にて設けるもので、前記貴金属層厚みは
１０人〜１００人が好ましい。Preferred Embodiment of the Invention In this invention, Pd, A provided on the surface of the sintered magnet body
The noble metal layer made of at least one selected from g, Pt, Au, etc. is formed by a known vapor phase film forming method such as a vacuum evaporation method or an ion sputtering method, and the thickness of the noble metal layer is 10 to 100%. People are preferred.
また、この発明において、Ｎｉ、 Ｃｕ、 Ｓｎ、及び
Ｃｏ等から選ばれた少なくとも１種の卑金属層は、無電
解めっきにて、２５、以下の厚みに被着されるのが好ま
しく、さらに好ましくは３〜２０ ｐｍ厚みであり、無
電解めっき法は公知のいずれの方法であっても利用でき
る。Further, in the present invention, the at least one base metal layer selected from Ni, Cu, Sn, Co, etc. is preferably deposited by electroless plating to a thickness of 25 mm or less, and more preferably. The thickness is 3 to 20 pm, and any known electroless plating method can be used.
永久磁石の成分限定理由
この発明による永久磁石に用いる希土類元素Ｒは、組成
の１０原子％〜３０原子％を占めるが、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、 Ｇｄ、 Ｅｒ１Ｅ
ｕ、Ｔｍ、 Ｙｂ、Ｌｕ、 Ｙのうち少なくとも１種を
含むものが好ましい。Reasons for limiting the composition of permanent magnets The rare earth elements R used in the permanent magnet according to the present invention account for 10 to 30 at% of the composition, and include Nd, Pr,
At least one of Dy, Ho, Tb, or additionally La, Ce, Sm, Gd, Er1E
Preferably, it contains at least one of u, Tm, Yb, Lu, and Y.
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、工業上人
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 manufacturing to the extent that it is industrially possible.
Ｒは、上記系永久磁石における、必須元素であって、１
０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、３ｏ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（Ｂｒ）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、１ｏ
原子％〜３ｏ原子％の範囲とする。R is an essential element in the above permanent magnet, and 1
If it is less than 0 atomic %, the crystal structure becomes a cubic structure that is the same as α-iron, so high magnetic properties, especially high coercive force, cannot be obtained. Therefore, the residual magnetic flux density (Br) decreases, and a permanent magnet with excellent characteristics cannot be obtained. Therefore, the rare earth element is 1o
The range is from atomic % to 3o atomic %.
Ｂは、この発明による永久磁石における、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 according to the present invention. If it is less than 2 at %, the rhombohedral structure becomes the main phase and high coercive force (iHc) cannot be obtained, and if it exceeds 28 at %, B-rich The number of non-magnetic phases 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、上記系永久磁石において、必須元素であり、６
５原子％未満では残留磁束密度（Ｂｒ）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 above-mentioned permanent magnet, and 6
If it is less than 5 at%, the residual magnetic flux density (Br) decreases, and 80
If it exceeds atomic%, high coercivity cannot be obtained, so Fe
The content is 65 atomic % to 80 atomic %.
また、この発明による永久磁石において、Ｆｅの一部を
Ｃｏ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、Ｃｏ置
換量がＦｅ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。Ｃｏの置換量がＦｅとｃｏの合
計量で５原子％〜１５原子％の場合は、（Ｂｒ）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
ために好ましい。Furthermore, in the permanent magnet according to the present invention, replacing a part of Fe with Co can improve the temperature characteristics without impairing the magnetic properties of the obtained magnet. If it exceeds %, the magnetic properties will deteriorate, which is not preferable. When the amount of Co substitution is 5 at % to 15 at % in total of Fe and co, (Br) 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Ｃ１３，５原子％以下のＰ
、２．５原子％以下のＳ、３．５原子％以下のＣｕ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 at% or less of C13, 5 at% or less of P
By replacing at least one of , 2.5 atomic % or less S, and 3.5 atomic % or less Cu, in a total amount of 4.0 atomic % or less, the manufacturability and cost reduction of permanent magnets can be improved. It is possible.
また、下記添加元素のうち少なくとも１種は、Ｒ−Ｂ−
Ｆｅ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。Furthermore, at least one of the following additional elements is R-B-
It can be added to Fe-based permanent magnets because it is effective in improving the coercive force and squareness of the demagnetization curve, improving manufacturability, and reducing costs.
９．５原子％以下のＡＩ、４．５原子％以下のＴｉ、９
．５原子％以下のＶ、８．５原子％以下のＣｒ、８．０
原子％以下のＭｎ、５．０原子％以下のＢｉ、９．５原
子％以下のＮｂ、 ９．５原子％以下のＴａ。9.5 atom% or less of AI, 4.5 atom% or less of Ti, 9
．． 5 at% or less V, 8.5 at% or less Cr, 8.0
Mn of atomic% or less, Bi of 5.0 atomic% or less, Nb of 9.5 atomic% or less, and Ta of 9.5 atomic% or less.
９．５原子％以下のＭｏ、９．５原子％以下のＷ、２．
５原子％以下のｓｂ、７ 原子％以下のＧｅ、３．５原
子％以下のＳｎ、５．５原子％以下のＺｒ、９．０原子
％以下のＮｉ、９．０原子％以下のＳｉ、ｉ、ｉ原子％
以下のＺｎ、５，５原子％以下のＨｆ、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％以下を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。Mo of 9.5 atomic % or less, W of 9.5 atomic % or less, 2.
5 at % or less sb, 7 at % or less Ge, 3.5 at % or less Sn, 5.5 at % or less Zr, 9.0 at % or less Ni, 9.0 at % or less Si, i, i atomic%
At least one of the following Zn and 5.5 atomic % or less of Hf is added. However, if two or more types are contained, the maximum content is less than or equal to the atomic % of the one with the maximum value among the added elements. By containing , it is possible to increase the coercive force of the permanent magnet.
結晶相は主相が正方晶であることが、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ある。It is essential that the main crystalline phase be tetragonal in order to produce a sintered permanent magnet with superior magnetic properties than a fine and uniform alloy powder.
また、この発明による永久磁石は平均結晶粒径が１〜５
Ｏｆｉ、、の範囲にある正方晶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 according to the present invention has an average crystal grain size of 1 to 5.
It is characterized by having a main phase of a compound having a tetragonal crystal structure in the range of .Ofi, and containing a non-magnetic phase (excluding oxide phase) of 1% to 50% by volume.
この発明による永久磁石は、保磁力ｉＨｃ≧１ｋＯｅ、
残留磁束密度Ｂｒ＞４ｋＧ、を示し、最大エネルギー積
（ＢＨ）ｍａｘは、（ＢＨ）ｍａｘ≧１０ＭＧＯｅを示
し、最大値は２５ＭＧＯｅ以上に達する。The permanent magnet according to the present invention has a coercive force iHc≧1kOe,
The residual magnetic flux density Br>4kG is shown, and the maximum energy product (BH)max is (BH)max≧10MGOe, and the maximum value reaches 25MGOe or more.
また、この発明による永久磁石のＲの主成分が、その５
０％以上をＮｄ及びＰｒを主とする軽希土類金属が占め
る場合で、Ｒ１２原子％〜２ｏ原子％、Ｂ４４原子〜２
４原子％、Ｆｅ ７４原子％〜８ｏ原子％、を主成分と
するとき、（ＢＨ）ｍａｘ ３５ＭＧＯｅ以上のすぐれ
た磁気特性を示し、特に軽希土類金属がＮｄの場合には
、その最大値が４５ＭＧＯｅ以上に達する。Further, the main component of R of the permanent magnet according to the present invention is 5
In the case where 0% or more is occupied by light rare earth metals mainly consisting of Nd and Pr, R12 atom% to 2o atom%, B44 atom to 2
When the main component is 4 at% Fe, 74 at% to 80 at% Fe, it exhibits excellent magnetic properties of (BH)max 35MGOe or more, and especially when the light rare earth metal is Nd, the maximum value is 45MGOe. reach more than that.
また、８０℃、相対湿度９０％の環境に長時間放置する
耐食試験で、極めて高い耐食性を示すこの発明による永
久磁石として、
Ｎｄ ｆｌａｔ％〜１５ａｔ％、Ｄｙ ０．２ａｔ％〜
３．Ｏａｔ％、かつＮｄとＤｙの総量が１２ａｔ％〜１
７ａｔ％であり、Ｂ ５ａｔ％〜８ａｔ％、Ｃｏ Ｏ，
５ａｔ％〜１３ａｔ％、Ａｅ Ｏ，５ａｔ％〜４ａｔ％
、Ｃ１０００ｐｐｍ以下を含有し、残部Ｆｅ及び不可避
的不純物からなる場合が好ましい。In addition, as a permanent magnet according to the present invention that shows extremely high corrosion resistance in a corrosion resistance test where it is left in an environment of 80° C. and 90% relative humidity for a long time, Nd flat% ~ 15 at%, Dy 0.2 at% ~
3. Oat%, and the total amount of Nd and Dy is 12at% to 1
7at%, B 5at% to 8at%, CoO,
5at%~13at%, AeO, 5at%~4at%
, C1000 ppm or less, with the remainder being Fe and unavoidable impurities.
実施例 以下に、実施例及び比較例によりこの発明を説明する。Example This invention will be explained below with reference to Examples and Comparative Examples.
去施皿
出発原料として、純度９９．９％の電解鉄、８１９．４
％含有のフェロボロン合金、純度９９．７％以上のＮｄ
、 Ｄｙを使用し、これらを配合した後、高周波溶解し
て鋳造し、１４Ｎｄ−０，５Ｄｙ−７Ｂ−７８，５Ｆｅ
なる組成（ａｔ％）の鋳塊を得た。Electrolytic iron with a purity of 99.9%, 819.4
% ferroboron alloy, Nd with a purity of 99.7% or more
, Dy, and after blending these, high frequency melting and casting were performed to obtain 14Nd-0,5Dy-7B-78,5Fe.
An ingot having the following composition (at%) was obtained.
その後、この鋳塊を微粉砕し、平均粒度３ｐｍの微粉砕
粉を得た。Thereafter, this ingot was finely ground to obtain a finely ground powder with an average particle size of 3 pm.
この微粉砕粉をプレス装置の金型に装入し、１２ｋＯｅ
の磁界中で配向し、磁界に平行方向に１．５ｔａｒｔ／
ｃｍ２の圧力で成形して、得られた成形体を１１００℃
、２時間、舒雰囲気中の条件で焼結後、更にＡｒ雰囲気
中でＳＯＯ℃、１時間、次に６３０”Ｃ１１，５時間の
時効処理を行い、焼結磁石体を得た。This finely pulverized powder was charged into a mold of a press machine, and 12 kOe was produced.
Oriented in a magnetic field of 1.5 tart/parallel to the magnetic field.
The molded product obtained by molding at a pressure of cm2 was heated to 1100°C.
After sintering in a So atmosphere for 2 hours, aging treatment was performed at SOO° C. for 1 hour in an Ar atmosphere and then for 5 hours at 630"C11 to obtain a sintered magnet.
得られた永久磁石体から径１２ｍｍＸ厚み２ｍｍ寸法の
試験片を得た。A test piece with a diameter of 12 mm and a thickness of 2 mm was obtained from the obtained permanent magnet body.
この焼結磁石体試験片の磁石特性を第１表に示す。The magnetic properties of this sintered magnet test piece are shown in Table 1.
次に、得られた焼結磁石体を、真空度０．０５Ｔｏｒｒ
の雰囲気でイオンスパッター法により、ＰｄＰｔ合金膜
を厚み５０人に被着し、ＰｄＰｔ合金膜を表面に被着し
たＮｄ−Ｄｙ−Ｂ−Ｆｅ系永久磁石を得た。Next, the obtained sintered magnet body was placed at a vacuum degree of 0.05 Torr.
A PdPt alloy film was deposited to a thickness of 50 mm by ion sputtering in an atmosphere of 100 mL to obtain a Nd-Dy-B-Fe permanent magnet having a PdPt alloy film deposited on its surface.
さらに、Ｎｉ濃度０．１ｒｒｕｙｌｌｅ、次亜リン酸ナ
トリウム０．１５ ｍｔｙｌｌｅ １クエン酸ナトリウ
ム０．２ｍｏＬ／ｅ 、硫酸アンモニウム０．５ｒｒｕ
ｙｌ／ｅで、ｐＨが９．０のニッケル化学めっき液を用
意し、このニッケル化学めっき液に、前記のＰｄＰｔ合
金膜を表面に被着したＮｄ−Ｄ３ｒ−Ｂ−Ｆｅ系永久磁
石を、８０℃で６０分間浸漬した後、水洗乾燥した。Furthermore, Ni concentration 0.1 rruyl, sodium hypophosphite 0.15 mtyl 1 sodium citrate 0.2 moL/e, ammonium sulfate 0.5 rru
Prepare a nickel chemical plating solution with yl/e and pH of 9.0, and add the Nd-D3r-B-Fe based permanent magnet with the above-mentioned PdPt alloy film on the surface to this nickel chemical plating solution. After being immersed at ℃ for 60 minutes, it was washed with water and dried.
生成Ｎｉめっき厚は５．３Ｐｒｎであり、金属光沢を有
していた。The resulting Ni plating thickness was 5.3 Prn and had metallic luster.
また、表面処理後のこの発明による永久磁石の磁石特性
を第１表に表す。Further, the magnetic properties of the permanent magnet according to the present invention after surface treatment are shown in Table 1.
その後、得られたこの発明の永久磁石を、温度８０℃、
相対湿度９０％の条件下で５００時間放置した後の磁石
特性、及びその劣化状況を測定した。その結果を第１表
に表す。Thereafter, the obtained permanent magnet of the present invention was heated at a temperature of 80°C.
The magnetic properties and the state of deterioration thereof were measured after being left for 500 hours under conditions of relative humidity of 90%. The results are shown in Table 1.
里箆皿
実施例と同一組成、同一製造条件で得られた焼結磁石体
に、実施例１のめっき条件と同一条件で無電解めっきを
行った。生成Ｎｉめっき厚は工２１１ｒｎであり、鈍い
金属光沢を有していた。Electroless plating was performed under the same plating conditions as in Example 1 on a sintered magnet body obtained under the same composition and manufacturing conditions as in the Satoshi Dish Example. The resulting Ni plating had a thickness of 211 rn and had a dull metallic luster.
この比較焼結磁石体の耐食試験前後の磁石特性の劣化は
、温度６０℃、相対湿度９０％の条件下で１００時間保
持にて、その磁石特性は１０．５％の劣化を生じ、その
後、急激に劣化は進行し、５００時間では全面に錆が発
生していた。The deterioration of the magnetic properties of this comparative sintered magnet body before and after the corrosion resistance test was as follows: When held for 100 hours at a temperature of 60°C and a relative humidity of 90%, the magnetic properties deteriorated by 10.5%. Deterioration progressed rapidly, and rust had formed on the entire surface after 500 hours.
この発明による永久磁石は、第１表の耐食試験前後の磁
石特性及び該特性の劣化率に明らかなように、すぐれた
初期磁石特性からの劣化が少なく、すぐれた耐食性と磁
石特性の安定性を有することが明らかである。The permanent magnet according to the present invention exhibits little deterioration from the excellent initial magnetic properties, and has excellent corrosion resistance and stability of the magnetic properties, as is clear from the magnet properties before and after the corrosion resistance test and the rate of deterioration of the properties in Table 1. It is clear that it has.
第１表
（耐食性試験後磁石特性）−僻効処理後磁石特性）磁気
特性劣化率（％）＝□
（時効処理後磁石特性）
発明の効果
この発明によるＦｅ−Ｂ−Ｒ系永久磁石体は、実施例の
如く、苛酷な耐食試験条件、特に、温度８０℃、相対湿
度９０％の条件下で、５００時間放置した後、その磁石
特性の劣化は初期磁石特性の１０％以下の低下にすぎず
、現在、最も要求されている高性能永久磁石として安価
に提供できる。Table 1 (Magnet properties after corrosion resistance test - Magnet properties after aging treatment) Magnetic property deterioration rate (%) = □ (Magnet properties after aging treatment) Effects of the invention The Fe-B-R permanent magnet body according to the present invention As in the example, after being left for 500 hours under severe corrosion resistance test conditions, particularly at a temperature of 80°C and a relative humidity of 90%, the deterioration of the magnetic properties was only 10% or less of the initial magnetic properties. First, it can be provided at a low cost as a high-performance permanent magnet, which is currently most in demand.
Claims (1)
くとも１種あるいはさらに、Ｌａ、Ｃｅ、Ｓｍ、Ｇｄ、
Ｅｒ、Ｅｕ、Ｔｍ、Ｙｂ、Ｌｕ、Ｙのうち少なくとも１
種からなる）１０原子％〜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
晶相からなる焼結永久磁石体表面に、 Ｐｄ、Ａｇ、Ｐｔ及びＡｕ等から選ばれた少なくとも１
種の貴金属の薄膜を気相成膜法にて設け、 その後さらに、Ｎｉ、Ｃｕ、Ｓｎ及びＣｏ等から選ばれ
た少なくとも１種の卑金属の無電解めっきを施すことを
特徴とする耐食性永久磁石の製造方法。[Claims] 1 R (R is at least one of Nd, Pr, Dy, Ho, Tb, or furthermore, La, Ce, Sm, Gd,
At least one of Er, Eu, Tm, Yb, Lu, Y
Pd, Pd, At least one selected from Ag, Pt, Au, etc.
A corrosion-resistant permanent magnet characterized in that a thin film of a noble metal is formed by a vapor phase deposition method, and then electroless plating of at least one base metal selected from Ni, Cu, Sn, Co, etc. is applied. Production method.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62090046A JPH0831363B2 (en) | 1987-04-13 | 1987-04-13 | Method for manufacturing corrosion-resistant permanent magnet |
| US07/172,395 US4942098A (en) | 1987-03-26 | 1988-03-24 | Corrosion resistant permanent magnet |
| US07/454,451 US4968529A (en) | 1987-03-26 | 1989-12-21 | Process for producing a corrosion resistant permanent magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62090046A JPH0831363B2 (en) | 1987-04-13 | 1987-04-13 | Method for manufacturing corrosion-resistant permanent magnet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63254702A true JPS63254702A (en) | 1988-10-21 |
| JPH0831363B2 JPH0831363B2 (en) | 1996-03-27 |
Family
ID=13987685
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62090046A Expired - Fee Related JPH0831363B2 (en) | 1987-03-26 | 1987-04-13 | Method for manufacturing corrosion-resistant permanent magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0831363B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4959273A (en) * | 1988-09-20 | 1990-09-25 | Sumitomo Special Metals Co., Ltd. | Corrosion-resistant permanent magnet and method for preparing the same |
| EP2680280A1 (en) | 2012-06-25 | 2014-01-01 | Jtekt Corporation | Method of manufacturing magnet and magnet |
| US9601246B2 (en) | 2012-02-27 | 2017-03-21 | Jtekt Corporation | Method of manufacturing magnet, and magnet |
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| JPS53114738A (en) * | 1977-03-18 | 1978-10-06 | Hitachi Metals Ltd | Surface treatment method of rare earth cobalt magnet |
| JPS6054406A (en) * | 1983-09-03 | 1985-03-28 | Sumitomo Special Metals Co Ltd | Permanent magnet having excellent oxidation resistance characteristic |
| JPS61150201A (en) * | 1984-12-24 | 1986-07-08 | Sumitomo Special Metals Co Ltd | Permanent magnet with excellent anticorrosion property |
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- 1987-04-13 JP JP62090046A patent/JPH0831363B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS53114738A (en) * | 1977-03-18 | 1978-10-06 | Hitachi Metals Ltd | Surface treatment method of rare earth cobalt magnet |
| JPS6054406A (en) * | 1983-09-03 | 1985-03-28 | Sumitomo Special Metals Co Ltd | Permanent magnet having excellent oxidation resistance characteristic |
| JPS61150201A (en) * | 1984-12-24 | 1986-07-08 | Sumitomo Special Metals Co Ltd | Permanent magnet with excellent anticorrosion property |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4959273A (en) * | 1988-09-20 | 1990-09-25 | Sumitomo Special Metals Co., Ltd. | Corrosion-resistant permanent magnet and method for preparing the same |
| US9601246B2 (en) | 2012-02-27 | 2017-03-21 | Jtekt Corporation | Method of manufacturing magnet, and magnet |
| EP2680280A1 (en) | 2012-06-25 | 2014-01-01 | Jtekt Corporation | Method of manufacturing magnet and magnet |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0831363B2 (en) | 1996-03-27 |
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