JP2002212750A - Film deposition method for r-t-b based magnet - Google Patents
Film deposition method for r-t-b based magnetInfo
- Publication number
- JP2002212750A JP2002212750A JP2001354169A JP2001354169A JP2002212750A JP 2002212750 A JP2002212750 A JP 2002212750A JP 2001354169 A JP2001354169 A JP 2001354169A JP 2001354169 A JP2001354169 A JP 2001354169A JP 2002212750 A JP2002212750 A JP 2002212750A
- Authority
- JP
- Japan
- Prior art keywords
- chemical conversion
- film
- rtb
- magnet
- coated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/0253—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets
- H01F41/026—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing permanent magnets protecting methods against environmental influences, e.g. oxygen, by surface treatment
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Treatment Of Metals (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
- Hard Magnetic Materials (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は新規なR-T-B系磁石
の皮膜形成方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel method for forming a film on an RTB magnet.
【０００２】[0002]
【従来の技術】希土類磁石の中でも特に錆び易いR−Fe
−B系磁石（ＲはＹを含む希土類元素の少なくとも１種
である。）の表面には従来より各種のめっきや化成皮膜
が被覆され、実用に供されている。特開昭60-63902号公
報には、Ｒ-Fe-Ｂ系磁石の表面に化成皮膜と樹脂層とを
順次積層して耐酸化性を向上した希土類磁石が開示され
ている。この公報の実施例１にはＲ-Fe-Ｂ系磁石にクロ
ム酸塩処理を行い、形成したクロメート皮膜が良好な耐
食性を有することが示されている。また特開平2000-199
074号公報には、ジルコニウム、クロム(III)、バナジウ
ム、タングステン、チタン、マンガン、モリブデン、及
び珪素からなる群より選ばれる少なくとも１種の金属の
イオンを合計量で0.01〜50g/リットル（以後、g/Lと記
す。）含み、かつpHが0.5〜4.0に調整され、更に0.01〜
50g/Lのリン酸イオン及び／または次亜リン酸イオンを
含む希土類・鉄系焼結磁石の沈着型表面処理液が記載さ
れている。2. Description of the Related Art R-Fe which is particularly rustable among rare earth magnets
The surface of a -B-based magnet (R is at least one of rare earth elements including Y) has been coated with various plating and chemical conversion coatings, and has been put to practical use. JP-A-60-63902 discloses a rare earth magnet in which a conversion coating and a resin layer are sequentially laminated on the surface of an R-Fe-B magnet to improve oxidation resistance. Example 1 of this publication discloses that a chromate film formed by subjecting an R-Fe-B magnet to chromate treatment has good corrosion resistance. Also, JP-A-2000-199
No. 074 discloses that a total amount of ions of at least one metal selected from the group consisting of zirconium, chromium (III), vanadium, tungsten, titanium, manganese, molybdenum, and silicon is 0.01 to 50 g / liter (hereinafter, referred to as g / L)) and the pH is adjusted to 0.5-4.0,
A deposition type surface treatment liquid for rare earth / iron based sintered magnets containing 50 g / L of phosphate ions and / or hypophosphite ions is described.
【０００３】[0003]
【発明が解決しようとする課題】しかし、特開昭60-639
02号公報に記載のクロメート皮膜は人体に有害な６価ク
ロムを含有するという問題があり、欧州では2003年から
６価クロムの規制が行われようとしている。次に、特開
平2000-199074号公報にはクロムを含有せずにMoとPとの
モル比[Mo/P]を所定値に調整するとともに、所定量のピ
ロリン酸塩及び過酸化水素を添加して構成したR-T-B系
磁石用化成処理液に関する記載はなく、示唆も認められ
ない。このように、クロムを含有せずに、従来のクロメ
ート皮膜を代替できる新規な化成皮膜を有するR-T-B系
磁石の皮膜形成方法が求められていた。SUMMARY OF THE INVENTION However, Japanese Patent Application Laid-Open No. Sho 60-639
The chromate film described in Japanese Patent Publication No. 02 has a problem of containing hexavalent chromium which is harmful to the human body, and regulation of hexavalent chromium is about to be enforced in Europe in 2003. Next, JP-A-2000-199074 discloses that the molar ratio of Mo and P [Mo / P] is adjusted to a predetermined value without containing chromium, and a predetermined amount of pyrophosphate and hydrogen peroxide are added. There is no description of the RTB-based chemical conversion treatment solution for magnets, and no suggestion is found. Thus, there has been a need for a method for forming a RTB-based magnet film having a new chemical conversion film that can replace the conventional chromate film without containing chromium.
【０００４】従って本発明が解決しようとする課題は、
クロムを含有しない新規な化成皮膜を有するR-T-B系磁
石の皮膜形成方法を提供することである。[0004] Therefore, the problem to be solved by the present invention is:
An object of the present invention is to provide a method for forming a film of an RTB magnet having a novel chemical conversion film containing no chromium.
【０００５】[0005]
【課題を解決するための手段】上記課題を解決した本発
明のR-T-B系磁石の皮膜形成方法は、MoとPのモル比［Mo
/P］が１〜30であり、ピロリン酸塩を0.03〜３g/リットル及
び過酸化水素を0.05〜３ミリリットル/リットル含有する化成処理
液によりR2T14B金属間化合物（ＲはＹを含む希土類元素
の少なくとも１種であり、ＴはFeまたはFe及びCoであ
る。）を主相とするR-T-B系磁石体を化成処理すること
を特徴とする。前記化成処理液のpHを４以下に調整する
ことにより良好な耐食性及び熱減磁抵抗性を有する化成
皮膜を形成することができる。また、前処理としてpHが
9〜13.5のアルカリ水溶液による脱脂処理し、次いでpH
が1〜5の酸性溶液によるエッチング処理を行うことで表
面清浄性を良好にすることが可能であり、樹脂との密着
性が良好になる。前記方法によりR-T-B系磁石体に化成
皮膜を被覆し、次いで樹脂（特にエポキシ樹脂、ポリパ
ラキシリレン樹脂または塩素化ポリパラキシリレン樹
脂。）を被覆すると耐食性及び熱減磁抵抗性が向上する
ので実用性に富む。Means for Solving the Problems The method for forming a film of an RTB magnet according to the present invention, which has solved the above-mentioned problems, uses a molar ratio of Mo to P [Mo
/ P] is 1 to 30 and a chemical conversion treatment solution containing 0.03 to 3 g / liter of pyrophosphate and 0.05 to 3 ml / liter of hydrogen peroxide is used to prepare an R 2 T 14 B intermetallic compound (R includes Y A chemical conversion treatment is performed on an RTB-based magnet having at least one rare earth element and T being Fe or Fe and Co) as a main phase. By adjusting the pH of the chemical conversion treatment solution to 4 or less, a chemical conversion film having good corrosion resistance and thermal demagnetization resistance can be formed. As a pretreatment, pH
Degreasing with an alkaline aqueous solution of 9 to 13.5, then pH
However, by performing an etching treatment with an acidic solution of 1 to 5, it is possible to improve the surface cleanliness and improve the adhesion to the resin. If the RTB-based magnet body is coated with a chemical conversion film by the above method, and then coated with a resin (particularly an epoxy resin, polyparaxylylene resin or chlorinated polyparaxylylene resin), the corrosion resistance and the heat demagnetization resistance are improved. Practical.
【０００６】本発明の皮膜形成方法を適用して得られる
R-T-B系磁石の化成皮膜はピロリン酸、Rの水酸化物及び
Moの酸化物を含むものである。通常Mo酸化物は非晶質の
MoO 2からなる。前記化成被膜の上にカップリング剤の皮
膜を被覆し、カップリング剤の皮膜の上に更に樹脂（特
にエポキシ樹脂、ポリパラキシリレン樹脂または塩素化
ポリパラキシリレン樹脂。）を被覆すると耐食性及び熱
減磁抵抗性がより向上する。It is obtained by applying the film forming method of the present invention.
The conversion coating of the R-T-B magnet is pyrophosphoric acid, R hydroxide and
It contains oxides of Mo. Mo oxide is usually amorphous
MoO TwoConsists of Coating agent coating on the conversion coating
After coating the film, add resin (special) on the coupling agent film.
To epoxy resin, polyparaxylylene resin or chlorinated
Polyparaxylylene resin. ) Coating and corrosion resistance and heat
The demagnetization resistance is further improved.
【０００７】本発明に使用する化成処理液の主成分はモ
リブドリン酸イオンであり、副成分のモリブデン酸イオ
ン、リン酸イオン、及びアルカリ金属イオン（アルカリ
土金属イオン）が主成分のモリブドリン酸イオンと平衡
して存在する。[0007] The main component of the chemical conversion treatment solution used in the present invention is molybdophosphate ions, and molybdate phosphate ions, phosphate ions, and molybdophosphate ions of which main components are alkali metal ions (alkaline earth metal ions). Exist in equilibrium.
【０００８】[0008]
【発明の実施の形態】［R-T-B系磁石体］本発明の皮膜
形成方法を適用するR-T-B系磁石体の組成限定理由を以
下に説明する。以下、単に％と記してあるのは重量％を
意味する。R-T-B系磁石体は、主要成分のRとBとTの総計
を100％として、R：27〜34％、B：0.5〜2％、及び残部T
からなり、R2T14B金属間化合物を主相とするものであ
る。またR-T-B系磁石体の総重量を100％としたとき、不
可避的不純物成分として0.6％以下、好ましくは0.3％以
下、より好ましくは0.2％以下の酸素の含有が許容さ
れ、0.2％以下、好ましくは0.1％以下の炭素の含有が許
容され、0.08％以下、好ましくは0.03％以下の窒素の含
有が許容され、0.02％以下、好ましくは0.01％以下の水
素の含有が許容され、0.2％以下、好ましくは0.05％以
下、より好ましくは0.02％以下のCaの含有が許容され
る。Rとして（Nd、Dy）又はPr又は（Pr、Dy）又は（N
d、Dy、Pr）が実用上選択される。R量は27〜34％とする
のが好ましく、29〜32％とするのがより好ましい。Rが2
7％未満では固有保磁力iHcが大きく低下し、34％を超え
ると残留磁束密度Brが大きく低下する。B量は0.5〜2％
とするのが好ましく、0.8〜1.5％とするのがより好まし
い。B量が0.5％未満では実用に耐えるiHcを得られず、2
％超ではBrが大きく低下する。磁気特性を改善するため
に、残部Tの一部をNb、Al、Ga及びCuからなる群から選
択される少なくとも１種の元素により置換するのが好ま
しい。Nb含有量は0.1〜2％とするのが好ましい。Nbの添
加により焼結過程でNbのホウ化物が生成し、結晶粒の異
常粒成長が抑制される。しかしNb含有量が0.1％未満で
は添加効果を得られず、２％超ではNbのホウ化物の生成
量が多くなりBrが大きく低下する。Al含有量は0.02〜2
％とするのが好ましい。Al含有量が0.02％未満では保磁
力及び耐酸化性の向上効果を得られず、2％超ではBrが
急激に低下する。Ga含有量は0.01〜0.5％とするのが好
ましい。Ga含有量が0.01％未満ではiHcの向上効果を得
られず、0.5％超ではBrの低下が顕著になる。Cu含有量
は0.01〜1％とするのが好ましい。Cuの微量添加はiHcの
向上をもたらすが、Cu含有量が1％を超えると添加効果
は飽和し、Cu含有量が0.01％未満では添加効果を得られ
ない。またCo含有量は0.3〜5％とするのが好ましい。Co
含有量が0.3％未満ではキュリー点及び耐食性を向上す
る効果を得られず、5％超ではBr及びiHcが大きく低下す
る。BEST MODE FOR CARRYING OUT THE INVENTION [RTB Magnet] The reason for limiting the composition of an RTB magnet to which the film forming method of the present invention is applied will be described below. Hereinafter, what is simply described as% means% by weight. RTB-based magnets have R: 27 to 34%, B: 0.5 to 2%, and T
And the main phase is an R 2 T 14 B intermetallic compound. When the total weight of the RTB-based magnet body is 100%, oxygen content of 0.6% or less, preferably 0.3% or less, more preferably 0.2% or less is allowed as an inevitable impurity component, and 0.2% or less, preferably 0.2% or less. 0.1% or less of carbon is allowed, 0.08% or less, preferably 0.03% or less of nitrogen is allowed, 0.02% or less, preferably 0.01% or less of hydrogen is allowed, 0.2% or less, preferably Is allowed to contain 0.05% or less, more preferably 0.02% or less of Ca. R is (Nd, Dy) or Pr or (Pr, Dy) or (N
d, Dy, Pr) are practically selected. The R amount is preferably from 27 to 34%, more preferably from 29 to 32%. R is 2
If it is less than 7%, the intrinsic coercive force iHc is greatly reduced, and if it is more than 34%, the residual magnetic flux density Br is greatly reduced. B amount is 0.5-2%
, And more preferably 0.8 to 1.5%. If the B content is less than 0.5%, iHc for practical use cannot be obtained.
%, The Br is greatly reduced. In order to improve the magnetic properties, it is preferable to replace a part of the remaining T with at least one element selected from the group consisting of Nb, Al, Ga and Cu. The Nb content is preferably set to 0.1 to 2%. By adding Nb, a boride of Nb is generated during the sintering process, and abnormal grain growth of crystal grains is suppressed. However, if the Nb content is less than 0.1%, the effect of addition cannot be obtained. Al content is 0.02 ~ 2
% Is preferable. If the Al content is less than 0.02%, the effect of improving the coercive force and oxidation resistance cannot be obtained, and if it exceeds 2%, the Br sharply decreases. The Ga content is preferably 0.01 to 0.5%. If the Ga content is less than 0.01%, the effect of improving iHc cannot be obtained, and if it exceeds 0.5%, the decrease in Br becomes significant. The Cu content is preferably set to 0.01 to 1%. Addition of a small amount of Cu improves iHc, but the addition effect is saturated when the Cu content exceeds 1%, and the addition effect cannot be obtained when the Cu content is less than 0.01%. Further, the Co content is preferably set to 0.3 to 5%. Co
If the content is less than 0.3%, the effect of improving the Curie point and corrosion resistance cannot be obtained, and if it exceeds 5%, Br and iHc are greatly reduced.
【０００９】［前処理及び前処理条件］密着性及び耐食
性に優れた化成皮膜を得るために、化成処理に供するR-
T-B系磁石体の表面を清浄にしておく必要がある。所定
形状に形成したR-T-B系磁石素材表面の付着物（油等）
を除去するために例えば所定量の界面活性剤入りの水溶
液に浸漬して清浄化する。浸漬時に超音波洗浄を併用す
るのが好ましい。次いでpH＝9〜13.5のアルカリ水溶液
中に浸漬して前処理を行う。この場合は磁力劣化を伴わ
ずに表面が良好に脱脂された状態になる。その後pH＝1
〜5の酸性水溶液に浸漬して表面を軽度にエッチングす
る前処理を行う。次いで化成処理を行うと良好な耐食性
及び熱減磁抵抗性を有する化成皮膜を形成したR-T-B系
磁石を得られる。前記前処理液を用いると磁力劣化を抑
制できる理由はR-T-B系磁石体からのR成分等の溶出が抑
制されるからである。前処理用のアルカリ水溶液のpHが
9未満では脱脂効果が十分でなく、pHを13.5超にしても
脱脂効果は飽和しておりコスト高を招く。pH＝9〜13.5
の前処理用アルカリ水溶液は例えばアルカリ金属の水酸
化物（NaOH等）または炭酸塩（Na2CO3等）の所定量を水
に溶解して作製できる。前処理用酸性水溶液は例えば酢
酸、硝酸、硫酸、リン酸、カルボン酸などが使用でき
る。pHが5以上の酸性溶液では化成処理用に好適なエッ
チング状態が得られず、1以下では添加効果が飽和す
る。前処理は通常室温の浸漬処理によるのが好ましい。
浸漬時間は特に限定されないが工業生産上0.5〜60分間
とするのが好ましく、１〜５分間とするのがより好まし
い。浸漬後は前処理液を切り、次いで十分に水洗して次
工程（化成処理）に供する。[Pre-treatment and pre-treatment conditions] In order to obtain a chemical conversion film having excellent adhesion and corrosion resistance, the R-form to be subjected to the chemical conversion treatment is used.
It is necessary to keep the surface of the TB magnet body clean. Deposits (oil, etc.) on the surface of the RTB magnet material formed into a predetermined shape
In order to remove, for example, it is immersed in an aqueous solution containing a predetermined amount of a surfactant to be cleaned. It is preferable to use ultrasonic cleaning at the time of immersion. Next, it is immersed in an alkaline aqueous solution having a pH of 9 to 13.5 to perform a pretreatment. In this case, the surface is satisfactorily degreased without magnetic deterioration. Then pH = 1
A pretreatment of immersing in an acidic aqueous solution of ~ 5 to slightly etch the surface is performed. Then, when a chemical conversion treatment is performed, an RTB-based magnet on which a chemical conversion film having good corrosion resistance and thermal demagnetization resistance is formed can be obtained. The reason why the use of the pretreatment liquid can suppress the magnetic force deterioration is because elution of the R component and the like from the RTB-based magnet body is suppressed. PH of alkaline aqueous solution for pretreatment
If it is less than 9, the degreasing effect is not sufficient, and even if the pH exceeds 13.5, the degreasing effect is saturated and the cost is increased. pH = 9 to 13.5
The pretreatment alkaline aqueous solution can be prepared by dissolving a predetermined amount of an alkali metal hydroxide (eg, NaOH) or carbonate (eg, Na 2 CO 3 ) in water. As the acidic aqueous solution for pretreatment, for example, acetic acid, nitric acid, sulfuric acid, phosphoric acid, carboxylic acid and the like can be used. With an acidic solution having a pH of 5 or more, an etching state suitable for chemical conversion treatment cannot be obtained. It is preferable that the pretreatment is usually performed by immersion treatment at room temperature.
The immersion time is not particularly limited, but is preferably 0.5 to 60 minutes, more preferably 1 to 5 minutes, for industrial production. After the immersion, the pretreatment liquid is cut off and then sufficiently washed with water to be subjected to the next step (chemical conversion treatment).
【００１０】［化成処理液］本発明に用いる化成処理液
はMoとPのモル比［Mo/P］が１〜30であり、ピロリン酸
塩を0.03〜３g/リットル及び過酸化水素を0.05〜３ミリリットル/リ
ットル含有する。モル比［Mo/P］は１〜30に調整される。
モル比［Mo/P］が１未満及び30超では耐食性及び熱減磁
抵抗性に富む化成皮膜を形成するのが困難になる。モル
比［Mo/P］は２〜20とするのが好ましく、３〜12とする
のが特に好ましい。前記化成処理液は例えば純水に対し
てモリブデン酸化合物を1.5〜20g/L、リン酸塩（リン酸
ニ水素ナトリウム等）を0.05〜0.6g/L、ピロリン酸塩を
0.03〜３g/L、及び過酸化水素を0.05〜３mL/L添加する
ことにより作製できる。モリブデン酸化合物は1.5〜20g
/L添加される。モリブデン酸化合物の添加量が1.5g/L未
満及び20g/L超では耐食性及び熱減磁抵抗性が大きく低
下する。モリブデン酸化合物の添加量は３〜10g/Lとす
るのが好ましい。リン酸塩は0.05〜0.6g/L添加される。
リン酸塩の添加量が0.05g/L未満及び0.6g/L超では耐食
性及び熱減磁抵抗性に富む化成皮膜の形成が困難にな
る。リン酸塩の添加量は0.1〜0.3g/Lとするのが好まし
い。ピロリン酸塩は0.03〜３g/L添加される。ピロリン
酸塩の添加量が0.03g/L未満及び３g/L超では耐食性及び
熱減磁抵抗性に富む化成皮膜の形成が困難になる。ピロ
リン酸塩の添加量は0.1〜１g/Lとするのが好ましい。過
酸化水素は0.05〜３mL/L添加される。過酸化水素の添加
量が0.05mL/L未満及び３mL/L超では耐食性及び熱減磁抵
抗性に富む化成皮膜の形成が困難になる。過酸化水素の
添加量は0.5〜１mL/Lとするのが好ましい。化成処理液
のpHは４以下に調整される。pHが４超では耐食性及び熱
減磁抵抗性が大きく低下する。pHは1.0〜4.0とするのが
好ましく、1.5〜3.5とするのがさらに好ましい。[Chemical Conversion Treatment Solution] The chemical conversion treatment solution used in the present invention has a molar ratio of Mo to P [Mo / P] of 1 to 30, a pyrophosphate of 0.03 to 3 g / liter and a hydrogen peroxide of 0.05 to 3 g / liter. Contains 3 ml / liter. The molar ratio [Mo / P] is adjusted to 1 to 30.
If the molar ratio [Mo / P] is less than 1 or more than 30, it becomes difficult to form a chemical conversion film rich in corrosion resistance and thermal demagnetization resistance. The molar ratio [Mo / P] is preferably from 2 to 20, and particularly preferably from 3 to 12. The chemical conversion treatment solution is, for example, 1.5 to 20 g / L of a molybdate compound, 0.05 to 0.6 g / L of a phosphate (such as sodium dihydrogen phosphate), and pyrophosphate in pure water.
It can be prepared by adding 0.03 to 3 g / L and 0.05 to 3 mL / L of hydrogen peroxide. 1.5 to 20 g of molybdate compound
/ L is added. When the addition amount of the molybdate compound is less than 1.5 g / L or more than 20 g / L, the corrosion resistance and the thermal demagnetization resistance are significantly reduced. It is preferable that the addition amount of the molybdate compound is 3 to 10 g / L. Phosphate is added at 0.05-0.6 g / L.
If the added amount of the phosphate is less than 0.05 g / L or more than 0.6 g / L, it becomes difficult to form a chemical conversion film rich in corrosion resistance and thermal demagnetization resistance. It is preferable that the addition amount of the phosphate be 0.1 to 0.3 g / L. Pyrophosphate is added in an amount of 0.03 to 3 g / L. If the addition amount of the pyrophosphate is less than 0.03 g / L or more than 3 g / L, it becomes difficult to form a chemical conversion film rich in corrosion resistance and thermal demagnetization resistance. The addition amount of the pyrophosphate is preferably 0.1 to 1 g / L. Hydrogen peroxide is added at 0.05 to 3 mL / L. If the addition amount of hydrogen peroxide is less than 0.05 mL / L or more than 3 mL / L, it becomes difficult to form a chemical conversion film rich in corrosion resistance and thermal demagnetization resistance. The amount of hydrogen peroxide added is preferably 0.5 to 1 mL / L. The pH of the chemical conversion treatment solution is adjusted to 4 or less. If the pH is more than 4, corrosion resistance and thermal demagnetization resistance are greatly reduced. The pH is preferably 1.0 to 4.0, more preferably 1.5 to 3.5.
【００１１】［化成処理条件］R-T-B系磁石体に対し、
浸漬法、スプレー法、ブラッシング法、ローラーコーテ
ィング法、スチ−ムガン法、T.F.S.法（トリクロールエ
チレン金属表面処理法）、ブラスト法またはワンブース
法等の公知の化成処理方法を適用できるが、浸漬法によ
るのが実用的である。浸漬法の場合、化成処理浴温を5
〜70℃にするのが好ましく、20〜60℃にするのがより好
ましい。これは5℃未満では化成皮膜形成反応が顕著に
遅くなり、また浴中に沈殿を生じて化成処理液の組成ず
れを招来するからである。浴温が70℃超では化成処理液
の蒸発が顕著になり、液管理が煩雑になる。化成処理の
浸漬時間は３〜60分間とするのが好ましく、5〜15分間
とするのがより好ましい。浸漬時間が３分間未満では化
成皮膜を事実上被覆できず、60分間超では化成皮膜の厚
みが飽和する。良好な耐食性、密着性及び熱減磁抵抗性
を付与するために本発明の方法により形成される化成皮
膜の厚み（平均値）は5〜100nmにするのが好ましく、20
〜80nmとするのがさらに好ましい。[Chemical conversion treatment conditions]
Known chemical conversion treatment methods such as an immersion method, a spray method, a brushing method, a roller coating method, a steam gun method, a TFS method (trichlethylene metal surface treatment method), a blast method or a one-booth method can be applied. Is practical. In the case of the immersion method, the
The temperature is preferably set to 7070 ° C., more preferably 20 to 60 ° C. This is because if it is lower than 5 ° C., the chemical conversion film forming reaction is remarkably slowed down, and precipitation occurs in the bath to cause a composition shift of the chemical conversion treatment solution. When the bath temperature exceeds 70 ° C., the chemical conversion treatment liquid evaporates remarkably, and the liquid management becomes complicated. The immersion time of the chemical conversion treatment is preferably from 3 to 60 minutes, more preferably from 5 to 15 minutes. If the immersion time is less than 3 minutes, the chemical conversion film cannot be practically coated, and if it exceeds 60 minutes, the thickness of the chemical conversion film is saturated. The thickness (average value) of the chemical conversion film formed by the method of the present invention is preferably 5 to 100 nm in order to provide good corrosion resistance, adhesion and thermal demagnetization resistance.
More preferably, it is set to 〜80 nm.
【００１２】モリブデン酸化合物としてモリブデン酸塩
が好ましく、モリブデン酸ナトリウム（Na２MoＯ４・2H
２O）が特に好ましい。リン酸塩としてリン酸ナトリウ
ムが好ましく、リン酸ニ水素ナトリウム（NaH ２PO４）
が特に好ましい。ピロリン酸塩としてピロリン酸カリウ
ム（K4P2O7）が好ましい。過酸化水素は市販の過酸化水
素水（過酸化水素濃度が30体積％の希釈水溶液、商品
名：オキシドール）を用いるのが実用的である。化成処
理液に含有されるモリブドリン酸として以下のものが挙
げられる。リンには酸化状態の違いにより、ホスフィン
（-3）、ジホスフィン（-2）、単体（0；黄リン、赤リ
ン、黒リン）、ホスフィン酸（+1；HPH2O2）、ホスホン
酸（+3；H2PHO2）、次リン酸（+4；(HO)2OP-PO(O
H)2）、オルトリン酸（+5；H3PO4）がある。モリブドリ
ン酸はこのうちオルトリン酸、またはホスホン酸が強酸
性溶液中でモリブデン酸と結合したものである。ホスホ
ン酸の場合はM4[P2Mo12O41]・nH2O（M=Li、Na、K、N
H4、CN3H6など）または2M2O・P2O3・5MoO3・nH2O（M=N
a、K、NH4など）となる。オルトリン酸の場合は、12モ
リブドリン酸塩（M3[PO4Mo12O36]）、11モリブドリン酸
塩（M7[PMo11O39]）、5モリブド2リン酸塩（M6P2Mo
5O21）、18モリブド2リン酸塩（M6[(PO4Mo9O27)2]）、1
7モリブド2リン酸塩（M10[P2Mo17O61]）のいずれかとな
る。12モリブドリン酸はアルカリ処理することにより11
モリブドリン酸塩となり、更にアルカリ処理またはリン
酸塩による処理を行うと5モリブド2リン酸塩となる。逆
に11モリブドリン酸を強酸によって処理すると12モリブ
ドリン酸となる。このように、オルトリン酸に関するモ
リブドリン酸には、モリブデン含有量の違いによって12
モリブドリン酸塩、11モリブドリン酸塩、18モリブド2
リン酸塩などがあり、これらのうち12モリブドリン酸塩
あるいは12モリブドリン酸・n水和物を用いるのが耐食
性を高めるために好ましい。なお前記化学式中のnはい
ずれも正の整数である。Molybdate as a molybdate compound
Preferably, sodium molybdate (Na2MoO4・ 2H
2O) is particularly preferred. Sodium phosphate as phosphate
And sodium dihydrogen phosphate (NaH 2PO4)
Is particularly preferred. Potassium pyrophosphate as pyrophosphate
(KFourPTwoO7Is preferred. Hydrogen peroxide is commercially available water peroxide
Raw water (diluted aqueous solution with a hydrogen peroxide concentration of 30% by volume, product
It is practical to use (name: oxidol). Chemical process
The following are listed as molybdophosphoric acid contained in the physiological fluid.
I can do it. Phosphine depends on the oxidation state of phosphorus.
(-3), diphosphine (-2), simple substance (0; yellow phosphorus, red
, Black phosphorus), phosphinic acid (+1; HPHTwoOTwo), Phosphon
Acid (+3; HTwoPHOTwo), Hypophosphoric acid (+4; (HO)TwoOP-PO (O
H)Two), Orthophosphoric acid (+5; HThreePOFour). Molybdenum
Of these, orthophosphoric acid or phosphonic acid is a strong acid
It binds to molybdic acid in a neutral solution. Phospho
M for acidFour[PTwoMo12O41] ・ NHTwoO (M = Li, Na, K, N
HFour, CNThreeH6Etc.) or 2MTwoO ・ PTwoOThree・ 5MoOThree・ NHTwoO (M = N
a, K, NHFourEtc.). For orthophosphoric acid, 12
Ribdophosphate (MThree[POFourMo12O36]), 11 molybdophosphoric acid
Salt (M7[PMo11O39]), 5 molybdo diphosphate (M6PTwoMo
FiveOtwenty one), 18 molybdo diphosphate (M6[(POFourMo9O27)Two]), 1
7 Molybdo diphosphate (MTen[PTwoMo17O61])
You. 12 Molybdophosphoric acid is treated with alkali
Molybdophosphate and further alkali treatment or phosphorus
Treatment with acid salts results in 5-molybdo diphosphate. Reverse
11 molybdophosphoric acid treated with strong acid
It becomes doric acid. Thus, the model for orthophosphoric acid
There are 12 molybdenum contents depending on the molybdenum content.
Molybdophosphate, 11 molybdophosphate, 18 molybdo2
Phosphate and the like, of which 12 molybdophosphate
Or use of 12 molybdophosphoric acid n-hydrate is corrosion resistant
It is preferable to enhance the properties. N in the above chemical formula
The shift is also a positive integer.
【００１３】本発明により作製した化成皮膜被覆R-T-B
磁石の表面に更に樹脂を被覆し実用に供するが、この被
覆樹脂として公知の熱可塑性樹脂（ポリアミド樹脂また
はポリパラキシリレン樹脂等）または熱硬化性樹脂（エ
ポキシ樹脂等）を用いることができる。リサイクルを優
先する場合は熱可塑性樹脂が適し、耐熱性を重視する場
合は熱硬化性樹脂が適する。特にポリパラキシリレン樹
脂または塩素化ポリパラキシリレン樹脂の皮膜はピンホ
ールが少なく、ガス及び水蒸気透過性が極めて低いので
好ましい。ポリパラキシリレン樹脂または塩素化ポリパ
ラキシリレン樹脂として、米国ユニオン・カーバイド社
製の、商品名がパリレンN（ポリパラキシリレン）、パ
リレンC（ポリモノクロロパラキシリレン）またはパリ
レンD（ポリジクロロパラキシリレン）が挙げられる。
樹脂の被覆方法は電着法、吹き付け法、塗布法、浸漬
法、真空蒸着法、またはプラズマ重合法等の公知の方法
を採用できるが、電着法または真空蒸着法が実用性に富
む。良好な耐食性を付与するために、樹脂の被覆厚み
（平均値）を0.5〜30μmにするのが好ましく、5〜20μm
にするのがより好ましい。樹脂の被覆厚みが0.5μm未満
では耐食性の向上効果が実質的に得られず、30μm超で
は非磁性の樹脂皮膜の厚み増加により所定の磁石応用製
品に組み込んだときの磁気ギャップの磁束密度分布の低
下を無視できなくなる。The chemical conversion coating-coated RTB prepared according to the present invention
The surface of the magnet is further coated with a resin for practical use. As the coating resin, a known thermoplastic resin (eg, polyamide resin or polyparaxylylene resin) or a thermosetting resin (eg, epoxy resin) can be used. When priority is given to recycling, a thermoplastic resin is suitable. When importance is placed on heat resistance, a thermosetting resin is suitable. In particular, a film of polyparaxylylene resin or chlorinated polyparaxylylene resin is preferable because it has few pinholes and has extremely low gas and water vapor permeability. As polyparaxylylene resin or chlorinated polyparaxylylene resin, trade names of Parylene N (polyparaxylylene), Parylene C (polymonochloroparaxylylene) or Parylene D (polydichloro) manufactured by Union Carbide, USA Paraxylylene).
Known methods such as an electrodeposition method, a spraying method, a coating method, an immersion method, a vacuum evaporation method, and a plasma polymerization method can be adopted as the resin coating method, but the electrodeposition method or the vacuum evaporation method is more practical. In order to provide good corrosion resistance, the resin coating thickness (average value) is preferably 0.5 to 30 μm, and 5 to 20 μm
Is more preferable. When the resin coating thickness is less than 0.5 μm, the effect of improving corrosion resistance is not substantially obtained, and when it exceeds 30 μm, the thickness of the non-magnetic resin film increases and the magnetic flux density distribution of the magnetic gap when incorporated in a given magnet application product is increased. The decline cannot be ignored.
【００１４】カップリング剤として、イソプロピルトリ
イソステアロイルチタネート、イソプロピルトリ（Ｎ−
アミノエチル−アミノエチル）チタネート、イソプロピ
ルトリス（ジオクチルパイロホスフェート）チタネー
ト、またはイソプロピルトリオクタノイルチタネート等
のチタネート系カップリング剤が挙げられる。またγ−
アミノプロピルトリエトキシシラン、Ｎ−β−（アミノ
エチル）−γ−アミノプロピルトリメトキシシラン、γ
−グリシドキシ−プロピルトリメトキシシラン、β−
（３，４−エポキシ−シクロヘキシル）エチルトリメト
キシシラン、ビニルトリエトキシシラン、ビニルトリメ
トキシシラン、ビニル−トリス（２−メトキシエトキ
シ）シラン、ジフェニルジメトキシシラン、γ―メタア
クリロキシプロピルトリメトキシシラン、3−クロロプ
ロピルトリメトキシシラン、または3−メルカプトプロ
ピルトリメトキシシラン等のシラン系カップリング剤が
挙げられる。またアセトアルコキシアルミニウムジイソ
プロピレートのようなアルミニウム系、ジルコニウム
系、鉄系、または錫系のカップリング剤が挙げられる。
化成皮膜被覆R-T-B系磁石をカップリング剤により表面
処理する方法は2通りある。 (1)化成皮膜被覆R-T-B系磁
石の総表面積の1〜5倍に相当するカップリング剤の添加
量を、カップリング剤の最小被覆面積から換算して求め
る。次いで所定量のシランカップリング剤を溶媒（エタ
ノール等）により希釈し、この希釈溶液に化成皮膜被覆
R-T-B系磁石を浸漬し、次いで真空ポンプで排気しなが
ら約50〜80℃に加熱し溶媒を蒸発させる。次いで冷却す
れば化成皮膜上にカップリング剤の皮膜を被覆できる。
(2)カップリング剤0.05〜5重量部と被覆樹脂99.95〜95
重量部とをミキサーにより混合し、得られた混合物を化
成皮膜被覆R-T-B系磁石に被覆すると化成皮膜と樹脂皮
膜との界面にカップリング剤の皮膜が形成される。As coupling agents, isopropyl triisostearoyl titanate, isopropyl tri (N-
Titanate-based coupling agents such as aminoethyl-aminoethyl) titanate, isopropyl tris (dioctyl pyrophosphate) titanate, and isopropyl trioctanoyl titanate. Also, γ-
Aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, γ
-Glycidoxy-propyltrimethoxysilane, β-
(3,4-epoxy-cyclohexyl) ethyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyl-tris (2-methoxyethoxy) silane, diphenyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, 3 And silane coupling agents such as -chloropropyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane. Further, an aluminum-based, zirconium-based, iron-based, or tin-based coupling agent such as acetoalkoxyaluminum diisopropylate may be used.
There are two methods for surface-treating a chemical conversion film coated RTB magnet with a coupling agent. (1) The addition amount of the coupling agent corresponding to 1 to 5 times the total surface area of the RTB magnet coated with the chemical conversion film is determined by converting from the minimum coating area of the coupling agent. Next, a predetermined amount of the silane coupling agent is diluted with a solvent (such as ethanol), and the diluted solution is coated with a chemical conversion coating.
The RTB magnet is immersed, and then heated to about 50 to 80 ° C. while evacuating with a vacuum pump to evaporate the solvent. Then, when cooled, a coating of a coupling agent can be coated on the chemical conversion coating.
(2) 0.05 to 5 parts by weight of coupling agent and 99.95 to 95 of coating resin
When the resulting mixture is mixed with a conversion coating RTB-based magnet, a coating of a coupling agent is formed at the interface between the conversion coating and the resin coating.
【００１５】本発明の皮膜形成方法を適用する好ましい
R-T-B系磁石として、ラジアル異方性、極異方性または
径２極異方性を有するリング磁石、外径5〜50mm、内径2
〜30mm、軸方向長さ（厚み）が0.5〜2 mmの扁平リング
磁石（厚み方向が異方性方向。）、及びCDまたはDVD等
のピックアップ装置のアクチュエータに組み込まれる縦
2.0〜6.0 mm、横2.0〜6.0 mm、及び厚さ0.4〜3 mmの薄
肉板状磁石（厚み方向が異方性方向。）が挙げられる。It is preferable to apply the film forming method of the present invention.
Ring magnets with radial anisotropy, polar anisotropy or dipole anisotropy as RTB magnets, outer diameter 5-50 mm, inner diameter 2
Up to 30 mm, flat ring magnet with an axial length (thickness) of 0.5 to 2 mm (thickness direction is anisotropic direction), and vertical incorporated in actuator of pickup device such as CD or DVD
A thin plate-shaped magnet having a thickness of 2.0 to 6.0 mm, a width of 2.0 to 6.0 mm, and a thickness of 0.4 to 3 mm (the thickness direction is an anisotropic direction) is exemplified.
【００１６】[0016]
【実施例】以下、実施例により本発明を詳細に説明する
が、それら実施例により本発明が限定されるものではな
い。EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples.
【００１７】（実施例１）Nd：26.81％、Pr：5.04％、D
y：0.62％、Ｂ：1.01％、Co：2.02％、Al：0.06％、G
a：0.11％、Cu：0.12％、Fe：64.21％ の主要成分組成
を有し、縦5mm×横5mm×厚み1mm（厚み方向が異方性方
向。）の矩形薄板状CDピックアップ用R-T-B系焼結磁石
素材を水中で超音波洗浄し、pHが12の水酸化ナトリウム
水溶液にて洗浄した。次にCH3COOHを３重量％含有する
室温の水溶液中に２分間浸漬する前処理を行い、次いで
水洗した。次にモル比[Mo/P]を変化した表１のNo.１〜
３に記載の化成処理液中にそれぞれ60℃×10分間浸漬
し、次いで乾燥した。得られた各化成皮膜被覆R-T-B系
磁石の化成皮膜の厚みをX線光電子分光法(XPS)により、
(株)島津製作所製、型式：ESCA-850を使用し、化成皮膜
の深さ方向の分析から求めた。その結果、No.１〜３の
各化成皮膜被覆R-T-B系磁石に形成された化成皮膜の膜
厚は30〜50nm（平均値）であった。次に各化成皮膜被覆
R-T-B系磁石の表面をSEM-EDX（（株）日立製作所製、型
式：S2300）により分析した結果、化成皮膜は主要構成
成分としてO,P,Nd,Pr及びMoを含み、不可避的不純物と
してC,Cl及びCaを含むことがわかった。次に各化成皮膜
被覆R-T-B系磁石の化成皮膜部分を、薄膜Ｘ線回折装置
（理学電機(株)製、型式：RINT2500V、Cukα1線を使
用。）によりＸ線回折した結果、いずれも化成皮膜の主
要構成相としてピロリン酸（H4P2O7）、Nd(OH)3及びPr
(OH)3を含有することがわかった。次に各化成皮膜被覆R
-T-B系磁石の表面を、ESCA（VG Scientific製、型式：
MICROLAB 310-D）により分析した結果、化成皮膜中のM
oはMoO2の形で存在するのがわかった。以上の解析結果
から、No.１〜３の化成皮膜被覆R-T-B系磁石の化成皮膜
はいずれもピロリン酸、Rの水酸化物、及び非晶質のMoO
2から実質的になることがわかった。次に各化成皮膜被
覆R-T-B系磁石の表面に電着法により平均膜厚20μmのエ
ポキシ樹脂皮膜を被覆した。得られた各化成皮膜/エポ
キシ樹脂皮膜被覆R-T-B系磁石を温度120℃、相対湿度10
0％、圧力２気圧の大気雰囲気中に24時間保持するPCT試
験を行った。室温の大気中に戻したPCT試験後の試料の
外観を目視観察し、膨れが観察されたものを（×）、健
全な外観のものを（○）とし、表１の耐食性で示す。次
に各化成皮膜/エポキシ樹脂皮膜被覆R-T-B系磁石を室温
において総磁束量（Φ1）が飽和する条件で着磁し、Φ1
を測定した。次にΦ1測定後の試料を大気中で85℃で2時
間加熱後室温まで冷却し、総磁束量（Φ2）を測定し
た。得られたΦ1及びΦ2から、下記式により求めた熱減
磁率を表１に示す。 熱減磁率＝［（Φ1−Φ2）／Φ1］×100（％） Φ1：室温において着磁後測定した総磁束量 Φ2：室温において着磁後、大気中で85℃×2時間加熱
し、次いで室温まで冷却後測定した総磁束量(Example 1) Nd: 26.81%, Pr: 5.04%, D
y: 0.62%, B: 1.01%, Co: 2.02%, Al: 0.06%, G
a: 0.11%, Cu: 0.12%, Fe: 64.21%, RTB system for rectangular thin plate CD pickup of 5mm × 5mm × 1mm (thickness direction is anisotropic). The magnet material was ultrasonically washed in water and washed with an aqueous solution of sodium hydroxide having a pH of 12. Next, a pretreatment of immersion in an aqueous solution containing 3% by weight of CH 3 COOH at room temperature for 2 minutes was performed, and then the substrate was washed with water. Next, No. 1 to Table 1 in which the molar ratio [Mo / P] was changed
Each was immersed in the chemical conversion treatment solution described in No. 3 at 60 ° C. for 10 minutes, and then dried. By X-ray photoelectron spectroscopy (XPS), the thickness of the conversion coating of each of the obtained conversion coating RTB-based magnets was determined.
It was obtained from the analysis of the chemical conversion film in the depth direction using Model: ESCA-850 manufactured by Shimadzu Corporation. As a result, the film thickness of the chemical conversion film formed on each of the chemical conversion film-coated RTB magnets of Nos. 1 to 3 was 30 to 50 nm (average value). Next, each chemical conversion coating
As a result of analyzing the surface of the RTB magnet by SEM-EDX (model: S2300, manufactured by Hitachi, Ltd.), the chemical conversion film contains O, P, Nd, Pr, and Mo as main components, and C as an inevitable impurity. , Cl and Ca. Next, the conversion coating portion of each conversion coating-coated RTB magnet was subjected to X-ray diffraction using a thin film X-ray diffractometer (Rigaku Denki Co., Ltd., model: RINT2500V, Cukα1 line). Pyrophosphate (H 4 P 2 O 7 ), Nd (OH) 3 and Pr as main constituent phases
It was found to contain (OH) 3 . Next, each conversion coating R
-Use the surface of the TB magnet with ESCA (VG Scientific, model:
As a result of analysis by MICROLAB 310-D), M
o was found to be in the form of MoO 2 . From the above analysis results, the conversion coatings of the No. 1-3 conversion coating RTB-based magnets were all pyrophosphoric acid, R hydroxide, and amorphous MoO.
It turns out that it becomes substantially from 2 . Next, an epoxy resin film having an average film thickness of 20 μm was coated on the surface of each conversion film-coated RTB magnet by an electrodeposition method. Each of the obtained chemical conversion coating / epoxy resin coating RTB-based magnet was heated at 120 ° C and relative humidity of 10
A PCT test was performed in which the sample was kept in an atmosphere of 0% and a pressure of 2 atm for 24 hours. The appearance of the sample after the PCT test returned to the atmosphere at room temperature was visually observed, and a sample in which swelling was observed was indicated by (x), and a sample having a healthy appearance was indicated by (o). Next, each conversion film / epoxy resin film-coated RTB magnet was magnetized at room temperature under the condition that the total magnetic flux (Φ1) was saturated.
Was measured. Next, the sample after the measurement of Φ1 was heated in the air at 85 ° C. for 2 hours, and then cooled to room temperature, and the total magnetic flux (Φ2) was measured. Table 1 shows the thermal demagnetization rates obtained from the obtained Φ1 and Φ2 according to the following equations. Thermal demagnetization rate = [(Φ1-Φ2) / Φ1] x 100 (%) Φ1: Total magnetic flux measured after magnetization at room temperature Φ2: After magnetization at room temperature, heat in air at 85 ° C for 2 hours, Total magnetic flux measured after cooling to room temperature
【００１８】（比較例１）表１のNo.11,12に記載の各化
成処理液を用いて化成処理した以外は実施例１と同様に
して化成皮膜被覆R-T-B系磁石を作製し、次いで電着法
により平均膜厚20μｍのエポキシ樹脂皮膜を被覆した。
得られた化成皮膜/エポキシ樹脂皮膜被覆R-T-B系磁石の
耐食性及び熱減磁率を評価した結果を表１に示す。Comparative Example 1 A chemical conversion coating-coated RTB magnet was prepared in the same manner as in Example 1 except that the chemical conversion treatment was performed using each of the chemical conversion treatment solutions described in Nos. 11 and 12 in Table 1. An epoxy resin film having an average film thickness of 20 μm was coated by a deposition method.
Table 1 shows the evaluation results of the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet.
【００１９】（従来例１）化成処理液に従来のクロム酸
を用いて化成処理した以外は実施例１と同様にして化成
皮膜被覆R-T-B系磁石を作製し、次いで電着法により平
均膜厚20μｍのエポキシ樹脂皮膜を被覆した。得られた
化成皮膜/エポキシ樹脂皮膜被覆R-T-B系磁石の耐食性及
び熱減磁率を評価した結果を表１に示す。(Conventional Example 1) A chemical conversion coating-coated RTB-based magnet was prepared in the same manner as in Example 1 except that the chemical conversion treatment was carried out using conventional chromic acid, and then the average film thickness was 20 μm by an electrodeposition method. Was coated with an epoxy resin film. Table 1 shows the evaluation results of the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet.
【００２０】[0020]
【表１】 [Table 1]
【００２１】表１より、化成処理液のモル比[Mo/P]が１
〜30を外れると耐食性が悪化し、かつ熱減磁率が従来の
クロメート皮膜/エポキシ樹脂皮膜被覆R-T-B系磁石に比
べて劣ることがわかる。According to Table 1, the molar ratio [Mo / P] of the chemical conversion treatment liquid is 1
It can be seen that if it is out of ~ 30, the corrosion resistance is deteriorated and the thermal demagnetization rate is inferior to that of the conventional chromate film / epoxy resin film-coated RTB magnet.
【００２２】（実施例２）ピロリン酸カリウムの添加量
を変化した化成処理液を作製して化成処理した以外は実
施例１と同様にして化成皮膜被覆R-T-B系磁石を作製し
た。次に電着法により平均膜厚20μｍのエポキシ樹脂皮
膜を被覆した。得られた化成皮膜/エポキシ樹脂皮膜被
覆R-T-B系磁石の耐食性及び熱減磁率を評価した結果を
表２に示す。 （比較例２）表２に記載の化成処理液を用いて化成処理
した以外は実施例１と同様にして化成皮膜被覆R-T-B系
磁石を作製し、次いで電着法により平均膜厚20μｍのエ
ポキシ樹脂皮膜を被覆した。得られた化成皮膜/エポキ
シ樹脂皮膜被覆R-T-B系磁石の耐食性及び熱減磁率を評
価した結果を表２に示す。Example 2 A chemical conversion coating-coated RTB-based magnet was produced in the same manner as in Example 1 except that a chemical conversion treatment solution in which the amount of added potassium pyrophosphate was changed and a chemical conversion treatment was performed. Next, an epoxy resin film having an average thickness of 20 μm was coated by an electrodeposition method. Table 2 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet. (Comparative Example 2) A chemical conversion coating-coated RTB-based magnet was prepared in the same manner as in Example 1 except that the chemical conversion treatment was performed using the chemical conversion treatment solution described in Table 2, and then an epoxy resin having an average film thickness of 20 µm was formed by an electrodeposition method. The coating was coated. Table 2 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet.
【００２３】[0023]
【表２】 [Table 2]
【００２４】表２より、ピロリン酸カリウムの添加量が
0.03〜３g/Lの範囲を外れると耐食性が悪化し、かつ熱
減磁率も悪化するのがわかる。According to Table 2, the amount of potassium pyrophosphate added was
It can be seen that if it is out of the range of 0.03 to 3 g / L, the corrosion resistance deteriorates and the thermal demagnetization rate also deteriorates.
【００２５】（実施例３）過酸化水素の添加量を変化し
た化成処理液を作製し、化成処理した以外は実施例１と
同様にして化成皮膜被覆R-T-B系磁石を作製した。次に
電着法により平均膜厚20μｍのエポキシ樹脂皮膜を被覆
した。得られた化成皮膜/エポキシ樹脂皮膜被覆R-T-B系
磁石の耐食性及び熱減磁率を評価した結果を表３に示
す。 （比較例３）表３に記載の化成処理液を用いて化成処理
した以外は実施例１と同様にして化成皮膜被覆R-T-B系
磁石を作製し、次いで電着法により平均膜厚20μｍのエ
ポキシ樹脂皮膜を被覆した。得られた化成皮膜/エポキ
シ樹脂皮膜被覆R-T-B系磁石の耐食性及び熱減磁率を評
価した結果を表３に示す。Example 3 A chemical conversion coating solution was prepared in the same manner as in Example 1 except that a chemical conversion treatment solution was prepared in which the amount of hydrogen peroxide added was changed, and a chemical conversion treatment was carried out. Next, an epoxy resin film having an average thickness of 20 μm was coated by an electrodeposition method. Table 3 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet. (Comparative Example 3) A chemical conversion coating-coated RTB-based magnet was prepared in the same manner as in Example 1 except that the chemical conversion treatment was performed using the chemical conversion treatment solution described in Table 3, and then an epoxy resin having an average film thickness of 20 µm was formed by electrodeposition. The coating was coated. Table 3 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet.
【００２６】[0026]
【表３】 [Table 3]
【００２７】表３より、過酸化水素の添加量が0.1〜３m
L/Lの範囲を外れると耐食性が悪化するとともに、熱減
磁率が従来のクロメート被覆磁石に比べて劣っているこ
とがわかる。According to Table 3, the amount of hydrogen peroxide added was 0.1 to 3 m.
It can be seen that when the ratio is out of the L / L range, the corrosion resistance deteriorates and the thermal demagnetization rate is inferior to that of the conventional chromate-coated magnet.
【００２８】（実施例４）pHを変化した化成処理液を作
製して化成処理した以外は実施例１と同様にして化成皮
膜被覆R-T-B系磁石を作製した。なお化成処理液のpHの
微調整のために水酸化ナトリウム水溶液または硝酸水溶
液を適量添加した。次に電着法により平均膜厚20μｍの
エポキシ樹脂皮膜を被覆した。得られた化成皮膜/エポ
キシ樹脂皮膜被覆R-T-B系磁石の耐食性及び熱減磁率を
評価した結果を表４に示す。 （比較例４）表４に記載の化成処理液を用いて化成処理
した以外は実施例１と同様にして化成皮膜被覆R-T-B系
磁石を作製し、次いで電着法により平均膜厚20μｍのエ
ポキシ樹脂皮膜を被覆した。得られた化成皮膜/エポキ
シ樹脂皮膜被覆R-T-B系磁石の耐食性及び熱減磁率を評
価した結果を表４に示す。Example 4 A chemical conversion coating-coated RTB-based magnet was prepared in the same manner as in Example 1 except that a chemical conversion treatment solution having a changed pH was prepared and subjected to a chemical conversion treatment. In order to finely adjust the pH of the chemical conversion treatment solution, an appropriate amount of an aqueous sodium hydroxide solution or an aqueous nitric acid solution was added. Next, an epoxy resin film having an average thickness of 20 μm was coated by an electrodeposition method. Table 4 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet. (Comparative Example 4) A chemical conversion coating-coated RTB-based magnet was prepared in the same manner as in Example 1 except that the chemical conversion treatment was performed using the chemical conversion treatment solution shown in Table 4, and then an epoxy resin having an average film thickness of 20 µm was formed by an electrodeposition method. The coating was coated. Table 4 shows the results of evaluating the corrosion resistance and the thermal demagnetization rate of the obtained chemical conversion film / epoxy resin film-coated RTB magnet.
【００２９】[0029]
【表４】 [Table 4]
【００３０】表４より、化成処理液のpHが４超では耐食
性が悪化し、かつ熱減磁率が悪化するのがわかる。From Table 4, it can be seen that when the pH of the chemical conversion treatment liquid is more than 4, the corrosion resistance deteriorates and the thermal demagnetization rate deteriorates.
【００３１】（実施例５）Nd：26.2％、Pr：5.0％、D
y：0.8％、Ｂ：0.97％、Co：3.0％、Al：0.1％、Ga：0.
1％、Cu：0.1％、Fe：63.73％ の主要成分組成を有
し、外径20mm×内径10mm×厚み0.8mm（厚み方向が異方
性方向。）の扁平形状に形成したR-T-B系焼結リング磁
石素材を水中で超音波洗浄し、pHが12の水酸化ナトリウ
ム水溶液にて洗浄した。次に室温のCH3COOHを１重量％
含有する水溶液中に３分間浸漬する前処理を行い、次い
で水洗した。次に実施例１のNo.2の試料と同じ化成処理
を行った。得られた化成皮膜被覆R-T-B系磁石の化成皮
膜の膜厚は45nmであり、かつこの化成皮膜はピロリン
酸、Rの水酸化物、及び非晶質のMoO2から実質的になる
のがわかった。次に前記化成皮膜被覆R-T-B系磁石の総
表面積の1.2倍に相当する量のシラン系カップリング剤
（エポキシ基含有型；３−グリシドキシプロピルトリメ
トキシシラン、最小被覆面積331m2/g）をエタノール30c
cに添加して希釈した表面処理液を作製した。この表面
処理液中に前記化成皮膜被覆R-T-B系磁石を浸漬し、次
いで真空ポンプで排気しながら80℃に加熱してエタノー
ルを蒸発させ、次いで冷却してシラン系カップリング剤
の被膜を形成した。次にこの化成皮膜/シラン系カップ
リング剤皮膜被覆R-T-B系磁石の表面に真空蒸着法によ
り平均膜厚８μmのポリパラキシリレン樹脂を被覆し
た。得られた化成皮膜/シラン系カップリング剤皮膜/ポ
リパラキシリレン樹脂皮膜被覆R-T-B系磁石の耐食性を
実施例１と同様にして評価したところ良好であった。ま
た実施例１と同様にして測定した熱減磁率は3.1％であ
った。 （従来例２）実施例５と同じ扁平形状に形成したR-T-B
系焼結リング磁石素材を水中で超音波洗浄し、pHが12の
水酸化ナトリウム水溶液にて洗浄した。次に室温のCH3C
OOHを１重量％含有する水溶液中に３分間浸漬する前処
理を行い、次いで水洗した。次に化成処理液に従来のク
ロム酸を用いて化成処理を行いクロメート皮膜被覆R-T-
B系磁石を得た。以降は実施例５と同様にしてシラン系
カップリング剤により表面処理し、次いでポリパラキシ
リレン樹脂を被覆した。得られたクロメート皮膜/シラ
ン系カップリング剤皮膜/ポリパラキシリレン樹脂皮膜
被覆R-T-B系磁石の耐食性は実施例５と同等であった
が、熱減磁率は４％であり悪かった。(Example 5) Nd: 26.2%, Pr: 5.0%, D
y: 0.8%, B: 0.97%, Co: 3.0%, Al: 0.1%, Ga: 0.
RTB-based sintering with a main component composition of 1%, Cu: 0.1%, Fe: 63.73%, formed into a flat shape with an outer diameter of 20mm x inner diameter of 10mm x thickness of 0.8mm (thickness direction is anisotropic) The ring magnet material was ultrasonically cleaned in water and then washed with an aqueous solution of sodium hydroxide having a pH of 12. Next, 1% by weight of CH 3 COOH at room temperature
A pretreatment of immersion in the contained aqueous solution for 3 minutes was performed, followed by washing with water. Next, the same chemical conversion treatment as that of the sample No. 2 of Example 1 was performed. The film thickness of the chemical conversion coating of the resulting conversion coating coated RTB magnet is 45 nm, and the conversion coating was found to become pyrophosphate, hydroxides R, and the MoO 2 amorphous substantially . Next, an amount of a silane coupling agent (epoxy group-containing type; 3-glycidoxypropyltrimethoxysilane, minimum coating area: 331 m 2 / g) corresponding to 1.2 times the total surface area of the conversion coating-coated RTB magnet was added. Ethanol 30c
A surface treatment liquid diluted by adding to c was prepared. The conversion coating-coated RTB magnet was immersed in the surface treatment solution, heated to 80 ° C. while evacuating with a vacuum pump to evaporate ethanol, and then cooled to form a silane coupling agent coating. Next, a polyparaxylylene resin having an average film thickness of 8 μm was coated on the surface of the chemical conversion coating / silane-based coupling agent coating-coated RTB magnet by a vacuum evaporation method. The corrosion resistance of the resulting chemical conversion coating / silane-based coupling agent coating / polyparaxylylene resin coating-coated RTB magnet was evaluated in the same manner as in Example 1 and found to be good. The thermal demagnetization rate measured in the same manner as in Example 1 was 3.1%. (Conventional example 2) RTB formed in the same flat shape as in Example 5
The system sintered ring magnet material was subjected to ultrasonic cleaning in water and washed with an aqueous solution of sodium hydroxide having a pH of 12. Then CH 3 C at room temperature
Pretreatment was performed by immersion in an aqueous solution containing 1% by weight of OOH for 3 minutes, followed by washing with water. Next, a chemical conversion treatment was carried out using conventional chromic acid in the chemical conversion treatment solution, and a chromate film-coated RT-
B magnet was obtained. Thereafter, the surface was treated with a silane coupling agent in the same manner as in Example 5, and then coated with a polyparaxylylene resin. The corrosion resistance of the obtained chromate film / silane-based coupling agent film / polyparaxylylene resin film-coated RTB magnet was the same as that of Example 5, but the thermal demagnetization rate was 4%, which was poor.
【００３２】[0032]
【発明の効果】人体や環境に有害なクロムを含有せず
に、耐食性が従来のクロメート皮膜とほぼ同等であり、
熱減磁抵抗性の良好な化成皮膜を有するR-T-B系磁石の
皮膜形成方法を提供することができる。The present invention does not contain chromium which is harmful to the human body and the environment, and has almost the same corrosion resistance as the conventional chromate film.
An RTB-based magnet film formation method having a chemical conversion film having good thermal demagnetization resistance can be provided.
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 4K018 AA27 BA18 DA11 FA25 FA27 KA45 4K026 AA02 BA03 CA13 CA25 CA26 CA29 CA35 EA06 EA08 EB08 4K044 AA02 AB10 BA17 BA21 BB01 BB03 BC02 CA04 CA16 CA53 5E040 AA04 BC01 BC05 CA01 HB14 NN17 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K018 AA27 BA18 DA11 FA25 FA27 KA45 4K026 AA02 BA03 CA13 CA25 CA26 CA29 CA35 EA06 EA08 EB08 4K044 AA02 AB10 BA17 BA21 BB01 BB03 BC02 CA04 CA16 CA53 5E040 AA04 BC01 BC05 CA01
Claims (4)
り、ピロリン酸塩を0.03〜３g/リットル及び過酸化水素を0.
05〜３ミリリットル/リットル含有する化成処理液によりR2T14B金
属間化合物（ＲはＹを含む希土類元素の少なくとも１種
であり、ＴはFeまたはFe及びCoである。）を主相とする
R-T-B系磁石体を化成処理することを特徴とするR-T-B系
磁石の皮膜形成方法。(1) The molar ratio of Mo to P [Mo / P] is 1 to 30, the pyrophosphate is 0.03 to 3 g / liter and the hydrogen peroxide is 0.1 to 0.3 g.
R 2 T 14 B intermetallic compound chemical conversion treatment solution containing 05-3 ml / l (R is at least one of rare earth elements including Y, T is Fe or Fe and Co.) And the main phase Do
A method for forming a film on an RTB-based magnet, comprising subjecting the RTB-based magnet body to a chemical conversion treatment.
る請求項１に記載のR-T-B系磁石の皮膜形成方法。2. The method according to claim 1, wherein a chemical conversion treatment solution whose pH is adjusted to 4 or less is used.
であって、前処理としてpHが9〜13.5のアルカリ水溶液
による脱脂処理し、次いでpHが1〜5の酸性溶液によるエ
ッチング処理を行うことを特徴とするR-T-B系磁石の皮
膜形成方法。3. The method for forming a film according to claim 1, wherein a degreasing treatment with an alkaline aqueous solution having a pH of 9 to 13.5 is performed as a pretreatment, and an etching treatment with an acidic solution having a pH of 1 to 5 is performed. A method for forming a film on an RTB-based magnet.
脂を被覆する請求項１〜３に記載のR-T-B系磁石の皮膜
形成方法。4. The method for forming a film on an RTB magnet according to claim 1, wherein the RTB magnet is subjected to a chemical conversion treatment and then coated with a resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2001354169A JP2002212750A (en) | 2000-11-20 | 2001-11-20 | Film deposition method for r-t-b based magnet |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000-352299 | 2000-11-20 | ||
| JP2000352299 | 2000-11-20 | ||
| JP2001354169A JP2002212750A (en) | 2000-11-20 | 2001-11-20 | Film deposition method for r-t-b based magnet |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2002212750A true JP2002212750A (en) | 2002-07-31 |
Family
ID=26604262
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2001354169A Pending JP2002212750A (en) | 2000-11-20 | 2001-11-20 | Film deposition method for r-t-b based magnet |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2002212750A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006049863A (en) * | 2004-06-30 | 2006-02-16 | Shin Etsu Chem Co Ltd | Corrosion resistant rare earth magnet and manufacturing method thereof |
| JP2006165218A (en) * | 2004-12-07 | 2006-06-22 | Shin Etsu Chem Co Ltd | Rtmb-based rare earth permanent magnet and manufacturing method therefor |
| EP3822996A1 (en) * | 2019-11-12 | 2021-05-19 | Abiomed Europe GmbH | Corrosion-resistant permanent magnet for an intravascular blood pump |
| US11967454B2 (en) | 2016-11-02 | 2024-04-23 | Abiomed Europe Gmbh | Intravascular blood pump comprising corrosion resistant permanent magnet |
-
2001
- 2001-11-20 JP JP2001354169A patent/JP2002212750A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006049863A (en) * | 2004-06-30 | 2006-02-16 | Shin Etsu Chem Co Ltd | Corrosion resistant rare earth magnet and manufacturing method thereof |
| JP2006165218A (en) * | 2004-12-07 | 2006-06-22 | Shin Etsu Chem Co Ltd | Rtmb-based rare earth permanent magnet and manufacturing method therefor |
| JP4506965B2 (en) * | 2004-12-07 | 2010-07-21 | 信越化学工業株式会社 | R-T-M-B rare earth permanent magnet and method for producing the same |
| US11967454B2 (en) | 2016-11-02 | 2024-04-23 | Abiomed Europe Gmbh | Intravascular blood pump comprising corrosion resistant permanent magnet |
| EP3822996A1 (en) * | 2019-11-12 | 2021-05-19 | Abiomed Europe GmbH | Corrosion-resistant permanent magnet for an intravascular blood pump |
| WO2021094297A1 (en) * | 2019-11-12 | 2021-05-20 | Abiomed Europe Gmbh | Corrosion-resistant permanent magnet for an intravascular blood pump |
| EP4095872A1 (en) * | 2019-11-12 | 2022-11-30 | Abiomed Europe GmbH | Corrosion-resistant permanent magnet for an intravascular blood pump |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4591631B2 (en) | Corrosion-resistant magnet and manufacturing method thereof | |
| EP1180771B1 (en) | Rare earth metal-based permanent magnet having corrosion-resistant film and method for producing the same | |
| JP2000199074A (en) | Deposition type surface treating liquid of rare earth- iron sintered permanent magnet, its surface treatment, and rare earth-iron sintered permanent magnet having surface treated by that surface treatment | |
| JPH11307328A (en) | Corrosion resistant permanent magnet and its manufacture | |
| JP4678118B2 (en) | Coated R-T-B magnet and method for manufacturing the same | |
| WO2011081170A1 (en) | Corrosion-resistant magnet and method for producing the same | |
| WO2007091602A1 (en) | Process for production of rare earth permanent magnets having copper plating films on the surfaces | |
| JPH03173106A (en) | Rare earth permanent magnet with corrosion resistant film and manufacture thereof | |
| JP2002212750A (en) | Film deposition method for r-t-b based magnet | |
| US9275795B2 (en) | Corrosion-resistant magnet and method for producing the same | |
| JP3176597B2 (en) | Corrosion resistant permanent magnet and method for producing the same | |
| JP3698308B2 (en) | Magnet and manufacturing method thereof | |
| JP3351768B2 (en) | Method for producing Fe-BR based permanent magnet having corrosion resistant film | |
| JP2002198241A (en) | Rare earth permanent magnet having corrosion resistant film, and its manufacturing method | |
| JP2004111516A (en) | R-t-b rare earth magnet of high corrosion resistance | |
| JP2004327966A (en) | Iron phosphate based film-coated r-t-b based magnet and its formation treatment method | |
| JP3580521B2 (en) | Manufacturing method of high corrosion resistant permanent magnet | |
| JP3248982B2 (en) | Permanent magnet and manufacturing method thereof | |
| JPH04288804A (en) | Permanent magnet and manufacture thereof | |
| JP3514800B2 (en) | Soft magnetic thin film and method of manufacturing the same | |
| JP2006013399A (en) | Corrosion-resistant rare earth-based permanent magnet and manufacturing method thereof | |
| JP2018198280A (en) | Nitride-based bond magnet | |
| JP2002184615A (en) | Fe-B-R PERMANENT MAGNET HAVING CORROSION-RESISTANT FILM | |
| JP3740551B2 (en) | Method for manufacturing permanent magnet | |
| JP4899928B2 (en) | Rare earth magnet manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A712 Effective date: 20040526 |