JP4313141B2 - Method for producing laminated body of magnetic substrate, and laminated body of magnetic substrate obtained thereby - Google Patents

Method for producing laminated body of magnetic substrate, and laminated body of magnetic substrate obtained thereby Download PDF

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JP4313141B2
JP4313141B2 JP2003342669A JP2003342669A JP4313141B2 JP 4313141 B2 JP4313141 B2 JP 4313141B2 JP 2003342669 A JP2003342669 A JP 2003342669A JP 2003342669 A JP2003342669 A JP 2003342669A JP 4313141 B2 JP4313141 B2 JP 4313141B2
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magnetic
resin
laminated body
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laminate
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JP2005110442A (en
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光伸 吉田
展弘 丸子
洋 渡辺
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NAKAGAWA SPECIAL STEEL CO., INC.
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Description

本発明はモータコアおよび製造方法に関する。特に、モータコアに用いられる磁性基材の積層体に関するものである。   The present invention relates to a motor core and a manufacturing method. In particular, the present invention relates to a laminate of magnetic base materials used for motor cores.

従来、磁性金属薄板を積層体にする場合、磁性金属薄板に樹脂などを塗布した後に、複数枚を積層し、さらに打ち抜きカシメ工程によりモータコアを作製する方法が取られていた(特許文献1)。しかしながら、カシメ工程のみでは、現在公知の磁性金属薄板のうち、10μmから200μm程度の極めて薄い磁性金属薄板を、実用的な機械的強度で積層一体化することが難しい。一般にこうした薄板のカシメにより一体化された積層体は、電気的絶縁と機械強度の向上のために、さらに樹脂を含浸、硬化するなどして、積層体としての機械的強度を確保すること等が行われる。また同様な方法により非晶質金属薄帯などの薄板と、比較的加工性の良い電磁鋼板を樹脂フィルムを介して一体化した後に、打ち抜きカシメ工程によりモータコアが作製されている。(特許文献2)。
特開平9−215279 特開2003−259610
Conventionally, when a magnetic metal thin plate is used as a laminated body, after applying a resin or the like to the magnetic metal thin plate, a plurality of sheets are laminated, and a motor core is manufactured by a stamping caulking process (Patent Document 1). However, with only the caulking process, it is difficult to stack and integrate extremely thin magnetic metal sheets of about 10 μm to 200 μm with practical mechanical strength among currently known magnetic metal sheets. In general, a laminated body integrated by caulking of such a thin plate can ensure mechanical strength as a laminated body by further impregnating and curing a resin in order to improve electrical insulation and mechanical strength. Done. In addition, after a thin plate such as an amorphous metal ribbon and an electromagnetic steel plate having relatively good workability are integrated through a resin film by a similar method, a motor core is manufactured by a stamping caulking process. (Patent Document 2).
JP 9-215279 A JP 2003-259610 A

しかしながら従来技術では、カシメにより積層一体化したものは、金属薄板間に空隙ができ機械的強度および占積率が低下する。また樹脂を含浸する場合、積層体の金属層間に十分に樹脂が回りこみにくく、接着層に厚みムラや空隙等が発生しやすく、積層体の機械的強度にばらつきがあったりした。   However, in the prior art, the one that is laminated and integrated by caulking causes a gap between the metal thin plates, and the mechanical strength and the space factor decrease. Further, when the resin is impregnated, the resin is not easily spread between the metal layers of the laminated body, thickness unevenness or voids are easily generated in the adhesive layer, and the mechanical strength of the laminated body varies.

また、樹脂フィルムを張り合わせる場合、電子部品や電気機器などに適用する場合の実用的な強度や耐熱性を有する樹脂フィルムは、薄くても数十μmであり、特に厚さが数十μmから0.3mm程度の磁性金属薄板をこのような樹脂フィルムで貼り合わせると占積率が大きく低下する。   In addition, when the resin film is laminated, the resin film having practical strength and heat resistance when applied to an electronic component or an electric device is several tens μm even if it is thin. When a magnetic metal thin plate of about 0.3 mm is bonded with such a resin film, the space factor is greatly reduced.

またこのような積層体を高速回転型モータのロータやステータなどに用いる場合は、機械的強度の弱い部分が遠心力により破壊し、さらなる高速回転化の障害となる。   Further, when such a laminate is used for a rotor or a stator of a high-speed rotation type motor, a portion having a low mechanical strength is broken by a centrifugal force, which becomes an obstacle to further high-speed rotation.

本発明は、占積率に優れ、高速回転型モータのロータやステータなどに用いるのに十分な機械的強度のある積層体を提供することを目的とする。   An object of the present invention is to provide a laminate having an excellent space factor and sufficient mechanical strength to be used for a rotor, a stator or the like of a high-speed rotary motor.

そこで、本発明では上記の課題に対して、以下の方法により解決できることを見出した。すなわち、磁性金属薄板の表面に、溶剤に高分子化合物を溶かしたワニスを薄く均一に、磁性金属薄板の全面に塗布、乾燥させた後、所望の形状にプレス機などで打ち抜き、カシメにより積層一体化し、さらに樹脂が溶融あるいは硬化する温度で加熱し、塗布した樹脂により、磁性金属薄板同士を接着し、積層一体化する。   Therefore, the present invention has found that the above problem can be solved by the following method. In other words, varnish in which a polymer compound is dissolved in a solvent is thinly and evenly applied to the entire surface of the magnetic metal thin plate, dried, punched into a desired shape with a press, etc., and laminated together by caulking Then, the resin is heated at a temperature at which the resin melts or hardens, and the magnetic metal thin plates are bonded to each other by the applied resin, and are laminated and integrated.


本発明では高分子化合物層を磁性金属薄板上に形成する方法として、塗工方法を用いることにより、数ミクロン程度の極めて薄い高分子化合物層を、磁性金属薄板上に形成できるため、積層体の磁性金属薄板の占積率を極めて高くできる。その結果、磁性金属薄板からなる積層体の飽和磁束密度を向上することができる。

In the present invention, as a method of forming the polymer compound layer on the magnetic metal thin plate, an extremely thin polymer compound layer of about several microns can be formed on the magnetic metal thin plate by using a coating method. The space factor of the magnetic metal thin plate can be made extremely high. As a result, it is possible to improve the saturation magnetic flux density of the laminate made of the magnetic metal thin plate.

含浸と異なり、磁性金属薄板の全面に隙間なく樹脂が塗工されているため、積層一体化したときに、空隙が生じにくく、磁性金属薄板間の密着強度を極めて高くすることが可能となる。   Unlike impregnation, since the resin is coated on the entire surface of the magnetic metal thin plate without any gaps, voids are not easily generated when laminated and integrated, and the adhesion strength between the magnetic metal thin plates can be extremely increased.

また本方法によって製造された、磁性金属薄板積層体は、均一に樹脂が塗工され、金属薄板積層体を接着するため、積層体の機械的強度のばらつきが小さく、信頼性を高くすることが可能となる。   In addition, the magnetic metal thin plate laminate produced by this method is uniformly coated with resin and adheres the metal thin plate laminate, so that the mechanical strength variation of the laminate is small and the reliability can be increased. It becomes possible.

また高速回転時の大きな応力に耐えうる高強度なモータ用積層体を実現することが可能となる。その結果、本発明の積層体および製造方法は、モータの大幅な小型化を実現する上で極めて有効である。   In addition, it is possible to realize a high-strength motor laminate that can withstand a large stress during high-speed rotation. As a result, the laminate and the manufacturing method of the present invention are extremely effective in realizing a significant downsizing of the motor.

本発明の最良の形態について説明する。   The best mode of the present invention will be described.

(磁性金属)
本発明の積層体を構成する磁性金属薄板としては、公知の金属磁性体であれば用いることができる。具体的には、ケイ素の含有量が3%から6.5%の実用化されているケイ素鋼板、パーマロイ、ナノ結晶金属磁性材料、非晶質金属磁性材料を挙げることができる。特に発熱が低く、低損失材料である材料が好ましく、非晶質金属磁性材料、ナノ結晶金属磁性材料、が好適に用いられる。
(Magnetic metal)
As a magnetic metal thin plate which comprises the laminated body of this invention, if it is a well-known metal magnetic body, it can be used. Specific examples include silicon steel plates, permalloy, nanocrystalline metal magnetic materials, and amorphous metal magnetic materials that have been put into practical use with a silicon content of 3% to 6.5%. In particular, a material that has a low heat generation and is a low-loss material is preferable, and an amorphous metal magnetic material and a nanocrystalline metal magnetic material are preferably used.

また、本発明の積層体は、これらの金属磁性薄板のいずれか一種類もしくは、複数種類を組み合わせて、積層一体化することが可能である。   In addition, the laminate of the present invention can be laminated and integrated by combining any one of these metal magnetic thin plates or a plurality of types.

非晶質金属磁性材料としては、Fe系、Co系の非晶質金属薄帯が用いられる。これらの非晶質金属薄帯は、通常溶融金属を急冷ロールを用いて急冷することにより得られる。通常は10 〜50μmの厚さであり、好ましくは10〜30μmの厚さの薄帯が用いられる。   As the amorphous metal magnetic material, Fe-based and Co-based amorphous metal ribbons are used. These amorphous metal ribbons are usually obtained by quenching molten metal using a quenching roll. Usually, a thickness of 10 to 50 μm is used, and a ribbon having a thickness of 10 to 30 μm is preferably used.

非晶質金属材料としては、一般式(Fe1-xx100-a-b-cSiabM'c(式中、MはCoおよび/またはNiを表わし、M'はNb、Mo、Zr、W、Ta、Hf、Ti、V、Cr、Mn、Y、Pd、Ru、Ga、Ge、C、Pから選ばれる1種類以上の元素を表わす。xは原子比を、a、b、cは原子%を示し、それぞれ0≦x<1、0≦a≦24、4≦b≦30、0≦c≦10を満たすものとする。)で表わされる組成を有する非晶質金属材料を挙げることができる。特に高透磁率が要求される用途においてはCoを主成分とする非晶質金属を用いることが好ましい。またモータや、磁気シールドなど、高密度の磁束を貫通させて使用する用途においては、飽和磁束密度の高いFeを主成分とする非晶質金属を用いることが好ましい。 The amorphous metallic material, the general formula (Fe 1-x M x) 100-abc Si a B b M 'c ( wherein, M represents Co and / or Ni, M' is Nb, Mo, Zr , W, Ta, Hf, Ti, V, Cr, Mn, Y, Pd, Ru, Ga, Ge, C, P represents one or more elements, where x is an atomic ratio, a, b, c Represents atomic% and satisfy the following conditions: 0 ≦ x <1, 0 ≦ a ≦ 24, 4 ≦ b ≦ 30, and 0 ≦ c ≦ 10). be able to. In particular, in applications where high magnetic permeability is required, it is preferable to use an amorphous metal containing Co as a main component. In applications where high-density magnetic flux is penetrated, such as motors and magnetic shields, it is preferable to use an amorphous metal mainly composed of Fe having a high saturation magnetic flux density.

Fe系非晶質金属材料としては、Fe−B―Si系、Fe−B系、Fe−P−C系などのFe−半金属系非晶質金属材料や、Fe−Zr系、Fe−Hf系、Fe−Ti系などのFe−遷移金属系非晶質金属材料を挙げることができる。例えば、Fe−Si−B系においては、Fe78Si913(at%)、Fe78Si1012(at%)、Fe81Si13.513.5(at%)、Fe81Si13.513.52(at%)、Fe77Si516Cr2(at%)、Fe66Co18Si115(at%)、Fe74Ni4Si217Mo3(at%)などを挙げることができる。中でもFe78Si913(at%)、Fe77Si516Cr2(at%)が好ましく用いられ、特にFe78Si913(at%)が好ましく用いられる。 Fe-based amorphous metal materials include Fe-B-Si-based, Fe-B-based, and Fe-PC-based Fe-semi-metallic amorphous metal materials, Fe-Zr-based, Fe-Hf, and the like. Fe-transition metal amorphous metal materials such as Fe-Ti and Fe-Ti. For example, in the Fe—Si—B system, Fe 78 Si 9 B 13 (at%), Fe 78 Si 10 B 12 (at%), Fe 81 Si 13.5 B 13.5 (at%), Fe 81 Si 13.5 B 13.5 C 2 (at%), Fe 77 Si 5 B 16 Cr 2 (at%), Fe 66 Co 18 Si 1 B 15 (at%), Fe 74 Ni 4 Si 2 B 17 Mo 3 (at%), etc. be able to. Of these, Fe 78 Si 9 B 13 (at%) and Fe 77 Si 5 B 16 Cr 2 (at%) are preferably used, and Fe 78 Si 9 B 13 (at%) is particularly preferably used.

Co系非晶質金属材料の組成系としては、Co−Si−B系、Co−B系などが例示できる。これらの中でも、非晶質金属薄帯の組成が、一般式(Co1-cFec100-a-b(式中、XはSi,B,C,Geから選ばれる少なくとも1種類以上の元素を表わし、YはZr,Nb,Ti,Hf,Ta,W,Cr,Mo,V,Ni,P,Al,Pt,Ph,Ru,Sn,Sb,Cu,Mn,希土類元素から選ばれる少なくとも1種類以上の元素で表される。a,b,cは原子%を示し、それぞれ、10<a≦35、0≦b≦30、0≦c≦0.2を満たすものとする。)で表される組成が好ましい。 Examples of the composition system of the Co-based amorphous metal material include a Co-Si-B system and a Co-B system. Among these, at least the composition of the amorphous metal ribbon, the general formula (Co 1-c Fe c) in 100-a-b X a Y b ( wherein, X is selected Si, B, C, Ge, Y represents Zr, Nb, Ti, Hf, Ta, W, Cr, Mo, V, Ni, P, Al, Pt, Ph, Ru, Sn, Sb, Cu, Mn, rare earth element A, b, and c represent atomic%, and satisfy 10 <a ≦ 35, 0 ≦ b ≦ 30, and 0 ≦ c ≦ 0.2, respectively. Is preferred.

上記非晶質金属薄帯のCoのFe置換は非晶質合金の飽和磁化の増加に寄与する傾向にある。このため、置換量cは0≦c≦0.2であることが好ましい。さらに、0≦c≦0.1であることが好ましい。   Co substitution of Fe in the amorphous metal ribbon tends to contribute to an increase in saturation magnetization of the amorphous alloy. For this reason, the substitution amount c is preferably 0 ≦ c ≦ 0.2. Furthermore, it is preferable that 0 ≦ c ≦ 0.1.

X元素は本発明に用いる非晶質金属薄帯を製造する上で、非晶質化のために結晶化速度を低減するために有効な元素である。X元素が10原子%より少ないと、非晶質化が低下して一部結晶質が混在し、また、35原子%を超えると、非晶質構造は得られるものの合金薄帯の機械的強度が低下し、連続的な薄帯が得られなくなる。したがって、X元素の量aは、10<a≦35であることが好ましく、さらに好ましくは、12≦a≦30である。   The element X is an effective element for reducing the crystallization speed for making amorphous when producing the amorphous metal ribbon used in the present invention. If the amount of element X is less than 10 atomic%, amorphization is reduced and some crystalline is mixed. If it exceeds 35 atomic%, an amorphous structure is obtained, but the mechanical strength of the alloy ribbon is obtained. Decreases and a continuous ribbon cannot be obtained. Therefore, the amount a of the X element is preferably 10 <a ≦ 35, and more preferably 12 ≦ a ≦ 30.

Y元素は、本発明に用いる非晶質金属薄帯の耐食性に効果がある。この中で特に有効な元素は、Zr,Nb,Mn,W,Mo,Cr,V,Ni,P,Al,Pt,Ph,Ru元素である。Y元素の添加量は30%以上になると、耐食性の効果はあるが、薄帯の機械的強度が脆弱になるため、0≦b≦30であることが好ましい。さらに好ましい範囲は、0≦b≦20である。   Y element is effective in the corrosion resistance of the amorphous metal ribbon used in the present invention. Among these, particularly effective elements are Zr, Nb, Mn, W, Mo, Cr, V, Ni, P, Al, Pt, Ph, and Ru. If the amount of Y element added is 30% or more, there is an effect of corrosion resistance, but the mechanical strength of the ribbon becomes weak, so 0 ≦ b ≦ 30 is preferable. A more preferable range is 0 ≦ b ≦ 20.

ナノ結晶性磁性金属材料としては、次のような組成の材料を挙げることができる。   Examples of the nanocrystalline magnetic metal material include materials having the following composition.

(1)一般式(Fe1-xx100-a-b-c-dSiaAlbcM'd
(式中、MはCoおよび/またはNiを表わし、M'はNb、Mo、Zr、W、Ta、Hf、Ti、V、Cr、Mn、Pd、Ru、Ge、C、P、希土類元素から選ばれる1種類以上の元素を表わす。xは原子比を、a、b、c、dは原子%を示し、それぞれ0≦x≦0.5、0≦a≦24、0.1<b≦20、4≦c≦30、0≦d≦20を満たすものとする。)で表わされる組成。
(1) General formula (Fe 1-x M x ) 100-abcd Si a Al b B c M ′ d
(In the formula, M represents Co and / or Ni, M ′ represents Nb, Mo, Zr, W, Ta, Hf, Ti, V, Cr, Mn, Pd, Ru, Ge, C, P, rare earth elements. Represents one or more selected elements, where x is an atomic ratio, a, b, c, and d are atomic%, and 0 ≦ x ≦ 0.5, 0 ≦ a ≦ 24, and 0.1 <b ≦, respectively. 20, 4 ≦ c ≦ 30, 0 ≦ d ≦ 20).

(2)一般式(Fe1-xx100-a-b-c-dCuaSibcM'd
(式中、MはCoおよび/またはNiを表わし、M'はNb、Mo、Zr、W、Ta、Hf、Ti、V、Cr、Mn、Pd,Ru,Ge,C,P、希土類元素から選ばれる1種類以上の元素を表わす。xは原子比を、a、b、c、dは原子%を示し、それぞれ0≦x≦0.4、0.1≦a≦3、b≦19、5≦c≦25、0<d≦20、15≦b+C≦30を満たすものとする。)で表わされる組成。
(2) General formula (Fe 1-x M x ) 100-abcd Cu a Si b B c M ′ d
(Wherein M represents Co and / or Ni, and M ′ represents Nb, Mo, Zr, W, Ta, Hf, Ti, V, Cr, Mn, Pd, Ru, Ge, C, P, rare earth elements) X represents an atomic ratio, a, b, c, and d represent atomic%, and 0 ≦ x ≦ 0.4, 0.1 ≦ a ≦ 3, b ≦ 19, respectively. 5 ≦ c ≦ 25, 0 <d ≦ 20, 15 ≦ b + C ≦ 30)).

(3)一般式(Fe1-xx100-a-baM'b
(式中、MはCoおよび/またはNiを表わし、M’はNb、Mo、Zr、W、Ta、Hf、Ti、V、Cr、Mn、Pd、Ru、Ga、Ge、C、希土類元素から選ばれる1種類以上の元素を表わす。xは原子比を、a、bは原子%を示し、それぞれ0≦x≦0.5、0<a≦20、2≦b≦20を満たすものとする。)で表わされる組成。
(3) General formula (Fe 1-x M x ) 100-ab B a M ′ b
(Wherein M represents Co and / or Ni, and M ′ represents Nb, Mo, Zr, W, Ta, Hf, Ti, V, Cr, Mn, Pd, Ru, Ga, Ge, C, and rare earth elements. Represents one or more selected elements, where x is an atomic ratio, a and b are atomic%, and satisfy 0 ≦ x ≦ 0.5, 0 <a ≦ 20, and 2 ≦ b ≦ 20, respectively. )).

(4)一般式(Fe1-xx100-a-b-caM'bCuc
(式中、MはCoおよび/またはNiを表わし、M’はNb、Mo、Zr、W、Ta、Hf、Ti、V、Cr、Mn、Pd、Ru、Ga、Ge、Al,C、希土類元素から選ばれる1種類以上の元素を表わす。xは原子比を、a、b、c、dは原子%を示し、それぞれ0≦x≦0.50<a≦20、2≦b≦20、0≦c≦3を満たすものとする。)で表わされる組成。
(4) General formula (Fe 1-x M x ) 100-abc P a M ′ b Cu c
(Wherein M represents Co and / or Ni, M ′ represents Nb, Mo, Zr, W, Ta, Hf, Ti, V, Cr, Mn, Pd, Ru, Ga, Ge, Al, C, rare earth Represents one or more elements selected from the elements, where x represents an atomic ratio, a, b, c, and d represent atomic%, and 0 ≦ x ≦ 0.50 <a ≦ 20, 2 ≦ b ≦ 20, 0 ≦ c ≦ 3)).

(5)一般式(Fe1-x100-a-baM'b
(式中、MはCoおよび/またはNiを表わし、M'はTa、Zr,Hf、Ti,Nb、Mo、W、V、Cr、Mn、Pd、Ru、Ga、Ge、Si、Al、P、Cu、希土類元素から選ばれる1種類以上の元素を表わし、M’はC、N、Oから選ばれる1種類以上の元素を表わす。xは原子比を、a、bは原子%を示し、それぞれ0≦x≦0.52<a≦304≦b≦30を満たすものとする。)で表わされる組成。
(5) General formula (Fe 1-x M x ) 100-ab M a M ′ b
(Wherein M represents Co and / or Ni, and M ′ represents Ta, Zr, Hf, Ti, Nb, Mo, W, V, Cr, Mn, Pd, Ru, Ga, Ge, Si, Al, P , Cu, and one or more elements selected from rare earth elements, M ′ represents one or more elements selected from C, N, and O. x represents an atomic ratio, a and b represent atomic%, Each satisfying 0 ≦ x ≦ 0.52 <a ≦ 304 ≦ b ≦ 30).

これらの磁性材料は、公知の方法、たとえば加熱処理によりナノ結晶材料とすることができる。   These magnetic materials can be made into a nanocrystalline material by a known method, for example, heat treatment.

(樹脂)
本発明で用いられる高分子化合物としては、公知のいわゆる樹脂と呼ばれるものを用いることができるが、金属磁性材料の磁気特性向上のために200℃以上の熱処理が必要な場合には、弾性率の低い耐熱樹脂を複合することが、優れた性能を発揮する上で効果的である。本発明に用いられる磁性金属薄帯の良好な磁気特性を発言させるための熱処理温度は、通常、200〜700℃の範囲にあり、さらに好ましくは300℃〜600℃の範囲である。
(resin)
As the polymer compound used in the present invention, a known so-called resin can be used. However, when heat treatment at 200 ° C. or higher is required for improving the magnetic properties of the metal magnetic material, the elastic modulus is Combining a low heat resistant resin is effective in achieving excellent performance. The heat treatment temperature for expressing good magnetic properties of the magnetic metal ribbon used in the present invention is usually in the range of 200 to 700 ° C, more preferably in the range of 300 to 600 ° C.

本発明において耐熱性樹脂とは、窒素雰囲気下300℃、2時間の熱履歴を経た際の熱分解による重量減少率が5重量%以下のものであり、さらに、以下の特性を1つ以上有していることが好ましい。
(1)窒素雰囲気下350℃、2時間の熱履歴を経た後の引っ張り強度が30MPa以上であること、
(2)ガラス転移温度が120℃〜250℃であること、
(3)融粘度が1000Pa・sである温度が、250℃以上400℃以下であること、
(4)400℃から120℃まで0.5℃/分の一定速度で降温した後、樹脂中の結晶物による融解熱が10J/g以下であること。
In the present invention, the heat-resistant resin is one having a weight reduction rate of 5% by weight or less due to thermal decomposition at 300 ° C. for 2 hours in a nitrogen atmosphere, and further has one or more of the following characteristics. It is preferable.
(1) The tensile strength after passing through a thermal history at 350 ° C. for 2 hours in a nitrogen atmosphere is 30 MPa or more,
(2) The glass transition temperature is 120 ° C to 250 ° C,
(3) The temperature at which the melt viscosity is 1000 Pa · s is 250 ° C. or higher and 400 ° C. or lower,
(4) After the temperature is lowered from 400 ° C. to 120 ° C. at a constant rate of 0.5 ° C./min, the heat of fusion due to the crystalline material in the resin is 10 J / g or less.

本発明で用いることができる耐熱性樹脂としては、前処理として120℃で4時間乾燥を施し、その後、窒素雰囲気下、300℃で2時間保持した際のDTA−TGを用いて測定した重量減少量が、通常1%以下、好ましくは0.3%以下であるものが用いられる。具体的な樹脂としては、ポリイミド系樹脂、ケイ素含有樹脂、ケトン系樹脂、ポリアミド系樹脂、液晶ポリマー,ニトリル系樹脂,チオエ−テル系樹脂,ポリエステル系樹脂,アリレ−ト系樹脂,サルホン系樹脂,イミド系樹脂,アミドイミド系樹脂を挙げることができる。これらのうちポリイミド系樹脂,スルホン系樹脂、アミドイミド系樹脂を用いるのが好ましい。   The heat-resistant resin that can be used in the present invention is a weight loss measured using DTA-TG when dried at 120 ° C. for 4 hours as a pretreatment and then kept at 300 ° C. for 2 hours in a nitrogen atmosphere. The amount is usually 1% or less, preferably 0.3% or less. Specific resins include polyimide resins, silicon-containing resins, ketone resins, polyamide resins, liquid crystal polymers, nitrile resins, thioether resins, polyester resins, arylate resins, sulfone resins, Examples thereof include imide resins and amide imide resins. Of these, it is preferable to use polyimide resins, sulfone resins, and amideimide resins.

また本発明において200℃以上の耐熱性を必要としない場合、これに限定されないが、本発明で用いることができる具体的な熱可塑性樹脂としては、ポリエーテルサルホン、ポリエーテルイミド、ポリエーテルケトン、ポリエチレンテレフタレート、ナイロン、ポリブチレンテレフタレート、ポリカーボネート、ポリフェニレンエーテル、ポリフェニレンスルフィド、ポリサルホン、ポリアミド、ポリアミドイミド、ポリ乳酸、ポリエチレン、ポリプロピレン、エポキシ樹脂、シリコン樹脂、ゴム系樹脂(クロロプレンゴム、シリコンゴム)などを挙げることができる。   Further, in the present invention, when heat resistance of 200 ° C. or higher is not required, the present invention is not limited to this. Specific thermoplastic resins that can be used in the present invention include polyethersulfone, polyetherimide, polyetherketone. , Polyethylene terephthalate, nylon, polybutylene terephthalate, polycarbonate, polyphenylene ether, polyphenylene sulfide, polysulfone, polyamide, polyamideimide, polylactic acid, polyethylene, polypropylene, epoxy resin, silicone resin, rubber resin (chloroprene rubber, silicone rubber), etc. Can be mentioned.

また本発明の樹脂層の厚みは0.1μm〜1mmの範囲が好ましく、さらに好ましくは0.5μm〜10μmが良く、さらに好ましくは1μm〜6μmが良い。   The thickness of the resin layer of the present invention is preferably in the range of 0.1 μm to 1 mm, more preferably 0.5 μm to 10 μm, and further preferably 1 μm to 6 μm.

(塗工方法)
本発明において磁性基材とは、磁性金属薄板の片面に樹脂を塗工したものをいう。磁性金属薄帯に樹脂を塗工する方法としては、有機溶剤に樹脂を溶解させた樹脂ワニスをロールコーターなどを用いて塗工することが一般的である。
(Coating method)
In the present invention, the magnetic substrate refers to a resin coated on one side of a magnetic metal thin plate. As a method of applying a resin to a magnetic metal ribbon, it is common to apply a resin varnish obtained by dissolving a resin in an organic solvent using a roll coater or the like.

樹脂の粘度は、通常0.005〜200Pa・sの濃度範囲であり、好ましくは0.01〜50Pa・sであり,より好ましくは0.05〜5Pa・sの範囲である。粘度が、0.005Pa・s未満になると、粘性が低くなり過ぎるため非晶質金属薄帯上から流れてしまい薄板上に十分な塗膜量が得られず、極めて薄い塗膜になることがある。粘度が、200Pa・sを超えると、高粘度のため、非晶質金属薄帯上に薄い塗膜を形成するための膜厚の制御が極めて難しくなる。   The viscosity of the resin is usually in a concentration range of 0.005 to 200 Pa · s, preferably 0.01 to 50 Pa · s, and more preferably 0.05 to 5 Pa · s. When the viscosity is less than 0.005 Pa · s, the viscosity becomes too low, so that it flows from the amorphous metal ribbon, and a sufficient coating amount cannot be obtained on the thin plate, resulting in an extremely thin coating film. is there. When the viscosity exceeds 200 Pa · s, it is extremely difficult to control the film thickness for forming a thin coating film on the amorphous metal ribbon due to the high viscosity.

上記のような液状樹脂を塗布する方法としては、コーターを用いた方法、例えば、ロールコーター法、(マイクロ)グラビアコーター法、エアドクタコーター法、ブレ−ドコーター法、ナイフコーター法、ロッドコーター法、キスコーター法、ビードコーター法、キャストコーター法、ロータリースクリーン法、あるいはインクジェット法、液状樹脂中に非晶質金属薄帯を浸漬しながらコーティングする浸漬コーティング方法、液状樹脂を磁性金属薄帯にオリフィスから落下させコーティングするスロットオリフィスコーター法、バーコード法、霧吹きの原理を用いて液状樹脂を霧上に磁性金属薄帯に吹き付けるスプレーコーティング法、スピンコーティング法、電着コーティング法、スパッタ法のような物理的な蒸着法、CVD法のような気相法などが挙げられる。また塗工する樹脂層の厚みは0.1μm〜1mmであることが好ましく、より好ましくは1μm〜100μmであり、さらに好ましくは1μm〜10μmである。樹脂層が薄いほど積層体としての占積率が高くなり、積層体の飽和磁束密度の向上を図ることが可能となる。   As a method of applying the liquid resin as described above, a method using a coater, for example, a roll coater method, a (micro) gravure coater method, an air doctor coater method, a blade coater method, a knife coater method, a rod coater method, Kiss coater method, bead coater method, cast coater method, rotary screen method, or ink jet method, dip coating method of coating while immersing amorphous metal ribbon in liquid resin, dropping liquid resin to magnetic metal ribbon from orifice Physical coating such as slot orifice coater method, bar code method, spray coating method, spray coating method, spray coating method, electrodeposition coating method, sputtering method in which liquid resin is sprayed onto magnetic metal ribbon on mist using the principle of spraying Like vapor deposition, CVD Such as the phase, and the like. Moreover, it is preferable that the thickness of the resin layer to apply is 0.1 micrometer-1 mm, More preferably, they are 1 micrometer-100 micrometers, More preferably, they are 1 micrometer-10 micrometers. The thinner the resin layer, the higher the space factor of the laminate, and the saturation magnetic flux density of the laminate can be improved.

(打ち抜きかしめ工程)
本発明の樹脂を塗工した磁性金属薄板は、打ち抜きかしめ工程によって積層体となる。この工程は、まず公知の磁性金属薄板の形状加工技術であるプレス打ち抜き加工により所望の形状にカットし、次に、材料の一部をつぶして二つ以上の金属薄板を接合する公知のかしめ加工により、複数枚の磁性金属薄板を接合し、積層体とする。しかしながら、打ち抜く磁性金属薄板材料が数十μm〜数100μmと薄い場合はかしめのみでは十分な接合強度を達成することが難しいため、以下の加熱一体化工程により樹脂接着する。
(Punching and crimping process)
The magnetic metal thin plate coated with the resin of the present invention becomes a laminate by a stamping and caulking process. This process is a known caulking process in which a known shape of a magnetic metal sheet is first cut into a desired shape by press punching, and then a part of the material is crushed to join two or more metal sheets. Thus, a plurality of magnetic metal thin plates are joined to form a laminated body. However, when the punched magnetic metal thin plate material is as thin as several tens of μm to several hundreds of μm, it is difficult to achieve sufficient bonding strength only by caulking. Therefore, resin bonding is performed by the following heat integration process.

(加熱一体化工程)
本発明の積層一体化方法は、塗工された高分子化合物が、熱硬化性樹脂の場合は 塗工された高分子化合物が、金属薄板同士を接着硬化する温度に加熱した後、放冷した後、常温に戻す。また塗工された高分子化合物が熱可塑性樹脂の場合は熱可塑性樹脂のガラス転移点温度以上の温度で、樹脂が溶融流動性を有した状態にまで加熱した後、放冷し、常温に戻す。このとき、カシメにより積層体として、磁性金属薄板が固定されているため、治具等で、積層体を固定していなくとも、樹脂が溶融流動性を帯びたときに積層体のずれ等がなく、高い寸法安定性の確保が容易となる。また、塗工された高分子化合物が本発明の耐熱樹脂であり、磁性金属薄板が本発明の非晶質金属薄帯や、ナノ結晶金属磁性薄帯などである場合、積層一体化後に、焼鈍処理を行うことにより、積層体の磁気特性の向上を図ることも可能である。
(実施例1)
本発明の実施例について説明する。まず磁性金属薄板として、非晶質金属薄帯(ハネウェル社製、Metglas(登録商標) :2605TCA、幅約213mm 、厚み約25μmFe78Si13(at %)の組成を持つ非晶質金属薄帯)を使用した。この薄帯の両面全面に約0 .3Pa ・s の粘度のポリアミド酸溶液を付与し、150 ℃で溶媒を揮発させた後、250 ℃でポリイミド樹脂とし、磁性金属薄板の片面に厚さ約3ミクロンの耐熱性樹脂(ポリイミド樹脂)を付与した非晶質金属薄帯を作製した。耐熱性樹脂として、ジアミンに3 、3’−ジアミノジフェニルエーテル、テトラカルボン酸二無水物にビス(3 、4−ジカルボキシフェニル)エーテルニ無水物により得られるポリイミドの前駆体であるポリアミド酸を用い、ジメチルアセトアミドの溶媒に溶解して非晶質金属薄帯上に塗布し、非晶質金属薄帯上で250℃で加熱してことにより、ポリイミド樹脂とした。
(Heating integration process)
In the laminated integration method of the present invention, when the coated polymer compound is a thermosetting resin, the coated polymer compound is heated to a temperature at which the metal thin plates are bonded and cured, and then allowed to cool. Then return to room temperature. When the applied polymer compound is a thermoplastic resin, the resin is heated to a temperature above the glass transition temperature of the thermoplastic resin until the resin has melt flowability, and then allowed to cool to return to room temperature. . At this time, since the magnetic metal thin plate is fixed as a laminated body by caulking, even if the laminated body is not fixed with a jig or the like, there is no deviation of the laminated body when the resin has melt fluidity. It is easy to ensure high dimensional stability. In addition, when the coated polymer compound is the heat-resistant resin of the present invention and the magnetic metal thin plate is the amorphous metal thin film of the present invention or the nanocrystalline metal magnetic thin film, annealing is performed after stacking and integration. By performing the treatment, it is possible to improve the magnetic properties of the laminate.
Example 1
Examples of the present invention will be described. First, an amorphous metal ribbon (Metglas (registered trademark): 2605TCA, width: about 213 mm, thickness: about 25 μm Fe 78 Si 9 B 13 (at%), manufactured by Honeywell Co., Ltd.) is used as a magnetic metal thin plate. Band) was used. About 0. After applying a polyamic acid solution having a viscosity of 3 Pa · s and volatilizing the solvent at 150 ° C., a polyimide resin is formed at 250 ° C., and a heat resistant resin (polyimide resin) having a thickness of about 3 microns is applied to one side of the magnetic metal thin plate. An applied amorphous metal ribbon was produced. Polyamide acid, which is a polyimide precursor obtained from 3,3′-diaminodiphenyl ether as diamine and bis (3,4-dicarboxyphenyl) ether dianhydride as tetracarboxylic dianhydride, is used as the heat-resistant resin. It melt | dissolved in the solvent of acetamide, apply | coated on the amorphous metal ribbon, and it heated at 250 degreeC on the amorphous metal ribbon, and was set as the polyimide resin.

この薄帯を、長さ150mm、幅12.5mの短冊形状を10枚を打ち抜きカシメにより150mm×12.5mm×0.3mmの積層体を作製した。さらに270 ℃に加熱し非晶質金属薄帯のポリイミト゛樹脂層を溶融させ、金属薄帯同士を接着させて積層体を作製した。この積層体の占積率は90%であった。さらに積層体を350℃で2時間の熱処理を行った。   From this ribbon, 10 strips having a length of 150 mm and a width of 12.5 m were punched out to produce a laminate of 150 mm × 12.5 mm × 0.3 mm by caulking. Furthermore, it heated at 270 degreeC, the polyimide resin layer of the amorphous metal ribbon was fuse | melted, metal ribbons were adhere | attached, and the laminated body was produced. The space factor of this laminated body was 90%. Furthermore, the laminated body was heat-treated at 350 ° C. for 2 hours.

なお、占積率は次式で定義する式により計算した。   The space factor was calculated by the formula defined by the following formula.

(占積率(%))=(((非晶質金属薄帯厚さ)×(積層枚数))/(積層後の積層体厚さ))×100
さ らに、さらにJIS Z2241 に従い、さきの積層体と同様のプロセスで作製した磁性積層板の引張強度を測定したところ、800MPa となり、熱処理後でも非常に強い機械強度を有していることが明らかとなった。
(Space factor (%)) = (((Amorphous metal ribbon thickness) × (Number of laminated layers)) / (Laminated body thickness after lamination)) × 100
Furthermore, according to JIS Z2241, when the tensile strength of the magnetic laminate produced by the same process as the previous laminate was measured, it was 800 MPa, and it was clear that it had a very strong mechanical strength even after heat treatment. It became.

(比較例1)まず磁性金属薄板として、非晶質金属薄帯(ハネウェル社製、Metglas(登録商標) :2605TCA、幅約213mm、厚み約25μmのFe78Si13(at %)の組成を持つ非晶質金属薄帯)を使用した。この薄帯で、厚さ20μmの東レデュポン(株)製カプトンフィルム(登録商標):100F099、厚さ25μmをサンドイッチし、押圧して、積層体とした。さらに、この薄帯を、長さ150mm、幅12.5mの短冊形状に打ち抜き、打ち抜いた板を4枚、カシメて150mm×12.5mm×0.3mmの積層体とした。さらに270 ℃に加熱し非晶質金属薄帯のポリイミト゛樹脂層を溶融させ、金属薄帯同士を接着させて積層体を作製した。この積層体の占積率は50%であった。さらに積層体を350℃2 時間の焼鈍熱処理を行った。 (Comparative Example 1) First, a composition of an amorphous metal ribbon (Metglas (registered trademark): 2605TCA, width about 213 mm, thickness about 25 μm, Fe 78 Si 9 B 13 (at%)) manufactured by Honeywell as a magnetic metal thin plate. Amorphous metal ribbon with With this ribbon, a 20 μm thick Kapton film (registered trademark) manufactured by Toray DuPont Co., Ltd .: 100F099, a thickness of 25 μm was sandwiched and pressed to form a laminate. Further, the ribbon was punched into a strip shape having a length of 150 mm and a width of 12.5 m, and four punched plates were caulked to form a laminate of 150 mm × 12.5 mm × 0.3 mm. Furthermore, it heated at 270 degreeC, the polyimide resin layer of the amorphous metal ribbon was fuse | melted, metal ribbons were adhere | attached, and the laminated body was produced. The space factor of this laminate was 50%. Further, the laminate was subjected to annealing heat treatment at 350 ° C. for 2 hours.

なお、占積率は次式で定義する式により計算した。   The space factor was calculated by the formula defined by the following formula.

(占積率(%))=(((非晶質金属薄帯厚さ)×(積層枚数))/(積層後の積層体厚さ))×100
さ らに、さらにJIS Z2241 に従い、さきの積層体と同様のプロセスで作製した磁性積層板の引張強度を測定したところ、500MPa となった。
(Space factor (%)) = (((Amorphous metal ribbon thickness) × (Number of laminated layers)) / (Laminated body thickness after lamination)) × 100
Furthermore, according to JIS Z2241, the tensile strength of the magnetic laminate produced by the same process as the previous laminate was measured and found to be 500 MPa.

Figure 0004313141
Figure 0004313141

Claims (2)

非晶質磁性金属薄板上にポリイミド樹脂を塗布し乾燥させてポリイミド樹脂層を形成し、磁性基材を得る工程と、
前記磁性基材を所定の形状に打ち抜き加工する工程と、
打ち抜き加工された前記磁性基材を積み重ねて、カシメ加工する工程と、
カシメ加工した前記磁性基材を加熱して積層一体化後、さらに加熱をして積層体を形成する工程と、
を含み、
前記非晶質磁性金属薄板が10μm〜50μmの厚さであり、
前記ポリイミド樹脂層が0.5μm〜10μmの厚さであることを特徴とする、磁性基材の積層体の製造方法。
Applying a polyimide resin on an amorphous magnetic metal thin plate and drying to form a polyimide resin layer, obtaining a magnetic substrate;
Punching the magnetic base material into a predetermined shape;
Stacking the punched magnetic base material, and caulking,
Heating and crimping the magnetic base material and integrating the layers , and further heating to form a laminate; and
Including
The amorphous magnetic metal thin plate has a thickness of 10 μm to 50 μm,
The said polyimide resin layer is 0.5 micrometer-10 micrometers in thickness, The manufacturing method of the laminated body of a magnetic base material characterized by the above-mentioned.
請求項1に記載の製造方法により得られる磁性基材の積層体。   The laminated body of the magnetic base material obtained by the manufacturing method of Claim 1.
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