JP2002317235A - Ferromagnetic shape memory alloy - Google Patents
Ferromagnetic shape memory alloyInfo
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- JP2002317235A JP2002317235A JP2001118315A JP2001118315A JP2002317235A JP 2002317235 A JP2002317235 A JP 2002317235A JP 2001118315 A JP2001118315 A JP 2001118315A JP 2001118315 A JP2001118315 A JP 2001118315A JP 2002317235 A JP2002317235 A JP 2002317235A
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- shape memory
- atomic
- memory alloy
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、延性に優れ、強磁
性を有し、かつマルテンサイト変態を生じる強磁性形状
記憶合金に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ferromagnetic shape memory alloy having excellent ductility, having ferromagnetism, and causing martensitic transformation.
【０００２】[0002]
【従来の技術】機械構造物を構成する部品のうち、変
形，移動あるいは応力を発生する機能性部品はアクチュ
エーターと呼ばれる。アクチュエーターの材料として
は、圧電材料，磁歪材料，電気粘性流体，形状記憶合金
等がある。いずれの材料も、アクチュエーターの機能は
結晶構造の相変態現象を伴って発現し、物理化学的特性
値や力学的エネルギーの変換作用が関わっている。2. Description of the Related Art Among components constituting a mechanical structure, a functional component that generates deformation, movement, or stress is called an actuator. Actuator materials include piezoelectric materials, magnetostrictive materials, electrorheological fluids, shape memory alloys, and the like. In any of the materials, the function of the actuator is expressed by a phase transformation phenomenon of the crystal structure, and the action of converting physicochemical characteristics and mechanical energy is involved.
【０００３】アクチュエーター用材料のうち、形状記憶
合金は、冷却によるマルテンサイト変態と、加熱による
その逆変態機構を利用するものである。すなわち高温相
であるオーステナイト状態で形状を拘束して熱処理する
ことによって合金に形状を記憶させ、低温相であるマル
テンサイト状態で変形した後、加熱するとオーステナイ
トに戻る逆変態を生じて元の形状に戻るのである。[0003] Among actuator materials, shape memory alloys utilize a martensitic transformation by cooling and a reverse transformation mechanism by heating. In other words, the alloy is made to memorize the shape by restraining the shape in the austenite state, which is the high-temperature phase, and then heat-treated. Return.
【０００４】一般に、冷却時の変態温度よりも加熱時の
変態温度の方が高く、その温度差を温度ヒステリシスと
いう。温度ヒステリシスが小さい場合を熱弾性マルテン
サイト変態といい、約５％にも及ぶ大きな形状回復歪が
得られる。しかし熱弾性マルテンサイト変態を利用する
形状記憶合金は、温度変化によって形状記憶効果を発現
させるのであるから加熱と冷却が必要であるが、冷却過
程は熱放散で律速されるため、形状記憶効果の応答速度
が遅い。したがって形状記憶効果を繰り返し発現させる
アクチュエーターには利用し難いという問題があった。[0004] Generally, the transformation temperature during heating is higher than the transformation temperature during cooling, and the temperature difference is called temperature hysteresis. The case where the temperature hysteresis is small is called thermoelastic martensitic transformation, and a large shape recovery strain of about 5% can be obtained. However, shape memory alloys utilizing thermoelastic martensitic transformation require heating and cooling because they exhibit a shape memory effect due to temperature changes.However, the cooling process is limited by heat dissipation, so the shape memory effect is not Response speed is slow. Therefore, there is a problem that it is difficult to use the actuator for repeatedly exhibiting the shape memory effect.
【０００５】そこで近年、新しいアクチュエーター用材
料として強磁性形状記憶合金が注目されている。強磁性
形状記憶合金は、温度変化ではなく、外的に磁気エネル
ギーを付加して、磁気誘起マルテンサイト変態を生じさ
せ、形状記憶効果の応答性を高めようとするものであ
る。あるいはマルテンサイト相状態で磁場を加えると、
双晶の移動で歪みを生じる。この歪みをアクチュエータ
ーとして応用しようとするものである。[0005] In recent years, ferromagnetic shape memory alloys have attracted attention as a new actuator material. The ferromagnetic shape memory alloy is intended not to change the temperature but to add magnetic energy externally to cause a magnetically induced martensitic transformation to enhance the response of the shape memory effect. Or when a magnetic field is applied in the martensitic phase,
Distortion occurs due to twin movement. This strain is intended to be applied as an actuator.
【０００６】特開平11-269611 号公報には、鉄基磁性形
状記憶合金およびその製造方法が開示されている。この
技術は、Pd含有量が27〜32原子％のFe−Pd系合金、ある
いはPt含有量が23〜30原子％のFe−Pt系合金を基本とす
る鉄基磁性形状記憶合金に磁気エネルギーを付与して磁
気誘起マルテンサイト変態を発現させることによって、
形状記憶現象を発現させようとするものである。しかし
この技術では、材料の延性が低いので機械部品として複
雑かつ精密な形状を付与するのが困難であり、しかも原
料価格が高いため経済的にも不利であった。Japanese Patent Application Laid-Open No. 11-269611 discloses an iron-based magnetic shape memory alloy and a method for producing the same. This technology applies magnetic energy to an iron-based magnetic shape memory alloy based on an Fe-Pd-based alloy having a Pd content of 27 to 32 atomic% or an Fe-Pt-based alloy having a Pt content of 23 to 30 atomic%. By imparting and expressing magnetically induced martensitic transformation,
It is intended to develop a shape memory phenomenon. However, in this technique, it is difficult to give a complicated and precise shape as a mechanical part because the material has low ductility, and it is economically disadvantageous because the raw material price is high.
【０００７】特開平5-311287号公報には、強磁性Cu系形
状記憶材料とその製造方法が開示されている。この技術
は、Cu−Al−Mn合金粉末体を加圧して固化成形した後、
焼結および加工して、形状記憶現象を電気的スイッチン
グ装置や温度感知センサーに利用しようとするものであ
る。しかしこの技術では、粉末材料を加圧成形して焼結
した後、加工するため機械部品として複雑かつ精密な形
状を付与するのが困難であった。Japanese Patent Application Laid-Open No. Hei 5-311287 discloses a ferromagnetic Cu-based shape memory material and a method for producing the same. This technology, after pressing and solidifying the Cu-Al-Mn alloy powder body,
Sintering and processing are intended to utilize the shape memory phenomenon in electrical switching devices and temperature sensing sensors. However, according to this technique, it is difficult to impart a complicated and precise shape as a mechanical part because the powder material is pressed and sintered and then processed.
【０００８】米国特許5,958,154 号公報には、Ni−Mn−
Ga系合金のアクチュエーター用材料に磁場を付与して形
状記憶現象を発現させる技術が開示されている。しかし
この技術では、材料の延性が低いので機械部品として複
雑かつ精密な形状を付与するのが困難であり、しかも繰
り返し特性が悪いという問題があった。US Pat. No. 5,958,154 discloses that Ni-Mn-
A technique has been disclosed in which a magnetic field is applied to a Ga-based alloy actuator material to exert a shape memory phenomenon. However, in this technique, there is a problem that it is difficult to give a complicated and precise shape as a mechanical part because the ductility of the material is low, and the repetition characteristics are poor.
【０００９】[0009]
【発明が解決しようとする課題】本発明は上記のような
問題を解消し、延性に優れ、強磁性を有し、かつマルテ
ンサイト変態を生じる強磁性形状記憶合金を提供するこ
とを目的とする。SUMMARY OF THE INVENTION It is an object of the present invention to provide a ferromagnetic shape memory alloy which is excellent in ductility, has ferromagnetism and causes martensitic transformation. .
【００１０】[0010]
【課題を解決するための手段】本発明は、Coを35〜65原
子％、Gaを20〜35原子％含有し、残部がNiおよび不可避
的不純物からなる組成と、Ｂ２構造（いわゆるCeCl構
造）のβ相からなる単相組織、またはＢ２構造のβ相と
延性のあるｆｃｃ構造の第２相からなる２相組織とを有
する強磁性形状記憶合金である。According to the present invention, there is provided a composition containing 35 to 65 atomic% of Co and 20 to 35 atomic% of Ga, the balance being Ni and unavoidable impurities, and a B2 structure (a so-called CeCl structure). Or a ferromagnetic shape memory alloy having a B2 structure β phase and a ductile fcc structure second phase two phase structure.
【００１１】前記した発明においては、第１の好適態様
として、前記組成に加えて、Feを0.001〜30原子％およ
び／またはMnを 0.001〜30原子％含有することが好まし
い。また第２の好適態様として、前記組成に加えて、In
およびSiのうちの１種を 0.001〜50原子％または２種を
合計 0.001〜50原子％含有することが好ましい。In the above-mentioned invention, as a first preferred embodiment, it is preferable that 0.001 to 30 atomic% of Fe and / or 0.001 to 30 atomic% of Mn are contained in addition to the above composition. As a second preferred embodiment, in addition to the above-described composition, In
Preferably, one of Si and Si is contained in an amount of 0.001 to 50 atomic% or two kinds in total of 0.001 to 50 atomic%.
【００１２】また第３の好適態様として、前記組成に加
えて、Ｂを0.0005〜0.01原子％、Mgを0.0005〜0.01原子
％、Ｃを0.0005〜0.01原子％およびＰを0.0005〜0.01原
子％のうちの１種または２種以上含有することが好まし
い。また第４の好適態様として、前記組成に加えて、P
t，Pd，Au，Ag，Nb，Ｖ，Ti，Cr，Zr，Cu，ＷおよびMo
のうちの１種を 0.001〜10原子％または２種以上を合計
0.001〜10原子％含有することが好ましい。In a third preferred embodiment, in addition to the above composition, B is 0.0005 to 0.01 atomic%, Mg is 0.0005 to 0.01 atomic%, C is 0.0005 to 0.01 atomic%, and P is 0.0005 to 0.01 atomic%. It is preferable to contain one or more of these. As a fourth preferred embodiment, in addition to the composition, P
t, Pd, Au, Ag, Nb, V, Ti, Cr, Zr, Cu, W and Mo
0.001 to 10% by atom or one or more of them
It is preferable to contain 0.001 to 10 atomic%.
【００１３】また第５の好適態様として、前記単相組織
が単結晶であることが好ましい。また第６の好適態様と
して、前記２相組織の第２相が、Ａ１構造のγ相および
／またはＬ１2 構造のγ’相および／またはｈｃｐ構造
のε−Ｃ0 相であることが好ましい。また第７の好適態
様として、前記２相組織の第２相の体積分率が0.01〜80
体積％の範囲を満足することが好ましい。In a fifth preferred aspect, the single phase structure is preferably a single crystal. Also as a preferred embodiment of the sixth, the second phase of two-phase structure is preferably a epsilon-C 0-phase gamma 'phase and / or hcp structure of gamma phase and / or L1 2 structure A1 structure. In a seventh preferred embodiment, the volume fraction of the second phase in the two-phase structure is 0.01 to 80.
It is preferable to satisfy the range of volume%.
【００１４】[0014]
【発明の実施の形態】まず本発明の強磁性形状記憶合金
の組成について説明する。本発明の強磁性形状記憶合金
は、Coを35〜65原子％，Gaを20〜35原子％含有し、残部
がNiおよび不可避的不純物からなる。さらにFeを 0.001
〜30原子％，Mnを 0.001〜30原子％，Inを 0.001〜50原
子％，Siを 0.001〜50原子％，Ｂを0.0005〜0.01原子
％，Mgを0.0005〜0.01原子％，Ｃを0.0005〜0.01原子
％，Ｐを0.0005〜0.01原子％含有することが好ましい。
また、Pt，Pd，Au，Ag，Nb，Ｖ，Ti，Cr，Zr，Cu，Ｗお
よびMoのうちの１種を 0.001〜10原子％または２種以上
を合計 0.001〜10原子％含有することが好ましい。DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the composition of the ferromagnetic shape memory alloy of the present invention will be described. The ferromagnetic shape memory alloy of the present invention contains 35 to 65 atomic% of Co and 20 to 35 atomic% of Ga, with the balance being Ni and unavoidable impurities. Further Fe 0.001
0.001 to 30 atomic%, Mn 0.001 to 30 atomic%, In 0.001 to 50 atomic%, Si 0.001 to 50 atomic%, B 0.0005 to 0.01 atomic%, Mg 0.0005 to 0.01 atomic%, C 0.0005 to 0.01 Atomic% and P are preferably contained at 0.0005 to 0.01 atomic%.
In addition, one of Pt, Pd, Au, Ag, Nb, V, Ti, Cr, Zr, Cu, W and Mo should be contained in an amount of 0.001 to 10 atomic% or a total of two or more of 0.001 to 10 atomic%. Is preferred.
【００１５】Coは、Niとともに形状記憶特性および磁気
特性を向上させる元素である。しかし、Co含有量が35原
子％未満では強磁性を消失する。また、Co含有量が65原
子％を超えると形状記憶効果は発現しない。したがっ
て、Co含有量は35〜65原子％の範囲を満足する必要があ
る。Gaは、マルテンサイト変態温度およびキュリー温度
を変化させる元素であり、マルテンサイト変態温度およ
びキュリー温度を−200 〜 200℃の範囲で自在に制御で
きる。しかし、Ga含有量が20原子％未満ではマルテンサ
イト変態温度およびキュリー温度の制御効果が発揮され
ない。また、Ga含有量が35原子％を超えてもマルテンサ
イト変態温度およびキュリー温度の制御効果が発揮され
ない。したがって、Ga含有量は20〜35原子％の範囲を満
足する必要がある。Co is an element that improves shape memory characteristics and magnetic characteristics together with Ni. However, when the Co content is less than 35 atomic%, the ferromagnetism disappears. When the Co content exceeds 65 atomic%, the shape memory effect does not appear. Therefore, the Co content needs to satisfy the range of 35 to 65 atomic%. Ga is an element that changes the martensitic transformation temperature and the Curie temperature, and can freely control the martensitic transformation temperature and the Curie temperature in the range of -200 to 200 ° C. However, when the Ga content is less than 20 atomic%, the effects of controlling the martensitic transformation temperature and the Curie temperature are not exhibited. Further, even if the Ga content exceeds 35 atomic%, the effect of controlling the martensitic transformation temperature and the Curie temperature is not exhibited. Therefore, the Ga content needs to satisfy the range of 20 to 35 atomic%.
【００１６】Niは、Coとともに形状記憶特性を向上させ
る元素であり、Ni含有量が不足したり、あるいは過剰で
あると形状記憶効果は発現しない。したがって、上記し
た範囲内で含有されるCoおよびGaの残部をNiとする必要
がある。Feは、Ｂ２構造（いわゆるCeCl構造）のβ相の
存在領域を広げる元素であり、またＢ２構造のβ相を主
とする基地組織がマルテンサイト変態を生じる温度（以
下、マルテンサイト変態温度という）および磁気特性が
常磁性から強磁性に転移する温度（以下、キュリー温度
という）を変化させる元素である。しかし、Fe含有量が
0.001原子％未満ではＢ２構造のβ相の存在領域を広げ
る効果が発揮されない。また、Fe含有量が30原子％を超
えるとＢ２構造のβ相の存在領域を広げる効果が飽和す
る。したがって、Fe含有量は 0.001〜30原子％の範囲を
満足するのが好ましい。Ni is an element that improves shape memory characteristics together with Co. If the Ni content is insufficient or excessive, no shape memory effect is exhibited. Therefore, it is necessary to make the balance of Co and Ga contained in the above range Ni. Fe is an element that expands the existence region of a β phase having a B2 structure (a so-called CeCl structure), and a temperature at which a base structure mainly composed of a β phase having a B2 structure causes martensitic transformation (hereinafter, referred to as a martensitic transformation temperature). And an element that changes the temperature at which the magnetic properties change from paramagnetic to ferromagnetic (hereinafter referred to as the Curie temperature). However, the Fe content
If it is less than 0.001 atomic%, the effect of expanding the region where the β phase having the B2 structure is present cannot be exhibited. If the Fe content exceeds 30 atomic%, the effect of expanding the region where the β phase having the B2 structure is present is saturated. Therefore, the Fe content preferably satisfies the range of 0.001 to 30 atomic%.
【００１７】Mnは、Ｂ２構造のβ相の生成を促進する元
素であり、またマルテンサイト変態温度およびキュリー
温度を変化させる元素である。しかし、Mn含有量が 0.0
01原子％未満ではＢ２構造のβ相の存在領域を広げる効
果が発揮されない。また、Mn含有量が30原子％を超える
とＢ２構造のβ相の存在領域を広げる効果が飽和する。
したがって、Mn含有量は 0.001〜30原子％の範囲を満足
するのが好ましい。Mn is an element that promotes the formation of a β phase having a B2 structure and an element that changes the martensitic transformation temperature and the Curie temperature. However, when the Mn content is 0.0
If it is less than 01 atomic%, the effect of expanding the region where the β phase having the B2 structure is present cannot be exhibited. If the Mn content exceeds 30 atomic%, the effect of expanding the region where the β phase having the B2 structure is present is saturated.
Therefore, the Mn content preferably satisfies the range of 0.001 to 30 atomic%.
【００１８】Inは、Siとともに、マルテンサイト変態温
度およびキュリー温度を変化させる元素であり、Siとの
相乗効果によって、マルテンサイト変態温度およびキュ
リー温度を−200 〜 200℃の範囲で自在に制御できる。
しかし、In含有量が 0.001原子％未満ではマルテンサイ
ト変態温度およびキュリー温度の制御効果が発揮されな
い。また、In含有量が50原子％を超えてもマルテンサイ
ト変態温度およびキュリー温度の制御効果が発揮されな
い。したがって、In含有量は 0.001〜50原子％の範囲を
満足するのが好ましい。In is an element that changes the martensitic transformation temperature and the Curie temperature together with Si, and the martensitic transformation temperature and the Curie temperature can be freely controlled in the range of -200 to 200 ° C. by a synergistic effect with Si. .
However, when the In content is less than 0.001 atomic%, the control effects of the martensitic transformation temperature and the Curie temperature are not exhibited. Further, even if the In content exceeds 50 atomic%, the effect of controlling the martensitic transformation temperature and the Curie temperature is not exhibited. Therefore, the In content preferably satisfies the range of 0.001 to 50 atomic%.
【００１９】Siは、Inとともに、マルテンサイト変態温
度およびキュリー温度を変化させる元素であり、Inとの
相乗効果によって、マルテンサイト変態温度およびキュ
リー温度を−200 〜 200℃の範囲で自在に制御できる。
しかし、Si含有量が 0.001原子％未満ではマルテンサイ
ト変態温度およびキュリー温度の制御効果が発揮されな
い。また、Si含有量が50原子％を超えてもマルテンサイ
ト変態温度およびキュリー温度の制御効果が発揮されな
い。したがって、Si含有量は 0.001〜50原子％の範囲を
満足するのが好ましい。Si is an element that changes the martensitic transformation temperature and the Curie temperature together with In, and the martensitic transformation temperature and the Curie temperature can be freely controlled in the range of -200 to 200 ° C. by a synergistic effect with In. .
However, when the Si content is less than 0.001 atomic%, the effects of controlling the martensitic transformation temperature and the Curie temperature are not exhibited. Further, even if the Si content exceeds 50 atomic%, the effect of controlling the martensitic transformation temperature and the Curie temperature is not exhibited. Therefore, the Si content preferably satisfies the range of 0.001 to 50 atomic%.
【００２０】Ｂは、Mg，ＣやＰとともに、組織を微細化
し、材料の延性および形状記憶特性を向上させる元素で
ある。しかし、Ｂ含有量が0.0005原子％未満では組織の
微細化および材料の延性向上の効果が発揮されない。ま
た、Ｂ含有量が0.01原子％を超えると微細化および延性
向上の効果が飽和する。したがって、Ｂ含有量は0.0005
〜0.01原子％の範囲を満足するのが好ましい。B, together with Mg, C and P, is an element that refines the structure and improves the ductility and shape memory characteristics of the material. However, if the B content is less than 0.0005 atomic%, the effects of making the structure finer and improving the ductility of the material are not exhibited. If the B content exceeds 0.01 atomic%, the effects of miniaturization and improvement of ductility are saturated. Therefore, the B content is 0.0005
It preferably satisfies the range of 0.01 atomic%.
【００２１】Mgは、Ｂ，ＣやＰとともに、組織を微細化
し、材料の延性および形状記憶特性を向上させる元素で
ある。しかし、Mg含有量が0.0005原子％未満では組織の
微細化および延性向上の効果が発揮されない。また、Mg
含有量が0.01原子％を超えると微細化および延性向上の
効果が飽和する。したがって、Mg含有量は0.0005〜0.01
原子％の範囲を満足するのが好ましい。Mg, together with B, C and P, is an element that refines the structure and improves the ductility and shape memory characteristics of the material. However, when the Mg content is less than 0.0005 atomic%, the effects of making the structure finer and improving the ductility are not exhibited. Also, Mg
If the content exceeds 0.01 atomic%, the effect of miniaturization and improvement of ductility saturates. Therefore, Mg content is 0.0005-0.01
It is preferable to satisfy the range of atomic%.
【００２２】Ｃは、Ｂ，MgやＰとともに、組織を微細化
し、材料の延性および形状記憶特性を向上させる元素で
ある。しかし、Ｃ含有量が0.0005原子％未満では組織の
微細化および材料の延性向上の効果が発揮されない。ま
た、Ｃ含有量が0.01原子％を超えると微細化および延性
向上の効果が飽和する。したがって、Ｃ含有量は0.0005
〜0.01原子％の範囲を満足するのが好ましい。C, together with B, Mg and P, is an element that refines the structure and improves the ductility and shape memory characteristics of the material. However, if the C content is less than 0.0005 atomic%, the effects of making the structure finer and improving the ductility of the material are not exhibited. If the C content exceeds 0.01 atomic%, the effects of miniaturization and improvement of ductility are saturated. Therefore, the C content is 0.0005
It preferably satisfies the range of 0.01 atomic%.
【００２３】Ｐは、Ｂ，MgやＣとともに、組織を微細化
し、材料の延性および形状記憶特性を向上させる元素で
ある。しかし、Ｐ含有量が0.0005原子％未満では組織の
微細化および材料の延性向上の効果が発揮されない。ま
た、Ｐ含有量が0.01原子％を超えると微細化および延性
向上の効果が飽和する。したがって、Ｐ含有量は0.0005
〜0.01原子％の範囲を満足するのが好ましい。P, together with B, Mg and C, is an element that refines the structure and improves the ductility and shape memory characteristics of the material. However, if the P content is less than 0.0005 atomic%, the effects of miniaturizing the structure and improving the ductility of the material are not exhibited. If the P content exceeds 0.01 atomic%, the effects of miniaturization and improvement of ductility are saturated. Therefore, the P content is 0.0005
It preferably satisfies the range of 0.01 atomic%.
【００２４】Pt，Pd，Au，Ag，Nb，Ｖ，Ti，Cr，Zr，C
u，ＷおよびMoは、いずれもマルテンサイト変態温度や
キュリー温度を変化させるだけでなく、組織を微細化
し、材料の延性を向上させる元素である。しかし、これ
らの元素が 0.001原子％未満では組織の微細化および材
料の延性向上の効果が発揮されない。また、これらの元
素が10原子％を超えると微細化および延性の向上効果が
飽和する。したがって、これらの元素を１種添加する場
合は、その含有量は 0.001〜10原子％の範囲を満足し、
２種以上添加する場合は、その含有量は合計 0.001〜10
原子％の範囲を満足するのが好ましい。Pt, Pd, Au, Ag, Nb, V, Ti, Cr, Zr, C
u, W and Mo are elements that not only change the martensitic transformation temperature and Curie temperature, but also refine the structure and improve the ductility of the material. However, when these elements are less than 0.001 atomic%, the effects of making the structure finer and improving the ductility of the material are not exhibited. On the other hand, when these elements exceed 10 atomic%, the effects of miniaturization and improvement of ductility are saturated. Therefore, when one of these elements is added, its content satisfies the range of 0.001 to 10 atomic%,
When two or more kinds are added, the total content is 0.001 to 10
It is preferable to satisfy the range of atomic%.
【００２５】次に本発明の強磁性形状記憶合金の組織に
ついて説明する。本発明の強磁性形状記憶合金は、Ｂ２
構造（いわゆるCeCl構造）のβ相からなる単相組織を有
するか、またはＢ２構造のβ相とｆｃｃ構造の第２相か
らなる２相組織を有する。単相組織を有する場合は、単
結晶であっても良いし、あるいは多結晶であっても良
い。ただし単結晶の方が、形状記憶特性や磁気特性が優
れているので好ましい。本発明においては、単結晶を得
る方法は特定の方法に限定せず、チョクラルスキー法等
の従来から知られている方法を用いれば良い。Next, the structure of the ferromagnetic shape memory alloy of the present invention will be described. The ferromagnetic shape memory alloy of the present invention has a B2
It has a single-phase structure composed of a β phase having a structure (a so-called CeCl structure), or has a two-phase structure composed of a β phase having a B2 structure and a second phase having an fcc structure. When it has a single phase structure, it may be a single crystal or a polycrystal. However, a single crystal is preferable because it has excellent shape memory characteristics and magnetic characteristics. In the present invention, the method for obtaining a single crystal is not limited to a specific method, and a conventionally known method such as the Czochralski method may be used.
【００２６】２相組織は、単相組織に比べて延性，形状
記憶特性および磁気特性が著しく向上するので一層好ま
しい。２相組織の第２相は、ｆｃｃ構造を有するＡ１構
造のγ相および／またはＬ１2 構造のγ’相および／ま
たはｈｃｐ構造のε−Ｃ0 相であることが好ましい。た
だし第２相の体積分率が0.01体積％未満では形状記憶特
性や磁気特性の向上効果が発揮されない。また、第２相
の体積分率が80体積％を超えると形状記憶特性や磁気特
性の向上効果が飽和する。したがって、第２相の体積分
率は0.01〜80体積％の範囲を満足するのが好ましい。The two-phase structure is more preferable because the ductility, shape memory characteristics and magnetic characteristics are remarkably improved as compared with the single-phase structure. The second phase of the two-phase structure is preferably a epsilon-C 0-phase A1 gamma phase structure and / or L1 2 gamma structures' phase and / or hcp structure having an fcc structure. However, when the volume fraction of the second phase is less than 0.01% by volume, the effect of improving shape memory characteristics and magnetic characteristics is not exhibited. On the other hand, when the volume fraction of the second phase exceeds 80% by volume, the effect of improving shape memory properties and magnetic properties is saturated. Therefore, the volume fraction of the second phase preferably satisfies the range of 0.01 to 80% by volume.
【００２７】本発明の強磁性形状記憶合金を製造する場
合は、溶湯を凝固させて 500〜1400℃で熱処理を行なっ
た後、焼入れを行なう。こうしてβ相と第２相（すなわ
ちγ相および／またはγ’相）との２相組織が得られる
ので、その後、所定の形状に加工する際に優れた延性を
発揮するのである。焼入れした後、さらに冷間圧延また
は熱間圧延を行なって板材とした後、所定の形状に加工
し、 500〜1400℃で再結晶熱処理を行なうことによっ
て、形状記憶機能を付与されたＢ２構造のβ相からなる
単相組織の強磁性形状記憶合金が得られる。When manufacturing the ferromagnetic shape memory alloy of the present invention, the molten metal is solidified, heat-treated at 500 to 1400 ° C., and then quenched. In this way, a two-phase structure of the β phase and the second phase (that is, the γ phase and / or the γ ′ phase) is obtained, and then, when processed into a predetermined shape, excellent ductility is exhibited. After quenching, further cold rolling or hot rolling is performed to obtain a sheet material, then processed into a predetermined shape, and subjected to a recrystallization heat treatment at 500 to 1400 ° C., thereby providing a B2 structure having a shape memory function. A ferromagnetic shape memory alloy having a single phase structure consisting of β phase is obtained.
【００２８】この単相組織の強磁性形状記憶合金を、さ
らに 300〜1400℃で熱処理してβ相の結晶粒界にγ相お
よび／またはγ’相および／またはε−Ｃ0 相を優先的
に析出させることによって、形状記憶機能を付与された
Ｂ２構造のβ相と延性に優れたｆｃｃ構造の第２相（す
なわちγ相および／またはγ’相）からなる２相組織の
強磁性形状記憶合金が得られる。The ferromagnetic shape memory alloy having the single phase structure is further heat-treated at 300 to 1400 ° C., so that the γ phase and / or γ ′ phase and / or ε-C 0 phase are preferentially formed at the β phase crystal grain boundary. The ferromagnetic shape memory of a two-phase structure composed of a β phase having a B2 structure provided with a shape memory function and a second phase having an fcc structure having excellent ductility (that is, a γ phase and / or a γ ′ phase) by precipitation An alloy is obtained.
【００２９】[0029]
【実施例】表１に示す成分の合金を溶製した後、凝固さ
せて、 500〜1400℃で熱処理を行ない、さらに焼入れお
よび冷間圧延を施した後、所定の大きさの板材を切り出
して 500〜1400℃で再結晶化熱処理を行ない、形状記憶
機能を付与された多結晶のβ相（Ｂ２構造）の強磁性形
状記憶合金を製造した。これを発明例１および発明例２
とする。EXAMPLE An alloy having the composition shown in Table 1 was melted, solidified, heat-treated at 500-1400 ° C., quenched and cold-rolled, and a sheet material having a predetermined size was cut out. A recrystallization heat treatment was performed at 500 to 1400 ° C. to produce a polycrystalline β-phase (B2 structure) ferromagnetic shape memory alloy having a shape memory function. This is referred to as Invention Example 1 and Invention Example 2
And
【００３０】発明例３および発明例４は、発明例１，発
明例２と同様の方法で多結晶のβ相を生成させた後、さ
らに歪み焼なましによって単結晶のβ相（Ｂ２構造）の
強磁性形状記憶合金を製造した例である。発明例５およ
び発明例６は、発明例１，発明例２と同様の方法で多結
晶のβ相を生成させた後、さらに 500〜1350℃で熱処理
してβ相の結晶粒界にγ相および／またはγ’相を析出
させて、形状記憶機能を付与されたＢ２構造のβ相と延
性に優れたｆｃｃ構造の第２相（すなわちγ相および／
またはγ’相）との２相組織の強磁性形状記憶合金を製
造した例である。発明例５の第２相の体積分率は10体積
％であり、発明例６の第２相の体積分率は40体積％であ
った。In Inventive Examples 3 and 4, a polycrystalline β phase was formed in the same manner as in Inventive Examples 1 and 2, and then a single crystal β phase (B2 structure) was formed by strain annealing. This is an example of manufacturing a ferromagnetic shape memory alloy of the present invention. Inventive Example 5 and Inventive Example 6 produce a polycrystalline β phase in the same manner as Inventive Example 1 and Inventive Example 2, and then heat-treated at 500 to 1350 ° C. to form a γ phase And / or a γ ′ phase is precipitated to form a β phase having a B2 structure having a shape memory function and a second phase having an fcc structure having excellent ductility (that is, γ phase and / or
Or a γ ′ phase). The volume fraction of the second phase of Invention Example 5 was 10% by volume, and the volume fraction of the second phase of Invention Example 6 was 40% by volume.
【００３１】比較例１はCoの含有量が本発明の範囲を外
れる例であり、比較例２はGaの含有量が本発明の範囲を
外れる例である。比較例１は、発明例１，発明例２と同
様の方法で多結晶β相を生成させた。比較例２は、発明
例５，発明例６と同様の方法でβ相と第２相との２相組
織を生成させた。比較例２の第２相の体積分率は90体積
％であった。Comparative Example 1 is an example in which the content of Co is out of the range of the present invention, and Comparative Example 2 is an example in which the content of Ga is out of the range of the present invention. In Comparative Example 1, a polycrystalline β phase was produced in the same manner as in Inventive Examples 1 and 2. In Comparative Example 2, a two-phase structure of a β phase and a second phase was formed in the same manner as in Inventive Examples 5 and 6. The volume fraction of the second phase in Comparative Example 2 was 90% by volume.
【００３２】[0032]
【表１】 [Table 1]
【００３３】発明例１〜６および比較例１〜２について
形状記憶特性および磁歪特性を調査した。また冷間圧延
率についても調査した。その結果を表２に示す。形状記
憶特性は、50mm×５mm×0.3mm の帯状の試験片を切り出
し、曲げ試験を行なって２％曲げ歪を加えたときの回復
率を測定した。磁歪特性は、単結晶β相である発明例３
〜４および比較例２については、図１に示すように、寸
法５mm×５mm×５mmの試験片を切り出し、（１１０）面
にストレンゲージ２を装着して、強さ30Ａ／ｍの磁界Ｈ
を［００１］方向に印加して、歪み量を測定した。β相
と第２相（すなわちγ相および／またはγ’相）との２
相組織である発明例５，６および比較例３については、
30mm×10mm×１mmの帯状の試験片を用い、圧延方向に平
行な向きに磁場を加えたときの圧延方向の歪み量を測定
した。Shape memory characteristics and magnetostriction characteristics of Inventive Examples 1 to 6 and Comparative Examples 1 and 2 were investigated. The cold rolling reduction was also investigated. Table 2 shows the results. The shape memory characteristics were obtained by cutting a strip of 50 mm × 5 mm × 0.3 mm and performing a bending test to measure a recovery rate when a 2% bending strain was applied. Inventive Example 3 in which the magnetostrictive property is a single crystal β phase
As shown in FIG. 1, a test piece having a size of 5 mm × 5 mm × 5 mm was cut out, a strain gauge 2 was attached to the (110) plane, and a magnetic field H having a strength of 30 A / m was obtained.
Was applied in the [001] direction, and the amount of strain was measured. 2 of the β phase and the second phase (ie, γ phase and / or γ ′ phase)
For Invention Examples 5 and 6 and Comparative Example 3 which are phase structures,
Using a strip-shaped test piece of 30 mm × 10 mm × 1 mm, the amount of strain in the rolling direction when a magnetic field was applied in a direction parallel to the rolling direction was measured.
【００３４】なお形状記憶特性の回復率（％）は下記の
(1)式で算出される値であり、磁歪特性（％）は下記の
(2)式で算出される値であり、冷間圧延率（％）は下記
の (3)式で算出される値である。 形状記憶特性の回復率（％） ＝ 100×｛（εd −εr ）／εd ｝ ・・・ (1) εd ：変形させた後の表面歪み εr ：回復させた時の表面歪み 磁歪特性（％）＝ 100×｛（Ｌ2 −Ｌ1 ）／Ｌ1 ｝ ・・・ (2) Ｌ1 ：磁場印加前の長さ（mm） Ｌ2 ：磁場印加後の長さ（mm） 冷間圧延率（％）＝ 100×｛（ｔ1 −ｔ2 ）／ｔ1 ｝ ・・・ (3) ｔ1 ：冷間圧延前の厚さ（mm） ｔ2 ：冷間圧延後の厚さ（mm）The recovery rate (%) of the shape memory characteristic is as follows.
It is a value calculated by the equation (1), and the magnetostriction characteristic (%) is
This is a value calculated by the formula (2), and the cold rolling reduction (%) is a value calculated by the following formula (3). Recovery rate of shape memory characteristics (%) = 100 × ｛(ε d −ε r ) / ε d・ ・ ・ (1) ε d : surface strain after deformation ε r : surface strain when recovered Magnetostrictive property (%) = 100 × {(L 2 −L 1 ) / L 1 } (2) L 1 : length before application of magnetic field (mm) L 2 : length after application of magnetic field (mm) Cold rolling ratio (%) = 100 × {(t 1 −t 2 ) / t 1 } (3) t 1 : thickness before cold rolling (mm) t 2 : thickness after cold rolling Sa (mm)
【００３５】[0035]
【表２】 [Table 2]
【００３６】表２から明らかなように、発明例１〜６と
比較例１〜３を比べると、発明例の方が、形状記憶特性
の回復率，磁歪特性および冷間圧延率に優れた形状記憶
合金を得ることができた。また発明例１〜６のうち、単
結晶β相の単相組織（発明例３，４）やβ相と第２相と
の２相組織（発明例５，６）にすることによって、多結
晶β相の単相組織（発明例１，２）に比べて、形状記憶
特性の回復率，磁歪特性および冷間圧延率が一層優れた
強磁性形状記憶合金を得ることができた。As is clear from Table 2, when the invention examples 1 to 6 are compared with the comparative examples 1 to 3, the shape of the invention example is more excellent in the recovery rate of the shape memory property, the magnetostriction property and the cold rolling rate. A memory alloy was obtained. In addition, among the invention examples 1 to 6, the polycrystalline single-phase structure of the single crystal β phase (invention examples 3 and 4) and the two-phase structure of the β phase and the second phase (invention examples 5 and 6) make it possible to obtain polycrystal. Compared with the single phase structure of β phase (Inventive Examples 1 and 2), a ferromagnetic shape memory alloy having more excellent shape memory recovery rate, magnetostriction property and cold rolling reduction was obtained.
【００３７】また、特に加工性能に優れた（すなわち冷
間圧延率の高い）発明例６や、形状記憶特性の回復率お
よび磁歪特性に優れた発明例５のように、添加元素の種
類と添加量を適切に選択することによって、目的や用途
に応じた性能を有する強磁性形状記憶合金を得ることが
可能である。Further, as shown in Invention Example 6 which is particularly excellent in processing performance (that is, high in cold rolling ratio) and Invention Example 5 in which the recovery rate of shape memory characteristics and magnetostriction characteristics are excellent, the type of additive element and By appropriately selecting the amount, it is possible to obtain a ferromagnetic shape memory alloy having performance according to the purpose and application.
【００３８】[0038]
【発明の効果】本発明では、延性に優れ、強磁性を有
し、かつマルテンサイト変態を生じる強磁性形状記憶合
金を得ることができる。According to the present invention, it is possible to obtain a ferromagnetic shape memory alloy having excellent ductility, having ferromagnetism, and causing martensitic transformation.
【図１】試験片の方位と磁界の方向を示す斜視図であ
る。FIG. 1 is a perspective view showing the orientation of a test piece and the direction of a magnetic field.
１ 試験片 ２ ストレンゲージ 1 Test piece 2 Strain gauge
───────────────────────────────────────────────────── フロントページの続き (72)発明者 貝沼 亮介 宮城県名取市倉田字堰根172−15 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Ryosuke Kainuma
Claims (8)
有し、残部がNiおよび不可避的不純物からなる組成と、
Ｂ２構造のβ相からなる単相組織またはＢ２構造のβ相
とｆｃｃ構造の第２相からなる２相組織とを有すること
を特徴とする強磁性形状記憶合金。1. A composition containing 35 to 65 atomic% of Co and 20 to 35 atomic% of Ga, with the balance being Ni and unavoidable impurities,
A ferromagnetic shape memory alloy having a single phase structure composed of a B2 structure β phase or a two phase structure composed of a B2 structure β phase and an fcc structure second phase.
％および／またはMnを 0.001〜30原子％含有することを
特徴とする請求項１に記載の強磁性形状記憶合金。2. The ferromagnetic shape memory alloy according to claim 1, further comprising 0.001 to 30 atomic% of Fe and / or 0.001 to 30 atomic% of Mn in addition to the composition.
１種を 0.001〜50原子％または２種を合計 0.001〜50原
子％含有することを特徴とする請求項１または２に記載
の強磁性形状記憶合金。3. The method according to claim 1, wherein in addition to the composition, one of In and Si is contained in an amount of 0.001 to 50 at% or a total of 0.001 to 50 at%. Ferromagnetic shape memory alloy.
子％、Mgを0.0005〜0.01原子％、Ｃを0.0005〜0.01原子
％およびＰを0.0005〜0.01原子％のうちの１種または２
種以上含有することを特徴とする請求項１、２または３
に記載の強磁性形状記憶合金。4. In addition to the above composition, one or two of 0.0005 to 0.01 atomic% of B, 0.0005 to 0.01 atomic% of Mg, 0.0005 to 0.01 atomic% of C, and 0.0005 to 0.01 atomic% of P.
4. The composition according to claim 1, wherein the content is at least one species.
2. The ferromagnetic shape memory alloy according to item 1.
b、Ｖ、Ti、Cr、Zr、Cu、ＷおよびMoのうちの１種を 0.
001〜10原子％または２種以上を合計 0.001〜10原子％
含有することを特徴とする請求項１、２、３または４に
記載の強磁性形状記憶合金。5. In addition to the above composition, Pt, Pd, Au, Ag, N
b, V, Ti, Cr, Zr, Cu, W, and Mo.
001 to 10 atomic% or a total of two or more types 0.001 to 10 atomic%
5. The ferromagnetic shape memory alloy according to claim 1, wherein the ferromagnetic shape memory alloy is contained.
とする請求項１、２または３に記載の強磁性形状記憶合
金。6. The ferromagnetic shape memory alloy according to claim 1, wherein the single phase structure is a single crystal.
のγ相および／またはＬ１2 構造のγ’相および／また
はｈｃｐ構造のε−Ｃ0 相であることを特徴とする請求
項１、２、３、４または５に記載の強磁性形状記憶合
金。7. The second phase of the two-phase structure is a γ phase having an A1 structure and / or a γ ′ phase having an L1 2 structure and / or an ε-C 0 phase having an hcp structure. Item 7. The ferromagnetic shape memory alloy according to item 1, 2, 3, 4, or 5.
0.01〜80体積％の範囲を満足することを特徴とする請求
項１、２、３、４、５または７に記載の強磁性形状記憶
合金。8. The volume fraction of the second phase in the two-phase structure is
The ferromagnetic shape memory alloy according to claim 1, wherein the ferromagnetic shape memory alloy satisfies a range of 0.01 to 80% by volume.
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| JP2001118315A JP2002317235A (en) | 2001-04-17 | 2001-04-17 | Ferromagnetic shape memory alloy |
| PCT/JP2001/006864 WO2002014565A1 (en) | 2000-08-14 | 2001-08-09 | Ferromagnetic shape-memory alloy |
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|---|---|---|---|
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1460139A1 (en) * | 2003-03-18 | 2004-09-22 | HONDA MOTOR CO., Ltd. | Co-Ni-Al Shape memory alloy and method for producing same |
| JP2009235454A (en) * | 2008-03-26 | 2009-10-15 | Toyota Central R&D Labs Inc | Ferromagnetic shape-memory alloy, and method for manufacturing sintered compact of ferromagnetic shape-memory alloy |
| CN117535560A (en) * | 2023-10-13 | 2024-02-09 | 哈尔滨理工大学 | Large-elastic thermal effect polycrystalline Co-V-Ga-Ti memory alloy and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03219037A (en) * | 1989-10-03 | 1991-09-26 | Taiji Nishizawa | Ni base shape memory alloy and its manufacture |
| JPH04163817A (en) * | 1990-10-26 | 1992-06-09 | Furukawa Electric Co Ltd:The | Magnetic and temperature switching mechanism |
| JP2001279357A (en) * | 2000-03-29 | 2001-10-10 | Toshiba Corp | Magnetic shape memory alloy |
| JP2001279360A (en) * | 2000-03-30 | 2001-10-10 | Toshiba Corp | Mn SERIES ALLOY |
-
2001
- 2001-04-17 JP JP2001118315A patent/JP2002317235A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03219037A (en) * | 1989-10-03 | 1991-09-26 | Taiji Nishizawa | Ni base shape memory alloy and its manufacture |
| JPH04163817A (en) * | 1990-10-26 | 1992-06-09 | Furukawa Electric Co Ltd:The | Magnetic and temperature switching mechanism |
| JP2001279357A (en) * | 2000-03-29 | 2001-10-10 | Toshiba Corp | Magnetic shape memory alloy |
| JP2001279360A (en) * | 2000-03-30 | 2001-10-10 | Toshiba Corp | Mn SERIES ALLOY |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1460139A1 (en) * | 2003-03-18 | 2004-09-22 | HONDA MOTOR CO., Ltd. | Co-Ni-Al Shape memory alloy and method for producing same |
| US7371295B2 (en) | 2003-03-18 | 2008-05-13 | Honda Motor Co., Ltd. | Shape memory alloy and method for producing same |
| JP2009235454A (en) * | 2008-03-26 | 2009-10-15 | Toyota Central R&D Labs Inc | Ferromagnetic shape-memory alloy, and method for manufacturing sintered compact of ferromagnetic shape-memory alloy |
| CN117535560A (en) * | 2023-10-13 | 2024-02-09 | 哈尔滨理工大学 | Large-elastic thermal effect polycrystalline Co-V-Ga-Ti memory alloy and preparation method thereof |
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