JP2005226126A - Vibration-proofing alloy - Google Patents
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Abstract
Description
本発明は、自動車、電機、産業機械等から発生する種々の騒音、振動対策の一助として使用される防振合金の内、高い振動減衰能と優れた冷間加工性を兼備した防振合金に関するものである。 The present invention relates to an anti-vibration alloy having high vibration damping ability and excellent cold workability among anti-vibration alloys used as an aid for countermeasures against various noises and vibrations generated from automobiles, electric machines, industrial machines, etc. Is.
自動車、電機、産業機械等の様々な工業分野で、騒音や振動が重要視されている。特に自動車分野においては、環境への配慮と運転時の快適性の追求から、静かで乗り心地の良い車が求められている。このような騒音や振動の発生を嫌う分野においては、従来、振動減衰能の高い防振材料が好んで用いられている。この防振材料は、振動や音を吸収する能力に優れた材料である。 Noise and vibration are regarded as important in various industrial fields such as automobiles, electric machines, and industrial machines. In the automobile field in particular, a car that is quiet and comfortable is demanded from the consideration of the environment and the pursuit of driving comfort. In the field where generation of such noise and vibration is disliked, conventionally, a vibration isolating material having a high vibration damping ability is preferably used. This anti-vibration material is a material having an excellent ability to absorb vibration and sound.
実用的な防振材料としては、変態双晶の存在により高い減衰能が得られるＭｎ−Ｃｕ系双晶型防振合金、２枚の鋼板の間に軟らかい樹脂を挟んだ制振鋼板、軟磁性合金の磁気−機械ヒステリシスにより振動を吸収する強磁性型防振合金が知られている（例えば、非特許文献１参照）。
この内、Ｍｎ−Ｃｕ系双晶型合金や制振鋼板は、１００℃以上の高温域では振動減衰能が低下するのに対し、強磁性型防振合金は、３００℃程度の高温域まで高い減衰能を示すことから、使用中に温度上昇が起こるエンジンや各種モータ周辺の防振部材として好んで使用される。
Practical anti-vibration materials include Mn-Cu twin-type anti-vibration alloys that can obtain high damping ability due to the presence of transformation twins, damping steel plates with soft resin sandwiched between two steel plates, soft magnetic materials There is known a ferromagnetic anti-vibration alloy that absorbs vibration by the magneto-mechanical hysteresis of the alloy (see, for example, Non-Patent Document 1).
Among these, Mn—Cu twin-type alloys and vibration-damping steel sheets have reduced vibration damping performance at high temperatures of 100 ° C. or higher, whereas ferromagnetic anti-vibration alloys have high temperatures up to about 300 ° C. Since it exhibits a damping capacity, it is preferably used as a vibration isolator around engines and various motors where temperature rises during use.
強磁性型防振合金における振動減衰機構は、非特許文献１に示されるように、図１を用いて説明できる。一般に、金属の弾性限内での応力−歪曲線は、フックの法則に従い、応力増加に伴って直線的な歪量を示す。
しかしながら、強磁性体の場合には、応力付与に伴う磁壁の移動によって磁歪が生じるので、応力増加に伴う機械的な歪１と併せて磁歪２が加わる。そのため、弾性限内での応力−歪曲線は、図１に示すように直線関係からのずれが生じる。磁歪が図１のＳ点で飽和すると、更に応力を高めても磁歪は変化しないので（以下、Ｓ点以上の応力での磁歪を飽和磁歪定数λｓと呼ぶ）、機械的な歪だけが増加する。
As shown in Non-Patent Document 1, the vibration damping mechanism in the ferromagnetic vibration-proof alloy can be explained with reference to FIG. In general, a stress-strain curve within the elastic limit of a metal shows a linear strain amount as the stress increases according to Hooke's law.
However, in the case of a ferromagnetic material, magnetostriction is generated by the movement of the domain wall accompanying the application of stress, so that the magnetostriction 2 is added together with the mechanical strain 1 accompanying the increase in stress. Therefore, the stress-strain curve within the elastic limit deviates from the linear relationship as shown in FIG. When the magnetostriction is saturated at the S point in FIG. 1, the magnetostriction does not change even if the stress is further increased (hereinafter, the magnetostriction at the stress of the S point or higher is referred to as a saturated magnetostriction constant λ s ), so only the mechanical strain increases. To do.
ここで、応力によって移動した磁壁は、応力をゼロに戻しても、元の状態には戻らない。これは、磁場を印加することによって移動した磁壁が、磁場をゼロに戻しても元の状態に戻らず磁気的なヒステリシス現象を示すことと同じである。それ故、弾性限内のＳ点より高い応力から、応力をゼロに戻すと、微小なひずみＡが残留する。図１のＯＳＡで囲まれる面積が、磁気−機械ヒステリシス３と呼ばれるエネルギー量に相当する。
この磁気−機械ヒステリシス３は、応力付与→応力除去の１サイクル中に材料が吸収したエネルギーであり、振動減衰量に相当する。振動減衰量が高い材料ほど、優れた防振合金と言える。
Here, the domain wall moved by the stress does not return to the original state even if the stress is returned to zero. This is the same as the domain wall moved by applying the magnetic field does not return to the original state even when the magnetic field is returned to zero, and exhibits a magnetic hysteresis phenomenon. Therefore, when the stress is returned to zero from a stress higher than the S point within the elastic limit, a minute strain A remains. The area surrounded by OSA in FIG. 1 corresponds to an energy amount called magneto-mechanical hysteresis 3.
The magneto-mechanical hysteresis 3 is energy absorbed by the material during one cycle of applying stress to removing stress, and corresponds to vibration attenuation. It can be said that the higher the vibration damping amount, the better the vibration-proof alloy.
強磁性型防振合金の具体例として、特許文献１には、質量％でＡｌ：１〜８％、Ｃｒ：２〜３０％、Ｓｉ：０．５％以下、Ｍｎ：１％以下、残部Ｆｅと不可避不純物から成る防振合金が提案されている。この提案は、Ｆｅ−Ｃｒ−Ａｌ系を基本組成とする合金が、適度な振動減衰能を示すとともに、耐食性と適度な機械的強度も兼ね備えた合金である。
また、特許文献２には、質量％で４０％を超え６０％未満のＣｏを含むＦｅ−Ｃｏ系防振合金や、これにＶ：３％以下、Ｎｂ：２％以下、Ｔａ：１％以下を含有させた防振合金が提案されている。この提案は、極めて高い振動減衰能が得られるという点で優れた防振合金である。
As a specific example of the ferromagnetic anti-vibration alloy, Patent Document 1 includes, in mass%, Al: 1 to 8%, Cr: 2 to 30%, Si: 0.5% or less, Mn: 1% or less, and the balance Fe. Anti-vibration alloys composed of inevitable impurities have been proposed. This proposal is an alloy in which an Fe—Cr—Al-based alloy has an appropriate vibration damping ability and also has corrosion resistance and appropriate mechanical strength.
Patent Document 2 discloses an Fe-Co vibration-proof alloy containing Co in excess of 40% by mass and less than 60% by mass, V: 3% or less, Nb: 2% or less, Ta: 1% or less. An anti-vibration alloy containing bismuth has been proposed. This proposal is an anti-vibration alloy excellent in that a very high vibration damping ability can be obtained.
また、非特許文献２には、Ｆｅ−Ｃｏ系合金の平衡状態図が記載されている。この平衡状態図によれば、質量％でＣｏ量が２６．０〜７２．０％の範囲では、７３０℃以下の低温域に脆弱な規則相が存在する。それ故、上述の特許文献２に開示される質量％で４０％を超え６０％未満のＣｏを含むＦｅ−Ｃｏ系防振合金は、室温では脆弱な規則相で構成されている。
また、非特許文献３には、質量％で約４９％のＣｏを含む脆弱なＦｅ−Ｃｏ系合金の工業的な製造方法が記載されている。非特許文献３によれば、冷間圧延を行う前に、該合金を９２５〜１０５０℃の範囲に加熱保持後、４℃の食塩水または水に急冷する工程が必要である。これは、熱処理温度（９２５〜１０５０℃）から室温以下まで急冷することにより、脆弱な規則相が出現する前に、合金の冷却を完了させ、規則化を起こさずに冷間圧延できるようにすることを目指した方法である。
Non-Patent Document 2 describes an equilibrium diagram of an Fe—Co alloy. According to this equilibrium diagram, a fragile ordered phase exists in a low temperature range of 730 ° C. or lower in the range of 2% by mass to 26.0% by mass%. Therefore, the Fe—Co anti-vibration alloy containing Co of more than 40% and less than 60% by mass disclosed in the above-mentioned Patent Document 2 is composed of a brittle ordered phase at room temperature.
Non-Patent Document 3 describes an industrial production method of a fragile Fe-Co alloy containing about 49% Co by mass%. According to Non-Patent Document 3, before cold rolling, a process of heating and holding the alloy in the range of 925 to 1050 ° C. and then rapidly cooling to 4 ° C. saline or water is required. This is because by rapidly cooling from a heat treatment temperature (925 to 1050 ° C.) to room temperature or lower, cooling of the alloy is completed before a brittle ordered phase appears, and cold rolling can be performed without causing ordering. It is a method aimed at.
上述した特許文献１に開示されるＦｅ−Ｃｒ−Ａｌ系を基本組成とする防振合金は、耐食性や適度な機械的特性を兼ね備えているという点では有利であるものの、振動減衰能は、防振合金として効果的なレベルに満たないことが多い。それ故、実用化のためには振動減衰能を更に高める必要がある。
また、特許文献２に開示される４０％を超え６０％未満のＣｏを含むＦｅ−Ｃｏ系防振合金は、実用に十分供することのできる高い振動減衰能が得られるものの、脆弱な規則相が出現するために冷間加工性が著しく悪い。
The anti-vibration alloy based on the Fe—Cr—Al system disclosed in Patent Document 1 described above is advantageous in that it has corrosion resistance and appropriate mechanical properties, but the vibration damping ability is Often less than effective level as a vibration alloy. Therefore, it is necessary to further increase the vibration damping capability for practical use.
Moreover, although the Fe-Co-type vibration-proof alloy containing Co exceeding 40% and less than 60% disclosed in Patent Document 2 has a high vibration damping ability that can be sufficiently used for practical use, it has a fragile ordered phase. Since it appears, cold workability is remarkably bad.
そのため、例えば、厚さ２ｍｍ以下の様な冷間圧延工程が必要な薄い板厚の防振合金を製造する場合には、非特許文献３に記載される様な熱処理後の急冷工程が必要となる。このような急冷工程を行うと、製造工数の増大と製造費の上昇を招くので、防振合金を実用化する上での大きな問題となる。そのため、特許文献２に開示される防振合金の振動減衰能を若干犠牲にしてでも、急冷工程を行わなくても冷間加工のできる防振合金が望まれている。
本発明の目的は、上述の課題を解決し、振動減衰能と冷間加工性を兼備し、実用に適した防振合金を提供することである。
Therefore, for example, in the case of producing a thin vibration-proof alloy that requires a cold rolling process having a thickness of 2 mm or less, a rapid cooling process after heat treatment as described in Non-Patent Document 3 is required. Become. When such a rapid cooling process is performed, the manufacturing man-hour and the manufacturing cost increase are caused, which is a serious problem in putting the vibration-proof alloy into practical use. Therefore, there is a demand for a vibration-proof alloy that can be cold-worked without performing a rapid cooling process even if the vibration damping ability of the vibration-proof alloy disclosed in Patent Document 2 is slightly sacrificed.
An object of the present invention is to solve the above-mentioned problems and to provide a vibration-proof alloy suitable for practical use that has both vibration damping ability and cold workability.
図１から分かるように、強磁性型防振合金の振動減衰能は、防振合金の飽和磁歪定数λｓと関係している。また、振動減衰をさせるためには、応力付与によって磁壁が移動することが重要である。それ故、振動減衰能は、飽和磁歪定数λｓとともに磁壁移動のし易さ、すなわち防振合金の軟磁性や組織形態とも関係している。 As can be seen from FIG. 1, the vibration damping capacity of the ferromagnetic anti-vibration alloy is related to the saturation magnetostriction constant λ s of the anti-vibration alloy. Further, in order to attenuate vibration, it is important that the domain wall moves by applying stress. Therefore, the vibration damping capacity is related to the saturation magnetostriction constant λ s and the ease of domain wall movement, that is, the soft magnetism and the structure of the vibration-proof alloy.
本発明者は、特許文献１に開示されるＦｅ−Ｃｒ−Ａｌ系を基本組成とする防振合金と特許文献２に開示される４０％を超え６０％未満のＣｏを含むＦｅ−Ｃｏ系防振合金の振動減衰能の差が、両者の飽和磁歪定数λｓの差に起因することを突き止めた。そして、Ｆｅ−Ｃｏ系防振合金のＣｏ含有量を調整することにより、規則化する領域外でも高い飽和磁歪定数、ひいては高い振動減衰能をもった防振合金が得られることを見出した。
更には、このＣｏ量の調整により、Ｆｅ−Ｃｏ系防振合金の冷間加工性を大きく改善できることを見出し、本発明に到達した。また、磁壁移動の容易な軟磁性とするために、Ｃｏ以外の元素の適正範囲と適正な組織形態を見出し、本発明に到達した。
The inventor has disclosed an anti-vibration alloy based on an Fe—Cr—Al system disclosed in Patent Document 1 and an Fe—Co system anti-corrosion disclosed in Patent Document 2 containing more than 40% and less than 60% Co. It was found that the difference in vibration damping ability of the vibration alloy is caused by the difference between the saturation magnetostriction constants λ s of both. Then, it has been found that by adjusting the Co content of the Fe—Co vibration-proof alloy, a vibration-proof alloy having a high saturation magnetostriction constant and thus a high vibration damping ability can be obtained even outside the region to be ordered.
Furthermore, it has been found that the cold workability of the Fe—Co vibration-proof alloy can be greatly improved by adjusting the amount of Co, and the present invention has been achieved. In addition, in order to achieve soft magnetism with easy domain wall movement, an appropriate range of elements other than Co and an appropriate structure form have been found, and the present invention has been achieved.
すなわち本発明は、質量％でＣ：０．１０％以下（０を含む）、Ｓｉ：０．０１〜３．５０％、Ｍｎ：０．０１〜２．０％、Ｃｏ：５．０〜２６．０％未満、Ａｌ：３．５０％以下（０を含む）、残部は実質的にＦｅの化学組成を有する体心立方晶の再結晶組織で成り、室温での引張試験による伸びが２０％以上、片持ち式固有振動法による振動減衰能Ｑ−１が５．０×１０−３以上の防振合金である。
好ましくは、飽和磁歪定数λｓが１０×１０−６以上、保磁力Ｈｃが２００Ａ／ｍ以下である上記の防振合金である。
That is, in the present invention, C: 0.10% or less (including 0), Si: 0.01 to 3.50%, Mn: 0.01 to 2.0%, Co: 5.0 to 26 by mass%. Less than 0.0%, Al: 3.50% or less (including 0), the balance is substantially composed of a recrystallized structure of a body-centered cubic crystal having a chemical composition of Fe, and an elongation by a tensile test at room temperature is 20% As described above, the vibration damping capacity Q −1 by the cantilever natural vibration method is 5.0 × 10 −3 or more.
Preferably, the vibration-proof alloy has a saturation magnetostriction constant λ s of 10 × 10 −6 or more and a coercive force Hc of 200 A / m or less.
本発明の防振合金は、高い振動減衰能と優れた冷間加工性を兼備するので、素材製造の行い易い実用的な防振合金である。 The anti-vibration alloy of the present invention is a practical anti-vibration alloy that is easy to manufacture materials because it has both high vibration damping ability and excellent cold workability.
上述したように、本発明の第一の特徴は、Ｆｅ−Ｃｏ系を基本組成とする防振合金の振動減衰能と冷間加工性を兼備させるべく、Ｃｏ量の調整を行った点にある。
また、磁壁移動の容易な軟磁性とするために、Ｃｏ以外の元素の含有量を調整した点にある。以下、本発明における化学組成の規定理由を述べる。なお以下に示す元素の含有量は質量％である。
Ｃ：０．１０％以下（０を含む）
Ｃは、炭化物となって磁壁移動を阻害し、軟磁性を劣化させる作用をもつ元素である。Ｃを０．１０％以下としたのは、Ｃが０．１０％を超えると、炭化物の生成による軟磁性の劣化が顕著となるからである。Ｃのより好ましい範囲は０．０５％以下であり、０％（無添加レベル以下）であることが最も望ましい。
As described above, the first feature of the present invention is that the amount of Co is adjusted in order to combine the vibration damping ability and cold workability of the vibration-proof alloy having a basic composition of Fe-Co. .
In addition, the content of elements other than Co is adjusted in order to make the domain wall easily soft magnetic. The reasons for defining the chemical composition in the present invention will be described below. In addition, content of the element shown below is the mass%.
C: 0.10% or less (including 0)
C is an element that acts as a carbide to inhibit domain wall movement and degrade soft magnetism. The reason why C is made 0.10% or less is that when C exceeds 0.10%, soft magnetic deterioration due to the formation of carbides becomes remarkable. A more preferable range of C is 0.05% or less, and most desirably 0% (below the additive-free level).
Ｓｉ：０．０１〜３．５０％
Ｓｉは、軟磁性の向上に有効な元素である。但し、０．０１％未満では軟磁性向上の効果が小さく、また３．５０％を超える範囲では優れた軟磁性が得られるものの、冷間加工性が著しく劣化するので０．０１〜３．５０％の範囲に規定した。Ｓｉのより好ましい範囲は０．１０〜３．０％である。
Ｍｎ：０．０１〜２．０％
Ｍｎは、脱酸元素として防振合金中の酸素量低減に有効な元素である。但し、０．０１％未満では効果が小さく、逆に２．０％を超える範囲では軟磁性を劣化させるので０．０１〜２．０％の範囲に規定した。Ｍｎのより好ましい範囲は、０．０５〜１．０％である。
Si: 0.01 to 3.50%
Si is an element effective for improving soft magnetism. However, if it is less than 0.01%, the effect of improving soft magnetism is small, and if it exceeds 3.50%, excellent soft magnetism is obtained, but the cold workability is remarkably deteriorated, so that 0.01 to 3.50. In the range of%. A more preferable range of Si is 0.10 to 3.0%.
Mn: 0.01 to 2.0%
Mn is an effective element for reducing the amount of oxygen in the vibration-proof alloy as a deoxidizing element. However, if the content is less than 0.01%, the effect is small. Conversely, if the content exceeds 2.0%, the soft magnetism is deteriorated. A more preferable range of Mn is 0.05 to 1.0%.
Ｃｏ：５．０〜２６．０％未満
Ｃｏは、本発明の防振合金の振動減衰能と冷間加工性に大きく影響する本発明の最重要元素である。Ｃｏ量の下限を５．０％としたのは、５．０％未満の範囲では飽和磁歪定数λｓ、ひいては振動減衰能Ｑ−１を高める効果が小さいからである。一方、Ｃｏ量の上限を２６．０％未満としたのは、２６．０％以上の範囲では規則相が出現し、冷間加工性を著しく劣化させるためである。これらの理由から、Ｃｏ量の範囲を５．０〜２６．０％未満に規定した。Ｃｏ量のより望ましい範囲は、８．０〜２５．０％である。
Co: 5.0 to less than 26.0% Co is the most important element of the present invention that greatly affects the vibration damping ability and cold workability of the vibration-proof alloy of the present invention. The reason why the lower limit of the amount of Co is set to 5.0% is that the effect of increasing the saturation magnetostriction constant λs and hence the vibration damping capacity Q −1 is small in the range of less than 5.0%. On the other hand, the reason why the upper limit of the amount of Co is set to less than 26.0% is that a regular phase appears in the range of 26.0% or more, and the cold workability is remarkably deteriorated. For these reasons, the range of Co content is specified to be 5.0-26.0%. A more desirable range of the amount of Co is 8.0 to 25.0%.
Ａｌ：３．５０％以下（０を含む）
Ａｌは、Ｓｉと同様に軟磁性の向上に有効な元素である。但し、防振合金中に硬質介在物であるＡｌ２Ｏ３を生成して冷間加工性を若干劣化させるので、０％（無添加レベル以下）でも良い。Ａｌを添加する場合の上限を３．５０％以下としたのは、３．５０％を超える範囲では冷間加工性が著しく劣化するからである。Ａｌのより好ましい範囲は３．０％以下（０％を含む）である。
残部は実質的にＦｅ
残部は実質的にＦｅとしたが、Ｐ、Ｓ、Ｎ、Ｏ等の不可避的不純物は含まれる。これらの元素は、振動減衰能と冷間加工性を劣化させない量として、それぞれ０．０５％以下含有しても良い。
Al: 3.50% or less (including 0)
Al, like Si, is an element effective for improving soft magnetism. However, since Al 2 O 3 which is a hard inclusion is generated in the vibration-proof alloy and the cold workability is slightly deteriorated, 0% (no additive level or less) may be used. The reason why the upper limit in the case of adding Al is set to 3.50% or less is that the cold workability is remarkably deteriorated in the range exceeding 3.50%. A more preferable range of Al is 3.0% or less (including 0%).
The balance is substantially Fe
The balance is substantially Fe, but unavoidable impurities such as P, S, N and O are included. These elements may be contained in amounts of 0.05% or less as amounts that do not deteriorate the vibration damping ability and the cold workability.
本発明の第二の特徴は、優れた振動減衰能と冷間加工性を得るために、防振合金の結晶構造と組織形態を調整した点にある。
防振合金の結晶構造を体心立方晶としたのは、防振合金を強磁性とするためである。また、防振合金の組織を再結晶組織としたのは、内部歪が解放された再結晶組織とすることによって軟磁性を向上させ、磁壁移動を容易にするためである。
The second feature of the present invention is that the crystal structure and structure of the vibration-proof alloy are adjusted in order to obtain excellent vibration damping ability and cold workability.
The reason why the crystal structure of the vibration-proof alloy is body-centered cubic is to make the vibration-proof alloy ferromagnetic. The reason why the structure of the vibration-proof alloy is the recrystallized structure is to improve the soft magnetism and facilitate the domain wall movement by using the recrystallized structure with the internal strain released.
次に、本発明における諸特性の規定理由を述べる。
室温での引張試験による伸びが２０％以上であることとしたのは、この特性が、素材製造時に、室温での冷間加工を行うのに適した特性であるからである。伸びが２０％未満であると、素材製造工程での冷間圧延時に、割れが生じ易く実用に適さない。それ故、室温での引張試験による伸びを２０％以上とした。好ましくは、３０％以上であると良い。
また、片持ち式固有振動法による振動減衰能Ｑ−１を５．０×１０−３以上としたのは、この範囲が、例えば自動車内のエンジンや各種モータ周辺の防振部材として、適した特性であるからである。振動減衰能が、この範囲内であれば、エンジンやモータから発生した振動や音を速やかに減衰させることができるので、結果として静かで乗り心地の良い自動車となり易い。好ましくは、振動減衰能Ｑ−１が８．０×１０−３以上であると良い。
Next, the reasons for defining various characteristics in the present invention will be described.
The reason why the elongation by the tensile test at room temperature is 20% or more is that this characteristic is suitable for cold working at room temperature when manufacturing the material. If the elongation is less than 20%, cracks are likely to occur during cold rolling in the raw material manufacturing process, which is not suitable for practical use. Therefore, the elongation by the tensile test at room temperature is set to 20% or more. Preferably, it is 30% or more.
In addition, the reason why the vibration damping ability Q −1 by the cantilever natural vibration method is 5.0 × 10 −3 or more is suitable for this range, for example, as an anti-vibration member around an engine in an automobile or various motors. This is because it is a characteristic. If the vibration damping ability is within this range, vibrations and sounds generated from the engine and motor can be quickly attenuated, and as a result, the automobile is likely to be quiet and comfortable to ride. Preferably, the vibration damping ability Q −1 is 8.0 × 10 −3 or more.
好ましい範囲として、飽和磁歪定数λｓを１０×１０−６以上としたのは、高い振動減衰能を得るために、望ましい磁歪特性であるからである。飽和磁歪定数λｓがこの範囲であれば、図１に示す磁気−機械ヒステリシス、すなわち振動減衰量を大きくすることができる。
また、保磁力Ｈｃを２００Ａ／ｍ以下としたのは、図１に示す磁壁の移動を速やかに行わせるために望ましい特性であるからである。保磁力Ｈｃがこの範囲であれば、磁壁の移動は速やかであり、ひいては高い振動減衰能が得られる。
The reason why the saturation magnetostriction constant λs is set to 10 × 10 −6 or more as a preferable range is that desirable magnetostriction characteristics are obtained in order to obtain high vibration damping capability. If the saturation magnetostriction constant λ s is within this range, the magneto-mechanical hysteresis, that is, the vibration attenuation amount shown in FIG. 1 can be increased.
The reason why the coercive force Hc is set to 200 A / m or less is that it is a desirable characteristic for promptly moving the domain wall shown in FIG. When the coercive force Hc is within this range, the domain wall moves quickly, and thus a high vibration damping capability is obtained.
本発明の防振合金の製造工程例としては、まず、所定組成の合金を溶解鋳造後、１０００℃以上の温度に加熱して熱間鍛造と熱間圧延を行い、板厚２．０〜６．０ｍｍの熱間圧延鋼板を得る。この熱間圧延鋼板を６５０〜１０００℃の温度範囲で焼鈍することが望ましい。
更に薄い板厚の防振合金が必要な場合には、冷間圧延を行って板厚を下げた後に６５０〜１０００℃の温度範囲で再度、焼鈍を行うと良い。本発明の防振合金では、脆弱な規則相は出現しないので、非特許文献３に記載される合金の様に冷間圧延前の熱処理（焼鈍）後に急冷を行う必要は無く、炉冷等の低コストな冷却作業で良い。
As an example of a manufacturing process of the vibration-proof alloy of the present invention, first, an alloy having a predetermined composition is melt cast, and then heated to a temperature of 1000 ° C. or higher to perform hot forging and hot rolling, and a thickness of 2.0 to 6 A hot-rolled steel sheet of 0.0 mm is obtained. It is desirable to anneal this hot-rolled steel sheet in a temperature range of 650 to 1000 ° C.
When a vibration-proof alloy having a thinner plate thickness is required, it is preferable to perform annealing again in a temperature range of 650 to 1000 ° C. after performing cold rolling to lower the plate thickness. Since the brittle ordered phase does not appear in the vibration-proof alloy of the present invention, it is not necessary to perform rapid cooling after the heat treatment (annealing) before cold rolling as in the alloy described in Non-Patent Document 3, such as furnace cooling. Low cost cooling work is sufficient.
熱間圧延または冷間圧延後に行う焼鈍の望ましい温度範囲を６５０〜１０００℃としたのは、防振合金の再結晶組織を得るためであり、ひいては高い振動減衰能を得るためである。６５０℃以上で焼鈍することによって、再結晶組織が得られ、振動減衰能は高まる。
但し、焼鈍温度が１０００℃を超えると、焼鈍中に面心立方組織となるために防振合金の軟磁性は劣化し、ひいては振動減衰能が低下する。それ故、望ましい焼鈍温度範囲を６５０〜１０００℃とするのが良く。更に望ましくは、７００〜９５０℃であると良い。
The reason why the desirable temperature range of annealing performed after hot rolling or cold rolling is set to 650 to 1000 ° C. is to obtain a recrystallized structure of the vibration-proof alloy, and thus to obtain high vibration damping ability. By annealing at 650 ° C. or higher, a recrystallized structure is obtained and the vibration damping ability is increased.
However, when the annealing temperature exceeds 1000 ° C., a face-centered cubic structure is formed during annealing, so that the soft magnetism of the vibration-proof alloy is deteriorated and the vibration damping ability is lowered. Therefore, the desirable annealing temperature range is preferably 650 to 1000 ° C. More desirably, it is 700-950 degreeC.
本発明の防振合金の用途例として、図２に示すような、積層したモータ回転子４の両端を挟み込むワッシャー５としての用途が考えられる。モータ回転子４には、通常、表面を絶縁塗装した電磁鋼板（純鉄または無方向性珪素鋼板）を打抜き、積層した構造体が使用されるが、この構造体を回転した時には、振動と音が発生する。モータ回転子４の両端部に本発明の防振合金で成るワッシャ−５を挟み込むことによって、回転時の振動や騒音は低減される。
このワッシャー５を製造する場合には、熱間圧延または冷間された本発明の防振合金を所定形状に打抜いた後、６５０〜１０００℃の温度範囲で焼鈍してワッシャー５とすれば良い。
但し、熱間圧延または冷間圧延のままでは硬く、打抜き加工が難しい場合には、打抜き加工を行う前に６５０〜１０００℃の温度範囲で焼鈍しても良い。打抜き加工を行うと、打抜き時のせん断歪の影響により、振動減衰能は打抜き前と比較して若干、劣化するので、その特性劣化が問題となる場合には、打抜き加工後のワッシャー５を再度、６５０〜１０００℃の温度範囲で焼鈍すると良い。
As an application example of the vibration-proof alloy of the present invention, a use as a washer 5 for sandwiching both ends of a laminated motor rotor 4 as shown in FIG. 2 can be considered. The motor rotor 4 is usually a structure obtained by punching and laminating electromagnetic steel sheets (pure iron or non-oriented silicon steel sheets) with insulating coating on the surface. When this structure is rotated, vibration and sound are generated. Will occur. By inserting the washer 5 made of the vibration-proof alloy of the present invention between both ends of the motor rotor 4, vibration and noise during rotation are reduced.
In the case of manufacturing the washer 5, after the hot-rolled or cold-damped alloy of the present invention is punched into a predetermined shape, the washer 5 may be annealed in a temperature range of 650 to 1000 ° C. .
However, if it is hard as hot rolling or cold rolling and punching is difficult, it may be annealed in a temperature range of 650 to 1000 ° C. before punching. When punching is performed, the vibration damping capability is slightly deteriorated due to the influence of shear strain at the time of punching, so that the deterioration of characteristics becomes a problem. It is good to anneal in the temperature range of 650-1000 degreeC.
以下の実施例で、本発明を更に詳しく説明する。
真空溶解炉を用いて、１０ｋｇの合金を５種類溶製した。各合金の化学組成を表１に示す。Ｎｏ．１、２は、本発明で規定した防振合金の化学組成に相当する。一方、Ｎｏ．３〜５は、比較例の防振合金の化学組成に相当する。
Ｎｏ．３では、Ｃｏが無添加であり、逆にＮｏ．４では、Ｃｏ含有量が４９．０５％と高い。Ｎｏ．４は、特許文献２に開示される防振合金に相当する。また、Ｎｏ．５は、１５．２０％のＣｒと３．０１％のＡｌを含有し、特許文献１に開示されるＦｅ−Ｃｒ−Ａｌ系を基本組成とした防振合金に相当する。
The following examples further illustrate the present invention.
Five types of 10 kg alloys were melted using a vacuum melting furnace. Table 1 shows the chemical composition of each alloy. No. 1 and 2 correspond to the chemical composition of the vibration-proof alloy defined in the present invention. On the other hand, no. 3 to 5 correspond to the chemical composition of the vibration-proof alloy of the comparative example.
No. In No. 3, Co was not added. In No. 4, the Co content is as high as 49.05%. No. 4 corresponds to the vibration-proof alloy disclosed in Patent Document 2. No. 5 corresponds to an anti-vibration alloy containing 15.20% Cr and 3.01% Al and having the basic composition of the Fe—Cr—Al system disclosed in Patent Document 1.
これら５種類の合金を１１００℃に加熱して熱間鍛造と熱間圧延を行い、厚さ５ｍｍの板材を得た。熱間加工時に生成した表面の酸化スケールを除去した後、アルゴン雰囲気炉中９２５℃で１時間保持の熱処理を行い、保持後に炉冷した。
熱処理を行った板材を冷間圧延したところ、Ｎｏ．１〜３とＮｏ．５は、冷間圧延できたが、Ｎｏ．４は、脆弱な規則相となるために割れが起こり、冷間圧延作業が不可能であった。
そこでＮｏ．４のみは、炉冷中に起こる規則化を抑制するため、９２５℃での１時間の保持後に４℃の食塩水中に急冷した板材を得た。この急冷した板材を冷間圧延したところ、割れることなく冷間圧延することができた。
These five kinds of alloys were heated to 1100 ° C. and subjected to hot forging and hot rolling to obtain a plate material having a thickness of 5 mm. After removing the oxide scale on the surface generated during hot working, heat treatment was performed for 1 hour at 925 ° C. in an argon atmosphere furnace, and the furnace was cooled after holding.
When the heat-treated plate was cold-rolled, no. 1 to 3 and no. No. 5 could be cold rolled, but no. Since No. 4 became a brittle regular phase, cracking occurred and cold rolling work was impossible.
No. Only No. 4 obtained a plate material that was quenched in 4 ° C. saline after holding at 925 ° C. for 1 hour in order to suppress the ordering that occurred during furnace cooling. When the rapidly cooled plate material was cold-rolled, it could be cold-rolled without cracking.
各材料の５ｍｍ厚の板材に対して圧下率７０％の冷間圧延を施し、厚さ１．５ｍｍの板材を得た。これらの板材より、エックス線回折測定、組織観察用の１．５ｍｍ×１０ｍｍ×１５ｍｍの試験片、ＪＩＳ１４Ｂ号相当の引張試験片、振動減衰能測定用の１．５ｍｍ×１０ｍｍ×６０ｍｍの短冊状試験片、磁歪測定用の１．５ｍｍ×１０ｍｍ×１２０ｍｍの板状試験片、磁性測定用の外径４５ｍｍ、内径３３ｍｍの環状試験片をそれぞれ切り出し、水素雰囲気炉中８５０℃で３時間の保持後、炉冷する熱処理を行った後に、種々の調査に供した。 Cold rolling with a rolling reduction of 70% was performed on a 5 mm thick plate of each material to obtain a 1.5 mm thick plate. From these plate materials, X-ray diffraction measurement, 1.5 mm × 10 mm × 15 mm test piece for structure observation, tensile test piece equivalent to JIS14B, 1.5 mm × 10 mm × 60 mm strip test piece for vibration damping capacity measurement A 1.5 mm × 10 mm × 120 mm plate test piece for magnetostriction measurement, an annular test piece with an outer diameter of 45 mm and an inner diameter of 33 mm for magnetism measurement were cut out and held at 850 ° C. for 3 hours in a hydrogen atmosphere furnace. After performing the cooling heat treatment, it was subjected to various investigations.
エックス線回折装置により、各合金の結晶構造を調べた。
例として、Ｎｏ．１、Ｎｏ．２、Ｎｏ．４のエックス線回折図形を図３に示す。いずれの合金にも体心立方晶の回折面（１１０）、（２００）、（２１１）面が検出されている。なお、Ｎｏ．３とＮｏ．５も、体心立方晶であった。
次に、組織観察用試験片を樹脂に埋め込み、鏡面研磨した後、Ｎｏ．１〜４は５％ナイタール溶液、Ｎｏ．５は塩化第二鉄溶液を用いて腐食を行い、光学顕微鏡を用いて組織観察を行った。観察例として、Ｎｏ．１の組織を図４に示す。
図４より、再結晶組織が得られていることが分かる。なお、Ｎｏ．２〜５の合金においても再結晶組織となっていた。
The crystal structure of each alloy was examined with an X-ray diffractometer.
As an example, no. 1, no. 2, no. The X-ray diffraction pattern of 4 is shown in FIG. In any alloy, the body-centered cubic diffraction planes (110), (200), (211) are detected. In addition, No. 3 and no. 5 was also a body-centered cubic crystal.
Next, the specimen for tissue observation was embedded in resin and mirror-polished, 1-4 are 5% nital solutions, No. No. 5 was corroded using a ferric chloride solution, and the structure was observed using an optical microscope. As an observation example, no. One organization is shown in FIG.
FIG. 4 shows that a recrystallized structure is obtained. In addition, No. The recrystallized structure was also found in the alloys 2-5.
次に、各種の試験片を用いて諸特性の測定を行った。
引張試験機を用いて室温で０．５ｍｍ／ｓの歪速度で引張試験を行い、破断までの伸びを測定した。磁歪測定用試験片に抗磁性ゲージを貼り付け、ソレノイドコイル内で１５０００Ａ／ｍの直流磁場を印加して飽和磁歪定数λｓを測定した。また、内部摩擦測定装置を用いて片持ち式固有振動法による振動減衰能Ｑ−１を測定した。
更に、環状試料に１次１５０回、２次３０回の巻線を施した後、直流磁束計により４００Ａ／ｍの磁場を印加してＢ−Ｈ特性を測定し、保磁力Ｈｃ（Ａ／ｍ）を測定した。これらの特性値を一覧にして表２に示す。
Next, various characteristics were measured using various test pieces.
Using a tensile tester, a tensile test was performed at room temperature at a strain rate of 0.5 mm / s, and the elongation to break was measured. An antimagnetic gauge was affixed to the test piece for magnetostriction measurement, and a saturation magnetostriction constant λs was measured by applying a DC magnetic field of 15000 A / m in the solenoid coil. Further, the vibration damping ability Q −1 by the cantilever natural vibration method was measured using an internal friction measuring device.
Further, after winding the primary specimen 150 times and secondary 30 times, the BH characteristic was measured by applying a magnetic field of 400 A / m with a DC magnetometer, and the coercive force H c (A / m) was measured. These characteristic values are listed in Table 2.
表２より、本発明のＮｏ．１〜２は、室温での引張試験による伸びが２０％以上、片持ち式固有振動法による振動減衰能Ｑ−１が５．０×１０−３以上の特性が得られるとともに、飽和磁歪定数λｓが１０×１０−６以上、保磁力Ｈｃが２００Ａ／ｍ以下の特性も満たしている。
これに対し、比較例のＮｏ．３とＮｏ．５では、Ｃｏが無添加であるために飽和磁歪定数λｓが低くなり、振動減衰能Ｑ−１が低い値となっている。逆に、比較例のＮｏ．４では、Ｃｏ量が４９．０５％と高いので、高い振動減衰能は得られているものの、規則相であるために６．２％の伸びしか得られていない。
From Table 2, the No. of the present invention. Nos. 1 and 2 are characterized in that the elongation at room temperature is 20% or more, the vibration damping ability Q −1 by the cantilever natural vibration method is 5.0 × 10 −3 or more, and the saturation magnetostriction constant λ. The characteristics that s is 10 × 10 −6 or more and the coercive force H c is 200 A / m or less are also satisfied.
In contrast, No. of the comparative example. 3 and no. In No. 5, since Co is not added, the saturation magnetostriction constant λ s is low, and the vibration damping ability Q −1 is low. On the contrary, No. of the comparative example. In No. 4, since the Co content is as high as 49.05%, a high vibration damping ability is obtained, but since it is a regular phase, only an elongation of 6.2% is obtained.
本発明では、防振合金の組織形態も重要である。振動減衰能Ｑ−１と保磁力Ｈｃに及ぼす焼鈍温度と組織の影響を調べるため、冷間圧延（圧下率７０％）を行った厚さ１．５ｍｍのＮｏ．１の板材より、各種の試験片を切り出し、真空炉内で５００〜９５０℃の各温度に１時間保持後、窒素ガスにより冷却した。振動減衰能Ｑ−１と保磁力Ｈｃに及ぼす冷間圧延後の焼鈍温度の影響を図５に示す。
図５より、冷間圧延後の焼鈍温度が高まるのに伴い、振動減衰能Ｑ−１は増加し、６５０℃以上の温度での焼鈍により、本発明の５．０×１０−３以上の振動減衰能が得られている。焼鈍温度を７００℃以上とすると、より望ましい特性である８．０×１０−３以上の振動減衰能となり、９００℃での焼鈍により、最も高い振動減衰能（１．３８×１０−２）が得られている。但し、焼鈍温度が９５０℃まで上昇すると、振動減衰能は若干、低下する。
図５より、本発明で望ましい特性とした８．０×１０−３以上の振動減衰能は、望ましい焼鈍温度範囲とした７００〜９５０℃の範囲で得られた。
一方、焼鈍温度が高くなるにつれ、保磁力Ｈｃは低下し、６５０℃以上の温度での焼鈍により、望ましい範囲とした２００（Ａ／ｍ）以下の保磁力となることが分かる。また、最も高い振動減衰能が得られた９００℃での焼鈍後には、最も低い保磁力（５１．２Ａ／ｍ）が得られている。
In the present invention, the structure of the vibration-proof alloy is also important. In order to investigate the influence of the annealing temperature and the structure on the vibration damping capacity Q- 1 and the coercive force Hc, a No. 1.5 mm thick steel sheet that was cold-rolled (rolling rate 70%) was used. Various test pieces were cut out from the plate material 1 and kept at 500 to 950 ° C. for 1 hour in a vacuum furnace, and then cooled with nitrogen gas. FIG. 5 shows the influence of the annealing temperature after cold rolling on the vibration damping capacity Q- 1 and the coercive force Hc.
From FIG. 5, as the annealing temperature after cold rolling increases, the vibration damping capacity Q −1 increases, and by annealing at a temperature of 650 ° C. or higher, the vibration of 5.0 × 10 −3 or higher of the present invention. Attenuation capacity is obtained. When the annealing temperature is 700 ° C. or higher, vibration damping ability of 8.0 × 10 −3 or more, which is a more desirable characteristic, is obtained, and the highest vibration damping ability (1.38 × 10 −2 ) is obtained by annealing at 900 ° C. Has been obtained. However, when the annealing temperature rises to 950 ° C., the vibration damping capacity slightly decreases.
From FIG. 5, the vibration damping ability of 8.0 × 10 −3 or more, which is a desirable characteristic in the present invention, was obtained in a range of 700 to 950 ° C. which is a desirable annealing temperature range.
On the other hand, as the annealing temperature increases, the coercive force Hc decreases, and it can be seen that annealing at a temperature of 650 ° C. or higher results in a coercive force of 200 (A / m) or less, which is a desirable range. Moreover, the lowest coercive force (51.2 A / m) is obtained after annealing at 900 ° C. in which the highest vibration damping capability is obtained.
更に、６５０℃で焼鈍した防振合金（本発明）と６００℃で焼鈍した防振合金（比較例）の組織を、それぞれ図６と図７に示す。６５０℃で焼鈍した防振合金の組織は再結晶しているのに対し、６００℃で焼鈍した防振合金には、冷間圧延の影響が残った未再結晶の組織となっている。
これらの実施例より、防振合金の化学組成と組織形態を本発明の規定範囲内とすることにより、目的とする冷間加工性と振動減衰能が得られることが分かる。
Furthermore, the structures of the vibration-proof alloy annealed at 650 ° C. (invention) and the vibration-proof alloy annealed at 600 ° C. (comparative example) are shown in FIGS. 6 and 7, respectively. While the structure of the vibration-proof alloy annealed at 650 ° C. is recrystallized, the vibration-proof alloy annealed at 600 ° C. has an unrecrystallized structure that remains affected by cold rolling.
From these examples, it can be seen that the desired cold workability and vibration damping ability can be obtained by setting the chemical composition and the structure of the vibration-proof alloy within the specified range of the present invention.
本発明の防振合金は、優れた冷間加工性と振動減衰能を兼備しているため、実用性に優れ、例えば自動車のエンジンやモータ周辺の防振部材として適用できる。 Since the vibration-proof alloy of the present invention has both excellent cold workability and vibration damping capability, it has excellent practicality and can be applied as, for example, a vibration-proof member around an automobile engine or motor.
１．機械的な歪、
２．磁歪、
３．磁気−機械ヒステリシス、
４．モータ回転子（電磁鋼板製）、
５．ワッシャー（防振合金製）
1. Mechanical distortion,
2. Magnetostriction,
3. Magneto-mechanical hysteresis,
4). Motor rotor (made of magnetic steel sheet),
5). Washer (made of vibration-proof alloy)
Claims (2)
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| JP2004036195A JP2005226126A (en) | 2004-02-13 | 2004-02-13 | Vibration-proofing alloy |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2004036195A JP2005226126A (en) | 2004-02-13 | 2004-02-13 | Vibration-proofing alloy |
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|---|---|
| JP2005226126A true JP2005226126A (en) | 2005-08-25 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007182853A (en) * | 2006-01-10 | 2007-07-19 | Hitachi Plant Technologies Ltd | Air compressor |
| WO2010041532A1 (en) | 2008-10-10 | 2010-04-15 | 株式会社豊田自動織機 | Iron alloy, iron alloy member and manufacturing method therefor |
| JP2017002395A (en) * | 2015-05-04 | 2017-01-05 | カーペンター テクノロジー コーポレーションＣａｒｐｅｎｔｅｒ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏｒｐｏｒａｔｉｏｎ | Ultra-low cobalt iron-cobalt magnetic alloys |
-
2004
- 2004-02-13 JP JP2004036195A patent/JP2005226126A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007182853A (en) * | 2006-01-10 | 2007-07-19 | Hitachi Plant Technologies Ltd | Air compressor |
| WO2010041532A1 (en) | 2008-10-10 | 2010-04-15 | 株式会社豊田自動織機 | Iron alloy, iron alloy member and manufacturing method therefor |
| US8641835B2 (en) | 2008-10-10 | 2014-02-04 | Kabushiki Kaisha Toyota Jidoshokki | Iron alloy, iron-alloy member, and process for manufacturing the same |
| JP2017002395A (en) * | 2015-05-04 | 2017-01-05 | カーペンター テクノロジー コーポレーションＣａｒｐｅｎｔｅｒ Ｔｅｃｈｎｏｌｏｇｙ Ｃｏｒｐｏｒａｔｉｏｎ | Ultra-low cobalt iron-cobalt magnetic alloys |
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