JP6839985B2 - Magnetic shield member, manufacturing method of magnetic shield member and magnetic shield panel - Google Patents

Description

The present invention relates to a magnetic shield member suitable for a biomagnetic measuring device.

As the soft magnetic material used for the magnetic shield, permalloy made of Fe—Ni based alloy, silicon steel plate (electromagnetic steel plate) made of Fe—Si alloy, electromagnetic soft iron and the like are well known. Generally, the magnetic shield property is proportional to the thickness of the soft magnetic material used, so if you want to obtain high magnetic shield property, you can increase the thickness of the soft magnetic material. For example, the wall surface of the magnetic shield room is magnetically shielded. In this case, a plate material made of Permalloy having a thickness of about 1 mm to several mm is required. If such a plate material is attached over the entire wall surface, the weight becomes considerable. Therefore, a lightweight magnetic shield member has been proposed while ensuring desired magnetic shield characteristics by using an amorphous magnetic material having high magnetic characteristics even if the thickness is thin (for example, Patent Document 1). .. Since the amorphous magnetic material is usually produced by ultra-quenching the molten metal on the surface of a roll that rotates at high speed, it is provided as a thin band having a thickness of about 10 to 30 μm.

There is a shield room of a biomagnetic measuring device as an application of a magnetic shield. Since the biomagnetic measuring device measures a weak magnetic field, this shield room is required to have high magnetic shielding characteristics. Therefore, even if an amorphous magnetic material is used, it is necessary to laminate a plurality of amorphous magnetic strips.

There is an adhesive as a means for laminating amorphous magnetic strips. For example, Patent Documents 2 and 3 propose to bond an amorphous magnetic strip via a heat-resistant thermoplastic resin. According to Patent Documents 2 and 3, Co-based amorphous is obtained by simultaneously performing laminating adhesion and annealing under specific conditions, or laminating adhesion under specific conditions and then annealing under specific conditions. A laminate having both the excellent magnetic properties and mechanical strength of the frustrated metal strip can be obtained.

Japanese Patent No. 5865143 Japanese Patent No. 4183463 Japanese Unexamined Patent Publication No. 2005-10409

In the bonded body formed by adhering the amorphous magnetic strips, the work of applying the adhesive to the amorphous magnetic strips becomes heavy as the number of layers increases.
The present invention has been made based on such a problem, and an object of the present invention is to provide a magnetic shield member which is easy to produce a laminated body and has excellent magnetic characteristics.

For this purpose, the magnetic shield member of the present invention is composed of a laminated body in which a plurality of magnetic layers and a plurality of non-magnetic metal bonding layers are alternately laminated, and the adjacent magnetic layer and the non-magnetic metal bonding layer are formed. It is characterized in that a part of the surface layer of the non-magnetic metal bonding layer is press-fitted into a recess formed on the surface of the magnetic layer as a protrusion.
According to the magnetic shield member of the present invention, a part of the surface layer of the non-magnetic metal bonding layer is press-fitted into a recess formed on the surface of the magnetic layer as a protrusion to bond the magnetic layer and the non-magnetic metal bonding layer. It is done by things. This bonding can be performed by alternately laminating a plurality of magnetic layers and a plurality of non-magnetic metal bonding layers and applying pressure in the stacking direction to cause the non-magnetic metal bonding layers to undergo plastic deformation. The work load of obtaining a joint is smaller than that of joining with.

In the magnetic shield member of the present invention, each magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm, and each non-magnetic metal bonding layer is an aluminum or aluminum alloy having a thickness of 10 to 30 μm. It is preferably composed of.
The Co-based amorphous metal is particularly suitable for the magnetic shield of a biomagnetic measuring device that measures a weak magnetic field. Further, since aluminum or an aluminum alloy has a small specific gravity, it contributes to weight reduction of the magnetic shield member.

The magnetic shield member of the present invention can be manufactured by the following method according to the present invention. This manufacturing method consists of a laminating step of alternately laminating a plurality of magnetic layers and a plurality of non-magnetic metal bonding layers to obtain a laminated body, and pressurizing the laminated body while heating to obtain each magnetic layer and each non-magnetic layer. It includes a joining step of joining magnetic metal bonding layers to obtain a bonded body and a heat treatment step of heat-treating the bonded body. The bonding step includes a bonding step in the range of 10 to 50 MPa at a temperature of 300 to 500 ° C. The heat treatment step is characterized in that pressure is applied in the longitudinal direction and the heat treatment step is maintained at a temperature of 300 to 500 ° C. for 0.1 to 100 hours in an inert gas atmosphere or atmosphere.
According to the manufacturing method of the present invention, each magnetic layer and each non-magnetic metal bonding layer can be bonded to obtain a bonded body by pressurizing the laminated body while heating, so that the bonded body is bonded with an adhesive. The work load of obtaining a joint is smaller than that of. Further, since the heat treatment step is performed in a state where the magnetic layer is formed into a laminated body together with the non-magnetic metal bonding layer, even if the magnetic layer becomes fragile due to the heat treatment, excessive care is not required for its handling. ..

In the present invention, typically, each magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm, and each non-magnetic metal bonding layer is made of aluminum or aluminum having a thickness of 10 to 30 μm. Made of alloy. Further, the thickness of the laminated body is typically 1 to 3 mm.

In the production method of the present invention, the joining step can also serve as a heat treatment step. In this case, the joining step is performed in an inert gas atmosphere or an atmosphere, and the time for applying pressure is 0.1 to 100 hours, or the total time for applying pressure and releasing pressure is 0. It may be 1 to 100 hours.

The present invention provides the following magnetic shield panel using the above-mentioned magnetic shield member. That is, the present invention includes a first shield group in which a plurality of first magnetic shield members having a predetermined length are arranged with a predetermined gap so that their first longitudinal directions are parallel to each other, and a predetermined length. The second shield group, the first shield group, and the second shield group are fixed, in which a plurality of second magnetic shield members having a sword are arranged with a predetermined gap so that their respective second longitudinal directions are parallel to each other. It is provided with a base material to be used.
In the magnetic shield panel of the present invention, the first shield group and the second shield group are laminated so that the first longitudinal direction of the first magnetic shield member intersects the second longitudinal direction of the second shield member, and the first magnetism The shield member and the second magnetic shield member are composed of a laminated body in which a plurality of magnetic layers and a plurality of non-magnetic metal bonding layers are alternately laminated, and the adjacent magnetic layer and the non-magnetic metal bonding layer are the surfaces of the magnetic layer. A part of the surface layer of the non-magnetic metal bonding layer is press-fitted into the recess formed in the above as a protrusion.

In the magnetic shield panel of the present invention, each magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm, and each non-magnetic metal bonding layer is made of aluminum or an aluminum alloy having a thickness of 10 to 30 μm. can do.

According to the present invention, it is possible to provide a magnetic shield member which is easy to produce a laminated body and has excellent magnetic characteristics.

(A) is a cross-sectional view showing a laminated structure of the magnetic shield member of this embodiment, (b) is a partially enlarged view of (a), and (c) is a plan view. It is a figure which shows the procedure of manufacturing the magnetic shield member of this embodiment. The state of joining the Co-based amorphous metal strip and the aluminum alloy strip in the present embodiment is schematically shown. (A) is before heating / pressurizing, and (b) is after heating / pressurizing. Shown. It is a table which shows the evaluation result of an Example and a comparative example. It is a table which shows the evaluation result of an Example and a comparative example. (A) is an image showing a cross section of the magnetic shield member according to the embodiment in the stacking direction by an optical microscope, and (b) is a partially enlarged image of (a). The magnetic shield panel according to this embodiment is shown, (a) shows only the first magnetic shield member, (b) shows only the second magnetic shield member, and (c) shows the first magnetic shield member and the second magnetic. A form in which shield members are combined is shown.

Hereinafter, the present invention will be described in detail based on the embodiments shown in the accompanying drawings.
As shown in FIG. 1, the magnetic shield member 10 in the present embodiment has a rectangular planar shape, and a plurality of amorphous magnetic layers 1 and a plurality of non-magnetic metal bonding layers 5 alternate in a cross section thereof. It has a structure laminated to. In the magnetic shield member 10, each amorphous magnetic layer 1 and each non-magnetic metal bonding layer 5 are bonded by an anchor effect. The magnetic shield member 10 has a thickness of about 1 to 3 mm as a laminated body.
Hereinafter, the configuration of the magnetic shield member 10 will be described in detail, and then a method for manufacturing the magnetic shield member 10 will be described.

[Amorphous magnetic layer 1]
The amorphous magnetic layer 1 constituting the magnetic shield member 10 is made of an amorphous metal strip and bears the effect of the magnetic shield in the magnetic shield member 10.
As the amorphous metal, a Co-based amorphous metal and an Fe-based amorphous metal can be used. As a normal soft magnetic member, a Co-based amorphous metal is used in applications that require high magnetic permeability, and an Fe-based amorphous metal having a high saturation magnetic flux density is used in applications that shield high-density magnetic flux. Be done. As the amorphous metal in the present embodiment, both a Co-based amorphous metal and an Fe-based amorphous metal can be used, but either one may be selected depending on the specific use of the magnetic shield. .. For example, since a biomagnetic measuring device is required to have a magnetic shield at a low magnetic field and a low frequency, it is preferable to use a Co-based amorphous metal having a high magnetic permeability at a low magnetic field and a low frequency.

As typical composition systems of Co-based amorphous metals, Co-Fe-Si-B system, Co-Si-B system, and Co-B system are known, and specifically, the following formula (1) is used. The chemical composition indicated by the atomic ratio can be adopted.
[Co _1-c · Fe _c ] _100-ab · X _a · Y _b ... Equation (1)
In equation (1), X, Y, a, b, and c are as follows.
X: At least one element selected from Si, B, C, P, Ge Y: Zr, Nb, Ti, Hf, Ta, W, Cr, Mo, V, Ni, Al, Pt, Rh, Ru, At least one or more elements selected from Sn, Sb, Cu, Mn or rare earth elements a: 10 <a≤35
b: 0 ≦ b ≦ 30
c: 0 ≦ c ≦ 0.3

Element X is an element effective for reducing the crystallization rate due to amorphization in the production of an amorphous metal strip. If a is less than 10, amorphization may decrease and some crystalline material may be mixed, and if a exceeds 35, an amorphous structure can be obtained, but the mechanical strength of the alloy strip is obtained. May decrease and continuous thin bands may not be obtained. Therefore, in this embodiment, 10 <a ≦ 35 is preferable, and 12 ≦ a ≦ 30 is more preferable.
Element Y has the effect of facilitating heat treatment to bring out soft magnetism by lowering the Curie temperature of the amorphous metal strip, and in particular, Zr, Nb, W, Mo, Cr, V, Ni, Al, Pt, Rh. , Ru, Mn, are effective. If b exceeds 30, the amorphous metal strip may become fragile. Therefore, in this embodiment, 0 ≦ b ≦ 30 is preferable, and 0 ≦ b ≦ 20 is more preferable.
In the amorphous metal strip, the saturation magnetization can be increased by substituting a part of Co with Fe. Further, by adjusting the atomic ratio of Co: Fe, the magnetostrictive constant is reduced and the soft magnetism is further enhanced. It is known that typically Co: Fe = 94: 6 and the saturated magnetostrictive constant becomes zero. Therefore, in this embodiment, 0 ≦ c ≦ 0.3 and 0 ≦ c ≦ 0.25 are more preferable.

Typical Fe-based amorphous metals include Fe-semi-metal-based amorphous metal materials such as Fe-B-Si-based, Fe-B-based, and Fe-PC-based materials, and Fe-Zr. Fe-transition metal-based amorphous metal materials such as systems, Fe-Hf-based, and Fe-Ti-based materials are known, and any composition system can be used in the present embodiment. 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%) and the like can be mentioned.

In the present invention, Fe-based nanocrystalline magnetic metal can be used in addition to the amorphous metal. Since this nanocrystalline magnetic metal is amorphous before the heat treatment for forming nanocrystals, it is an Fe-based amorphous metal in the laminated state before the heat treatment.
The nanocrystalline magnetic metal has a composition represented by the following general formula, and at least 50% of the structure is composed of fine crystal grains having an α-Fe-based bcc structure having an average particle size of 1000 Å or less. For the rest, a substantially amorphous phase in which Cu-based clusters are dispersed can be applied.
General _{formula: (Fe 1-a M a} ) 100 -x-y-z-α Cu x Si y B z M 'α
However, M, M', a, x, y, z and α are as follows.
M: Co and / or Ni
M': At least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti and Mo a: 0≤a≤0.5
x: 0.1 ≦ x ≦ 3
y: 0 ≦ y ≦ 30
z: 0 ≦ z ≦ 25,
y + z: 5 ≦ y + z ≦ 30
α: 0.1 ≤ α ≤

The above nanocrystalline magnetic metal can contain the following elements.
M ": At least one element selected from the group consisting of V, Cr, Mn, Al, white metal element, Sc, Y, rare earth element, Au, Zn, Sn, Re X: C, Ge, P, Ga , Sb, In, Be, As at least one element selected from the group

The amorphous metal strip used in the present invention is produced by ultra-quenching molten metal adjusted to a predetermined composition on the surface of a roll rotating at high speed, and has a thickness of 5 to 50 μm. It has a thickness of preferably 10 to 30 μm. Further, this amorphous metal strip has a width of 12.7 to 213.4 mm (0.5 to 8.4 inches). In addition, the length of this amorphous metal strip can be made extremely long due to the manufacturing method.

The amorphous metal strip obtained by the molten metal quenching method exhibits excellent soft magnetic properties when subjected to heat treatment. The conditions of the heat treatment vary depending on the magnetic properties to be expressed and the type of amorphous metal, but are generally carried out in an inert atmosphere at a temperature of about 300 to 500 ° C. and a time of 0.1 to 100 hours. Although excellent magnetic properties are exhibited by undergoing this heat treatment, the amorphous metal structure changes, resulting in an extremely fragile thin band. Therefore, in the present embodiment, the amorphous metal strip is not heat-treated by itself, but is heat-treated as a bonded body with the non-magnetic metal bonding layer 5.

[Non-magnetic metal bonding layer 5]
Next, the non-magnetic metal bonding layer 5 plays a role of bonding the amorphous magnetic layer 1 in contact with the front surface and the back surface by the anchor effect. This bonding will be described later, but it is premised that the metal strips constituting the non-magnetic metal bonding layer 5 are plastically deformed.
The non-magnetic metal bonding layer 5 is preferably composed of a thin band made of light metal, which contributes to weight reduction of the magnetic shield member 10. As the light metal, aluminum or aluminum alloy or magnesium or magnesium alloy can be used, but aluminum or aluminum alloy is preferably used from the viewpoint of easy availability of a thin band and price. Since the specific gravity of aluminum (Al), magnesium (Mg), iron (Fe) and cobalt (Co) is 2.7, 1.7, 7.9 and 8.9, aluminum or magnesium is not used. The magnetic metal bonding layer 5 has a smaller specific gravity than the amorphous magnetic layer 1 using a Co-based amorphous metal or an Fe-based amorphous metal.

Since the non-magnetic metal bonding layer 5 joins the amorphous magnetic layer 1 by plastic deformation, aluminum or an aluminum alloy having high plastic deformation ability (hereinafter, collectively referred to as an aluminum alloy) is also from this point. It is a preferable material for this embodiment. The Co-based amorphous metal and Fe-based amorphous metal to which the joint is attached have low plastic deformability.

The non-magnetic metal bonding layer 5 is made of a non-magnetic metal such as an aluminum alloy, and exhibits a magnetic shielding effect against a time-varying magnetic field. This is because the magnetic field is shielded by the eddy current flowing through the non-magnetic metal bonding layer 5 which is a conductor so as to resist the fluctuation of the magnetic field perpendicularly interlinking with the non-magnetic metal bonding layer 5. The effect is high even in the high frequency band, and it can be said that it also has a radio wave shielding effect in this respect. Therefore, the magnetic shield member 10 in which the amorphous magnetic layer 1 and the non-magnetic metal bonding layer 5 are laminated has a magnetic shield effect on a magnetic field parallel to the surface and a fluctuating magnetic field vertically incident on the surface. On the other hand, the magnetic shield effect is reinforced, and the effect of the radio wave shield is superimposed.

As aluminum alloys, JIS 1000 series alloys (pure aluminum series), 2000 series (Al-Cu series), 3000 series (Al-Mn series), 4000 series (Al-Si series), 5000 series (Al-Mg series) ), 6000 series (Al-Mg-Si series), 7000 series (Al-Zn-Mg series) and the like. Any aluminum alloy can be applied to this embodiment, but it is preferable to use a 1000 series or 3000 series aluminum alloy having a large elongation, that is, a high plastic deformability.

The light metal strips constituting the non-magnetic metal bonding layer 5 are usually manufactured through casting, hot rolling, cold rolling and heat treatment, and the strips have a thickness of 5 to 100 μm. The metal strip in the present embodiment may be appropriately selected from this thickness range, but if it is too thin, plastic deformation may be insufficient, and if it is too thick, the amorphous magnetic layer 1 in the magnetic shield member 10 may be insufficient. Since the ratio is small, the thickness is preferably 10 to 40 μm, more preferably 10 to 30 μm.
Further, in the case of Al, this non-magnetic metal strip has a width of 50 to 1030 mm, preferably a width of 50 to 150 mm.

[Manufacturing method of magnetic shield member 10]
Next, a method of manufacturing the magnetic shield member 10 will be described.
It is assumed that the Co-based amorphous metal strip 2 is used as the amorphous magnetic layer 1 and the aluminum alloy strip 6 is used as the non-magnetic metal bonding layer 5, and the Co-based amorphous metal strip 2 having a predetermined size is used. And it is assumed that an aluminum alloy strip 6 having a predetermined size is prepared. The prepared Co-based amorphous metal strip 2 has not been heat-treated.
As shown in FIG. 2, the method for manufacturing the magnetic shield member 10 includes a laminating step, a joining step, and a heat treatment step. The heat treatment step can also be combined with the joining step.

[Laminating process]
In the laminating step, a plurality of Co-based amorphous metal strips 2 and a plurality of aluminum alloy strips 6 prepared in advance are alternately laminated. At the time of this lamination, the positions in the width direction and the length direction are aligned.
Prior to the laminating step, the surface of the Co-based amorphous metal strip 2 and the surface of the aluminum alloy strip 6 can be degreased and washed.

[Joining process]
If the laminate 8 composed of the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 is obtained, as shown in FIG. 2, the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 are formed. Move to the joining process for joining. In the joining step, pressurization P and heating H are applied to the laminate 8 at the same time.
This joining step is intended to cause plastic deformation in the vicinity of the surface of the aluminum alloy strip 6 and fill the minute dents existing on the surface of the Co-based amorphous metal strip 2.

As described above, the Co-based amorphous metal strip 2 is produced by ejecting molten metal onto the surface of a cooling roll that rotates at high speed, and is produced by this quenching solidification method as described below. A dent is formed on the front surface and the back surface of the Co-based amorphous metal strip 2.
Since the surface of the cooling roll is mirror-polished, the surface roughness of the thin band surface (roll contact surface) in contact with the surface of the cooling roll is relatively small and smooth, whereas the surface roughness of the contact surface is relatively small. Since the surface on the back side (roll non-contact surface) has no element that restricts the flow of molten metal, the surface roughness is large and relatively large irregularities are present. The roll contact surface has surface irregularities with a surface roughness of several μm or less, typically an average surface roughness of 2 μm or less, and the roll non-contact surface has a slightly larger undulating flow of the material surface. There is (large surface unevenness). That is, an air pocket is formed on the roll contact surface of the produced Co-based amorphous metal strip 2. This is because the accompanying gas generated by the rotation of the cooling roll expands inside the paddle before it solidifies when it is caught in the boundary layer between the hot water pool called the paddle and the cooling roll. Has been done. Further, the wavy unevenness of the roll non-contact surface reflects the unevenness of the roll contact surface and is also related to the vibration of the paddle.

In the present embodiment, the bonding with the aluminum alloy strip 6 is realized by utilizing the dents and irregularities existing on the roll contact surface and the roll non-contact surface of the Co-based amorphous metal strip 2. Hereinafter, this joining will be described with reference to FIG.
As shown in FIG. 3A, in the laminate 8 of the Co-based amorphous metal strip 2 and the aluminum alloy strip 6, the roll contact surface 2A and the roll non-contact of the Co-based amorphous metal strip 2 are not contacted. A recess 3 exists as a void on the surface 2B.
The laminate 8 is heated and pressure is applied from the front and back surfaces thereof to cause plastic deformation in the vicinity of the surface of the aluminum alloy strip 6. Then, since the Co-based amorphous metal strip 2 has a low plastic deformability, the recess 3 of the Co-based amorphous metal strip 2 maintains its morphology, while the surface layer of the aluminum alloy in which the plastic deformation occurs is the surface layer. It becomes a protrusion 7 and is press-fitted into the recess 3. In this way, as shown in FIG. 3B, the Co-based amorphous metal strip 2 and the aluminum alloy thin due to the anchor effect generated by press-fitting the protrusion 7 into the recess 3 of the contact surface 2A and the non-contact surface 2B. By joining the bands 6, a magnetic shield member 10 in which the amorphous magnetic layer 1 and the non-magnetic metal bonding layer 5 adjacent to each other in the thickness direction are bonded is obtained.

When the bonding interface between the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 in the magnetic shield member 10 according to the embodiment described later was confirmed, it was found that between the Co-based amorphous metal strip 2 and the aluminum alloy strip 6. The diffusion layer of the element of was not observed. Therefore, the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 can fulfill their respective functions.

In the joining step, conditions may be adopted that can achieve the purpose of causing plastic deformation of the aluminum alloy strip 6 and press-fitting it into the recess of the Co-based amorphous metal strip 2, and the pressure for pressurizing the laminate 8 and the pressure There are two factors of heating temperature.
In the case of the laminate 8 composed of the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 having the above-mentioned dimensions, a pressure of 0.1 to 50 MPa may be applied. The heating of the laminate 8 is performed to facilitate plastic deformation, and may be selected from the range of 300 to 500 ° C. If the heating temperature of the laminate 8 is raised, the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 can be joined even if the pressure is relatively lowered. The preferred pressure is 1 to 40 MPa, and the more preferred pressure is 3 to 35 MPa.

An apparatus that performs a joining process involving pressurization and heating is arbitrary, but an apparatus capable of simultaneously applying pressurization and heating, such as a hot press or an autoclave, can be widely applied.

[Heat treatment process]
The heat treatment is performed in order to exhibit the desired magnetic properties of the Co-based amorphous metal strip 2, and has already been applied to the laminate 8 composed of the Co-based amorphous metal strip 2 and the aluminum alloy strip 6. Will be done.
The conditions of this heat treatment vary depending on the magnetic properties to be expressed and the type of amorphous metal, but are appropriately selected from the range of a temperature of 300 to 500 ° C. and a holding time of 0.1 to 100 hours in an inert atmosphere. To.
The Co-based amorphous metal strip 2 becomes extremely fragile and difficult to handle after undergoing this heat treatment. However, in the present embodiment, the Co-based amorphous metal strip 2 and the aluminum alloy strip 6 are laminated, and the aluminum alloy strip 6 supports the Co-based amorphous metal strip 2, so that Co. It is possible to overcome the weakness of the single amorphous metal strip 2.

Since the above-mentioned joining step also involves heating, the joining step and the heat treatment step can be combined.
In this case, the atmosphere of the joining step is set to an inert gas atmosphere, and the pressurization and heating for joining are performed for a time corresponding to the time required for the heat treatment step.
Alternatively, the atmosphere of the joining process is set to an inert gas atmosphere, and the pressurization for joining is performed only in a specific time region of the time corresponding to the time required for the heat treatment step, and then the pressure application is released. You may. Pressurization may be performed at the initial stage, the middle stage, or the final stage.

As described above, the joining step and the heat treatment step can be combined, but as is clear from the examples described later, it is preferable to perform the joining step and the heat treatment step separately.

[Example]
Hereinafter, the present invention will be described with reference to Examples and Comparative Examples.
The Co-based amorphous metal strip and aluminum foil shown below were prepared and laminated alternately to prepare an evaluation sample, and the magnetic properties and the like were evaluated. The evaluation method and the method for preparing the evaluation sample are described below. The heat treatment conditions performed on the evaluation sample are also described below.

[Material used]
Co-based amorphous metal strip:
VITROVAC6025A Width: 50mm Plate thickness: 0.023mm (23μm)
Cordova queue Muş Merz Inc. (Curie temperature _T C = 200 ℃, the crystallization temperature Tx = 530 ° C.)
Aluminum foil: Product name N905 Width: 300 mm Plate thickness: 0.020 mm (20 μm)
Made by Toyo Aluminum Echo Products Co., Ltd.

[Evaluation methods]
Inductance Permeability: Measured by an impedance analyzer (HIOKI 3522-50 LCR HiTESTER) under the conditions of frequencies 5, 60 and 300 Hz.
DC initial magnetic permeability, maximum magnetic permeability: Measured with a BH analyzer (RIKEN DENSHI BHS-40). The measured magnetic field of the initial magnetic permeability is 0.4 A / m.
Tensile strength: Measured according to Japanese Industrial Standard JIS-K7127.
Young's modulus: According to Japanese Industrial Standard JIS-Z2280, Young's modulus at room temperature was measured in a free resonance mode by a resonance method.

[Evaluation sample preparation method]
[Ring sample for measuring magnetic properties]
Amorphous metal strip and aluminum foil were punched into a ring shape with an outer diameter of 45 mm and an inner diameter of 33 mm.
Twenty ring-shaped amorphous metal strips and 19 aluminum foils were alternately stacked, and the inner diameter side end of the laminated ring was temporarily fixed with office glue, and this sample was subjected to a heat press machine (Co., Ltd.). IMC-187C manufactured by Imoto Seisakusho) was used to form a laminate in the air under the conditions of pressure (0.1 to 37) MPa, temperature (350 to 500) ° C., and holding time of 30 minutes.

[Sample for tensile test]
A test piece of JIS-K7127 was punched out from the amorphous metal strip and the aluminum foil for a tensile test, and 40 punched amorphous metal strips and 39 aluminum foils were alternately stacked. Temporarily fix one end of the laminated sample on the grip side with office glue, and use a heat press machine (IMC-187C manufactured by Imoto Seisakusho Co., Ltd.) to temporarily fix the sample at pressure (0.1 to 37) MPa and temperature. A laminate was formed by molding in the air under the conditions of (350 to 500) ° C. and a holding time of 30 minutes.

[Sample for Young's modulus measurement]
A rectangular piece having a width of 10 mm and a length of 60 mm was punched from an amorphous metal strip and an aluminum foil according to JIS-Z2280 for measuring Young's modulus. The length of 60 mm was adjusted to the longitudinal direction of the amorphous metal strip. 40 rectangular amorphous metal strips and 39 aluminum foils were alternately stacked, and one end of the laminated sample was temporarily fixed with office glue, and a heat press machine (IMC- manufactured by Imoto Seisakusho Co., Ltd.) Using 187C), the laminate was formed in the air under the conditions of pressure (0.1 to 37) MPa, temperature (350 to 500) ° C., and holding time of 30 minutes.

[Heat treatment]
A part of the laminated body after molding was evaluated as it was, but in order to bring out the soft magnetic properties of the amorphous metal strip, it was not pressurized, the temperature was 450 ° C., the holding time was 30 minutes, and the nitrogen atmosphere was used. Heat treatment was performed inside.

[Comparative Example 1]
As a PC permalloy that is often used for magnetic shields, the following plate with a thickness of 1 mm was selected and evaluated. A ring-shaped sample having an outer diameter of 45 mm and an inner diameter of 33 mm was punched for magnetic measurement, and a test piece of JIS-K7127 was punched for a tensile test, and these were heat-treated in a hydrogen stream at 1100 ° C. and a holding time of 120 minutes. It was used for evaluation.
The evaluation result is shown in FIG. The same applies to the following comparative examples and examples.
PC Permalloy: ThyssenKrupp VDM Magnifer 7904

[Comparative Example 2]
The above-mentioned cobalt-based amorphous metal strip is punched into a ring shape with an outer diameter of 45 mm and an inner diameter of 33 mm, and 40 sheets are stacked on a measuring case for magnetic measurement and a JIS-K7127 test piece for a tensile test. Was punched out and subjected to a tensile test. Each was used for evaluation without heat treatment.
As a result, the initial magnetic permeability was 4,800, the maximum magnetic permeability was 224,200, and the tensile strength was 970 MPa. Compared with Comparative Example 1 of PC Permalloy, the initial magnetic permeability, which is the most important index in magnetic shielding applications, is remarkably low, and the gap with PC Permalloy 169,700 is large. The maximum magnetic permeability was about 2/3 of that of PC Permalloy. On the other hand, the tensile strength is as high as 970 MPa, which indicates the high strength of the amorphous metal strip that has not been heat-treated.

[Comparative Example 3]
The same amorphous metal strip as in Comparative Example 2 was punched out in the same manner as in Comparative Example 2 to prepare a test piece. These test pieces were heat-treated in a nitrogen atmosphere at a temperature of 350 ° C. and a holding time of 30 minutes without pressurization. Forty heat-treated ring-shaped test pieces were placed on a measuring case and subjected to magnetic measurement. In addition, the heat-treated tensile test piece was fragile and could not be chucked, so that the tensile test could not be performed.
As a result, the initial magnetic permeability was 142,000 and the maximum magnetic permeability was 303,100. The initial magnetic permeability was slightly inferior to that of PC Permalloy, but the maximum magnetic permeability was the same.

[Comparative Example 4]
The same amorphous metal strip as in Comparative Example 2 was punched out in the same manner as in Comparative Example 2 to prepare a test piece. These test pieces were heat-treated in a nitrogen atmosphere at a temperature of 450 ° C. and a holding time of 30 minutes without pressurization. Although magnetic measurement was possible, the sample after heat treatment was more brittle than Comparative Example 3, and a tensile test could not be performed.
As a result of magnetic measurement, the initial magnetic permeability was as high as 326,400 and the maximum magnetic permeability was 463,400, and the inductance magnetic permeability exceeded that of PC Permalloy (Comparative Example 1) at each frequency. These indicate that the material properties of the amorphous metal strip tend to be superior to those of PC permalloy.

[Examples 1 to 6]
A test piece was punched out from the above-mentioned cobalt-based amorphous metal strip in the same manner as in Comparative Example 2. At the same time, a test piece was prepared by punching the above-mentioned aluminum alloy foil in the same shape as the cobalt-based amorphous metal strip.
Temporarily fix the end of the magnetic measurement ring made of the laminate produced by the above method using these test pieces on the inner diameter side, and one end of the chucking part of the tensile test piece with a small amount of office glue. Then, using the above-mentioned hot press machine, molding in the atmosphere (350 ° C. × {0.1, 1, 3, 9, 29, 37} MPa) was performed to obtain a laminated body.
These laminates were subjected to evaluation without heat treatment.

As a result, as the molding pressure increased, the density of the molded body tended to increase and became denser, and the initial magnetic permeability, the maximum magnetic permeability, and the tensile strength tended to increase. In addition, the inductance magnetic permeability at 5 Hz in Example 6 was 59,100, which was comparable to that of PC Permalloy 55,800.

[Examples 7 to 9]
The material prepared in advance in the same manner as in Examples 1 to 6 was molded in the air (350 ° C. × {0.1, 1, 3} MPa) by a hot press to form a laminate, and the above heat treatment was performed.
As a result, among these three examples, the initial magnetic permeability of Example 9 having the highest molding pressure of 3 MPa was the highest, the initial magnetic permeability was 124,100, the maximum magnetic permeability was 268,100, and the tensile strength was 44 MPa. Obtained. Further, as can be seen by comparing with Examples 1 to 6, the magnetic properties are improved by performing the heat treatment.

[Examples 10 to 11]
A laminate sample molded in the air (350 ° C. × {9, 29} MPa) by a hot press in the same manner as in Examples 7 to 9 was similarly heat-treated and then evaluated.
As a result, in Example 10, the initial magnetic permeability was 285,800, the maximum magnetic permeability was 422,300, and the tensile strength was 76 MPa, and in Example 11, the initial magnetic permeability was 340,000, the maximum magnetic permeability was 516,100, and the tensile strength was 100 MPa. It was. The initial magnetic permeability, maximum magnetic permeability, and inductance magnetic permeability are all equal to or higher than those of PC Permalloy. Tensile strength was obtained at a certain level that could withstand use.

[Examples 12 to 16]
It was molded in the air by a hot press in the same manner as in Examples 10 to 11. The condition is 450 ° C. × {0.1, 1, 3, 9, 29} MPa).
The obtained laminate sample was subjected to evaluation without heat treatment.
As a result, in all cases, the initial magnetic permeability, the maximum magnetic permeability, and the inductance magnetic permeability were equal to or higher than those of PC Permalloy. The tensile strength shows a certain level that can withstand use.

[Examples 17 to 19]
It was molded in the air by a hot press in the same manner as in Examples 10 to 11. The condition is 450 ° C. × {3, 9, 29} MPa).
The obtained laminate sample was subjected to the above heat treatment and then evaluated.
As a result, in all of Examples 17 to 19, the initial magnetic permeability, the maximum magnetic permeability, and the inductance magnetic permeability were all equal to or higher than those of PC Permalloy. Compared with Examples 12 to 16, the magnetic properties were further improved by adding the heat treatment. The tensile strength shows a certain level that can withstand use.

[Examples 20 to 22]
It was molded in the air by a hot press in the same manner as in Examples 10 to 11. The conditions are (500 ° C. × {0.1, 1, 3} MPa). The obtained laminate sample was evaluated without heat treatment.

From Examples 1 to 22 above, it was clarified that by optimizing the conditions such as temperature and pressure, a laminate having excellent magnetic properties of the cobalt-based amorphous metal strip and the aluminum foil can be obtained.
When constructing a magnetic shield, typically a magnetic shield chamber, the soft magnetic material is used by reinforcing the strength with a structural material such as an aluminum frame, so the tensile strength as the material strength is in a secondary position. .. However, it is desirable to have sufficient reliability when assembling as a structure. Therefore, Young's modulus was measured with the actual thickness, and the flexural rigidity, which is an index of the flexibility of the wall surface as a structure, was calculated and estimated. The results are shown below together with a comparative example.
The flexural rigidity is a typical strength of materials index that depends on the thickness, not the material properties. The flexural rigidity D is represented by the following equation (1) as Young's modulus E, thickness t, and Poisson's ratio ν.
^{D = Et 3/12 (1} -ν 2) ... (1)

[Comparative Example 5]
A rectangular piece having a width of 10 mm and a length of 60 mm was punched out from a plate of PC permalloy having a thickness of 1 mm of Comparative Example 1. This was heat-treated in a hydrogen stream at 1100 ° C. for 60 minutes, and Young's modulus was measured by a resonance method. The results are shown in FIG. The same applies to the following examples.
The measured Young's modulus was 170 GPa. This test piece has a plate thickness of 0.99 mm, and the flexural rigidity D is 15.6 Pa · m ^{3 when} calculated from the known Poisson's ratio of 0.3.

[Example 23]
A laminate having a width of 10 mm, a length of 60 mm, and a thickness of 0.85 mm was produced in the same manner as in Example 10. The obtained laminate sample was subjected to the same heat treatment as in Example 10, and the Young's modulus was evaluated in the same manner as in Comparative Example 5.
Young's modulus was 25 GPa. Based on this result, the flexural rigidity D was determined in the same manner as in Comparative Example 5. The Poisson's ratio was 0.3. In the calculation, the total thickness of the laminated sample was 1.87 mm, but the thickness of only the amorphous metal strip, that is, the thickness of the magnetic material was the same as that of PC Permalloy in Comparative Example 5. It becomes 01 mm.
As a result, the flexural rigidity D was 15.0 Pa · m ³ . This value is substantially equal to the bending rigidity of the PC permalloy having a thickness of 0.99 mm in Comparative Example 5.

[Example 24]
A laminate having a width of 10 mm, a length of 60 mm, and a thickness of 0.84 mm was produced in the same manner as in Example 15. The obtained laminate sample was subjected to the same heat treatment as in Example 15, and the Young's modulus was evaluated in the same manner as in Comparative Example 5.
Young's modulus was 27 GPa. Based on this result, the flexural rigidity D was determined in the same manner as in Example 23. The Poisson's ratio was 0.3. In the calculation, the total thickness of the laminated sample was 1.87 mm, but only the amorphous metal strip, that is, the thickness as a magnetic material was 1.01 mm, which is equivalent to the PC permalloy of Comparative Example 5. Become. As a result, the flexural rigidity D was 16.2 Pa · m ³ . This value slightly exceeds the bending rigidity of the PC permalloy having a thickness of 0.99 mm in Comparative Example 5.

The laminated sample of Examples 23 and 24 corresponds to Examples 10 and 15, respectively. The tensile strengths of Examples 10 and 15 are 76 MPa and 84 MPa, which are different from the 135 MPa of PC Permalloy of Comparative Example 1, but the thickness of the laminated body laminated with the aluminum foil is the same as that of the magnetic material. If it is 1.87 mm, it has a bending rigidity equivalent to that of PC permalloy, and suggests that a highly reliable shield can be constructed.
It is understood that the distant cause of this phenomenon is that the Young's modulus of aluminum is 70 GPa, which is relatively high as a soft material. Incidentally, it is difficult to actually measure Young's modulus with an amorphous metal strip, but the literature value is at the level of 100 GPa.

Next, FIG. 6 shows a cross section of the magnetic shield member 10 according to the embodiment in the stacking direction.
As shown in FIG. 6, the protrusion 7 of the aluminum alloy thin band 6 in which the recess 3 of the Co-based amorphous metal strip 2 is plastically deformed is press-fitted into the recess 3, so that an anchor effect is generated and the Co-based non-co-based band 6 is not formed. It was confirmed that the crystalline metal strip 2 and the aluminum alloy strip 6 were joined.

[Magnetic shield panel]
Next, the magnetic shield member 10 according to the present embodiment contains an amorphous metal as an element, but since the amorphous metal is caused by a manufacturing process called a quenching solidification method, the dimensions in the width direction are restricted. Therefore, when it is necessary to magnetically shield a region having a large area, it is desirable to arrange a plurality of magnetic shield members 10 on a plane to form a panel. Therefore, an example of a preferable magnetic shield panel 20 using the magnetic shield member 10 will be described. The magnetic shield panel 20 is used to prevent the influence of an external magnetic field from affecting the inside of the magnetic shield device by installing it on the inner wall or the outer wall of the magnetic shield device such as the magnetic shield room or the magnetic shield chamber. Further, the magnetic shield panel 20 is used to prevent the influence of the magnetic field generation source installed inside the magnetic shield device from affecting the outside.

As shown in FIG. 7C, the magnetic shield panel 20 of the present embodiment is a group to which the first shield group 11, the second shield group 12, the first shield group 11 and the second shield group 12 are fixed. The material 15 and the material 15 are provided.
The first shield group 11 is configured by arranging a plurality of strip-shaped first magnetic shield members 10A at predetermined intervals so that their first longitudinal directions are parallel to each other. The second shield group 12 is configured by arranging a plurality of strip-shaped second magnetic shield members 10B at predetermined intervals so that their respective second longitudinal directions are parallel to each other.
In the magnetic shield panel 20, the first shield group 11 and the second shield group 12 are fixed to the base material 15 so that the first magnetic shield member 10A and the second magnetic shield member 10B are orthogonal to each other. For example. The first shield group 11 can be fixed to the base material 15 first, and then the second shield group 12 can be laminated on the first shield group 11 and fixed to the base material 15.
The first shield group 11 and the second shield group 12 may be fixed to the base material 15 by sandwiching the base material 15, and the first shield group 11 and the second shield group 12 are fixed to different base materials 15. , They may be bonded so that their longitudinal directions are orthogonal to each other. Further, the first magnetic shield member 10A can be regarded as a weft thread and the second magnetic shield member 10B can be regarded as a warp thread, and the first magnetic shield member 10A can be alternately laminated in a plain weave shape and fixed to the base material 15.

The first magnetic shield member 10A and the second magnetic shield member 10B are composed of the above-mentioned magnetic shield member 10, and each has a length L of 500 mm and a width W of 100 mm, respectively. The dimensions of the first magnetic shield member 10A and the second magnetic shield member 10B do not necessarily have to be the same, and can be set according to the shape of the magnetic shield panel 20 to be formed.

The base material 15 is preferably square in consideration of arranging and fixing the base material 15 in a tile shape on the wall surface or the like of the magnetic shield room, but it can be any shape according to the shape of the wall surface or the like.
The base material 15 may be a rigid synthetic resin material such as ABS (Acrylonitrile Butadiene Styrene) resin or acrylic resin, and may be a thin and flexible material such as a polyimide film or a PET (Polyethylene terephthalate) film, or may be adhered to both sides of the film. A double-sided tape coated with the agent can be used. When a flexible material such as PET film is used as the base material 15, it can be applied not only to a flat wall surface or the like but also to a wall surface or the like having a slightly curved surface. Not limited to an insulating material such as a synthetic resin, a metal material such as a thin plate of Cu or a Cu foil may be used. When a metal material is used as the base material 15, an eddy current is generated by a magnetic field in the direction perpendicular to the base material 15, and as a result, a loss due to the eddy current is generated, and as a result, a magnetic shielding effect is exhibited. The base material 15 is fixed at least when the first magnetic shield member 10A and the second magnetic shield member 10B are fixed, considering the workability when fixing the first magnetic shield member 10A and the second magnetic shield member 10B. It is preferable that the surface is flat.

The first magnetic shield member 10A and the second magnetic shield member 10B are fixed to the base material 15 using an adhesive. In order to fix the first magnetic shield member 10A and the second magnetic shield member 10B to the base material 15, other well-known methods such as double-sided tape may be used.
The base material 15 is provided with a fixing hole 13 for fixing the magnetic shield panel 20 by using a screw, for example, on the wall surface of the magnetic shield room. As shown in FIG. 7C, the fixing hole 13 is formed of the base material 15 in order to prevent an external force from being applied to the first magnetic shield member 10A and the second magnetic shield member 10B when the fixing hole 13 is drilled. It is opened in a place where the first magnetic shield member 10A and the second magnetic shield member 10B fixed to the above do not exist. Since the magnetic shield panel 20 in the present embodiment can be made lightweight, when the magnetic shield panel 20 is fixed to a wall surface or the like, it is fixed by using an adhesive or double-sided tape without screwing. You may do so. In that case, it is not necessary to open the fixing hole 13.

As shown in FIG. 7A, when the longitudinal direction of the first magnetic shield member 10A is arranged in the direction perpendicular to the direction of the magnetic field MF to be shielded indicated by the arrow, the magnetic field to be shielded. A gap is formed so as to block the direction of the MF. In such a case, the magnetic shielding effect is significantly reduced. On the other hand, as shown in FIG. 7B, a high magnetic shield is provided for the gap of the second magnetic shield member 10B formed along the direction parallel to the direction of the magnetic field MF to be shielded, which is indicated by the arrow. The effect is maintained.

When a gap is provided between the amorphous metal strips included in the first magnetic shield member 10A and the second magnetic shield member 10B as described above, direction dependence occurs with respect to the magnetic field MF to be shielded. Therefore, unless the direction of the magnetic field MF to be shielded can be limited to a specific direction, the first magnetic shield member 10A and the second magnetic shield member 10B can exert the magnetic shield effect in the two-dimensional direction. Are preferably arranged so as to intersect, typically orthogonally, to eliminate the orientation dependence of the magnetic field MF to be shielded. That is, according to the magnetic shield panel 20 of the present embodiment, as shown in FIG. 7C, the first magnetic shield member 10A with respect to the _{magnetic field MF 1 in the horizontal direction and the magnetic field MF 2 in the vertical direction.} The second magnetic shield member 10B mainly exerts a magnetic shield effect.

1 Amorphous magnetic layer 2 Co-based amorphous metal strip 2A Contact surface 2B Non-contact surface 5 Non-magnetic metal bonding layer 6 Aluminum alloy strip 7 Protrusion 8 Laminated body 10 Magnetic shield member 10A First magnetic shield member 10B No. (Ii) Magnetic shield member 11 1st shield group 12 2nd shield group 13 Fixing hole 15 Base material 20 Magnetic shield panel

Claims (7)

It consists of a laminate in which a plurality of amorphous magnetic layers and a plurality of non-magnetic metal bonding layers are alternately laminated.
Adjacent amorphous magnetic layer and non-magnetic metal bonding layer
A part of the surface layer of the non-magnetic metal bonding layer is press-fitted into the recess formed on the surface of the amorphous magnetic layer as a protrusion.
A magnetic shield member characterized by this. Each amorphous magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm.
Each non-magnetic metal bonding layer is made of aluminum or an aluminum alloy having a thickness of 10 to 30 μm.
The magnetic shield member according to claim 1. A laminating process of alternately laminating a plurality of amorphous magnetic layers and a plurality of non-magnetic metal bonding layers to obtain a laminated body,
A bonding process in which each amorphous magnetic layer and each non-magnetic metal bonding layer are bonded by pressurizing the laminate while heating to obtain a bonded body.
It is equipped with a heat treatment process for heat-treating the joint.
The joining process is
By applying pressure in the thickness direction of the bonded body in the range of 10 to 50 MPa at a temperature of 300 to 500 ° C. , one of the surface layers of the non-magnetic metal bonding layer is formed in the depression formed on the surface of the amorphous magnetic layer. The part becomes a protrusion and is press-fitted,
The heat treatment process is
Keep at a temperature of 300-500 ° C. for 0.1 to 100 hours in an inert gas atmosphere or atmosphere.
Manufacturing method of magnetic shield member. Each amorphous magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm.
Each non-magnetic metal bonding layer is made of aluminum or aluminum alloy with a thickness of 10 to 30 μm.
The thickness of the laminate is 1-3 mm,
The method for manufacturing a magnetic shield member according to claim 3. The joining process is performed in an inert gas atmosphere or in the atmosphere.
The time for applying pressure is 0.1 to 100 hours, or the total time for applying pressure and releasing pressure is 0.1 to 100 hours.
The joining process doubles as a heat treatment process,
The method for manufacturing a magnetic shield member according to claim 3 or 4. A group of first shields in which a plurality of first magnetic shield members having a predetermined length are arranged with a predetermined gap so that their first longitudinal directions are parallel to each other.
A second shield group in which a plurality of second magnetic shield members having a predetermined length are arranged with a predetermined gap so that their respective second longitudinal directions are parallel to each other.
The first shield group and the base material to which the second shield group is fixed are provided.
The first shield group and the second shield group are laminated so that the first longitudinal direction of the first magnetic shield member intersects the second longitudinal direction of the second magnetic shield member.
The first magnetic shield member and the second magnetic shield member are
It consists of a laminate in which a plurality of amorphous magnetic layers and a plurality of non-magnetic metal bonding layers are alternately laminated.
Adjacent amorphous magnetic layer and non-magnetic metal bonding layer
A part of the surface layer of the non-magnetic metal bonding layer is press-fitted into the recess formed on the surface of the amorphous magnetic layer as a protrusion.
A magnetic shield panel that features that. Each amorphous magnetic layer is made of a Co-based amorphous metal having a thickness of 10 to 30 μm.
Each non-magnetic metal bonding layer is made of aluminum or an aluminum alloy having a thickness of 10 to 30 μm.
The magnetic shield panel according to claim 6.

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