WO2023243697A1

WO2023243697A1 - Multilayer soft magnetic alloy thin strip and method for producing same, and laminated core and method for producing same

Info

Publication number: WO2023243697A1
Application number: PCT/JP2023/022331
Authority: WO
Inventors: 仲男森次; 政己井上; 尚哉江良; 伸野口
Original assignee: 株式会社プロテリアル
Priority date: 2022-06-17
Filing date: 2023-06-15
Publication date: 2023-12-21

Abstract

The present invention provides a multilayer soft magnetic alloy thin strip which is obtained by staking a plurality of soft magnetic alloy thin strips having a thickness of 10 µm to 50 µm upon each other, wherein: a resin layer is arranged between the soft magnetic alloy thin strips; and the resin layer contains a resin that has a melting point Tm of 80°C to 170°C and a thermal decomposition initiation temperature of 360°C or more.

Description

Multilayer soft magnetic alloy ribbon and its manufacturing method, and laminated core and its manufacturing method

The present disclosure relates to a multilayer soft magnetic alloy ribbon and a method for manufacturing the same, and a laminated core and a method for manufacturing the same.

A soft magnetic alloy ribbon made of soft magnetic alloy materials such as Fe-based amorphous alloys and Fe-based nanocrystalline alloys is manufactured by rapidly cooling and solidifying a molten alloy. A typical manufacturing method is to discharge a molten alloy onto a rotating cooling roll, rapidly cool it, and solidify it to obtain a ribbon-shaped soft magnetic alloy ribbon. Fe-based amorphous alloy ribbons and Fe-based nanocrystalline alloy ribbons obtained by this method are only thin, with a thickness of about 10 to 50 μm. These soft magnetic alloy ribbons (Fe-based amorphous alloy ribbons, Fe-based nanocrystalline alloy ribbons, etc.) have excellent magnetic properties (e.g., low iron loss, high saturation magnetic flux density), and can be used in various cores. It is used as a material.

When making a core from a soft magnetic alloy ribbon, there are two methods: one is to wind it to make a circumferential core, and the other is to make individual pieces by cutting or punching, and then stack them to make a laminated core. be. Demand for laminated cores is increasing due to the flexibility in core shapes.

When manufacturing a laminated core, if a thin (approximately 10 to 50 μm) soft magnetic alloy ribbon is used for processing, the thinness of the soft magnetic alloy ribbon results in poor handling and the need to manufacture each piece into individual pieces. There is a problem with the number of steps involved in the work and lamination work, so a method is to prepare a multilayer soft magnetic alloy ribbon by laminating multiple soft magnetic alloy ribbons, and then use the multilayer soft magnetic alloy ribbon to manufacture a core. is also used.

For example, JP 2021-002553 discloses a soft magnetic amorphous alloy ribbon, and a resin layer disposed on at least one of a pair of opposing main surfaces of the soft magnetic amorphous alloy ribbon, and the resin layer A magnetic material using a polyamide-imide resin having a coefficient of linear expansion of 40 ppm/° C. or less is disclosed.

When soft magnetic alloy ribbons are laminated or processed, stress is applied to them and their magnetic properties tend to deteriorate. As a method of restoring the deteriorated magnetic properties, there is a method of performing heat treatment. For example, heat treatment may be performed at a temperature of 300 degrees or higher.

Multilayer soft magnetic alloy ribbons are often joined together via a resin layer, but heat-resistant resins have been used in consideration of the heat treatment described above. For example, in the case of a polyamide-imide resin disclosed in JP-A-2021-002553, it is stated that it is preferable to have a glass transition temperature of 250° C. or higher. In addition, in the case of polyamide-imide resin, it is necessary to maintain the heat-pressed state for several minutes, and when laminating and joining multilayer soft magnetic alloy ribbons, a batch-type joining method is required. Therefore, there was a problem in terms of productivity.

Soft magnetic alloy ribbons are laminated or wound and used for transformers, motor cores, and the like. These products are required to be low priced. Therefore, the multilayer soft magnetic alloy ribbon is also required to be low in cost. In addition, multilayer soft magnetic alloy ribbons are often processed to form cores, and during processing, in order to prevent the soft magnetic alloy ribbons from peeling off, the soft magnetic alloy ribbons are is required to have high peel strength.
An object of the present disclosure is to provide a multilayer soft magnetic alloy ribbon that is low-cost and has high peel strength.

<1>
A multilayer soft magnetic alloy ribbon in which a plurality of soft magnetic alloy ribbons having a thickness of 10 to 50 μm are laminated,
A resin layer is arranged between the soft magnetic alloy ribbons,
The resin layer is a multilayer soft magnetic alloy ribbon containing a resin having a melting point Tm of 80° C. or higher and 170° C. or lower and a thermal decomposition initiation temperature of 360° C. or higher.
<2>
In the multilayer soft magnetic alloy ribbon, the peel strength of the soft magnetic alloy ribbon at one end in the lamination direction of the soft magnetic alloy ribbon is 0.01 N/mm or more, the multilayer soft magnetic alloy thin ribbon according to <1>. band.
<3>
The multilayer soft magnetic alloy ribbon according to <1> or <2>, wherein the soft magnetic alloy ribbon contains an amorphous alloy or a nanocrystalline alloy.
<4>
The multilayer soft magnetic alloy ribbon according to any one of <1> to <3>, wherein a peak of OH antisymmetric stretching is detected when the resin is subjected to Raman spectroscopy.
<5>
The multilayer soft magnetic alloy ribbon according to any one of <1> to <4>, wherein the resin contains a polymer containing an olefin as a constituent unit.
<6>
A step of preparing a plurality of soft magnetic alloy ribbons;
forming a resin layer on at least one surface of the soft magnetic alloy ribbon, and stacking the plurality of soft magnetic alloy ribbons so that the resin layer is disposed between the soft magnetic alloy ribbons;
Pressing and heating the laminated soft magnetic alloy ribbons,
The method for producing a multilayer soft magnetic alloy ribbon, wherein the resin layer includes a resin having a melting point Tm of 80°C or more and 170°C or less and a thermal decomposition initiation temperature of 360°C or more.
<7>
In the step of pressurizing and heating the laminated soft magnetic alloy ribbons,
The method for producing a multilayer soft magnetic alloy ribbon according to <6>, wherein the laminated soft magnetic alloy ribbon is passed between a pair of heated rolls.
<8>
The method for producing a multilayer soft magnetic alloy ribbon according to <7>, wherein the temperature of the heated pair of rolls is equal to or higher than the melting point Tm and equal to or lower than 350°C.
<9>
A laminated core comprising a laminated body of soft magnetic alloy ribbons,
The soft magnetic alloy ribbon has a thickness of 10 to 50 μm, and a resin layer is disposed between the soft magnetic alloy ribbons, and the resin layer has a melting point Tm of 80°C or more and 170°C or less, and a thermal decomposition start temperature. A laminated core containing a resin whose temperature is 360°C or higher.
<10>
The laminated core according to <9>, wherein the soft magnetic alloy ribbon contains an amorphous alloy or a nanocrystalline alloy.
<11>
The laminated core according to <9> or <10>, wherein a peak of OH antisymmetric stretching is detected when the resin is subjected to Raman spectroscopy.
<12>
The laminated core according to any one of <9> to <11>, wherein the resin contains a polymer containing an olefin as a constituent unit.
<13>
Processing the multilayer soft magnetic alloy ribbon according to any one of <1> to <4> to produce a multilayer core piece;
A method for manufacturing a laminated core, comprising the step of laminating the multilayer core pieces.
<14>
The method for manufacturing a laminated core according to <13>, wherein the processing of the multilayer soft magnetic alloy ribbon is cutting or punching.

According to the present disclosure, a relatively inexpensive resin can be used and costs can be reduced. Further, according to the present disclosure, it is possible to provide a multilayer soft magnetic alloy ribbon with high peel strength. Further, according to the present disclosure, a method for manufacturing the multilayer soft magnetic alloy ribbon can be provided. Further, according to the present disclosure, a laminated core using the multilayer soft magnetic alloy ribbon can be provided.

FIG. 2 is a plan view of a multilayer core piece according to an embodiment of the present disclosure. FIG. 1 is a perspective view of a laminated core according to an embodiment of the present disclosure. FIG. 3 is a diagram showing core loss before and after heat treatment according to an embodiment of the present disclosure. 3 is a diagram showing the results of Raman spectroscopic analysis of the resin peeled off from the Fe-based amorphous alloy foil strip of Sample 5 of Example 1. FIG. FIG. 3 is a diagram showing the results of Raman spectroscopic analysis of the resin peeled off from the resin layer of the Fe-based amorphous alloy ribbon after heat-treating Sample 5 of Example 1 at 330° C.

[Multilayer soft magnetic alloy ribbon]
A multilayer soft magnetic alloy ribbon according to an embodiment of the present disclosure is a multilayer soft magnetic alloy ribbon in which a plurality of soft magnetic alloy ribbons having a thickness of 10 to 50 μm are laminated, and the soft magnetic alloy ribbon has a thickness of 10 to 50 μm. A resin layer is disposed, and the resin layer includes a resin having a melting point Tm of 80°C or more and 170°C or less and a thermal decomposition start temperature of 360°C or more.

In the multilayer soft magnetic alloy ribbon according to an embodiment of the present disclosure, two or more layers of the soft magnetic alloy ribbon are laminated. The number of laminated soft magnetic alloy ribbons can be determined depending on the purpose. When winding a multilayer soft magnetic alloy ribbon, if the number of laminated layers is too large, winding may become difficult. Therefore, the number of laminated layers is preferably 25 layers or less, more preferably 20 layers or less, even more preferably 15 layers or less, and particularly preferably 10 layers or less. Further, the number of laminated layers is two or more layers, preferably three or more layers, more preferably four or more layers, and even more preferably five or more layers.

A resin layer is arranged between the soft magnetic alloy ribbons.
The resin layer functions as an adhesive layer and can join adjacent soft magnetic alloy ribbons.

The resin layer includes a resin (hereinafter also referred to as "specific resin") having a melting point Tm of 80° C. or higher and 170° C. or lower and a thermal decomposition initiation temperature of 360° C. or higher. The resin layer may contain components other than the specific resin. Examples of other components include dimethylaminoethanol, isopropyl alcohol, and carboxylic acid amide. The resin layer may contain other resins than the specific resin, but from the viewpoint of obtaining a function as an adhesive layer, it is preferable not to contain other resins. That is, it is preferable that the resin contained in the resin layer is only the specific resin.

The melting point of the specific resin is measured using a simultaneous differential thermogravimetric measurement device. Specifically, the measurement is performed in the presence of an inert gas, and the temperature corresponding to the endothermic peak of the obtained DTA curve is defined as the melting point.

The thermal decomposition start temperature of a specific resin is measured using a simultaneous differential thermogravimetric measurement device. Specifically, the measurement is performed in the presence of an inert gas, and the temperature corresponding to the point at which the obtained TG curve loses linearity and turns downward, and the DTA curve loses linearity or turns from rising to falling is determined. This is the starting temperature of thermal decomposition.

The specific resin has a melting point Tm of 80° C. or more and 170° C. or less, and the heat treatment temperature of the soft magnetic alloy ribbon (for example, 300° C. to 350° C.) exceeds the melting point Tm of the specific resin. However, since the thermal decomposition start temperature of the specific resin is 360°C or higher, the resin will not disappear even if it is heat-treated at, for example, 350°C. Therefore, when the temperature returns to room temperature after heat treatment, the resin layer containing the specific resin functions as an adhesive layer and enables bonding between the soft magnetic alloy ribbons. Further, it is preferable that the specific resin has a 5% weight loss temperature of around 400°C or higher than 400°C. Moreover, it is preferable that the specific resin has a glass transition temperature Tg of 0° C. or lower.

The 5% weight loss temperature of the specific resin is measured using a simultaneous differential thermogravimetric measurement device. Specifically, the temperature is heated from 30° C. to 800° C. at a temperature increase rate of 10° C./min, and the temperature at which a 5% weight loss is confirmed is defined as the 5% weight loss temperature.

The glass transition temperature of a specific resin is measured using a simultaneous differential thermogravimetric measurement device.

The specific resin is a resin that can be heat treated. Moreover, instead of a heat-resistant resin, a resin that can be used at a low cost can be used.

The number of specific resins contained in the resin layer may be only one, or two or more.

It is preferable that the specific resin contains a polymer containing an olefin as a structural unit. Examples of olefins include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, isopentene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-decene, 1- Examples include hexadecene, 1-octadecene, 1-eicosene, and the like. Examples of the specific resin include polyethylene resin and polypropylene resin. Polymers consisting of olefin as a constituent unit, typified by polyethylene resin and polypropylene resin, are called polyolefins.

Since polyolefin is made of carbon (C) and hydrogen (H), even if it is burned, it becomes water (H ₂ O) and carbon dioxide gas (CO ₂ ), making it an environmentally friendly resin. Furthermore, progress is being made in the development of bioplastics manufactured from raw materials such as sugarcane. By using bioethylene and biopolypropylene, a more environmentally friendly multilayer soft magnetic alloy ribbon can be obtained.

Furthermore, when the specific resin is subjected to Raman spectroscopy, it is preferable that a peak of OH antisymmetric stretching is detected. Raman spectroscopy is performed using a Raman spectrometer.

In the multilayer soft magnetic alloy ribbon according to the present disclosure, it is preferable that the peel strength of the soft magnetic alloy ribbon at one end in the lamination direction of the soft magnetic alloy ribbon is 0.01 N/mm or more. More preferably, it is 0.03 N/mm or more. By having this peel strength of 0.01 N/mm or more, it is possible to suppress peeling of the soft magnetic alloy ribbon from the multilayer soft magnetic alloy ribbon. For example, when a multilayer soft magnetic alloy ribbon is punched, it is possible to prevent the soft magnetic alloy ribbon from peeling off at the ends of the punched pieces. Further, by having a peel strength of 0.03 N/mm or more, the effect of suppressing peeling of the soft magnetic alloy ribbon can be further enhanced.

This peel strength is determined by, for example, preparing a multilayer soft magnetic alloy ribbon with a width of 30 mm, performing a peel test on the outermost soft magnetic alloy ribbon, and measuring the force (N) when peeled off. When the value of this force is set to X (N), it is written as X (N/30 mm). The value obtained by dividing this force value X (N) by the width of the soft magnetic alloy ribbon of 30 mm is defined as the peel strength X/30 (N/mm). In the case of a multilayer soft magnetic alloy ribbon having a width other than 30 mm, the width can be determined by conducting a similar test and dividing by the width.

The resin layer preferably has a thickness of 2 μm or less, more preferably 1 μm or less, even more preferably 0.9 μm or less, and particularly preferably 0.8 μm or less. By making the resin layer thinner, the space factor of the laminated core constructed using multilayer soft magnetic alloy ribbons can be increased. Moreover, since the resin layer contains a specific resin, it is possible to configure a resin layer with high peel strength even if it is thin. For example, the resin layer may have a thickness of 1 μm or less and a peel strength of 0.01 N/mm or more. Further, the thickness of the resin layer is preferably 0.2 μm or more, more preferably 0.3 μm or more, and still more preferably 0.4 μm or more.
Here, the thickness of the resin layer is determined by stacking the desired number (Y sheets) of soft magnetic alloy ribbons without a resin layer, and stacking the same number (Y sheets) of soft magnetic alloy ribbons with a resin layer. It is calculated from the difference in the thickness of the multilayer soft magnetic alloy ribbon. Specifically, the value obtained by dividing (thickness of the number Y of multilayer soft magnetic alloy ribbons with a resin layer) - (thickness of the number Y of multilayer soft magnetic alloy ribbons without a resin layer) by Y-1. means.

Preferably, the soft magnetic alloy ribbon includes an amorphous alloy or a nanocrystalline alloy. Although the soft magnetic alloy ribbon may contain an alloy other than an amorphous alloy or a nanocrystalline alloy, it is preferably made of an amorphous alloy or a nanocrystalline alloy from the viewpoint of exhibiting good soft magnetic properties. The amorphous alloy ribbon made of an amorphous alloy is preferably an Fe-based amorphous alloy ribbon. Furthermore, the nanocrystalline alloy ribbon made of a nanocrystalline alloy is preferably a Fe-based nanocrystalline alloy ribbon.
The soft magnetic alloy ribbon may be an amorphous alloy ribbon or a nanocrystalline alloy ribbon.

The thickness of the soft magnetic alloy ribbon is 10 to 50 μm, preferably 14 to 35 μm.
The thickness of the soft magnetic alloy ribbon is measured using a micrometer.

[Method for producing multilayer soft magnetic alloy ribbon]
A method for manufacturing a multilayer soft magnetic alloy ribbon according to an embodiment of the present disclosure will be described.
A method for manufacturing a multilayer soft magnetic alloy ribbon according to an embodiment of the present disclosure includes the steps of preparing a plurality of soft magnetic alloy ribbons, forming a resin layer on at least one surface of the soft magnetic alloy ribbon, and forming a resin layer on at least one surface of the soft magnetic alloy ribbon. The method includes the steps of stacking a plurality of soft magnetic alloy ribbons so as to be arranged between the magnetic alloy ribbons, and pressing and heating the laminated soft magnetic alloy ribbons.

First, a plurality of soft magnetic alloy ribbons are prepared. Preferred embodiments of the soft magnetic alloy ribbon are as described above. Here, it is preferable to prepare a wound body in which a soft magnetic alloy ribbon is wound into a coil shape.
Then, a resin layer is formed on at least one surface of each soft magnetic alloy ribbon. The soft magnetic alloy ribbon has a flat plate shape and has two opposing main surfaces. The resin layer may be formed only on one main surface, or the resin layer may be formed on both main surfaces. Note that forming the resin layer only on one main surface is advantageous in improving the space factor.
In the case of a wound body in which the soft magnetic alloy thin ribbon is wound into a coil, the soft magnetic alloy thin ribbon can be unwound from the wound body and a resin layer can be formed on one or both surfaces of the soft magnetic alloy thin ribbon. For example, the resin layer can be formed using a gravure coater.

The resin layer contains a specific resin. Preferred embodiments of the specific resin are as described above. As the specific resin, for example, polyethylene resin or polypropylene resin can be used.
The resin layer is preferably formed using an aqueous dispersion containing a specific resin. For example, the resin layer can be formed using an aqueous dispersion obtained by mixing the polyolefin particles in a dispersion medium such as water.

By forming the resin layer using an aqueous dispersion containing a specific resin, there is no need to treat oil, making handling easier, improving productivity, and reducing manufacturing costs.

Next, a plurality of soft magnetic alloy ribbons are laminated so that the resin layer is disposed between the soft magnetic alloy ribbons.
A plurality of soft magnetic alloy ribbons each having a resin layer formed thereon are stacked one on top of the other.
For example, a soft magnetic alloy ribbon with a resin layer formed on one side is laminated in the following order: alloy ribbon, resin layer, alloy ribbon, resin layer, and a multilayer body with a resin layer formed on the top surface. A multilayer soft magnetic alloy ribbon can be constructed by laminating a soft magnetic alloy ribbon on which no resin layer is formed.
Then, the laminated soft magnetic alloy ribbons are pressurized and heated. Thereby, a multilayer soft magnetic alloy ribbon in which a plurality of soft magnetic alloy ribbons are joined to each other via a resin layer can be obtained.

For example, it is possible to prepare a plurality of wound bodies of soft magnetic alloy thin ribbons, unwind the soft magnetic alloy thin ribbons from the wound body, and form the resin layer while transporting the soft magnetic alloy thin ribbons.
Further, the soft magnetic alloy ribbons on which the resin layer is formed can be laminated and joined while being conveyed.
In other words, the process can be performed continuously while conveying the soft magnetic alloy ribbon.
Because the resin layer contains a specific resin, it is possible to join soft magnetic alloy ribbons by applying pressure and heating in a short time, and the soft magnetic alloy ribbons stacked in multiple layers can be continuously conveyed through the resin layer. However, by applying pressure and heating, a bonded multilayer soft magnetic alloy ribbon can be obtained.
For example, in the process of pressurizing and heating laminated soft magnetic alloy ribbons, by passing the laminated soft magnetic alloy ribbons between a pair of heated rolls, the bonded multilayer soft magnetic alloy ribbons and can do.
Furthermore, a bonded multilayer soft magnetic alloy ribbon can also be obtained by sandwiching it between heated plates.
At this time, it is preferable that the temperature of the roll and the temperature of the heated plate be greater than or equal to the melting point Tm of the resin and less than or equal to 350°C.

Furthermore, a wound body of the multilayer soft magnetic alloy ribbon can also be obtained by winding the multilayer soft magnetic alloy ribbon around a roll.
Further, according to the present disclosure, the multilayer soft magnetic alloy ribbon can be manufactured on an integrated line called roll-to-roll, which is excellent in mass productivity.

A preferred embodiment of the number of laminated soft magnetic alloy ribbons in the multilayer soft magnetic alloy ribbon is as described above.

[Laminated core]
The multilayer soft magnetic alloy ribbon of the present disclosure can be processed into individual pieces of a predetermined shape by cutting, punching, or the like. Then, the individual pieces can be further laminated to form a laminated core.

A laminated core according to an embodiment of the present disclosure is a laminated core including a laminated body of soft magnetic alloy ribbons, the soft magnetic alloy ribbons having a thickness of 10 to 50 μm, and between the soft magnetic alloy ribbons. A resin layer is arranged, and the resin layer contains a specific resin. Preferred embodiments of the soft magnetic alloy ribbon and the specific resin are as described above.

The laminated core is used as the core of various transformers and coils, and can also be used as a motor core. Note that the laminated core may be a combination of a plurality of different magnetic materials. Examples of the magnetic material include an amorphous alloy, a nanocrystalline alloy ribbon, and an electromagnetic steel sheet.

The magnetic properties of soft magnetic alloy ribbons may deteriorate due to stress. Especially after processing, deterioration of magnetic properties may occur. The multilayer soft magnetic alloy ribbon of the present disclosure can be heat treated, and heat treatment can be performed to recover the deterioration of magnetic properties caused by stress such as processing.

[Method for manufacturing laminated core]
A method for manufacturing a laminated core according to an embodiment of the present disclosure includes a step of processing a multilayer soft magnetic alloy ribbon according to an embodiment of the present disclosure to produce a multilayer core piece, a step of laminating the multilayer core pieces, including.

The method for processing the multilayer soft magnetic alloy ribbon is not particularly limited, but cutting or punching is preferable.

Examples of the present disclosure will be described below, but the present disclosure is not limited to the following examples.

[Example 1]
As the soft magnetic alloy ribbon, an Fe-based amorphous alloy ribbon (HB1M manufactured by Proterial Co., Ltd. (former Hitachi Metals, Ltd.)) was used. Five coiled bodies of Fe-based amorphous alloy ribbons each having a width of 30 mm and a thickness of 25 μm were prepared. An aqueous dispersion of polyethylene resin was applied to one surface of the Fe-based amorphous alloy ribbon unwound from the four wound bodies using a gravure coater to a thickness of 1 to 1.5 μm to form a resin layer. Formed. This polyethylene resin had a melting point Tm of about 100°C and a thermal decomposition initiation temperature of about 400°C. In addition, the melting point is the temperature at the endothermic peak of the DTA curve when measured under an inert gas using a simultaneous differential thermogravimetric measurement device, and the thermal decomposition start temperature is the temperature at which the TG curve loses its linearity and turns downward. This is the temperature at which the DTA curve loses its linearity or changes from rising to falling.

In this example, the Fe amorphous alloy ribbon on which the resin layer was formed was wound up into four wound bodies. Next, each Fe-based amorphous alloy ribbon is unwound from the wound body of the four Fe-based amorphous alloy ribbons on which the resin layer has been formed, and while being conveyed, the alloy ribbon, the resin layer, the alloy ribbon, and the resin are unwound. layer, alloy ribbon, resin layer, alloy ribbon, and resin layer in this order, and on top of the upper resin layer, a Fe-based amorphous alloy ribbon (the fifth roll) with no resin layer formed. The Fe-based amorphous alloy ribbons unwound from the rotating body were laminated to form a multilayer soft magnetic alloy ribbon consisting of five layers of Fe-based amorphous alloy ribbons. Here, the five-layer Fe-based amorphous alloy ribbon is produced in a transported state. Then, the above five-layer Fe-based amorphous alloy thin strip is passed between a pair of rolls whose roll temperature is set at 80°C to 200°C, and pressure and heating are applied to form the five-layered Fe-based amorphous alloy thin strip. A multilayer soft magnetic alloy ribbon in which the strips are joined to each other was fabricated. This multilayer soft magnetic alloy ribbon was wound onto a roll. The conveying speed of the Fe-based amorphous alloy ribbon when passing between the pair of rolls was 3.5 m/min.

Table 1 shows the relationship between roll temperature, peel strength, and resin layer thickness in Example 1.
The resin layer thickness is measured by measuring the thickness of a multilayer soft magnetic alloy ribbon consisting of five layers of Fe-based amorphous alloy ribbon. Further, five layers of Fe-based amorphous alloy ribbons without a resin layer are laminated, and the thickness thereof is measured. The difference in thickness was divided by 4. Note that the thickness was measured using a micrometer, and the measurements were taken at 10 locations and the average value was taken as the average value.
The peel strength was measured by manually turning over the outermost Fe-based amorphous alloy ribbon of the multilayer soft magnetic alloy ribbon. Next, punch a hole in the rolled part using a hand punch. Next, hook the sensor part of the autograph and the attached hook into the hole. Then, the force (N) when the sensor is moved at a constant speed and peeled off is read. The read value was defined as the peel strength in units of N/30 mm, and the value obtained by dividing the read value by the width of 30 mm was defined as the peel strength in units of N/mm. Table 1 shows the peel strength values in N/30 mm and N/mm.

It can be seen that the peel strength increases as the roll temperature increases. The roll temperature can be set according to the required peel strength. In particular, when the roll temperature was 100° C., the peel strength was 0.01 N/mm or more, and sufficient peel strength was obtained. Further, when the roll temperature was 120° C. or higher, a peel strength of 0.03 N/mm or higher was obtained, and even more sufficient peel strength was obtained.
In addition, the resin layer thickness is 1.0 μm or less in each case, and the resin layer can be made sufficiently thin, and the effect of increasing the space factor can be expected. In particular, Samples 2 to 5 had a thin resin layer thickness of 0.75 μm and a sufficient peel strength, making it possible to obtain a multilayer soft magnetic alloy ribbon with a thin resin layer and high peel strength.

In the multilayer soft magnetic alloy ribbon of sample 5, Raman spectroscopic analysis of the resin peeled off from between the layers of the Fe-based amorphous alloy ribbon was conducted. The results are shown in FIG. Further, FIG. 5 shows the results of Raman spectroscopy of the resin peeled off from between the layers of the Fe-based amorphous alloy foil strip in the multilayer soft magnetic foil strip obtained by further heat-treating Sample 5 at 330°C.
In FIGS. 4 and 5, the peak existing around 3640 cm ⁻¹ is a peak indicating OH antisymmetric stretching, and when the resin of the present disclosure was subjected to Raman spectroscopy, a peak indicating OH antisymmetric stretching was detected.

[Example 2]
A laminated core for a motor was produced using the sample of Example 1.
Using the multilayer soft magnetic alloy ribbon (5-layer Fe-based amorphous alloy ribbon) of Sample 5 of Example 1, a multilayer core piece 1 having the shape shown in FIG. 1 was produced by punching. This multilayer core piece 1 consists of five layers of Fe-based amorphous alloy ribbons. This multilayer core piece 1 was punched using a punch processed into the shape of a core piece and a die having a hole into which the punch could be inserted. This multilayer core piece 1 is also a laminate of soft magnetic alloy ribbons.

A laminated core 2 as shown in FIG. 2 was produced by stacking 360 of these multilayer core pieces 1. This laminated core 2 has 1800 Fe-based amorphous alloy ribbons laminated. Each multilayer core piece 1 was bonded using a one-component thermosetting acrylic adhesive having a viscosity of 50 mPa·s. Bonding was performed at 170° C. for 2 hours.
Six laminated cores 2 were produced and combined to produce a cylindrical laminated core for a motor with an outer diameter of 50 mm and an inner diameter of 26 mm. This can be used as a stator for a motor.

The multilayer soft magnetic alloy ribbon of the present disclosure can be punched into multilayer core pieces, and after punching, even if the multilayer core pieces are laminated to produce a laminated core, no shape defects will occur, and it can be used as a laminated core. It turned out to be. Moreover, no peeling of the soft magnetic alloy ribbon occurred after punching.
The multilayer soft magnetic alloy ribbon of the present disclosure is formed into a multilayer core piece using a processing method such as cutting or punching, and the multilayer core pieces are stacked to produce a laminated core. It can be used for various purposes such as choke coils. Note that the laminated core can be fixed to the housing by known means such as adhesion or potting.

[Confirmation of heat treatability of the resin of the present disclosure]
As the soft magnetic alloy ribbon, an Fe-based amorphous alloy ribbon (HB1M manufactured by Proterial Co., Ltd. (former Hitachi Metals, Ltd.)) was used. A wound body in which a Fe-based amorphous alloy ribbon having a width of 50 mm and a thickness of 25 μm was wound into a coil was prepared. A resin layer was formed by applying an aqueous dispersion of polyethylene resin to a thickness of 1 to 1.5 μm using a gravure coater on one surface of the Fe-based amorphous alloy ribbon unwound from the roll. After drying the resin layer, it was punched out into a ring shape with an outer diameter of 43 mm and an inner diameter of 25 mm.
Further, the same Fe-based amorphous alloy ribbon was punched out into a ring shape with an outer diameter of 43 mm and an inner diameter of 25 mm without forming a resin layer.

Experimental example 1
Thirty ring-shaped samples on which no resin layer was formed were stacked. A ring-shaped core sample was produced without bonding the stacked samples.
Experimental example 2
Thirty ring-shaped samples each having a resin layer formed thereon were laminated. Then, it was heated to 150° C. under a pressure of 0.1 MPa to produce a ring-shaped core sample to which each Fe-based amorphous alloy ribbon was joined.
Experimental example 3
The ring-shaped core sample of Experimental Example 2 was heat-treated at 330° C. in a nitrogen atmosphere. Note that after the heat treatment, the Fe-based amorphous alloy ribbons were in a joined state, and the shape before the heat treatment was maintained.

Core loss at 1 kHz and 1 T was measured using the core samples of Experimental Examples 1, 2, and 3. The measuring device used was Iwatsu SY-8232, and the primary and secondary windings were 30 turns. The results are shown in Table 2 and FIG. As shown in Table 2 and FIG. 3, the core sample (Experimental Example 2) in which multilayer soft magnetic alloy ribbons were bonded had worsened core loss. This is thought to be caused by the stress caused by the formation and bonding of the resin layer. However, as shown in Experimental Example 3, core loss could be almost recovered by performing stress-relaxing heat treatment.
It can be seen that according to the resin of the present disclosure, heat treatment for stress relaxation is possible.

Note that the disclosure of Japanese Patent Application No. 2022-097745 filed on June 17, 2022 is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards mentioned herein are incorporated by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference. , incorporated herein by reference.

Claims

A multilayer soft magnetic alloy ribbon in which a plurality of soft magnetic alloy ribbons having a thickness of 10 to 50 μm are laminated,
A resin layer is arranged between the soft magnetic alloy ribbons,
The resin layer is a multilayer soft magnetic alloy ribbon containing a resin having a melting point Tm of 80° C. or higher and 170° C. or lower and a thermal decomposition initiation temperature of 360° C. or higher.
The multilayer soft magnetic alloy thin strip according to claim 1, wherein in the multilayer soft magnetic alloy thin ribbon, the peel strength of the soft magnetic alloy thin strip at one end in the lamination direction of the soft magnetic alloy thin ribbon is 0.01 N/mm or more. band.
The multilayer soft magnetic alloy ribbon according to claim 1 or 2, wherein the soft magnetic alloy ribbon contains an amorphous alloy or a nanocrystalline alloy.
The multilayer soft magnetic alloy ribbon according to claim 1 or 2, wherein a peak of OH antisymmetric stretching is detected when the resin is subjected to Raman spectroscopy.
The multilayer soft magnetic alloy ribbon according to claim 1 or 2, wherein the resin contains a polymer containing an olefin as a constituent unit.
A step of preparing a plurality of soft magnetic alloy ribbons;
forming a resin layer on at least one surface of the soft magnetic alloy ribbon, and stacking the plurality of soft magnetic alloy ribbons so that the resin layer is disposed between the soft magnetic alloy ribbons;
Pressing and heating the laminated soft magnetic alloy ribbons,
The method for producing a multilayer soft magnetic alloy ribbon, wherein the resin layer includes a resin having a melting point Tm of 80°C or more and 170°C or less and a thermal decomposition initiation temperature of 360°C or more.
In the step of pressurizing and heating the laminated soft magnetic alloy ribbons,
7. The method for producing a multilayer soft magnetic alloy ribbon according to claim 6, wherein the laminated soft magnetic alloy ribbon is passed between a pair of heated rolls.
The method for manufacturing a multilayer soft magnetic alloy ribbon according to claim 7, wherein the temperature of the pair of heated rolls is higher than or equal to the melting point Tm and lower than 350°C.
A laminated core comprising a laminated body of soft magnetic alloy ribbons,
The soft magnetic alloy ribbon has a thickness of 10 to 50 μm, and a resin layer is disposed between the soft magnetic alloy ribbons, and the resin layer has a melting point Tm of 80°C or more and 170°C or less, and a thermal decomposition start temperature. A laminated core containing a resin whose temperature is 360°C or higher.
The laminated core according to claim 9, wherein the soft magnetic alloy ribbon includes an amorphous alloy or a nanocrystalline alloy.
The laminated core according to claim 9 or 10, wherein a peak of OH antisymmetric expansion and contraction is detected when the resin is subjected to Raman spectroscopy.
The laminated core according to claim 9 or 10, wherein the resin contains a polymer containing an olefin as a constituent unit.
Processing the multilayer soft magnetic alloy ribbon according to claim 1 to produce a multilayer core piece;
A method for manufacturing a laminated core, comprising the step of laminating the multilayer core pieces.
The method for manufacturing a laminated core according to claim 13, wherein the processing of the multilayer soft magnetic alloy ribbon is cutting or punching.