JPH0992519A - Magnetic element and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize and thin a magnetic element by a method wherein the magnetic element is composed of an alloy thin band, alloy wire or alloy thin film wherein a region containing more than a specific amount of fine nano- crystalline particle structure having a particle diameter smaller than a specific value and another region containing more than a specific amount of amorphous phase are mixed with each other. SOLUTION: A magnetic element is composed of an alloy thin band, alloy wire or alloy thin film wherein a region containing at least 50% of fine nano- crystalline particles having a diameter not exceeding 50nm and another region containing at least 50% of amorphous phase are mixed with each other. In such a composition, the alloy thin band, alloy wire or alloy thin film contain Fe, at least one kind of element selected from Cu and Au, and at least one element selected from Ti, V, Zr, Nb, Mo, Hf, Ta, and W as an essential components. On the other hand, this magnetic element is to be manufactured by locally heating the amorphous alloy thin band, wire or thin film to be fine- crystallized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic element suitable for various sensors such as an anti-theft sensor, an article identification sensor and a magnetostrictive sensor, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, soft magnetic alloy ribbons such as permalloy alloy and amorphous alloy, wires and the like have been used as magnetic materials used in anti-theft sensors, article identification sensors and the like. Recently, Fe-based nanocrystalline soft magnetic alloys composed of ultrafine crystal grains represented by the Fe-Cu-Nb-Si-B system as shown in Japanese Patent Publication No. 4-4393 have excellent soft magnetic properties. It has been reported that it can be an excellent soft magnetic material that exhibits characteristics and has a small magnetostriction and a small change with time. Also,
It is also reported that these alloys are suitable for current sensor materials and the like.

[0003]

The nanocrystalline soft magnetic alloy is produced by a liquid quenching method such as a single roll method or a twin roll method in the case of producing a ribbon, and a rotating liquid spinning method in the case of a wire. A typical method is to produce an amorphous alloy ribbon or wire and then heat-treat it to crystallize it to produce an alloy ribbon or an alloy wire in which fine nano-crystal grains with a grain size of 50 nm or less occupy at least 50% of the structure. is there. However, the nanocrystalline alloy is excellent in soft magnetic properties but small in magnetostriction, and is not suitable for a sensor that utilizes magnetostriction.

On the other hand, the Fe-based amorphous alloy has a large magnetostriction and is suitable for a sensor utilizing magnetostriction, but when used in a delay line or the like, the soft magnetic characteristics are inferior to those of the nanocrystalline alloy, and therefore a large magnetic field for magnetization is generated. Need to be applied. When used as an identification sensor or the like, conventionally, an article is identified based on a difference in detection signal by combining amorphous ribbons or wires having different magnetic characteristics or dimensions. However, in this method, since a plurality of materials are arranged and used, it is difficult to miniaturize, the work becomes complicated when manufacturing the magnetic element for the sensor, and the combination of these materials is changed. In addition, it is necessary to prepare materials of various materials or dimensions in advance, it is difficult to arbitrarily change the rough alignment pattern, and there is a problem that the combination is limited to some extent. In addition, there is also a method of applying a bias magnetic field with a permanent magnet or a semi-hard magnet in a magnetic element for a sensor. Conventionally, a permanent magnet or a semi-hard magnet was separately manufactured and used by attaching it to a sensor material.
There are problems that it is difficult to reduce the thickness and that the number of manufacturing processes increases.

[0005]

The present invention has been made in order to solve the above problems, in which a region in which fine nano-crystal grains having a grain size of 50 nm or less occupy at least 50% of the structure and an amorphous phase are formed. A magnetic element comprising an alloy ribbon, an alloy wire, or an alloy thin film in which a region occupying at least 50% is mixed.
Here, the alloy ribbon, the alloy wire or the alloy thin film is made of an alloy of a single composition having a usual composition variation. Here, the length of each region is usually 1μ.
It is defined as having m or more, and does not mean a region having a small crystal grain size size level. FIG. 6 shows an example of the structure of a conventional magnetic element, and FIG. 1 shows an example of the structure of the magnetic element of the present invention.

The region in which the amorphous phase occupies at least 50% may be the 100% amorphous phase, and in normal applications, this region is often used as the 100% amorphous phase. The region in which fine nano-crystal grains having a grain size of 50 nm or less occupy at least 50% of the structure may consist essentially of the crystal phase, but it is usually used in a state in which a part thereof contains the amorphous phase. Each of the regions may exist in a layered form in the thickness direction.

The alloy constituting the magnetic element is Fe as a main component and at least one element selected from Cu and Au and at least one element selected from Ti, V, Zr, Nb, Mo, Hf, Ta and W. When the element (1) is contained as an essential component, the soft magnetic characteristics of the microcrystallized region are excellent, and a good magnetic element can be obtained. More specifically, Fe-A
-M-Si-B system (A: Cu, Au, M: Ti, V, Z
An alloy having a composition of r, Nb, Mo, Hf, Ta, W) can be mentioned. In addition to these, Cr and Al may be contained for the purpose of improving the corrosion resistance and the like, if necessary.

[0008] As an alloy constituting the magnetic element, and more specifically, the general _{formula: (Fe 1-a M a} )
_1-xyzb A _x M 'is represented by _y M _"z X _b (atomic%), at least one element is M wherein selected Co, from Ni,
A is at least one element selected from Cu and Au,
M'is at least one element selected from Ti, V, Zr, Nb, Mo, Hf, Ta and W, and M "is Cr, M
n, A1, Sn, Zn, Ag, In, white metal element, M
g, Ca, Sr, Y, at least one element selected from rare earth elements, N, 0 and S, X is B, Si, C, G
at least one element selected from e, Ga and P, and a, x, y, z and b are 0 ≦ a <0.
5, 0 ≦ x ≦ 10, 0.1 ≦ y ≦ 20, 0 ≦ z ≦ 20,
An alloy having a composition represented by a number satisfying 2 ≦ b ≦ 30 can be given. The crystals existing in the alloy having the above composition are mainly bcc.
When it is an Fe phase and contains Si, Si may form a solid solution in the bcc phase and may contain an ordered lattice. In addition, elements other than Si, such as B, A1, Ge, Zr, and Ga, may be solid-dissolved. The balance other than the crystalline phase is mainly an amorphous phase.

In particular, when the region where the amorphous phase occupies at least 50% exceeds 50% of the total volume of the alloy, the magnetic element is suitable for the magnetostrictive sensor. That is, by forming a region in which fine nano-crystal grains with a grain size of 50 nm or less occupy at least 50% of the structure in a portion to which a magnetic field is applied from the outside, and arranging an exciting coil in this portion to excite, magnetization can be easily performed can do. For example, in a position sensor or the like using magnetoelastic waves due to magnetostriction, by nanocrystallizing the region of the drive coil portion, the current flowing through the coil can be reduced or the number of turns of the coil can be reduced.

In the case of a ribbon or wire, the particle size is 50
At least 50% of the structure is composed of fine nano-grains of nm or less
The magnetic element in which the regions occupying and the regions occupying at least 50% of the amorphous phase are alternately arranged in the longitudinal direction of the strip or the longitudinal direction of the wire is easy to use as a sensor. By changing the lengths of the nano-crystal region and the amorphous region and making rough patterns of various patterns, the magnetic element for sensor used to identify articles and people can locally heat-treat one material. Can be easily obtained by. In the case of a thin film, it is possible to fabricate a magnetic element in which various patterns are two-dimensionally changed within the film surface, and integration is possible.

Another aspect of the present invention is a region in which amorphous alloy ribbons, wires, and thin films are produced and locally heated to be microcrystallized, and fine nanocrystal grains having a grain size of 50 nm or less occupy at least 50% of the structure. And a region in which the amorphous phase occupies at least 50% are formed in a macroscopically mixed alloy. As a method of local heating, a method of locally passing an electric current or a method of irradiating a laser beam is suitable because a nanocrystal region can be easily generated in various patterns.

The alloy constituting the magnetic element of the present invention is amorphous by a liquid quenching method such as a single roll method, a twin roll method, a rotating submerged spinning method, or a vapor phase quenching method such as a sputtering method, a vapor deposition method or an ion plating method. After the alloy is produced, it is locally heated to be microcrystallized, and a region in which fine nano-crystal grains having a grain size of 50 nm or less occupy at least 50% of the structure and a region in which the amorphous phase occupies at least 50% are mixed It is produced by Further, when the alloy is produced by a liquid quenching method or a gas phase quenching method, at least 50 nanocrystalline grains of the structure are directly formed by raising the temperature of a cooling roll or a substrate so that the cooling rate is partially slowed. %
The magnetic element of the present invention can be manufactured by forming a region occupying the area. However, from the viewpoint of controlling the proportion and structure of each region, it is better to locally heat the amorphous alloy and then locally heat it. Local heating heat treatment is usually 45
It is performed under the condition that the temperature of the alloy is raised to a temperature in the range of 0 ° C. to 700 ° C. and above the crystallization temperature. The heating is performed in an inert gas atmosphere such as a nitrogen gas atmosphere or an Ar gas atmosphere, or
It is performed in an oxidizing atmosphere such as the atmosphere. Further, before or after the local heating, the entire alloy may be heat-treated at a temperature equal to or lower than the crystallization temperature in order to improve the magnetic characteristics of the region where the amorphous phase occupies at least 50% or more.

An Fe-R-X type alloy may be used as an alloy forming the magnetic element. here,
It is also possible to use an alloy in which R is at least one element selected from Y and rare earth elements, and X is at least one element selected from B, N and C. If necessary, Co, Ni, Si, Ga, Ge, P, Cu, Au,
Ti, V, Zr, Nb, Mo, Hf, Ta, W, Cr,
Mn, A1, Sn, Zn, Ag, In, white metal element, M
at least 1 selected from g, Ca, Sr, O and S
It may also contain seed elements. More specifically, the general formula: F
e _100-xyz R _x X _y M _z (atomic%), wherein R is Y, at least one element selected from rare earth elements, X
Is at least one element selected from B, C, N, M is Co, Ni, Si, Ga, Ge, P, Cu, Au, T
i, V, Zr, Nb, Mo, Hf, Ta, W, Cr, M
n, A1, Sn, Zn, Ag, In, white metal element, M
at least 1 selected from g, Ca, Sr, O and S
It is a kind of element and 1 ≦ x ≦ 30, 1 ≦ y ≦ 20, 0 ≦ z
An alloy having a composition satisfying ≦ 20 can be mentioned. In this case, a compound phase is formed in the region that has become a nanocrystalline alloy, the coercive force is larger than that in the region of the amorphous alloy, and it can be used as a magnetic element that needs to be applied with a bias magnetic field. The bcc phase may exist in the region of the nanocrystalline alloy. An example of this magnetic element is a case where a bias magnetic field must be applied to a high magnetostrictive rare earth-Fe amorphous alloy. By magnetizing the nano-crystallized region, a bias magnetic field can be applied to the amorphous region, and an excellent magnetic element can be realized from one material.

Further, even in an alloy system containing no R, an Fe-B compound, an Fe-C compound or an Fe-P compound having large magnetic anisotropy is formed in the nanocrystallized region to form a region having large coercive force. The same effect can be realized. By magnetizing or demagnetizing a region having a large coercive force, a state in which a region exhibiting soft magnetism is not magnetized is created, and a signal can be detected or a signal cannot be detected.
As a result, the detection signal changes, so it can also be used as an antitheft sensor or the like. The magnetic element that has been locally heat-treated is put in a case or tube as needed to improve damage or environmental resistance, the surface is covered with resin, it is sandwiched with resin tape or paper tape, and one side is You may cover it and use it. Further, alloy ribbons may be laminated or knitted, and wires may be bundled or knitted. Further, the ribbon or the wire may be wound in a toroidal shape to be used as a magnetic core exhibiting composite characteristics, or may be used as a laminated magnetic core. Forming an insulating layer on the surface of the magnetic element,
You may perform plating etc.

After the amorphous alloy ribbon, the wire, and the thin film are produced, they are locally heated to be finely crystallized, and fine nanocrystal grains having a grain size of 50 nm or less occupy at least 50% of the structure and at least 50 amorphous phases. By forming an alloy in which the region occupying% is mixed macroscopically and forming a magnetic element from this alloy, a smaller magnetic element can be realized as compared with the case where a plurality of elements are used in combination. Furthermore, by changing the heating location, size, and temperature when locally heating, magnetic materials with different magnetic properties and dimensions can be realized with one material. Therefore, conventional magnetic materials with different materials and different dimensions must be prepared. The degree of freedom of the pattern can be increased as compared with the combination.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to Examples, but the present invention is not limited thereto. (Example 1) Width 1.5 mm and thickness 17μ by the single roll method
m Fe _bal Cu ₁ Nb ₃ Si _15.5 B ₇ amorphous alloy ribbon was prepared. The alloy strip was then cut to a length of 100 mm. Next, an electric current is applied to a part of this ribbon to locally heat it, and the fine nano-crystal grains with a grain size of 12 nm make up about 80% of the structure.
The region A occupying the area was formed, and the magnetic element of the present invention was produced.
FIG. 2 shows a schematic diagram of the structure. Area B is an amorphous phase area. Next, this element was attached to an article as an identification sensor, subjected to alternating-current excitation from the outside, and the output harmonic was detected by a detection coil. It was found that the detected waveform changes depending on the length of the local heating and the pattern, and can be sufficiently used as a magnetic element for an identification sensor. As described above, according to the present invention, the identification sensor can be configured with only one ribbon.

(Embodiment 2) Fe _bal Cu ₁ Z having a width of 1 mm and a thickness of 15 μm by a single roll method in a He gas depressurized atmosphere.
to prepare a r ₇ B ₆ amorphous alloy ribbon. The alloy strip was then cut to a length of 80 mm. Next, a heating element was brought into contact with part of this ribbon to form fine nano-crystal grains having a grain size of about 18 nm or a region C occupying about 85% of the structure, to fabricate the magnetic element of the present invention. FIG. 3 shows a schematic diagram of the structure. Area D is an amorphous phase area. Next, this element was externally excited with an alternating current, and the output coil was used to detect harmonics in the output. It was found that the detected waveform changes depending on the length and pattern of local heating and can be sufficiently used as a magnetic element for an identification sensor. As described above, according to the present invention, it is possible to implement the identification sensor with only one ribbon.

(Embodiment 3) A width of 1 mm by a single roll method,
A Fe _bal Cu ₁ Ta _2.5 Si ₁₄ B ₈ amorphous alloy ribbon having a thickness of 15 μm was produced. Next, this alloy ribbon is
Cut into mm. Next, a laser beam is irradiated on a part of the ribbon, and fine nano-crystal grains having a grain size of about 14 nm form a structure of about 85 nm.
By forming a region occupying 100%, a magnetic element of the present invention was manufactured.
As a result of X-ray diffraction, Fe ₂ B was formed in this region.
The element structure is similar to that shown in FIG. Next, this element was externally excited with an alternating current, and the output coil was used to detect harmonics in the output. Next, a direct current magnetic field was applied to this element to magnetize the crystallized portion, and similarly subjected to alternating current excitation. It has been found that it can be sufficiently used as a magnetic element for an identification sensor. As described above, according to the present invention, the identification sensor can be configured with only one ribbon.

(Example 4) A diameter of 1 was obtained by a spinning liquid spinning method.
A 00 μm Fe _bal Cu ₁ Nb _3.5 Si _14.5 B ₉ amorphous alloy wire was prepared. Next, this alloy was drawn to have a diameter of 40 μm. This alloy wire was cut into a length of 200 mm, and an electric current was locally applied to heat the alloy wire to manufacture the magnetic element of the present invention. As a result of X-ray diffraction and microstructure observation, it was confirmed that 75% of bcc crystal grains having a grain size of about 1 nm were formed in the heated portion E. The device structure is shown in FIG. Next, an exciting coil F was wound around the crystallized region of this alloy wire to be excited to generate a magnetoelastic wave, thereby constructing a position sensor. The detection coil G is arranged as shown. The results are shown in Table 1. The detection signal was larger when a part of them was nanocrystallized.

[0019]

[Table 1]

Example 5 An amorphous alloy film having the composition shown in Table 2 was prepared by the sputtering method.

[0021]

[Table 2]

Next, the surface of this film was irradiated with laser light to locally heat and crystallize. As a result of microstructure observation, it was confirmed that the crystallized portion was composed of fine crystal grains having a grain size of 50 nm or less. The device structure is shown in FIG. Next, this element was externally excited with an alternating current, and the output coil was used to detect harmonics in the output. Next, a direct current magnetic field was applied to this element to magnetize the crystallized portion, and similarly subjected to alternating current excitation. It has been found that it can be sufficiently used as a magnetic element for an identification sensor. As described above, according to the present invention, the identification sensor can be configured with only one ribbon.

[0023]

According to the present invention, it is possible to provide a magnetic element suitable for various sensors such as an anti-theft sensor, an article identification sensor, and a magnetostrictive sensor, and a method for manufacturing the same, so that the effect is remarkable.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a structure of a magnetic element of the present invention.

FIG. 2 is a diagram showing an example of a structure of a magnetic element of the present invention.

FIG. 3 is a diagram showing an example of a structure of a magnetic element of the present invention.

FIG. 4 is a diagram showing an example of a structure of a magnetic element of the present invention.

FIG. 5 is a diagram showing an example of a structure of a magnetic element of the present invention.

FIG. 6 is a diagram showing an example of a structure of a conventional magnetic element.

[Explanation of symbols]

 A area where nano-crystal grains occupy 80% of the structure B area of amorphous phase C area where nano-crystal grains occupy 85% of the structure D area of amorphous phase E area where nano-crystal grains occupy 75% of the structure F exciting coil G Detection coil

Claims (7)

[Claims] 1. An alloy ribbon, an alloy wire, or an alloy thin film in which a region where at least 50% of a structure is occupied by fine nanocrystal grains having a grain size of 50 nm or less and a region where at least 50% of an amorphous phase are mixed are mixed. A magnetic element characterized by being used. 2. An alloy ribbon forming the magnetic element,
Alloy wire or alloy thin film is mainly composed of Fe, Cu, A
at least one element selected from u and Ti, V, Z
2. The magnetic element according to claim 1, which contains at least one element selected from r, Nb, Mo, Hf, Ta, and W as an essential component. 3. The magnetic material according to claim 1, wherein the region where the amorphous phase occupies at least 50% exceeds 50% of the total volume of the alloy ribbon, the alloy wire or the alloy thin film. element. 4. A region in which fine nano-crystal grains having a grain size of 50 nm or less occupy at least 50% of a structure and a region in which an amorphous phase occupies at least 50% are alternately arranged in the ribbon longitudinal direction or the wire longitudinal direction. The magnetic element according to any one of claims 1 to 3, wherein: 5. A region where an amorphous alloy ribbon, an amorphous alloy wire or an amorphous alloy thin film is locally heated and microcrystallized, and fine nanocrystal grains having a grain size of 50 nm or less occupy at least 50% of the structure. A method of manufacturing the magnetic element, wherein a region in which an amorphous phase occupies at least 50% is mixed. 6. The method of manufacturing a magnetic element according to claim 5, wherein the local heating is performed by passing a current through the amorphous alloy ribbon, the amorphous alloy wire or the amorphous alloy thin film. 7. The method for producing a magnetic element according to claim 5, wherein the local heating is performed by irradiating the amorphous alloy ribbon, the amorphous alloy wire or the amorphous alloy thin film with laser light.