JPH0494198A - Electro-magnetic shield material - Google Patents

Abstract

PURPOSE:To make it possible to perform at least one type of electric, magnetic, and electromagnetic shield by using a material aggregation which comprises a formation body made of assembled materials and produces a printed state between the materials. CONSTITUTION:A material aggregation is a three layer-based material which comprises an outer layer material 1, a middle layer material 2, and a inner layer material. Each material which constitutes the outer layer 1 and the middle, comprises three laminated copper plates having directional and electromagnetic properties. The material for the inner layer is PB permalloy. The permalloy, which constitutes the inner layer material 3 is magnetic-annealed in a hydrogen atmosphere. After it is annealed, the uncovered surfaces of the outer layer material 1 and the middle layer material and the permalloy surface of the inner layer material 3 are copper-plated and further tin-plated thereon. Each layer material 1, 2, and 3, which has received plating treatment, forms the material aggregation so that they may constituted each component, say 4, 5, and 6. The material aggregation or the member molded to be a magnetic shield box, is baked and annealed, which finally results in one piece body.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to materials for shielding against magnetic, electrical, and electromagnetic waves.

(Prior Art) The influence of electricity, particularly static electricity, on other devices has been a problem for a long time, and measures have been taken to seal off this static electricity. On the other hand, with the recent development of electrical and electronic equipment, the number of devices that generate magnetic fields and electromagnetic waves has increased, and high-performance devices are being used in a variety of environments. It has become a big problem.

In order to achieve high shielding performance with these electromagnetic shielding technologies, it is necessary to respond differently depending on the strength and frequency of electricity, magnetism, and electromagnetism. In order to demonstrate performance, shielding is performed by combining multiple types of materials, and by taking into account the shape and direction of the materials, which makes handling the materials complicated.

In order to apply electromagnetic shielding, it is important to consider the space of equipment, buildings, etc., and also the construction method, especially the ease of construction. For example, it is necessary to handle materials such as thin plates and foils, and it is very time-consuming to attach these materials. These works are performed in addition to the work related to the equipment or building, which is the original purpose, but since the shielding material does not have mechanical strength, it is necessary to work on the main body case of the equipment, the wall of the building, etc. Work cannot be done without using shielding materials.

As mentioned in the second point, conventional electromagnetic shielding materials are complicated and require a large amount of handling, and additional shielding is required, so new means of improvement are desired.

(Problems to be Solved by the Invention) The present invention solves the problems of the prior art described above, and allows a single material to have multiple functions, has mechanical strength, and is relatively durable in its final use shape. The purpose of the present invention is to provide an electromagnetic shielding material that can be easily provided.

(Means for Solving the Problems) The gist of the present invention is as follows: (1) It is characterized by using a material aggregate that is made of a formed body made by combining materials and in which the materials are in a burned-in state. Materials for electromagnetic shielding.

(2) The electromagnetic shielding material according to item 1 above, wherein the material has a plating layer of a conductive material.

(3) Items 1 and 2 above, which are material aggregates formed by combining materials such that the materials are arranged so as to follow the flow of any one or more of electric flux, current, and magnetic flux, resulting in high electromagnetic shielding. Materials for electromagnetic shielding.

(4) The electromagnetic shielding material according to item 1, 2 or 3 above, wherein the material is a magnetic material.

(5) The material for electromagnetic shielding according to item 4, which is a magnetic material aggregate formed by combining materials such that the axis of easy magnetization of the magnetic material follows the flow of magnetic flux resulting in a high electromagnetic shield.

(6) Item 1 above, characterized in that the materials are processed and combined to form a predetermined shape for use, and then brought into a burned state. 2. The electromagnetic shielding material described in 3.4 or 5.

(7) The electromagnetic shielding material according to item 6 above, which is subjected to press processing to obtain a final shape.

(8) The preceding item 6 has a mating part for attachment at the end.
Or the electromagnetic shielding material described in 7.

It is in.

The present invention will be explained in detail below.

First, the electromagnetic shield of the present invention refers to a shield related to electricity such as static electricity, magnetism, and electromagnetic waves, and is intended to eliminate or reduce these interferences from the outside, or to prevent electricity, magnetism, and electromagnetic waves from being transmitted to the outside. It is for. The electromagnetic shield of the present invention includes not only shielding of electricity, magnetism, and electromagnetic waves all at the same time, but also shielding of one or more of them.

The material used for the electromagnetic shielding material is a conductive material or a magnetic material, and may be a dielectric material or the like as long as it can be baked as described later.

The conductive material of the present invention may be a conductive metal such as copper, aluminum, or iron, or may be an alloy of two or more types of conductive metals. The magnetic materials used in the present invention include electrical steel sheets such as silicon steel sheets, electromagnetic soft iron, common steel, iron-nickel alloys, iron-cobalt alloys, and other magnetic materials. There are no restrictions on the shapes of these conductive materials and magnetic materials, and the types and shapes of magnetic materials may not be one, but a combination of two or more types.

When used as a material assembly (including magnetic material assembly), in order to obtain high electromagnetic shielding, it is necessary to use a plate or wire of material that passes through the material along a predetermined electric flux, current, or magnetic flux flow. It is good to consider the arrangement, shape, and type. Alternatively, the magnetic easy axis of the magnetic material may be aligned along the magnetic flux flow. For example, in the case of iron, the axis of easy magnetization is the crystal orientation (100
), and this direction may be set along a predetermined magnetic flux flow.

The material assembly needs to have a low interlayer electrical resistance or a high mechanical strength by sufficiently baking the materials. The purpose of reducing the interlayer electrical resistance between materials is to reduce the electrical resistance between the materials, allowing current to flow from one material to an adjacent material, and to allow current to flow along the layers between the materials. The high mechanical strength is required to function as a material for a structure, but it may be necessary to simultaneously reduce the interlayer electrical resistance and provide high mechanical strength.

In the case of magnetic material aggregates, annealing for burning not only ensures sufficient burning between the materials, reduces interlayer electrical resistance, secures a predetermined shape, and obtains mechanical strength.
It is preferable that processing strain caused during the process is also released at the same time. This is to give the magnetic material aggregate excellent magnetization characteristics.

In order to sufficiently bake between materials in a material aggregate, reduce the interlayer electrical resistance between the materials, and increase mechanical strength, the surface of the materials must be It is effective to use a material plated with a conductive material. Using a material whose surface is plated with a conductive material can reduce the electrical resistance between the combined materials, and can also be used in cases where the plated conductive material is more likely to seize than the unplated material. can obtain higher mechanical strength annealing.

Copper, as a conductive material plated on the surface of magnetic material.
Aluminum, nickel, tin, zinc, etc. and alloys thereof can be used. The plating thickness is the thickness necessary to reduce the electrical resistance between the combined materials, promote seizure between the materials, and ensure sufficient mechanical strength of the material combination formed body. good. The type of conductive material to be plated on the surface of the material must be determined depending on the difficulty of plating and the required electrical and magnetic circuit characteristics.

When a magnetic flux is caused to flow in a direction perpendicular to the surface of a magnetic material, it is preferable to select a conductive material plated with a material with excellent magnetization properties, such as nickel, to form a magnetic material aggregate. On the other hand, when flowing magnetic flux parallel to the surface direction of a magnetic material such as a plate or wire, a material plated with a non-magnetic conductive material may be used.

If you want current to flow only in one direction, you can combine conductive and non-conductive materials to form a material aggregate. For example, a conductive plate-like material and a non-conductive plate-like material are laminated every other sheet.

If the purpose is achieved, instead of using only the plated material, a part of the plated material or a partially plated material may be used.

The material assembly made as described above is used as an electromagnetic shielding material, and is processed by baking and annealing, taking into account the shape, combination, etc. of the materials before baking, taking into consideration the final shape. In this case, the final shape will be obtained after baking annealing. The shape and type of material may not be one, but may be multiple.

In order to obtain the final shape, press working may be performed before or after annealing, or annealing may be performed in a press-formed state.

It goes without saying that if the final shape of the electromagnetic shielding material is provided with an attachment part at the end for attaching the material, its utility value will be increased. For example, when plate-shaped materials are used in a stacked manner, assembly is facilitated by interlocking the electromagnetic shielding material, in which the stacked ends are made to protrude from every other plate, with other shielding parts.

The method is not limited to the method of protruding and interlocking every other plate, but it is also possible to use every other plurality of plates, or other methods may be used as long as the plates can be interlocked with each other.

The electromagnetic shielding material produced in this way has an arbitrary shape, allows a predetermined magnetic flux flow, and has a low interlayer resistance of the material forming the electromagnetic shielding material. Furthermore, it is easy to process, and the strength between the laminated layers can be increased, so that sufficient mechanical strength can be obtained.

(Example) Fig. 1 shows an electromagnetic shielding material, and Fig. 2 shows an example of an electromagnetic shielding topo for CRTs that uses the electromagnetic shielding material to shield against external electromagnetism. show.

That is, FIG. 2 consists of a central molded member 4 forming an electromagnetic shield box, and left and right side molded members 5.6, and each molded member 4, 5.6, as shown in FIG. It is a material assembly composed of three layers of shielding materials, namely an outer layer material 1, an intermediate layer material 2, and an inner layer material 3. The material for the outer layer 1 and the intermediate layer 2 is composed of three grain-oriented electrical steel plates with a thickness of 0.2 km laminated, and the material for the inner layer 3 is made of PB permalloy, which is a 45% Ni alloy, and has a thickness of 1 am. (In Fig. 1, (a) is a material assembly 4' showing a part of the central molded member 4, and (b) is a material assembly showing a part of the right (left) side molded member 5 (6). Body 5' is shown.

These electromagnetic steel sheets and permalloy were cut and press-bent into the shapes of the central molded member 4 and right and left side molded members 5 and 6 that form the seal box shown in FIG. The outer layer material 1 and the intermediate layer material 2 are formed by laminating the outer layer material 1 and the intermediate layer material 2, respectively. Permalloy, which becomes the unidirectional layer material 3, is heated to 1100℃ in a hydrogen atmosphere with a dew point of -40℃.
Magnetic annealing is performed for ×2 hours. Thereafter, the surfaces of the outer layer material 1 and the intermediate layer material 2 without coatings, as well as the permalloy surface of the outer layer material 3, are plated with copper to a thickness of 1 uJa and further tin plated thereon.

Each layer material plated in this way 1. 2. 3 is
A material assembly is formed to form each of the constituent members 4, 5, and 6 shown in FIG.

At this time, as shown in FIG. 1, both ends of the intermediate layer material 2 in the material assembly 4' are provided with protrusions 7 that protrude from both end surfaces of the outer layer material 1 and the inner layer material 3, and the right side material At the joint part of the assembly 5' with another material assembly (center molded material) 4', the end of the intermediate layer material 2 is provided with a groove 8 recessed from the outer end surface of the inner layer materials 2 and 3. (Although not shown, the left material aggregate is also the same) and the protruding portion 7 is
The outer layer material 1 and the intermediate layer material 2 are arranged so that the rolling direction of the electromagnetic steel sheets constituting them is in the direction of the arrow 1' in FIG. As shown in 2', the materials of each layer are the same, but the materials of each layer are arranged in a perpendicular direction, so that the axes of easy magnetization are orthogonal between the layers 1 and 2.

Each material assembly member having the above-mentioned treatment and structure, that is, a member molded to form the magnetic shield box shown in Figure 2, is baked and annealed at 900°C for 2 hours, and finally these are integrated into one piece. Be what you become.

In this way, the CRT electromagnetic shielding box made is made of electromagnetic steel for the outside and permalloy, which has high magnetic permeability, is used for the inside, so it is highly effective in magnetic shielding against geomagnetism and other magnetic fields, and is plated with copper. Since it is made of conductive materials, it is also effective as a shield against electromagnetic waves and as a shield against static electricity.

(Effects of the Invention) The electromagnetic shielding material of the present invention is made by combining multiple types of materials, so it can shield one or more types of electricity, magnetism, and electromagnetic waves, and can shield electric fields,
The magnitude and frequency of the magnetic field can also be used in one or more ranges.

Therefore, conventionally, when constructing a shield, multiple works were required, but as described above, it is possible to satisfy multiple requirements with one electromagnetic shielding material, so the number of works is reduced. It's done.

In addition, since the electromagnetic shielding material of the present invention is made by combining various materials, materials with extremely excellent properties can be easily formed into any final shape by laminating or bundling, and can be easily formed into any desired final shape. It provides excellent properties that are difficult to obtain in bulk.

As the magnetic material for electromagnetic shielding materials, silicon steel sheets, which have extremely excellent magnetization properties, can be used, and since they are finally produced through an annealing process, no processing distortion remains and they provide good magnetic properties. , the magnetic flux density of the material used can be higher than usual. Furthermore, it is possible to design the axis of easy magnetization of the magnetic material used to follow a predetermined magnetic flux flow, making it easy to obtain the desired magnetic flux density and magnetic flux distribution between the magnetic poles.

If the material is an electromagnetic shielding material that has a plating layer of conductive material, electric current will flow between the materials, making it possible or efficient to shield electricity, and if it is an alternating current, eddy currents due to changes in magnetic flux will flow between the materials. This also makes it possible to improve electromagnetic shielding.

The arrangement of materials may be combined to follow the flow of one or more of electric flux, current, and magnetic flux that provides high electromagnetic shielding, or if the material is a magnetic material, the magnetization of the magnetic material may be If the easy axis is formed by combining materials so as to follow the flow of magnetic flux that provides high electromagnetic shielding, not only will the electromagnetic shielding be high, but the device can also be made smaller and lighter.

After combining the materials by shearing, pressing, etc. to obtain a predetermined shape for use, the desired shape can be easily formed by combining the materials into a sewn state.

If the electromagnetic shielding material has a mating part for attachment at the end, there is no need to perform machining of the attachment part again, which is very convenient.

In this way, as materials for electromagnetic shielding, electrical,
It is magnetically ideal. Furthermore, by combining magnetic materials such as plates, wires, and grains into a shape that suits the purpose, molding it, and baking it, it is possible to obtain a small yoke of any shape. This means that a material for electromagnetic shielding can be obtained at low cost. Furthermore, the mechanical strength required for the electromagnetic shielding material can be obtained by considering the seizure strength.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the electromagnetic shielding material (material aggregate) of the present invention, and Fig. 2 is a perspective view of the electromagnetic shielding material (material aggregate) of the present invention.
An electromagnetic shielding box for RT is shown. 1: Outer layer material 3: Inner layer material 5.6: Left and right side molded members 7: Protrusion 8. Concave grooves 4', 5': Material aggregate 2: Intermediate layer material 4: Central molded member Fig. 1

Claims (8)

[Claims] (1) Consists of a formed body made by combining materials,
An electromagnetic shielding material characterized by using a material aggregate in which the materials are in a burned-in state. (2) The electromagnetic shielding material according to claim 1, wherein the material has a plating layer of a conductive material. (3) Claim 1 which is a material assembly formed by combining materials arranged so as to follow the flow of any one or more of electric flux, current, and magnetic flux that provides high electromagnetic shielding properties.
and the electromagnetic shielding material according to 2. (4) The electromagnetic shielding material according to claim 1, 2 or 3, wherein the material is a magnetic material. (5) The electromagnetic shielding material according to claim 4, which is a magnetic material aggregate formed by combining materials such that the axis of easy magnetization of the magnetic material follows a magnetic flux flow that provides high electromagnetic shielding properties. (6) The electromagnetic shielding material according to claim 1, 2, 3, 4, or 5, characterized in that the materials are processed and combined so as to have a predetermined shape for use, and then brought into a baked-in state. (7) The electromagnetic shielding material according to claim 6, which is subjected to press processing to obtain a final shape. (8) The electromagnetic shielding material according to claim 6 or 7, which has a mating part for attachment at the end.