JPH06120020A - Composite material and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a manufacturing method for composite material having desired characteristics independent of matrix phase material. CONSTITUTION:This composite material is a complex formed by a plurality of particles of three-phase structure consisting of a first glanular material, the surface of which is coated by the second material, and the surface of the second material is coated with the third material. A second material is the oxyphilic substance such as Al, Si, Ti, Mg, Ca and the like, or an alloy containing at least one or more kinds of elements selected from the above- mentioned oxyphilic substance, and a third material is the high electric resistance substance which is obtained by oxidation or nitrification. According to this structure, the composite material can be obtained by isolating each of the first material using a small quantity of insulator, and also as the first material is not directly oxidized or nitrified, the deterioration in characteristics due to the compositional deviation of the matrix phase material can be eliminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention requires a magnetic recording head such as a transformer, a noise filter, an electronic component using a magnetic circuit, a magnetic material used in an electronic device, a high thermal conductivity and a high electric resistance. The present invention relates to a composite material for providing a circuit wiring board or the like.

[0002]

2. Description of the Related Art Conventionally, for electronic parts and electronic equipment, for example, a composite material having a filler such as glass, ceramics or resin as a main component material of the composite material (hereinafter referred to as a matrix material) has been used. It was For example, in a composite material in which a magnetic metal is used as a matrix material and separated by an insulator, it is used as a material for magnetic cores and heads that reduce eddy current loss in the high frequency region. For example, a metal is used as a matrix material and separated by an insulator. The composite material is used as a material such as a circuit wiring board that requires high thermal conductivity and high electrical resistance.

[0003]

However, in the conventional metal / insulator composite material, in order to obtain sufficient insulation, the amount of the insulator continuous phase covering the matrix material must be increased, and thus The phase material had a large gap and the insulator layer had a large thickness. In such a configuration, for example, when the above-mentioned magnetic composite material is used for the magnetic core, the high magnetic flux density of the magnetic metal is thinned by the insulating material, and the magnetic permeability of the insulating material greatly increases. Fall to.

Therefore, the surface of the mother phase material is directly oxidized or nitrided to form a very thin insulating layer, which is then filled or molded at a high density and then sintered at high temperature and high pressure to form the mother phase material. Attempts have also been made to reduce the distance between the two so as not to impair the characteristics of the matrix material. However, when the matrix material does not contain a metal component capable of forming an insulator by oxidation or nitridation, or when it contains a very small amount, for example, Fe having a high saturation magnetic flux density is used as a main component. In the case of metal or the like, there is a problem that an insulating film cannot be formed, and there is a problem that desired characteristics cannot be obtained.

An object of the present invention is to provide a composite material having desired properties independent of a matrix material and a method for producing the same.

[0006]

According to the present invention, one surface of a second substance has either the first substance or voids, and the opposite surface has either the third substance or voids, which are adjacent to each other. The conventional problem is solved by a composite material in which either the third substance or the void is interposed between the first substances, and the third substance or the void is interposed between the adjacent second substances.

This composite material can be manufactured by oxidizing or nitriding the second substance formed on the surface of the first substance to sinter or shape the substance forming the third substance.

[0008]

[Function] The composite material of the present invention comprises the first substance, the second substance and the third substance.
Contains substances. The second substance is a thin film containing an oxyphilic element or a nitrophilic element formed on the surface of one substance, and the third substance is an oxide or a nitride of the second substance. Therefore, the first
The substance is separated from other first substances by a third substance or a void having different characteristics from the first substance such as a high electric resistance material. Therefore, as in the conventional case, even if the element forming the oxide or nitride is not contained in the constituent elements of the first substance, or even if it is contained in a very small amount, the parent contained in the second substance By the selective oxidation of the oxygen element or the selective nitridation of the nitrogen-philic element, a dense and uniform protective oxide film or nitride film is formed on the surface of the second material.

[0009]

EXAMPLES The composite material of the present invention has, in addition to the main characteristics of the composite, such as magnetic characteristics or heat conduction characteristics, high electrical resistance,
Since the material has secondary characteristics such as heat resistance, corrosion resistance, and abrasion resistance, it is desirable that the characteristics of the first substance and the third substance are partially different. The third substance is obtained by oxidizing or nitriding the second substance provided on the surface of the first substance. Therefore the second
The substance includes an oxyphilic substance or a nitrophilic substance that exhibits high electrical resistance by oxidation or nitridation.

For example, when the composite material of the present invention is used as a composite magnetic material, any of the first substance, the second substance and the third substance may be a magnetic material, but a composite substance having a high saturation magnetic flux density is particularly preferable. When used as a magnetic material, the second substance contains an oxygen-philic element or a nitrogen-philic element, and the third substance contains an oxide or a nitride, and is generally either an oxygen-philic element or a nitrogen-containing element. Since the saturation magnetic flux density (Bs) is reduced when a large amount of is contained, it is desirable that at least the first substance is a magnetic substance.

The first substance applied to the present invention is:
Although not particularly limited, for example, Fe, Co, Fe-Al, F
e-Si, Fe-Si-Al, Fe-Si-Al-N
i, Fe-Ni, Fe-Ni-Mo, Co-Si, Co
A magnetic alloy such as -Si-B having a particularly high Bs is desirable. The second substance in this case is not particularly limited, but at least one element having a low oxide formation free energy or a low nitride formation free energy such as Al, Si, Ti, Mg, and Ca is used. It is desirable to include it.

First used in the composite magnetic material of the present invention
When the shape of the substance is directional, for example, in the case of a uniaxial shape such as a thin film, when the application direction of the alternating magnetic field is parallel to the film, the eddy current induced in the first substance Is suppressed by the third substance having a high electric resistance and the void, but when the application direction of the alternating magnetic field is perpendicular to the film, the induced current is determined only by the resistance of the first substance, and the eddy current cannot be suppressed. Therefore, the shape of the first substance is preferably granular so that the eddy current can be suppressed by applying a magnetic field in any direction.

When the composite material of the present invention is used as a composite high thermal conductivity and high electric resistance material, the first substance applied is, for example, a high thermal conductive metal such as Cu or Ag, or the second material in this case. As the substance, Al, Si, Ti, Mg,
It is preferable that at least one element having a low oxide formation free energy such as Ca or nitride energy has at least one element.

The composite material of the present invention comprises a forming step of forming a second material on a first material, a processing step of oxidizing or specializing the second material to form a third material, and a sintering or molding step. According to the manufacturing method including. A mechanical alloying method, a plating method, or a vapor phase method is used as the step of forming the second substance.

When the mechanical alloying method is used in the step of forming the second substance, the mechanical alloying method can partially alloy the metal interface coated with the matrix material by mechanical energy, and the adhesion force can be increased. Is especially effective for substances that do not provide sufficient. When the mechanical alloying method is used, the second substance is not particularly limited, and particularly when the melting point of the metal to be coated is high such as Si, which is not suitable for vapor deposition, or the metal to be coated. In addition, it is effective when there is no suitable electrolytic solution necessary for plating, such as Ti, which is preferable.

When the vapor phase method is used in the step of forming the second substance, the coating metal is more easily applied more densely than the mechanical alloying method, and the vapor phase method is a thin film of, for example, 10 nm or less as compared with other forming methods. Is preferable because it can be stably formed.

Further, it is preferable to use the plating method in the step of forming the second substance because it is most excellent in production efficiency as compared with other forming methods.

The condition of the treatment step applied to the method for producing a composite of the present invention is that the first substance formed with the second substance is 300 to 10 in an atmosphere containing at least oxygen or nitrogen.
Generally, the third substance is formed by heating to about 00 ° C. for about 1 minute to 10 hours. The heating conditions depend on the supply amount of oxygen or nitrogen in the atmosphere, the heating temperature or the heating time, and the optimum conditions are selected as appropriate.

After the third substance is formed through the treatment step, it is heated to, for example, about 300 to 1000 ° C. and sintered, or molded under a pressure of, for example, about 1 kg / cm 2 to 10 t / cm 2, to obtain the composite material of the present invention. obtain. Needless to say, the sintering or molding step and the processing step may be performed simultaneously.

The composite material of the present invention thus obtained is
It is particularly effective when used as a magnetic material or a material having high thermal conductivity and high electric resistance, and further, the obtained composite material has many properties such as heat resistance, corrosion resistance and abrasion resistance as well as high electric resistance. It also has the effect of being excellent in additional characteristics.

Example 1 The following experiment was conducted for the purpose of obtaining a magnetic material having a high saturation magnetic flux density and a high electric resistance.

The composition of the first substance is Fe-95 wt.
%, Si-5 wt.% Fe-Si alloy spherical powder (average particle size of about 20 μm) was used, and RF target was used on the first material to form a Si target at a substrate temperature of 300 ° C. and 8 mTorrAr gas. Sputtering was performed in an atmosphere to form a Si coating layer (second material) on the surface. During the sputtering, the spherical powder was vibrated every 30 seconds to uniformly form the coating layer. Then 700 ℃, 500p
pm of O ₂ + residual Ar atmosphere and then thermally treated oxide film (third
Substance) to obtain powder A.

For comparison, the spherical powder was heat-treated in the conventional manner at 700 ° C. in an atmosphere of a mixed gas of O ₂ and Ar at 500 ppm to form an oxide film.
And, using a RF magnetron sputter on the spherical powder, a Si target was placed at a substrate temperature of 300 ° C. and Ar and O ₂
Powder C having an insulating layer directly formed on the surface thereof was prepared by sputtering in a mixed gas atmosphere.

The film thickness of Si coating and the film thickness and composition of each oxide film were evaluated by Auger spectroscopic analysis / depth profile by Ar sputtering. As a result, the Si coating layer by sputtering had an average thickness of 30 nm, only Si and O were detected in the oxide layer of powder A, and the oxide film thickness was 25 nm. Further, trace amounts of Si, Fe and O were detected in the oxide layer of the powder B, and the oxide film thickness was 2
9nm, Si and O and a trace amount of F from the oxide layer of spherical powder C
e was detected, and the oxide film thickness was 31 nm.

These powders are sintered to a relative density of about 98%
A high density composite of The specific electric resistance ρ, the saturation magnetic flux density Bs, the magnetic permeability μ at 100 Hz and 1 Mz, and the measured magnetic flux density 50 mT and the loss PL at 100 KHz of the obtained magnetic material are shown in (Table 1).

[0026]

[Table 1]

As described above, in the case of the powder B obtained by directly heat-treating the matrix material containing Fe as a main component, the amount of Fe oxidation is Si.
Since the amount of oxidation is larger than that of Fe, the electric resistance is low
An oxide is generated and an insulating layer cannot be formed. It is also considered that the insulator of powder C grown from the metal layer coated by sputtering or the like covers the surface of the matrix material more densely than the insulator formed directly on the surface of the powder by sputtering.

(Example 2) The composition of the first substance is Fe-8.
5 wt.%, Si-9.5 wt.%, Al-5.5 wt.
% (Bs = 1.1 [T]), Fe-86 wt.%, S
i-10.5 wt.%, Al-3.5 wt.% (Bs =
1.2 [T]), Fe-89 wt.%, Si-9 wt.
%, Al-2 wt.% (Bs = 1.4 [T]), Fe-
91 wt.%, Si-7 wt.%, Al-2 wt.% (B
s = 1.6 [T]), Fe-94 wt.%, Si-3w
%, Al-3 wt.% (Bs = 1.8 [T]), Fe
-97 wt.%, Si-2 wt.%, Al-1 wt.%
(Bs = 2.0 [T]), above 5 types of Fe-Si-A
After forming an Al coating layer (second substance) on the surface of a spherical powder of an 1-alloy (average particle diameter of about 20 μm) by a barrel plating method, heat treatment is performed in air at 500 ° C. to form an oxide or nitride film (first substance). 3 substances) were formed.

For comparison, the above-mentioned five kinds of spherical powders were heat-treated in the air at 500 ° C. to 800 ° C. according to the conventional method to form an oxide or nitride film.

The coating thickness and the oxidation or nitridation thickness and composition by barrel plating were evaluated by Auger spectroscopic analysis / depth profile by Ar sputtering and weight increase during heat treatment. Also has an average thickness of 50 nm, and only Al and O and a trace amount of N are detected in the oxidized or nitrided layer, and the film thickness is 32 to 35 n.
It was m. The composition of the oxide or nitride film of each powder obtained by directly heat treating the spherical powder in air is such that Fe, Al,
O and a very small amount of Si and N were detected, and the proportion of Al decreased as the composition of the saturation magnetic flux density increased, and Fe and O tended to be the main compositions. Their film thickness is 33-35n
It was m.

Each powder was sintered to a relative density of about 98
% High density composite was made. The electric resistance ρ and the magnetic permeability μ at 1 MHz of the obtained magnetic material are shown in (Table 2).

[0032]

[Table 2]

As described above, the magnetic material of the present invention exhibits a stable high resistance value and a high magnetic permeability at high frequencies regardless of the composition of the matrix material. On the other hand, in the conventional method, a high resistance value can be obtained in a composition having a low Bs, but as the Bs increases, the resistance value also decreases, and the rate at high frequencies also decreases.

Example 3 Spherical powder of Fe (average particle diameter of about 20 μm) as the first substance, and Al as the second substance
Fine particles (average particle diameter 0.1 μm) together with SUS spheres in Ar
These were placed in an atmosphere and rotated at a speed of 1800 rpm to form an Al coating layer on the surface of the spherical powder. After that, heat treatment was performed in air at 500 ° C. to form an insulating film (third substance). The film thickness of the coating and the film thickness and composition of the insulating film were evaluated by Auger spectroscopy / depth profile by Ar sputtering and weight increase during heat treatment. As a result, the Al coating layer has an average thickness of 100 nm.
Further, Fe and Al were detected near the boundary between the matrix material and the coating layer. Al and O and trace amounts of Fe and N are detected in the insulating layer, and the film thickness is 60n on average.
It was m. After heat treatment, molding was performed to produce a high density composite having a relative density of about 98%. The electric resistance ρ of the obtained magnetic material composite material is 10 ⁶ to 10 ⁸ [Ωcm] and the saturation magnetic flux density is 1.9.
It was [T].

Example 4 The following experiment was conducted for the purpose of obtaining a composite material having high thermal conductivity and high electric resistance.

Cu spherical powder (average particle diameter of about 20 μm) was used as the first substance, and Al was vapor-deposited on the first substance under a pressure of 6 × 10 ⁻⁷ Torr. The vapor deposition source was divided into 12 pieces, and each time the vapor deposition from one vapor deposition source was completed, the spherical powder was vibrated to uniformly form a coating layer. Then 70
Heat treatment was performed at 0 ° C. in an atmosphere of O ₂ + remaining Ar of 500 ppm to form an oxide film to obtain powder a.

Also, for comparison, the Cu
Powder b obtained by heat-treating spherical powder in an atmosphere of a mixed gas of O ₂ and Ar at 500 ° C. and 500 ppm to form an oxide film.
Prepared.

The respective oxide film thicknesses estimated from the increase in oxidized weight were all about 30 nm. These powders were sintered to produce a high density composite having a relative density of about 99%. The specific electric resistance ρ of the obtained composite material is 1 for the composite material of powder a.
0 ⁶ to 10 ⁸ [Ωcm], a composite material of powder b 10 ^-1 to 10
It was ² [Ωcm].

The inventors examined the second substance, the third substance and the like having many compositions in addition to the examples shown above. As the second substance, A shown in the above examples was used.
A magnetic material having a high electric resistance was obtained by heat-treating, and then densely filling, molding, and sintering those containing at least one kind of Ti, Ca, and Mg in addition to 1, 1 and Si. In addition, although the oxides of Al and Si are mainly shown as the third substance in the above-mentioned embodiment, the second substance containing at least one or more of Al, Si, Ca, and Mg is used as nitrogen. A magnetic material composite material having a high electric resistance, or a composite material having a high thermal conductivity and a high electric resistance is also obtained by filling, molding or sintering at high density after heat treatment in an atmosphere.

[0040]

According to the present invention, one surface of the second substance has either the first substance or voids, and the opposite surface has either the third substance or voids. It is a composite material in which either the third substance or the void is interposed between the two adjacent substances and the third substance or the void is interposed between the adjacent second substances.

Therefore, there is an effect of obtaining a composite material in which the first substance is isolated by substances having different properties regardless of the first substance,
Further, the composite material of the present invention can maintain the characteristics of the main composition material because the volume ratio of the substance that isolates the main composition material in the composite material can be made very small.

Further, in the method for producing a composite material of the present invention, the high electric resistance layer is formed by oxidizing or nitriding the oxygen-philic or nitrogen-philic substance formed on the surface of the main composition material. Compared to the case of directly oxidizing or nitriding the composition material, there is no compositional deviation of the main compositional material, deterioration of characteristics due to compositional deviation of the main compositional material can be eliminated, and furthermore, the composite material of the present invention can be easily manufactured. There is also a remarkable effect.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koichi Kugimiya 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. A first substance which is adjacent to one of the first substance or a void on one surface of a second substance, and a third substance or a void which is on the face opposite to the face. A composite material in which either the third substance or a void is interposed between the two, and the third substance or a void is interposed between the adjacent second substances. 2. The second substance has a content ratio of either an oxygen-philic element or a nitrogen-philic element, or an oxygen-containing element or a nitrogen-containing element is higher than that of the first substance, and The composite material according to claim 1, wherein the substance comprises an oxide of an oxygen-philic element or a nitride of a nitrogen-containing element of the second substance. 3. The composite material according to claim 1, wherein at least the first substance is a magnetic substance. 4. The composite material according to claim 1, wherein the first substance is granular. 5. A forming step of forming a second substance on the surface of the first substance, a treatment step of nitriding or oxidizing the second substance after the forming step, and a sintering or molding under high pressure after the treatment step. A method of manufacturing a composite material including a step. 6. The method for producing a composite material according to claim 6, wherein the forming step is a mechanical alloying method. 7. The method for producing a composite material according to claim 6, wherein the forming step is a plating method. 8. The method for producing a composite material according to claim 5, wherein the forming step is a vapor phase method.