JP2004253787A - Complex soft magnetic sintered material with high strength, high magnetic flux density, and high resistance, and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a complex soft magnetic sintered material with a high strength, a high magnetic flux density, and a high resistance. <P>SOLUTION: In the method of manufacturing the complex soft magnetic sintered material, a coating of a surface ZnO layer of soft magnetic sintered metal powder is applied to prepare zinc oxide coated soft magnetic metal powder, glass powder is added to and mixed with the zinc oxide coated soft magnetic metal powder to prepare mixed powder, the mixed powder is compacted and molded, and then, the mixed powder is sintered in the air or in a nonoxidative atmosphere at 300 to 1000°C. Further, the soft magnetic sintered compact is composed of a soft magnetic metal particle phase 1 obtained by the manufacturing method and a grain boundary phase 4 surrounding the soft magnetic metal particle phase 1. The soft magnetic sintered compact has a constitution in which the grain boundary phase 4 is composed of a ZnO phase 3 having a hexagonal structure, a mixed oxide phase 2 made of Fe and Zn with a cubic structure, and a glass phase 5. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance used for manufacturing motors, actuators, magnetic sensors, and the like, and a method for manufacturing the same.

Generally, iron powder, Fe-Al based iron-based soft magnetic alloy powder, Fe-Ni based iron-based soft magnetic alloy powder, Fe-Cr based iron-based soft magnetic alloy powder, Fe-Cr based iron-based soft magnetic alloy powder are used for magnetic cores of motors, actuators, magnetic sensors, and the like. A soft magnetic sintered material obtained by sintering a Si-based iron-based soft magnetic alloy powder or an Fe-Si-Al-based iron-based soft magnetic alloy powder (hereinafter, these are collectively referred to as soft magnetic metal powders); It is known that A soft magnetic sintered material obtained by sintering the soft magnetic metal powder or the like has a high magnetic flux density but a low specific resistance, and thus has poor high frequency characteristics. Therefore, a powder magnetic material in which a soft magnetic sintered material is combined with water glass or low-melting glass in order to increase specific resistance and improve high-frequency characteristics has been proposed (see Patent Document 1 or 2).
JP-A-5-258934 JP-A-63-158810

  However, a composite soft magnetic sintered material in which the soft magnetic metal powder is bonded with water glass or low melting point glass has a poor adhesion between the soft magnetic metal powder and water glass or low melting point glass. In order to secure strength by combining with water glass or low melting glass, it must be mixed with a large amount of water glass or low melting glass to the extent that soft magnetic metal powder is dispersed in water glass or low melting glass. In this way, the soft magnetic material obtained by using a large amount of water glass or low-melting glass has a large specific resistance, but its magnetic flux density is extremely low, and various electronic components such as motors, actuators, magnetic cores of magnetic sensors, etc. It cannot be used as a component material.

Therefore, the present inventors have conducted research to obtain a soft magnetic sintered material having both high strength, high magnetic flux density and high resistance.
(A) When stirring a mixed powder obtained by adding 0.02 to 10% by mass (preferably 0.1 to 5% by mass) of Zn powder to a soft magnetic metal powder, Zn is vaporized into Zn vapor, On the surface of the soft magnetic metal powder, a Zn layer, a Zn—Fe layer, or a composite layer (hereinafter, referred to as a Zn alloy layer) composed of a Zn layer and a Zn—Fe layer is formed. When the powder is heated in an oxidizing atmosphere such as carbon dioxide gas, a zinc oxide-coated soft magnetic metal powder having a zinc oxide layer formed on the surface of the soft magnetic metal powder is generated, and a small amount of glass is added to the zinc oxide-coated soft magnetic metal powder. Powder: A mixed powder obtained by adding and mixing 0.05 to 10% by mass is compacted, molded, and then sintered at a temperature of 300 to 1000 ° C., where the zinc oxide layer and glass have excellent adhesion. Has high strength and Composite soft magnetic sintered material is obtained having a resistance, further the composite soft magnetic sintered material is superior in magnetic flux density,
(B) The obtained soft magnetic sintered material having both high strength, high magnetic flux density and high resistance comprises a soft magnetic metal particle phase and a grain boundary phase surrounding the soft magnetic metal particle phase. The phase is composed of a ZnO-type phase having a hexagonal structure, a mixed oxide phase of Fe and Zn having a cubic structure, and a glass phase. Most of the mixed oxide phase of Fe and Zn having the cubic structure is dispersed in contact with the ZnO type phase, and the glass phase is Fe having the cubic structure. Having a structure interposed and dispersed between mixed oxide phases of Zn and
(C) The ZnO-type phase having a hexagonal structure and the mixed oxide phase of Fe and Zn having a cubic structure have an average particle diameter in a range of 1 to 500 nm.
(D) The soft magnetic metal powder includes iron powder, Fe-Al-based iron-based soft magnetic alloy powder, Fe-Ni-based iron-based soft magnetic alloy powder, Fe-Cr-based iron-based soft magnetic alloy powder, Fe-Si- Any of the Al-based iron-based soft magnetic alloy powder and the Fe-Si-based iron-based soft magnetic alloy powder can be used, and the composite soft magnetic sintered material produced using these soft magnetic metal powders The soft magnetic metal particle phase is iron, Fe-Al-based soft magnetic alloy, Fe-Ni-based soft magnetic alloy, Fe-Cr-based soft magnetic alloy, Fe-Si-Al-based soft magnetic alloy Research results such as the fact that it is composed of any one of the particle phases of Fe-Si based iron-based soft magnetic alloys were obtained.

The present invention has been made based on such research results,
(1) A soft magnetic metal particle phase and a grain boundary phase surrounding the soft magnetic metal particle phase, wherein the grain boundary phase is a ZnO type phase having a hexagonal structure, and a mixed oxidation of Fe and Zn having a cubic structure. The ZnO-type phase having a hexagonal structure is dispersed in contact with the soft magnetic metal particle phase, and the mixed oxide phase of Fe and Zn having the cubic structure is the ZnO-type phase. A high-density, high-strength, and high-flux-density structure having a structure in which the glass phase is dispersed in contact with the mixed oxide phase of Fe and Zn having the cubic structure. A composite soft magnetic sintered material having
(2) Each of the ZnO-type phase having a hexagonal structure and the mixed oxide phase of Fe and Zn having a cubic structure has a structure composed of a fine particle phase having an average particle diameter of 1 to 500 nm. A composite soft magnetic sintered material having high density, high strength and high magnetic flux density according to the description.
(3) The soft magnetic metal particle phase is iron, Fe-Al-based iron-based soft magnetic alloy, Fe-Ni-based iron-based soft magnetic alloy, Fe-Cr-based iron-based soft magnetic alloy, Fe-Si-Al-based iron The composite soft magnetic sinter having high density, high strength and high magnetic flux density according to the above (1) or (2), which is a particle phase of any one of the base soft magnetic alloy and the Fe-Si based iron based soft magnetic alloy. Timber,
(4) A zinc oxide-coated soft magnetic metal powder having a zinc oxide layer formed on the surface of the soft magnetic metal powder is produced, and a glass powder is added to the zinc oxide-coated soft magnetic metal powder and mixed, and the mixed powder is compacted and molded. After that, a method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance, which is sintered at a temperature of 300 to 1000 ° C.

The method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance according to the present invention will be described more specifically.
The soft magnetic metal powder used in the method for producing a composite soft magnetic sintered material having a high strength, a high magnetic flux density and a high resistance according to the present invention is an iron powder, a Fe-Al based iron-based soft magnetic material generally known in the art. Alloy powder, Fe-Ni-based iron-based soft magnetic alloy powder, Fe-Cr-based iron-based soft magnetic alloy powder, Fe-Si-Al-based iron-based soft magnetic alloy powder, Fe-Si-based iron-based soft magnetic alloy powder, etc. Yes, and more specifically,
Iron powder is pure iron powder,
The Fe-Al-based iron-based soft magnetic alloy powder contains Al: 0.1 to 20, and the balance is Fe-Al-based iron-based soft magnetic alloy powder composed of Fe and unavoidable impurities (for example, composed of Fe-15% Al). Alpalm powder having the composition)
The Fe-Ni-based iron-based soft magnetic alloy powder contains Ni: 35 to 85%, and if necessary, Mo: 5% or less, Cu: 5% or less, Cr: 2% or less, Mn: 0.5% or less. A nickel-based soft magnetic alloy powder (e.g., Fe-49% Ni powder) containing at least one of the following, and the balance being Fe and unavoidable impurities;
The Fe-Cr-based iron-based soft magnetic alloy powder contains 1 to 20% of Cr, and optionally contains one or two of Al: 5% or less and Ni: 5% or less, with the balance being the balance. Fe-Cr based iron-based soft magnetic alloy powder comprising Fe and unavoidable impurities,
The Fe-Si-Al-based iron-based soft magnetic alloy powder contains 0.1 to 10% of Si and 0.1 to 20 of Al, and the balance is Fe-Si-Al-based iron-based soft magnetic alloy composed of Fe and inevitable impurities. Magnetic alloy powder (the above,% indicates mass%)
The Fe-Si-based iron-based soft magnetic alloy powder is preferably an Fe-Si-based iron-based soft magnetic alloy powder containing 0.1 to 10% of Si and the balance being Fe and unavoidable impurities. However, the present invention is not limited to this.

Therefore, the present invention
(5) After preparing a zinc oxide-coated iron powder having a zinc oxide layer formed on the surface of the iron powder, adding and mixing a glass powder to the zinc oxide-coated iron powder, compacting and molding the mixed powder. A method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance, which is sintered at a temperature of 300 to 1000 ° C.
(6) A zinc oxide-coated Fe-Al-based iron-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of the Fe-Al-based iron-based soft-magnetic alloy powder is produced, and the zinc oxide-coated Fe-Al-based iron-based soft magnetic alloy powder is prepared. A mixed soft magnetic powder having high strength, high magnetic flux density and high resistance is sintered at a temperature of 300 to 1000 ° C. after the mixed powder obtained by adding and mixing the glass powder to the magnetic alloy powder is molded. Manufacturing method of binder,
(7) A zinc oxide-coated Fe-Ni-based iron-based soft magnetic alloy powder in which a zinc oxide layer is formed on the surface of the Fe-Ni-based iron-based soft-magnetic alloy powder is produced. A mixed soft magnetic powder having high strength, high magnetic flux density and high resistance is sintered at a temperature of 300 to 1000 ° C. after the mixed powder obtained by adding and mixing the glass powder to the magnetic alloy powder is molded. Manufacturing method of binder,
(8) A zinc oxide-coated Fe-Cr-based iron-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of the Fe-Cr-based iron-based soft-magnetic alloy powder is produced. A mixed soft magnetic powder having high strength, high magnetic flux density and high resistance is sintered at a temperature of 300 to 1000 ° C. after the mixed powder obtained by adding and mixing the glass powder to the magnetic alloy powder is molded. Manufacturing method of binder,
(9) A zinc oxide-coated Fe-Si-Al-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of the Fe-Si-Al-based iron-based soft magnetic alloy powder is prepared. -A high strength, high magnetic flux density, and high resistance in which a mixed powder obtained by adding and mixing glass powder to Al-based iron-based soft magnetic alloy powder is compacted and molded, and then sintered at a temperature of 300 to 1000 ° C. A method for producing a composite soft magnetic sintered material having
(10) A zinc oxide-coated Fe-Si-based iron-based soft magnetic alloy powder in which a zinc oxide layer is formed on the surface of the Fe-Si-based iron-based soft-magnetic alloy powder is produced. A mixed soft magnetic powder having high strength, high magnetic flux density and high resistance is sintered at a temperature of 300 to 1000 ° C. after the mixed powder obtained by adding and mixing the glass powder to the magnetic alloy powder is molded. Manufacturing method of binder,
(11) The method according to (4), (5), (6), (7), (8), (9) or (10), wherein the amount of the glass powder added is 0.05 to 10% by mass. A method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance.

The structure of the composite soft magnetic material having high density, high strength and high magnetic flux density of the present invention will be described. The soft magnetic metal particle phase is a phase having the same composition as the soft magnetic metal powder (iron powder, Fe-Al-based iron-based soft magnetic alloy powder, etc.). Of the grain boundary phases, the ZnO-type phase having a hexagonal structure is generally represented by Zn1 ₊ xO, and has a range of x = 0 to 0.001. The component of the ZnO type phase is at least one of Fe, Al, Ni, Cr, Mn, Si, Li, Na, K, Mg, Ga, Ge, Ag, In, Sn, Sb, Ba, and Bi in addition to Zn. Also included in the present invention are those containing one kind of unavoidable impurities at a maximum of 5% by mass with respect to Zn, and in particular, at least one of Li, Na, and K, which can be monovalent ions, has a maximum of at least one kind with respect to Zn. When the content is 5% by mass, there is an effect of increasing the specific resistance value of the composite soft magnetic material and improving the magnetic performance. Among the grain boundary phases, the mixed oxide phase of Fe and Zn having a cubic structure is an oxidation composed of γ (Fe, Zn) ₂ O ₃ , (Fe, Zn) Fe ₂ O ₄ , and (Fe, Zn) O. And a mixed phase of Al, Ni, Cr, Mn, Si, Li, Na, K, Mg, Ga, Ge, Ag, In, Sn, Sb, Ba, and Bi in addition to (Fe, Zn). The present invention also includes those containing at least one of unavoidable impurities at a maximum of 20% by mass with respect to Fe + Zn.
The ZnO-type phase having a hexagonal structure and the mixed oxide phase of Fe and Zn having a cubic structure all have an average crystal grain size in order to obtain a composite soft magnetic material having high density, high strength and high magnetic flux density. It is preferable that the fine particles have a diameter of 1 to 500 nm. If the average crystal grain size is smaller than 1 nm, high strength cannot be obtained. A more preferred range of the average crystal grain size of the ZnO type phase having a hexagonal structure and the mixed oxide phase of Fe and Zn having a cubic structure in the grain boundary phase is 1 to 200 nm, and further preferably 1 to 80 nm. .

Next, a method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance according to the present invention will be described.
The soft magnetic metal powder for producing the zinc oxide-coated soft magnetic metal powder used in the method for producing a composite soft magnetic sintered material having a high strength, a high magnetic flux density and a high resistance according to the present invention has an average particle size of 5 to 5. It is preferable to use a soft magnetic metal powder in the range of 150 μm. The reason is that if the average particle size is too small, the compressibility of the powder decreases, and the volume ratio of the soft magnetic metal powder decreases, so that the value of the saturation magnetic flux density decreases. If it is larger than 150 μm, the eddy current inside the soft magnetic metal powder increases and the magnetic permeability at high frequencies decreases, which is not preferable.
A mixed powder is prepared by adding 0.02 to 10% by mass (preferably 0.1 to 5% by mass) of Zn powder to a soft magnetic metal powder having an average particle size of 5 to 150 μm, When the mixed powder is stirred in a vacuum or a reduced-pressure atmosphere of a non-oxidizing gas while maintaining the temperature at 350 to 400 ° C., the metal Zn is vaporized and evaporated, and the vaporized Zn adheres to the surface of the soft magnetic metal powder. A Zn alloy layer, which is an alloy layer mainly composed of a metal Zn layer and / or an alloy Γ phase (a phase in which part of Fe ₄ Zn ₉ , Fe ₃ Zn ₁₀ or Fe is replaced by Al, Ni, Cr, Si) As a result, a Zn alloy layer-coated soft magnetic metal powder is obtained. The zinc powder used at this time preferably has a particle size of 300 μm or less.
Metals M (Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Sr, Y, Zr, Nb, Mo, Pd, Ta , W, Au) as impurities, low-purity zinc powder or zinc alloy powder containing 10% by mass or less can be used. This is because Zn evaporates first during heating and stirring to form a Zn deposited film on the surface of the soft magnetic metal powder, and the evaporation of M metal contained in low-purity zinc powder or zinc alloy powder is very small. This is because the amount of M metal contained in the Zn deposited film on the surface of the soft magnetic metal powder is extremely small and negligible.
In addition, a metal Me (Li, Mg, Al, Ga, Ge, Ag, In, Sn, Sb, Ba, Bi) powder having a relatively low melting point is mixed with a soft magnetic metal powder together with a Zn powder or with a Zn-Me alloy powder. When mixed with the soft magnetic metal powder and heated and stirred, an alloy of Zn and Me or a Zn alloy deposited film is formed on the surface of the soft magnetic metal powder.
When the Zn alloy layer-coated soft magnetic metal powder thus produced is heated in an oxidizing atmosphere such as carbon dioxide gas at a temperature of 300 to 1000 ° C. while stirring, the Zn alloy layer is oxidized and the surface of the soft magnetic metal powder is oxidized. A zinc oxide film is formed on the substrate to obtain a zinc oxide-coated soft magnetic metal powder.

This zinc oxide-coated soft magnetic metal powder is mixed with glass powder to produce a mixed powder, and when this mixed powder is sintered, the zinc oxide film and the glass have good adhesion, so the zinc oxide-coated soft magnetic metal powder Is strongly bonded with glass to obtain a composite soft magnetic sintered material having high strength and high specific resistance. Further, in this composite soft magnetic sintered material, the amount of glass powder to be added is 0.05 to 10% by mass (more preferably, 0.05 to 5% by mass), and since the amount is relatively small, high magnetic flux is obtained. Density can be maintained.

In the method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance according to the present invention, the glass powder added to the zinc oxide-coated soft magnetic metal powder is SiO ₂ —B ₂ O ₃ —Al ₂ O ₃ Glass, SiO ₂ —BaO—Al ₂ O ₃ glass, SiO ₂ —BaO—B ₂ O ₃ glass, SiO ₂ —BaO—Li ₂ O ₃ glass, SiO ₂ —B ₂ O ₃ —CaO glass , SiO ₂ -MgO-Al ₂ O ₃ based glass, B ₂ O ₃ -Li may be a glass powder used for the ceramic low-temperature sintering, such as ₂ O ₃ based glass, but other, PbO-B ₂ O ₃ based glass, PbO-B ₂ O ₃ -ZnO based glass, Bi ₂ O ₃ -B ₂ O ₃ based glass, Li ₂ O-ZnO-based glass, SiO ₂ -B ₂ O ₃ -PbO type glass, Al ₂ O ₃ -B ₂ O ₃ -PbO based glass, SnO-P ₂ O ₅ based glass It is more preferable ZnO-P ₂ O ₅ based glass, softening temperature, etc. with a phosphate-based glass, such as CuO-P ₂ O ₅ based glass is a glass powder having a low softening temperature below 500 ℃. The average particle size of these glass powders is preferably finer as the glass powder has a higher softening point, and is preferably in the range of 0.03 to 20 μm.

In the method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance according to the present invention, the temperature at which the mixed powder composed of the zinc oxide-coated soft magnetic metal powder and the glass powder is sintered is 300 to 1000. C. (more preferably 400 to 800 C.). The reason is that if the sintering temperature is lower than 300 ° C., the glass powder does not melt, and therefore the bonding between the zinc oxide film and the glass is not sufficiently performed, so that the strength of the obtained composite soft magnetic sintered material is insufficient. On the other hand, on the other hand, sintering at a temperature exceeding 1000 ° C. is not preferable because the specific resistance decreases. The atmosphere for sintering the mixed powder comprising the zinc oxide-coated soft magnetic metal powder and the glass powder may be any of air, hydrogen, inert gas, nitrogen gas, carbon dioxide gas, or vacuum. A gas atmosphere is most preferred.

  According to the present invention, it is possible to provide a composite soft magnetic sintered material having a high strength and a high resistance and a high magnetic flux density by a simple method, which brings an excellent effect in the electric and electronic industries.

Examples 1 to 10 and Comparative Examples 1 to 4
Pure iron powder having an average particle size of 70 μm was prepared as a raw material powder. 1% by mass of pure zinc powder was added to and mixed with the pure iron powder to prepare a mixed powder, and the mixed powder was charged into a cylindrical board in an electric furnace, and 1 × while rotating the cylindrical board. Zinc is vaporized by heating at 370 ° C. for 3 hours in a vacuum atmosphere of 10 ⁻⁵ torr, and the pure iron powder is exposed to the zinc vapor to form a Zn-coated pure iron powder having a Zn layer formed on the surface. This Zn-coated pure iron powder was heated at 800 ° C. in carbon dioxide gas to oxidize the Zn-deposited film to produce a zinc oxide-coated pure iron powder.
On the other hand, B ₂ O ₃ : 10.1% by mass, BaO: 2.9% by mass, ZnO: 1.0% by mass, SiO ₂ : 2.3% by mass, Al ₂ O ₃ : 3.0% by mass. Then, a low-melting glass having a balance of PbO was prepared, and the low-melting glass was finely pulverized with a ball mill to produce a low-melting glass powder having an average particle diameter of 1 μm.
The low melting point glass powder is mixed with the zinc oxide-coated pure iron powder at a ratio shown in Table 1 to prepare a mixed powder, and the mixed powder is put into a mold, and press-molded at a pressure of 980 MPa to form an outer layer. A ring-shaped green compact having a diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm was formed, and the obtained ring-shaped green compact was sintered in an Ar gas atmosphere at a temperature shown in Table 1 to form a ring. A composite soft magnetic sintered material made of a sintered body was produced. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 1. Further, the composite soft magnetic sintered material was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 1.
Further, the structure of the sintered body was observed with a transmission electron microscope, and the presence or absence of the grain boundary phase of the present invention surrounding the soft magnetic metal particle phase (pure iron phase), and the hexagonal ZnO type phase and cubic Fe The average particle size of the mixed oxide phase of Zn was measured, and the results are shown in Table 1.
Further, FIG. 1 shows a schematic diagram obtained by observing the structure of the composite soft magnetic sintered material produced in Example 1 with a transmission electron microscope. As shown in FIG. 1, a soft magnetic metal particle phase 1 composed of αFe crystal grains and a grain boundary phase 4 surrounding the soft magnetic metal particle phase 1, wherein the grain boundary phase 4 is a ZnO type having a hexagonal structure A phase 3, a mixed oxide phase 2 of Fe and Zn having a cubic structure and a glass phase 5, and the ZnO type phase 3 having a hexagonal structure is mainly dispersed in contact with the soft magnetic metal particle phase 1. The mixed oxide phase 2 of Fe and Zn having the cubic structure is dispersed in contact with the ZnO type phase 3 having the hexagonal structure, and the glass phase 5 is formed of Fe and Zn having the cubic structure. And a ZnO-type phase 3 having a hexagonal structure and a mixed oxide phase 2 of Fe and Zn having a structure sandwiched between and in contact with the mixed oxide phase 2 of It can be seen that an average particle diameter is composed of a fine particle phase of 10 nm.

Conventional example 1
The pure iron powder and low melting point glass prepared in Examples 1 to 10 and Comparative Examples 1 to 4 were mixed and mixed in proportions shown in Table 1 to prepare a mixed powder, and the mixed powder was subjected to a temperature shown in Table 1. In the same manner as in Examples 1 to 10 and Comparative Examples 1 to 4, a composite soft magnetic sintered material composed of a ring sintered body was obtained. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 1. Further, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 1.

  From the results shown in Table 1, the composite soft magnetic sintered materials produced in Examples 1 to 10 have the grain boundary phase of the present invention and are more deflected than the composite soft magnetic sintered material produced in Conventional Example 1. It can be seen that the material exhibits excellent properties in strength, specific resistance and magnetic flux density. However, it can be seen that any of the composite soft magnetic sintered materials produced in Comparative Examples 1 to 4 is not preferable in any of the bending strength, the specific resistance, and the magnetic flux density.

Examples 11 to 20 and Comparative Examples 5 to 8
As the raw material powder, an atomized Fe-Al-based iron-based soft magnetic alloy powder having an average particle size of 70 µm, the composition of which was Al: 5% by mass, and the balance: Fe was prepared.
0.1 mass% of Zn-4 mass% Al alloy powder is added to and mixed with the Fe-Al iron-based soft magnetic alloy powder to prepare a mixed powder, and the mixed powder is applied to a cylindrical board in an electric furnace. The zinc alloy is charged and heated to 400 ° C. for 2 hours in a vacuum atmosphere of 1 × 10 ⁻⁵ torr while rotating the cylindrical board to vaporize the zinc alloy. By exposing the magnetic alloy powder, a Zn alloy-coated Fe—Al soft magnetic alloy powder having a Zn alloy layer on its surface was produced.
This Zn alloy layer-coated Fe—Al soft magnetic alloy powder is heated at 800 ° C. in carbon dioxide gas to oxidize the zinc alloy layer to form a zinc oxide layer, and the zinc oxide coated Fe—Al soft magnetic alloy powder Was prepared. Table 2 shows a low-melting glass powder having an average particle diameter of 1 μm composed of 50% by mass of P ₂ O ₅ , 30% by mass of ZnO, and 20% by mass of SnO in the zinc oxide-coated Fe—Al soft magnetic alloy powder. A mixed powder is prepared by adding and mixing the mixed powder in an amount as required, and the mixed powder is placed in a mold and press-molded at a pressure of 980 MPa to form a ring-shaped green compact having an outer diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm. Then, the obtained ring-shaped green compact was sintered at a temperature shown in Table 2 in an inert gas atmosphere to produce a composite soft magnetic sintered material comprising a ring-shaped sintered body. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 2. Further, the composite soft magnetic sintered material was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 2.

Conventional example 2
The atomized Fe-Al-based iron-based soft magnetic alloy powder and the low melting point glass powder prepared in Examples 11 to 20 and Comparative Examples 5 to 8 were blended and mixed in proportions shown in Table 2 to prepare a mixed powder. The mixed powder was sintered at the temperature shown in Table 2 to obtain a composite soft magnetic sintered material composed of a ring sintered body in the same manner as in Examples 11 to 20 and Comparative Examples 5 to 8. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 2. Further, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 2.

  From the results shown in Table 2, the composite soft magnetic sintered materials produced in Examples 11 to 20 are superior in the transverse rupture strength, the specific resistance and the magnetic flux density as compared with the composite soft magnetic sintered material produced in Conventional Example 2. It can be seen that the characteristics are shown. However, it can be seen that the composite soft magnetic sintered materials produced in Comparative Examples 5 to 8 are not preferable because at least one of bending strength, specific resistance and magnetic flux density is inferior.

Examples 21 to 30 and Comparative Examples 9 to 12
As the raw material powder, an atomized Fe-Ni-based iron-based soft magnetic alloy powder having an average particle size of 90 µm, the composition of which was Ni: 20% by mass, and the balance: Fe was prepared.
Pure zinc powder was added to the Fe-Ni iron-based soft magnetic alloy powder in an amount of 5% by mass and mixed to prepare a mixed powder. The mixed powder was charged into a cylindrical board in an electric furnace. Is heated in a vacuum atmosphere of 1 × 10 ⁻⁵ torr at a temperature of 400 ° C. for 2 hours to vaporize zinc metal, and by exposing the Fe—Ni soft magnetic alloy powder to the zinc vapor, A Zn-coated Fe-Ni soft magnetic alloy powder having a surface coated with a Zn layer was produced. This Zn-coated Fe-Ni soft magnetic alloy powder is heated at 750 ° C in carbon dioxide gas to oxidize the zinc component layer to form a zinc oxide layer, thereby producing a zinc oxide-coated Fe-Ni soft magnetic alloy powder. did.
A low-melting glass powder having an average particle size of 1.5 μm, comprising P ₂ O ₅ : 40% by mass, PbO: 20% by mass and ZnO: 40% by mass, was added to the zinc oxide-coated Fe—Ni soft magnetic alloy powder in Table 3. A mixed powder is prepared by adding and mixing in the amount indicated in (1) above, and the mixed powder is placed in a mold and press-molded at a pressure of 980 MPa to form a ring-shaped pressure having an outer diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm. The powder was molded, and the obtained ring-shaped green compact was sintered in an inert gas atmosphere at a temperature shown in Table 3 to produce a composite soft magnetic sintered material composed of a ring-shaped sintered body. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 3. Further, the composite soft magnetic sintered material was wound and the magnetic flux density was measured with a BH tracer. The results are shown in Table 3.

Conventional example 3
Atomized Fe—Ni-based iron-based soft magnetic alloy powders prepared in Examples 21 to 30 and Comparative Examples 9 to 12 and a low melting glass powder were blended in a ratio shown in Table 3 and mixed to prepare a mixed powder. This mixed powder was sintered at the temperature shown in Table 3 to obtain a composite soft magnetic sintered material composed of a ring sintered body in the same manner as in Examples 21 to 30 and Comparative Examples 9 to 12. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 3. Further, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 3.

  From the results shown in Table 3, the composite soft magnetic sintered materials manufactured in Examples 21 to 30 are superior in the transverse rupture strength, the specific resistance, and the magnetic flux density as compared with the composite soft magnetic sintered material manufactured in Conventional Example 3. It can be seen that the characteristics are shown. However, it can be seen that the composite soft magnetic sintered materials produced in Comparative Examples 9 to 12 are not preferable because at least one of the bending strength, the specific resistance and the magnetic flux density is inferior.

Examples 31 to 40 and Comparative Examples 13 to 16
As the raw material powder, an atomized Fe—Cr-based soft magnetic alloy powder having an average particle diameter of 70 μm, a composition of which was composed of 10% by mass of Cr and the balance of Fe was prepared.
0.3 mass% of pure zinc powder was added to and mixed with the Fe-Cr iron-based soft magnetic alloy powder to prepare a mixed powder, and the mixed powder was charged into a cylindrical board in an electric furnace, The zinc metal is vaporized by heating the substrate at a temperature of 350 ° C. for 2 hours in a vacuum atmosphere of 1 × 10 ⁻⁵ torr while rotating the board, thereby exposing the Fe—Cr soft magnetic alloy powder to the zinc vapor. Thus, a Zn-coated Fe-Cr-based soft magnetic alloy powder whose surface was coated with a Zn layer was prepared. This Zn-coated Fe-Cr soft magnetic alloy powder was heated at 750 ° C in carbon dioxide gas to oxidize the zinc layer to form a zinc oxide layer, thereby producing a zinc oxide-coated Fe-Cr soft magnetic alloy powder. .
A low-melting glass powder prepared in Examples 11 to 20 and Comparative Examples 5 to 8 was added to the zinc oxide-coated Fe-Cr soft magnetic alloy powder in an amount shown in Table 4 and mixed to prepare a mixed powder. This mixed powder was placed in a mold and press-molded at a pressure of 980 MPa to form a ring-shaped green compact having an outer diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm. By sintering at a temperature shown in Table 4 in an active gas atmosphere, a composite soft magnetic sintered material composed of a ring-shaped sintered body was produced. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 4. Further, the composite soft magnetic sintered material was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 4.

Conventional example 4
Table 4 shows the low melting point glass powders prepared in Examples 11 to 20 and Comparative Examples 5 to 8 for the atomized Fe-Cr based iron-based soft magnetic alloy powders prepared in Examples 31 to 40 and Comparative Examples 13 to 16. A mixed powder is prepared by mixing and mixing in a ratio, and this mixed powder is sintered at a temperature shown in Table 4 to form a ring sintered body in the same manner as in Examples 31 to 40 and Comparative Examples 13 to 16. A composite soft magnetic sintered material was obtained. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 4. Further, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 4.

  From the results shown in Table 4, the composite soft magnetic sintered materials produced in Examples 31 to 40 are more excellent in bending strength, specific resistance and magnetic flux density than the composite soft magnetic sintered material produced in Conventional Example 4. It can be seen that the characteristics are shown. However, it can be seen that the composite soft magnetic sintered materials produced in Comparative Examples 13 to 16 are not preferable because at least one of the bending strength, the specific resistance and the magnetic flux density is inferior.

Examples 41 to 50 and Comparative Examples 17 to 20
As the raw material powder, an atomized Fe-Si-Al-based iron-based soft magnetic alloy powder having an average particle diameter of 70 µm, a composition of which is composed of 3% by mass of Si, 3% by mass of Al and the balance being Fe was prepared. 0.8 mass% of Zn-4 mass% Al alloy powder is added to and mixed with the Fe-Si-Al iron-based soft magnetic alloy powder to prepare a mixed powder, and the mixed powder is formed into a cylindrical shape in an electric furnace. The zinc alloy was charged into a board and heated at a temperature of 400 ° C. for 2 hours in a vacuum atmosphere of 1 × 10 ⁻⁵ torr while rotating the cylindrical board to vaporize the zinc alloy. A Zn-alloy-coated Fe-Si-Al-based soft magnetic alloy powder having a Zn alloy layer formed on its surface by exposing the -Al-based soft magnetic alloy powder was produced.
This Zn alloy-coated Fe-Si-Al soft magnetic alloy powder is heated at 800 ° C. in carbon dioxide gas to oxidize the zinc alloy layer to form a zinc oxide layer. A magnetic alloy powder was produced.
The low-melting glass powders prepared in Examples 21 to 30 and Comparative Examples 9 to 12 were added to the obtained zinc oxide-coated Fe-Si-Al soft magnetic alloy powder in an amount shown in Table 5 and mixed to obtain a mixed powder. The mixed powder was put into a mold, and press-molded at a pressure of 980 MPa to form a ring-shaped green compact having an outer diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm. The powder was sintered at a temperature shown in Table 5 in an inert gas atmosphere to produce a composite soft magnetic sintered material comprising a ring-shaped sintered body. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 5. Further, the composite soft magnetic sintered material was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 5.

Conventional example 5
Table 5 shows the low melting point glass powder prepared in Examples 21 to 30 and Comparative Examples 9 to 12 for the atomized Fe-Si-Al based iron-based soft magnetic alloy powder prepared in Examples 41 to 50 and Comparative Examples 17 to 20. A mixed powder was prepared by mixing and mixing at the indicated ratios, and the mixed powder was sintered at the temperature shown in Table 5 to obtain a ring sintered body in the same manner as in Examples 41 to 50 and Comparative Examples 17 to 20. A composite soft magnetic sintered material was obtained. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 5. Further, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 5.

  From the results shown in Table 5, the composite soft magnetic sintered materials produced in Examples 41 to 50 are superior in the transverse rupture strength, the specific resistance and the magnetic flux density as compared with the composite soft magnetic sintered material produced in Conventional Example 5. It can be seen that the characteristics are shown. However, it can be seen that the composite soft magnetic sintered materials produced in Comparative Examples 17 to 20 are not preferable because at least one of the bending strength, the specific resistance and the magnetic flux density is inferior.

Examples 51 to 60 and Comparative Examples 21 to 24
As the raw material powder, an atomized Fe-Si-based iron-based soft magnetic alloy powder having an average particle diameter of 70 µm, the composition of which is Si: 3% by mass, and the balance: Fe was prepared. 0.8 mass% of pure Zn powder is added to and mixed with the Fe-Si iron-based soft magnetic alloy powder to prepare a mixed powder, and the mixed powder is charged into a cylindrical board in an electric furnace, and The zinc metal is vaporized by heating the substrate at a temperature of 400 ° C. for 2 hours in a vacuum atmosphere of 1 × 10 ^-5 torr while rotating the board, exposing the Fe—Si soft magnetic alloy powder to the zinc vapor. Thus, a Zn-coated Fe-Si-based soft magnetic alloy powder having a Zn layer formed on the surface thereof was produced.
This Zn-coated Fe-Si soft magnetic alloy powder was heated at 800 ° C in carbon dioxide gas to oxidize the Zn layer to form a zinc oxide layer, thereby producing a zinc oxide-coated Fe-Si soft magnetic alloy powder. .
The low melting point glass powder prepared in Examples 11 to 20 and Comparative Examples 5 to 8 was added to the obtained zinc oxide-coated Fe-Si soft magnetic alloy powder in an amount shown in Table 6 and mixed to prepare a mixed powder. The mixed powder was put into a mold and press-molded at a pressure of 980 MPa to form a ring-shaped green compact having an outer diameter of 35 mm, an inner diameter of 25 mm, and a height of 5 mm. Was sintered in an inert gas atmosphere at a temperature shown in Table 6 to produce a composite soft magnetic sintered material comprising a ring-shaped sintered body. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 6. Further, the composite soft magnetic sintered material was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 6.

Conventional example 6
The low melting point glass powder prepared in Examples 11 to 20 and Comparative Examples 5 to 8 is shown in Table 6 to the atomized Fe-Si based iron-based soft magnetic alloy powder prepared in Examples 51 to 60 and Comparative Examples 21 to 24. A mixed powder was prepared by mixing and mixing in a ratio, and the mixed powder was sintered at the temperature shown in Table 6 to obtain a ring sintered body in the same manner as in Examples 51 to 60 and Comparative Examples 21 to 24. A composite soft magnetic sintered material was obtained. The bending strength and specific resistance of the composite soft magnetic sintered material thus obtained were measured, and the results are shown in Table 6. Furthermore, the composite soft magnetic sintered material was wound, the ring sintered body was wound, and the magnetic flux density was measured with a BH tracer. The results are shown in Table 6.

  From the results shown in Table 6, the composite soft magnetic sintered materials produced in Examples 51 to 60 are superior in the transverse rupture strength, the specific resistance and the magnetic flux density as compared with the composite soft magnetic sintered material produced in Conventional Example 6. It can be seen that the characteristics are shown. However, it can be seen that the composite soft magnetic sintered materials produced in Comparative Examples 21 to 24 are not preferable because at least one of the bending strength, the specific resistance and the magnetic flux density is inferior.

FIG. 2 is a schematic view of a structure of the composite soft magnetic sintered material of the present invention observed by a transmission electron microscope.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Soft magnetic metal particle phase 2 Mixed oxide phase of Fe and Zn 3 ZnO type phase 4 Grain boundary phase 5 Glass phase

Claims (11)

A soft magnetic metal particle phase and a grain boundary phase surrounding the soft magnetic metal particle phase, wherein the grain boundary phase is a ZnO type phase having a hexagonal structure, a mixed oxide phase of Fe and Zn having a cubic structure, and The ZnO-type phase having a hexagonal structure, which is composed of a glass phase, is dispersed in contact with the soft magnetic metal particle phase, and the mixed oxide phase of Fe and Zn having the cubic structure has the ZnO-type phase. High density, high strength and high density characterized in that the glass phase has a structure in which the glass phase is sandwiched and dispersed in contact with the mixed oxide phase of Fe and Zn having the cubic structure. Composite soft magnetic sintered material with magnetic flux density. The ZnO-type phase having a hexagonal structure and the mixed oxide phase of Fe and Zn having a cubic structure each have a structure composed of a fine particle phase having an average particle diameter of 1 to 500 nm. 2. A composite soft magnetic sintered material having high density, high strength and high magnetic flux density according to 1. The soft magnetic metal particle phase is iron, Fe-Al-based soft magnetic alloy, Fe-Ni-based soft magnetic alloy, Fe-Cr-based soft magnetic alloy, Fe-Si-Al-based soft magnetic alloy 3. The composite soft magnetic sintered material having a high density, a high strength and a high magnetic flux density according to claim 1 or 2, wherein the composite soft magnetic material has a particle phase of any one of an alloy and an Fe-Si-based iron-based soft magnetic alloy. . A zinc oxide-coated soft magnetic metal powder having a zinc oxide layer formed on the surface of the soft magnetic metal powder is prepared, and a mixed powder obtained by adding and mixing glass powder to the zinc oxide-coated soft magnetic metal powder is pressed, A method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance, characterized by sintering at a temperature of 300 to 1000 ° C. after molding. A zinc oxide-coated iron powder having a zinc oxide layer formed on the surface of the iron powder is prepared, and a mixed powder obtained by adding and mixing glass powder to the zinc oxide-coated iron powder is compacted and molded. A method for producing a composite soft magnetic sintered material having high strength, high magnetic flux density and high resistance, characterized by sintering at 300 to 1000 ° C. A zinc oxide-coated Fe-Al-based iron-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of an Fe-Al-based iron-based soft-magnetic alloy powder is produced, and the zinc oxide-coated Fe-Al-based iron-based soft magnetic alloy powder is produced. A mixed soft material having high strength, high magnetic flux density and high resistance, characterized in that a mixed powder obtained by adding and mixing glass powder into a powder is compacted and molded, and then sintered at a temperature of 300 to 1000 ° C. Manufacturing method of magnetic sintered material. A zinc oxide-coated Fe-Ni-based iron-based soft magnetic alloy powder in which a zinc oxide layer is formed on the surface of an Fe-Ni-based iron-based soft-magnetic alloy powder is produced. A mixed soft material having high strength, high magnetic flux density and high resistance, characterized in that a mixed powder obtained by adding and mixing glass powder into a powder is compacted and molded, and then sintered at a temperature of 300 to 1000 ° C. Manufacturing method of magnetic sintered material. A zinc oxide-coated Fe-Cr-based iron-based soft magnetic alloy powder in which a zinc oxide layer is formed on the surface of an Fe-Cr-based iron-based soft-magnetic alloy powder is produced. A mixed soft material having high strength, high magnetic flux density and high resistance, characterized in that a mixed powder obtained by adding and mixing glass powder into a powder is compacted and molded, and then sintered at a temperature of 300 to 1000 ° C. Manufacturing method of magnetic sintered material. A zinc oxide-coated Fe-Si-Al-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of the Fe-Si-Al-based soft magnetic alloy powder is produced, and the zinc oxide-coated Fe-Si-Al-based soft magnetic alloy powder is produced. A high-strength, high magnetic flux density, and high-density magnetic powder characterized by sintering a mixed powder obtained by adding and mixing glass powder to an iron-based soft magnetic alloy powder, and then sintering at a temperature of 300 to 1000 ° C. A method for producing a composite soft magnetic sintered material having high resistance. A zinc oxide-coated Fe-Si-based iron-based soft magnetic alloy powder having a zinc oxide layer formed on the surface of an Fe-Si-based iron-based soft-magnetic alloy powder is produced, and the zinc oxide-coated Fe-Si-based iron-based soft magnetic alloy powder is prepared. A mixed soft material having high strength, high magnetic flux density and high resistance, characterized in that a mixed powder obtained by adding and mixing glass powder into a powder is compacted and molded, and then sintered at a temperature of 300 to 1000 ° C. Manufacturing method of magnetic sintered material. The high strength, high magnetic flux density and high resistance according to claim 4, 5, 6, 7, 8, 9 or 10, wherein the amount of the glass powder added is 0.1 to 10% by mass. A method for producing a composite soft magnetic sintered material.

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