JP2713363B2 - Fe-based soft magnetic alloy compact and manufacturing method thereof - Google Patents

Description

The present invention relates to a Fe-based soft magnetic alloy compact having excellent magnetic properties, and in particular, to a Fe-based soft magnetic alloy compact comprising a large number of fine grains. The present invention relates to a powder and a method for producing the powder. [Prior art] Transformers, motors, chokes,
For a magnetic core used for a noise filter or the like, a crystalline material such as an Fe-Si alloy, permalloy, or ferrite is used according to the application. However, the Fe-Si alloy has a problem that the iron loss increases in a relatively high frequency region because the specific resistance is small and the magnetocrystalline anisotropy is not zero. Permalloy has a problem that the iron loss at a high frequency increases because the specific resistance is small.
Ferrite has a small loss at high frequencies but a small magnetic flux density of at most 5000G.Therefore, when used with a large operating magnetic flux density, it is close to saturation, resulting in an increase in iron loss. doing. In recent years, it has been desired to reduce the size of transformers used at high frequencies such as power supply transformers used in switching regulators. In that case, however, it is necessary to increase the operating magnetic flux density. The increase in loss is a serious problem in practical use. For the purpose of reducing iron loss at high frequency and improving frequency characteristics of magnetic permeability, a compact of the above magnetic alloy may be used. This is a method in which a powder of the above-described metal is produced and solidified via an insulating layer, and an organic material is used as the insulating layer. These magnetic cores are mainly used as chokes and noise filters. However, the green compact made of the above magnetic powder has a low magnetic permeability, so that the number of windings must be increased in order to obtain a sufficient inductance. In addition, there is a problem that heat generation in practical use is large due to large iron loss. On the other hand, amorphous magnetic alloys having no crystalline structure have recently attracted attention because they exhibit excellent soft magnetic properties such as high magnetic permeability and low coercive force. These amorphous magnetic alloys are made of iron (F
e), cobalt (Co), nickel (Ni), etc.
This contains phosphorus (P), carbon (C), boron (B), silicon (Si), aluminum (Al), germanium (Ge), etc. as an amorphizing element (metalloid). Further, amorphous alloys composed of Fe, Co, Ni, and alloys such as Ti, Zr, Hf, and Nb are also known. These amorphous alloys are usually obtained in the form of ribbons, and when used as their magnetic cores, the ribbons are toroidally or U-shaped.
It is used as a wound iron core formed into a shape, an E shape, or a laminated iron core obtained by stamping and laminating a thin ribbon into a predetermined shape. However, these magnetic cores are particularly difficult to produce in U-shape and E-shape. In order to solve the above-mentioned drawbacks, a method of producing a powder of an amorphous magnetic alloy, consolidating the powder with a binder, and producing a compact is disclosed in, for example, JP-A-55-133507, 61-154014, 61-. Fifteen
4111, 61-166902 and the like. Further, a method of obtaining a high-density green compact by instantaneously compressing the powder of an amorphous magnetic alloy by an impact force is disclosed in, for example, JP-A-61-28884.
04, 62-23905 and the like. Amorphous alloys used for these compacts are mainly classified into Fe-based and Co-based,
Fe-based amorphous alloys have the advantage of higher saturation magnetic flux density and lower material cost than Co-based alloys, but generally have higher core loss and lower magnetic permeability than Co-based amorphous alloys at high frequencies. There's a problem. On the other hand, a Co-based amorphous alloy has a small high-frequency core loss and a high magnetic permeability, but has a small saturation magnetic flux density and a large change with time in the core loss and the magnetic permeability. Furthermore, since expensive Co is used as a main raw material, disadvantages in terms of price are inevitable. Such advantages and disadvantages of the Fe-based and Co-based amorphous alloys are substantially applicable even when they are used as green compacts. [Problems to be Solved by the Invention] An object of the present invention is to provide a novel soft magnetic alloy green compact having a large saturation magnetic flux density, excellent core loss and aging of the core loss, excellent magnetic permeability and other magnetic properties. Is to do. Another object of the present invention is to provide a method for producing the Fe-based soft magnetic alloy compact. [Means for Solving the Problems] As a result of intensive studies in view of the above object, the present inventors found that Fe-Si
Alloys containing -B as basic components include Cu, Nb, W, Ta, Zr, and H
By adding a combination of at least one element selected from the group consisting of f, Ti, and Mo, an appropriate heat treatment of the amorphous alloy enables the majority of the structure to be composed of fine crystal grains and Fe-based soft magnetism with excellent magnetic properties They discovered that an alloy powder could be obtained, and reached the present invention. That is, the Fe-based soft magnetic alloy compact of the present invention has the general formula: (Fe _1-a M _a ) _{100-xyz-α-β-γ} Cu _x Si _y B _z M ′ _α M ″ _β X _γ (atomic%) (where M is Co and / or Ni, and M ′ is Nb, W, Ta,
At least one element selected from the group consisting of Zr, Hf, Ti and Mo, M ″ is composed of V, Cr, Mn, Al, white metal element, Sc, Y, rare earth element, Au, Zn, Sn, Re X is at least one element selected from the group consisting of Be, C, Ge, P, Ga, Sb, As, In, and a, x, y, z, α, β and γ are respectively 0 ≦ a <0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 30, 0 ≦ z ≦ 25, 0.1 ≦ α ≦ 30, 0 ≦ β ≦ 100 0 ≦ γ ≦ 10 and 0 ≦ y + z ≦ 35 is satisfied.) A fine powder having a composition represented by the following formula is used as a starting material, and this is compacted to form a compact green compact in which at least 50% of the composition is composed of fine crystal grains. Further, the method for producing a Fe-based soft magnetic alloy compact of the present invention includes a step of obtaining the amorphous alloy fine powder by quenching a molten metal, a step of pressing the same to form a compact, and a step of heating the compact. Heat treatment process to form fine crystal grains Here, as a method for forming the green compact, a method such as a cold press, a warm press, and an explosion pressure bonding is possible.In the present invention, Cu is an essential element, and its content is included. Quantity x
Ranges from 0.1 to 3 atomic%. If less than 0.1 atomic%
There is almost no effect of reducing the core loss by the addition of Cu. On the other hand, if it is more than 3 atomic%, the core loss becomes larger than that of the non-added one. In the present invention, the particularly preferable Cu content x is 0.5 to 2 atomic%, and in this range, the core loss is particularly small. Although the cause of the core loss reducing effect of Cu is not clear, it is considered as follows. In other words, the interaction parameter between Cu and Fe is positive and the solid solubility is low, but when an appropriate amount is contained in the Fe-based amorphous alloy and heat treatment is performed, clustering of clusters of Fe atoms or Cu atoms occurs. , Composition fluctuations occur. For this reason, a large number of regions that are likely to be partially crystallized are formed, and crystallization starts with the regions as nuclei. Since these crystals are mainly composed of Fe and have almost no solid solubility of Cu, Cu is extruded around the crystal grains by crystallization, and the Cu concentration around the crystal grains increases. For this reason, it is considered that crystal grains are unlikely to grow. That is, it is considered that a large number of crystal nuclei can be formed by the addition of Cu, and the crystal grains are difficult to grow. Since the crystal grains become magnetically isotropic due to the refinement of the crystal grains, even if the
It is considered that soft magnetism comparable to that of the base amorphous alloy can be obtained. This effect is considered to be remarkable due to the presence of Nb, Ta, W, Mo, Zr, Hf, Ti, etc., and in the absence of Nb, Ta, W, Mo, Zr, Hf, Ti, etc., the crystal grains become very fine. Not done. Also Fe
It is also considered that the soft magnetic characteristics are improved due to the fact that a fine crystal phase mainly composed of γ is generated, so that the magnetostriction is reduced and the magnetic anisotropy due to internal stress-strain is reduced as compared with an Fe-based amorphous alloy or the like. Even if Nb, Ta, W, Mo, Zr, Hf, etc. are added,
When Cu is not added, the crystal grains are hard to be refined and a compound phase is easily formed, so that the magnetic properties are degraded by crystallization. Si and B are desirable for making the alloy amorphous. Because, as will be described later, generally, the Fe-based soft magnetic alloy compact of the present invention is obtained by forming fine crystal grains by heat treatment after forming an amorphous alloy fine powder once. Because there is. The reasons for limiting the contents y and z of both are as follows:
y is 30 atomic% or less, z is 0 to 25 atomic%, and y + z is 0 to
If the content is out of the range of 35 atomic%, it may be difficult to make the alloy amorphous. In the present invention, the preferable range of y is 10 to
The preferred range of z is 3 to 12 atomic% and the preferred range of y + z is 18 to 28 atomic%. Within this range, one with a small core loss can be easily obtained. In the present invention, M ′ has an action of refining crystal grains precipitated by complex addition with Cu, and Nb, W,
At least one selected from the group consisting of Ta, Zr, Hf and Mo
It is a seed element. Nb and the like have an effect of increasing the crystallization temperature of the alloy, but it is considered that the crystal grains precipitated by the interaction with Cu which forms a cluster and has an effect of lowering the crystallization temperature are refined. The content α of M ′ is 0.
If it is 1 to 30 atomic%, the effect of grain refinement is insufficient if it is less than 0.1 atomic%, and if it exceeds 30 atomic%, the saturation magnetic flux density is remarkably reduced. The preferable content α of M ′ is 2 to 8
Atomic%. Note that Nb is most preferable as M 'in terms of magnetic characteristics. Further, the addition of M 'results in a high magnetic permeability equal to or higher than that of a green compact using a Co-based high magnetic permeability amorphous alloy. The balance is substantially Fe except for impurities, but a part of Fe may be replaced by the additional component M (Co and / or Ni). The content a of M is 0 ≦ a <0.5, because when α exceeds 0.5, the core loss increases. The Fe-based soft magnetic alloy green compact of the present invention having the above composition has at least 50% or more of the alloy structure composed of fine crystal grains. These crystal grains are mainly composed of α-Fe, and it is considered that Si, B, and the like are in a solid solution. These crystal grains, when measured at their maximum dimensions, have a remarkably small average particle size of 500 ° or less and are uniformly distributed in the alloy structure. The portion other than the fine crystal grains in the alloy structure is mainly amorphous.
The Fe-based soft magnetic alloy compact of the present invention shows sufficiently excellent magnetic properties even when the ratio of fine crystal grains is substantially 100%. Further, the Fe-based soft magnetic alloy compact of the present invention may contain V, Cr, Mn, Al, a white metal element, and the like, as necessary, in addition to the above components. C, Ge, P, Ga
Etc. may be included. It is needless to say that unavoidable impurities such as N, O and S can be regarded as the same as the alloy composition of the present invention even if they are contained to such an extent that the desired characteristics are not deteriorated. Next, a method for producing the Fe-based soft magnetic alloy compact of the present invention will be described. First, as a method of forming the amorphous alloy powder, from a molten metal of the above predetermined composition, by a known liquid quenching method such as a single roll method, a multi-roll method, to form a ribbon-shaped amorphous alloy,
There is a method of pulverizing the powder by heat embrittlement followed by grinding. There is also a method of directly obtaining an amorphous alloy fine powder from a molten metal having a predetermined composition by a known liquid quenching method such as an atomizing method and a cavitation method. The latter method is generally superior in mass productivity, but the former method can easily obtain scaly powder, and is used depending on the purpose. This amorphous alloy fine powder may contain a slight crystal phase, but is desirably as amorphous as possible in order to uniformly generate fine crystal grains by a subsequent heat treatment. Next, in order to consolidate this into a green compact, a binder (for example, a phenol resin or an epoxy resin may be used, but if a heat treatment is performed after press molding, a heat-resistant binder such as an inorganic varnish is used). Is desirable) and press-molding. Also, in order to make this into a compact without using a binder, use the deformation due to viscous flow in the so-called warm region,
The amorphous alloy powder can be formed into a bulk by pressing and consolidating the amorphous alloy powder in the vicinity of the crystallization temperature of the amorphous alloy. It is also possible to form a lump by a so-called explosion molding technique. When the green compact is used as an electric component, it is preferable to provide an insulating layer between the powders for the purpose of reducing eddy current loss. The method can be achieved by previously oxidizing the surface of the amorphous alloy powder, which is the starting material, or by adding water glass, metal alkoxide, ceramic ultrafine powder, etc., and then forming a green compact. . In addition, all of the powders described above are amorphous powders. However, crystallization heat treatment may be performed on the amorphous ribbon, and the powder may be pulverized. However, the heat treatment can be performed in the form of a ribbon or powder, but it is preferable to perform the heat treatment after forming the green compact except when the magnetostriction is close to zero. The method is usually carried out in a vacuum or in an atmosphere of an inert gas such as hydrogen or nitrogen for a certain period of time. The heat treatment temperature and time vary depending on the shape, size, composition and the like of the magnetic core made of the amorphous alloy fine powder, but it is generally desirable that the temperature is 450 ° C. to 700 ° C. for about 5 minutes to 24 hours. If the heat treatment temperature is lower than 450 ° C., crystallization hardly occurs, and the heat treatment takes too much time. If the temperature is higher than 700 ° C., coarse crystal grains may be generated, and fine crystal grains cannot be obtained uniformly. When the heat treatment time is less than 5 minutes, it is difficult to make the entire processed alloy a uniform temperature, and the magnetic properties are likely to vary,
If the time is longer than 24 hours, not only the productivity will deteriorate, but also the magnetic properties will be likely to deteriorate due to excessive growth of crystal grains. Preferred heat treatment conditions are 500 to 650 ° C. for 5 minutes to 6 hours in consideration of practicality and uniform temperature control. The heat treatment atmosphere is preferably an atmosphere of Ar, N ₂ , H _2, etc.
An oxidizing atmosphere such as the air may be used. Cooling can be appropriately performed by air cooling, furnace cooling, or the like. In some cases, multi-stage heat treatment can be performed. [Example] Hereinafter, an example of the present invention will be described. Example 1 A ribbon having a width of 20 mm and a thickness of 18 μm was produced by a single roll method from a molten metal having a composition consisting of 1% of Cu, 15% of Si, 9% of B, 9% of Nb, 1% of Cr and the balance substantially of Fe. When the X-ray diffraction of this ribbon was measured, a halo pattern typical of an amorphous alloy as shown in FIG. 1A was obtained. FIG. 2A shows a transmission electron micrograph (magnification: 300,000) of this ribbon. As is clear from X-ray diffraction and FIG. 2 (a), the obtained ribbon was almost completely amorphous. Next, this amorphous ribbon was heated at 300 ° C. for 30 minutes in a nitrogen atmosphere, and then pulverized by a vibration mill to obtain a powder having a size of 48 mesh or less. The result of observing the shape of the obtained powder with a scanning electron microscope (SEM) is shown in FIG. 3, and it can be seen that the shape of the powder is scaly. On the other hand, as a result of X-ray diffraction of this powder, almost the same halo pattern as shown in FIG. 1A was obtained. At this stage, it was confirmed that the powder was substantially amorphous. Next, 7 wt% of a heat-resistant inorganic varnish (modified alkyl silicate) was added as a binder to the obtained powder, and warm pressing was performed at about 250 ° C. to produce a dust core having an outer diameter of 20 mm, an inner diameter of 12 mm, and a thickness of 6 mm. . FIG. 4 shows a cross-sectional macrostructure of the obtained dust core. This magnetic core was heat-treated at 550 ° C. for 1 hour in a nitrogen gas atmosphere, and was gradually cooled. At the same time, the amorphous powder was heat-treated under the same conditions and subjected to X-ray diffraction. As a result, a crystal peak was observed as shown in FIG. 1 (b). FIG. 2 (b) is a transmission electron micrograph (30
It is clear that most of the structure after the heat treatment is composed of fine crystal grains. The average grain size of the crystal grains was about 100 °. The shape of the crystal grains of the alloy of the present invention to which Cu and Nb are added in combination is nearly spherical, and the average grain size is remarkably refined to about 100 °. From the X-ray diffraction pattern and the analysis by the transmission electron microscope, it is presumed that these crystal grains are α-Fe in which Si, B and the like are dissolved. When Cu was not added, the crystal grains became large and hard to be miniaturized. Thus, it was confirmed that the combined addition of Cu and Nb significantly changed the size and morphology of the obtained crystal grains. Next, the core loss W at a peak value Bm of magnetic flux density of 2 kG and a frequency of 100 KHz for the above-mentioned dust core before and after the heat treatment.
_When measuring _{2 / 100K} , the one before heat treatment was 7500mW / c
c, that after heat treatment was 530 mW / cc. From this, it can be seen that the core loss is significantly reduced by uniformly forming fine crystal grains in the amorphous alloy by the heat treatment of the present invention. Example 2 Under the same conditions as in Example 1, an Fe-based amorphous dust core having the composition shown in Table 1 below was produced. Each of the obtained alloys was divided into two parts. One part was subjected to a heat treatment under the same conditions as in Example 1, and the other part was subjected to a conventional heat treatment (40
(0 ° C. × 1 hour), and the core loss W _{2 / 100K} at 100 kHz and 2KG was measured for each. The results are shown in Table 1. It can be seen that the core loss is remarkably reduced by uniformly forming fine crystal grains in the amorphous alloy by the heat treatment of the present invention in any composition. In addition, it can be seen that, for the alloys shown in the comparative example, in which the amorphous state was maintained by the conventional heat treatment, no significant decrease in the core loss was observed in any of the compositions. Example 3 In the same manner as in Example 1, Fe _73-x Cu _x Si ₁₄ B ₉ Nb ₃ Cr ₁
An amorphous alloy compact having a composition represented by the following formula (0 ≦ x ≦ 3.5) is prepared, and each sample is subjected to the following optimal heat treatment temperature at 1
Time heat treatment, peak value of magnetic flux density Bm = 2kG, frequency f = 1
The core loss W2 _{/ 100K} at 00 KHz was measured. Value of x (atomic%) Heat treatment temperature (° C) 0 510 0.05 515 0.1 530 0.5 550 1.0 570 1.5 570 2.0 560 2.5 540 3.0 510 3.2 500 3.5 490 Figure 5 shows Cu content x (atomic%) and core loss W _{2 / 100K}
The relationship is shown below. As is clear from FIG. 5, the core loss decreases as the Cu content x increases from 0, but when the content exceeds about 3 atomic%, the core loss becomes as large as that of the case where no Cu is added. x is 0.
When it is in the range of 1 to 3 atomic%, it can be seen that the core loss is sufficiently small. A particularly desirable range of x is 0.5 to 2 atomic%. Example 4 Fe _75.5-α Cu ₁ Si ₁₃ B _9.5 M ′ was _{prepared in} the same manner as in Example 1.
_An amorphous alloy having a composition represented by _α Ti ₁ (M ′ = Nb, W,
Ta or Mo) compacts are prepared, and each sample is heat-treated for 1 hour at the following optimum heat treatment temperature, and each core loss W
_{2 / 100K} was measured. Value of α (atomic%) Heat treatment temperature (° C.) 0 410 0.1 420 0.2 425 1.0 445 2.0 500 3.0 550 5.0 580 7.0 590 8.0 600 10.0 600 11.0 605 The results are shown in FIG. In FIG. 6, graphs A, B,
C and D show the cases where M 'is Nb, W, Ta and Mo, respectively. As is apparent from FIG. 6, the amount α of M ′ is 0.1 to 10 atomic%.
The core loss is sufficiently small in the range. M '
Core loss was particularly low at Nb. A particularly desirable range of α is 2 ≦ α ≦ 8. Example 5 An alloy having a composition of Fe ₇₂ Cu ₁ Si _13.5 B _9.5 Nb ₃ Ru ₁ was powdered by a water atomizing method, and a powder having a mesh of 48 mesh or less was obtained with a sieve. As a result of X-ray diffraction of the obtained powder,
A halo pattern similar to that shown in FIG. A was obtained, and it was confirmed that the film was almost completely amorphous. 0.7% of water glass (JIS No. 3) is added to the obtained powder, and the mixture is sufficiently stirred.
Dry at 0 ° C. for 2 hours. This powder is made into a bulk by the impact compression method, and the outer diameter is 20 mm.
A toroidal magnetic core having an inner diameter of 12 mm and a thickness of 5 mm was manufactured. The bulking was performed by an impact gun method, and the impact pressure was 7 GPa and the density of the obtained molded body was 97%. This was heat-treated at 550 ° C. for 1 hour, and the effective magnetic permeability μ _{e1K at} a saturation magnetic flux density Bs1 kHz and the core loss W _{1 / 10K} at ₁ kG, 10 kHz were measured. For comparison, Fe
The effective magnetic permeability was also measured for the base amorphous alloy green compact (composition: Fe ₇₈ B ₁₃ Si ₉ ) and ferrite (Mn-Zn system). Table 2 shows the results. Note that the method for producing the Fe-based amorphous alloy compact is as described above until the formation of the compact is Fe ₇₂ Cu ₁ Si _13.5 B _9.5 Nb
_{3 Following} the same method as Ru ₁ . The obtained green compact was annealed for 2 hours at 400 ° C., which is a temperature range for maintaining the amorphous property. Table 2 shows that the Fe-based soft magnetic alloy compact of the present invention has a higher saturation magnetic flux density than the Co-based amorphous alloy compact and the permalloy compact, and the Fe-based amorphous alloy compact. It can be seen that they have excellent magnetic permeability and core loss as compared to For this reason,
The Fe-based soft magnetic alloy compact of the present invention is suitable for choke coils and the like. Example 6 Example 1 was obtained from an amorphous alloy ribbon having the composition shown in Table 3.
A Fe-based soft magnetic alloy green compact was obtained in the same manner as described above. Table 3 shows that each green compact was treated under high temperature and high humidity (80 ° C, 95% RH).
The degree of corrosion resistance and the amount of change in core loss ΔW after holding for 0 hours Is shown. As is clear from Table 3, Ru, Rh, Pd, Os, I
The Fe-based soft magnetic alloy compact of the present invention to which r, Pt, Au, Cr, Ti, V, etc. are added has excellent corrosion resistance, and has a small deterioration of core loss under high temperature and high humidity. It is practical in some cases. Example 7 Atomic%: Cu 1%, Si 13.8%, B8.9%, Nb 3.2%, Cr 0.5
%, C1%, and the balance substantially from Fe,
A ribbon having a width of 10 mm and a thickness of 18 μm was produced by a single roll method. When the X-ray diffraction of this ribbon was measured, a halo pattern typical of an amorphous alloy was obtained. The transmission electron micrograph (magnification 300,000) of this ribbon confirmed that it was almost completely amorphous. Next, this amorphous ribbon is heated at 570 ° C. for 1 hour in a nitrogen gas atmosphere.
Heat treatment was performed for a time. According to the transmission electron micrograph (magnification 300,000), most of the structure of the ribbon after heat treatment is shown in FIG. 2 (b).
It was found that the particles consisted of fine crystal grains like those shown in FIG. The average grain size of the crystal grains was about 100 °. It has been confirmed that the crystal grains become coarse when Cu is not added,
A remarkable grain refinement effect can be obtained by adding Cu and Nb in combination. This is crushed to 48 mesh or less by a vibration mill, and the outer diameter is 20 mm, the inner diameter is 12 mm, and the thickness is 6 mm in the same manner as in Example 1.
Was prepared. On the other hand, the amorphous ribbon was subjected to a conventional heat treatment (400 ° C. × 1 hour) to maintain the amorphous state, and a dust core having the same shape was produced by the same method as described above. Regarding the dust core made of the obtained Fe-based soft magnetic alloy,
When the peak value Bm of the magnetic flux density Bm = 2 kG and the core loss W2 _{/ 100K} at a frequency of ₁₀₀ KHz were measured, the conventional heat treatment was 5500 mW / cc, and the heat treatment according to the present invention was 930 mW / cc.
Met. This indicates that the core loss is significantly reduced by uniformly forming fine crystal grains in the amorphous alloy by the heat treatment of the present invention. Example 8 Under the same conditions as in Example 7, an Fe-based dust core having the composition shown in Table 4 below was produced in the same manner as in Example 7. The values of the core loss W _{2 / 100K} are compared between the case where the heat treatment according to the present invention is performed in the state of the ribbon and the case where the conventional heat treatment for maintaining the amorphous state is performed. It can be seen that the heat treatment of the present invention can provide an alloy having low core loss and magnetic properties. Example 9 amorphous alloy ribbon having a composition of _{Fe 73-x Cu x Si 13} B 9 Nb 3 Cr 1 C 1, in the same manner as in Example 1, an outer diameter of 20 mm,
Powder magnetic cores having an inner diameter of 12 mm and a thickness of 6 mm were prepared and heat-treated at various temperatures for 1 hour. The core loss W2 _{/ 100K} at ₂ kG and 100 kHz was measured for each. The results are shown in FIG. The crystallization temperature (Tx) of the amorphous alloy used for each magnetic core was measured with a differential scanning calorimeter (DSC). The crystallization temperature Tx of each alloy is 580 ° C (x = 0) at a rate of 10 ° C / min.
And 505 ° C. (x = 0.5, 1.0, 1.5). As is clear from FIG. 7, when the Cu content (x) is 0, the core loss W _{2 / 100K} is extremely large, and when Cu is added, not only the core loss becomes small, but also the appropriate heat treatment temperature range is reduced. It can be seen that the temperature was 540 ° C to 580 ° C, which was higher than that of the Cu-free material. This temperature is DSC at a heating rate of 10 ° C / min.
It is higher than the crystallization temperature Tx measured in. As a result of observation by a transmission electron microscope, it was confirmed that in the case of a dust core using the Fe-based soft magnetic alloy of the present invention containing Cu, 50% or more of the individual powders consisted of fine crystal grains. Example 10 An alloy powder having the composition shown in Table 5 was produced by a water atomizing method, and a powder having a mesh of 48 mesh or less was obtained by sieving. As a result of X-ray diffraction of the obtained powder, a halo pattern similar to that of FIG. 1A was obtained, and it was confirmed that the powder was almost completely amorphous. Next, 7 wt% of a heat-resistant varnish made of a modified alkyl silicate was added to the obtained powder as a binder, the temperature was increased at 50 ° C./min while applying pressure, and the mixture was warm-pressed at about 530 ° C., held for 30 minutes, cooled, and cooled Diameter 20mm, inner diameter 12mm, thickness 6mm
Was prepared. As a result of X-ray diffraction of the magnetic core, a crystal peak was recognized as shown in FIG. Table 5 shows the results of measuring the effective magnetic permeability μ _e1K at 1 kHz. The Fe-based soft magnetic alloy compact of the present invention has a saturation magnetic flux density of 10 kG.
As described above, since _{μe1K of} 1000 or more is obtained, it is _{most suitable} for a noise filter and a magnetic core for a choke coil. Example 11 A flake-like amorphous alloy powder having a composition of Fe _73.5 Cu ₁ Nb ₃ Si _16.5 B ₆ was produced by a cavitation method. Next, after mixing water glass, aluminum phosphate powder acetone, and methanol with this powder, the mold was heated to 450 ° C. and kept at a pressure of 15 T / cm ² for 30 minutes to perform compacting. The obtained compact having an outer diameter of 21 mm, an inner diameter of 12 mm, and a height of 8 mm is further heated at 530 ° C.
Heat treated for 30 minutes. As a result of X-ray diffraction after measuring the magnetic properties, it was confirmed that the green compact was substantially composed of a crystalline phase. FIG. 8 shows an example of the DC superposition characteristics at 10 kHz of the dust core A of the present invention, the Mo permalloy dust core B, and the Fe-Si-Al dust core C produced. The powder magnetic core A of the present invention shows a superior DC superposition characteristic than the conventional powder magnetic core, and is suitable for a smoothing choke or the like of a switching power supply. Example 12 Fe _71.5 Cu ₁ Nb ₅ Si _15.5 B ₇ having a composition of width 5 mm and thickness 15
A μm amorphous alloy ribbon was prepared, kept at 450 ° C. for 1 hour, cooled, and crushed by a vibration mill to obtain a powder having a size of 48 mesh or less. Water glass, aluminum phosphate powder,
After mixing acetone and methanol, heat to 500 ℃, 15T / c
The powder was held at a pressure of m ² for 30 minutes and compacted. Obtained outer diameter 21m
The green compact having a diameter of 12 mm, an inner diameter of 12 mm and a height of 8 mm was further heat-treated at 570 ° C. for 30 minutes. Next, a powder coating of an epoxy resin was applied to the dust core, and the frequency characteristics of the effective magnetic permeability μe were measured. X-ray diffraction was performed after the measurement, and as a result, a crystal peak was recognized, and it was almost completely crystallized. One example of the obtained result is shown in FIG. For comparison, the frequency dependence of the effective permeability of a Mo permalloy powder core is shown. The powder magnetic core of the present invention exhibits better frequency characteristics of effective magnetic permeability than the conventional Mo permalloy powder magnetic core, and is suitable for various inductors used at high frequencies. [Effects of the Invention] As described in detail above, the core loss of the Fe-based soft magnetic alloy compact of the present invention is significantly reduced by heat treatment as compared with the conventional Fe-based amorphous alloy compact, The effect is substantially the same as that of the base amorphous alloy, the change in core loss with time is small, and the magnetic permeability is high.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 (a) is a conventional X-ray diffraction pattern before heat treatment constituting the Fe-based soft magnetic alloy compact of Example 1, FIG. 1 (b)
Fig. 2 shows the X-ray diffraction pattern after heat treatment according to the present invention, Fig. 2 (a) corresponds to Fig. 1 (a), and Fig. 2 (b) shows the transmission of the metal structure corresponding to Fig. 1 (b). Electron micrograph (× 300,000), FIG. 3 is a photograph of the particle structure according to the present invention, and FIG. 4 is Example 1.
FIG. 5 is a diagram showing the dependency of core loss on Cu content, FIG. 6 is a diagram showing M ′ content dependency of core loss, and FIG. FIG. 8 is a diagram showing the dependence of the core loss on the heat treatment temperature, FIG. 8 is a diagram showing an example of the direct current superposition characteristic, and FIG. 9 is a diagram showing an example of the frequency dependence of the effective magnetic permeability.

   ────────────────────────────────────────────────── ─── Continuation of front page    (56) References JP-A-59-179729 (JP, A)                 JP-A-61-154014 (JP, A)                 JP-A-61-166902 (JP, A)                 JP-A-62-317189 (JP, A)

Claims (1)

(57) [Claims] General formula: (Fe _1-a Ma _a ) _{100-xy-z-α-β-γ} Cu _x Si _y B _{z M′α} M ″ _β X _γ (atomic%) (where M is Co and / or Or Ni, and M ′ is Nb, W, Ta,
At least one element selected from the group consisting of Zr, Hf, Ti and Mo, M ″ is from V, Cr, Mn, Al, white metal, Sc, Y, rare earth, Au, Zn, Sn, Re. X is at least one element selected from the group consisting of Be, C, Ge, P, Ga, Sb, As, In, and X is a, x, y, z, α, β and γ are respectively 0 ≦ a <0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 30, 0 ≦
z ≦ 25,0.1 ≦ α ≦ 30,0 ≦ β ≦ 10,0 ≦ γ ≦ 10 and 0 ≦ y +
Satisfies z ≦ 35. ) Is a compact compacted from an alloy powder having a composition represented by the formula (1), wherein at least 50% of the alloy structure is composed of fine crystal grains, and when the crystal grains are measured at their maximum size, 500 mm A Fe-based soft magnetic alloy green compact having the following average particle size. 2. 2. The Fe-based soft magnetic alloy green compact according to claim 1, wherein the remainder of the structure is amorphous. 3. 2. The Fe-based soft magnetic alloy compact according to claim 1, wherein said structure is made up of substantially fine crystal grains. 4. The Fe-based soft magnetic alloy compact according to any one of claims 1 to 3, wherein 0 ≦ a <0.3,0.5 ≦
x ≦ 2,10 ≦ y ≦ 25,3 ≦ z ≦ 12,18 ≦ y + z ≦ 28,2 ≦ α ≦
8. A green compact of an Fe-based soft magnetic alloy, which is 8. 5. The Fe-based soft magnetic alloy compact according to any one of claims 1 to 4, wherein M 'is Nb. 6. The Fe-based soft magnetic alloy compact according to any one of claims 1 to 4, wherein the M 'is at least two elements including Ti, and / or the M "is Ru. , R
A Fe-based soft magnetic alloy compact comprising at least one element selected from the group consisting of h, Pd, Os, Ir, Pt, Au, Cr, and V. 7. General formula: (Fe _1-a Ma _a ) _{100-xy-z-α-β-γ} Cu _x Si _y B _{z M′α} M ″ _β X _γ (atomic%) (where M is Co and / or Or Ni, and M ′ is Nb, W, Ta,
At least one element selected from the group consisting of Zr, Hf, Ti and Mo, M ″ is from V, Cr, Mn, Al, white metal, Sc, Y, rare earth, Au, Zn, Sn, Re. X is at least one element selected from the group consisting of Be, C, Ge, P, Ga, Sb, As, In, and X is a, x, y, α, β and γ are respectively 0 ≦ a <0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 30, 0 ≦ z
≦ 25, 0.1 ≦ α ≦ 30, 0 ≦ β ≦ 10, 0 ≦ γ ≦ 10 and 0 ≦ y + z
Satisfies ≦ 35. ), Wherein at least 50% of the alloy structure is composed of fine crystal grains, and the crystal grains have an average particle size of 500 mm or less when measured at their maximum size. A method for producing an Fe-based soft magnetic alloy compact, wherein a binder and / or an electrically insulating material is interposed between powders when compacting by molding. 8. 8. The method for producing a Fe-based soft magnetic alloy compact according to claim 7, wherein the amorphous alloy ribbon is subjected to a heat treatment for forming fine crystal grains, and then turned into a fine powder. A method for producing a Fe-based soft magnetic alloy green compact, comprising performing a step. 9. 9. The method for producing an Fe-based soft magnetic alloy compact according to claim 8, wherein the heat treatment for forming fine crystal grains is performed by maintaining 450 to 700 ° C. for 5 minutes to 24 hours. A method for producing a Fe-based soft magnetic alloy green compact, comprising: 10. General formula: (Fe _1-a Ma _a ) _{100-xy-z-α-β-γ} Cu _x Si _y B _{z M′α} M ″ _β X _γ (atomic%) (where M is Co and / or Or Ni, and M ′ is Nb, W, Ta,
At least one element selected from the group consisting of Zr, Hf, Ti and Mo, M ″ is from V, Cr, Mn, Al, white metal, Sc, Y, rare earth, Au, Zn, Sn, Re. X is at least one element selected from the group consisting of Be, C, Ge, P, Ga, Sb, As, In, and X is a, x, y, α, β and γ are respectively 0 ≦ a <0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 30, 0 ≦ z
≦ 25, 0.1 ≦ α ≦ 30, 0 ≦ β ≦ 10, 0 ≦ γ ≦ 10 and 0 ≦ y + z
Satisfies ≦ 35. ), A binder and / or an electrical insulating material added to an amorphous alloy fine powder having a composition represented by formula (1), press-molded, and then heat-treated to form fine crystal grains. A method for producing a base soft magnetic alloy compact. 11. 11. The method for producing a Fe-based soft magnetic alloy compact according to claim 10, wherein the heat treatment for forming fine crystal grains is performed by holding 450 to 700 ° C. for 5 minutes to 24 hours. A method for producing a Fe-based soft magnetic alloy green compact, comprising: 12. General formula: (Fe _1-a Ma _a ) _{100-xy-z-α-β-γ} Cu _x Si _y B _{z M′α} M ″ _β X _γ (atomic%) (where M is Co and / or Or Ni, and M ′ is Nb, W, Ta,
At least one element selected from the group consisting of Zr, Hf, Ti and Mo, M ″ is from V, Cr, Mn, Al, white metal, Sc, Y, rare earth, Au, Zn, Sn, Re. X is at least one element selected from the group consisting of Be, C, Ge, P, Ga, Sb, As, In, and X is a, x, y, α, β and γ are respectively 0 ≦ a <0.5, 0.1 ≦ x ≦ 3, 0 ≦ y ≦ 30, 0 ≦ z
≦ 25, 0.1 ≦ α ≦ 30, 0 ≦ β ≦ 10, 0 ≦ γ ≦ 10 and 0 ≦ y + z
Satisfies ≦ 35. Fe) characterized by subjecting the amorphous alloy fine powder having the composition represented by) to a mass by pressing at a temperature near the crystallization temperature or by an impact force, and then performing a heat treatment to form fine crystal grains. A method for producing a base soft magnetic alloy compact. 13. In the method for producing an Fe-based soft magnetic alloy compact according to claim 12, the heat treatment for forming fine crystal grains is performed by holding 450 to 700 ° C for 5 minutes to 24 hours. A method for producing a Fe-based soft magnetic alloy green compact, comprising: