WO1991015020A1

WO1991015020A1 - Magnetic core

Info

Publication number: WO1991015020A1
Application number: PCT/JP1990/000407
Authority: WO
Inventors: Yumie Watanabe; Yumiko Takahashi; Takao Sawa; Yoshiyuki Yamauchi; Susumu Matsushita; Masami Okamura
Original assignee: Kabushiki Kaisha Toshiba
Priority date: 1990-03-27
Filing date: 1990-03-27
Publication date: 1991-10-03
Also published as: KR920702001A; DE69031338T2; EP0473782A1; EP0473782B1; DE69031338D1; EP0473782A4; KR0134508B1

Abstract

A magnetic core obtained by winding a long sheet of thin alloy or by laminating short sheets thereof. The surface roughness of the thin alloy sheet or sheets is limited to lie within a predetermined range in order to improve the squareness ratio of the magnetic core. The magnetic core exhibits excellent squareness ratio characteristic and magnetic saturation characteristic in high-frequency regions.

Description

Magnetic core technology field

The present invention provides a saturable reactor used in a high-frequency switching power supply, which has excellent squareness characteristics and magnetic saturation characteristics particularly at high frequencies (specifically, 50 kHz or more) and also has low iron loss. The present invention relates to a magnetic core suitable for a magnetic component such as a reactor for a semiconductor circuit and an alloy thin film used for manufacturing the magnetic core.

Background technology

In recent years, with the demand for smaller and lighter electronic devices and higher performance, magnetic components used as important functional components also need to have higher performance. In particular, for switching power supplies used as power supplies for office automation equipment and communication equipment, higher frequencies are being studied due to the demand for smaller and lighter units. Therefore, magnetic materials used for these magnetic components are also required to have excellent high-frequency magnetic characteristics. In particular, a material having high magnetic permeability is effective for many magnetic components such as a current sensor such as a zero-phase current transformer and a noise filter.

In recent years, switching power supplies incorporating magnetic amplifiers have been widely used from the viewpoint of high reliability and high efficiency.

The main part of this magnetic amplifier is a saturable reactor. Therefore, there is a need for a magnetic core material having excellent square magnetization characteristics. Conventionally, as such a magnetic core material, Sen Delta (B¾ product name) made of Fe—Ni alloy has been used.

Sen-delta has excellent square magnetizing characteristics, but its coercive force increases at high frequencies of 20 KHz or more, increasing eddy current loss and generating heat, making it unusable. . For this reason, the switching frequency of a switching power supply incorporating a magnetic amplifier was limited to 20 kHz or less.

In recent years, along with the demand for downsizing and weight reduction of switching power supplies, it has been demanded that the switching frequency be increased to a lower frequency, and that the coercive force at high frequencies be small, and that the rectangular characteristics and thermal stability be reduced. Amorphous alloy has been studied as an excellent core material (see

No. 2 258 04).

However, in order to increase the efficiency of the switching power supply, it is essential to further improve the performance of the amorphous alloy core, especially the squareness ratio and the magnetic field in magnetic amplifiers used at frequencies above 50 kHz. Further improvement in saturation characteristics (for example, reduction of saturation inductance) was desired.

Disclosure of the invention

The present invention has been made in consideration of the above problems, In particular, it is an object of the present invention to provide a magnetic core using an alloy ribbon having a large square ratio in a high-frequency region and a small saturation inductance.

A magnetic core according to the present invention is a magnetic core formed by winding or laminating an alloy ribbon and having excellent square characteristics in a high-frequency region, and a concave portion on the surface of the thin film on the roll surface side. By reducing the area occupancy of the core to 30% or less, the squareness ratio of the magnetic core is improved.

By making the area occupancy of the concave portion on the roll-side surface of the alloy thin film 30% or less, the present inventors sharply improve the squareness ratio in a high frequency range and reduce the saturated inductance. Can be headed. Further, the present inventors have set the area occupancy of the surface recesses on the roll surface side of the alloy ribbon constituting the magnetic core to 30% or less, and at the same time, the surface roughness (R i) on one side of the fly to 0.3% or less. By doing so, it has been found that the square characteristics of the magnetic core, particularly in the high frequency region, can be improved. The present invention has been made based on the above findings.

According to the present invention, there is provided a magnetic core having a squareness ratio of 98% or more, preferably 98.5% or more, and more preferably 99% or more at a frequency of 100 kHz. Further, according to the present invention, it is possible to provide a magnetic core having a saturation magnetic property of 550 (G) or less, and further, 500 (G) or less. Here, the saturation magnetic properties are usually determined by the shape of the magnetic core, the number of turns, and Depends on fixed conditions. In the present invention, the evaluation criteria are as follows: (1) a magnetic core having an outer diameter of 15 mn, an inner diameter of 10 turns, and a height of 4.5 rara; (2) the number of windings is 1 turn; It is expressed as the difference between the magnetic flux density and the residual magnetic flux when a 16 (0e) magnetic field is applied at 100 kHz.

BRIEF DESCRIPTION OF THE FIGURES

1 and 2 are scanning electron micrographs showing the surface condition of the alloy ribbon in the present invention, and FIG. 3 is a graph showing the area occupancy, the squareness ratio, and the ratio of the concave portions formed on the surface of the alloy ribbon. FIG. 4 is a graph showing the relationship between the surface roughness and the squareness ratio, and FIG. 5 is a graph showing the relationship between the thickness of the alloy ribbon and the iron loss.

BEST MODE FOR CARRYING OUT THE INVENTION

In recent years, 钦 magnetic alloy ribbons used for magnetic core materials used at high frequencies have been increasingly manufactured by the so-called melt quenching method. In this method, a ribbon-shaped ribbon is obtained by injecting a molten alloy of a predetermined composition, which is melted in a heat-resistant container such as quartz, from a nozzle onto the rotating surface of a metal cooling roll that rotates at high speed and quenching it. Things. However, fine irregularities are formed on the surface of the alloy ribbon produced in this way (the rim surface, that is, the surface in contact with the cooling roll) inevitably. I have. According to the study of the present inventors, it is preferable that the area occupation ratio of the concave portion existing on the roll-side surface of the alloy ribbon be 30% or less. Strictly to 25% or less, and more preferably to 20% or less, it is possible to sharply improve the squareness ratio in the high frequency range and to reduce the saturation inductance. I found what I could do.

That is, in the magnetic core of the present invention according to the first aspect, the alloy melt is ejected from the nozzle to the surface of the cooling roll and rapidly cooled to produce an alloy ribbon, thereby producing an alloy ribbon. Further, the present invention is characterized in that the concave portion formed on the surface of the alloy ribbon on the side in contact with the cooling roll is formed of an alloy ribbon having an area occupancy of 3 °% or less.

Normally, when an alloy ribbon is manufactured by the above-described molten metal quenching method, the surface condition of the obtained alloy ribbon mainly depends on the surface condition of the cooling roll and the wettability between the molten alloy and the roll. Depend on. The wettability in this case is also affected by the composition of the alloy. The recess formed on the surface of the alloy ribbon is formed by air bubbles that are caught between the cooling roll and the molten metal.

As will be apparent from the results of the projecting examples described below, according to the present invention, the area occupancy of the concave portion formed on the alloy ribbon surface on the side in contact with the cooling roll is limited to 30% or less. This can significantly improve the squareness ratio of the magnetic core.

The effect of improving the squareness as described above is especially the Curie temperature This is remarkable in amorphous alloys with a temperature of less than 300 ° C. The reason is presumed to be the ratio of the magnitude of the shape magnetic anisotropy caused by the induced magnetic anisotropy generated by the heat treatment and the surface roughness. In other words, it is remarkable in alloys having a relatively low induced magnetic anisotropy with a temperature of 300 ° C or lower. As described above, the method of limiting the area occupancy of the concave portion formed on the ribbon surface to 30% or less is to improve the wettability between the cooling roll and the molten alloy and to optimize the cooling rate. No. Specific methods for this include the use of iron-based steel (for example, S45C, high-speed steel), and the use of cold for Cu-based alloys (CuBe, CuTi, etc.). There is a method of controlling the temperature of the water to be cooled from the inside of the cooling roll to 30 to 60 ° C, or a method of increasing the injection temperature of the molten alloy to 135 ° C or higher.

As a more preferable method, it is possible to reduce the generation of recesses (for example, 10% or less) by reducing the manufacturing atmosphere to a pressure lower than the atmospheric pressure.

The definition and measurement method of “the area occupancy of the concave portion formed on the surface of the thin layer” in the present invention are as follows.

Take a photograph of the roll surface at a magnification of 200 times with a scanning electron microscope at ffl. From this photograph, all the concave parts with a major field of view (the diameter of the smallest circle that wraps around and touches the concave part) are picked up and image processing equipment (for example, Japan Legray) The ratio of the area occupied by the recessed portion per basement area is calculated using the LUZEX 500 manufactured by K. I. At least: Perform 0 times, find the average value, and use this average value as “area occupancy”.

Next, a second mode for controlling the surface roughness of the alloy ribbon will be described.

That is, the second aspect of the present invention is to produce an alloy ribbon by injecting a molten alloy from a nozzle to the surface of a cooling hole and quenching the molten alloy. The surface roughness of the alloy ribbon surface is such that, in the longitudinal direction of the alloy ribbon,

R f ≤ 0.3

(However, R f is the average plate thickness obtained from the ten-point average roughness at the standard length of 2.5 ram specified in JIS B 0601 and the weight of the alloy ribbon. Then, the following formula:

R f = R z / T

This is a param which characterizes the roughness obtained by the above. The magnetic core is formed by an alloy ribbon having a certain value. This value of R f is preferably 0.25 or less, more preferably 0.22 or less. Normally, when manufacturing alloy ribbons by the molten metal quenching method, the yield is determined by conditions such as the surface condition of the cooling roll, and the stability of the molten steel pool formed between the nozzle and the roll. The surface condition of the alloy strip is affected. According to the study of the present inventors, irregularities (so-called fish scales) appearing periodically in the longitudinal direction of the ribbon, which are likely to occur particularly on the free surface (that is, the surface on the side not in contact with the cooling roll). However, it has been found that the high frequency magnetic properties of the alloy ribbon, particularly the squareness ratio, are adversely affected.

That is, by limiting the surface roughness in the longitudinal direction of the alloy ribbon to R f ^ 0.3, and more preferably to R f ≤0.27, in accordance with the above-mentioned rules, the high-frequency region can be obtained. It is possible to remarkably improve the squareness ratio and to reduce the saturation inductance.

Such an effect is remarkable especially when an amorphous alloy having a temperature of 300 ° C. or less is used as a material. The reason is presumed to be that the shape anisotropy caused by the surface roughness is involved, as described for the thin hole surface.

In order to control the surface roughness as described above, it is necessary to appropriately control production parameters such as the material of the cooling roll, the surface temperature of the roll, and the temperature of the molten metal at the time of injection. For that purpose, it is necessary to adjust and adjust the cooling speed and roll peripheral speed, for example. Specifically, it is effective to use a Cu-based alloy roll and set the water temperature inside the roll to 30 to 80, or to set the roll peripheral speed to 25 mZs or more. . Next, the alloy material used for the magnetic core of the present invention will be described.

In the present invention, a Co-based amorphous alloy or a Fe-based magnetic alloy can be used.

Here, the preferred composition of the C0-based amorphous alloy is represented by the general formula

^{_{^{① (C o l- a F e}}} a) 100-X (S -1 B l) x

Where 0.02 ≤ a ≤ 0.08

0.3 ≤ I ≤ 0.8

2 6 ≤ X ≤ 3 2

② (Ogi-(S

C ^o H) _-C ^{F e} b ^M c) y 1-m B _m ) y where M is at least one of N i and N n b ≤ 0.10

〇. 0 1 ≤ e ≤ 0. 1 0

0.3 ≤ ≤ 0.8

2 6 ≤ y ≤ 3 2

_{_{③ (C0 _ e F e d}} M 'e) 100 _ z (S i ^ B n) z provided that NT is T i, V, C r, C u, Z r, N b,

At least one selected from No, Hf, Ta, W,

0.03 ≤ d ≤ 0.10

0. 0 1 ≤ e ≤ Ό. 0 6

0.3 ≤ η ≤ 0.8

24 ≤ ≤ ≤ 3 2 〇

④ ( ^{C o} W-gh ^{F e} f ^M g ^M 'h) 100-V

^(Si to P ^B p) w

Where M is at least one of N i and M n

.f ≤ 0. 1 0

0.01 ≤ g≤ 0.10

0.0 1 ≤ h≤ 0.08

ϋ. 3≤ p ≤ 0.5

24≤ w≤ 3 0

One is either represented by both saturation magnetostriction constant ^ lambda s one 1 1 0 ^_6 ≤ scan s ^ lxi O within the scope of ^-6 C o group Amorufu § scan alloy favored arbitrariness of.

C o group Amorufu § scan alloy used in the magnetic core of the present invention is represented by the above SL four general formula, where the the most important, the set for setting the Curie temperature to below 3 0 0 ^e C This is the setting, and the atomic ratio between the metal element and the metalloid element is mainly used. In general formulas ① to X, X, y, z are 26 to 32,

The reason why w was set to 24 to 30 in (3) and (4) is that if X, y, and z are less than 26 or w is less than 24, the coercive force is large, the iron loss value is large, and the thermal stability is poor. On the other hand, if x, y, and z exceed 32 or W exceeds 3, the Curie temperature decreases and becomes impractical.

F e is the magnetostriction - an element for adjusting the 1 X 1 0 _ ⁶ ~ ten ^{1 X 1 0 _ 6, N} i, the addition amount of the additive amount or the non-magnetic transition metal element M n, and S i According to the value of the B ratio A, b, d, and f, which represent the mixing ratio with Co, respectively

0.02 to 0.08, 0.10 or less, 0.03 to

This can be achieved by specifying a value within the range of 0.10 and 0.10 or less.

M (at least one selected from Ni or Mn) and M '(Μ' are from Ti, V, Cr, Cu, Zr, Nb, Mo, Hf, Ta, W (At least one selected) is an element that is effective for further improving the thermal stability, but the added amounts c and h are 0.10 or less and ◦ .0'8 or less, respectively. If h is 0.10 or more and 0.08 or more, the curing temperature is too low, which is not preferable.

S i and B are essential components for making the alloy amorphous, but in order to obtain a magnetic core with low iron loss, high squareness ratio and high thermal stability, the combination of S i and B It is necessary to define 1, m, n or p, which indicates the compounding ratio, in the range of 0.3 to 0.5, and to obtain a Si rich. This is because, when the force is 1, m, n or p, which is less than 0.3 or more than 0.5, it is particularly difficult to obtain a high squareness ratio, and the thermal stability of the magnetic properties is slightly increased. is there.

Among the above alloy compositions (1) to (4), the alloys (3) and (4) are the most preferred from the viewpoint of reducing the depth of the recess by the inclusion of air bubbles (the first embodiment of the present invention). It is. More preferably, it is a case where Cr, Nb or Mo is selected as M '. This is due to improved wettability and It is probable that the viscosity was decreasing.

In both of the first and second aspects of the present invention, the effect of shape magnetic anisotropy is expressed by the relationship between the magnitude of induced magnetic anisotropy. Thus, in particular the 1 0 ⁴ erg / ec following materials magnitude of the induced magnetic anisotropy, the present invention is particularly effective. In addition, as described above, the present invention has a remarkable effect particularly in an amorphous alloy having a Curie temperature of 300 ° C. or lower. In, the squareness ratio and saturation inductance do not reach sufficiently good levels. Therefore, in the present invention, the Curie temperature range is preferably from 160 to 300 ° C, more preferably from 180 to 280 ° C, still more preferably from 190 to 270 ° C. It is.

Note that reducing the Curie temperature to 300 ° C. or less also means improving the thermal stability. In general amorphous alloys are known to be obtained by quenching with 1 0 ⁴ ° CZ seconds or more cooling rate of the alloy material having a predetermined composition ratio from a molten state (liquid quenching method). The amorphous alloy of the present invention can also be easily produced by the above-mentioned ordinary method. This amorphous alloy is used, for example, as a plate-shaped ribbon manufactured by a single roll method. In this case, if the thickness exceeds 25 i / m, iron loss at high frequencies increases, so it is preferable to set the thickness of the ribbon to a range of 5 to 25 m.

The magnetic core of the present invention comprises an amorph formed by the above manufacturing method. The force to wind the gas alloy into a predetermined shape and perform the heat treatment for strain relief (the cooling rate at that time is 5-50). CZmin. May be sufficient, preferably in the range of 1-20 / 111111. Further, heat treatment may be further performed in a magnetic field at a temperature equal to or lower than the temperature of the capacitor.

— On the other hand, in the present invention, an Fe-based ultrafine crystal alloy can be used. This alloy is? Add Cu and one of Nb, W, Ta, Zr, Hf, Ti, Mo, etc. to 6-5-8 alloy, etc., and then temporarily use the same ribbon as the amorphous alloy. And then heat-treated in a temperature range equal to or higher than the crystallization temperature to precipitate fine crystal grains.

The present invention can be similarly applied to the above-described Fe-based ultra-microcrystalline alloy.

The alloy composition used for producing the above-described Fe-based magnetic alloy ribbon is as follows.

—General formula:

^{F e} 100-efghij ^E e ^ f ^J g ^{S i} h ^B i ^Z j

…… (Π) (where E is at least one element selected from Cu and Au, and G is a group consisting of Wa group elements, Va group elements, Wa group elements and rare earth elements) J is at least one element selected from the group consisting of Mn, Al, G a, G e, In, Sn and a platinum group element. 4 one

, And Z represents at least one elemental rope selected from the group consisting of C, N, and P, and e, f, g, h, i, and j satisfy the following equation: It is the number to do. However, all numbers in the following formula represent at%.

0.1 ≤ e ≤ 8

0.1 ≤ f ≤ 1 0

0 ≤ g ≤ 1 0

1 2 ≤ h≤ 2 5 0≤} ≤ 1 0

Same as 1 5 ≤ h + i + j ≤ 30 _o . ) Are preferably used.

Here, E (Cu or Au) in the above formula (Π) is effective for improving corrosion resistance, preventing crystal grain coarsening, and improving magnetic properties such as iron loss and magnetic permeability. Element. In particular, it is effective for low-temperature precipitation of the bcc phase. If the amount is too small, the above-described effects cannot be obtained, while if it is too large, the magnetic properties deteriorate, which is not preferable. Therefore, the content of E is preferably in the range of 1 to 8 atomic%. The preferred range is 0.1 to 5 atomic% G

G (at least one element selected from Group IVa, Group Va, Group VIa, and rare earth elements) is effective for uniform crystal grain size, One Is an effective element for improving soft magnetic properties and improving magnetic properties against temperature change, and stabilizing the bcc phase over a wider temperature range by adding it with E (e.g., Cu). Can be. If the amount is too small, the above effect cannot be obtained. If the amount is too large, non-crystallization is not performed in the manufacturing process, and the saturation magnetic flux density further decreases. Therefore, the content of G is preferably in the range of 0.1 to: 0 atomic%. A more preferable range is 1 to 8 atomic%.

The effect of each element in E, together with the above effects, is the same as that for group IVa elements, such as expansion of heat treatment conditions for obtaining optimum magnetic properties, and group Va elements, such as improvement of brittleness resistance and cutting. Group VIa elements are effective in improving workability and corrosion resistance and surface properties.

Among them, Ta, Nb, W, and Mo are particularly preferable in that the magnetic properties are improved, and V has a remarkable effect of improving the surface properties as well as the embrittlement resistance.

J (at least L elements selected from Mn, Al, Ga, In, Sn and platinum group elements) is an element effective in improving magnetic properties or improving corrosion resistance. However, if the amount is too large, the saturation magnetic flux density decreases, so the content is set to 10 atomic% or less. Among them, A 1 is particularly effective in reducing crystal grain size, improving magnetic properties and stabilizing the bcc phase, Ge is effective in stabilizing the bcc phase, and platinum group elements are effective in improving corrosion resistance. Element.

Si and B are elements that help the alloy to be non-crystallized during manufacturing, can improve the crystallization temperature, and are effective elements for heat treatment for improving magnetic properties. In particular, Si is dissolved in Fe, which is a main component of fine crystal grains, and contributes to reduction of magnetostriction and magnetic anisotropy. If the amount is less than 12 atomic%, the improvement of the magnetic properties is not remarkable, and if it exceeds 25 atomic%, the super-quenching effect is small, and relatively large crystal grains at the m level are precipitated, and the good results are obtained. Soft magnetic properties cannot be obtained. Furthermore, S i is particularly preferably 12 to 22 at% due to the appearance of a superlattice. If B is less than 3 atomic%, relatively coarse crystal grains precipitate and good characteristics cannot be obtained. If it exceeds 12 atomic%, B compound is easily precipitated by heat treatment, and 钦 magnetic properties are deteriorated. Is not preferred.

Further, Z (C, N, P) may be contained as another amorphousizing element in a range of 10 atomic% or less.

The total amount of S i and B and the other amorphizing elements is preferably in the range of 15 to 30 atomic%, and when S i / B ≥ 1, excellent magnetic properties can be obtained. I like it.

In particular, by setting the Si content to 13 to 21 at%, magnetostriction; I s 0 is obtained, and the deterioration of the magnetic characteristics due to the resin mold is eliminated, and the desired magnetic characteristics are effective. It is possible to make the most of it.

In the above Fe-based magnetic alloy, 0, S, etc. The effect of the present invention is not impaired even if a trace amount of unavoidable impurities such as those contained in ordinary Fe-based alloys is included. Hereinafter, embodiments of the present invention will be described.

Example A 1 and Comparative Example ^{^{A 1 (0.900 1 e 0.05 N}} b 0.05 ^ r 0.02 y 75

^{(S 1} 0.56 ^B 0.44) 25

Using the single-roll method, long ribbon samples a and b of 16 mm in thickness and l O ram in the form of a ribbon with different surface properties were prepared for the amorphous alloy represented by .

When the entrapment of air bubbles on the roll surface of the samples a and b was observed by a photograph, differences as shown in FIGS. 1 and 2 were observed. The percentage is 38% for sample a (Fig. 1) and 23% for sample b (Fig. 2).

The measurement of the area occupancy of the recess was performed as follows. First, a photograph was taken at a magnification of 200 times using a scanning electron microscope on the roll surface of the ribbon. Field of view in this photo

Within the range of 0.45 ram X 0.55, a concave part with a major axis of 1 ◦ ^ m or more was extracted, and image processing was performed to determine the area. This was compared with the entire viewing area to determine the area occupancy of the recess. Outside diameter by turning the obtained winding the thin alloy strip 1 8ra _m, were molded inner diameter 1 2 thigh toroidal core. Next, this is heat-treated at an appropriate temperature not lower than the Curie temperature and not higher than the crystallization temperature. C

/ min. Cooled. Primary and secondary windings are applied to the obtained core, an external magnetic field of 10 e is applied, and an AC hysteresis curve is measured using an AC magnetization measuring device, and the squareness ratio B r 1 (B r : Residual magnetic flux density, B 1 _: magnetic flux density in a magnetic field of 10 e). The value at 1 ◦ 0 KHz was 99.4% for the magnetic core using the material shown in Fig. 1, and 94.8% for the material shown in Fig. 2, which was a difference of about 5%.

When these cores were applied as a saturable reactor in a power supply with a switching frequency of 1 OOKHz, the core of the present example using the ribbon of FIG. 1 was compared with the comparative core using the ribbon of FIG. In comparison, the output uncontrollable range (dead andal) was smaller, and the efficiency was improved by about 2%.

Example A 2

By the single roll method (C 0 F e M n

0.90 0.05 0.02

Various amorphous alloys having the composition of N b _{0 03} ) ₇₅ S i _1δ Β ₁₂ were prepared to have various surface properties.

These materials were used as magnetic cores in the same manner as in Example A1, and the relationship with the squareness ratio at high frequencies was examined. The results are summarized in Fig. 3, and it can be seen that the squareness ratio sharply deteriorates at an area occupancy of 30%.

In the following Examples and Comparative Examples, the area occupancy of the concave portion on the roll surface was measured in the same manner as in Example A1. Example B 1 and Comparative Example B 2

For Amorufasu alloy represented by ^{^{^{(C ° 0.94 F e 0.05 Nb}}} 0.01) 71 (S 0.6 B 0.4} 29, the plate thickness iota [delta] [pi, different surface properties in thin strip shape having a width 1 0 mm by a single roll method Long ribbon samples a and b were prepared.

The results of measurements of samples a and b in the longitudinal direction of the ribbon using a surface roughness meter were expressed as R f, respectively, of 0.15 and

It is 0.38. This was wound to form a toroidal core having an outer diameter of 18 ram and an inner diameter of 12 ram. Next, this was heat-treated at an appropriate temperature not lower than the Curie temperature and not higher than the crystallization temperature, and then cooled at a rate of 4 min.

Primary and secondary windings are applied to the obtained core, an external magnetic field of 10 e is applied, and an AC hysteresis curve is measured using an AC magnetometer, and the squareness ratio Br ZB 1 (B r: Residual flux density, B 1: Obtain 10 e. Magnetic flux density in magnetic field)

The value at 50 KHz was 99.4% for a magnetic core made of a material with R f = ◦.15, and 94.8% for a core with R f = 0.38, giving a difference of about 5%. .

When these cores were applied as a saturable reactor in a power supply with a switching frequency of 1◦◦ KHz, the core of the present example using a ribbon with R f 0.15 provided R f = 〇. No output control compared to the comparative core using 38 ribbons Noh 4 (dead angle) is small, and efficiency is improved by about 2%.

Example B 2

_{_{(C o 0 90 F e 0}} . 05 M n () 02 N b 0) 71 were different were prepared to have a S i _lc various surface properties of amorphous alloy B with a composition by a single roll method.

These materials were used as magnetic cores in the same manner as in Example B1, and the relationship with the squareness ratio at a frequency of 100 kHz was examined. The results are summarized in Fig. 4. It is clear from R f = 0.3 that the squareness ratio deteriorates rapidly.

Example C 1 and Comparative Example C 1

F e _{? 4} C u ₁ N b. An amorphous alloy having an alloy composition of S _lg B _g was prepared by the il roll method as a thin ribbon having a surface property of 22% and 40% of the concave portion of the roll surface. This, 1 8 stroke X 1 2 transliteration X 4. 5 mm bets, after forming a toroidal shaped core, 1 hour at 560, were heat-treated in an N ₂ atmosphere. 400 after this. Magnetic field heat treatment was performed at 5 (0 e) for 2 hours at C.

In the same manner as in Example A1, the squareness ratio in {} was measured. The magnetic core of the present invention had a squareness ratio of 98.7%, and the comparative example had a ratio of 94.5%.

As a result of applying these cores as saturable reactors in a power supply with a switching frequency of Ι Ο Ο 、, the core of the embodiment has a lower output control than the core of the comparative example. Power (dead angle) is small, and power supply efficiency has been improved by about 2%.

Example A 3 and Comparative Example A 3-( ^{C 0} 0.90 ^xe 0.05 ^M ° 0.03 ^{C r} 0.02 ^y 75, ^{S 1} 0.6

For Amorufu § scan alloy represented by B _{0 4)} _25, by changing the manufacturing conditions by a single roll method to produce a thin strip having various thickness and surface properties. These ribbons were wound on a toroidal core with an outer diameter of 18 mm and an inner diameter of 12 rara, and were subjected to strain relief heat treatment at 440 ° C for 30 minutes, and then at 20 CTC for 2 hours at 5 (0e). Magnetic field heat treatment was performed under the conditions. The resulting core was evaluated in the same manner as in Example A1, and the squareness ratio at 100 KHz and the iron loss at 100 KHz and 2 KG were evaluated. The sheet thickness t was determined as an average sheet thickness by a gravimetric method. The average plate thickness t in this case can be obtained by the following equation when length 1, width w, weight A, and density p are set.

t = A / (I + w + p) The results are shown in Table 1. It is found that the core using the material having the surface property of the present invention has excellent squareness ratio and low iron loss.

The iron loss of 100 KHz was measured for various plate thicknesses with a surface roughness R f of 0.2 and 0.38. The value increases monotonically with increasing plate thickness regardless of the surface properties. R ftm) Br / Bl (%) P _2KG / lOOKHz

0.22 21.0 99.5 350

0.34 18.5 96.4 340

0.24 28.4 99.0 560

0.36 28.0 97.0 520 Example A 4 and Comparative Example A 4

By the single roll method, (Co _{0 90} Fe _{0 05} Cr _0> ) _{? 3}

The _{_{(S i Λ 5 cB 0>}} 45) Amorufu § scan alloy represented by ₂₇ and two produced. The thickness is 19 / m and the width is 5 mm. By changing the material of the roll used and the temperature of the roll cooling water, for one type, the concave portion on the roll surface was 22%.

35%, surface roughness on the free side 0.25 and

It was 0.35. These strips were punched out into a ring-shaped core with an outer diameter of 8 rom and an inner diameter of 6 mm by photoetching, 430. C-

Heat treatment for strain relief for 40 minutes, then at 200 ° 0 for 1 hour,

The magnetic core was subjected to a magnetic field heat treatment under the condition of 2 (0 e) and laminated so that the height became 5ιηιη.

When the squareness ratio at 100 kHz was measured in the same manner as in Example A1, the core of the present invention was 99.1%, and the core of the comparative example was 95.2%.

These cores are connected to a switching frequency of 200 kHz. When used as a saturable reactor, the core of the present invention had better output control characteristics and improved power supply efficiency by 2.5% compared to the comparative example.

Example A5 or A20, C2 to C15, Comparative Example

5, 8, 6, 7, 2 3

A 5 mm-wide ribbon was produced by the single roll method according to the composition and production conditions shown in Table 2. The Curie temperature of the Co-based amorphous alloy was also measured. Each ribbon was wound around an outer diameter of 15 leaks and an inner diameter of 10 ram toroidal core. Each of the obtained C 0 -based amorphous cores was subjected to a strain-relieving heat treatment at the optimum temperature for 30 minutes, and then a magnetic field of 1 (O e) was reduced for 2 hours at a temperature not higher than the Curie temperature of 3 CTC. A magnetic field heat treatment was performed by applying a voltage in the band longitudinal direction. Also, since that is a Amorufasu state in a quench condition for F e based alloy, each of the crystallization temperature. 50 (value measured at a Atsushi Nobori condition 1 0 ^e CZ min using a differential scanning calorimeter) After heat treatment at a temperature on C for 1 hour, a magnetic field heat treatment was performed by applying a magnetic field of 5 (O e) in the longitudinal direction of the ribbon at 450 for 1 hour. All heat treatments were performed in a nitrogen atmosphere.

The obtained magnetic core was evaluated for squareness at 100 kHz and iron loss at 100 kHz and 2 kHz in the same manner as in Example A1. The results are shown in Table 2, which shows that the magnetic core of the present invention has an excellent squareness ratio. In these examples, the value corresponding to the saturation inductance is - twenty four - -·.-,

And the magnetic flux density was determined. The magnetic flux density was determined from the difference between the magnetic flux density and the residual magnetic flux density under the condition that a magnetic field of 16 (0 e) was applied at a frequency of 100 kHz and the number of turns of the core was 1 °.

/ soedf / JDd 16 OM

in

Z Halla

Industrial applicability

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide a winding core having an excellent output control characteristic having high squareness, and is widely applied particularly to magnetic components of a switching power supply, such as a magnetic amplifier and a semiconductor circuit reactor. can do.

Claims

Range of request

1. A magnetic core formed by winding or laminating an alloy ribbon, and having a surface roughness such that an area occupancy of a concave portion formed on the surface of the alloy ribbon is 30% or less. A magnetic core characterized by being formed by a band.

2. The magnetic core according to claim 1, wherein the alloy ribbon is a Co-based amorphous alloy ribbon.

3. The magnetic core according to claim 2, wherein the alloy ribbon is made of a C0-based amorphous alloy having a temperature of 16 ° C: 3 ° C.

4. The magnetic core according to claim 1, wherein the squareness ratio is 98% or more at a frequency of 50 KHz.

5. The alloy ribbon is manufactured by injecting the molten alloy from the nozzle onto the surface of the cooling roll and quenching it, and the surface roughness of the alloy ribbon that does not come into contact with the cooling roll has the following value. In the longitudinal direction of the alloy ribbon,

R f ^ 0. 3

(However, R f is defined by JI $ — B — 0601. • The average plate thickness obtained from the ten-point average roughness at the S semi-length of 2.5 mm and the weight of the alloy ribbon is When R z and T respectively,

R f = R z / T

Is a parameter characterizing the roughness obtained by the above. ) The magnetic core according to claim 1, wherein the magnetic core is formed by an alloy ribbon having a value.

6. The magnetic core according to claim 5, wherein the alloy ribbon is a Co-based amorphous alloy ribbon.

7. The magnetic core according to claim 5, wherein the alloy ribbon is made of a Co-based amorphous alloy having a Curie temperature of 16 to 300.

8. The magnetic core according to claim 5, wherein the squareness ratio is 98% or more at a frequency of 50 KHz.

9. The magnetic core according to claim 1, wherein the alloy ribbon is made of a Co-based amorphous alloy ribbon having an alloy composition represented by the following general formula.

^(C ° 1-a ^{F e} a) 100-X ^{(S i} 1-1 ^B 1) x

(However, 0.02 ≤ a ≤ 0.08

0.3 ≤ I ≤ 0. S

26≤ X≤ 32 o)

10. The magnetic core according to claim 1, wherein the alloy ribbon is a Co-based amorphous alloy ribbon having an alloy composition represented by the following general formula. C ° 1-bc ^{F e} b ^M c 100-y ( ^S 1 ^B m) y (where M is at least one of N i and N n

b ≤ 0.10

0.01 ≤ e ≤ 0.10

0.3 ≤ m≤ ϋ. 8

26≤ y≤32. )

1 1. The magnetic core according to claim 1, wherein the alloy ribbon is a C0-based amorphous alloy ribbon having an alloy composition represented by the following general formula.

(Co 1,-) d-one e Fe d ^ M 'e 100--z, (s 1-n n z

(Where M ′ is at least one selected from the group consisting of Ti, V, CCu, Zr, Nb, No, Hf, Ta, W,

0.03≤ d≤ 0.10

0.0 1≤ e≤ 0.06

0.3 ≤ n ^ 0.8

24≤ z≤32. )

12. The magnetic core according to claim 1, wherein the alloy ribbon is a Co-based amorphous alloy ribbon having an alloy composition represented by the following general formula.

^{(C o} lfgh Fe _f MgM ' _h ) _i00 _ _w (Sin B _{p) w} (where M is at least one of _Ni and M n and f ≤ 0.10

0.0 1 ≤ g ≤ 0.1 0

0.0 1 ≤ h≤ 0.08

〇. 3≤ p≤ 0.5

24≤ w≤ 3〇. )

1 The alloy ribbon is an alloy represented by the following general formula 20

-30-

The magnetic core according to claim 1, comprising a Fe-based magnetic alloy ribbon having a composition.

F ^e 100-efghij ^E e ^ f ^J g ° h ^B i ^Z j

(Where E is at least one element selected from Cu and Au, and G is at least one element selected from the group consisting of group IVa elements, group Va elements, group Wa elements and rare earth elements. J is at least one element selected from the group consisting of Mn, Al, G a, G e, In, Sn, and platinum group elements, and Z is C, N And at least one element selected from ^ consisting of P and e, f, g, h, i, and j are numbers that satisfy the following formula, provided that all numbers in the following formula Indicates at%.

0. 1≤ e≤ 8 0≤ g≤ 1 0

1 2≤ h≤ 25

3≤ i ≤ 12

0≤j≤1 0

1 5 ≤ h + i + j ≤ 30. )

14. An alloy ribbon having a surface roughness such that an area occupation ratio of a concave portion formed on the surface of the alloy ribbon on the side in contact with the cooling roll is 30% or less.

1 5. The surface roughness of the alloy thin surface that does not contact the chill roll is in the longitudinal direction of the alloy thin strip. R f ≤ 0.3

(However, R f is the average plate thickness obtained from the ten-point average roughness at a reference length of 2.5 mm specified in JIS B 0601 and the weight of the alloy ribbon, Rz and T, respectively. When the following formula

R f = R z / T

It is a param night that characterizes the roughness obtained by. The alloy according to claim 14, characterized in that it has the following values:

16. The magnetic core according to claim 13, wherein the squareness ratio is 96% or more at a frequency of 100 kHz.