JPS5985846A - Amorphous alloy with small loss and high frequency transformer, choke coil, noise filter, step-up transformer and saturable reactor using said alloy - Google Patents

Abstract

PURPOSE:To reduce the iron loss in a high frequency region and to improve the thermal stability by adding Fe, Si, B and Ti, V, Mn, Y or Zr in ratios represented by a specified compositional formula. CONSTITUTION:An alloy represented by a formula (Fe1-xMx)zSiyB100-y-z (where M is one or more among Ti, V, Mn, Y, Zr, Mo, Hf, Ta, W and a rare earth metal, x is 0.005-0.1, y is 3-8, z is 80-85, and x+y+z=100) is refined. A high frequency transformer, a choke coil, a noise filter, a step-up transformer and a saturable reactor are obtd. using a core material made of the alloy. They have small iron loss at high frequency and improved thermal stability.

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention relates to a low-loss amorphous alloy that is effective for use in the magnetic core of electromagnetic devices, and more specifically relates to magnetic properties that reduce iron loss and improve thermal stability in the high frequency region. This invention relates to a low-loss amorphous alloy suitable for high-frequency magnetic cores such as switching regulators.

(Technical Background of the Invention and Problems thereof) Conventionally, crystalline materials such as permalloy ferrite have been used as magnetic cores used in switching regulators.

However, since permalloy has a low resistivity, iron loss at high frequencies increases. Further, although ferrite has a small loss at high frequencies, its magnetic flux density is as low as 5000G at most, and therefore, when used at a large operating magnetic flux density, it approaches saturation and as a result, iron loss increases. Recently, there has been a desire to reduce the size of transformers used at high frequencies, such as power transformers used in switching regulators, but in this case, the operating magnetic flux density must be increased, so the iron loss of ferrite is reduced. The increase poses a big problem in practice.

On the other hand, amorphous magnetic alloys that do not have a 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 have p t ,
Based on Qo, Ni, etc., P, O, B, 8i, AAt are added as amorphous elements (metalloids).
, Gg, etc.

However, not all of these amorphous magnetic alloys have small iron loss in the high frequency range.

For example, PM-based amorphous alloys exhibit a very small iron loss of about 1/4 of silicon steel in the low frequency range of 50 to 60 H2, but significantly large iron loss in the high frequency range of 10 to 50 KH2. However, it is not suitable for use in high frequency areas such as switching regulators.

In addition, with conventional pg-based amorphous alloys, in order to obtain low loss, it is necessary to heat-treat the alloy in a magnetic field, which complicates the processing process, resulting in manufacturing complications. Due to its low crystallization temperature, it also lacks thermal stability.

The inventor has been working on F-based amorphous alloys, and as a result of various studies focusing on improving iron loss, he has found that the amount of St in metalloid has a particularly large effect on high-frequency iron loss, and that this effect is even stronger in metalloid. It was found that this is due to a synergistic effect with the total amount.

(Objective of the Invention) An object of the present invention is to provide an amorphous alloy having magnetic properties that reduce iron loss and improve thermal stability in a high frequency region.

(Summary of the Invention) The uninvented amorphous alloy has the following formula'(" s −x M,
z) zS'y Bloo-y-z (in the formula, M is Ti, V
, MrL, Y.

Represents one or more rare earth metals such as Zr, Mo, Hf, Ta, and W, and x, y, and z are each 0.005 < x
<0.10, 3<y<s, 8 Q<;:z<85
.

Represents a number that satisfies the relationship z+y+z=100. ).

In the amorphous alloy of the present invention, M is an effective element for increasing the crystallization temperature, but if X exceeds 0.1, the saturation magnetization becomes small and it becomes impractical. Although Si is an effective element for increasing the crystallization temperature, if it exceeds the range of the present invention, high frequency core loss increases. The total amount of transition metals 2 has a significant correlation with iron loss, and when 2 exceeds the range of the present invention, high frequency iron loss increases.

The amorphous alloy of the present invention is produced by mixing the above-mentioned components in a predetermined ratio, melting the mixture, forming it into an amorphous alloy by a conventional method (for example, molten metal quenching method), and then melting it into an amorphous alloy in the absence of a magnetic field.
It can be easily produced by heat treatment in a temperature range of 500°C.

(Example of the invention) The present invention will be explained below based on examples.

Composition ("0.95"'0.05) 82 St Blg
Amorphous alloys with various values of y were produced by rolling and quenching. That is, a molten alloy having the above composition is heated between two high-speed rotating rolls through a quartz tube nozzle under argon gas pressure (1,
0 to 2.0#/m), and the obtained thin body was rapidly cooled to prepare a ribbon sample having a width of 2 vrx, a thickness of 30 μm, and a length of 10771 mm. A length of 100 CrrL was cut from this sample, which was wound around an alumina bobbin with a diameter of 20 mm, and then the whole was heat-treated at 430° C. for 10 minutes in the absence of a magnetic field. The primary and secondary coils are added to this, and the number of turns is 70.
times), magnetic flux density B m = 3KG iron loss (mW/
ω) was measured using a wattmeter at a frequency of 50 KHz.

The results are not shown in FIG.

As is clear from FIG. 1, when y representing the amount of 8i is 3 to 8, the iron loss becomes significantly small.

Next, the composition (F'0.94M'0.06) 828'6B
The alloy of the present invention consisting of +2 was used in a high frequency transformer. That is, by assembling this alloy into the EH11 type as a core material,
When operated at a frequency of 50 KHz and a magnetic flux density f3m=3 KG, the core loss was 500 m W/cr/I. For comparison (F'0.94M'0.06
) When an alloy consisting of 825i9B9 was used, the core loss was 900 mW/cr/l.

Furthermore, the core loss of something made of ferrite is 1000.
Large cutter with mW/crd.

Next, the composition (F'0.94T"0.06) 828'6B
The alloy of the present invention consisting of No. 12 was used for a choke coil. That is, using this alloy as a core material, EH11 type, 200μH
Assembled into a choke coil, frequency 100 KHz,
When operated as an output choke for a 50W switching power supply, the temperature rise was only about 30°C. For comparison, (F'o, s4'l'o, os) a□
When using an alloy consisting of 5t9B9, the temperature rise was approximately 8
The temperature was as high as 0°C.

Next, the composition (F'0.94W"0.06) 82S'6B
The alloy of the present invention consisting of No. 12 was used in a noise filter. That is, using this alloy as a core material, the outer diameter is 30 mg and the inner diameter is 2.
It was assembled into a toroidal core with a diameter of 10 mm and a thickness of 10 mm, and was operated as an input filter for a switching power supply. Note that the inductance is 2 mH3, resulting in an average noise attenuation rate of about 8 dB more than that of a conventional ferrite structure.

Next, the composition (F'0.94W0.06) 82St6B1
The alloy of the present invention consisting of No. 2 was used in a step-up transformer. That is, using this alloy as a core material, the outer diameter is 307I+IIl and the inner diameter is 2.
Assemble into a toroidal core of 0+m, thickness 10,
It was operated as a step-up transformer for a type cartridge. As a result, the third harmonic distortion at 20 Hz input was as small as about 0.5%. For comparison, conventional PC
When C part 0 alloy is used, the same strain as above is about 2%.
However, it was considerably larger than the one of the present invention.

Next, the composition (F'0.94T"0.06) 828'6B
The alloy of the present invention consisting of +2 was used in a Machinasawa reactor.

In other words, using this alloy as a core material, the outer diameter is 30 mm and the inner diameter is 5 mm.
It was assembled into a toroidal core of 20 tnvt and 10 mm thick and operated as a saturable reactor of a switching power supply with a frequency of 50 KHz and 100 W. As a result, the temperature rise in the core under full load was about 20°C. On the other hand, when a prismatic hysteresis alloy of 50 N i -F e was used for comparison, the temperature rise in the core was approximately 60°C.
It was a big thing.

(Effects of the Invention) As described above, the amorphous alloy of the present invention has significantly superior iron loss at high frequencies, and since it is a material mainly made of iron, it is inexpensive and compact when used in various applications. It is industrially useful because it allows for

It is a graph showing the Si dependence of iron loss of gold at 50 kHz and 3 kG.

Representative Patent Attorney Noriyuki Chika (1 idiot) Figure 11

Claims (1)

[Claims] lll (F't -x Mx)z S' Bt
oo −y−zM=Ti, ■*MnrY+”lrrMo
, Hf*Ta. W One or more rare earth metals 0.005 x x 0.10 3 < y x 8 80 x 85 x 10 y + z = i o. A low-loss amorphous alloy characterized by consisting of. (21(F'+-xMr)z S'yB1oo -y
-zM=Ti, V, Mn, Y, Zr, MO, Hf, Ta
. The core material is a low-loss amorphous alloy consisting of one or more of W rare earth metals, OOs<x<o, 10 3kuyku8 80kuzku85, High frequency transformer used as (at (Fgl-x M, T)Z S' Bt
oo-y-zM=Ti, V, Mn, Y, 'lr, Mo,
Hf, Ta. W One or more rare earth metals 0.005<2<0.10 3 <y < 8 80 x 85 x+y+z=1o. A choke coil that uses a low-loss amorphous alloy as the core material. (41(Fgl z M,)zSzy B100 y
zM=Ti, V, Ma, Y, Zr, MO, Hf, Ta. A noise filter using a low-loss amorphous alloy consisting of one or more W rare earth metals as a core material. +51 (F't x Mjc)z 8Ly B1
00 y zM=Ti, V, Mn, Y, Zr, Mo, H
f, Ta. A step-up transformer using a low-loss amorphous alloy as a core material consisting of one or more W rare earth metals 0.005 (Z-<0.10 3x8 80x85 x+3++2=1o. 16 ) (F'l-x M,y)z S'y Bt
oo-y-zM=Ti, V, Mn, Y, Zr, Mo,
Hf', Ta. A low-loss amorphous alloy consisting of one or more W rare earth metals 0, 005 saturation reactor.