JPH0798986B2 - Co-based amorphous magnetic alloy for high frequency switching circuits - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an amorphous magnetic alloy used in a high frequency switching circuit such as a voltage resonance type equipped with a magnetic amplifier using a saturable reactor.

[0002]

2. Description of the Related Art As is well known, stabilized power supplies for peripheral equipment of electronic computers and general communication equipment require small voltage and large current as specifications, but in recent years they have been called compact, lightweight and highly efficient for such applications. Switching type power supplies, which have advantages, are often used. A switching power supply using a voltage or current resonance waveform has advantages such as high switching efficiency of main switching elements such as transistors and thyristors, and low noise operation. However, there are drawbacks such as a narrow range of output power that can be controlled while holding the resonance waveform. As a typical one of the conventional switching circuits using the resonance waveform,
Particularly in the single-ended switching circuit, there is a quasi-E class switching circuit. This is a device in which an external circuit is devised so that the terminal voltage waveform of the switching element draws an arc of resonance. In that case, it is necessary to set the switching period, the conduction width, and the external circuit constant to predetermined conditions. The power conversion efficiency of the quasi-class E switching circuit using this voltage resonance waveform is 90% or more at an operating frequency of 100 KHz.

On the other hand, in the half-bridge switching circuit, the peripheral circuit is devised so that the waveform of the current flowing through the switching element draws an arc of resonance. A switching circuit using the resonance waveform of this current is effective because the commutation circuit can be omitted when the switching element is a thyristor. However,
In the above resonance type switching circuit, the resonance frequency is determined by the combination of the element values of the external circuit. Therefore, when the switching circuit using the resonance waveform is applied to the stabilized power supply or the power amplifier, it becomes complicated to control the output power. For example, in a normal forward type switch circuit, power can be easily controlled by simply changing the conduction width of switching, whereas in a switch circuit using a resonance waveform, the conduction width must be changed and the switching cycle must also be changed in a predetermined relationship. For example, power control cannot be performed while maintaining the resonance waveform. That is, when the conduction width is increased to increase the output power, the axis of the resonance arc is constant, and as a result, the switching cycle also needs to be lengthened. Therefore, the control configuration becomes complicated. Further, even if the complicated control circuit can be made to control the output power, the variable range is narrow, and it is insufficient to form a stabilized power supply or a power amplifier.

As one method of solving the above-mentioned drawback, there is a method of using a voltage-controlled magnetic amplifier in the output circuit. The main part that constitutes this magnetic amplifier is the saturable reactor, and it goes without saying that the squareness of the hysteresis curve related to the magnetism of the iron core of the saturable reactor influences the properties of the magnetic amplifier. Usually, a rectangular shape with a squareness ratio of 90% is used. However, if a permalloy having a squareness ratio of about 85 to 95% is applied as it is to a high frequency switch circuit of about 100 KHz, heat is generated due to eddy current loss and the function of the magnetic amplifier is impaired.

[0005]

In view of the above points, the present invention is a high frequency switching circuit having a magnetic amplifier which uses a saturable reactor and operates stably with high efficiency even at high frequencies, and has a good switching characteristic in a high frequency region. The present invention aims to provide a Co-based amorphous magnetic alloy for use.

[0006]

The present invention provides a Co-based amorphous magnetic alloy for a high-frequency switching circuit, which is equipped with a magnetic amplifier using a saturable reactor, in an atomic percentage of (Co _{1 -abc} Fe _a Ni _b M _c ) _1-d X _d 0.04 ≤ a ≤ 0.15 0 ≤ b ≤ 0.10 0.005 ≤ c ≤ 0.10 0.15 ≤ d ≤ 0.30 M is selected from Nb, Cr, Mo, V, Ta, Ti, Zr and W. At least one element X is B or B + Si. However, when Si is contained, the Si content is 25 atomic% or less, and at 20 to 100 KHz, B _r / B ₁₀ of the magnetic hysteresis curve is 85% or more, and the coercive force H _It is a Co-based amorphous magnetic alloy for high-frequency switching circuits characterized in that _c has a characteristic of 0.35 Oe or less.

The present invention is based on the discovery of high frequency characteristics of amorphous alloys. That is, it was found that even in the low frequency region, even though it is not superior to other materials, it exhibits remarkably excellent magnetic characteristics in the high frequency region. The present invention realizes effects such as improvement in efficiency and power efficiency. The reasons for limiting the composition of the amorphous alloy used in the present invention will be described in detail below. As described above, the amorphous magnetic alloy used in the present invention is (Co _1-abc Fe _a Ni _b M _c ) _1-d X _d 0.04 ≦ a ≦ 0.15 0 ≦ b ≦ 0.10 0.005 ≦ c = 0.10 0.15 ≦ d ≦ 0.30 M is at least one element selected from Nb, Cr, Mo, V, Ta, Ti, Zr and W X is B or B + Si However, when Si is contained, the amount of Si is 25 atomic% or less, Further, it is a Co-based amorphous magnetic alloy having properties such that B _r / B ₁₀ of the magnetic hysteresis curve is 85% or more and coercive force H _c is 0.35 Oe or less at 20 to 100 KHz.

It is well known that magnetic characteristics include direct current characteristics and alternating current characteristics (high frequency characteristics), and it has been known that heat treatment in a magnetic field is effective for improving the squareness ratio of an amorphous magnetic alloy. However, this is related to the direct current characteristics, and the magnetic characteristics in the high frequency region of the amorphous magnetic alloy that realized a high squareness ratio by heat treatment in a magnetic field have a high squareness ratio, but the hysteresis loop is distorted and the coercive force becomes large. Therefore, the loss is large and cannot be practically used. This tendency is particularly remarkable in the case of Fe-based amorphous magnetic alloy. The inventors of the present application proceeded with research to realize improvement of AC characteristics, particularly magnetic characteristics in a high frequency region, without heat treatment in a magnetic field. As a result, in a Co-based amorphous magnetic alloy, when a magnetic field was not applied during heat treatment, the direct current characteristics were inferior to those in the magnetic field heat treatment, but the characteristics were reversed in the high frequency region,
It has been found that very good magnetic properties, that is, high squareness and low coercive force can be realized.

Fe is an essential element for achieving high squareness and low coercive force, and its content a is limited to the range of 0.04≤a≤0.15. When a <0.04, the effect of adding Fe does not appear, and when a> 0.15, the squareness and the coercive force characteristic deteriorate rather.

Addition of a small amount of Ni adjusts the Curie point,
Although it is effective for improving the magnetic properties, excessive Ni addition may cause problems such as a decrease in saturation magnetic flux density and a decrease in Curie point. Therefore, the Ni content b is set to b ≦ 0.10.

Nb, Cr, Mo, V, Ta, Ti, Z
M, which is at least one element selected from r and W, is an element effective for improving magnetic properties such as low coercive force in a high frequency region, and is essential for realizing high squareness and low coercive force with good manufacturability. It is an element. The content c is 0.005 ≤
c ≦ 0.10. If it is too small, the effect of adding the M element is difficult to appear, and excessive addition causes an increase in the coercive force in the high frequency region.
This range is set because the magnetic properties in the high frequency region such as the decrease of the squareness ratio are deteriorated, and the brittleness becomes more difficult to handle.

Next, X (B or B + Si) is an element necessary for obtaining an amorphous alloy. The content d is 0.15 ≦ d ≦ 0.30. Outside this range, not only is it difficult to amorphize, but it is also difficult to obtain the effect of improving the magnetic characteristics in the high frequency region. Further, since excessive addition of Si causes deterioration of magnetic properties, it is set to 25 atom% or less of the whole.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 11 is a DC power supply, and the positive electrode of the power supply 11 is connected to the switching element, for example, the collector of the transistor 12, which is the transistor 12.
A switching pulse P having a predetermined conduction width and a predetermined conduction width is supplied to the base of, and thereby the opening and closing operation is periodically performed.
The emitter of the transistor 12 is connected to the negative terminal of the power source 11 via the primary winding 13 ₁ of the transformer 13.
A resonance capacitor 14 is connected in parallel to the primary winding 13 ₁ of the transformer 13, and a damper diode 15 is connected between the collector and the emitter of the transistor 12 with the polarity shown in the figure. The transistor 12, the transformer 13, the resonance capacitor 14, and the damper diode 15 form a single-ended switching circuit 16.

On the other hand, the secondary winding 13 ₂ , of the transformer 13,
One end of a saturable reactor 17 is connected to one end of 13 ₂ (the winding ratio of the primary winding and the secondary winding is n: 1) via a coil 13 _3, and the other end of the reactor 17 is a recirculation. It is connected to the cathode of the diode 18. The anode of the diode 18 is connected to the other end of the secondary winding 13 ₂ via the variable resistor 19. These secondary winding 13 ₂ and coil 1
3 ₃ , the saturable reactor 17, the freewheeling diode 12, and the variable resistor 19 are voltage controlled magnetic amplifiers 20 called Remy type.
Are configured.

The anode of a rectifying diode 21 is connected to the other end of the saturable reactor 17, and the cathode of the diode 21 is connected to the transformer 1 via a load 22.
3 is connected to the other end of the secondary winding 13 ₂ . This load 2
A smoothing capacitor 23 is connected in parallel to the capacitor 2, and the capacitor 23 and the diode 21 form a smoothing circuit 24.

The single-ended switching circuit 16 operates so that the voltage applied across the transistor 12 becomes an arc of a sine wave, the switching period and conduction width of the transistor 12, the capacitance value of the resonance capacitor 14, Values such as the exciting inductance of the transformer 12 are mutually determined. Further, in the magnetic amplifier 20, the ampere-turn of the saturable reactor 17 is set corresponding to the positive and negative output voltages of the secondary side of the transformer 13 so that self-feedback is performed.

In the above structure, the magnetic amplifier 20 is assumed.
Is removed and the secondary side of the transformer 3 is directly connected to the rectifying / smoothing circuit 24, the single-ended switching circuit 16
It is known that the voltage waveform induced on the secondary side of the transformer, that is, the secondary side of the transformer 13 and applied to the smoothing circuit 24 is as shown by the dotted line in FIG. 2b. That is, the transistor 1
2 becomes conductive at time t = 0, input DC power supply 1
A current is supplied from 1 to the parallel combined inductance of the exciting inductance L ₁ and the leakage inductance L ₂ (see FIG. 3) of the transformer 13. At this time, the current flowing through the combined inductance directly increases as shown by the dotted line in FIG. 2a. Then, after a predetermined time has passed, time t = ton
Then, when the transistor 12 suddenly becomes non-conductive, the current flowing through the above-mentioned combined inductance flows into the resonance capacitor 14 as it is because it has inertia. However, since the flowing-in direction is a negative direction with respect to the input DC 11, the terminal voltage of the resonance capacitor 14 gradually decreases from the value of the voltage + Ein of the input DC power supply 11 to become negative as the charging proceeds, and then becomes negative. After reaching the maximum value, it returns to + Ein again. This state is shown as a voltage waveform on the secondary side of the transformer 13, and is indicated by a dotted line in FIG. 2b. The characteristic of the change in the terminal voltage waveform of the resonance capacitor 14 is that the ratio of the area (voltage × time) between the positive potential and the negative potential is relatively small at 0.5 to 2.

With the above points in mind, the operation of FIG. 1 will be described. 2b shows the voltage applied to the magnetic amplifier, and FIG. 2c shows the magnetic amplifier 2 input to the smoothing circuit.
The output voltage (E ' _out ) of 0 is shown. First, when the transistor 12 becomes conductive, the rectifier diode 21 becomes conductive, considering the polarity of the transformer 13. Then, in the steady state, the parallel circuit of the smoothing capacitor 23 and the load 22 becomes equivalent to one battery. From these facts, the equivalent circuit of FIG. 1 becomes as shown in FIG. 3a. Incidentally, T is an ideal transformer, and 30 is the equivalent battery. in this case,
Since the saturable reactor 17 is not saturated in the initial stage of the conduction of the transistor 12, this impedance is very high. Therefore, almost all the current flowing from the input DC power supply 11 flows only in the exciting inductance L ₁ of the transformer 13. This is illustrated by the solid line t = 0 in FIG. 2a.
~ T _c . After that, when the saturable reactor 17 is saturated, its impedance becomes almost zero, so that the equivalent circuit of FIG. 1 becomes as shown in FIG. 3b. In the state of FIG. 3b, the current flowing from the input DC power supply 11 into the battery 30 via the leakage inductance L ₂ is rapidly added to the exciting inductance L ₁ , so that the slope of the current flowing out of the input DC power supply 11 becomes large. . This is illustrated by the solid line t = t _{c to} ton shown in FIG. 2a.
Is the period. During this period, the terminal voltage of the saturable reactor 17 becomes almost zero.

Next, when the transistor 12 becomes non-conductive, the input DC power supply 11 is disconnected and the saturable reactor 17 is saturated, so that the equivalent circuit of FIG. 1 becomes as shown in FIG. 3c. In this case, since the sum of the exciting current flowing through the transformer 13 and the current flowing through the load 22 at t = ton has inertia, the current flows into the resonance capacitor 14, and the terminal voltage of the capacitor 14 is changed. An attempt is made to change from positive to negative while drawing an arc of resonance as shown by the dotted line in FIG. 2b. However, in this state, the feedback diode 18 is given a forward bias and becomes conductive, and a current in the opposite direction to the above starts to flow through the saturable reactor 17 through the diode 18 and the variable resistance element 19. That is, the current accumulated in the leakage inductance and the current flowing in the variable resistance element 19 have opposite directions and flow in the saturable reactor 17 in a superposed manner. The period during which the current accumulated in the leakage inductance is flowing is t = ton shown in FIG. 2b.
.About.tm, the correspondence between the process in which the current becomes zero and the change in the magnetic flux of the saturable reactor 17 gradually returns from the saturated magnetic flux density Bs to the active state and shifts to the residual magnetic flux density Br as shown in FIG. From this saturation magnetic flux density Bs to the residual magnetic flux density B
Since the change in the magnetic flux density up to r is usually almost flat, the terminal impedance of the saturable reactor 17 is extremely low. As a result, as shown in FIG. 2bt = ton to tm, the potential is low even though the reset pulse is already applied between the terminals of the saturable reactor 17. After the current accumulated in the leakage inductance has completely flowed out, the magnetic flux density in the core of the saturable reactor 17 becomes lower than the residual magnetic flux density Br simply by the flyback pulse induced on the secondary side of the transformer 13. , Change in the active area. The lowest magnetic flux density Bomin is the value obtained by dividing the area B from time t = ton to td in the voltage waveform of FIG. 2b by the number of turns μ of the saturable reactor 17 and the cross-sectional area S of its core. Further, after time t = td, a positive potential is applied to the saturable reactor 17, so that the magnetic flux density of the saturable reactor 17 starts to increase again. Then, the time t = td shown in FIG. 2b.
When the voltage area A from to T + tc becomes equal to the above area B, the core of the saturable reactor 17 becomes saturated, and the impedance between the terminals becomes almost zero. Therefore, the equivalent circuit of FIG. 1 is as shown in FIG. 3b, and power is supplied to the load 22.

As is clear from the above description, the more rectangular the hysteresis characteristic of the core of the saturable reactor 17 is as shown in FIG. 4, the more the time t = tc, tm, td in FIG. 2b.
The time change of the waveform at becomes sharp, and good operation can be obtained. Therefore, it is an absolute condition that the hysteresis characteristic of FIG. 4 is maintained even at the operating frequency of the switching circuit. However, for a material with a large squareness ratio such as ordinary Senda, if a hysteresis curve is drawn with a direct current, a hysteresis curve as shown in FIG.
If a hysteresis curve is similarly drawn at a high frequency of about 100 KHz, the shoulder becomes stiff as shown in FIG. 5B and the coercive force becomes extremely large. This is the property of the material itself that cannot be improved even if the thickness of the core is reduced to about 10 μm. Using a core with such characteristics,
When controlling a high frequency switching waveform of about 0 KHz, it is difficult to obtain the voltage waveform as shown in FIG. 2b. That is, at the times t = te, tm, and td in the figure, the respective waveforms are tailed and become uncontrollable.

On the other hand, when a magnetic material such as an amorphous magnetic alloy is used, the squareness ratio B _r / B ₁₀ at direct current is 4 as shown in FIG. 6a.
0 to 50%, which is not as high as Sendelta, but 50KH
At a high frequency of about z, the squareness ratio becomes large at 94%,
It becomes possible to construct a magnetic amplifier. A coercive force H _c is a more important factor. Regarding this point, conventional magnetic materials such as Senda with a large squareness ratio at direct current have a small direct current coercive force H _c, but the eddy current loss increases at high frequencies, and the apparent coercive force H _c ′ becomes very large. . Sendadelta and the like cannot be used above 20 KHz due to the heat generated by this eddy current loss. On the other hand, the amorphous magnetic alloy does not lose its magnetic amplification function even if it contains a superposed eddy current loss. FIG. 7 shows a conventional representative magnetic material for a magnetic amplifier Sendelta i and (Co _0.90 Fe _0.06 C according to the present invention.
r _0.04 ) ₇₇ Si ₁₀ B ₁₃ Co-based amorphous magnetic alloy k
, The frequency dependence of the squareness ratio B _r / B ₁₀ is shown. Further, the dotted line in FIG. 7 indicates that the magnetic amplifier does not function at a frequency at which measurement is impossible. The above Co-based amorphous magnetic alloy k has a squareness ratio B _r / B ₁₀ of only 29% at direct current, but reaches 94% at ₁₀₀ KHz, and can be sufficiently used as a magnetic amplifier. Similarly, FIG. 8 shows SenDelta i as a conventional example and (Co _0.88 Fe _{0.06) according to the} present invention.
_{Cr 0.03 Ni 0.03) 75 Si 10} B 15 amorphous alloy l, Comparative Example
As a result, the frequency dependence of the coercive force H _c of the (Fe _0.45 Ni _0.55 ) ₇₈ Si ₁₀ B ₁₂ amorphous alloy m was shown. Here, the sen delta has a coercive force H _c of 0.9 Oe even at 20 KHz, and has a large value that cannot be measured at 20 KHz or more.

The following table shows various magnetic characteristics when the other amorphous magnetic alloy according to the present invention is used.

[0024]

[Table 1] All of the amorphous magnetic alloys described above are obtained by producing amorphous alloy ribbon by quenching the molten metal, and then subjecting it to heat treatment in a magnetic field-free state. For example, Co-based amorphous magnetic alloy (Co _0.88 F in the table)
For _{e 0.06 Ni 0.04 Nb 0.02) 75} Si 10 B 15, the amorphous alloy ribbon, was subjected to no magnetic field heat treatment 420 ° C. × 30 minutes, the heat treatment conditions of the quench (cooling) was added There is.
Next, the manufacturability of the amorphous magnetic alloy according to the present invention was evaluated.
Therefore, Co _0.92 Fe _0.06 Nb _0.02 ) ₇₅ Si _{10 according} to the present invention
B ₁₅ amorphous alloy, and Co ₇₀ Fe ₅ Si as a comparative example
About ₁₀ B ₁₅ amorphous alloy, Fe roll 300mmφ
After manufacturing a thin strip with a width of 5 mm and a plate thickness of 20 μm using
Wrap a thin strip of different size of tri-dal type
A magnetic core is prepared and further in a nitrogen atmosphere at 440 ° C. for 30 minutes
A high frequency magnetic property was measured after heat treatment and rapid cooling. this
At this time, as the size of the magnetic core, the average diameter is 7.5 mm (outer diameter 8
mm, inner diameter 7 mm), average diameter 10 mm (outer diameter 12 mm,
Inner diameter 8 mm), mean diameter 12.5 mm (outer diameter 15 mm, inner
Diameter 10 mm), average diameter 15 mm (outer diameter 18 mm, inner diameter 1
2mm), average diameter 17.5mm (outer diameter 21mm, inner diameter 1
4 mm) and average diameter 22 mm (outer diameter 26 mm, inner diameter 18
mm) for 6 kinds of samples to each amorphous magnetic alloy.
Produced by using an AC magnetic characteristic evaluation device.
The coercive force and squareness ratio at were calculated. The result is the obtained magnetic core
Fig. 11 shows the size dependence of H _c and B _r / B ₁₀ of
You The solid line in the figure represents (Co _0.92 F according to the present invention.
e _0.06 Nb _0.02 ) ₇₅ Si ₁₀ B ₁₅ Fabricated using an amorphous alloy
Are magnetic cores of H _c, a B _r / B _10, both manufactured of
It does not depend much on the size of the magnetic core, and
Amorphous magnetic alloy has good manufacturability, high squareness, and low coercive force.
Could be realized. On the other hand, in the comparative example
In a Co ₇₀ Fe ₅ Si ₁₀ B ₁₅ amorphous alloy,
Size affects its coercivity and squareness ratio at 100 KHz.
The coercive force is significantly increased especially in the high frequency range.
Therefore, it is understood that the productivity is significantly inferior.

From the above, the composition of the present invention is 20 to 1 as a magnetic material for a magnetic amplifier used in a high frequency switching circuit.
Coercive force H _c is 0.35 Oe or less at an operating frequency of 00 KHz,
Further, it can be seen that it is desirable that the squareness ratio B _r / B ₁₀ is 85% or more. That is, the amorphous magnetic alloy in the region surrounded by points A, B, C and D shown in FIG. 9 is preferable. In addition, FIG. 9 shows B _r / B ₁₀ and H _c with the frequency as a parameter.
The mark is direct current , the mark is 10 KHz, the mark is 20 KHz , the mark is 50 KHz, and the mark * is 100 KHz. In addition, the same parts as those in FIGS. 7 and 8 are designated by the same reference numerals.

The circuit to which the magnetic amplifier having the above magnetic characteristics is applied is not limited to that shown in FIG.
As shown in 0, the load circuit has a choke coil 5 for current smoothing.
Of course, it can be applied to a switching circuit provided with 0 and the free wheeling diode 51. In addition, FIG.
2, the same parts as those in FIG. 1 are designated by the same reference numerals.

Using the circuit shown in FIG. 1, the switching frequency was set to 50 KHz and the amorphous alloy was selected from the top 3
When the power supply efficiency was measured using the alloy of the second composition, it was high efficiency of about 85%. For comparison, an amorphous alloy (Co _0.82 Fe _0.06 Nb) outside the composition range of the present invention is used.
_0.12 ) ₇₅ Si ₁₀ B ₁₅ [coercive force of 20 KHz 1.3 Oe, B
When r / B10 = 0.99], the power supply efficiency was as low as about 67%.

[0028]

As described above in detail, according to the present invention, a magnetic amplifier which uses a saturable reactor and operates stably with high efficiency even at high frequencies can be constructed, and high frequency switching having excellent switching characteristics in the high frequency region. Circuit Co
A base amorphous magnetic alloy can be provided.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing an embodiment of a voltage resonance type high frequency switching circuit according to the present invention.

FIG. 2 is a waveform diagram for explaining the operation of FIG.

FIG. 3 is an equivalent circuit diagram in each operation period of FIG.

FIG. 4 is a diagram showing a hysteresis curve of a typical magnetic material for a magnetic amplifier.

FIG. 5 is a diagram showing an example of a hysteresis curve that changes between direct current and alternating current.

FIG. 6 is a diagram showing an example of a hysteresis curve that changes between direct current and alternating current.

FIG. 7 is a diagram showing the frequency dependence of the squareness ratio of each magnetic material.

FIG. 8 is a diagram showing frequency dependence of coercive force Hc of each magnetic material.

FIG. 9 is a diagram showing Br / B ₁₀ and Hc for each material with frequency as a parameter.

FIG. 10 is a circuit configuration diagram showing another embodiment.

FIG. 11: H of a magnetic core produced using each magnetic material
_c, shows the size dependence of B _r / B _10.

[Explanation of symbols]

11 ... Input DC power supply, 12 ... Transistor, 13 ... Transformer, 14 ... Resonance capacitor, 15 ... Damper diode, 17 ... Saturable reactor, 18, 21, 51 ... Diode, 19 ... Variable resistance, 22 ... Load, 23 … Smoothing capacitors.

Continued Front Page (56) References IEEE INTELEC (1979) HIRAMATSU, K .; HARA DA AND T. NINOMIYA "SWITCH MODE CONVERT ER USING HIGH-FREQ ENCY MAGNETIC AMPLI FIRE" P.N. 282-288 Journal of Japan Applied Magnetics Society, VOL. 5 N O. 2 (1981-3.) P. 165-168

Claims (1)

[Claims] 1. Equipped with magnetic amplifier using saturable reactor
For Co-based amorphous magnetic alloys for high-frequency switching circuits
Atomic% (Co _1-ac Fe _a M _c ) _1-d X _d 0.04 ≦ a ≦ 0.15 0.005 ≤ c ≤ 0.10 0.15 ≤ d ≤ 0.30 M is Nb, Cr, Mo, V, Ta, Ti, Zr, W
At least one element selected from X is B or B + Si However, if Si is contained, the amount of Si should be 25 atomic% or less.
Magnetic hysteresis curve shown and at 20-100 KHz
Line B _r / B _Ten Is 85% or more, coercive force H _c Is 0.35 Oe or less
High frequency switching circuit characterized by having the characteristics of
Co-based amorphous magnetic alloy for roads. [Claims]Two] Equipped with magnetic amplifier using saturable reactor
For Co-based amorphous magnetic alloys for high-frequency switching circuits
In atomic% (Co_1-abc Fe_a Ni_b M_c )_1-d X_d 0.04 ≦ a ≦ 0.150 <b ≦ 0.10 0.005 ≤ c ≤ 0.10 0.15 ≤ d ≤ 0.30 M is Nb, Cr, Mo, V, Ta, Ti, Zr, W
At least one element X selected from B or B + Si, if Si is contained, the Si content is 25 atomic% or less.
Magnetic hysteresis curve shown and at 20-100 KHz
Line B_r / B_TenIs 85% or more, coercive force H_c Is 0.35 Oe or less
High frequency switching circuit characterized by having the characteristics of
Co-based amorphous magnetic alloy for roads.