JPH0534420B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Industrial Application) The present invention relates to an amorphous alloy, and more specifically, to an amorphous alloy suitable as a magnetic core for a noise filter. (Prior art) (1) Amorphous alloys for soft magnetic materials Amorphous alloys have excellent soft magnetic properties due to their disordered structure, and in particular, the iron loss value is about 1/3 or less than that of conventional crystalline materials. High residual magnetic flux density, high saturation magnetic flux density,
It is well known that great efforts have been made to search for thermally stable compositions that have soft magnetic properties such as low coercive force and low core loss. Such soft magnetic properties are generally achieved when the BH curve is rectangular and vertically elongated (that is, the coercive force is small and the magnetization strength under a constant magnetic field is large). JP-A-54-148122 discloses 80 to 84 atomic percent iron,
It describes an amorphous alloy containing 12 to 15 atom % of boron and 1 to 8 atom % of silicon, having a high saturation magnetic flux density, and having good ductility and high temperature stability. U.S. Pat. No. 4,217,315 discloses Fe-B-Si
The composition of the system amorphous alloy is represented by a curve range, and as a typical example, the composition of Fe ₈₁ B _13.3-15.7 Si _3-5 has high saturation magnetization, high crystallization temperature, and low coercive force. Therefore, it is stated that it is excellent as an electric motor and a transformer. U.S. Pat. No. 4,219,355 describes Fe _a B _b Si _c C _d
In the amorphous alloy, those with a composition of a = 80.0 to 82.0 atomic%, b = 12.5 to 14.5 atomic%, Si = 2.5 to 5.0 atomic%, and C = 1.5 to 2.5 atomic% have high coercive force, magnetic flux density and It states that iron loss is excellent under commercial frequencies. JP-A-57-116750 discloses that in Fe _a Si _b B _c amorphous alloy, a=75 to 78.5 atomic %, b=4
It is described that excellent AC magnetic properties, that is, low power loss and low excitation force, can be obtained with a composition of ~10.5 at.% and C=11 to 21 at.%. This publication specifically states that the magnetic properties are improved by heat treatment in a magnetic field. JP-A No. 57-137451 is made of 77 to 80 atomic percent iron, 12 to 16 atomic percent boron, and 5 to 10 atomic percent silicon, and has a saturation magnetization of 15 kG or more and a coercive force of about
Less than 0.04Oe and 0.1W/lb (12.6kG, 60Hz)
It describes an amorphous alloy with a characteristic of iron loss of . JP-A No. 58-34162 discloses 78 to 82 atomic percent iron,
It describes an amorphous alloy consisting of 8 to 14 atomic % boron, 5 to 15 atomic % silicon, and 1.5 % or less carbon, and having good iron loss and magnetic flux density and magnetic aging resistance. JP-A-58-42751 discloses 77-79% iron, 8
~12% silicon, 9-11% boron, and 1-3%
It describes an amorphous alloy made of carbon whose magnetic properties change extremely little over time. JP-A-56-127749 discloses Fe _ax B _100-ax
In Si _zx , x = 4 to 9.5 atomic%, a = 82 to 86%
It is stated that an amorphous alloy with the following composition has thermally stable soft magnetic properties. According to Japanese Patent Application Laid-open No. 57-190304,
Fe _100-abc Mo _a X _b Y _c (However, X is Ni, Co, etc.
Y is Si, Al, B, C, etc., a=0.1~6, b=0
It has been stated that Mo is effective in improving the squareness ratio in an amorphous alloy having a composition of 60% or more in direct current magnetization (c = 15 to 30 at%). There is. Most of the above-mentioned known examples explore the suitable content range of Fe, B, Si, and C, with Fe being around 80 atomic %, and these compositions can exhibit excellent characteristics as a magnetic core for a noise filter. Not found in the official bulletin. However, JP-A-57-
No. 116750 explored suitable B and Si contents at 75 atomic percent Fe, but found that square and vertically elongated
Since the amorphous alloy is heat-treated in a magnetic field to form a BH curve, characteristics suitable for a magnetic core for a noise filter cannot be obtained. Moreover, the one disclosed in JP-A-57-190304 in which the squareness ratio is improved by Mo is not suitable for a magnetic core for a noise filter. Proc.4th Int.Conf, on Rapidly Quenched
According to Metals (Sendai, 1981) pp1035-1038, (Fe _0.76 B _0.14 Si _0.10 ) ₉₈ (Be, C, Al, Co,
Ni, Cr, Nb) ₂ and (Fe _1-x Co _x ) ₇₄ Cr ₂ B ₁₄ Si ₁₀
Research on the frequency characteristics of magnetic permeability has been published. According to this study, certain frequencies (e.g.
An abnormal phenomenon was discovered in which the magnetic permeability significantly decreased by approximately 1/5 at frequencies (near 50kHz). The reason for this abnormal decrease in magnetic permeability is based on magneto mechanical resonance, a phenomenon that is mainly influenced by magnetostriction. It is stated in the above published paper that a magnetic anomaly phenomenon occurs significantly. (2) Amorphous alloy for noise filter magnetic core An example of a noise filter will be explained below with reference to FIG. 2. As shown in FIG. 2, the noise filter 1 includes a magnetic core 1A and a pair of windings 2A, 2B. When an AC commercial voltage is applied to the noise filter and passes through the windings 2A, 2B, the magnetic flux is occurs, but each winding 2A and 2B
The winding direction of the winding is determined so that the total magnetic flux generated by the winding is zero. Winding 2A and 2
Capacitors 3, 4A and 4B are connected between the capacitors B, and the connection point between the capacitors 4A and 4B is grounded. As shown in FIG. 3, when the noise input voltage exceeds a certain critical point, the noise output voltage increases rapidly. The reason for this is noise filter 1
This is because the magnetic core shown in FIG. 2 becomes magnetically saturated, and when such saturation occurs, the noise filter 1 ceases to function. The noise output voltage (that is, the slope of the curve) in the region where the noise output voltage of the noise filter 1 is low is inversely proportional to the magnetic permeability of the magnetic core 1A, that is, the inductance of the magnetic core. The use of an amorphous alloy as a magnetic core for a noise filter is known from JP-A-56-46516. However, the Fe ₈₀ B ₁₈ Si ₂ alloy described in this publication cannot remove a high voltage pulse of 1000 V or more and a duration of 0.1 μsec or less when this pulse is generated. JP-A-57-24519 discloses, for example, Fe ₈₁ B _7.1
It is described that noise removal characteristics are improved by partially forming microcrystals in an amorphous alloy having a composition of Si _1.9 . JP-A-57-24158 specifies the BH curve of an amorphous alloy for a noise filter magnetic core.
In other words, as explained in Figures 1 and 2, having a noise filter magnetic core with high inductance, that is, high magnetic permeability, generally lowers the output noise voltage, but increasing the magnetic permeability Square and vertically long BH
Once the curve is obtained, on the other hand, since large voltage pulses cannot be removed, 2000G≦B ₂ ≦0.7Bs(G) (however,
_B2 is the magnetic flux density at 50kHz and magnetization strength 2Oe, and Bs is the saturation magnetic flux density) and BH
Japanese Patent Application Laid-Open No. 1987 (1982) identified a curve as an inclined shape.
-Described in Publication No. 24158. This publication lists Fe ₇₆ Co ₄ B _18.9 Si _2.1 as amorphous alloys,
Examples include Fe _78.4 Ni _1.6 B ₁₂ Si ₈ and Fe _62.4 Ni ₁₆ Mo _1.6 B ₁₆ Si ₄ . JP-A-56-185201 states that μi=2000 to 5000,
Br≦3000, B ₂ =6~9kG, Bs≧12kG (However, μi
is the initial permeability)
It has been stated that amorphous alloys with curves can remove large voltage pulses as noise filters. When comparing magnetic cores for noise filters with iron cores for general transformers, electric motors, etc., there are the following differences in preferable magnetic properties. In other words, as a magnetic core for a noise filter, the BH curve is inclined (that is, it has a constant magnetic permeability characteristic in which the magnetic permeability μ does not change due to the magnetic field, and the residual magnetic flux density Br
However, such a BH curve is inconvenient for iron cores of transformers, electric motors, etc. If an abnormal magnetic permeability phenomenon occurs in an amorphous alloy, it is undesirable as a magnetic core for a noise filter.
According to the report of Proc. Rapid Quench Metal mentioned above, it is thought that if the composition of the amorphous alloy is adjusted to zero magnetostriction, the desired characteristics as a noise filter magnetic core can be provided. but
With a zero magnetostriction composition of the Co-based amorphous alloy, properties other than magnetostriction, particularly low magnetic flux density and large changes in magnetic properties over time, make it impossible to obtain desired properties in the noise filter magnetic core. (Problems to be Solved by the Invention) The present inventors investigated in detail the high voltage pulse rejection characteristics of a magnetic core made of an amorphous alloy for a known noise filter magnetic core, and found that the characteristics deteriorated during use of the magnetic core. I found out what happens. More specifically, we have discovered a phenomenon in which the desired high voltage pulse characteristics are obtained during the first use of the magnetic core, but the desired high voltage pulse characteristics are no longer obtained during subsequent uses. Here, this phenomenon will be referred to as deterioration of pulse resistance characteristics. Further, the present inventors investigated the relationship between the composition of the amorphous alloy and its pulse resistance characteristics, and as a result, they found that the pulse resistance characteristics vary greatly depending on the composition. Based on this knowledge, the present inventors
or an A component consisting of a combination of Fe and one or more other transition metal elements, a B component consisting of at least one of B, C and P, and at least one of Si and Al.
The amount of the A component, the B component and the C component is on the line of the curve X shown in FIG. Other transition metals include Mn, Mo,
Patent Application No. 58-206898 (Japanese Unexamined Patent Publication No. 58-206898) discloses an amorphous alloy in which at least one element selected from the group consisting of Nb and Cr replaces Fe in a content of 5 at % or less.
60-100650). An object of the present invention is to select a specific composition for an amorphous alloy used in a magnetic core for a noise filter, so that the alloy can withstand high voltage pulses repeatedly applied to the magnetic core. The object of the present invention is to provide an amorphous alloy that can prevent deterioration of pulse characteristics and eliminate stable high voltage pulses for use in magnetic cores for noise filters. The object of this invention is to provide an amorphous alloy having pulse resistance characteristics and magnetic permeability characteristics that are equivalent to or better than those of No. 1, and to expand the range of A, B, and C components. (Means for Solving the Problem) The present inventor further researched the deterioration of the pulse resistance characteristics of amorphous alloys, and found that the amorphous alloy of the previous application in which Fe was replaced with Mo had an improvement equal to or higher than that of the previous application. It has been found that good pulse resistance properties are found outside curve X (FIG. 1). The present invention will be explained below. In the following explanation, the pulse characteristic deterioration rate is a percentage expressed by: Deterioration rate=μe (after application of a magnetic field of 4 Oe)−μe (demagnetization)/μe (demagnetization)×10 (%). However, μe (demagnetization)
is the magnetic permeability at 100kHzmOe (0.002Oe).
Moreover, demagnetization is a magnetized state with zero magnetic flux density.
Prior to defining the above deterioration rate, the present inventors manufactured a toroidal amorphous alloy magnetic core with an outer diameter of 31 mm, an inner diameter of 19 mm, and a height of 8 mm, and then applied a magnetic field of 20 Oe or less to the magnetic core and demagnetized it. , μe, that is, μe, was measured at 100kHz2mOe in each state after demagnetization and application of a magnetic field, and the rate of change of μe (after magnetic field application) − μe (demagnetization)/μe (demagnetization) was measured. The measurement results are shown in FIG. As a result, it was found that the decrease in magnetic permeability μe was greatest when the applied magnetic field was 4 Oe. That is, the fourth
As can be seen from the figure, the magnetic permeability (μe) of the amorphous alloy after a 4Oe magnetic field is applied is the original magnetic permeability (μe).
It is about 30% lower than that of the previous year. This result shows that high voltage pulses, which should originally be removed, are also caused by external noise.
This means that after applying a voltage pulse corresponding to a magnetic field of Oe, the rejection rate of that input pulse deteriorates by about 30%. As described above, since the pulse resistance characteristics deteriorate most when the applied magnetic field is 4 Oe, the pulse characteristics deterioration rate was determined as described above. By determining the pulse characteristic deterioration rate in this way, it becomes possible to control the maximum pulse characteristic deterioration that can occur in an actual magnetic core. i.e. 4
By measuring μe in a magnetic field of Oe and determining the above-mentioned pulse characteristic deterioration rate, it is possible to effectively prevent deterioration of pulse resistance characteristics that may occur due to a high noise pulse voltage equivalent to or more than a magnetic field of 4 Oe. becomes possible. Magnetic permeability (μe) also represents the noise pulse rejection property of a magnetic core under conditions where a magnetic field of 2 mOe or more is applied to the magnetic core by a noise pulse voltage. The effects of Mo discovered by the present inventor are explained in Table 1.

[Table] Table 1 shows the results of measuring various properties of an amorphous alloy with a composition of Fe _76-x Mo _x Si ₆ B ₁₈ . It can be seen from Table 1 that the deterioration rate is significantly reduced by adding Mo. In addition, μ ₂ after pulse deterioration is
100kHz, 2mOe after applying 4Oe magnetic field pulse
(0.002 Oe) (the same applies below). The present invention is based on the knowledge that Mo has a unique effect on pulse resistance deterioration as described above. The reasons for the limitations of the present invention will be explained below. The content range of the A, B, and C components in the amorphous alloy of the present invention is set on or within the curve Y in FIG. 1 because if it is outside this range, the pulse resistance will deteriorate and μ ₂ = 4000 may not be secured. In other words, even outside this range, Fe
Although the desired magnetic flux density and soft magnetic properties such as low iron loss can be obtained as a normal soft magnetic material with a concentration of around 80%, the pulse resistance properties are significantly deteriorated.
Furthermore, in the amorphous alloy of the present invention, the range on or inside the curve Y and overlapping with the X curve (Y'-X range) was excluded because in this range μ ₂
This is because it is generally low at about 3000. In the present invention, magnetic permeability (μ ₂ ), residual magnetic flux density (Br), and magnetic flux density (B ₂ ) are determined so as to effectively remove high voltage pulses as a magnetic core for a noise filter. To explain it individually, first, when the magnetic permeability (μ ₂ ) is less than about 4000, the inductance of the noise filter magnetic core is too low, so the noise attenuation rate becomes low and the output pulse voltage becomes high, which is undesirable. Next, it is preferable that the residual magnetic flux density (Br) is as small as possible; when Br>3kG, the constant magnetic permeability of the magnetic permeability μ is lost, and the composition region with good pulse voltage removal rate tends to become narrow, which is not desirable. . Furthermore, if the magnetic flux density (B ₂ ) is less than 5 kG, the noise allowable input voltage will be low, which is not preferable. On the other hand, when the magnetic flux density (B ₂ ) exceeds 11 kG, the noise tolerance voltage becomes low because a BH curve part with no constant magnetic permeability occurs, and the sudden rise in the noise output voltage shown in Figure 3 is caused by a low noise input voltage. It's starting to happen and I don't like it. In the present invention, Mo is used as an additive element because of the Mn, Mo, and
As a result of comparing Nd, Cr, and other metal elements, it was confirmed that Mo is the most effective additive element for amorphous alloys for noise filters. The results of this comparison are shown in Table 2.

[Table] Table 2 shows the characteristics of the basic composition Fe ₇₆ Si ₆ B ₁₈ in which Fe is replaced with the component amounts shown in the table. From top to bottom, μ ₂ after demagnetization, μ ₂ after pulse deterioration, and deterioration. They are shown in order of percentage. The properties of Fe ₇₆ Si ₆ B ₁₈ were as follows. μ ₂ (after demagnetization) = 5000 μ ₂ (after pulse deterioration) = 4000 Deterioration rate = 20% As can be seen from Table 2, Mo reduces the deterioration rate by 20%.
However, W and Mn hardly change these properties, Ni degrades all properties, and other elements significantly increase μ ₂ (after demagnetization and pulse degradation ₎ while maintaining (After demagnetization and pulse deterioration)
or the deterioration rate. In addition, 1
Addition of % Ti makes it impossible to produce an amorphous alloy ribbon, and addition of 3% W also makes it impossible to produce a non-crystalline alloy ribbon. As mentioned above, Mo is the most effective, but this does not preclude the addition of some amount of a metal element other than Mo. The degree of deterioration of pulse characteristics referred to in the present invention is not specified in industrial standards for inductors and the like. West Germany is the industrial standard for general inductors.
VDEO565Teil3.3.6 Inductance, 3.6.2 shows the allowable deviation from the inductance rated value when supplying current to the rod core and dust core chain yoke.
20% are cited. It was found that the amorphous alloy according to the present invention satisfies the above-mentioned inductance tolerance of ±20% without any problem because the contents of the A, B, and C components are determined as described above. The composition and structure of the amorphous alloy of the present invention will be explained in more detail below. The A component is Fe and Mo or Fe plus Mo.
and other transition metal elements (Sc~Zn, Y~Cd, La~
Hg, Ac ~) - hereinafter referred to as M component - is used, but specific examples of M components other than Mo include Co,
Ni, Cr, Cu, Nb, Mn, Ti, W, V, Zr, Ta,
One or more types of Y or rare earth elements can be mentioned. Of the M components, Ni and Co are approximately 20 atomic % or less relative to Fe, and other M components are generally approximately 5
It can contain atomic percent. As the M component,
Preference is given to Mn, Cr, Nb, Ni and Co, especially Mn. As the B component, Si alone or a combination of Si and Al is used, and as the C component, B alone or a combination of B and at least one of C and P is used. However, Al is the sum of Si and Al components.
Preferably, the content is 10% or less, or C is 20% or less of the total of B, C, and P components, and P is 5% or less. The above A, B, and C components are the A, B, C three-component system coordinates.
If it is on the y ₁ curve (FIG. 1) or within the range, μ ₂ (after demagnetization) ≧5000 is obtained, and if it is on the y ₂ curve or within the range, μ ₂ (after demagnetization) ≧6000 is obtained. The structure of the amorphous alloy of the present invention is substantially amorphous, and a small amount of precipitated microcrystals may be present.
A small amount of precipitated crystallites is formed by heating the fully amorphous alloy below the crystallization temperature, with temperature and time dependent heat treatment conditions. For amorphous alloys containing such precipitated microcrystals, the amorphous alloy ribbon is reduced to a thickness of 50 nm or less by electrolytic polishing or ion etching, and then examined using a transmission electron microscope at an accelerating voltage of 100 to 200 kV and a magnification of 10,000 kV. When observed at ~100,000x magnification, the presence and amount of microcrystals can be confirmed by contrast. The presence of microcrystals and the crystal structure can also be analyzed by selected area electron diffraction. Note that when microcrystals precipitate in an amorphous alloy, the saturation magnetic flux density (Bs) hardly changes and the residual magnetic flux density (Br) decreases. Therefore, desirable characteristics as a noise filter can be obtained by subjecting the amorphous alloy composition of the present invention to a microcrystal precipitation heat treatment as required. Therefore, in the amorphous alloy of the present invention, if the above-mentioned Br≦3kG and B ₂ =5 to 11kG cannot be obtained in a completely amorphous state, a heat treatment is performed to precipitate or not precipitate microcrystals, and the prescribed state is achieved. It is necessary to try to obtain Br and _B2 . The proportion of microcrystals is less than 3% by area,
Generally it is 0.5 area% or less. Next, Table 3 shows an example of heat treatment conditions for precipitating microcrystals.

[Table] Table 3 shows the data obtained by measuring the magnetic properties of the Fe ₇₅ Mo ₅ Si ₁₂ B ₈ alloy after the heat treatment shown in the table ₍ hours/minutes). μ ₂
(Pa) indicates the magnetic permeability after pulse deterioration. In Table 3, 3-7 are heat treatment conditions for achieving the magnetic properties of the present invention. Further, although magnetic permeability is an important element in the present invention, since the magnetic permeability of an amorphous alloy is structurally sensitive, it is not necessarily easy to accurately measure it. Although the inventor's experiment used HP 4274A measuring device to measure as accurately as possible, it should be understood that the magnetic permeability measurement may have an error of up to 5%. As mentioned above, it is preferable that Br be as small as possible, and even if Br≒0 in fact, as long as B ₂ and μ ₂ are within a predetermined range, high voltage pulses can be applied to the magnetic core made of the amorphous alloy of the present invention. It should be noted that the deterioration of the magnetic core due to magnetic noise is small, that is, the change in inductance is small, and high voltage pulses can be stably removed. Next, the heat treatment conditions of the Fe ₇₃ Mo ₅ Si ₉ B ₁₃ alloy were changed to vary the μ ₂ after demagnetization over a wide range.
We investigated how μ ₂ after pulse deterioration and the deterioration rate are affected by μ ₂ after demagnetization. The results are shown in FIG. As shown in Figure ₅ , μ ₂ (after pulse deterioration) is slightly lower than the line μ 2 (after demagnetization) = μ ₂ (after pulse deterioration) when μ ₂ (after demagnetization) ≦ about 5500 or less. The deterioration rate increases significantly when μ ₂ (after demagnetization) is greater than approximately 5500. The present inventors confirmed the tendency as shown in Figure 5 for compositions within the range of the present invention, and found that Mo is effective in suppressing this tendency, and has a good property even at high magnetic permeability of μ ₂ ≧6000. It was confirmed that pulse resistance was obtained. (Function) Table 4 shows changes in magnetic properties depending on the amount of Mo added.

[Table] From the viewpoint that the addition of Mo, which is an important feature of the present invention, may reduce magnetostriction and reduce magneto-mechanical resonance, the deterioration rate may be reduced. When the magnetostriction of the amorphous alloys was measured, the magnetostriction constants of the alloys excluding Co, Ti, and W were almost the same. In other words, even in the case of amorphous amorphous alloys having almost the same magnetostriction constant, there are differences in pulse resistance characteristics, and it was found that the composition is affected. Further, since the squareness ratio of the amorphous alloy of the present invention is less than 50%, usually 20% or less, it is not thought that Mo has a significant effect on the squareness ratio. As mentioned above, the inventors have devised ideas from several viewpoints, but the inventor has not been able to elucidate why Mo brings about the effect of improving pulse resistance. The amorphous alloy according to the present invention is prepared as a ribbon having a thickness of 10 to 50 μm by a conventional single-roll method, and then formed into a wound magnetic core by winding the ribbon. The manufacturing method of the wound magnetic core is disclosed in the patent application filed by the present inventor.
The manufacturing method may be the same as that described in connection with FIGS. 2 and 3 of Japanese Patent No. 57-24518. Further, an example of a noise filter circuit incorporating a magnetic core may be the same as that shown in FIGS. 6 and 7 of Japanese Patent Application Laid-Open No. 57-24518. Examples of the present invention will be compared below. (Example) A film with a thickness of 18 μm and a width of 8
After manufacturing an amorphous alloy ribbon of mm, it is made into a wound core,
Heat treatment was performed and the properties as a magnetic core were evaluated. Table 5 shows the composition and properties of the amorphous alloy.

【table】

[Table] From Table 5, good pulse resistance characteristics are achieved by amorphous alloy A component (combination of Fe and Mo, etc.), B component (Si),
It can be seen that the C component (B) can be obtained by using Mo with a content of 3% or more. (Effect of the invention) According to the amorphous alloy of the present invention, which has significantly improved pulse resistance as a magnetic core for a noise filter compared to conventional amorphous alloys, remarkable stabilization of the homogeneity of the noise filter is achieved. be done. In other words, the positive or negative noise pulse voltage that should be removed by the noise filter varies greatly depending on the inherent nature of the noise, and it is impossible to predict whether positive or negative pulse voltage will occur. Since there has been no evaluation method, it has not been recognized that amorphous alloy compositions, which have been the subject of much research, have poor pulse resistance. When the composition range of the amorphous alloy was examined using the pulse characteristic deterioration rate defined by the present invention, it was found that a specific composition has the effect of stably removing noise pulse voltage of any size. I understand. Furthermore, according to the present invention, by adjusting the amount of each component, a high magnetic permeability of μ ₂ (after demagnetization) of 6000 or more can be obtained, thereby increasing the pulse rejection rate and achieving a high μ
The present invention has great significance in preventing malfunctions of electronic equipment caused by noise, since B ₂ can also be increased in the state, and thus the allowable noise input voltage can also be increased.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the composition of the amorphous alloy according to the present invention, Fig. 2 is a drawing showing an example of a noise filter circuit, Fig. 3 is a graph conceptually showing the characteristics of the noise filter, and Fig. 4 is a diagram showing the composition of the amorphous alloy according to the present invention. Graph showing the relationship between applied magnetic field, magnetic permeability, and its rate of change, No. 5
The figure is a graph showing the relationship between μ ₂ after demagnetization, μ ₂ after pulse deterioration, and the deterioration rate.

Claims (1)

[Claims] 1 A component consisting of a combination of Fe and Mo, a B component consisting of Si alone or a combination of Si and Al, and C consisting of B alone or a combination of B and at least one of C and P. consisting essentially of the above-mentioned A
The content of Mo in the components is 7% or less of the entire alloy, and the amounts of the A component, B component, and C component are outside the area surrounded by the curve X shown in FIG. In a BH loop that is on the Y line or in the area surrounded by the curve Y, and has a magnetic permeability (μ ₂ ) of approximately 4000 or more when measured in a magnetic field of 100 kHz and 2 mOe, and a frequency of 2 kHz and a maximum applied magnetic field of 2 Oe. An amorphous alloy characterized by having a residual magnetic flux density (Br) of 3 kG or less, a magnetic flux density (B ₂ ) at 2 Oe of 5 kG or more and 11 kG or less, and little deterioration in pulse resistance characteristics. 2. The amorphous alloy according to claim 1, wherein the Mo content is 3% or more.