JPH0533302B2 - - Google Patents

Description

[Detailed description of the invention]

TECHNICAL FIELD 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 can be reduced to about 1/3 or less than that of conventional crystalline materials. Due to its 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 iron 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 expressed by a curve range, and as a typical example, the composition Fe ₈₁ B _13.3-15.7 Si _3-5 has a high saturation magnetization, a high crystallization temperature, and a 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 system 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 the following characteristics: 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, ie, low power loss and low excitation force, can be obtained with a composition of ~10.5 at.% and c=11-21 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, 60
It describes an amorphous alloy with a characteristic of iron loss (Hz). 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 No. 58-42751 discloses that 77-79% iron, 2
~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. 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 No. 57-
No. 116750 explores suitable B and Si contents at 75 atomic percent Fe, but since the amorphous alloy is heat-treated in a magnetic field to form a rectangular and vertically elongated BH curve, there is noise. Characteristics suitable for magnetic cores for filters have not been obtained. (2) Amorphous alloy for noise filter magnetic core An example of a noise filter will be explained below with reference to FIG. 1. As shown in FIG. 1, 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. 2, 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 (FIG. 1) 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 occurs. 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 ≦0.7B _s (G) (however,
B ₂ is the magnetic flux density at 50KHz and magnetization strength 2Oe, and B _s 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 . Patent Application No. 185201/1985 states that μi=2000 to 5000,
Br≦3000, B ₂ = 6~9KG, B _s ≧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 and 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 B _r
However, such a BH curve is inconvenient for iron cores of transformers, electric motors, etc. Therefore, the state of the art from which the present invention is based is that the BH curve of an amorphous alloy for a noise filter magnetic core has a sloped shape compared to the rectangular and vertically long BH curve of an amorphous alloy for a normal soft magnetic material. For example, an amorphous alloy consisting of about 80% of the total amount of Fe, Co or Ni, and the balance B and/or Si, which is controlled to have the shape defined in Japanese Patent Application No. 185201/1982, is known. It is a familiar thing. The present inventors investigated in detail the high voltage pulse removal 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. Specifically, we have discovered a phenomenon in which the desired high-voltage pulse characteristics are obtained when the core is used for the first time, 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, as a result of investigating the relationship between the composition of an amorphous alloy and its pulse resistance characteristics, the present inventors discovered that the pulse resistance characteristics vary greatly depending on the composition, and completed the present invention. OBJECTS OF THE INVENTION An object of the present invention is to select a specific composition of an amorphous alloy used in a magnetic core for a noise filter so that the alloy can be used in the magnetic core and repeatedly subjected to high voltage pulses. It is an object of the present invention to provide an amorphous alloy that can prevent deterioration of pulse resistance characteristics during operation and stably remove high voltage pulses, for use in a magnetic core for a noise filter. Structure of the Invention The object of the present invention is to provide an A component consisting of Fe alone or a combination of Fe and one or more other transition metal elements;
It consists essentially of a B component consisting of a single component or a combination of Si and Al, and a C component consisting of a single B component or a combination of B, C, and P, and the amounts of the A component, B component, and C component are as shown in FIG. on the line of curve X shown in or within the area surrounded by this curve X, and
Magnetic permeability (μ2) measured in a magnetic field of 100KHz and 2mOe
is approximately 2,000 or more and approximately 5,000 or less, the residual magnetic flux density (Br) in the B-H loop measured at a frequency of 2KHz and a maximum applied magnetic field of 2Oe is 3KG or less, and the magnetic flux density (B ₂ ) at 2Oe is 6KG or more and 9KG or less. ,
This is achieved by providing an amorphous alloy characterized by little deterioration in pulse resistance properties. The properties of the amorphous alloy of the present invention will be explained in detail below. The reason why 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 X in Fig. 3 is because if it is outside this range, the pulse resistance characteristics will deteriorate rapidly. It is. In other words, even outside this range, the desired soft magnetic properties such as high magnetic permeability, magnetic flux density, and low core loss can be obtained as a normal soft magnetic material centered on Fe = 80%, but the pulse resistance properties are poor. Significant deterioration. On the other hand, if the A, B, and C components are on or within the curve X, the soft magnetic properties are somewhat inferior to those outside the curve Characteristic deterioration is extremely reduced. In the present invention, magnetic permeability (μ2), 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 (μ2) is less than about 2000, the inductance of the noise filter magnetic core is too low, which is undesirable because the output pulse voltage becomes high. on the other hand,
When the magnetic permeability (μ2) exceeds about 5000, there is a tendency that high pulse voltages cannot be removed due to a significant saturation tendency at low voltage pulses. Next, it is preferable that the residual magnetic flux density (Br) is as small as possible, Br>3KG
In this case, the constant magnetic permeability of the magnetic permeability μ tends to be lost, and the composition region where the pulse voltage removal rate is good tends to become narrow, which is undesirable. The degree of deterioration of pulse characteristics referred to in the present invention is not specified in industrial standards for inductors and the like. The industrial standard for general inductors is the West German VDEO
565 Teil 3.3.6 Inductance, 3.6.2. has a tolerance of ±20% from the inductance rated value when supplying current to the rod core and dust core chain yoke.
are listed. 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. Embodiments of the present invention will be described below. In the following explanation, the pulse characteristic deterioration rate is μe (after applying a magnetic field of 4 Oe) − μe (demagnetization) / μe (demagnetization) ×
It is a percentage expressed as 100 (%). However, μe is 100K
Magnetic permeability at Hz2mOe (0.002Oe). Moreover, demagnetization is a magnetized state with zero magnetic flux density. Prior to defining the above deterioration rate, the inventors
A toroidal amorphous alloy magnetic core with a diameter of 31 mm, an inner diameter of 19 mm, and a height of 8 mm was manufactured, and a magnetic field of 20 Oe or less was applied to the magnetic core and then demagnetized. μe was measured, 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, we found that the decrease in magnetic permeability μe was greatest when the applied magnetic field was 4 Oe. That is, as can be seen from FIG. 4, the magnetic permeability (μe) of the amorphous alloy after a 4Oe magnetic field is applied is approximately 30% lower than the original magnetic permeability (μe). This result shows that the high voltage pulse, which should originally be removed, is 4Oe due to external noise.
This means that after applying a voltage pulse equivalent to a magnetic field of , 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. 4Oe
By measuring μe in a magnetic field of 4 Oe and determining the deterioration rate of the pulse characteristics described above, it is possible to effectively prevent deterioration of the pulse resistance characteristics that may occur due to a high noise pulse voltage equivalent to a magnetic field of 4 Oe or more. It becomes possible. Magnetic permeability (μe) also represents the noise pulse rejection characteristic 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. According to the present invention, the pulse characteristic deterioration rate is suppressed to 10% or less. Furthermore, by further specifying the contents of the A, B, and C components, the pulse characteristic deterioration rate can be suppressed to 5% or less. FIG. 5 is a ternary phase diagram of A, B and C,
X is a curve showing the component range of the present invention, and Y
and Z are curves showing compositions with pulse characteristic deterioration rates of -20% and -30%, respectively. In addition, the A component is approximately
If it is less than 70%, it becomes difficult to make the alloy consisting of A, B, and C components amorphous. Figure 5 also shows, for reference, the magnetic permeability measured at 100KHz after demagnetization by U, V and W, respectively, is 10000, 7500 and 7500.
The A, B and C component contents of 5000 are shown. Within the range of curve U, the magnetic permeability is maximum below 25KHz. This curve U almost coincides with the range where the magnetic permeability μ2 is maximum. Therefore, the content range of the A, B, and C components in which the pulse characteristic deterioration rate is low does not match the range in which the magnetic permeability is maximum. Furthermore, in FIG. 5, by dotted line S,
A, B, and C with a saturation magnetic flux density (Bs) of approximately 15 KG when measured with a magnetization strength of 10 Oe at 2 KHz alternating current.
Ingredient content is indicated. Right side of curve S (high
Bs becomes high on the Fe side). Therefore, the X curve according to the present invention is A, where the saturation magnetic flux density (Bs) is low,
It can be seen that the B and C component contents are the same. Hereinafter, the composition and structure of the amorphous alloy of the present invention will be explained in more detail. As the A component, Fe alone or Fe and other transition metal elements (Sc~Zn, Y~Cd, La~Hg, Ac~)
-hereinafter referred to as M component- is used, and preferred specific examples of M component include Co, Ni, Cr, Cu,
One or more of Mo, Nb, Mn, Ti, W, V, Zr, Ta, Y, and 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 atomic %.
It can contain. M component is Mn,
Cr, Mo, Nb, Ni and Co, especially Mn are preferred. 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, C, and P is used. However, Al is
Preferably, it is 10% or less with respect to the total of Si and Al components, C is preferably 20% or less with respect to the total of B, C, and P components, and P is 5% or less. The above A, B and C components are
In A, B, C ternary system coordinates (atomic%) (73,
9, 18), (73, 12, 15), (76, 9, 15), and (76, 6, 18), the deterioration of the pair of pulses will be significantly reduced. Furthermore, as optional components, the total amount of B component and C component is within the range of 10 atomic % or less, and 1 of Be, Ge, Sb, In, etc.
Even if more than one species is contained, the effects of the invention will not be diminished. 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. When an amorphous alloy containing such precipitated microcrystals is subjected to X-ray diffraction, the diffraction spectrum shows a pattern in which peaks indicating the presence of crystalline material are superimposed on a halo characteristic of amorphous material. . In addition, in the diffraction image, a spot is superimposed on the halo, and a Debye-Schiler ring with a predetermined ring diameter and ring width appears. 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 = 6 to 9KG 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 . In addition, as mentioned above, Br
is preferably as small as possible, and even if Br≒0 in fact, as long as B ₂ and μi are within a predetermined range, deterioration of the magnetic core due to high voltage pulse noise is small in the magnetic core made of the amorphous alloy of the present invention. , that is, the change in inductance is small, and high voltage pulses can be stably removed. By taking the area ratio between the halo and the peak of the diffraction spectrum of the amorphous alloy containing the above-mentioned precipitated microcrystals, the abundance ratio of crystals and specific crystalline materials can be determined. The crystalline/amorphous ratio is usually preferably about 50% or less. 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%. 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. The composition and properties of the amorphous alloy are shown in Table 1.

[Table] In the table, samples marked with * indicate the composition of the present invention, and samples without * are comparative examples. From Table 1, it can be seen that good pulse resistance characteristics are due to the amorphous alloy A component (Fe alone or
combination of Fe and Mn, etc.), B component (Si alone or Si
and Al), and C component (B alone or B,
It can be seen that the combination of C and P can be obtained critically depending on the content. Effects 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. . 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. Therefore, the present invention has great significance in preventing malfunctions of electronic equipment caused by noise pulses.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of a noise filter circuit, Fig. 2 is a graph conceptually showing the characteristics of the noise filter, Fig. 3 is a diagram showing the composition of the amorphous alloy according to the present invention, 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 diagram showing the contents of A, B, and C components at which the same characteristics can be obtained. X is a composition line where good pulse resistance characteristics are obtained according to the present invention, U, V and W are composition lines where a certain magnetic permeability is obtained and correspond to 10,000, 7,500 and 5,000, respectively, and Y and Z are respectively. S is the composition line where the pulse characteristic deterioration rate is -20% and -30%, and S is the composition line where the saturation magnetic flux density is about 15KG.

Claims (1)

[Claims] 1 Component A consisting of Fe alone or a combination of Fe and one or more other transition metal elements, Si alone or Si and Al
It consists essentially of a B component consisting of a combination of , and a C component consisting of B alone or a combination of B, C and P, and the amounts of the A component, B component and C component are shown in FIG. It is located on the line of curve In the B-H loop, the residual magnetic flux density (Br) is 3KG or less, and the magnetic flux density (B ₂ ) at 2Oe
An amorphous alloy that is characterized by having a weight of 6KG or more and 9KG or less, with little deterioration in pulse resistance characteristics. 2 The other transition metal element is Co, Ni, Cr,
Cu, Mo, Nb, Mn, Ti, W, V, Zr, Ta, Y
The amorphous alloy according to claim 1, characterized in that the amorphous alloy is at least one selected from the group consisting of rare earth elements and rare earth elements. 3 The other transition metal elements are Mn, Cr, Mo,
The amorphous alloy according to claim 2, characterized in that the amorphous alloy is at least one selected from the group consisting of Nb, Ni, and Co. 4. Claim No. 4, characterized in that the other transition metal element is at least one selected from the group consisting of Ni and Co, and the content thereof is such that it replaces 20 atomic percent or less of Fe. Amorphous alloy according to item 3. 5 The other transition metal elements are Mn, Mo, Nb and
Claim 3, characterized in that it is at least one selected from the group consisting of Cr, and its content is 5 at % or less of Fe.
Amorphous alloys as described in section. 6. The amorphous alloy according to claim 5, wherein the other transition metal is Mn. 7 Below: μe (after applying a magnetic field of 4 Oe) − μe (demagnetization) / μe (demagnetization) ×
100 (%) - However, μe is the magnetic permeability measured in a magnetic field of 100 KHz and 2 mOe - when the pulse characteristic deterioration rate is 0 to 1.
-10%, the amorphous alloy according to any one of claims 1 to 6.