JPH0765145B2 - High saturation magnetic flux density Fe-based soft magnetic alloy and high saturation magnetic flux density Fe-based soft magnetic alloy ribbon - Google Patents

Description

TECHNICAL FIELD The present invention relates to a soft magnetic alloy used for magnetic heads, transformers, choke coils, and the like, and in particular, it has a high saturation magnetic flux density and excellent soft magnetic characteristics. Fe-based soft magnetic alloy.

"Prior Art" The characteristics generally required for soft magnetic alloys used in magnetic heads, transformers, choke coils, etc. are as follows: High saturation magnetic flux density.

High magnetic permeability.

Must have low coercive force.

It is easy to obtain a thin shape.

Further, the magnetic head is required to have the following characteristics from the viewpoint of wear resistance in addition to the characteristics described above.

High hardness.

Therefore, when manufacturing a soft magnetic alloy or magnetic head,
From these viewpoints, material research has been conducted in various alloy systems.

Conventionally, crystalline alloys such as sendust, permalloy, and silicon steel have been used for the above-mentioned applications, and recently Fe-based and Co-based amorphous alloys have also been used.

[Problems to be Solved by the Invention] However, in the case of a magnetic head, a more suitable magnetic material for a high-performance magnetic head is desired in order to cope with a high coercive force of a magnetic recording medium accompanying a high recording density. Further, in the case of transformers and choke coils, further miniaturization is required as electronic devices are miniaturized. Therefore, magnetic materials having higher performance are desired.

However, although the sendust has excellent soft magnetic characteristics, it has a low saturation magnetic flux density of about 1.1 T (about 11 KG), and permalloy also has a saturation magnetic flux density of about 10% in a composition having excellent soft magnetic characteristics. It has a low defect of 0.8T (about 8KG). Silicon steel has a high saturation magnetic flux density, but has a defect of poor soft magnetic properties.

On the other hand, among amorphous alloys, Co-based alloys have excellent soft magnetic characteristics, but their saturation magnetic flux density is insufficient at about 1.0 T. Further, the Fe-based amorphous alloy has a high saturation magnetic flux density depending on the composition, and one having a saturation flux density of 1.5 T or more can be obtained. However, the composition system having a high saturation magnetic flux density has insufficient magnetic characteristics.

By the way, looking at the relationship between the magnetic properties of these conventional magnetic materials and the magnetic properties required by practical magnetic devices, transformers often used at a commercial frequency of several tens of KHz often handle large electric power. It is desirable that the saturation magnetic flux density of the core material used for them is as large as possible.

For example, in recent years, pole transformers and the like have been required to have a saturation magnetic flux density of 1.4 T or higher.
Silicon steel with a saturation magnetic flux density of 5T or higher, or 1.
Fe-based amorphous alloys with a saturation magnetic flux density of 3T or more,
It is used despite having an unsatisfactory magnetic permeability.

In such a case, when the magnetic permeability of the magnetic material forming the core material is high, the efficiency as a transformer is improved,
When the above magnetic permeability is obtained, the merit becomes remarkable, but in reality, no practical magnetic material having a magnetic permeability of 1.4 T or more is found.

Further, the usual soft magnetic material is used in a frequency band of several Hz to several hundreds Hz as is well known, but if a soft magnetic material capable of simultaneously achieving high saturation magnetic flux density and magnetic permeability in this range is obtained. It is well known that magnetic parts such as transformers and transformers can be miniaturized and reduced in loss. That is,
The higher the saturation magnetic flux density of the soft magnetic material, the more the magnetic flux increases, and as a result, the volume of the magnetic component can be reduced. Furthermore, since most of the loss of magnetic parts is released to the outside as heat, it is generally necessary to devise a space for other devices and parts, which is a small size of the entire magnetic device equipped with magnetic parts. It was a big obstacle to the change. Therefore, the above problem can be solved by downsizing the magnetic component, and as a result, the entire magnetic device can be downsized.

However, as described above, the conventional soft magnetic material tends to have a low magnetic permeability when it has a high saturation magnetic flux density. Specifically, in a practical Fe-based amorphous alloy, the saturation magnetic flux density is 1.3% or less. If it is ~ 1.5T, the magnetic permeability will be divided by 10,000 to 90
When the magnetic permeability of a practical Co-based amorphous alloy is 10,000 or more, the saturation magnetic flux density is 1.0T.
Tends to divide.

Therefore, there is a demand for a practical soft magnetic material that has both the high saturation magnetic flux density and the high magnetic permeability as described above, and has high mechanical strength and thermal stability.

An object of the present invention is to provide a Fe-based soft magnetic alloy and a soft magnetic alloy ribbon having a high saturation magnetic flux density of 1.4 T or higher and a high magnetic permeability of 10,000 or higher, and having both high mechanical strength and high thermal stability. The purpose is to

"Means for Solving the Problems" The present invention has the following composition in order to solve the above-mentioned problems, has the same or better soft magnetic properties as conventional practical alloys, and high saturation. We succeeded in obtaining an Fe-based soft magnetic alloy having a magnetic flux density, and conceived the present invention.

The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 1 is composed of a composition represented by the following formula in order to solve the above problems, and has a saturation magnetic flux density of 1.4 T or more and a magnetic permeability at 1 kHz. It is at least 10,000 and has a structure in which fine crystal grains are precipitated in an amorphous phase.

(Fe _1-a Q _a ) _b B _x T _y However, Q is either Co or Ni, or both, and T is T
i, Zr, Hf, V, Nb, Ta, Mo, W is one or more elements selected from the group consisting of, and contains either or both of Zr, Hf, a ≦ 0.05 , B ≦ 93 at%, x = 0.5 to 8 at%, y = 4 to 9 at%.

The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 2 is composed of a composition represented by the following formula in order to solve the above-mentioned problems, and has a saturation magnetic flux density of 1.4 T or more and a magnetic permeability at 1 kHz. It is at least 10,000 and has a structure in which fine crystal grains are precipitated in an amorphous phase.

Fe _b B _x T _y However, T is one or more elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo and W, and either Zr or Hf , Or both, and b ≦ 93 atomic%, x = 0.5 to 8 atomic%, and y = 4 to 9 atomic%.

The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 3 is an amorphous alloy obtained by rapidly cooling the fine crystal grains according to claim 1 or 2 from a molten alloy to solve the above problems. It is generated by heat-treating.

The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 4 is the high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 1, 2 or 3 in order to solve the above problems. The value of y that indicates is within the range of 4 <y ≦ 9.

The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 5 forms an alloy ribbon from the high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 1, 2 or 3 in order to solve the above problems. It was done.

The present invention will be described in more detail below.

The high saturation magnetic flux density Fe-based soft magnetic alloy of the present invention comprises a step of rapidly cooling an amorphous alloy or a crystalline alloy containing an amorphous phase having the above composition from a molten metal, and a step obtained by this step. It can be usually obtained by a heat treatment step of heating to precipitate fine crystal grains.

In the present invention, in order to easily obtain the amorphous phase, it is necessary to contain either Zr or Hf having a high amorphous forming ability.
Zr and Hf are part of other 4A-6A group elements, Ti, V,
It can be replaced with Nb, Ta, Mo, W. The reason why Cr is not included here is that Cr is inferior in amorphous forming ability to other elements.

It is considered that B has the effect of increasing the amorphous forming ability of the alloy of the present invention and the effect of suppressing the formation of the compound phase that adversely affects the magnetic properties in the heat treatment step, and therefore addition of B is essential. Like B, Al, Si, C, P and the like are generally used as amorphous forming elements, and the addition of these elements can be regarded as the same as the present invention.

Although the reasons for limiting the alloying elements contained in the high saturation magnetic flux density Fe-based soft magnetic alloy of the present invention have been described above, in order to improve corrosion resistance other than these elements, Cr, Ru and other platinum group elements are added. It is also possible, and if necessary,
Y, rare earth element, Zn, Cd, Ga, In, Ge, Sn, Pb, As, Sb, Bi, Se, Te, L
Magnetostriction can also be adjusted by adding elements such as i, Be, Mg, Ca, Sr, and Ba. Other, inevitable impurities such as H, N, O, S can be regarded as the same as the composition of the high saturation magnetic flux density Fe-based soft magnetic alloy of the present invention even if they are contained to the extent that the desired characteristics are not deteriorated. Of course.

The amount b of Fe, Co and Ni in the alloy of the present invention is 93 atomic% or less. This is because, as will be described later, when b exceeds 93 atom%, a high magnetic permeability cannot be obtained, but in order to obtain a saturation magnetic flux density of 10 kG or more, it is more preferable that b is 75 atom% or more. preferable.

Next, the reasons for limiting the composition of the high saturation magnetic flux density Fe-based soft magnetic alloy of the present invention will be described in detail with reference to examples.

"Example 1" The alloys shown in the following examples were prepared by a single roll liquid quenching method. That is, molten metal is jetted onto the roll by the pressure of argon gas from a nozzle placed on one rotating steel roll, and is rapidly cooled to obtain a ribbon. The width of the ribbon created as described above is about 15 mm, and the thickness is about
It was 20-40 μm.

The magnetic permeability was measured by an inductance method by processing a thin strip into a ring shape with an outer diameter of 10 mm and an inner diameter of 6 mm, winding the stacked pieces. The measurement conditions of effective permeability (μe) are
It was set to 10 mOe and 1 KHz. Saturation magnetic flux density (Bs) is 10kOe in VSM
It was calculated from the magnetization measured in. In the examples described below, magnetic properties are shown after water quenching after holding at a temperature of 600 ° C. or 650 ° C. for 1 hour.

First, the effect of heat treatment on the magnetic properties and structure of the alloy of the present invention will be described below by taking the Fe ₉₁ Zr ₇ B ₂ alloy, which is one of the alloys of the present invention, as an example. The heating rate is 10
The crystallization start temperature of the Fe ₉₁ Zr ₇ B ₂ alloy determined by the differential thermal analysis at ℃ was 480 ℃.

FIG. 1 shows the effect of annealing (water quenching after holding for 1 hour at each temperature) on the effective magnetic permeability of the Fe ₉₁ Zr ₇ B ₂ alloy.

From FIG. 1, the effective magnetic permeability of this alloy in the rapidly cooled state (RQ) shows a low value, but it rapidly increases due to annealing at 500 to 650 ° C. The frequency dependence of the magnetic permeability was examined for a sample with a thickness of about 20 μm after heat treatment at 650 ° C.
It showed excellent soft magnetic characteristics even at high measurement frequencies of 26500, 10KHz19800, and 100KHz of 7800. Moreover, when the effect of the cooling rate on the magnetic permeability was investigated, it was found that
After holding for a period of time, the alloy's effective magnetic permeability of 26500, which was quenched by water quenching, was 18,000 when air-cooled.
The cooling rate after heat treatment is also important.

Therefore, the magnetic properties of the present alloy can be adjusted by appropriately selecting the optimum heat treatment conditions, and the magnetic properties can be improved by annealing in a magnetic field.

Next, the structural change of the Fe ₉₁ Zr ₇ B ₂ alloy before and after heat treatment was investigated by X-ray diffraction method, and the structure after heat treatment was observed with a transmission electron microscope. The results are shown in FIGS. 2 and 3, respectively. .

From Fig. 2, a halo diffraction pattern peculiar to amorphous is observed in the quenched state, and a peculiar diffraction pattern to body-centered cubic is recognized after the heat treatment. It can be seen that the crystals have changed to heart cubic. And the third
From the figure, it can be seen that the structure after heat treatment is composed of fine crystals with a grain size of about 100 to 200Å. In addition, the change in hardness before and after heat treatment of the Fe ₉₁ Zr ₇ B ₂ alloy was examined, and it was found that after the heat treatment at 650 DPN in the quenched state with Vickers hardness at 1400 D after heat treatment
It has also been found that PN is increased to a high value that is not possible with conventional materials and is suitable for magnetic head materials.

As described above, the alloy of the present invention is obtained by crystallizing the amorphous alloy having the above-mentioned composition by heat treatment to obtain a structure mainly composed of ultrafine crystal grains, which has a high saturation magnetic flux density and excellent soft magnetic characteristics, It is possible to obtain excellent properties having higher hardness and high thermal stability.

Next, examples in which the amounts of Zr and B of the alloy are changed will be shown. Table 1, which will be described later, and FIGS. 4, 5, 6, and 7 show the magnetic characteristics after annealing.

From FIG. 4, FIG. 5 and FIG. 6, it can be seen that high permeability and high saturation magnetic flux density are easily obtained in the range of Zr content of 4 to 9 atomic%. Further, if the Zr content is 4 atomic% or less, an effective magnetic permeability of 10,000 or more cannot be obtained, and if it exceeds 9 atomic%, the magnetic permeability sharply decreases and the saturation magnetic flux density also decreases, which is not preferable. Therefore, the limited range of the Zr content in the alloy of the present invention is set to 4 to 9 atom%.

Similarly, regarding the B content, it was found that a high magnetic permeability of 10,000 or more in effective magnetic permeability was easily obtained in the range of 0.5 to 8 atomic%, and therefore the limited range of the B content was set to 0.5 to 8 atomic%. Further, even if the amount of Zr, B is in the above range, high magnetic permeability cannot be obtained when the amount of Fe exceeds 93 atomic%, so
The Fe content was 93 atomic% or less.

"Example 2" Next, the Fe-Hf-B-based alloy obtained by substituting Hf for Zr in the Fe-Zr-B-based alloy shown in Example 1 will be described.

As an example, Table 2 below shows the results when the Hf content of the Fe-Hf-B system alloy was changed in the range of 4 to 9 atomic%.

It can be seen from Table 2 that the effective magnetic permeability of the Fe-Hf-B alloy is equivalent to that of the Fe-Zr-B alloy in the range of 4 to 9 atomic%. The magnetic characteristics of the Fe ₉₁ Zr ₄ Hf ₃ B ₂ alloy shown in Table ₂ are equivalent to those of the Fe—Zr—B alloy of Example 1. Therefore, Zr of the Fe-Zr-B-based alloy shown in Example 1 can be partially or completely replaced with Hf in all 4 to 9 atomic% which is the composition limiting range.

"Example 3" Next, Fe- (Zr, Hf)-shown in Examples 1 and 2 was used.
A case where a part of Zr and Hf of the B alloy is replaced with Nb will be described.

As an example, Table 3 shows the results when a part of Zr of the Fe-Zr-B alloy was replaced with 1 to 5 atomic% of Nb.

From Table 3, the amount of Zr + Nb that is easy to obtain high magnetic permeability is Fe-Zr.
-The amount is 4-9 atom%, which is the same as the amount of Zr in B alloys, and Nb is Zr.
It can be seen that it has the same addition effect as. Therefore, Fe
A part of Zr, Hf of the (Zr, Hf) -B alloy can be replaced with Nb.

[Example 4] Next, Nb of the Fe- (Zr, Hf) -Nb-B alloy was changed to Ti, V, Ta, Mo, W.
The case of replacing with will be described. As an example, Fe-Zr-TB (T = Ti, V, Ta, Mo, W) is shown in Table 4 below.
The magnetic characteristics of the alloys are shown.

In each of the examples in Table 3, the effective magnetic permeability which is usually obtained with the Fe-based amorphous alloy exceeds 5000, and some of them show a value higher than that, that is, excellent magnetic permeability exceeding 10,000. There is.
Therefore, Nb of the Fe- (Zr, Hf) Nb-B alloy is Ti, V, Ta, Mo, W.
Can be replaced with.

Example 5 Next, the reasons for limiting the Co and Ni contents in the alloy of the present invention will be described. As an example, FIG. 8 shows the relationship between the magnetic permeability and the amounts (a) of Co and Ni of (Fe _1-a Q _a ) ₉₁ Zr ₇ B ₂ alloy (Q = Co, Ni).

In FIG. 8, when a is 0.05 or less, a high value of effective magnetic permeability of 10,000 or more is shown, but in the range of 0.05 or more, the effective magnetic permeability sharply decreases, which is not preferable in practice. Therefore, Co and Ni contents in the alloy of the present invention (a)
Was 0.05 or less.

"Effects of the Invention" As described above, according to the present invention, it was impossible to combine the conventional practical alloys, since it has a saturation magnetic flux density of 1.4T or more and a magnetic permeability of 10,000 or more, the alloy of the present invention and Thin ribbons are required for high coercive force of magnetic recording media, and for magnetic heads that require high magnetic permeability, or transformers and choke coils for which further size reduction and weight reduction are desired. Is suitable as

That is, the soft magnetic alloy and the ribbon of the present invention have saturation magnetic flux density
Since it is 1.4T or more and the magnetic permeability is 10,000 or more, when compared with conventional materials, it should be used in magnetic parts for magnetic heads, transformers, choke coils, etc. to improve efficiency in any case. At the same time, low loss can be realized, which contributes to reduction in size and weight of a magnetic device using those magnetic parts and reduction in loss.

Further, since the soft magnetic alloy and the ribbon of the present invention have high mechanical strength and high thermal stability, they are useful as magnetic heads, transformers, choke coils, etc. If the mechanical strength is high,
It is possible to provide a material having excellent thermal stability.

Further, in the present invention, the structure in which fine crystal grains are precipitated in the amorphous phase is easily obtained by rapidly cooling the molten alloy to generate an amorphous phase and subjecting this amorphous phase to heat treatment. By precipitating these fine crystal grains in the amorphous phase, both excellent soft magnetic characteristics and high saturation magnetic flux density are exhibited.

Furthermore, if it is a ribbon made of a soft magnetic alloy having the composition and structure according to the present invention, it can be easily laminated and can be easily applied as a core material of a magnetic head or a core material of a transformer. .

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between effective magnetic permeability and annealing temperature of an example of the alloy of the present invention, FIG. 2 is a graph showing an X-ray diffraction pattern showing the structural change before and after heat treatment of an example of the alloy of the present invention, and FIG. Is a schematic diagram of a micrograph showing a structure of an example of the alloy of the present invention after heat treatment, and FIG. 4 is a magnetic permeability when Zr content, B content and Fe content are changed in an example of the alloy of the present invention heat treated at 600 ° C. FIG. 5 is a triangular composition diagram showing the magnetic permeability when Zr content, B content and Fe content are changed in an example of the alloy of the present invention heat-treated at 650 ° C., and FIG. 6 is an alloy of the present invention. In one example, a triangular composition diagram showing the saturation magnetic flux density when Zr amount, B amount and Fe amount are changed, FIG. 7 is a triangular composition diagram showing the Ds value of the same alloy, and FIG. 8 is an example of the alloy of the present invention. 5 is a graph showing the relationship between the Co amount and magnetic permeability in FIG.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noriyuki Kataoka 1-4-7 Mukoyama, Aoba-ku, Sendai-shi, Miyagi 2nd Highness 212 Mukoyama (56) Reference JP-A-63-236304 (JP, A) ) JP-A 64-28343 (JP, A) JP-A 2-123705 (JP, A) JP-A 4-99253 (JP, A)

Claims (5)

[Claims] 1. A composition having a composition represented by the following formula, a saturation magnetic flux density of 1.4 T or more, a magnetic permeability at 1 kHz of 10,000 or more, and a structure in which fine crystal grains are precipitated in an amorphous phase. Fe-based soft magnetic alloy with high saturation magnetic flux density. (Fe _1-a Q _a ) _b B _x T _y However, Q is either Co or Ni, or both, and T
Is one or more elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo, W, and any one of Zr, Hf,
Or including both, a ≦ 0.05, b ≦ 93 atomic%, x = 0.5 to
8 atom% and y = 4 to 9 atom%. 2. A composition represented by the following formula, having a saturation magnetic flux density of 1.4 T or more, a magnetic permeability of 10000 or more at 1 kHz, and having a structure in which fine crystal grains are precipitated in an amorphous phase. Fe-based soft magnetic alloy with high saturation magnetic flux density. Fe _b B _x T _{y where} T is one or more elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo and W, and either Zr or Hf , Or both, b ≦ 93 atomic%, x = 0.5 to 8
Atomic% and y = 4 to 9 atomic%. 3. The high saturation magnetic flux density according to claim 1 or 2, wherein the fine crystal grains are generated by heat-treating an amorphous alloy obtained by quenching the molten alloy. Fe-based soft magnetic alloy. 4. The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 1, 2 or 3, characterized in that the value of y showing the atomic% of T is in the range of 4 <y ≦ 9. High saturation magnetic flux density Fe-based soft magnetic alloy. 5. A high-saturation-flux-density Fe-based soft magnetic alloy ribbon characterized by comprising the high-saturation-flux-density Fe-based soft-magnetic alloy according to claim 1, 2, 3 or 4.