JPH06128704A - High saturation magnetic flux density Fe-based soft magnetic alloy - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a soft magnetic alloy having a high saturation magnetic flux density and excellent soft magnetic properties. [Structure] The alloy of the present invention is (Fe _1- a Co a) b Bx
Ty composition, Fe bBx Ty composition, (Fe _1- a C
oa) b Bx Ty Qs X composition or Feb
It has a composition of Bx Ty Qs X. However, T
Is one or more of Ti, Nb, Ta, Q is one or more of Zr and Hf, X is Cr, Mo, W, Ru, Rh, Ir, etc.
≦ 0.05, b ≦ 92 at%, x = 6.5-18 at%, y
= 4 to 10 atom%, and s = 4 to 10 atom%. The soft magnetic alloy of the method of the present invention has excellent magnetic permeability at high frequencies, excellent mechanical strength, and excellent heat resistance. Therefore, it is suitable for magnetic heads, choke coils, transformers and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soft magnetic alloy used for magnetic heads, transformers, choke coils and the like, and more particularly to a Fe-based soft magnetic alloy having a high saturation magnetic flux density and excellent soft magnetic characteristics.

[0002]

2. Description of the Related Art The characteristics generally required for soft magnetic alloys used for 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, regarding the magnetic head,
In addition to the characteristics described in (1), the following characteristics are required from the viewpoint of wear resistance. High hardness.

Therefore, when manufacturing a soft magnetic alloy or a magnetic head, various alloy systems have been studied from these viewpoints. Conventionally, for the aforementioned applications,
Crystalline alloys such as sendust, permalloy, and silicon steel are used, and recently Fe-based and Co-based amorphous alloys have also been used.

[0005]

In the case of a magnetic head, however, a more suitable magnetic material for a high-performance magnetic head is desired in order to cope with the increase in coercive force of the magnetic recording medium accompanying the increase in 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 drawback that the saturation magnetic flux density is as low as about 11 KG. Similarly, permalloy has a saturation magnetic flux density of about 10 kg in an alloy composition having excellent soft magnetic characteristics. It has a low defect of 8 KG, and silicon steel has a high saturation magnetic flux density but a poor soft magnetic property.

On the other hand, among the amorphous alloys, the Co-based alloy is excellent in soft magnetic characteristics, but the saturation magnetic flux density is insufficient at about 10 KG. Further, the Fe-based alloy has a high saturation magnetic flux density and can have a magnetic flux density of 15 KG or more, but the soft magnetic characteristics are insufficient. Further, the thermal stability of the amorphous alloy is not sufficient, and there are still unsolved aspects. As mentioned above, it is difficult to combine high saturation magnetic flux density with excellent soft magnetic characteristics.

Furthermore, the inventors of the present invention filed Japanese Patent Application No. 2-23 on Aug. 31, 1990 as an advanced alloy of the above alloy.
No. 0135 has filed a patent application for an alloy having the following composition.

One of the alloys according to this patent application was a high saturation magnetic flux density alloy characterized by having a composition represented by the following formula. (Fe _1- a Ma) b Bx Ty where M is 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 Zr, Hf, and contains either or both, and a ≦ 0 0.05, b ≦ 93 atomic%, x
= 0.5 to 8 atom% and y = 4 to 9 atom%.

Further, another one of the alloys according to the above patent application is a high saturation magnetic flux density alloy characterized by having a composition represented by the following formula. Fe b Bx Ty, where b ≦ 93 at%, x = 0.5 to 8 at%, y = 4 to
It is 9 atom%.

The object of the present invention is to develop a soft magnetic alloy of the above-mentioned patent application to make it easy to manufacture, and to have a high saturation magnetic flux density and a high magnetic permeability, and to have a high mechanical strength and a high thermal stability. It is to provide a magnetic alloy.

[0012]

The soft magnetic alloy according to the present invention has a composition represented by the following formula in order to solve the above problems. (Fe _1- a Ma) b Bx Ty where M is either Co or Ni or both, and T
Is one or more elements selected from Ti, Nb and Ta, and a ≦ 0.05, b ≦ 93 atomic%, x = 6.
It is 5 to 10 atomic% and y = 4 to 9 atomic%.

In order to solve the above-mentioned problems, the soft magnetic alloy according to claim 2 has a composition represented by the following formula. Fe b Bx Ty where T is one or more elements selected from Ti, Nb and Ta, and b ≦ 93 atomic%, x = 6.5 to 10 atomic%, y = 4 to It is 9 atom%.

In order to solve the above-mentioned problems, the soft magnetic alloy according to claim 3 has a composition represented by the following formula. (Fe _1- a Ma) b Bx Ty Qs X where M is either Co or Ni, or both, and T
Is one or more elements selected from Ti, Nb, Ta, Q is at least one of Zr and Hf, and X is Cr, Mo, W, Ru, Rh, Ir. It is an element selected from among a ≦ 0.05, b ≦ 93 atom%, x = 6.
5 to 10 atomic%, y = 4 to 9 atomic%, and s = 4 to 10 atomic%.

In order to solve the above-mentioned problems, the soft magnetic alloy according to claim 4 has a composition represented by the following formula. Fe b Bx Ty Qs X where T is one or more elements selected from Ti, Nb and Ta, Q is at least one of Zr and Hf, and X is Cr, Mo, An element selected from W, Ru, Rh, and Ir, b ≦ 93 atomic%, x = 6.5 to 1
0 atomic%, y = 4 to 9 atomic%, and s = 4 to 10 atomic%.

A high saturation magnetic flux density Fe-based soft magnetic alloy according to a fifth aspect of the present invention is provided for solving the above problems.
Alternatively, the soft magnetic alloy described in 4 is heat-treated.

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 is obtained by quenching an amorphous alloy having the above composition or a crystalline alloy containing an amorphous phase from a molten metal, and a sputtering method or vapor deposition method. It can usually be obtained by the steps of obtaining by the phase quenching method and the heat treatment step of heating the material obtained in these steps to precipitate fine crystal grains.

In the present invention, in order to easily obtain an amorphous phase, it is necessary to contain at least one of Ti, Nb and Ta having an amorphous forming ability and B.

It is considered that B has an effect of enhancing the amorphous forming ability of the alloy of the present invention and an effect of suppressing the formation of a compound phase which adversely affects the magnetic properties in the heat treatment step. Therefore, addition of B is essential. Is. Same as B, A1, S
i, C, P and the like are also commonly used as amorphous forming elements, and the addition of these elements can be regarded as the same as the present invention.

Although Ti, Nb and Ta have the same effect,
Among these elements, Nb and Ta are metallic materials having a high melting point, are thermally stable, and are difficult to oxidize during manufacturing. Therefore, when these elements are added, the manufacturing conditions are easier and can be manufactured at a lower cost than those containing Hf or Zr in the material for which the inventors of the present invention have previously applied for a patent. It is also advantageous in terms of cost. That is, in the alloy of the system for which the present inventors have applied for a patent, it was necessary to produce while paying attention to oxidation by supplying an inert gas in a vacuum atmosphere, but in the alloy of the present invention, Manufacturing conditions can be relaxed. Specifically, it becomes possible to manufacture in the atmosphere or in the atmosphere while partially supplying the inert gas to the tip of the nozzle.

The reasons for limiting the alloying elements contained in the soft magnetic alloy of the present invention have been described above. However, in order to improve the corrosion resistance other than these elements, Cr, Mo, or Ru, Rh, I are added.
It is also possible to add platinum group elements such as r, and if necessary, Y, rare earth elements, Zn, Cd, Ga, In, G
e, Sn, Pb, As, Sb, Bi, Se, Te, Li, Be, Mg, Ca, Sr,
Magnetostriction can also be adjusted by adding an element such as Ba. In addition, inevitable impurities such as H, N, O, and 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 desired characteristics are not deteriorated. Of course.

Fe, Co, and Ni content of b in the alloy of the present invention
Is 93 atomic% or less. This is because when b exceeds 93 atom%, high magnetic permeability cannot be obtained, but in order to obtain a saturation magnetic flux density of 10 kG or more, b is preferably 75 atom% or more.

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.

[0024]

Example 1 The alloys shown in the following examples were prepared by the 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 produced as described above was about 15 mm and the thickness was about 20 to 40 μm.

The magnetic permeability was measured by an inductance method by processing a thin ribbon into a ring shape having an outer diameter of 10 mm and an inner diameter of 5 mm, winding the stacked pieces, and winding them. Effective permeability (μ
The measurement conditions of e) were 10 mOe and 1 kHz. Coercive force (Hc)
Was measured with a DC BH loop tracer, and the saturation magnetic flux density (Bs) was calculated from the magnetization measured with VSM at 10 kOe. Unless otherwise specified, the following examples show magnetic characteristics after water quenching after holding at a temperature of 500 to 700 ° C. for 1 hour.

First, the effect of heat treatment on the magnetic properties and structure of the alloy of the present invention is one of the alloys of the present invention, F.
A description will be given below by taking an e ₈₄ Nb ₇ B ₉ alloy as an example. The crystallization start temperature of the alloy was 490 ° C., which was determined by a differential thermal analysis at a heating rate of 10 ° C./min.

FIG. 1 shows the effect of annealing (holding at each temperature for 1 hour and then water quenching) on the effective magnetic permeability of the alloy having the above composition.

As shown in FIG. 1, the effective magnetic permeability of the present alloy in the rapidly cooled state (RQ) is as low as that of the Fe-based amorphous alloy, but is rapidly increased by the annealing at 500 to 620 ° C. Here, when the frequency dependence of magnetic permeability was examined for a sample having a thickness of about 20 μm after heat treatment at 600 ° C., 1
13500 kHz, 12000 at 10 kHz, 1 more
It exhibited excellent soft magnetic characteristics even at a high measurement frequency of 6000 at 00 kHz. Therefore, the magnetic properties of the alloy of the present invention can be adjusted by appropriately selecting the optimum heat treatment conditions, and the magnetic properties can be improved by annealing in a magnetic field.

FIG. 2 shows the results of measuring the effect of the B content on the effective magnetic permeability of the alloy of composition Fe _93- xNb ₇ Bx. In FIG. 2, the change in magnetic permeability was measured by increasing or decreasing the content of B in the range of 6 to 10%.

From FIG. 2, it was found that the B content shows excellent magnetic permeability in the range of 6.5 to 10 atom%.
Therefore, in the present invention, the B content is limited to 6.5 to 10%.

Next, the structural change of the Fe _93- xNb ₇ Bx alloy before and after the heat treatment was examined by an X-ray diffraction method, and the structure after the heat treatment was observed with a transmission electron microscope. The results are shown in FIGS. 3 and 4, respectively. Show.

From FIG. 3, a halo diffraction pattern peculiar to amorphous is observed in the quenched state, and a diffraction pattern peculiar to crystalline is recognized after the heat treatment.
It can be seen that the material changed from amorphous to crystalline. From FIG. 4, it can be seen that the structure after heat treatment is composed of fine crystals having a grain size of about 100 to 200 angstroms. The change in hardness of the Fe ₈₄ N _b7 B ₉ alloy before and after the heat treatment was also examined, and it was found that it was 950D in the rapidly cooled state with Vickers hardness.
It was also found that after the heat treatment at 650 ° C. from PN, it increased to a high value of 650 DPN, which was suitable for a magnetic head material.

As described above, according to the alloy of the present invention, the amorphous alloy having the above-mentioned composition is crystallized by the heat treatment to obtain a structure mainly composed of ultrafine crystal grains, so that a high saturation magnetic flux density and a soft magnetic flux are obtained. It is possible to obtain excellent magnetic properties as well as high hardness and high thermal stability. Moreover, Ta and Nb, which are the elements mainly used in the alloy of the present invention, are refractory metals, are resistant to heat, and are less likely to oxidize during production, so that they are more producible than the alloys that the present inventors have previously applied for patents. It is characterized by mild conditions and easy manufacture.

Next, the Fe content and B of the soft magnetic alloy according to the present invention.
The change in magnetic permeability was measured when the amount of Nb and the amount of Nb were increased and decreased, and the results are shown in FIG.

In FIG. 5, the range in which the magnetic permeability is superior to the value around 10,000 is 4 to 4 in the Nb amount.
It is clear that the content of 9 atomic% and the amount of B is 6.5 to 10 atomic%.

Next, the Fe content and B of the soft magnetic alloy according to the present invention.
The change in the saturation magnetic flux density when the amount of Nb and the amount of Nb were increased and decreased was measured, and the results are shown in FIG.

From FIG. 6, it was found that excellent values of 1.3 to 1.5 T (Tesla) were obtained in the alloy composition range of the present invention.

Next, the reasons for limiting the Co and Ni contents in the alloy of the present invention will be described. As an example, (Fe _1- a
M a) ₈₄ N _b7 B ₉ alloy (M = Co, the relationship between the Co amount and the Ni amount and the permeability of Ni) shown in FIG. In FIG. 9, a
Is less than 0.05, the effective permeability is 1000
A high value of 0 or more is shown, but if it exceeds 0.05, the magnetic permeability sharply decreases, which is not preferable. Therefore, in the present invention, the contents of Co and Ni are limited to 0.05.

Next, the Fe-Nb-B-Cu based alloys described above in which Nb is replaced by Ta are replaced by Fe-Ta-B-Cu based alloys and the Fe-Ti-B-Cu alloys in which Nb is replaced by Ti. System alloy and Nb Ta and Ti
Fe-Ta-Ti-B-Cu-based alloys substituted by Fe, Fe-Nb-Ta-B-Cu-based alloys in which Nb is replaced by a plurality of elements, and Fe-Nb-T
Examples of a-Ti-B-Cu alloys are shown in Table 1, which will be described. (Hereafter, margin)

[0040]

[Table 1]

From the results shown in Table 1, the same degree of magnetic permeability and saturation magnetic flux density were obtained for the alloys of each composition.

From the above results, it is possible to replace Nb in the Fe-Nb-B-Cu system alloy with Ta and Ti, and to replace Nb with Nb.
It has been found that it is possible to replace Nb with Ta and Ti, or Nb with Ta and Ti, or Nb with Nb, Ta and Ti.

As is clear from the above description of the examples, the soft magnetic alloy of the present invention has a high magnetic permeability of more than 10,000, an excellent saturation magnetic flux density of about 15 kG, excellent heat resistance and hardness. It is high and excellent.

Therefore, the soft magnetic alloy of the present invention is suitable for magnetic heads, transformers, and choke coils, and when used for these applications, it is possible to improve their performance, reduce their size, and reduce their weight. There is.

As described above, according to the present invention, there is provided a Fe-based soft magnetic alloy having the same or better soft magnetic characteristics as the conventional practical alloys and also having a higher saturation magnetic flux density. can do. Moreover, the soft magnetic alloy of the present invention has high mechanical strength and high thermal stability. In addition, N which is a main constituent element in the alloy of the present invention
Since b and Ta are both thermally stable elements, they are less likely to be deteriorated by an oxidation reaction or a reduction reaction at the time of production and have an advantage that the conditions at the time of production are advantageous. From the above, the soft magnetic alloy of the present invention is suitable for a magnetic head that needs to be compatible with a high coercive force of a magnetic recording medium, a transformer that is required to be further downsized, and a choke coil. When used for these purposes, it is possible to improve the performance and reduce the size and weight.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the cooling temperature and the magnetic permeability of an example of the alloy of the present invention.

FIG. 2 is a graph showing the relationship between effective magnetic permeability and B content of an example of the alloy of the present invention.

FIG. 3 is a graph showing an X-ray diffraction pattern showing a structural change associated with heat treatment of an example of the alloy of the present invention.

FIG. 4 is a schematic view of a micrograph showing the structure of an example alloy of the present invention after heat treatment.

FIG. 5 is a triangular composition diagram showing the magnetic permeability when the Fe amount, the B amount and the Nb amount are changed in an example of the alloy of the present invention.

FIG. 6 is a graph showing the relationship between the saturation magnetic flux density when the Fe amount, the B amount and the Nb amount are changed in an example of the alloy of the present invention.

FIG. 7 is a graph showing the relationship between Cu content and magnetic permeability in an example of the alloy of the present invention.

Front page continuation (72) Inventor Ken Masumoto 3-8-22, Uesugi, Aoba-ku, Sendai-shi, Miyagi (72) Akihisa Inoue Kawauchi Muzenchi, Kawauchi, Aoba-ku, Sendai-shi, Miyagi 11-806

Claims (5)

[Claims] 1. A high saturation magnetic flux density Fe-based soft magnetic alloy having a composition represented by the following formula. (Fe _1- a Ma) b Bx Ty where M is either Co or Ni or both, and T
Is one or more elements selected from Ti, Nb and Ta, and a ≦ 0.05, b ≦ 93 atomic%, x = 6.5 to 10 atomic%, y = 4 to It is 9 atom%. 2. A high saturation magnetic flux density Fe-based soft magnetic alloy having a composition represented by the following formula. Fe b Bx Ty where T is one or more elements selected from Ti, Nb and Ta, and b ≦ 93 atomic%, x = 6.5 to 10 atomic%, y = 4 to It is 9 atom%. 3. A high saturation magnetic flux density Fe-based soft magnetic alloy having a composition represented by the following formula. (Fe _1- a Ma) b Bx Ty Qs X where M is either Co or Ni, or both, and T
Is one or more elements selected from Ti, Nb, Ta, Q is at least one of Zr and Hf, and X is Cr, Mo, W, Ru, Rh, Ir. An element selected from among a ≦ 0.05, b ≦ 93 atomic%, x = 6.5 to 10 atomic%,
y = 4 to 9 atom%, and s = 4 to 10 atom%. 4. A high saturation magnetic flux density Fe-based soft magnetic alloy having a composition represented by the following formula. Fe b Bx Ty Qs X where T is one or more elements selected from Ti, Nb and Ta, Q is at least one of Zr and Hf, and X is Cr, Mo, An element selected from W, Ru, Rh, and Ir, b ≦ 93 atom%, x = 6.5 to 10 atom%, y = 4 to 9
Atomic%, s = 4 to 10 atomic%. 5. The high saturation magnetic flux density Fe-based soft magnetic alloy according to claim 1, 2, 3 or 4, which is heat-treated.