JP2001252749A - METHOD FOR PRODUCING Fe-BASE AMORPHOUS RIBBON FOR NANO- CRYSTAL MATERIAL AND METHOD FOR PRODUCING NANO-CRYSTAL MATERIAL - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which an Fe-base amorphous ribbon for nano-crystal material excellent in a magnetic characteristic can continuously and stably be produced without breaking. SOLUTION: In the production of the Fe-base amorphous ribbon for nano- crystal material, having <=10 atomic % boron content, molten is poured on a cooling roll and the solidified Fe-base amorphous ribbon in the temperature range of 100-300 deg.C is detached from the cooling roll. It is desirable that the material contains by atomic % <=15% the total of the components in the 4A, 5A, 6A groups in the periodic table or 0.5-15% Nb desirably 1-10% Nb or 0.1% to <4% Cu or 5-15% Si as the components besides B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an Fe-based amorphous ribbon for use as a nanocrystalline material,
And a method for producing a nanocrystalline material.

[0002]

2. Description of the Related Art As a production method for producing an amorphous ribbon, a liquid quenching method is widely known. As the liquid quenching method, there are a single roll method, a twin roll method, a centrifugal method, and the like, but from the viewpoint of productivity and ease of maintenance,
The single roll method in which a molten metal is supplied onto one cooling roll rotating at high speed and rapidly solidified to obtain a ribbon is excellent.

A nanocrystalline material can be obtained by heat-treating a ribbon produced by such a method. A typical composition of the Fe-based nanocrystalline material is Japanese Patent Publication No. 4-3933.
Fe-Si-B- (Nb, Ti, Hf, M) described in JP-B-7-74419, Japanese Patent No. 2812574, and the like.
o, W, Ta) -Cu alloy, Fe- (Co, Ni) -C
u-Si-B- (Nb, W, Ta, Zr, Hf, Ti,
Mo) alloy, Fe- (Hf, Nb, Zr) -B alloy,
Fe-Cu- (Hf, Nb, Zr) -B alloys and the like are known. The nanocrystalline material has almost no thermal instability found in amorphous alloys, has little change over time, has low magnetostriction and high magnetic permeability, and is therefore used in common mode choke coils, pulse transformers, earth leakage breakers, etc. .

[0004]

When a nanocrystalline material is produced, it is important that the amorphous ribbon before heat treatment, which is a precursor of the nanocrystalline material, has no crystalline phase. This is because the crystal phase formed in the amorphous phase before heat treatment such as during casting is abnormally larger than the crystal phase generated from the amorphous phase by heat treatment, and the structure after heat treatment becomes non-uniform. This is because the magnetic properties are increased and the soft magnetic characteristics are deteriorated. Therefore, in ribbon production, it is important to cool rapidly so as not to crystallize. For this reason, it is desirable to cool the ribbon as quickly as possible during ribbon production.

However, according to the study of the present inventor, there is a problem that if the temperature is excessively cooled, the ribbon is broken during the production and cannot be continuously collected. In addition, since the amorphous ribbon is generally used by being wound in a toroidal shape in many cases, there is a problem in that it is difficult to continuously produce a core if there is a broken portion. An object of the present invention is to provide a method capable of continuously and stably producing an Fe-based amorphous ribbon for a nanocrystalline material having excellent soft magnetic properties without breaking.

[0006]

Means for Solving the Problems The present inventors diligently studied a method for continuously and stably producing an Fe-based amorphous ribbon for a nanocrystalline material with suppressed generation of a crystal phase without breaking. In the production of an amorphous ribbon having a composition in which the B content is 10% or less in terms of%, it has been found that the ribbon temperature at the time of peeling from the cooling roll is extremely important.

That is, the present invention relates to a method for producing an Fe-based amorphous ribbon for a nanocrystalline material containing 10% or less of B in atomic%, wherein a molten Fe-based metal containing 10% or less of B in atomic% is placed on a cooling roll. A method of manufacturing an Fe-based amorphous ribbon for nanocrystalline materials, comprising: releasing the cast and solidified Fe-based amorphous ribbon from the cooling roll in a temperature range of 100 to 300 ° C. The nanocrystalline material in the present invention means a material having a structure having an average crystal grain size of 300 nm or less, preferably an average crystal grain size of 100 nm or less.

From the viewpoint of crystal grain refinement when the ribbon after casting is heat-treated at a temperature higher than the crystallization temperature, B
As a component other than the above, it is preferable to contain a total of 15% or less of 4A, 5A, and 6A groups in atomic%.

Further, Nb is 0.5% to 15%, preferably 1% to 10%, or Cu is 0.1%.
It is preferable that the Si content is not less than 4% and less than 4%, or 5% to 25%.

[0010] Further, the composition of the Fe-based metal melt is atomic%, B is 2% to 10%, Nb is 1% to 5%, Cu is 0.1% to 3%, Si is 10% to 20%. %Less than,
It is more preferable that the balance be substantially Fe, and the thickness of the cast amorphous ribbon be 8 to 25 μm.

In the above, it is preferable that the amorphous ribbon is peeled at a temperature of 100 to 250 ° C. in the cast Fe-based amorphous ribbon.
It is more preferable to carry out at 50 ° C.

A nanocrystalline material can be manufactured by subjecting the Fe-based amorphous ribbon for a nanocrystalline material obtained by the above method to a heat treatment at a temperature not lower than the crystallization temperature of the amorphous ribbon.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, an important feature of the present invention is that the temperature at which an amorphous ribbon having a composition having a B content of 10 at% or less is peeled off from a cooling roll is set to 100 to 100 at%.
That is, the temperature was set to 300 ° C. B is an element that has the effect of improving the ability to form an amorphous phase, and it is preferable that the B level be large to some extent, but it is not preferable that the B level is too large for an Fe-based amorphous ribbon for a nanocrystalline material.

[0014] This post-nanocrystalline materials produced Fe-based amorphous ribbon, is obtained by heat treatment at a crystallization temperature or higher, the magnetic such Fe 3 _B or Fe 2 _B where B amount prevents a significantly greater movement of the magnetic wall This is because a hard compound phase easily precipitates, and it is difficult to obtain a uniform nanocrystalline phase having a bcc-Fe solid solution as a main phase. Therefore, the amount of B is preferably 10 at% or less from the viewpoint of magnetic characteristics. On the other hand, B
Is an element that improves the ability to form an amorphous phase as described above, so it is preferable to add at least 2 at% or more.

However, when the amount of B is less than 10 at%,
The e-base alloy has a low amorphous forming ability, and the obtained amorphous has a very unstable structure. That is, short-range ordering is likely to occur, and this portion is weak in strength. Therefore, in order to continuously produce an amorphous ribbon containing no crystalline phase without breaking, it is necessary to control the peeling temperature.
The reasons for limiting the peeling temperature will be described below.

The reason why the lower limit is set to 100 ° C. is that the peeling temperature is 1
If the temperature is lower than 00 ° C., the ribbon breaks innumerably during the production of the ribbon. Until the ribbon is peeled off, the ribbon is in close contact with the roll, during which time the ribbon is subjected to shrinkage stress due to temperature changes. As described above, the amount of B is 10 at%.
The following Fe-based amorphous alloys are structurally unstable. Therefore, it is considered that the alloy is easily broken by the shrinkage stress as compared with an amorphous alloy having a B content exceeding 10 at%. The ribbon breakage described above is a unique phenomenon that hardly occurs in the Fe-based amorphous ribbon for a nanocrystalline material having a B content exceeding 10 at%, and occurs only in the Fe-based amorphous having a B content of 10 at% or less.

Next, the reason why the upper limit is set to 300 ° C. is that the ribbon becomes brittle at a temperature higher than 300 ° C. The higher the peeling temperature is, the smaller the above-mentioned shrinkage stress is, and the breakage during manufacturing is suppressed. However, if it is too high, embrittlement occurs due to structural relaxation specific to amorphous. This phenomenon is F
An alloy having a B content of 10 at% or less, such as the present invention, is particularly unstable in an amorphous state. Easy to embrittle. In mass production, the ribbon can be several thousand meters, but when the ribbon becomes brittle,
At the time of winding and collecting on reels and handling,
Even if a slight torsional stress is applied, it is easy to break, so it is difficult to handle and inefficient. Therefore, in an alloy having a B content of 10 at% or less, it is necessary to set the upper limit to 300 ° C. in order to prevent this embrittlement phenomenon. The peeling temperature is 100
The temperature is more preferably set to a temperature of from 250 to 250 ° C, and further preferably from 150 to 250 ° C.

The ribbon temperature was measured using a radiation thermometer manufactured by Keyence Corporation. The calibration of the radiation thermometer was performed based on the result of measuring the temperature change of the amorphous ribbon when the plate material was heated by using a thermocouple while the amorphous ribbon was adhered to the plate material of the same material as the cooling roll.

Further, it is preferable to include a group 4A, 5A, or 6A element together with B, since it is effective in refining crystal grains after heat treatment. However, if the added amount of the 4A, 5A, or 6A group element is large, the ribbon after casting becomes brittle, so the added amount is 15 at% or less.

Of the 4A, 5A and 6A group elements, Nb is an element particularly effective when added for the above purpose,
It is preferable to add 0.5% or more and 15% or less. N
When adding b, if the amount is too small, a sufficient effect cannot be obtained, so that 0.5% or more is added. The Nb content is more preferably 1% or more and 10% or less in atomic%, and still more preferably 1% or more and 5% or less.

By adding Cu in addition to Nb,
The number of nucleation sites during the heat treatment increases, and the crystal grains after the heat treatment can be further refined. The addition amount of Cu is set to 0.
If the amount is less than 1 at%, a sufficient effect cannot be obtained. However, if the added amount is large, the ribbon after casting becomes brittle, and Cu and Fe are elements that are easily separated, so if too much, even if the liquid quenching method is used, it is separated from Fe and uniformly dissolved. Since there is also a problem in that it cannot be performed, the content is preferably less than 4 at%.
Preferably it is 3 at% or less.

It is preferable to add Si in an amount of 5 at% or more from the viewpoints of amorphous forming ability and magnetic properties. However, if the addition amount is large, the ribbon becomes brittle, so the content is set to 25 at% or less. Preferably it is 10 at% or more and 20 at% or less.

For each of the above reasons, the composition of the Fe-based metal
2 at% to 10 at%, Nb 1 at% to 5
at% or less, Cu is 0.1 at% or more and 3 at% or less, S
i is 10 at% or more and 20 at% or less, and the balance is substantially Fe
It is preferable that

As described above, the addition amount of B is 10a
If the content is less than t%, the amorphous forming ability is reduced, and the amorphous after casting becomes an unstable structure and becomes brittle. If the sheet thickness is too large, the cooling rate on the roll during casting decreases,
Further embrittlement of the ribbon occurs. Therefore, in the present invention, in order to obtain a sufficient cooling rate on the roll, the plate thickness is set to 25 μm or less. On the other hand, if the ribbon is too thin, holes are formed in the ribbon, making it difficult to produce a sound ribbon. Therefore, the lower limit is set to 8 μm.

By subjecting the Fe-based amorphous ribbon for a nanocrystalline material obtained by the above-described manufacturing method to a heat treatment at a temperature not lower than the crystallization temperature of the amorphous ribbon, the amorphous is nanocrystallized and a nanocrystalline material can be obtained. This heat treatment for nanocrystallization is preferably performed in the range of Tx to Tx + 200 ° C. when the amorphous crystallization temperature is Tx.

[0026]

(Example 1) 1 Cu-3Nb-15.5Si-7B in atomic% using a single roll quenching apparatus shown in FIG.
A ribbon having a composition substantially consisting of the remainder substantially Fe was produced. Ingot of the above-mentioned composition previously melted is placed in crucible 2,
After being melted by high-frequency induction heating, a molten metal was jetted from a nozzle 1 onto a cooling roll 3 made of a Cu-Be alloy and rapidly solidified to produce an amorphous ribbon having a width of 27 mm and a thickness of 19 µm. Here, the outer diameter of the cooling roll is 600
mm, the peripheral speed was 27 m / s, and the ribbon peeling temperature was adjusted by variously changing the temperature of the cooling water flowing in the roll. Peeling was performed with a high-pressure gas jet of nitrogen from the peeling nozzle 5. The evaluation was made based on the presence or absence of breakage during ribbon production and the presence or absence of cracks when a 180 ° bending test described in JIS Z 2248 was performed using the ribbon after production.

Table 1 shows the results. Ribbon peeling temperature is 1
No. lower than 00 ° C. Sample No. 1 was broken when peeled by a high-pressure gas jet. In addition, N exceeding 300 ° C.
o. In No. 5, the ribbon could be manufactured continuously, but cracks occurred in the 180 ° bending test. In addition, No. 2 was heat-treated at 550 ° C., and the result of observing the structure with a transmission electron microscope is shown in FIG. From the figure, it can be seen that the structure is very uniform with an average crystal grain size of 100 nm or less. Also, N
o. The structure of the ribbons 3 and 4 was observed in the same manner, and all of the ribbons had a uniform structure with an average crystal grain size of 30 nm or less.

[0028]

[Table 1]

Example 2 1 Cu-3Mo-15.5Si-8 in atomic% using a single roll quenching apparatus shown in FIG.
B, the balance being substantially composed of Fe and 1 as a comparative example
Cu-3Mo-15.5Si-11B, balance substantially F
e was manufactured. A crucible is charged with an ingot of the above composition previously melted and melted by high-frequency induction heating, and then a molten metal is jetted onto a cooling roll made of a Cu-Be alloy, rapidly cooled and solidified, and has a width of 27 mm and a thickness of 19 μm.
Was manufactured. Here, the outer diameter of the cooling roll was 800 mm, the peripheral speed was 27 m / s, and the ribbon peeling temperature was adjusted by variously changing the temperature of the cooling water flowing in the roll. Peeling was performed with a high pressure gas jet of nitrogen. Evaluation is for the presence or absence of breakage during ribbon production,
The evaluation was performed based on the presence or absence of cracks when the manufactured ribbon was bent at 180 °.

Tables 2 and 3 show the results.
At% amorphous ribbon, if the peeling temperature is lower than 100 ° C, it will break at the peeling position during ribbon production,
When it exceeded 180 °, cracking occurred in the 180 ° bending test. 11
At% amorphous ribbon breaks 1 during manufacturing
No cracking due to 80 ° bending occurred. The ribbon that did not break during production was heat-treated at 550 ° C., and the structure was observed with a transmission electron microscope. In each case, the average crystal grain size was 30 nm or less. A core having an outer diameter of 19 mm and an inner diameter of 15 mm produced by winding this ribbon was heat-treated at the same temperature, and the magnetic permeability at a frequency of 1 kHz was measured.
Although a value of 00000 was obtained, those with a B content of 11 at% were about 50,000 to 60000, which was a very low value as compared with an alloy with a B content of 8 at%.

[0031]

[Table 2]

[0032]

[Table 3]

(Embodiment 3) Using a single roll quenching apparatus as shown in FIG. 1, 7Nb-9B in atomic% and substantially F in the remainder.
e, a ribbon consisting of 2Zr-4Nb-8.5B and the balance substantially consisting of Fe was produced. A crucible is charged with an ingot of the above-mentioned composition previously melted and melted by high-frequency induction heating, and then the molten metal is jetted out while being sealed with an Ar gas on a cooling roll made of a Cu-Be alloy, and rapidly solidified, An amorphous ribbon having a width of 25 mm and a thickness of 19 μm was manufactured. Here, the peripheral speed of the cooling roll was 25 m / s, and the ribbon peeling temperature was adjusted by variously changing the temperature of the cooling water flowing in the roll. Peeling was performed with a high pressure gas jet of nitrogen. The evaluation was based on the presence or absence of breakage during ribbon production.

The results are shown in Tables 4 and 5. As for all alloys having a peeling temperature lower than 100 ° C., the ribbon was broken at the peeling position. The ribbon that did not break during production was heat-treated at 550 ° C., and the structure was observed with a transmission electron microscope. In each case, the average crystal grain size was 50 nm or less.

[0035]

[Table 4]

[0036]

[Table 5]

Example 4 Using a single-roll quenching apparatus as shown in FIG. 1, an ingot having the composition shown in Table 6 previously melted was placed in a crucible and melted by high-frequency induction heating. A molten metal was jetted onto a cooling roll made of a Cu-Be alloy and rapidly solidified to produce a ribbon having a width of 35 mm and a thickness of 17 μm, 20 times for each composition. Here, the outer diameter of the cooling roll is 600 mm, the peripheral speed is 27 m / s,
The ribbon peeling temperature was set to 200 ° C. by changing the temperature of the cooling water flowing in the roll. Peeling was performed with a high-pressure gas jet of nitrogen from the peeling nozzle 5. The evaluation was performed at a rate at which breakage during ribbon production and cracking when the ribbon was bent at 180 ° were performed during 20 times of casting. Table 6
Shows the results. Nb content exceeding 5 at% and
It can be seen that when the amount of Cu exceeds 3 at%, the yield decreases.

[0038]

[Table 6]

Further, in Table 6 where particularly good results were obtained, For the composition of No. 1, using the same manufacturing apparatus, the peeling temperature and the thickness of the ribbon at the time of casting were changed, and the ribbon was manufactured 10 times for each condition. The percentage of ribbons with cracks was investigated. The change in the plate thickness was performed by changing the nozzle size from which the molten metal was jetted.

Table 7 shows the results. Comparing the effect of the thickness at a peeling temperature of 200 ° C., the 27 μm ribbon is very brittle,
In addition to breaking during manufacturing, cracking due to 180 ° bending is also likely to occur. Comparing the influence of the peeling temperature of the ribbon at a plate thickness of 20 μm, it can be seen that when the peeling temperature is 150 to 250 ° C., breakage and the like are particularly unlikely to occur. This peeling temperature is 15
The ribbon at 0 to 250 ° C was heat-treated at 550 ° C, and the structure was observed with a transmission electron microscope. In each case, the average crystal grain size was 30 nm or less.

[0041]

[Table 7]

[0042]

According to the present invention, an Fe-based amorphous ribbon for a nanocrystalline material having a composition with a B content of 10 at% or less can not only be continuously and stably manufactured without breakage but also is not embrittled. The ribbon after production can be continuously collected, and its industrial value is great.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a state of manufacturing an amorphous ribbon according to the present invention.

FIG. 2 is a metal microstructure photograph of an amorphous ribbon according to the present invention after heat treatment.

[Explanation of symbols]

1 nozzle, 2 crucible, 3 cooling roll, 4 amorphous ribbon, 5 peeling nozzle

Claims (10)

[Claims] 1. A method for producing an Fe-based amorphous ribbon for a nanocrystalline material containing 10% or less of B in atomic%, wherein a molten Fe-based metal containing 10% or less of B in atomic% is poured on a cooling roll. The temperature of the solidified amorphous ribbon is 10
A method for producing an Fe-based amorphous ribbon for a nanocrystalline material, comprising separating the amorphous ribbon from the cooling roll in a temperature range of 0 to 300 ° C. 2. The Fe-based metal melt is 4 A, 5 A in atomic%.
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to claim 1, wherein a total of 15% or less of group A and group 6A is contained. 3. The Fe-based metal melt contains Nb in an atomic percentage of 0.1%.
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to claim 1, wherein the content is 5% or more and 15% or less. 4. The Fe-based metal melt contains 1% of Nb in atomic%.
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to claim 3, wherein the content is not less than 10%. 5. The Fe-based metal melt contains Cu at 0.1 atomic%.
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to any one of claims 1 to 4, wherein the content is 1% or more and less than 4%. 6. The Fe-based metal melt contains 5% of Si in atomic%.
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to any one of claims 1 to 5, wherein the content is at least 25% or less. 7. The composition of a Fe-based metal melt, wherein
% To 10%, Nb is 1% to 5%, Cu is 0.1% to 3%, Si is 10% to 20%,
2. The method according to claim 1, wherein the remainder is substantially Fe, and the thickness of the solidified amorphous ribbon is 8 to 25 [mu] m. 8. The temperature of the solidified amorphous ribbon is 1
The method for producing an Fe-based amorphous ribbon for a nanocrystalline material according to any one of claims 1 to 7, wherein the amorphous ribbon is separated from the cooling roll in a temperature range of 00 to 250 ° C. 9. The Fe-based amorphous ribbon for a nanocrystalline material according to claim 8, wherein the solidified Fe-based amorphous ribbon has a temperature in the range of 150 to 250 ° C., and the amorphous ribbon is separated from the cooling roll. Production method. 10. A nanocrystalline material characterized by subjecting an Fe-based amorphous ribbon for a nanocrystalline material obtained by the method according to any one of claims 1 to 9 to a heat treatment at a temperature not lower than the crystallization temperature of the amorphous ribbon. Production method.