JP6709839B2 - Method of manufacturing nanocrystalline alloy ribbon - Google Patents

Description

The present invention relates to a method of manufacturing a nanocrystalline alloy ribbon.

Magnetic materials used in transformers, reactors, choke coils, motors, noise suppression components, laser power supplies, pulse power magnetic components for accelerators, generators, etc. are silicon steel, ferrite, Fe-based amorphous alloys, Fe-based nanocrystalline alloys, etc. It has been known.

Of these, Fe-based nanocrystalline alloys tend to have a smaller magnetic core loss than silicon steel, and tend to have a higher saturation magnetic flux density than ferrite and Fe-based amorphous alloys.
The following alloys are known as Fe-based nanocrystalline alloys, for example.
As magnetic alloy having high saturation magnetic flux density and low core losses, by the composition formula _{Fe 100-x-y Cu x} B y [wherein, x and y are both atomic%, respectively, 0.1 ≦ x ≦ 3 , and 10 ≦ satisfies the condition y ≦ 20] or formula _{Fe 100-x-y over} z _Cu x _B y _{X z} [wherein, x, y and z are both atomic%, respectively, 0. The conditions of 1≦x≦3, 10≦y≦20, 0<z≦10, and 10<y+z≦24 are satisfied. X is at least one element selected from the group consisting of Si, S, C, P, Al, Ge, Ga, and Be. ] A magnetic alloy is known which has a composition represented by the following formula, has a structure in which crystal grains having an average grain size of 60 nm or less are contained in an amorphous matrix, and has a saturation magnetic flux density of 1.7 T or more ( See, for example, Patent Document 1 below.

Further, as a method for producing a soft magnetic alloy having a saturation magnetic flux density of 1.7 T or more, a small coercive force, and a small hysteresis loss and a high saturation magnetic flux density and a low coercive force, the composition formula is Fe _100-x-y-z. represented by a _x M _{y X z,} wherein, a is selected at least one element selected from Cu and Au, M is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and the W At least one element, X is at least one element selected from B and Si, and in atomic %, 0<x≦5, 0.4≦y<2.5, 10≦z≦20. And a step of rapidly cooling the molten alloy to cast a substantially amorphous alloy, and thereafter performing a heat treatment so that the average heating rate in a temperature range of 300° C. or higher becomes 100° C./min or higher. A manufacturing method of a soft magnetic alloy containing is known (for example, refer to Patent Document 2 below).

Table Further, as a method for producing stably excellent soft alloy is toughness low coercivity be a high saturation magnetic flux density, composition formula by _{Fe 100-x-y-z} A x M y X z P a Where A is at least one element selected from Cu and Au, M is at least one element selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W, X is at least one element selected from B and Si, and in atomic %, 0.5≦x≦1.5, 0≦y≦2.5, 10≦z≦23, 0.35≦a A step of casting a molten alloy of ≦10 into a substantially amorphous ribbon shape having a thickness of 100 μm or less, and thereafter, an average heating rate in a temperature range of 300° C. or higher is 100° C./min or higher. To form a soft magnetic ribbon having a structure in which crystal grains having a crystal grain size of 60 nm or less (not including 0) are dispersed in an amorphous phase by 30% or more by volume fraction. A method for manufacturing a ribbon is known (for example, refer to Patent Document 3 below).

As a method for treating the amorphous alloy ribbon, a) feed the amorphous alloy ribbon forward along a traveling path at a set feed speed, tension it, and guide it; b) move the amorphous alloy ribbon along the traveling path. At a temperature of more than 10 ³ °C/sec at a temperature to start the heat treatment; c) cooling the amorphous alloy ribbon at a rate of more than 10 ³ °C/sec until the heat treatment is finished; d) the heat treatment And a) applying a series of mechanical constraints to the ribbon after the heat treatment, until the amorphous alloy ribbon takes a specific shape in a stationary state; and e) after the heat treatment, the amorphous alloy ribbon at a rate that preserves the specific shape. A method including a cooling step is known (see, for example, Patent Document 4).

Patent Document 1: International Publication No. 2007/032531 Patent Document 2: International Publication No. 2008/133301 Patent Document 3: International Publication No. 2008/133302 Patent Document 4: International Publication No. 2011/060546

The study by the present inventors has revealed that when a heat treatment is performed on an amorphous alloy ribbon to produce a nanocrystalline alloy ribbon, waviness or wrinkles may occur in the produced nanocrystalline alloy ribbon. Hereinafter, the nanocrystalline alloy ribbon may be simply referred to as “ribbon”, and the swell or wrinkle that may occur in the nanocrystalline alloy ribbon may be referred to as “ripple”.
Further, it has been found that the ribbon having ripples may have a reduced space factor when the ribbons are laminated.
Further, since the nanocrystalline alloy ribbon is at least partially crystallized, the toughness is lower than that of the amorphous alloy ribbon before heat treatment. Therefore, if pressure is applied to suppress the ripple, the ribbon may be broken.

From the above viewpoints, it is desired to provide a method for producing a nanocrystalline alloy ribbon capable of producing a nanocrystalline alloy ribbon in which the generation of ripples is suppressed.

Specific means for solving the above problems include the following aspects.
<1> A step of preparing an amorphous alloy ribbon having a composition represented by the following composition formula (A):
The amorphous alloy ribbon is continuously run under tension F, and a partial region of the amorphous alloy ribbon continuously running under tension F is applied to a heat transfer medium maintained at a temperature of 450° C. or higher. By bringing them into contact with each other under the condition satisfying the following formula (1), the temperature of the amorphous alloy ribbon is 450° C. or more at a heating rate such that the average heating rate in the temperature range from 350° C. to 450° C. is 10° C./sec or more. To obtain a nanocrystalline alloy ribbon by raising the temperature reached to
A method for manufacturing a nanocrystalline alloy ribbon containing:
_{Fe 100-a-b-c} -d B a Si b Cu c M d ... formula (A)
[In the composition formula (A), a, b, c, and d are all atomic %, and 0<a, 0<b, 0<c, 0≦d, and 78≦100-a, respectively. -B-c-d is satisfied. M represents at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. ]
t _c >4/σ Equation (1)
[In Formula (1), t _c represents the time (seconds) from the time when any one point of the amorphous alloy ribbon comes into contact with the heat transfer medium to the time when the one arbitrary point separates from the heat transfer medium. σ represents a contact pressure (kPa) between the amorphous alloy ribbon and the heat transfer medium, which is defined by the following formula (X). ]
σ=((F×(sin θ+sin α))/a)×1000 Formula (X)
[In Formula (X), F represents a tension (N) applied to the amorphous alloy ribbon.
a represents a contact area (mm ² ) between the amorphous alloy ribbon and the heat transfer medium.
θ is an angle formed by the running direction of the amorphous alloy ribbon immediately before contact with the heat transfer medium and the running direction of the amorphous alloy ribbon when in contact with the heat transfer medium, and is 3°. It represents an angle of not less than 60°.
α is an angle formed by the traveling direction of the amorphous alloy ribbon when in contact with the heat transfer medium and the traveling direction of the nanocrystalline alloy ribbon immediately after being separated from the heat transfer medium, and 0 It represents an angle of more than 15° and less than 15°. ]

<2> The method for producing a nanocrystalline alloy ribbon according to <1>, wherein the σ is 0.1 kPa or more.
<3> The method for producing a nanocrystalline alloy ribbon according to <1> or <2>, wherein the σ is 0.4 kPa or more.
<4> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <3>, wherein the t _c is 300 seconds or less.
<5> The method for producing a nanocrystalline alloy ribbon according to any one of <1> to <4>, wherein c is 0.5 or more and 1.2 or less in the composition formula (A).
<6> In the composition formula (A), the a is 10.0 or more and 20.0 or less, and the b is more than 0 and 10.0 or less, according to any one of <1> to <5>. Of manufacturing a nanocrystalline alloy ribbon of.

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the nanocrystal alloy ribbon which can manufacture the nanocrystal alloy ribbon in which the generation|occurrence|production of a ripple was suppressed is provided.

1 conceptually shows a heat transfer medium of an in-line annealing apparatus and an amorphous alloy ribbon (a nanocrystalline alloy ribbon after contact with the heat transfer medium) in contact with the heat transfer medium according to one aspect of an embodiment of the present invention. It is a partial side view.

Hereinafter, embodiments of the present invention will be described.
In the present specification, the numerical range represented by using "to" means a range including the numerical values before and after "to" as the lower limit value and the upper limit value.
Further, in the present specification, the term “process” is not limited to an independent process, and even if the process is not clearly distinguishable from other processes, the term is used as long as the intended purpose of the process is achieved. include.
Further, in the present specification, the “nanocrystalline alloy ribbon” means an alloy ribbon containing nanocrystals. For example, the concept of “nanocrystalline alloy ribbon” includes not only an alloy ribbon consisting of only nanocrystals but also an alloy ribbon in which nanocrystals are dispersed in an amorphous phase.
Further, in the present specification, at least one selected from the group consisting of Fe, B, Si, Cu, and M (where M is Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W). The content (atomic %) of each element (representing the element of the seed) and the like means the content (atomic %) when the total of Fe, B, Si, Cu, and M is 100 atomic %.
Further, in the present specification, the angle formed by the two line segments (specifically, θ and α) is the smaller of the two defined angles (in the range of 0° to 90°). Angle).

The manufacturing method of the nanocrystalline alloy ribbon of the present embodiment (hereinafter, also referred to as “manufacturing method of the present embodiment”) is
A step of preparing an amorphous alloy ribbon having a composition represented by the following composition formula (A),
The amorphous alloy ribbon is continuously run under tension F, and a part of the region of the amorphous alloy ribbon continuously running under tension F is applied to a heat transfer medium maintained at a temperature of 450° C. or higher by the following formula ( By bringing them into contact with each other under the condition 1), the average temperature of the amorphous alloy ribbon in the temperature range from 350° C. to 450° C. is 10° C./sec or more until the ultimate temperature of 450° C. or higher is reached. Heating to obtain a nanocrystalline alloy ribbon,
including.
The manufacturing method of the present embodiment may include other steps than the above.

_{Fe 100-a-b-c} -d B a Si b Cu c M d ... formula (A)
[In the composition formula (A), a, b, c, and d are all atomic %, and 0<a, 0<b, 0<c, 0≦d, and 78≦100-a, respectively. -B-c-d is satisfied. M represents at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. ]

t _c >4/σ Equation (1)
[In the formula (1), t _c represents the time (seconds) from the time when any one point of the amorphous alloy ribbon comes into contact with the heat transfer medium to the time when the one arbitrary point separates from the heat transfer medium. σ represents the contact pressure (kPa) between the amorphous alloy ribbon and the heat transfer medium, which is defined by the formula (X) described later. ]

According to the study by the present inventors, when a nanocrystal alloy ribbon is manufactured by heat-treating an amorphous alloy ribbon by a conventional method, ripples (swells or wrinkles) may occur in the manufactured nanocrystal alloy ribbon. found.
Furthermore, the tendency for ripples to occur is particularly remarkable when an amorphous alloy ribbon having a composition represented by the composition formula (A) (that is, a composition having a Fe content of 78 atomic% or more) is heat-treated. It has been found.

In contrast to the conventional method, according to the manufacturing method of this embodiment, it is possible to manufacture a nanocrystalline alloy ribbon in which the generation of ripples is suppressed.
Therefore, when stacking the nanocrystalline alloy ribbons manufactured by the manufacturing method of the present embodiment (for example, when manufacturing a magnetic core), an improvement in space factor can be expected.
The height of the ripple (maximum height) of the nanocrystalline alloy ribbon is preferably less than 1.5 mm, more preferably 1.0 mm or less, and further preferably less than 0.1 mm (when no ripple occurs. Is included).

The reason why the nanocrystal alloy ribbon in which the generation of ripples is suppressed can be manufactured by the manufacturing method of the present embodiment is considered as follows. However, the present invention is not limited by the following reasons.

The cause of the ripple in the conventional method is estimated as follows.
When a nanocrystalline alloy ribbon is manufactured by heat-treating an amorphous alloy ribbon, in the process of heating for heat treatment, particularly in the process of raising the temperature range from 350° C. to 450° C., the movement of atoms causes the atoms to move from one atom to another. It is considered that clusters (mainly Cu clusters when the amorphous alloy ribbon contains Cu) are formed as aggregates. Then, it is considered that the nanocrystal alloy ribbon is manufactured by growing the nanocrystals with the above-mentioned clusters as nuclei in the temperature range of 450° C. or higher. Hereinafter, the growth of nanocrystals is also referred to as “nanocrystallization”.
In this case, under the condition that the size of the cluster becomes too large (that is, the condition that the moving time of atoms is relatively long), it is considered that the distribution density of clusters varies greatly depending on the position in the ribbon. As a result, the abundance density of the nanocrystals that grow with the clusters as the nuclei also varies greatly, that is, it is considered that the homogeneity of nanocrystallization decreases.
It is considered that the above-mentioned ripples occur due to variations in the existing density of nanocrystals (that is, deterioration of uniformity of nanocrystallization).

In view of the above points, in the manufacturing method of the present embodiment, the average heating rate in the temperature range from 350° C. to 450° C. (that is, the temperature range in which clusters are formed) (hereinafter, “average heating rate R _{350- The} temperature of the amorphous alloy ribbon is raised to the ultimate temperature of 450° C. or higher (that is, the amorphous alloy ribbon is heat-treated under these conditions) at a heating rate of 10° C./sec or more. It is considered that this reduces the time required for the atoms to move to form clusters, suppresses the size of clusters serving as the cores of the nanocrystals from becoming too large, and suppresses the variation in the density of clusters.
Further, in the manufacturing method of the present embodiment, due to the above-mentioned temperature rise (that is, heat treatment) of the amorphous alloy ribbon, a part of the region of the amorphous alloy ribbon that continuously runs in the state where tension F is applied is heated to a temperature of 450° C. or higher. The maintained heat transfer medium is brought into contact with the condition satisfying the expression (1). Specifically, the time t _c from when any one point of the continuously running amorphous alloy ribbon comes into contact with the heat transfer medium until when the one arbitrary point separates from the heat transfer medium (that is, the one point is heat transfer). The time for passing through this heat transfer medium while being in contact with the medium) is set to more than 4/σ. As a result, heat is sufficiently transferred from the heat transfer medium to the amorphous alloy ribbon, and nanocrystallization is sufficiently progressed from the amorphous material to obtain a nanocrystalline alloy ribbon. Moreover, as described above, when the average heating rate R _350-450 is 10° C./sec or more, variation in the density of the clusters serving as the cores of the nanocrystals is suppressed, so that the uniformity of nanocrystallization is improved. It is thought that.
According to the manufacturing method of the present embodiment, it is considered that the uniformity of nanocrystallization is improved and, as a result, the generation of ripples is suppressed for the above reason.

In short, in the manufacturing method of the present embodiment, t _c (seconds) exceeds 4/σ while shortening the time for cluster growth by setting the average heating rate R _350-450 to 10° _C./second or more. Thus, a nanocrystal alloy ribbon in which the generation of ripples is suppressed can be obtained by ensuring the time for nanocrystallization.

In the present specification, the average heating rate in the temperature range from 350° C. to 450° C. (average heating rate R _350-450 ) means the difference between 450° C. and 350° C. (that is, 100° C.) It means a value divided by the time (seconds) from when the temperature of any one point of the alloy ribbon reaches 350°C to when it reaches 450°C.
In the present embodiment, the average heating rate R _350-450 is 10° C./sec or more.
If the average heating rate R _350-450 is less than 10° C./sec, the time required for the atoms to move due to the growth of the clusters becomes long and the density of the clusters varies greatly, resulting in the nanocrystallization. The uniformity deteriorates, and ripples easily occur.
The average heating rate R _350-450 is preferably 100° C./second or more from the viewpoint of further suppressing the generation of ripples.
The upper limit of the average heating rate R _350-450 is not particularly limited, but examples thereof include 10000° C./sec, 900° C./sec, 800° C./sec, and the like.

Further, σ in the formula (1) is a contact pressure between the amorphous alloy ribbon and the heat transfer medium, which is defined by the following formula (X).

σ=((F×(sin θ+sin α))/a)×1000 Formula (X)
[In Formula (X), F represents a tension (N) applied to the amorphous alloy ribbon.
a represents the contact area (mm ² ) between the amorphous alloy ribbon and the heat transfer medium.
θ is an angle formed by the traveling direction of the amorphous alloy ribbon immediately before contacting the heat transfer medium and the traveling direction of the amorphous alloy ribbon when contacting the heat transfer medium, and is 3° or more and 60° or less. Represents the angle of.
α is an angle formed by the running direction of the amorphous alloy ribbon when in contact with the heat transfer medium and the running direction of the nanocrystalline alloy ribbon immediately after being separated from the heat transfer medium, and is more than 0° and 15°. The following angles are shown. ]

The formula (X) will be described in more detail below.
In the step of obtaining the nanocrystalline alloy ribbon according to the present embodiment, a part of the region of the amorphous alloy ribbon that continuously runs in a state where tension F is applied is brought into contact with the heat transfer medium. That is, in the present embodiment, the amorphous alloy ribbon to which the tension F is applied passes continuously through the heat transfer medium while maintaining contact with the heat transfer medium. The amorphous alloy ribbon becomes a nanocrystalline alloy ribbon by passing through the heat transfer medium.
Since the tension F is applied to the amorphous alloy ribbon, the traveling direction of the amorphous alloy ribbon immediately before contacting the heat transfer medium, the traveling direction of the amorphous alloy ribbon when contacting the heat transfer medium, and the heat transfer medium The traveling direction of the nanocrystalline alloy ribbon immediately after being separated from is linear.
However, the amorphous alloy ribbon may be meandering while passing through the transport roller and the like on the upstream side in the traveling direction from “immediately before coming into contact with the heat transfer medium”. Similarly, the nanocrystalline alloy ribbon obtained from the amorphous alloy ribbon may be meandering while passing through a transport roller or the like on the downstream side in the traveling direction from “immediately after leaving the heat transfer medium”.

In the formula (X), an angle θ formed between the traveling direction of the amorphous alloy ribbon immediately before contacting the heat transfer medium and the traveling direction of the amorphous alloy ribbon when contacting the heat transfer medium (see FIG. 1; , “Entry angle θ”) is 3° or more and 60° or less.
From the viewpoint of more effectively securing σ, the approach angle θ is preferably 5° to 60°, more preferably 10° to 60°, and particularly preferably 15° to 50°.

In the formula (X), an angle α formed between the traveling direction of the amorphous alloy ribbon when in contact with the heat transfer medium and the traveling direction of the nanocrystalline alloy ribbon immediately after being separated from the heat transfer medium (see FIG. 1; Hereinafter, also referred to as “exit angle α”) is more than 0° and 15° or less.
The exit angle α is preferably 0.05° or more and 10° or less, more preferably 0.05 or more and 5° or less.

Further, in the present embodiment, the contact between the partial area of the continuously running amorphous alloy ribbon and the heat transfer medium is performed in a state in which the tension F is applied to the amorphous alloy ribbon.
That is, the tension F in the formula (X) is more than 0N.
In the present embodiment, the tension F is more than 0 N, sin θ is more than 0 (specifically, θ is 3° or more and 60° or less), and sin α is more than 0 (more specifically, α is 0). >15° and less than 15°). Therefore, the contact pressure (σ) is also over 0 kPa. When the contact pressure (σ) is more than 0 kPa, the heat transfer from the heat transfer medium to the amorphous alloy ribbon is effectively performed.

The tension F is preferably 1.0 N to 40.0 N, more preferably 2.0 N to 35.0 N, and particularly preferably 3.0 N to 30.0 N.
When the tension F is 1.0 N or more, the generation of ripples can be further suppressed.
When the tension F is 40.0 N or less, breakage of the amorphous alloy ribbon or the nanocrystalline alloy ribbon can be further suppressed.

In the formula (X), the contact area a between the amorphous alloy ribbon and the heat transfer medium is preferably 500 mm ² or more, more preferably 1000 mm ² or more, from the viewpoint of more effectively promoting nanocrystallization. The upper limit of the contact area a is not particularly limited, but from the viewpoint of productivity, the upper limit of the contact area a is, for example, 10000 mm ² , and preferably 8000 mm ² or less.

Further, the length of the contact portion between the amorphous alloy ribbon and the heat transfer medium in the ribbon running direction depends on the width of the amorphous alloy ribbon, but is preferably 30 mm or more from the viewpoint of more effectively promoting nanocrystallization. 50 mm or more is more preferable.
The upper limit of the length of the contact portion in the ribbon traveling direction is not particularly limited, but from the viewpoint of productivity, the upper limit of the length of the contact portion in the ribbon traveling direction is, for example, 1000 mm, preferably 500 mm. ..

In the formulas (X) and (1), σ is preferably 0.1 kPa or more, and more preferably 0.4 kPa or more.
When σ is 0.1 kPa or more, it is easier to achieve the average heating rate R _350-450 (10°C/sec or more) described above. Further, when σ is 0.1 kPa or more, it is also advantageous in terms of reduction of coercive force (Hc).
The upper limit of σ is not particularly limited, but the upper limit is, for example, 20 kPa.

Further, in the formula (1), there is no particular limitation on the upper limit of the time (t _c ) from when any one point of the amorphous alloy ribbon comes into contact with the heat transfer medium until when the one arbitrary point leaves the heat transfer medium. However, t _c is preferably 300 seconds or less, more preferably 100 seconds or less, further preferably 50 seconds or less, and particularly preferably 10 seconds or less.
When t _c is 300 seconds or less, the productivity of the nanocrystalline alloy ribbon is further improved.
In addition, when t _c is 300 seconds or less (particularly, when the content of B described later is 10 atom% or more and 20 atom% or less), the soft magnetic characteristics (coercive force (Hc)) of the nanocrystalline alloy ribbon are obtained. , The saturation magnetic flux density (Bs), etc.) can be further reduced in the precipitation frequency of the Fe—B compound.
The lower limit of t _c is not particularly limited as long as the formula (1) is satisfied. From the viewpoint of production stability, t _c is preferably 0.5 seconds or more.

Further, as described above, in the present embodiment, the expression (1) (t _c >4/σ) is satisfied.
In the present embodiment, (4 / sigma) ratio of _{t c} for _{(t c / (4 / σ} )) is preferably at least 1.1, and more preferably 1.2 or more.
In the present embodiment, the difference between the _{t c (4 / σ) (} t c - (4 / σ)) is preferably 0.3 or more, and more preferably 0.5 or more.

Hereinafter, preferable aspects of the present embodiment will be described in more detail.

<Process of preparing amorphous alloy ribbon>
This step includes preparing an amorphous alloy ribbon having a composition represented by the following composition formula (A).

_{Fe 100-a-b-c} -d B a Si b Cu c M d ... formula (A)
[In the composition formula (A), a, b, c, and d are all atomic %, and 0<a, 0<b, 0<c, 0≦d, and 78≦100-a, respectively. -B-c-d is satisfied. M represents at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. ]

The amorphous alloy ribbon is a raw material for the nanocrystalline alloy ribbon manufactured in this embodiment.
The amorphous alloy ribbon is produced by satisfying “78≦100-abcd” (that is, the Fe content is 78 atomic% or more) in the composition formula (A). The saturation magnetic flux density (Bs) of the nanocrystalline alloy ribbon is improved.
Further, in the conventional manufacturing method, when the content of Fe in the amorphous alloy ribbon is 78 atomic% or more, ripples are likely to occur in the manufactured nanocrystalline alloy ribbon. On the other hand, in the manufacturing method of the present embodiment, the generation of ripples is suppressed as described above, even though the content of Fe in the amorphous alloy ribbon is 78 atomic% or more.
The “100-a-b-c-d” (that is, atomic% of Fe) in the composition formula (A) is preferably 80 or more.

In the above amorphous alloy ribbon, Cu has a function of efficiently promoting nanocrystallization with Cu clusters as nuclei by forming Cu clusters in the step of obtaining the nanocrystal alloy ribbon.
Since it has such a function, c (that is, atomic% of Cu) in the composition formula (A) is more than 0. From the viewpoint of more effectively exhibiting the function of Cu, c in the composition formula (A) is preferably 0.01 or more, and more preferably 0.5 or more. When c in the composition formula (A) is 0.5 or more, Cu clusters serving as nuclei of nanocrystal grains are likely to be formed in a state of being dispersed in the alloy structure, whereby nanocrystals formed by heat treatment. Coarsening of grains is suppressed, and variation in the particle size distribution of the nanocrystal grains is suppressed.
On the other hand, c in the composition formula (A) is preferably 1.2 or less. When c in the composition formula (A) is 1.2 or less, a larger Fe content can be secured, and thus Bs of the nanocrystalline alloy ribbon can be further improved. Further, when c is 1.2 or less, Cu cluster formation and nano-crystal grain precipitation can be further suppressed in the production stage (liquid quenching stage) of the amorphous alloy ribbon (before the above-mentioned temperature rise). Therefore, the nanocrystal alloy ribbon can be produced with higher reproducibility by the above-mentioned temperature rise.
Further, in the present embodiment, in the step of obtaining the nanocrystalline alloy ribbon, by satisfying the above average temperature rising rate and the above equation (1), even if c is 1.2 or less, nanocrystallization is achieved. It progresses sufficiently.
From the above viewpoints, c in the composition formula (A) is preferably more than 0 and 1.2 or less, more preferably 0.01 or more and 1.2 or less, and particularly preferably 0.5 or more and 1.2 or less.

In the above amorphous alloy ribbon, B has a function of stably maintaining the amorphous state before the step of raising the temperature of the amorphous alloy ribbon (step of obtaining the nanocrystalline alloy ribbon). By stably maintaining the amorphous state, it is possible to further improve the uniformity of nanocrystallization when manufacturing the nanocrystalline alloy ribbon, and it is possible to further improve Bs of the nanocrystalline alloy ribbon.
Since it has the above function, a in the composition formula (A) is more than 0 (that is, the content of B is more than 0 atomic%). From the viewpoint of more effectively exhibiting the function of B, a in the composition formula (A) is preferably 10.0 or more. When a in the composition formula (A) is 10.0 or more, the ability of forming an amorphous phase during casting is further improved, and thereby coarsening of nanocrystal grains formed by heat treatment is further suppressed.
On the other hand, a in the composition formula (A) is preferably 20.0 or less. When a in the composition formula (A) is 20.0 or less, a larger Fe content can be secured, and thus Bs of the nanocrystalline alloy ribbon can be further improved.
From the above viewpoint, a in the composition formula (A) is preferably more than 0 and 20.0 or less, more preferably 10.0 or more and 20.0 or less, still more preferably 12.0 or more and 18.0 or less, 12 It is more preferably 0.0 or more and 17.0 or less, particularly preferably 13.0 or more and 17.0 or less.

In the above amorphous alloy ribbon, Si has the functions of raising the crystallization temperature of the amorphous alloy ribbon and forming a strong surface oxide film.
Since it has the above function, b (that is, atomic% of Si) in the composition formula (A) is more than 0. When b in the composition formula (A) is more than 0, heat treatment at a higher temperature becomes possible (that is, it becomes possible to further increase the reached temperature of the above-mentioned temperature increase), so that the efficiency is improved. It becomes easy to form a dense and fine nanocrystalline structure, and by extension, Bs of the nanocrystalline alloy ribbon can be further improved. From the viewpoint of more effectively exhibiting the function of Si described above, b in the composition formula (A) is more preferably 0.1 or more.
On the other hand, b in the composition formula (A) is preferably 10.0 or less.
When b in the composition formula (A) is 10.0 or less, a larger content of Fe can be secured, and thus Bs of the nanocrystalline alloy ribbon can be further improved.
From the above viewpoint, b in the composition formula (A) is preferably more than 0 and 10.0 or less, more preferably 0.1 or more and 10.0 or less, still more preferably 1.0 or more and 8.0 or less, 2 It is more preferably 0.0 or more and 6.0 or less, and particularly preferably 3.5 or more and 5.0 or less.

In the composition formula (A), M is at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W.
In the present embodiment, M is an optional additional element, and the content of M may be 0 atomic% (that is, d in the composition formula (A) may be 0).
However, when the amorphous alloy ribbon contains M, the amorphous state is further stabilized before the step of raising the temperature of the amorphous alloy ribbon (step of obtaining the nanocrystalline alloy ribbon). As a result, it is possible to further improve the uniformity of nanocrystallization when manufacturing the nanocrystalline alloy ribbon, and it is possible to further improve Bs of the nanocrystalline alloy ribbon. From the viewpoint of exerting the function of M, d in the composition formula (A) is preferably more than 0. From the viewpoint of more effectively exhibiting the function of M, d in the composition formula (A) is preferably 0.1 or more, more preferably 0.2 or more.
On the other hand, d in the composition formula (A) is preferably 0.5 or less.
When d in the composition formula (A) is 0.5 or less, the decrease in soft magnetism is further suppressed.
From the above viewpoints, d in the composition formula (A) is preferably 0 or more and 0.5 or less, more preferably more than 0 and 0.5 or less, further preferably 0.1 or more and 0.5 or less, and 0.2 or more. 0.5 or less is particularly preferable.

From the viewpoint of further stabilizing the amorphous state, M preferably contains at least Mo or Nb among the above-mentioned elements, and more preferably contains at least Mo.

The amorphous alloy ribbon may contain impurities other than the above-mentioned Fe, B, Si, Cu, and M.
The impurities include at least one element selected from the group consisting of Ni, Mn, and Co. However, from the viewpoint of further suppressing the decrease in soft magnetism, the total content of these elements is preferably 0.4 mass% or less, more preferably 0.3 mass% or less, with respect to the total mass of the amorphous alloy ribbon. 0.2% by mass or less is particularly preferable.
Further, as the impurities, at least one element selected from the group consisting of Re, Zn, As, In, Sn, and rare earth elements can also be mentioned. However, from the viewpoint of further improving the saturation magnetic flux density (Bs), the total content of these elements is preferably 1.5% by mass or less and more preferably 1.0% by mass or less with respect to the total mass of the amorphous alloy ribbon. preferable.
Examples of the impurities include elements other than the above-mentioned elements, for example, O, S, P, Al, Ge, Ga, Be, Au, Ag, and the like.
The total content of impurities in the amorphous alloy ribbon is preferably 1.5% by mass or less, and more preferably 1.0% by mass or less, based on the total mass of the amorphous alloy ribbon.

The amorphous alloy ribbon can be produced by a known method such as a liquid quenching method in which a molten alloy is jetted onto a cooling roll that rotates axially.

The thickness of the amorphous alloy ribbon is not particularly limited, but is preferably 10 μm to 30 μm.
When the thickness is 10 μm or more, the mechanical strength of the amorphous alloy ribbon is secured, and breakage of the amorphous alloy ribbon is suppressed in the step of producing the amorphous alloy ribbon or the step of obtaining the nanocrystalline alloy ribbon. The thickness of the amorphous alloy ribbon is preferably 15 μm or more, more preferably 20 μm or more.
When the thickness is 30 μm or less, a stable amorphous state can be obtained in the amorphous alloy ribbon.

The width of the amorphous alloy ribbon is not particularly limited, but is preferably 5 mm to 100 mm.
When the width of the amorphous alloy ribbon is 5 mm or more, the suitability for manufacturing the amorphous alloy ribbon is excellent.
When the width of the amorphous alloy ribbon is 100 mm or less, the uniformity of nanocrystallization is further improved in the step of obtaining the nanocrystalline alloy ribbon.
The width of the amorphous alloy ribbon is preferably 70 mm or less.

Further, the preferable range of the thickness and width of the nanocrystalline alloy ribbon manufactured by the manufacturing method of the present embodiment is the same as the preferable range of the width and thickness of the amorphous alloy ribbon described above, respectively.

The step of preparing the amorphous alloy ribbon may include preparing a wound body of the amorphous alloy ribbon.
In this case, in the following step of obtaining the nanocrystalline alloy ribbon, the amorphous alloy ribbon unwound from the wound body of the amorphous alloy ribbon is continuously run in a state in which tension F is applied.

<Process of obtaining nanocrystalline alloy ribbon>
In this step, the amorphous alloy ribbon is continuously run in a state where tension F is applied, and a part of the region of the amorphous alloy ribbon which is continuously run in a state where tension F is applied becomes a heat transfer medium maintained at a temperature of 450° C. or higher. By bringing them into contact with each other under the conditions satisfying the above-described formula (1), the temperature of the amorphous alloy ribbon is 450° C. at an average heating rate of 10° C./sec or more in the temperature range from 350° C. to 450° C. Increasing the temperature to the ultimate temperature above to obtain a nanocrystalline alloy ribbon.
Some of the preferable embodiments of the step of obtaining the nanocrystalline alloy ribbon are as already described.

Examples of the heat transfer medium include a plate and a twin roll.
Examples of the material of the heat transfer medium include copper, copper alloys (bronze, brass, etc.), aluminum, iron, iron alloys (stainless steel, etc.), and the like, and copper, copper alloys, or aluminum are preferable.
The heat transfer medium may be subjected to plating treatment such as Ni plating and Ag plating.

The temperature of the heat transfer medium is 450° C. or higher as described above. This promotes nanocrystallization in the ribbon structure.
The temperature of the heat transfer medium is preferably 450°C to 550°C.
When the temperature of the heat transfer medium is 550° C. or lower (particularly, when the content of B described later is 10 atom% or more and 20 atom% or less), the soft magnetic characteristics (Hc, Bs, It is possible to further reduce the frequency of precipitation of the Fe-B compound, which can deteriorate (e.g.

In addition, in this step, the temperature of the amorphous alloy ribbon is raised to the ultimate temperature of 450° C. or higher. This promotes nanocrystallization in the ribbon structure.
The ultimate temperature is preferably 450°C to 550°C.
When the ultimate temperature is 550° C. or lower (particularly, when the content of B described later is 10 atom% or more and 20 atom% or less), the soft magnetic properties (Hc, Bs, etc.) of the nanocrystalline alloy ribbon are It is possible to further reduce the frequency of precipitation of the Fe-B compound that can deteriorate.
The ultimate temperature is preferably the same as the temperature of the heat transfer medium.

In this step, the temperature of the nanocrystalline alloy ribbon may be maintained on the heat transfer medium for a certain period of time after the temperature is raised.
Further, in this step, it is preferable to cool the obtained nanocrystalline alloy ribbon (preferably to room temperature).
In addition, this step may include winding the obtained nanocrystalline alloy ribbon (preferably the cooled nanocrystalline alloy ribbon) to obtain a wound body of the nanocrystalline alloy ribbon.

<One aspect of the manufacturing method of the present embodiment>
As a preferable mode of the manufacturing method of the present embodiment, an in-line annealing apparatus equipped with a heat transfer medium is used, and the amorphous alloy ribbon is brought into contact with the heat transfer medium for heat treatment to produce a nanocrystalline alloy ribbon ( Hereinafter, “Aspect X”) is included.

FIG. 1 is a partial side view conceptually showing a heat transfer medium of an in-line annealing apparatus and an amorphous alloy ribbon (nanocrystalline alloy ribbon after contact with the heat transfer medium) in contact with the heat transfer medium in the embodiment X. It is a figure.
As shown in FIG. 1, in the mode X, the amorphous alloy ribbon 10A continuously runs in the direction of the block arrow by contacting the amorphous alloy ribbon 10A with the heat transfer medium 20 maintained at a temperature of 450° C. or higher. Heat treatment. Hereinafter, the details of this heat treatment will be described step by step for the sake of convenience, but the following heat treatment is performed continuously.
First, the amorphous alloy ribbon 10A to which the tension F is applied by a tensioner (not shown) is caused to enter the heat transfer medium 20 maintained at a temperature of 450° C. or higher at the approach angle θ. As a result, the amorphous alloy ribbon 10A is brought into contact with the heat transfer medium 20.
Next, the amorphous alloy ribbon 10A is heat-treated by the heat transfer medium 20 to obtain the nanocrystal alloy ribbon 10B. Specifically, the amorphous alloy ribbon 10A is brought into contact with the heat transfer medium 20 under the condition that the above formula (1) (t _c >4/σ) is satisfied, so that the average heating rate in the temperature range from 350° C. to 450° C. The nanocrystalline alloy ribbon 10B is obtained by raising the temperature to 450° C. or higher under the condition that R _350-450 is 10° C./sec or higher.
The preferable ranges of the average heating rate R _350-450 and t _c and σ in the above formula (1) are as described above.

After the heat treatment, the nanocrystalline alloy ribbon 10B is withdrawn from the heat transfer medium 20 at an exit angle α, and then cooled to room temperature (air cooling). Then, the nanocrystal alloy ribbon 10B is wound by a winding roll (not shown).

Examples of the present invention will be shown below, but the present invention is not limited to the following examples.

[Example 1]
<Preparation of ribbon containing nanocrystals>
By a liquid quenching method in which a molten alloy is jetted onto an axially rotating cooling roll, a composition represented by Fe _80.8 B _14.0 Si _4.0 Cu _1.0 Mo _0.2 , width 25.4 mm, thickness A 23 μm thick amorphous alloy ribbon was manufactured.
As a result of X-ray diffraction and transmission electron microscope (TEM) observation, no precipitation of nanocrystals was confirmed in the amorphous phase of the amorphous alloy ribbon.

Next, according to Aspect X described above, a nanocrystalline alloy ribbon was produced by bringing the amorphous alloy ribbon into contact with the heat transfer medium and performing heat treatment using an in-line annealing apparatus equipped with the heat transfer medium. The obtained nanocrystalline alloy ribbon was withdrawn from the heat transfer medium and then cooled (air-cooled) to room temperature.
The manufacturing conditions in Example 1 are as follows.

-Manufacturing conditions in Example 1-
Heat transfer medium: Bronze plate Temperature of heat transfer medium: 480°C
Tension applied to amorphous alloy ribbon F: 3.0N
Contact area a between the amorphous alloy ribbon and the heat transfer medium a: 1880 mm ²
Approach angle θ: 5°
Contact pressure σ between the amorphous alloy ribbon and the heat transfer medium: 0.28 kPa (calculated value based on the above formula (X)).
Exit angle α: 5°
The average heating rate _{R 350-450:} 20 ℃ / sec reaching temperature _T a: 480 ° C.

When the cross section of the nanocrystal alloy ribbon after cooling was observed by TEM, the nanocrystal alloy ribbon after cooling contained nanocrystal grains having a crystal grain size of 1 nm or more and 40 nm or less. In addition, the content of the nanocrystalline grain phase in the nanocrystalline alloy ribbon after cooling was 30% by volume or more.
In the present example, the area ratio (%) of the nano-crystal grains having a crystal grain size of 1 nm or more and 40 nm or less in the entire TEM image of the visual field area of 1 μm×1 μm was obtained, and the area ratio (%) was calculated as The content (volume %) of the nano-crystal grain phase in the alloy ribbon was used.

In addition, it was confirmed by ICP emission spectroscopic analysis that the nanocrystalline alloy ribbon after cooling had the same composition as the raw material amorphous alloy ribbon.

<Measurement of nanocrystal-containing ribbon>
The maximum value of the ripple height (mm) of the cooled nanocrystalline alloy ribbon was measured using a caliper. The results are shown in Table 1.

[Examples 2-9, Comparative Examples 1-5]
The same operation as in Example 1 was performed except that the production conditions were changed as shown in Table 1.
The results are shown in Table 1.
Here, the contact pressure σ was changed by changing the combination of the tension F, the contact area a, and the approach angle θ, and the contact time t _c was changed by changing the advancing speed of the amorphous alloy ribbon.
The contact area a was changed by changing the length in the ribbon traveling direction of the contact portion of the heat transfer medium with the amorphous alloy ribbon.

In any of Examples 2 to 9, the nanocrystal alloy ribbon after cooling contains nanocrystal grains having a crystal grain size of 1 nm or more and 40 nm or less, and the content of the nanocrystal grain phase in the nanocrystal alloy ribbon is It was 30% by volume or more.

As shown in Table 1, ripples were suppressed in the nanocrystalline alloy ribbons of Examples 1 to 9 manufactured under the conditions satisfying t _c >4/σ [that is, formula (1)].
On the other hand, remarkable ripples were generated in the nanocrystalline alloy ribbons of Comparative Examples 1 to 5 which did not satisfy t _c >4/σ [that is, the formula (1)].

The disclosure of US provisional patent application 62/300,938, filed February 29, 2016, is hereby incorporated by reference in its entirety.
All publications, patent applications, and technical standards mentioned herein are to the same extent as if each individual publication, patent application, and technical standard were specifically and individually noted to be incorporated by reference, Incorporated herein by reference.

Claims (6)

A step of preparing an amorphous alloy ribbon having a composition represented by the following composition formula (A),
The amorphous alloy ribbon is continuously run under tension F, and a partial region of the amorphous alloy ribbon continuously running under tension F is applied to a heat transfer medium maintained at a temperature of 450° C. or higher. By bringing them into contact with each other under the condition satisfying the following formula (1), the temperature of the amorphous alloy ribbon is 450° C. or more at a heating rate such that the average heating rate in the temperature range from 350° C. to 450° C. is 10° C./sec or more. To obtain a nanocrystalline alloy ribbon by raising the temperature reached to
A method for manufacturing a nanocrystalline alloy ribbon containing:
_{Fe 100-a-b-c} -d B a Si b Cu c M d ... formula (A)
[In the composition formula (A), a, b, c, and d are all atomic %, and 0<a, 0<b, 0<c, 0≦d, and 78≦100-a, respectively. -B-c-d is satisfied. M represents at least one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, and W. ]
t _c >4/σ Equation (1)
[In Formula (1), t _c represents the time (seconds) from the time when any one point of the amorphous alloy ribbon comes into contact with the heat transfer medium to the time when the one arbitrary point separates from the heat transfer medium. σ represents a contact pressure (kPa) between the amorphous alloy ribbon and the heat transfer medium, which is defined by the following formula (X). ]
σ=((F×(sin θ+sin α))/a)×1000 Formula (X)
[In Formula (X), F represents a tension (N) applied to the amorphous alloy ribbon.
a represents a contact area (mm ² ) between the amorphous alloy ribbon and the heat transfer medium.
θ is an angle formed by the running direction of the amorphous alloy ribbon immediately before contact with the heat transfer medium and the running direction of the amorphous alloy ribbon when in contact with the heat transfer medium, and is 3°. It represents an angle of not less than 60°.
α is an angle formed by the traveling direction of the amorphous alloy ribbon when in contact with the heat transfer medium and the traveling direction of the nanocrystalline alloy ribbon immediately after being separated from the heat transfer medium, and 0 It represents an angle of more than 15° and less than 15°. ] The method for producing a nanocrystalline alloy ribbon according to claim 1, wherein the σ is 0.1 kPa or more. The method for producing a nanocrystalline alloy ribbon according to claim 1, wherein the σ is 0.4 kPa or more. The method for producing a nanocrystalline alloy ribbon according to any one of claims 1 to 3, wherein the t _c is 300 seconds or less. In said composition formula (A), said c is 0.5 or more and 1.2 or less, The manufacturing method of the nanocrystal alloy ribbon of any one of Claims 1-4. The nanocrystal according to any one of claims 1 to 5, wherein in the composition formula (A), the a is 10.0 or more and 20.0 or less and the b is more than 0 and 10.0 or less. Method for manufacturing alloy ribbon.