JP2002030378A - Method for producing iron-based permanent magnet alloy by control of crystallization heat generating temperature - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decide the combination and ratios of rare earth elements to be added to an iron-based alloy magnet by a systematic means and to impart excellent magnet characteristics thereto. SOLUTION: In this method for producing a fine crystal type iron-based alloy magnet having two or more metastable phases including hard magnetic phase, a stage in which an iron-based alloy containing a rare earth element R (R is Pr or Nd), a rare earth element R' having an atomic number A larger than that of the rare earth element R and a rare earth element R" having an atomic number A smaller than that of the rare earth element R is prepared, a stage in which the molten metal of the iron- based alloy is rapidly cooled, by which a rapidly cooled alloy in which the volume ratio of an amorphous phase occupies >=90% of the whole is prepared and a heat treating stage in which the rapidly cooled alloy is heated to progress the growth of the crystals in the iron-based alloy are included. Then, by regulating the compositional ratios of R, R' and R", the crystallization heat generating temperature of one crystal phase is controlled to 585 to 615 deg.C, and further, the crystallization heat generating temperature of the other crystal phase is controlled to 610 to 640 deg.C, so that a fine and uniform crystal structure is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a microcrystalline iron-based alloy magnet suitably used for various motors and actuators.

[0002]

2. Description of the Related Art Research and development of microcrystalline alloy magnets having two or more metastable phases including at least a hard magnetic phase have been conducted. For example, in the case of a Fe ₃ B / Nd ₂ Fe ₁₄ B-based fine crystal type magnet, Fe ₃ B microcrystals as a soft magnetic phase and Nd ₂ Fe ₁₄ B microcrystals as a hard magnetic phase are uniformly distributed, and exchange interaction Thus, the two are magnetically coupled. These microcrystals have a size on the order of nanometers (nm), and constitute a composite structure (nanocomposite structure) of both microcrystalline phases, and thus may be referred to as a “nanocomposite magnet”.

[0003] Such a microcrystalline iron-based alloy magnet is
Even if a soft magnetic phase is included, excellent magnetic properties can be exhibited by magnetic coupling (exchange interaction) with the hard magnetic phase. In addition, as a result of the presence of the soft magnetic phase containing no rare earth element such as Nd, the content of the rare earth element can be kept low as a whole. This reduces the cost of manufacturing magnets,
This is also advantageous in providing a stable supply of magnets.

[0004] The microcrystalline iron-based alloy magnet is manufactured using a method in which a molten raw material alloy is rapidly cooled to be amorphous, and then microcrystals are precipitated and grown (crystallized) by heat treatment.

[0005] A rapidly solidified alloy in an amorphous state is generally produced by a super-quenching method such as a single roll method. In the quenching method, for example, a molten raw material alloy flows down on the outer peripheral surface of a rotating cooling roll, and the raw material alloy is rapidly cooled and solidified by bringing the molten raw material alloy into contact with the cooling roll for a short time. In this method, the cooling speed is controlled by adjusting the peripheral speed of the cooling roll.

The alloy solidified by quenching and separated from the chill roll becomes a ribbon (thin strip) that is thin and long in the peripheral speed direction. Such a strip of the rapidly solidified alloy is crushed by a breaker to be flaked, and then crushed to a finer size by a crusher and powdered.

After that, heat treatment for crystallization is performed. By this heat treatment, iron-based borides such as Fe ₃ B and N
A microcrystalline phase of d ₂ Fe ₁₄ B is generated, giving magnet properties.

[0008]

Heretofore, attempts have been made to combine various additive elements and optimize their composition ratio in order to improve the performance of the microcrystalline iron-based alloy magnet. However, no systematic method for determining the combination or composition ratio of the added elements has been known, and these determinations have been made by trial and error. Therefore, in order to develop a high-performance iron-based alloy magnet having a novel composition, a great deal of time and labor was required.

The present invention has been made in view of the above points, and a main object of the present invention is to determine the combination and composition ratio of additive elements by a systematic method, and thereby to provide an iron having excellent magnet properties. An object of the present invention is to provide a method for manufacturing a base permanent magnet alloy.

[0010]

SUMMARY OF THE INVENTION An iron-based permanent magnet according to the present invention.
The method for producing a stone alloy is as follows._xT_(100-xylm)Q _y
M1_lM2_m(At%) (R = La, Ce, P
r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, H
Select from the group consisting of o, Er, Tm, Yb, and Lu
From two or more elements, T = Fe, Co, and Ni
At least one element selected from the group consisting of Q = B and
At least one element selected from the group consisting of
Element, M1 = Cu, Ga, Si, Al, and Pb
At least one element selected from the group
selected from the group consisting of b, Mo, Ti, and Zr
At least one element), a symbol x for limiting the composition range,
y, l, m are respectively 1 ≦ x ≦ 6, 15 ≦ y ≦ 2
5, 0.01 ≦ l ≦ 0.4, and 0.05 ≦ m ≦ 5
Two or more crystals satisfying the relationship and containing at least a hard magnetic phase
This is a method for producing iron-based permanent magnet alloys with mixed phases.
And the composition and composition ratio of the elements R, M1, and M2
By adjusting the crystallization exotherm of one crystal phase
While controlling the temperature between 585 ° C and 615 ° C,
Control crystallization exothermic temperature of crystal phase to 610 ° C-640 ° C
It is characterized by the following.

[0011] A method for producing an iron-based permanent magnet alloy according to the present invention.
Means that the composition formula is (Nd_{x-x '}R '_{x '}) T _(100-xylm)Q_yM
1_lM2_m(R '= Pm, Sm, E)
u, Gd, Tb, Dy, Ho, Er, Tm, Yb, and
At least one element selected from the group consisting of
Element, T = selected from the group consisting of Fe, Co, and Ni
Group consisting of at least one selected element, Q = B and C
At least one element selected from: M1 = Cu, G
a, selected from the group consisting of Si, Al, and Pb
At least one element, M2 = Nb, Mo, Ti, and
At least one element selected from the group consisting of
Element), symbols x, x ', y, l, m for limiting the composition range
Is 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25,
0.01 ≦ l ≦ 0.4 and 0.05 ≦ m ≦ 5
And at least two crystal phases including the hard magnetic phase
A method for producing a mixed iron-based permanent magnet alloy, comprising:
at least a part of d is a rare earth having an atomic number greater than Nd
Each crystal phase by substituting with a similar element R '
Increase the exothermic temperature of the crystallization of
When the exothermic temperature of crystallization of the phase is controlled between 585 ° C and 615 ° C,
In both cases, the exothermic crystallization temperature of the other crystal phases is 610 ° C. to 64 ° C.
It is characterized in that it is controlled at 0 ° C.

A method for producing an iron-based permanent magnet alloy according to the present invention.
Means that the composition formula is (Nd_{x-x '}R "_{x '}) T _(100-xylm)Q_yM
1_lM2_m(At%) (R ″ = La, Ce, and
At least one element selected from the group consisting of
Element, T = selected from the group consisting of Fe, Co, and Ni
Group consisting of at least one selected element, Q = B and C
At least one element selected from: M1 = Cu, G
a, selected from the group consisting of Si, Al, and Pb
At least one element, M2 = Nb, Mo, Ti, and
At least one element selected from the group consisting of
Element), symbols x, x ', y, l, m for limiting the composition range
Is 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25,
0.01 ≦ l ≦ 0.4 and 0.05 ≦ m ≦ 5
And at least two crystal phases including the hard magnetic phase
A method for producing a mixed iron-based permanent magnet alloy, comprising:
at least a part of d is a rare earth having an atomic number smaller than Nd
Each crystal phase by substituting with a similar element R ″
Lowers the exothermic temperature of the crystallization of one crystal
When the exothermic temperature of crystallization of the phase is controlled between 585 ° C and 615 ° C,
In both cases, the exothermic crystallization temperature of the other crystal phases is 610 ° C. to 64 ° C.
It is characterized in that it is controlled at 0 ° C.

In a preferred embodiment, it contains an iron-based boride phase and R ₂ T _{1 4} B type compound phase as the two or more crystalline phases, T ₁ a crystallization exotherm temperature of the iron-based boride phase, The exothermic crystallization temperature of the R ₂ T ₁₄ B type compound phase is T ₂ , the atomic number of the rare earth element substituted with Nd is A, and x ′ is 0 at%.
The crystallization exothermic temperature of the iron-based boride phase at T _{1 (x ′
= 0)} , and T ₁ = α ₁ (A−60) + T ₁ , where T _{2 ( x ′ = 0)} is the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase when x ′ is _{0 at} %. _{(x '= 0)} (0 <α ₁ ≦ 1
0), T ₂ = α ₂ (A−60) + T _{2 (x ′ = 0)} (0 <α ₂ ≦ 2
0) is satisfied.

In a preferred embodiment, it contains an iron-based boride phase and R ₂ T _{1 4} B type compound phase as the two or more crystalline phases, T ₁ a crystallization exotherm temperature of the iron-based boride phase, The crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase is set to the i-th (1 <i ≦ 1) of N rare earth elements substituted with T ₂ and Nd.
The atomic number of the element (N) is A _i , the heat of crystallization of the iron-based boride phase when x ′ is 0 at% is T _{1 (x ′ = 0)} , x ′
When the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase at 0 at% is T _{2 (x ′ = 0)} , T ₁ = Σα _i1 (A _i −60) + T _{1 (x ′ = 0) )} (0 <α
_i1 ≦ 10) T ₂ = Σα _i2 (A _i −60) + T _{2 (x ′ = 0)} (0 <α
_i2 ≦ 20).

[0015] A method for producing an iron-based permanent magnet alloy according to the present invention.
Means that the composition formula is (Pr_{x-x '}R '_{x '}) T _(100-xylm)Q_yM
1_lM2_m(At%) (R ′ = Nd, Sm, E
u, Gd, Tb, Dy, Ho, Er, Tm, Yb, and
At least one element selected from the group consisting of
Element, T = selected from the group consisting of Fe, Co, and Ni
Group consisting of at least one selected element, Q = B and C
At least one element selected from: M1 = Cu, G
a, selected from the group consisting of Si, Al, and Pb
At least one element, M2 = Nb, Mo, Ti, and
At least one element selected from the group consisting of
Element), symbols x, x ', y, l, m for limiting the composition range
Is 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25,
0.01 ≦ l ≦ 0.4 and 0.05 ≦ m ≦ 5
And at least two crystal phases including the hard magnetic phase
A method for producing a mixed iron-based permanent magnet alloy, comprising:
at least a part of r is a rare earth having an atomic number greater than Pr
Each of the crystalline phases by substituting with a similar element R '
Increase the exothermic temperature of the crystallization of
When the exothermic temperature of crystallization of the phase is controlled between 585 ° C and 615 ° C,
In both cases, the exothermic crystallization temperature of the other crystal phases is 610 ° C. to 64 ° C.
Control at 0 ° C.

A method for producing an iron-based permanent magnet alloy according to the present invention
Means that the composition formula is (Pr_{x-x '}R "_{x '}) T _(100-xylm)Q_yM
1_lM2_m(R% = La and Ce)
At least one element selected from the group consisting of:
A small number selected from the group consisting of Fe, Co, and Ni.
At least one element, selected from the group consisting of Q = B and C
At least one element, M1 = Cu, Ga, S
at least one selected from the group consisting of i, Al, and Pb
And one element, M2 = Nb, Mo, Ti, and Zr
At least one element selected from the group consisting of
Symbols x, x ', y, l, and m that limit the composition range are 1 ≦ x
≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25, 0.01 ≦
satisfying the relationship of l ≦ 0.4 and 0.05 ≦ m ≦ 5,
Iron containing at least two crystalline phases including at least a hard magnetic phase
A method for producing a base permanent magnet alloy, wherein Pr is reduced.
A part of which is a rare earth element R having a smaller atomic number than Pr
Crystallization of each crystal phase
Lowering the thermal temperature, thereby crystallizing one crystalline phase
The exothermic temperature is controlled between 585 ° C and 615 ° C.
Exothermic temperature of crystallization of crystalline phase of 610 to 640 ° C
It is characterized by doing.

In a preferred embodiment, it contains an iron-based boride phase and R ₂ T _{1 4} B type compound phase as the two or more crystalline phases, T ₁ a crystallization exotherm temperature of the iron-based boride phase, The exothermic crystallization temperature of the R ₂ T ₁₄ B type compound phase is T ₂ , the atomic number of the rare earth element substituted with Pr is A, and x ′ is 0 at%.
The crystallization exothermic temperature of the iron-based boride phase at T _{1 (x ′
= 0)} , and T ₁ = α ₁ (A−59) + T ₁ , where T _{2 ( x ′ = 0)} is the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase when x ′ is _{0 at} %. _{(x '= 0)} (0 <α ₁ ≦ 1
0) T ₂ = α ₂ (A−59) + T _{2 (x ′ = 0)} (0 <α ₂ ≦ 2
0) is satisfied.

In a preferred embodiment, it contains an iron-based boride phase and R ₂ T _{1 4} B type compound phase as the two or more crystalline phases, T ₁ a crystallization exotherm temperature of the iron-based boride phase, The crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase is the i-th (1 <i ≦ 1) of the N rare earth elements substituted with T ₂ and Pr.
The atomic number of the element (N) is A _i , the heat of crystallization of the iron-based boride phase when x ′ is 0 at% is T _{1 (x ′ = 0)} , x ′
Is 0 at%, the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase is T _{2 (x ′ = 0),} and T ₁ = Σα _i1 (A _i −59) + T _{1 (x ′ = 0) )} (0 <α
_i1 ≦ 10) T ₂ = Σα _i2 (A _i −59) + T _{2 (x ′ = 0)} (0 <α
_i2 ≦ 20).

In the method for producing an iron-based permanent magnet alloy according to the present invention, a hard magnetic property is exhibited by subjecting an iron-based rapidly solidified alloy having an amorphous structure of at least 90% by volume to a heat treatment for crystallization. A method for producing an iron-based permanent magnet alloy that forms a possible alloy structure, comprising: changing the combination of the rare earth element R, the additional elements M1 and M2, and the content of the alloy composition to form the crystal of the rapidly solidified alloy. The heat generation temperature is controlled.

The method for producing an iron-based permanent magnet alloy according to the present invention is a method for producing a microcrystalline iron-based alloy magnet having two or more metastable phases including a hard magnetic phase, wherein the rare-earth element R
A step of preparing an iron-based alloy containing (R is Pr or Nd), a rare earth element R ′ having a larger atomic number than the rare earth element R, and a rare earth element R ″ having a smaller atomic number than the rare earth element R; Quenching the melt of the iron-based alloy, thereby producing a quenched alloy in which the amorphous phase accounts for 90% or more of the whole by volume; and heating the quenched alloy to grow crystals in the iron-based alloy. And adjusting the composition ratio of the rare earth element R, the rare earth element R ′, and the rare earth element R ″, so that the average crystal grain size after the heat treatment step is 1 nm or more.
A fine structure of 0 nm or less is formed.

In a preferred embodiment, the composition ratio of the rare earth element R, the rare earth element R ′, and the rare earth element R ″ is such that the phase of the metastable phase having the lowest crystallization exothermic temperature is the maximum crystallization exotherm temperature. The phase is adjusted so that the difference from the crystallization heating temperature of the phase having a high heating temperature is 5 ° C. or more and 25 ° C. or less.

A bonded magnet according to the present invention is characterized in that it is formed using an iron-based permanent magnet alloy powder produced by any one of the above-mentioned production methods.

A rotating machine according to the present invention is provided with the above-mentioned bonded magnet.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS High-performance RTB by the quenching method
As an effective means for producing a system-based magnet, the exothermic temperature of crystallization of one crystal phase (for example, boride phase) to be formed in a quenched alloy is set to, for example, 585 ° C. to 615 ° C., and another crystal phase (for example, R there are ₂ T ₁₄ B compound phase) method for controlling the crystallization exotherm temperature, for example to 610 ° C. to 640 ° C. for. By adjusting the crystallization heating temperature of each constituent phase to such a range, a uniform and fine structure can be formed by the recrystallization heat treatment, and an iron-based alloy magnet having excellent magnetic properties can be obtained.

The present inventor has found that when an RTB-based iron-based permanent magnet alloy is manufactured by a quenching method, at least a part of the rare earth element R is a rare earth element R ′ having a larger atomic number than the rare earth element R or The present inventors have found that the crystallization heat generation temperature of the constituent phase can be controlled with high accuracy by substituting with a rare earth element R ″ having a smaller atomic number than the rare earth element R, and have arrived at the present invention.

Specifically, the following findings were obtained through various experiments by the present inventors.

(1) 0.1 at% or more of the rare earth element R is a rare earth element R 'having an atomic number larger than that of the rare earth element R
Can increase the heat of crystallization of the soft magnetic phase and the hard magnetic phase by 0.1 ° C. or more.

(2) 0.1 at% or more of the rare-earth element R is a rare-earth element R having a smaller atomic number than the rare-earth element R.
Can reduce the crystallization exothermic temperature of the soft magnetic phase and the hard magnetic phase by 0.1 ° C. or more.

(3) It is possible to optimize the crystallization exothermic temperature of the soft magnetic phase and the hard magnetic phase by complexly substituting at least a part of the rare earth element R with the rare earth element R ′ and the rare earth element R ″. It will be easy to do.

FIG. 1 is a graph showing R containing Rd as a rare earth element.
The atomic numbers A and Fe of the added rare earth element when a rare earth element R 'having an atomic number A larger than the atomic number of Nd or a rare earth element R "having an atomic number smaller than that of Nd are added to the -TB series quenched alloy. ₃ shows the relationship with the crystallization exothermic temperature of the B phase (assuming a compound in which a part of Fe or B is substituted by another element), and the atomic number A of Nd is 6
0. FIG. 1 shows that the added amount x ′ of the rare earth element is 0.1
at%, 1.0 at%, 2.0 at%, and 4.5a
The exothermic crystallization temperature at t% is shown. Also, F
A region that is preferable as the crystallization heating temperature of the e ₃ B phase is surrounded by a broken line in FIG.

On the other hand, FIG. 2 shows that, under the same conditions as in FIG. 1, the atomic number A of the added rare earth element and the R ₂ Fe ₁₄ B phase (Fe or B is partially replaced by another element). ) Of the compound (including the compound).
Note that a region preferable as the crystallization heat generation temperature of the R ₂ Fe ₁₄ B phase is surrounded by a broken line in the graph of FIG.

As can be seen from FIGS. 1 and 2 above,
By substituting Nd with a rare earth element having an atomic number A larger than that of Nd, the heat of crystallization can be increased for any of Fe ₃ B and R ₂ Fe ₁₄ B phases. Similarly, by substituting Nd with a rare earth element having an atomic number A smaller than that of Nd, Fe ₃ B and R ₂ Fe
_The crystallization exothermic temperature can be lowered for any phase of _14B .

It should be noted that there is a linear relationship between the atomic number of the rare earth element to be added and the increase in the crystallization heating temperature as shown in the figure. Therefore, when a plurality of types of rare earth elements are added in combination, it is possible to calculate the atomic number of the selected rare earth element and the amount of addition (substitution amount) to obtain a desired crystallization heating temperature.

For example, consider a case where an iron-based alloy magnet containing Nd as a rare earth element and having a fine crystal structure of an iron-based boride phase and an R ₂ Fe ₁₄ B type compound phase is manufactured. In this case, the crystallization exothermic temperature of the iron-based boride phase is T ₁ , R ₂
The crystallization exothermic temperature of the Fe ₁₄ B-type compound phase is represented by T ₂ , and the atomic number of the rare earth element substituted with Nd is represented by A. Also, Nd
When no other rare earth element is added (addition amount x '= 0a
(in the case of t%), the crystallization exotherm temperature of the iron-based boride phase is T _{1 (x ′ = 0)} , and the crystallization exotherm temperature of the R ₂ Fe ₁₄ B type compound phase is T _{2 (x ′ = 0)} . . At this time, the following two equations are substantially established.

T ₁ = α ₁ (A−60) + T _{1 (x ′ = 0)}
(0 <α ₁ ≦ 10) T ₂ = α ₂ (A−60) + T _{2 (x ′ = 0)} (0 <α ₂ ≦ 2
0) Here, α1 and α2 depend on the addition amount x ′,
This coefficient does not depend on the atomic number A. α1 and α2
Is determined by experiment.

When a part of Nd is replaced with N kinds of different rare earth elements, among the rare earth elements to be replaced, the atomic number of the i-th (1 <i ≦ N) rare earth element is represented by A _i . The following two equations are almost satisfied.

T ₁ = Σα _i1 (A _i −60) + T _{1 (x ′ = 0)}
(0 <α _i1 ≦ 10) T ₂ = Σα _i2 (A _i −60) + T _{2 (x ′ = 0)} (0 <α
_i2 ≦ 20) Here, α _i1 and α _i2 are coefficients when the i-th rare earth element satisfying 1 <i ≦ N is independently added and replaced with Nd. These coefficients depend on the amount of addition, as described above.

By using the above equation, the optimum composition which shows the desired crystallization exothermic temperature of each constituent phase of the magnet can be determined in a time greatly reduced in comparison with the conventional trial and error method. It becomes possible to do.

Hereinafter, a method for producing an iron-based permanent magnet alloy according to the present invention will be described.

In the present invention, first, the composition formula is R _x T
_{(100-x'-ylm) Q} y M1 l M2 m (at%) to produce a melt of iron-base alloy represented by. Here, R is La, C
e, Pr, Nd, Pm, Sm, Eu, Gd, Tb, D
at least one element selected from the group consisting of y, Ho, Er, Tm, Yb, and Lu;
e, at least one element selected from the group consisting of Co, and Ni. Q is at least one element selected from the group consisting of B (boron) and (carbon). M1 is at least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb, and M2 is at least one element selected from the group consisting of Nb, Mo, Ti, and Zr. Element.

The symbols x, y, l, and m that limit the composition range are 1 ≦ x ≦ 6, 15 ≦ y ≦ 25, 0.
The relationship of 01 ≦ l ≦ 0.4 and 0.05 ≦ m ≦ 5 is satisfied.

Here, based on the linear relationship shown in FIGS. 1 and 2, a combination of rare earth elements is selected,
The exothermic crystallization temperature of the iron-based boride phase is controlled at 585 ° C to 615 ° C, and the exothermic crystallization temperature of the R ₂ Fe ₁₄ B phase is controlled at 610 ° C to 640 ° C.

Next, by rapidly cooling the molten alloy, a rapidly solidified alloy containing 90% or more by volume of an amorphous phase is produced. Thereafter, a heat treatment for crystallization is performed on the rapidly solidified alloy, and the iron-based boride phase and R ₂
Generate and grow the Fe ₁₄ B phase. Average particle size is 1 to 50
A nanostructure of nm is formed. Thus, an iron-based permanent magnet alloy in which two or more kinds of fine crystal phases are mixed is produced.

According to the present invention, the crystallization exothermic temperature of each constituent phase can be optimized by adjusting the combination and composition ratio of the rare earth elements, and as a result, the crystal structure after the heat treatment can be uniformly refined. And the magnet characteristics can be improved.

Next, the reasons for limiting the composition range in the present invention will be described.

[Reason for Limiting Composition] The rare earth element R is an element necessary for forming a hard magnetic phase (for example, R ₂ Fe ₁₄ B). The rare earth element R in the present invention contains at least 90 atomic% of one or both elements of Pr and Nd, and the remainder contains 0% or more of other lanthanum series element or one or more elements of Y.
It is preferable to contain less than 0%. One of the elements Pr and Nd is R ₂ Fe having uniaxial crystal magnetic anisotropy.
_This is because it contributes to the generation of a compound phase having a _14B- type crystal structure. If the composition ratio of the rare earth element is less than 1 atomic%, the effect of generating a coercive force is too small, which is not preferable. on the other hand,
If the composition ratio of the rare earth element R exceeds 6 atomic%, Fe ₃
Since the B phase and the Nd ₂ Fe ₁₄ B phase are not generated and the Nd ₂ Fe ₂₃ B ₃ phase, which is a soft magnetic phase, becomes the main phase, the coercive force is significantly reduced. From the above, the composition ratio x of the rare earth element R is preferably 1 ≦ x ≦ 6. Further, a more preferable range of the composition ratio x of the rare earth element R is 1 ≦ x ≦ 5.5.

The rare earth elements R ′ and / or R ″ are essential elements for controlling the crystallization exothermic temperature of the quenched alloy, and the crystallization exothermic temperature increases linearly as the rare earth element atomic number increases. As the content of R ′ with respect to the rare earth element R increases, the slope of the linear function increases.Therefore, the composition ratio of the rare earth element R ′ and / or R ″ in the total content of the rare earth element increases. If it exceeds 4.5 atomic%, the gradient of the linear function (the amount of change in the crystallization heating temperature) becomes too large, so that good magnetic properties cannot be obtained. Rare earth elements R 'and / or
Alternatively, the amount of R ″ is preferably 4.5 atomic% or less, more preferably 0.1 atomic% or more and 2 atomic% or less.

The element M1 contributes to lowering the crystallization heating temperature of the quenched alloy. The composition ratio 1 of the element M1 is 0.01
If it is less than atomic%, the effect of lowering the crystallization heat generation temperature is reduced, which is not preferable. On the other hand, if the composition ratio 1 of the element M1 exceeds 0.4 atomic%, the crystallization exothermic temperature of the boride phase and the crystallization exothermic temperature of the R ₂ Fe ₁₄ B-type compound overlap to obtain good magnetic properties. Can not be. Therefore, the preferable range of the composition ratio 1 of the element M1 is 0.01 ≦ l ≦ 0.
4.

The element M2 contributes to raising the crystallization heating temperature of the quenched alloy. The composition ratio m of the element M2 is 0.05
If it is out of the range of at least 5 atomic%, the effect of increasing the crystallization heating temperature is reduced. Composition ratio m of element M2
Is preferably in a range of 0.05 ≦ m ≦ 5.

As another metal element, at least one element M3 selected from the group consisting of Cr, V, Mn, and Ti may be added. This element M3 contributes to improvement of the coercive force. However, the composition ratio n of the element M3 is 0.01
If the content is less than 7 atomic%, the effect of improving the coercive force is not sufficiently exhibited, and if the content exceeds 7 atomic%, the residual magnetic flux density B
_r decreases, and the squareness of the demagnetization curve also deteriorates. Therefore, the composition ratio m of the element M2 is preferably 0.01 ≦ n ≦ 7, and more preferably 0.05 ≦ n ≦ 5.

Q is composed of B (boron) and C (carbon) obtained by partially substituting B. B is an element necessary for both the soft magnetic phase (for example, Fe ₃ B) and the hard magnetic phase (for example, R ₂ Fe ₁₄ B). The composition ratio y of Q is 15 to 2
If the content is out of the range of 5 atomic%, desired permanent magnet properties are not exhibited.
It is preferably 25. Further, if Q is out of this composition range, the melting point will increase, and it will be necessary to increase the melting temperature and the heat retention temperature of the hot water storage container, and the amorphous forming ability will also decrease, making it difficult to obtain the desired rapidly quenched alloy structure. A more preferable range of the composition ratio y of Q is 17 ≦ z ≦ 20.

The balance of the above elements is T, ie, Fe,
At least one element selected from the group consisting of Co and Ni. Co substitutes for a part of Fe to improve the Curie temperature. The rise in the Curie temperature reduces the dependence of the magnetic properties on temperature change, and stabilizes the magnetic properties. Partial replacement of Fe with Co also has the function of improving the viscosity of the molten alloy and contributes to the stabilization of the molten metal falling rate. A part of Fe may be replaced by Ni instead of or together with Co. The proportion of Co or Ni to the entire T is preferably 0 to 50 atomic%, and more preferably 0.01 to 30 atomic%.

Next, a preferred embodiment of the present invention will be described with reference to the drawings.

In the present embodiment, for example, a raw material alloy is manufactured using a quenching device shown in FIG. In order to prevent oxidation of the raw material alloy containing the rare-earth elements R and Fe that are easily oxidized, the alloy manufacturing process is performed in an inert gas atmosphere. As the inert gas, a rare gas such as helium or argon or nitrogen can be used. Note that since nitrogen easily reacts with the rare earth element R, a rare gas such as helium or argon is preferably used.

[Quenching Apparatus] The apparatus shown in FIG. 3 is provided with a raw alloy melting chamber 1 and a quenching chamber 2 capable of maintaining a vacuum or inert gas atmosphere and adjusting the pressure.

The melting chamber 1 is a melting furnace 3 for melting the raw material 20 blended to have the above-described magnet alloy composition at a high temperature.
And a hot water storage container 4 having a tapping nozzle 5 at the bottom, and a compounding material supply device 8 for supplying the compounding material into the melting furnace 3 while suppressing the entry of the atmosphere. The hot water storage container 4 has a heating device (not shown) that stores the molten metal 21 of the raw material alloy and can maintain the temperature of the molten metal at a predetermined level.

The quenching chamber 2 contains the molten metal 2 discharged from the tapping nozzle 5.
1 is provided with a rotary cooling roll 7 for rapidly cooling and solidifying 1.

In this apparatus, the atmosphere and the pressure in the melting chamber 1 and the quenching chamber 2 are controlled within a predetermined range. For this purpose, the atmosphere gas supply ports 1b, 2b, and 8b and the gas exhaust ports 1a, 2a, and 8a are provided at appropriate locations in the apparatus. In particular, the gas exhaust port 2a is connected to a pump in order to control the absolute pressure in the quenching chamber 2 within a range from vacuum to 50 kPa.

The melting furnace 3 can be tilted, and the molten metal 21 is appropriately poured into the hot water storage container 4 via the funnel 6. Molten 21
Is heated in the hot water storage container 4 by a heating device (not shown).

The hot water outlet nozzle 5 of the hot water storage container 4 is disposed on the partition wall between the melting chamber 1 and the quenching chamber 2.
Flow down to the surface of the cooling roll 7 located below. The orifice diameter of the tapping nozzle 5 is, for example, 0.5 to 2.0 m.
m. When the viscosity of the molten metal 21 is large, the molten metal 21 does not easily flow in the tapping nozzle 5. However, in this embodiment, since the quenching chamber 2 is maintained at a lower pressure state than the melting chamber 1, the melting chamber 1 and the quenching chamber 2 A pressure difference is formed between the
The hot water is run smoothly.

The cooling roll 7 is made of Cu, Fe, or Cu.
It is preferably formed from an alloy containing Fe or Fe. If the cooling roll is made of a material other than Cu or Fe, the releasability of the quenched alloy from the cooling roll deteriorates, and the quenched alloy may be wound around the roll, which is not preferable. The diameter of the cooling roll 7 is, for example, 300 to 500 mm. The water cooling capacity of the water cooling device provided in the cooling roll 7 is calculated and adjusted according to the solidification latent heat and the amount of hot water per unit time.

According to the apparatus shown in FIG.
kg of the raw material alloy can be rapidly solidified in 10 to 20 minutes. The quenched alloy thus formed is, for example, an alloy ribbon (alloy ribbon) 22 having a thickness of 20 to 40 μm and a width of 2 to 3 mm.

[Quenching Method] First, a molten metal 21 of a raw material alloy represented by the above-described composition formula is prepared and stored in the hot-water storage container 4 of the melting chamber 1 in FIG. Next, the molten metal 21 is supplied to the tapping nozzle 5.
From the water-cooled roll 7 in a reduced-pressure Ar atmosphere, is rapidly cooled by contact with the water-cooled roll 7, and solidifies. As the rapid solidification method, it is necessary to use a method capable of controlling the cooling rate with high accuracy.

In the present embodiment, when cooling and solidifying the molten metal 21, the cooling rate is preferably set to 10 ² to 10 ⁷ ° C / sec.

The time during which the molten alloy 21 is cooled by the cooling roll 7 corresponds to the time from contact of the alloy with the outer peripheral surface of the rotating cooling roll 7 until the alloy is separated, during which time the temperature of the alloy decreases. , Coagulates. Thereafter, the solidified alloy leaves the cooling roll 7 and flies in an inert atmosphere. The alloy is deprived of heat by the ambient gas while flying in the form of a ribbon, which further reduces its temperature.

In this embodiment, the roll surface speed is set to 7 m /
The quenched alloy ribbon in an almost amorphous state is produced by adjusting the thickness within a range of not less than second and not more than 30 m / sec. If the roll surface peripheral speed is less than 7 m / sec, a crystal phase is generated and grown, and the desired nanocomposite magnet characteristics cannot be obtained, which is not preferable. On the other hand, if the roll surface peripheral speed exceeds 30 m / sec, the entire rapidly solidified alloy becomes an amorphous phase. Therefore, when a subsequent crystallization heat treatment step is performed, the crystallization process proceeds rapidly, and the structure is controlled. Is not preferable because it becomes difficult.

The quenching method of the molten alloy used in the present invention is not limited to the above-described single roll method, but may be a twin roll method, a gas atomizing method, a strip casting method, or a cooling method combining a roll method and a gas atomizing method. It may be a law.

[Heat Treatment] In this embodiment, the heat treatment is performed in an argon atmosphere. Preferably, the heating rate is 5 ° C.
After holding at a temperature of 550 ° C. or more and 850 ° C. or less for 30 seconds or more and 20 minutes or less, the temperature is cooled to room temperature. By this heat treatment, fine crystals of the metastable phase precipitate and grow in the amorphous phase, and a nanocomposite structure is formed. According to the present invention, the crystal growth temperature of the Fe ₃ B phase or the compound phase having the R ₂ Fe ₂₃ B type crystal structure is controlled by the action of M 1 or M 2, and a uniform fine particle suitable for exhibiting high magnetic properties is obtained. Crystals grow.

The heat treatment atmosphere is used to prevent oxidation of the alloy.
Ar gas or N under 50 kPa _TwoInert such as gas
Gas is preferred. Heat treatment in a vacuum of 0.1 kPa or less
You may go.

The quenched alloy before the heat treatment slightly contains metastable phases such as Fe ₃ B phase, Fe ₂₃ B ₆ , R ₂ Fe ₁₄ B phase and R ₂ Fe ₂₃ B ₃ phase in addition to the amorphous phase. It may be. In the case of the present embodiment, R ₂ Fe
_{The 23} B ₃ phase disappears and the R ₂ Fe ₁₄ B phase and the Fe ₃ B phase grow. Then, a homogeneous microstructure (nanocomposite structure) having a final average crystal grain size of 1 nm or more and 50 nm or less and a standard deviation σ of about 10 nm or less is obtained. From the viewpoint of improving the magnetic properties, the average of the crystal grain size is 1 nm or more and 2
More preferably, it is within a range of 1 nm or less.

In the case of this embodiment, even when a soft magnetic phase such as α-Fe is present, the soft magnetic phase and the hard magnetic phase are magnetically coupled by the exchange interaction, so that excellent magnetic properties are obtained. Be demonstrated.

Before the heat treatment, the quenched alloy ribbon may be roughly cut or pulverized.

After the heat treatment, the obtained magnet alloy is pulverized,
If magnet powder (magnetic powder) is produced, various bond magnets can be produced from the magnetic powder by a known process.
When producing a bonded magnet, the alloy magnetic powder is mixed with an epoxy resin or a nylon resin and molded into a desired shape. At this time, another type of magnetic powder, for example, Sm-Fe
-N-based magnetic powder or hard ferrite magnetic powder may be mixed.

Various rotating machines such as motors and actuators can be manufactured using the above-described bonded magnets.

When the iron-based permanent magnet alloy powder of the present invention is used for an injection-molded bonded magnet, it is preferable to pulverize the powder so as to have a particle size of 150 μm or less, more preferably 1 μm or more and 100 μm or less. It is. When used for compression-molded bonded magnets, the particle size is 30.
It is preferable that the powder is pulverized so as to have a particle size of 0 μm or less. A more preferred range is 50 μm or more and 150 μm.
It is as follows.

(Examples and Comparative Examples) Hereinafter, Examples and Comparative Examples of the present invention will be described in detail.

Sample No. 1 to No. For each of 6,
Using materials of Nd, Fe, Co, and B having a purity of 99.5% or more, the materials were weighed so that the total amount was 15 g, and then they were put into a quartz crucible. Sample No. 1 to No. The composition of No. 6 was as shown in Table 1. Here, the sample No. 1 to No. Sample No. 4 corresponds to an example of the present invention, and 5 to 6 correspond to comparative examples.

[0078]

[Table 1]

In Table 1, for example, “Nd3.5Tb1” in the column labeled “R” indicates that 3.5 atomic% of Nd and 1.0 atomic% of Tb were added, and “B” “18.5” in the displayed column is 18.5 atomic% of B
(Boron) was added.

Since the quartz crucible used for producing the molten metal has an orifice having a diameter of 0.8 mm at the bottom, the above-mentioned raw material is melted in the quartz crucible and then becomes a molten alloy and is dropped from the orifice downward. Will be. Dissolution of raw materials
The high-frequency heating method was used in an argon atmosphere at a pressure of 1 to 3 kPa. In this embodiment, the molten metal temperature is set to 13
The temperature was set at 50 ° C.

By pressurizing the surface of the molten alloy with Ar gas, the molten metal was jetted to the outer peripheral surface of a pure copper roll located 0.7 mm below the orifice. The roll rotates at high speed while cooling the inside so that the temperature of the outer peripheral surface is maintained at about room temperature. For this reason, the molten alloy dropped from the orifice is blown in the peripheral speed direction while being in contact with the roll peripheral surface and removing heat. Since the molten alloy is continuously dropped on the roll peripheral surface through the orifice, the alloy solidified by quenching is a ribbon (width: 2 to 3 mm, thickness: 20 to 30 μ) elongated in a thin strip shape.
m).

In the case of the rotating roll method (single roll method) employed in this embodiment, the cooling rate is defined by the roll peripheral speed and the amount of molten metal flowing down per unit time. The amount of flow depends on the orifice diameter (cross-sectional area) and the pressure of the molten metal. In the embodiment, the diameter of the orifice is 0.8 mm, and the injection pressure of the molten metal is 13 mm.
The flow rate was about 0.5 to 1 kg / min. In this embodiment, the roll surface speed Vs is set to 20 m /
Set to seconds.

In order to obtain a rapidly solidified alloy in which the amorphous phase accounts for 50% by volume or more, the cooling rate should be 10 ² to 10 ^7.
C./sec is preferable, and in order to achieve a cooling rate in this range, the roll peripheral speed is preferably set to 9 m / sec or more.

The DSC profile showing the crystallization exothermic temperature peak was measured for the quenched alloy ribbon thus obtained. FIG. 4 shows a sample No. which is an example of the present invention. 1-2,
And Sample No. as a comparative example. 5 is a graph showing a DSC profile of Sample No. 5; The low temperature peak of the curve is F
The exothermic temperature peak of crystallization of e ₃ B is shown, and the peak on the higher temperature side is the exothermic temperature peak of crystallization of R ₂ Fe ₁₄ B (indicated by “arrow” in the graph).

As can be seen from FIG. 4, in the comparative example,
_Since the crystallization exothermic temperature of the 3B phase was too high, Fe ₃ B
The crystallization exothermic temperature peaks of the phase and the R ₂ Fe ₁₄ B phase are too close to each other, and the separation of both peaks is insufficient. For this reason, in the comparative example, R ₂ Fe ₁₄ B before crystallization of the Fe ₃ B phase is completed.
The crystallization of the phase progresses, and it becomes impossible to sufficiently achieve the refinement and uniformization of the structure.

Next, the sample No. The heat treatment step of holding the rapidly solidified alloys 1 to 6 at the temperature shown in Table 1 for 6 to 10 minutes was performed, and after cooling to room temperature, the magnetic properties were measured. The measurement was performed using a VSM after cutting the heat-treated alloy ribbon into a length of 3 to 5 mm. Table 2 shows the measurement results.

[0087]

[Table 2]

As can be seen from Table 2, the embodiment (No. 1)
To 4) show superior magnetic properties as compared with the comparative examples (Nos. 5 to 6).

The structure of the alloy after the crystallization heat treatment was observed using a transmission electron microscope. Table 2 shows the average crystal grain size D obtained by this observation. As can be seen from Table 2, the average crystal grain size D in the comparative example exceeds 80 nm, whereas the average crystal grain size D in the examples is less than 50 nm.

[0090]

According to the present invention, the crystallization exothermic temperature of each constituent phase can be controlled within a desired temperature range on the basis of a new alloy design technique which has not been known so far. Can be uniformly refined, thereby providing an iron-based alloy magnet having excellent characteristics.

[Brief description of the drawings]

FIG. 1 shows a case where a part of Nd (atomic number A = 60) is replaced by another rare earth element (atomic number A = 57 to 59, 61 to 71), and the added amount x ′ of the rare earth element and Fe ₃ B 4 is a graph showing a relationship between a phase and a crystallization exothermic temperature.

FIG. 2 shows a case where a part of Nd (atomic number A = 60) is replaced with another rare earth element (atomic number A = 57 to 59, 61 to 71), and the added amount x ′ of the rare earth element and R ₂ Fe ₁₄
4 is a graph showing the relationship between the B phase and the crystallization heat generation temperature.

FIG. 3 (a) is a cross-sectional view showing an example of the entire configuration of an apparatus used in a method for producing a quenched alloy for a microcrystalline iron-based alloy magnet according to the present invention, and FIG. FIG.

FIG. 4 is a graph showing DSC curves of an example (sample Nos. 1 and 2) and a comparative example (sample No. 5).

[Explanation of symbols]

 1b, 2b, 8b, and 9b Atmospheric gas supply ports 1a, 2a, 8a, and 9a Gas exhaust ports 1 Melting chamber 2 Quenching chamber 3 Melting furnace 4 Hot water storage tank 5 Hot water nozzle 6 Roth 7 Rotary cooling roll 21 Melt 22 Alloy ribbon

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01F 1/053 H02K 15/03 C H02K 15/03 H01F 1/04 HAF term (Reference) 4K018 AA27 BA18 BB07 BC01 BD01 KA46 5E040 AA03 AA04 AA19 BD03 CA01 HB11 NN01 NN06 NN18 5H622 AA03 DD04 DD06 QA02 QA03

Claims (14)

[Claims] 1. A composition formula _{R x T (100-xylm)} Q y M1 l M
2 _m (at%) (R = La, Ce, Pr, N
d, Pm, Sm, Eu, Gd, Tb, Dy, Ho, E
two or more elements selected from the group consisting of r, Tm, Yb, and Lu, T = at least one element selected from the group consisting of Fe, Co, and Ni, Q = B and C
At least one element selected from the group consisting of
= At least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb, M2 = Nb, Mo,
At least one element selected from the group consisting of Ti and Zr), symbols x, y, l, and m defining the composition range
Satisfies the following relationship: 1 ≦ x ≦ 6, 15 ≦ y ≦ 25, 0.01 ≦ l ≦ 0.4, and 0.05 ≦ m ≦ 5, at least two crystal phases including at least a hard magnetic phase Is a method for producing an iron-based permanent magnet alloy containing a mixture of the elements R, M1, and M2, and adjusting the composition ratio and the crystallization exothermic temperature of one crystal phase to 585 ° C. to 615 ° C. And a method for producing an iron-based permanent magnet alloy in which the crystallization exothermic temperature of another crystal phase is controlled to 610 ° C. to 640 ° C. 2. The composition formula is (Nd _{x−x ′} R ′ _{x ′} ) T
_{(100-xylm) Q y M1} l M2 m is represented by (at%) (R '= Pm, Sm, Eu, Gd, Tb, Dy, Ho,
At least one element selected from the group consisting of Er, Tm, Yb, and Lu, T = Fe, Co, and Ni
At least one element selected from the group consisting of:
At least one element selected from the group consisting of B and C; M1 = at least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb; M2 = N
b, Mo, Ti, and at least one element selected from the group consisting of Zr), a symbol x for limiting the composition range,
x ′, y, l, and m satisfy the following relationships: 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25, 0.01 ≦ l ≦ 0.4, and 0. 05 ≦ m ≦ 5, a method for producing an iron-based permanent magnet alloy in which two or more crystal phases including at least a hard magnetic phase are mixed, wherein at least a part of Nd is a rare earth element R ′ having an atomic number larger than Nd. The crystallization exothermic temperature of each of the crystal phases is increased by substituting, thereby controlling the crystallization exothermic temperature of one crystal phase to 585 ° C. to 615 ° C. and the crystallization exothermic temperature of the other crystal phases. 610 ° C-6
A method for producing an iron-based permanent magnet alloy controlled at 40 ° C. 3. The composition formula is (Nd _{x−x ′} R ″ _{x ′} ) T
_(100-xylm) Q _y M1 _l M2 _m (at%) (R ″ = at least one element selected from the group consisting of La, Ce, and Pr, T = Fe, Co, and N
at least one element selected from the group consisting of i, Q
= At least one element selected from the group consisting of B and C, M1 = at least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb, M2 =
At least one element selected from the group consisting of Nb, Mo, Ti, and Zr), and the symbols x, x ', y, l, and m that limit the composition range satisfy the following relationship: 1 ≦ x ≦ 6 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25, 0.01 ≦ l ≦ 0.4, and 0.05 ≦ m ≦ 5, iron in which two or more crystal phases including at least a hard magnetic phase are mixed A method for producing a base permanent magnet alloy, comprising reducing at least a portion of Nd with a rare earth element R ″ having a smaller atomic number than Nd, thereby lowering the crystallization exothermic temperature of each of the crystal phases. The exothermic crystallization temperature of one crystal phase is controlled at 585 ° C. to 615 ° C., and the exothermic crystallization temperature of the other crystal phase is 610 ° C. to 6 ° C.
A method for producing an iron-based permanent magnet alloy controlled at 40 ° C. 4. An iron-based boride phase and an R ₂ T ₁₄ B-type compound phase as the two or more crystal phases, wherein the iron-based boride phase has a crystallization exothermic temperature of T ₁ , and the R ₂ T ₁₄
The exothermic crystallization temperature of the B-type compound phase is T ₂ , the atomic number of the rare earth element substituted with Nd is A, and the exothermic crystallization temperature of the iron-based boride phase when X ′ is 0 at% is T _{1 (x ′ = 0)} , x '
Is 0 at%, the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase is T _{2 (x ′ = 0),} and T ₁ = α ₁ (A−60) + T _{1 (x ′ = 0)} (0 <α ₁ ≦ 1
0) T ₂ = α ₂ (A−60) + T _{2 (x ′ = 0)} (0 <α ₂ ≦ 2
The method for producing an iron-based permanent magnet alloy according to claim 2 or 3, which satisfies 0). 5. An iron-based boride phase and an R ₂ T ₁₄ B-type compound phase as the two or more crystal phases, wherein the iron-based boride phase has a crystallization exothermic temperature of T ₁ and an R ₂ T. ₁₄
The crystallization exothermic temperature of the B-type compound phase is T ₂ , the atomic number of the i-th element (1 <i ≦ N) of the N rare earth elements substituted with Nd is A _i , and x ′ is 0 at%. The exothermic crystallization temperature of the iron-based boride phase is T _{1 (x ′ = 0)} , and x ′ is 0 at%.
T ₁ = Σα _i1 (A _i −60) + T _{1 (x ′ = 0)} (0 ₎ where T _{2 (x ′ = 0)} is the heat of crystallization of the R ₂ T ₁₄ B-type compound phase at <Α
_i1 ≦ 10) T ₂ = Σα _i2 (A _i −60) + T _{2 (x ′ = 0)} (0 <α
_{4. The} method for producing an iron-based permanent magnet alloy according to claim 2, wherein _i2 ≦ 20) is satisfied. 6. The composition formula is (Pr _{x-x ′} R ′ _{x ′} ) T
_(100-xylm) Q _y M1 _l M2 _m (at%) (R ′ = Nd, Sm, Eu, Gd, Tb, Dy, Ho,
At least one element selected from the group consisting of Er, Tm, Yb, and Lu, T = Fe, Co, and Ni
At least one element selected from the group consisting of:
At least one element selected from the group consisting of B and C; M1 = at least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb; M2 = N
b, Mo, Ti, and at least one element selected from the group consisting of Zr), a symbol x for limiting the composition range,
x ′, y, l, and m satisfy the following relationships: 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25, 0.01 ≦ l ≦ 0.4, and 0. 05 ≦ m ≦ 5, a method for producing an iron-based permanent magnet alloy in which two or more crystal phases including at least a hard magnetic phase are mixed, wherein at least part of Pr is a rare earth element R ′ having an atomic number larger than Pr. The crystallization exothermic temperature of each of the crystal phases is increased by substituting with each other, whereby the crystallization exothermic temperature of one crystal phase is controlled to 585 ° C. to 615 ° C., and the crystallization exothermic temperature of the other crystal phases is decreased. 610 ° C-640 ° C
Production method of iron-based permanent magnet alloy controlled in a controlled manner. 7. The composition formula is (Pr _{x-x ′} R ″ _{x ′} ) T
Selected from _{the (100-xylm) Q y M1} l M2 m is represented by (at%) (R "= La and at least one element selected from the group consisting of Ce, T = Fe, the group consisting of Co, and Ni At least one element selected from the group consisting of: Q = B and C;
M1 = at least one element selected from the group consisting of Cu, Ga, Si, Al, and Pb, M2 = Nb, M
o, at least one element selected from the group consisting of Ti, and Zr), symbols x, x ', which limit the composition range
y, l, and m satisfy the following relationship: 1 ≦ x ≦ 6, 0 <x ′ ≦ 4.5, 15 ≦ y ≦ 25, 0.01 ≦ l ≦ 0.4, and 0.05 ≦ m ≦ 5, a method for producing an iron-based permanent magnet alloy in which two or more crystal phases including at least a hard magnetic phase are mixed, wherein at least a part of Pr is replaced by a rare earth element R ″ having an atomic number smaller than Pr. This lowers the crystallization exothermic temperature of each of the crystal phases, thereby controlling the crystallization exothermic temperature of one crystal phase to 585 ° C. to 615 ° C. and the crystallization exothermic temperature of the other crystal phases to 610 ° C. to 610 ° C. 640 ° C
Production method of iron-based permanent magnet alloy controlled in a controlled manner. 8. An iron-based boride phase and an R ₂ T ₁₄ B-type compound phase as the two or more crystal phases, wherein the iron-based boride phase has a crystallization exothermic temperature of T ₁ and an R ₂ T. ₁₄
The exothermic crystallization temperature of the B-type compound phase is T ₂ , the atomic number of the rare earth element substituted with Pr is A, and the exothermic crystallization temperature of the iron-based boride phase when x ′ is 0 at% is T _{1 (x ′ = 0)} , x '
When the crystallization exothermic temperature of the R ₂ T ₁₄ B type compound phase at 0 at% is T _{2 (x ′ = 0)} , T ₁ = α ₁ (A−59) + T _{1 (x ′ = 0)} (0 <α ₁ ≦ 1
0) T ₂ = α ₂ (A−59) + T _{2 (x ′ = 0)} (0 <α ₂ ≦ 2
The method for producing an iron-based permanent magnet alloy according to claim 6 or 7, which satisfies 0). 9. An iron-based boride phase and an R ₂ T ₁₄ B-type compound phase as the two or more crystal phases, wherein the iron-based boride phase has a crystallization exothermic temperature of T ₁ and an R ₂ T. ₁₄
The crystallization exothermic temperature of the B-type compound phase is T ₂ , the atomic number of the i-th element (1 <i ≦ N) of the N rare earth elements substituted with Pr is A _i , and x ′ is 0 at%. The exothermic crystallization temperature of the iron-based boride phase is T _{1 (x ′ = 0)} , and x ′ is 0 at%.
T ₁ = Σα _i1 (A _i −59) + T _{1 (x ′ = 0)} (0 ₎ where T _{2 (x ′ = 0)} is the heat of crystallization of the R ₂ T ₁₄ B type compound phase at <Α
_i1 ≦ 10) T ₂ = Σα _i2 (A _i −59) + T _{2 (x ′ = 0)} (0 <α
_{8. The} method for producing an iron-based permanent magnet alloy according to claim 6, wherein _i2 ≦ 20) is satisfied. 10. An iron-based permanent magnet that forms an alloy structure capable of exhibiting hard magnetic properties by subjecting an iron-based rapidly solidified alloy whose volume ratio is at least 90% to an amorphous structure to a heat treatment for crystallization. An iron-based permanent magnet alloy for controlling the crystallization exothermic temperature of the rapidly solidified alloy by changing the combination of the rare earth element R, the additional elements M1 and M2, and the content of the alloy composition. Manufacturing method. 11. A method for producing a microcrystalline iron-based alloy magnet having two or more metastable phases including a hard magnetic phase, comprising: a rare earth element R (R is Pr or Nd);
Preparing an iron-based alloy containing a rare-earth element R ′ having a larger atomic number than R ′ and a rare-earth element R ″ having a smaller atomic number than the rare-earth element R; and quenching the molten iron-based alloy, Producing a quenched alloy in which the amorphous phase occupies 90% or more of the whole by volume; and a heat treatment step of heating the quenched alloy to promote crystal growth in the iron-based alloy. R, rare earth element R ′, and rare earth element R ″
A method for producing an iron-based permanent magnet alloy which forms a microstructure having an average crystal grain size of 1 nm or more and 50 nm or less after the heat treatment step by adjusting the composition ratio of the iron-based permanent magnet alloy. 12. The composition ratio of the rare earth element R, the rare earth element R ′, and the rare earth element R ″ is such that the crystallization exotherm temperature of the phase having the lowest crystallization exotherm temperature and the crystallization exotherm temperature of the metastable phase are the lowest. The method for producing an iron-based permanent magnet alloy according to claim 11, wherein the difference from the crystallization heating temperature of the high phase is adjusted to 5 ° C. or more and 25 ° C. or less. 13. A bonded magnet formed by using a powder of an iron-based permanent magnet alloy produced by the production method according to claim 1. 14. A rotating machine provided with the bonded magnet according to claim 13.