JPH11158588A - Raw alloy for manufacture of rare earth magnetic powder, and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a raw alloy for manufacture of a rare earth magnetic powder. SOLUTION: When the symbol R refers hereinafter to at least one kind among rare earth elements including Y, the symbol T refers hereinafter to Fe or a component which is composed essentially of Fe and in which part of Fe is substituted by Co or Ni, and the symbol M refers hereinafter to B or a component in which part of B is substituted by C, this raw alloy has a structure in which a phase (hereinafter referred to as an internal dispersed phase), constituted so that a g-phase having a crystal structure capable of being in a coherent relation with an MR hydride consisting of an M-containing R hydride is dispersed in the inner part of a phase of the above MR hydride having 0.002-20 μm average grain size, is dispersed in the matrix of an R-T-M alloy composed essentially of R, T, and M into island state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a material alloy for producing a rare earth magnet powder and a method for producing the same. The rare earth magnet powder obtained by dehydrogenating the material alloy for producing a rare earth magnet powder has an organic binder. Alternatively, a bonded magnet can be manufactured by bonding with a metal binder, or a hot pressed magnet or a hot isostatic pressed magnet can be manufactured by hot pressing or hot isostatic pressing, respectively.

[0002]

2. Description of the Related Art To manufacture a rare earth magnet powder having a texture of a fine rare earth intermetallic compound phase, R ₂ Fe ₁₄ B
The intermetallic compound phase is subjected to R ₂ F in hydrogen at 500 to 1000 ° C.
e ₁₄ B phase is made to absorb hydrogen, and RH ₂ , Fe and Fe
_{When the} phase is transformed to the 3B phase and dehydrogenation is subsequently performed in the same temperature range, the 3 phases of RH ₂ , Fe and Fe ₂ B generated by the hydrogen absorption are re-transformed to the R ₂ Fe ₁₄ B phase. And a recrystallized texture of fine R ₂ Fe ₁₄ B intermetallic compound,
It is known that excellent magnetic properties are exhibited [see Japanese Unexamined Patent Publication (Kokai) No. 3-129702, Summary of General Lectures of Autumn Meeting of the Japan Institute of Metals (1989, P367)].

[0003] This production method comprises the steps of hydrogenation and phase decomposition of an R ₂ Fe ₁₄ B intermetallic compound phase.
), Dehydrogenation and Recombina
), which is called an HDDR processing method. This method includes at least one rare earth element (hereinafter, referred to as R) containing Y, Fe, or Fe as a main component and a part as Co. , Ni (hereinafter referred to as T), and an alloy (hereinafter referred to as R-) containing B or a component obtained by substituting a part of B with C (hereinafter referred to as M) as a main component. It is also known that a rare earth magnet powder having a recrystallized texture with more excellent magnetic anisotropy can be obtained.

[0004]

However, if the R-T-M alloy is subjected to a hydrogen absorption treatment in a temperature range of 500 ° C. to 1000 ° C. and then to a dehydrogenation treatment in that temperature range, it is always treated at a high temperature. In some cases, abnormal grain growth occurs, and a uniform and fine recrystallized texture cannot be obtained. Therefore, a rare earth magnet powder having sufficient magnetic properties may not be obtained.

[0005]

Means for Solving the Problems Accordingly, the present inventors have
As a result of conducting research to produce a rare earth magnet powder that is even better than before, it was found that (a) an MR hydride phase having an average particle size of 0.002 to 20 μm in an RTM alloy base material,
A phase in which a phase having a crystal structure that can be in a consistent relationship with the MR hydride (hereinafter, referred to as a g phase) is present in a dispersed state (hereinafter, a g phase is dispersed in the MR hydride phase). When a raw alloy for producing a rare earth magnet powder having a structure in which a phase is referred to as an internal dispersed phase) is dispersed in the form of islands, and the raw alloy for producing the rare earth magnet powder is subjected to dehydrogenation treatment, a more excellent magnetic property than before is obtained. (B) The raw material alloy for producing a rare earth magnet powder of the above (a) can further obtain a rare earth magnet powder having characteristics.
A phase having a tetragonal crystal structure of 85 nm and c = 0.90 to 1.10 nm and a composition ratio of (R + M) / T of 0.13 to 0.30 (hereinafter referred to as TE phase) is dispersed. It has been found that when a raw material alloy for producing a rare earth magnet powder having the above structure is subjected to a dehydrogenation treatment, a rare earth magnet powder having more excellent magnetic properties than before can be obtained.

The present invention has been made on the basis of the above research results. (1) An MR hydride phase having an average particle size of 0.002 to 20 μm is contained in a base of an RTM alloy. A raw alloy for producing a rare earth magnet powder having a structure in which a g-phase having a crystal structure that can be in a consistent relationship with the MR hydride is dispersed therein in an island shape; 2) A raw material for producing a rare earth magnet powder having a structure in which a g phase is dispersed inside an MR hydride phase and a structure in which a TE phase is dispersed in a base of an R-T-M alloy. Alloy, (3) The rare earth element according to (2), wherein the TE phase is dispersed in a state surrounding a part of an internal dispersed phase having a structure in which a g phase is dispersed in the MR hydride phase. Material alloy for producing magnet powder.

[0007] The size of the MR hydride phase is an average particle size:
0.002 to 20 μm (preferably 0.002 to 3 μm
m, more preferably within a range of 0.002 to 1 μm), and the finer the particle, the more preferable.
If it is smaller than 2 μm, an internal dispersed phase consisting of an MR hydride phase and a g phase will not be formed, which is not preferable as a raw material alloy for producing a rare earth magnet powder. The MR hydride phase constituting the internal dispersed phase has an M content of 0.1 to 50 atomic%.
Is preferable, and M is more preferably a hydride of R containing 0.1 to 50 atomic% and containing T and A of 30 atomic% or less (not including 0).

The “g phase having a crystal structure that can be in a consistent relationship with the MR hydride” is, specifically, a structure in which the crystal structure of the MR hydride is similar to a face-centered cubic lattice.
The crystal structure of the g-phase has a plane spacing substantially equal to the low-index plane spacing similar to the face-centered cubic lattice of the MR hydride, which indicates that the crystal structure of the MR hydride and the crystal structure of the g-phase are consistent. It means that they are in a relationship. Among at least one or more rare earth elements including Y contained in the raw material alloy for producing a rare earth magnet powder of the present invention, R is particularly preferably Nd, Pr, Dy, La, or Ce.

The structure of the raw material alloy for producing a rare earth magnet powder of the present invention will be described with reference to the drawings. FIG. 1 is a sketch of the structure of the raw material alloy for producing a rare earth magnet powder of the above (1) of the present invention. From FIG. 1, it can be seen that the g phase is dispersed in the form of fine spots inside the MR hydride phase to form an internal dispersed phase, and that the internal dispersed phase has a structure in which the internal dispersed phase is dispersed in an island shape in the matrix. FIG. 2 shows (2) and (3) of the present invention.
FIG. 4 is a sketch drawing of the structure of a raw material alloy for producing a rare earth magnet powder. From FIG. 2, it can be seen that the g phase is dispersed in the form of fine spots inside the MR hydride phase to form an internal dispersed phase, and this internal dispersed phase is dispersed in the form of islands in a matrix with the TE phase partially surrounded. It can be seen that the organization has a certain organization. 1 and 2 is mainly composed of M (for example, Fe, Fe-C
o, Fe ₂ B, (Fe, Co) ₂ B, etc.). The raw material alloy for producing a rare earth magnet powder having the structure shown in FIGS.
When the dehydrogenation treatment is forcibly performed by raising the temperature to a predetermined temperature within the range of 1000 ° C. and maintaining the temperature, it is excellent in magnetic anisotropy having a recrystallized texture of fine R ₂ T ₁₄ M type intermetallic compound phase. Rare earth magnet powder can be manufactured, by bonding the rare earth magnet powder with an organic binder or a metal binder, or at a temperature of 600 to 900 ° C.
And hot pressing or hot isostatic pressing to produce a rare earth magnet.

In order to produce the raw material alloy for producing a rare earth magnet powder of the above (1) of the present invention, an R-T-M-based alloy ingot, preferably an R-T-M alloy which has been homogenized at 900 to 1200 ° C. An M-based alloy ingot is prepared, and the temperature of the ingot is increased from room temperature to a predetermined temperature within a range of less than 500 ° C. in a non-oxidizing atmosphere (vacuum atmosphere, inert gas atmosphere, or the like). After holding, temperature: 500-7 in a mixed atmosphere of hydrogen or hydrogen and an inert gas
The temperature is raised to and maintained at a predetermined temperature within a range of 50 ° C., and further, in a hydrogen or mixed atmosphere of hydrogen and an inert gas, at a temperature of 75 ° C.
The R-T-M-based alloy ingot is subjected to a hydrogen occlusion treatment by raising the temperature to a predetermined temperature within the range of 0 to 1000 ° C. and held, and subsequently, the R-T subjected to the hydrogen occlusion treatment is subjected to the hydrogen occlusion treatment. The alloy can be manufactured by subjecting the -M alloy ingot to an inert gas heat treatment maintained at 500 to 1000C in an inert gas atmosphere, and then to a cooling process of cooling to room temperature in an inert gas atmosphere.

In order to produce the raw material alloy for producing a rare earth magnet powder of the above (2) or (3) having a structure in which the TE phase is dispersed according to the present invention, an RTM-based alloy ingot, preferably Prepares an RTM-based alloy ingot that has been homogenized at 900 to 1200 ° C., and the ingot is heated from room temperature to 500 ° C. in a non-oxidizing atmosphere (a vacuum atmosphere, an inert gas atmosphere, or the like). The temperature is raised to a predetermined temperature within the range of less than or less than 750 to 1 in a mixed atmosphere of hydrogen or hydrogen and an inert gas.
The R-T-M alloy ingot is subjected to a hydrogen-absorbing treatment in which hydrogen is absorbed by raising the temperature to a predetermined temperature within the range of 000 ° C., and subsequently, the R-T-M is subjected to the hydrogen-absorbing treatment. Subjecting the system alloy ingot to an inert gas heat treatment at a predetermined temperature in the range of 500 to 1000 ° C. in an inert gas atmosphere, and then to a cooling treatment for cooling to room temperature in the inert gas atmosphere. Can be manufactured.

Accordingly, the present invention provides (4) a method of preparing an RTM-based alloy ingot from room temperature to a temperature:
After the temperature is raised to a predetermined temperature within a range of less than 500 ° C., or after the temperature is raised and held, the temperature is raised to a predetermined temperature within a range of 500 to 750 ° C. in hydrogen or a mixed atmosphere of hydrogen and an inert gas. Then, in a mixed atmosphere of hydrogen or hydrogen and an inert gas, the temperature is raised to a predetermined temperature in the range of 750 to 1000 ° C., and the hydrogen is absorbed in the RTM alloy ingot. And then subjecting the RTM alloy ingot subjected to the hydrogen storage treatment to an inert gas heat treatment at 500 to 1000 ° C. in an inert gas atmosphere. Method for producing a raw material alloy for producing a rare earth magnet powder, which is subjected to a cooling treatment for cooling to room temperature in an atmosphere; (5) heating an RTM-based alloy ingot from room temperature to 500 ° C. in a non-oxidizing atmosphere;
After the temperature is raised to a predetermined temperature up to or less than or equal to and maintained at a predetermined temperature within a range of 750 to 1000 ° C. in hydrogen or a mixed atmosphere of hydrogen and an inert gas. And then subjecting the RTM-based alloy ingot to a hydrogen-absorbing treatment for absorbing hydrogen, and then subjecting the RTM-based alloy ingot subjected to the hydrogen-absorbing treatment to an inert gas atmosphere at a temperature of 500 to 1000 ° C. A method of producing a raw alloy for producing a rare earth magnet powder, which is subjected to an inert gas heat treatment maintained at a predetermined temperature within a range, and then subjected to a cooling treatment of cooling to room temperature in an inert gas atmosphere; (6) the rare earth magnet powder In the method for producing a raw material alloy for production, the R-
The T-M alloy ingot is vacuum or Ar atmosphere,
Temperature: The above-mentioned (4), which is an RT-M-based alloy ingot homogenized by maintaining the temperature at 600 to 1200 ° C.
Or (5) a method for producing a raw material alloy for producing a rare earth magnet powder according to (5).

The inert gas atmosphere in the inert gas heat treatment according to the above (4) or (5), has a pressure of 0.5 to 11 at.
m inert gas atmosphere, and cooling after the inert gas heat treatment is performed up to 500 ° C. at 30 to 500 ° C./min. It is preferable to carry out at a cooling rate of

In the method for producing a raw material alloy for producing a rare earth magnet powder according to (4) and (5) of the present invention, the non-oxidizing atmosphere is a vacuum atmosphere, an inert gas atmosphere, or a vacuum atmosphere and then an inert gas atmosphere. Although there is a combination atmosphere of a vacuum atmosphere and an inert gas atmosphere, it is most preferable to use a vacuum atmosphere or a vacuum atmosphere at the beginning of the temperature raising process in order to remove the adsorption gas on the alloy surface.

FIG. 3 shows a processing pattern of the method (4) for producing a raw material alloy for producing a rare earth magnet powder according to the present invention. In FIG. 3, after raising or maintaining the temperature of the RTM-based alloy in a non-oxidizing atmosphere from room temperature to a predetermined temperature within a range of less than 500 ° C., a hydrogen gas atmosphere or a hydrogen gas atmosphere is used. Temperature in mixed gas atmosphere of inert gas: 500
The temperature is raised to and maintained at a predetermined temperature in the range of 750 ° C. to 750 ° C., and further raised to a predetermined temperature in the range of 750 to 1000 ° C. in a hydrogen gas atmosphere or a mixed gas atmosphere of hydrogen gas and an inert gas. By holding the RTM alloy, hydrogen is absorbed in the RTM alloy to promote phase transformation. Subsequently, the RTM alloy ingot subjected to the hydrogen absorbing treatment is heated in an inert gas atmosphere at a temperature of 500 to 1000. This shows that the inert gas heat treatment is performed at a predetermined temperature in the range of ° C. and then cooled to room temperature in an inert gas atmosphere.

FIG. 4 shows a processing pattern of the method (5) for producing a raw material alloy for producing a rare earth magnet powder according to the present invention. In FIG. 4, after raising or maintaining the temperature of the RTM-based alloy from room temperature to a predetermined temperature within a range of less than 500 ° C. in a non-oxidizing atmosphere, the RTM-based alloy is mixed with a hydrogen gas atmosphere or a hydrogen gas. Temperature: 7 in a mixed gas atmosphere of inert gas
By raising and maintaining the temperature at a predetermined temperature in the range of 50 to 1000 ° C., hydrogen is absorbed in the R-T-M-based alloy to promote the phase transformation, and subsequently, the R-T-M which has been subjected to the hydrogen-absorbing treatment
-Based alloy ingot in an inert gas atmosphere at a temperature of 500
This shows that an inert gas heat treatment is performed at a predetermined temperature in a range of up to 1000 ° C., and then cooled to room temperature in an inert gas atmosphere.

FIG. 3 shows a pattern of the method (4) for producing a material alloy for producing a rare earth magnet powder according to the present invention. FIG. 3 shows a pattern of the method (5) for producing a material alloy for producing a rare earth magnet powder according to the invention (5). Although shown in FIG. 4, the present invention is not limited to this, and variously modified patterns can be adopted.

In the inert gas heat treatment in the method for producing a raw material alloy for producing a rare earth magnet powder of the present invention, the hydrogen-absorbing RTM alloy is subjected to an inert gas atmosphere (pressure: 0) such as Ar gas or He gas. 0.5 to 11 atm, preferably pressure: 1.2 to 11 atm, more preferably 1.2 to 11 atm.
Temperature: 500 to 100 in an inert gas atmosphere of 2 atm)
0 ° C. (preferably 650-950 ° C., more preferably 750-900 ° C.) for 30 seconds-5 ° C.
Time (preferably 1 minute to 1 hour, more preferably 10 minutes
(Minute to 30 minutes). This inert gas heat treatment is performed in an Ar gas atmosphere at a pressure of 1.2 to 2 atm and a temperature of 750 to 900 ° C. for 1 minute to 3 minutes.
It is most preferable to carry out by holding for 0 minutes. This inert gas heat treatment is performed by introducing an inert gas in such a manner that the hydrogen gas atmosphere of the hydrogen storage treatment or the mixed gas atmosphere of the hydrogen gas and the inert gas is replaced with the inert gas.

In the subsequent cooling process, cooling to room temperature is performed by an inert gas (Ar gas).
0 to 30 ° C / min. (Preferably 5
0 to 300 ° C / min. By performing the cooling at the cooling rate of (1), a more excellent raw material alloy can be produced.

The raw material alloy thus obtained can be temporarily stored. This raw material alloy was subjected to an ultimate pressure of 1 Torr.
By performing a dehydrogenation treatment at a predetermined temperature within a range of 500 to 1000 ° C. in a vacuum atmosphere of less than r, hydrogen is forcibly released to sufficiently remove hydrogen, and then inert gas is removed. By cooling from (Ar gas) to room temperature, a rare-earth magnet powder having a fine R ₂ T ₁₄ M type intermetallic compound phase and excellent magnetic anisotropy having a recrystallized texture can be produced.

Starting materials for producing the raw material alloy for producing a rare earth magnet powder of the present invention include a cast alloy, a sintered alloy, a super-quenched alloy, an atomized alloy, a partially or entirely amorphous alloy, a mechanical alloy alloy, Although any alloy such as a co-reduced powder may be used, it is particularly preferable to use a cast alloy, a partially or entirely amorphous alloy or a mechanical alloy alloy.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A molten metal obtained by melting using a high-frequency vacuum melting furnace was cast, and an RTM alloy a to j having a component composition shown in Table 1 was obtained.
From the ingots of the R-T-M-based alloys a to j, and a block having a square of 10 mm or less is produced. The block is placed in a vacuum atmosphere of 2 × 10 ⁻³ Torr or less at a temperature of 113 mm or less.
Homogenization treatment was performed under the conditions of 0 ° C. and holding for 30 hours.

[0023]

[Table 1]

The obtained blocks are subjected to a temperature-raising treatment in which the temperature is raised or raised from room temperature under the conditions shown in Tables 2 to 4, and then kept in a hydrogen atmosphere at the pressures shown in Tables 2 to 4. Hydrogen storage treatment was performed under two-stage holding temperature conditions of temperature 1 and holding temperature 2, followed by inert gas heat treatment under the conditions shown in Tables 2 to 4, and then Ar gas under the conditions shown in Tables 2 to 4. To forcibly cool to room temperature, to produce raw material alloys (hereinafter referred to as raw materials of the present invention) 1 to 30 of the present invention for producing rare earth magnet powder.

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

[Table 4]

The structures of the raw materials 1 to 30 of the present invention were observed with a transmission electron microscope, and the presence or absence of a g layer and the presence or absence of a TE phase in an MR hydride phase composed of an R hydride containing M were observed. And the results are shown in Tables 5 to 7.

Further, the raw materials 1 to 30 of the present invention were stored in the atmosphere at a temperature of 30 ° C. and a humidity of 70% for 60 days, and then 1 ×
A dehydrogenation treatment was performed in a vacuum atmosphere of 10 ^-2 Torr at a temperature of 850 ° C. for 1 hour, followed by rapid cooling with Ar gas and pulverization to produce a rare earth magnet powder of 200 μm or less. Observation of the structure of the rare earth magnet powder revealed that it had a fine recrystallized texture of the R ₂ T ₁₄ M type intermetallic compound phase. This rare earth magnet powder was subjected to orientation treatment in a magnetic field of 40 kOe. The magnetic properties were measured with a magnetic flux meter, and the results are shown in Tables 5 to 7.

[0030]

[Table 5]

[0031]

[Table 6]

[0032]

[Table 7]

Example 2 The R-T- having the component composition shown in Table 1 prepared in Example 1
After subjecting the blocks of the M-based alloys a to j to a temperature increase or a temperature increase from room temperature under the conditions shown in Tables 8 to 10, and then holding them in a hydrogen atmosphere at a pressure shown in Tables 8 to 10, 8
Perform hydrogen storage treatment under the holding temperature conditions shown in
Subsequently, an inert gas heat treatment is performed under the conditions shown in Tables 8 to 10, and then, under the conditions shown in Tables 8 to 10,
The mixture was forcibly cooled to room temperature with a gas,
Was prepared.

[0034]

[Table 8]

[0035]

[Table 9]

[0036]

[Table 10]

The structures of the raw materials 31 to 60 of the present invention were observed with a transmission electron microscope to determine the presence or absence of a g layer and the presence of a TE phase dispersed inside the MR hydride phase. It was shown to. As a result of electron beam EDX analysis of the TE phase observed in the raw materials 31 to 40 of the present invention, the TE phase was a phase having a lattice constant and a composition ratio shown in Table 11.

Furthermore, the raw materials 31 to 60 of the present invention are
After storing for 60 days at a temperature of 30 ° C. and a humidity of 70%,
× 10 ⁻² Torr in a vacuum atmosphere, temperature: 850 ° C., 1
A dehydrogenation treatment was performed under the condition of holding time, and then quenched with Ar gas and then pulverized to produce a rare earth magnet powder of 200 μm or less. Observation of the structure of the rare-earth magnet powder revealed that it had a fine recrystallized texture of the R ₂ T ₁₄ M-type intermetallic compound phase.
And the magnetic properties were measured with a vibrating sample magnetometer, and the results are shown in Tables 11 to 13.

[0039]

[Table 11]

[0040]

[Table 12]

[0041]

[Table 13]

Conventional Example 1 R-T- having the component composition shown in Table 1 prepared in Example 1
Conventional raw materials 1 to 10 were produced by treating the homogenized blocks of the M-based alloys a to j in a hydrogen atmosphere and an inert gas atmosphere under the conditions shown in Table 14.

These conventional materials 1 to 10 were placed in the atmosphere at a temperature of:
After storage at 30 ° C., humidity: 70% for 60 days, 1 × 10
^A dehydrogenation treatment was carried out in a vacuum atmosphere of ^-2 Torr and at a temperature of 850 ° C. for 1 hour, followed by rapid cooling with Ar gas and pulverization to produce a rare earth magnet powder of 200 μm or less. Observation of the structure of the rare earth magnet powder revealed that it had a fine recrystallized texture of the R ₂ T ₁₄ M type intermetallic compound phase. This rare earth magnet powder was subjected to orientation treatment in a magnetic field of 40 kOe. The magnetic properties were measured with a magnetic flux meter, and the results are shown in Table 15.

[0044]

[Table 14]

[0045]

[Table 15]

From the results shown in Tables 1 to 15, raw materials 1, 11, 31, and 41 of the present invention having g phase or g phase and TE phase produced by the method of the present invention using alloy a of Table 1 The magnetic properties of the rare earth magnet powder obtained by dehydrogenating, quenching and pulverizing the powder to 200 μm or less show that the conventional raw material 1 produced by the conventional method using the alloy a shown in Table 1 and the conventional method was used. Then, it is found that the magnetic properties of the rare earth magnet powder obtained by quenching and pulverizing to 200 μm or less are superior to those of the rare earth magnet powder.

Similarly, using each of the alloys b to j in Table 1, the raw material of the present invention having the g phase or the g phase and the TE phase produced by the method of the present invention is subjected to dehydrogenation treatment, quenched, and cooled.
The magnetic properties of the rare-earth magnet powder obtained by pulverizing to less than or equal to 00 μm are obtained by dehydrogenating a conventional raw material produced by a conventional method using each of the same alloys b to j in Table 1.
It can be seen that the magnetic properties of the rare earth magnet powder obtained by quenching and pulverizing to 200 μm or less are superior.

[0048]

As described above, the magnetic properties of the rare earth magnet powder obtained by subjecting the raw material alloy having the g phase or the g phase and the TE phase of the present invention to dehydrogenation treatment are as follows. Since it is superior to the magnetic properties of the rare-earth magnet powder obtained by the treatment, it is possible to provide a rare-earth magnet powder which is superior to the conventional one, and has excellent industrial effects.

[Brief description of the drawings]

FIG. 1 is a structural sketch of a raw material alloy for producing a rare earth magnet powder according to the present invention.

FIG. 2 is a structural sketch of a raw material alloy for producing a rare earth magnet powder according to the present invention.

FIG. 3 is a production pattern diagram of a raw material alloy for producing a rare earth magnet powder according to the present invention.

FIG. 4 is a production pattern diagram of a raw material alloy for producing a rare earth magnet powder of the present invention.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Noriyuki Oki 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Graduate School of Science and Engineering, Kyushu University (72) Noriyuki Kuwano 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Kyushu University Graduate School of Science (72) Inventor Ken Itakura 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Kyushu University Graduate School of Science and Engineering

Claims (13)

[Claims] 1. At least one rare earth element containing Y (hereinafter referred to as R), Fe or a component containing Fe as a main component and partially substituting Co or Ni (hereinafter referred to as T), B or a component obtained by partially replacing B with C (hereinafter referred to as M
) And an alloy containing as a main component (hereinafter, this alloy is referred to as R
-TM-based alloy), the above-mentioned MR hydrogen is contained inside a phase composed of R hydride containing M having an average particle size of 0.002 to 20 µm (hereinafter referred to as MR hydride phase). A structure in which a phase having a crystal structure (hereinafter, referred to as a g-phase) that can be in a coherent relationship with the oxide is dispersed (hereinafter, this phase is referred to as an internally dispersed phase) is dispersed in an island shape. A raw material alloy for producing a rare earth magnet powder, comprising: 2. A composition comprising R, T, and M as main components.
An internal dispersed phase having a structure in which the g phase is dispersed inside the MR hydride phase exists in the form of islands dispersed in the base of the -TM-based alloy, and the lattice constant is a = 0.65 to 0.65. 0.85 nm, c =
A structure in which a phase having a tetragonal crystal structure of 0.90 to 1.10 nm and a composition ratio of (R + M) / T of 0.13 to 0.30 (hereinafter referred to as TE phase) is dispersed. A raw material alloy for producing a rare earth magnet powder, comprising: 3. The method according to claim 2, wherein the TE phase is dispersed so as to partially surround the internally dispersed phase having a structure in which the g phase is dispersed inside the MR hydride phase. 2
A raw material alloy for producing a rare earth magnet powder as described above. 4. The MR hydride phase according to claim 1, wherein M: 0.1-5.
4. The raw material alloy for producing a rare earth magnet powder according to claim 1, which is a hydride of R containing 0 atomic%. 5. The MR hydride phase, wherein M: 0.1 to 5
T containing 0 atomic% and not more than 30 atomic% (excluding 0)
4. The raw material alloy for producing a rare earth magnet powder according to claim 1, which is a hydride of R containing A and A. 6. The internally dispersed phase having a structure in which the g phase is dispersed inside the MR hydride phase has a spherical or nearly spherical shape (hereinafter, referred to as a spherical particle). The raw material alloy for producing a rare earth magnet powder according to claim 1, 2 or 3. 7. The internally dispersed phase having a structure in which the g phase is dispersed inside the MR hydride phase has a spindle shape, an ellipsoidal spherical shape, or a granular shape close to them (hereinafter, referred to as a spindle-shaped granular shape). A raw material alloy for producing a rare earth magnet powder according to claim 1, 2 or 3. 8. The rare earth magnet according to claim 1, wherein the internally dispersed phase having a structure in which the g phase is dispersed inside the MR hydride phase has a spherical shape and a spindle shape. Raw material alloy for powder production. 9. An RTM alloy ingot is heated to a predetermined temperature from room temperature to a temperature of less than 500 ° C. in a non-oxidizing atmosphere, or is heated and maintained, and then is mixed with hydrogen or hydrogen. In a mixed atmosphere of active gas, temperature: 5
The temperature is raised to and maintained at 00 to 750 ° C., and further, in a hydrogen or mixed atmosphere of hydrogen and an inert gas, at a temperature of 750 to 1000
C. The hydrogen ingot is subjected to a hydrogen occlusion treatment in which the RTM alloy ingot is occluded by raising the temperature to and maintained at a temperature of .degree. C. Subsequently, the RTM alloy ingot subjected to the hydrogen occlusion treatment is placed in an inert gas atmosphere. And performing a cooling treatment of cooling to room temperature in an inert gas atmosphere. 2. A method for producing a raw material alloy for producing a rare earth magnet powder, comprising the steps of: 10. An RTM-based alloy ingot is heated in a non-oxidizing atmosphere to a predetermined temperature from room temperature to a temperature of less than 500 ° C., or is heated and maintained, and then is mixed with hydrogen or hydrogen. Temperature: 7 in a mixed atmosphere of active gas
By raising the temperature to 50 to 1000 ° C. and holding it, the RT-
The M-based alloy ingot is subjected to a hydrogen storage treatment for absorbing hydrogen, and then the R-TM-based alloy ingot subjected to the hydrogen storage treatment is subjected to an inert gas heat treatment at 500 to 1000 ° C. in an inert gas atmosphere. And then subjecting the alloy to a cooling treatment for cooling to room temperature in an inert gas atmosphere. 11. The RTM-based alloy ingot,
The raw material alloy for producing a rare earth magnet powder according to claim 9 or 10, which is an RTM-based alloy ingot that has been homogenized by maintaining the temperature in a vacuum or Ar atmosphere at a temperature of 600 to 1200C. Manufacturing method. 12. The rare earth magnet powder according to claim 9, wherein the inert gas atmosphere in the inert gas heat treatment is an inert gas atmosphere within a pressure range of 0.5 to 11 atm. Production method of raw material alloy for production. 13. The cooling after the heat treatment with the inert gas is 5%.
00 ° C to 30 to 500 ° C / min. The method for producing a raw material alloy for producing a rare earth magnet powder according to claim 9, wherein the cooling is performed at a cooling rate of: