JPH11158587A - 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, the symbol M refers hereinafter to B or a component in which part of B is substituted by C, and the symbol A refers hereinafter to at least one element among Al, Ga, Si, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W, 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 integrally with a rim-like phase which surrounds the above internal dispersed phase and a part or the whole of which has an R2 T14 M-type tetragonal structure in the matrix of an R-T-M-A alloy composed essentially of R, T, M and A 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), B, or a component obtained by substituting a part of B with C (hereinafter referred to as M), Al, Ga, Si, Ti, V, C
Assuming that at least one of r, Zr, Nb, Mo, Hf, Ta, and W (hereinafter, indicated by A), R, T, M
And an alloy containing A as a main component (hereinafter referred to as an RTMA-based alloy), and a rare-earth magnet powder having a recrystallized texture with more excellent magnetic anisotropy can be obtained. It is also known.

[0004] However, if a hydrogen storage treatment is performed at a temperature in the range of 500 ° C to 1000 ° C and then a dehydrogenation treatment is performed in the temperature range, abnormal grain growth occurs because the treatment is always performed at a high temperature, and uniform and fine recrystallization is performed. In some cases, a texture cannot be obtained, and thus a rare-earth magnet powder having sufficient magnetic properties may not be obtained.

In order to solve this problem, Japanese Patent Application Laid-Open No. 9-310
As disclosed in Japanese Patent Application Publication No. 102-102, a phase consisting of a hydride of R containing M having an average particle size of 0.002 to 20 μm (hereinafter referred to as an MR hydride) is contained in a base of an RTMA-based alloy. Phase), and the MR hydride phase and the rim-like phase having a tetragonal structure of the R ₂ T ₁₄ M type partly or wholly surrounding the MR hydride phase are integrally dispersed in the form of islands. A method has been proposed in which a raw material alloy for producing a rare-earth magnet powder having the same structure as described above is prepared in advance, and the raw-material alloy for producing a rare-earth magnet powder is subjected to a dehydrogenation treatment to produce a rare-earth magnet powder. According to this method, since high-temperature heating is performed only for the time of the dehydrogenation treatment, there is an effect that long-lasting heating can be avoided, and thus abnormal growth of crystal grains can be avoided.

As shown in FIG. 5, the raw material alloy for producing a rare earth magnet powder disclosed in Japanese Patent Application Laid-Open No. Hei 9-310102 partially or partially surrounds an MR hydride phase having an average particle size of 0.002 to 20 μm. It has a structure in which a rim-like phase having an R ₂ T ₁₄ M-type tetragonal structure is entirely dispersed in the RTMA-based alloy base material in an island shape.

The MR hydride phase, when viewed three-dimensionally,
A spherical or nearly spherical granular hydride of R (hereinafter, referred to as spherical granular), a spindle-shaped or oval-shaped granular hydride of R (hereinafter, spindle-shaped granular), and a hydride of R. In some cases, spherical granules and spindle granules may coexist, and among them, the MR hydride phase is most preferably spindle granules, and the coexistence of spindle granules and spherical granules is more preferable. The shape is then preferred. Each of these MR hydrides is surrounded by a rim-like phase to form a composite phase.

[0008]

The problem to be solved by the present invention is disclosed in Japanese Patent Application Laid-Open No. 9-310.
No. 102, the raw material alloy for producing rare earth magnet powder,
When the dehydrogenation treatment is forcibly performed at a temperature of 500 to 1000 ° C., the magnetic anisotropy having a recrystallized texture of the R ₂ T ₁₄ M phase containing a uniform and fine A component in which grain growth is significantly suppressed is reduced. Excellent rare earth magnet powder can be obtained, and even if the above-mentioned dehydrogenation treatment is performed after storing the raw material alloy for a long period of time, the magnetic properties of the obtained magnet powder have almost no deterioration in magnetic properties. There has been a demand for a raw material alloy for producing rare earth magnet powder.

[0009]

Means for Solving the Problems Accordingly, the present inventors have
As a result of conducting research to obtain a raw material alloy for producing a rare earth magnet powder which is more excellent than the raw material alloy for producing a rare earth magnet powder described in JP-A-9-310102, (a) R-
Average particle size: 0.002 to 2 in the TMA alloy base
A phase in which a phase (hereinafter, referred to as a g phase) having a crystal structure that can be in a consistent relationship with the MR hydride is dispersed and present in the 0 μm MR hydride phase (hereinafter, the MR hydride phase). A phase in which the g phase is dispersed is referred to as an internally dispersed phase), and a rim-like phase having a tetragonal structure of the R ₂ T ₁₄ M type partially or wholly surrounds the internally dispersed phase. When a raw alloy for producing a rare earth magnet powder having a structure that is dispersed in an island shape is produced, and the raw alloy for producing a rare earth magnet powder is subjected to dehydrogenation treatment, a rare earth magnet powder having more excellent magnetic properties than before is obtained. You can get
(B) The raw material alloy for producing a rare earth magnet powder of (a) above,
Further, when the lattice constants are a = 0.65 to 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. It has been found that when a raw material alloy for producing a rare-earth magnet powder is subjected to a dehydrogenation treatment, a rare-earth magnet powder having more excellent magnetic properties than before can be obtained.

[0010] The present invention is based on the results of such research.
(1) a raw material of an RTMA-based alloy
Underground, MR hydrogenation with an average particle size of 0.002 to 20 μm
May be in a consistent relationship with the MR hydride inside the material phase
Dispersion of a structure in which g-phase having a crystalline structure is dispersed
Phase and some or all surrounding the internal dispersed phase
Is R_TwoT₁₄R-shaped phase having M-type tetragonal structure is integrated
Rare earth magnet powder having a structure dispersed in an island shape
Raw material alloy for production, (2) Underground of RTMA-based alloy
The g-phase is dispersed inside the MR hydride phase.
The internal dispersed phase and the part surrounding the internal dispersed phase or
Is all R _TwoT₁₄A rim-like phase having an M-type tetragonal structure
They are integrated and distributed in an island shape, and
Raw material for producing rare earth magnet powder having a phase dispersed structure
Alloy, (3) the TE phase is one of the MR hydride phases
Part around the internal dispersed phase in which the g phase is dispersed in the part
The rare earth magnet according to (2), which is dispersed in a surrounding state.
Material alloy for the production of stone powder.

[0011] 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. Also,
It is preferable that at least a part of the rim-like phase is a phase having a tetragonal structure of R ₂ T ₁₄ M type, but all of the rim-like phase is R ₂ T
_More preferably, the phase has a ₁₄ M-type tetragonal structure. The rim-like phase having a tetragonal structure of the R ₂ T ₁₄ M type partially contains A as a component and is partially hydride.

R is Nd, Pr, Dy, La, among at least one rare earth element among the rare earth elements including Y contained in the raw alloy for producing a rare earth magnet powder of the present invention.
Ce is particularly preferred, and A is Zr, Ga, Hf, N
Particularly preferred is at least one of b, Ta, Al and Si.

The structure of the raw material alloy for producing a rare earth magnet powder according to 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, the g phase is dispersed in the form of fine spots inside the MR hydride phase to form an internal dispersed phase, and the internal dispersed phase is dispersed in the form of islands in a matrix with the rim-shaped phase surrounded. It can be seen that there is a certain organization. FIG. 2 is a sketch of the structure of the raw material alloy for producing a rare earth magnet powder according to the above (2) and (3) of the present invention. From FIG. 2, it can be seen from FIG. 2 that the g phase is dispersed in the MR hydride phase in the form of fine spots to form an internally dispersed phase, and this internally dispersed phase is formed into an island shape in a matrix with the rim-like phase and the TE phase surrounded. It can be seen that it has a dispersed tissue. 1 and 2 is mainly composed of M (for example, Fe, Fe—Co, Fe ₂ B, (F
e, Co) ₂ B). The raw material alloy for manufacturing a rare earth magnet powder having the structure shown in FIGS. 1 and 2 is forcibly dehydrogenated by raising the temperature to a predetermined temperature in the range of 500 to 1000 ° C. in a vacuum atmosphere and maintaining the temperature. As a result, a rare-earth magnet powder having a fine R ₂ T ₁₄ M-type intermetallic compound phase and excellent in magnetic anisotropy having a recrystallized texture can be produced, and a tetragonal crystal of R ₂ T ₁₄ M containing A component can be produced. An excellent magnetic anisotropic magnet powder having a recrystallized texture in which the C-axis direction of the structure is aligned in a certain direction is obtained, and the rare earth magnet powder is bonded with an organic binder or a metal binder, or at a temperature of 600 to 600 ° C. Rare earth magnets can be manufactured by hot pressing or hot isostatic pressing at 900 ° C.

In order to produce the raw material alloy for producing a rare earth magnet powder of the above (1) of the present invention, an RTMA based alloy ingot, preferably an R-TMA alloy which has been homogenized at 900 to 1200 ° C. A TMA-based alloy ingot is prepared, and the ingot is heated from a room temperature to a predetermined temperature within a range of less than 500 ° C. in a non-oxidizing atmosphere (a vacuum atmosphere, an inert gas atmosphere, or the like). Or after heating and holding,
Temperature: 5 in an atmosphere of hydrogen or a mixture of hydrogen and an inert gas
Heated to a predetermined temperature in the range of 00 to 750 ° C. and held,
Further, in an atmosphere of hydrogen or a mixed atmosphere of 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 RTMA alloy ingot by keeping the temperature. The hydrogen-absorbing RTMA-based alloy ingot is subjected to an inert gas heat treatment at 500 to 1000 ° C. in an inert gas atmosphere. It can be manufactured by performing a cooling process of cooling to room temperature in an atmosphere.

Further, in order to produce the raw material alloy for producing a rare earth magnet powder according to the above (2) or (3) having a structure in which the TE phase is dispersed according to the present invention, an RTMA-based alloy ingot is required. Preferably, an RTMA-based alloy ingot that has been subjected to a homogenization treatment at 900 to 1200 ° C. is prepared, and this ingot is heated from room temperature in a non-oxidizing atmosphere (vacuum atmosphere, inert gas atmosphere, etc.). Temperature: After raising the temperature to a predetermined temperature within a range of less than 500 ° C., or after maintaining the temperature,
Temperature: 7 in an atmosphere of hydrogen or a mixture of hydrogen and an inert gas
The R-T-MA-based alloy ingot is subjected to a hydrogen-absorbing treatment by raising the temperature to a predetermined temperature in the range of 50 to 1000 ° C. and holding the same, and subsequently, the R which has been subjected to this hydrogen-absorbing treatment is treated. -TMA-based alloy ingot is subjected to an inert gas heat treatment at a predetermined temperature in the range of 500 to 1000 ° C. in an inert gas atmosphere.
It can be manufactured by performing a cooling process of cooling to room temperature in an inert gas atmosphere.

Accordingly, the present invention provides (4) RTM-
The A-based alloy ingot is heated in a non-oxidizing atmosphere from room temperature to a predetermined temperature within a range of less than 500 ° C., or is heated and maintained, and then is heated in hydrogen or a mixed atmosphere of hydrogen and an inert gas. Temperature: The temperature is raised to a predetermined temperature in the range of 500 to 750 ° C. and maintained, and further raised to a predetermined temperature in the range of 750 to 1000 ° C. in hydrogen or a mixed atmosphere of hydrogen and an inert gas. By holding, RT-M-
R-T-M-A which has been subjected to a hydrogen storage process for storing hydrogen in an A-based alloy ingot, and subsequently subjected to a hydrogen storage process.
500 to 10-10 in an inert gas atmosphere
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 00 ° C. and then subjected to a cooling treatment of cooling to room temperature in an inert gas atmosphere; (5) RT-
The MA 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 heated in a hydrogen or a mixed atmosphere of hydrogen and an inert gas. Temperature: A hydrogen storage treatment is performed to raise and maintain a predetermined temperature in the range of 750 to 1000 ° C. to store hydrogen in the RTMA alloy ingot,
Subsequently, the RTMA-based alloy ingot that has been subjected to the hydrogen storage treatment is heated in an inert gas atmosphere at a temperature of 500 to 10
(6) a method for producing a raw alloy for producing a rare earth magnet powder, which comprises performing an inert gas heat treatment at a predetermined temperature within a range of 00 ° C., and then performing a cooling process of cooling to room temperature in an inert gas atmosphere; In the method for producing a raw material alloy for producing a rare earth magnet powder, the RTMA-based alloy ingot is heated in a vacuum or Ar atmosphere at a temperature of 600 to 1200.
RTMA that has been homogenized by holding at
The method according to the above (4) or (5), which is a raw alloy for producing a rare earth magnet powder, which is a system alloy ingot.

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 the atmosphere is a combination 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 adsorbed gas from 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, the RTMA alloy is heated or kept at a predetermined temperature within a range of less than 500 ° C. from room temperature in a non-oxidizing atmosphere, and then heated to a hydrogen gas atmosphere or hydrogen. Temperature: 5 in a mixed gas atmosphere of gas and inert gas
Heated to a predetermined temperature in the range of 00 to 750 ° C. and held,
Further, hydrogen is absorbed in the RTMA alloy by raising the temperature to a predetermined temperature within the range of 750 to 1000 ° C. and maintaining the temperature in a hydrogen gas atmosphere or a mixed gas atmosphere of hydrogen gas and an inert gas. The RTMA-based alloy ingot, which has been subjected to a phase transformation and subsequently subjected to a hydrogen storage treatment, is maintained at a predetermined temperature within a range of 500 to 1000 ° C. in an inert gas atmosphere. This indicates that a gas heat treatment is performed, and then cooling to room temperature is performed 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, the RTMA-based alloy is heated or kept at a predetermined temperature within a range of less than 500 ° C. from room temperature in a non-oxidizing atmosphere, and then heated in a hydrogen gas atmosphere or a hydrogen gas atmosphere. In a mixed gas atmosphere of a gas and an inert gas, the temperature is raised to and maintained at a predetermined temperature in the range of 750 to 1000 ° C., whereby hydrogen is absorbed in the RTMA alloy so that the phase transformation is performed. And then subjecting the RTMA-based alloy ingot subjected to the hydrogen storage treatment to an inert gas heat treatment at a predetermined temperature in the range of 500 to 1000 ° C. in an inert gas atmosphere, Next, it is shown that cooling is performed 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 a method for producing a material alloy for producing a rare earth magnet powder (5) according to the present invention. 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 according to the present invention, the hydrogen-absorbing RTMA alloy is treated with an inert gas atmosphere (pressure) such as Ar gas or He gas. : 0.5 to 11 atm, preferably pressure: 1.2 to 11 atm, more preferably 1.
Temperature: 500 to 1 in an inert gas atmosphere of 2 to 2 atm)
At a predetermined temperature in the range of 000 ° C. (preferably 650 to 950 ° C., more preferably 750 to 900 ° C.) for 30 seconds to 5 hours (preferably 1 minute to 1 hour, more preferably 10 minutes to 30 minutes). This is a heat treatment that is maintained for a predetermined time within the range. This inert gas heat treatment has a pressure of 1.2 to 2 at.
It is most preferable that the temperature is maintained at 750 to 900 ° C. for 1 to 30 minutes in an Ar gas atmosphere of m.
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 is performed to room temperature 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.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Example 1 An RF-M-A-based alloy a having the component composition shown in Table 1 was melted by using a high-frequency vacuum melting furnace, and the obtained molten metal was cast.
To RT-MA-based alloys a to j
A square block of 10 mm or less is produced from the ingot of the above, and this block is placed in a vacuum atmosphere of 1 × 10 ⁻³ Torr or less.
The homogenization treatment was performed at a temperature of 1130 ° C. for 30 hours.

[0028]

[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.

[0030]

[Table 2]

[0031]

[Table 3]

[0032]

[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 inside an MR hydride phase composed of a hydride of R 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.

[0035]

[Table 5]

[0036]

[Table 6]

[0037]

[Table 7]

Example 2 The R-T- component having the composition shown in Table 1 prepared in Example 1 was used.
After subjecting the blocks of the MA-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 the pressures shown in Tables 8 to 10 ,
A hydrogen storage treatment was performed under the holding temperature conditions shown in Tables 8 to 10, followed by an inert gas heat treatment under the conditions shown in Tables 8 to 10, and then with Ar gas under the conditions shown in Tables 8 to 10. Forcibly cool to room temperature,
60 were produced.

[0039]

[Table 8]

[0040]

[Table 9]

[0041]

[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.

Further, the raw materials 31 to 60 of the present invention were placed in the atmosphere,
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.

[0044]

[Table 11]

[0045]

[Table 12]

[0046]

[Table 13]

Conventional Example 1 R-T- having the component composition shown in Table 1 prepared in Example 1
Table 14 shows the homogenized blocks of MA alloys a to j.
Are processed in a hydrogen atmosphere and an inert gas atmosphere under the conditions shown in (1) to (3) to produce the conventional raw materials 1 to 10. The structures of the conventional raw materials 1 to 10 are observed with a transmission electron microscope, and the inside of the MR hydride phase is G phase and T dispersed in
The presence or absence of the E phase was examined, and the results are shown in Table 15.

Further, the conventional raw materials 1 to 10 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 Table 15.

[0049]

[Table 14]

[0050]

[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 to 200 μm or less show the existence of the g layer and the TE phase produced by the conventional method using the same alloy a in Table 1. It can be seen that the magnetic properties of the rare earth magnet powder obtained by subjecting the conventional raw material 1 to a dehydrogenation treatment, quenching, and pulverizing the raw material 1 to 200 μm or less are excellent.

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 00 μm were obtained by using the same alloys b to j in Table 1 and dehydrogenating the g layer manufactured by the conventional method and the conventional raw material having no TE phase. It can be seen that the magnetic properties of the rare earth magnet powder obtained by treating, quenching, and grinding to 200 μm or less are superior.

[0053]

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 different from those of the conventional g phase and the TE phase. Which is superior to the magnetic properties of rare earth magnet powders obtained by dehydrogenation of raw material alloys with no iron, can provide rare earth magnet powders superior to conventional ones, and has excellent industrial effects It is.

[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.

FIG. 5 is a structural sketch of a conventional raw material alloy for producing rare earth magnet powder.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // B22F 9/00 H01F 1/04 H (72) Inventor Noriyuki Oki 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Kyushu University Science and Engineering Graduate School (72) Inventor Noriyuki Kuwano 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Graduate School of Comprehensive Science and Engineering, Kyushu University (72) Inventor Ken Itakura 6-1 Kasuga Park, Kasuga City, Fukuoka Prefecture Graduate School of Comprehensive Science and Engineering, Kyushu University

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
), Al, Ga, Si, Ti, V, Cr, Zr, Nb, M
o, Hf, Ta, and W (hereinafter, A
) And an alloy containing as a main component (hereinafter, this alloy is referred to as R
-T-M-A-based alloy), a phase comprising an R hydride containing M having an average particle size of 0.002 to 20 μm (hereinafter referred to as an MR hydride phase) A phase having a structure in which a phase having a crystal structure (hereinafter, referred to as a g phase) that can be in a consistent relationship with the MR hydride is dispersed (hereinafter, this phase is referred to as an internal dispersed phase), and a periphery of the internal dispersed phase; Part or all of R ₂ T ₁₄ M
A raw material alloy for producing a rare earth magnet powder, wherein the raw material alloy has a structure in which a rim-like phase having a tetragonal structure of a mold is integrated and dispersed in an island shape. 2. A g-phase is dispersed inside an MR hydride phase in a base of an RTMA-based alloy having a composition containing R, T, M, and A as main components. An internal dispersed phase having a constitution and a rim-like phase having a tetragonal structure of the R ₂ T ₁₄ M type in which a part or the whole surrounding the internal dispersed phase is present in an integrated and dispersed island form; The lattice constants are a = 0.65 to 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. The RTMA-based 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 to and maintained at a predetermined temperature. In a mixed atmosphere of inert gas and inert 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 storage treatment is carried out in which the RTMA-based alloy ingot absorbs hydrogen by raising the temperature to ℃ and holding it, and then the RTMA-based alloy ingot which has been subjected to the hydrogen storage treatment is subjected to the hydrogen absorption treatment. 500-1000 ° C in an active gas atmosphere
A method for producing a raw material alloy for producing a rare earth magnet powder, comprising: performing a holding inert gas heat treatment; and performing a cooling process of cooling to room temperature in an inert gas atmosphere. 10. An RTMA-based 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 heated to and maintained at a predetermined temperature. Temperature: 7 in a mixed atmosphere of inert gas and inert gas
By raising the temperature to 50 to 1000 ° C. and holding it, the RT-
The MA-based alloy ingot is subjected to a hydrogen-absorbing treatment for absorbing hydrogen, and then the RT-MA-based alloy ingot subjected to the hydrogen-absorbing treatment is subjected to an inert gas atmosphere at 500 to 1000 ° C.
A method for producing a raw material alloy for producing a rare earth magnet powder, comprising: performing a holding inert gas heat treatment; and performing a cooling process of cooling to room temperature in an inert gas atmosphere. 11. The RTMA-based alloy ingot is prepared in a vacuum or Ar atmosphere at a temperature of 600 to 1200.
RTMA that has been homogenized by holding at
The method for producing a raw material alloy for producing a rare earth magnet powder according to claim 9 or 10, wherein the method is a system alloy ingot. 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: