JP2003193208A - Magnet material and production method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a magnet which contains hyperfine crystal grains, and has a high residual magnetic flux density, and a sufficient maximum magnetic energy product. <P>SOLUTION: The magnet material is substantially expressed by the general formula of R<SB>x</SB>(T<SB>1-u-v-w</SB>Cu<SB>u</SB>M1<SB>v</SB>M2<SB>w</SB>)<SB>1-x-y</SB>A<SB>y</SB>(wherein, R is at least one kind of element selected from rare earth elements inclusive of Y; T is Fe or Co; M1 is at least one kind of element selected from Zr, Ti, Nb, Mo, Ta, W, and Hf; M2 is at least one kind of element selected from Cr, V, Mn, and Ni; A is at least one kind of element selected from N and B; and x, y, u, v, and w are atomic ratios, respectively, and satisfy 0.04≤x≤0.2, 0.001≤y≤0.2, 002≤u≤0.2, 0≤v≤0.2, and 0≤w≤0.2), and contains a 0.2 to 10 vol.% non- magnetic phase containing ≥20 atomic % Cu, and a hard magnetic main phase, and in which the mean crystal grain size of the hard magnetic main phase is ≤100 nm. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a magnet material and a method for manufacturing the same.

[0002]

2. Description of the Related Art Sm-Co magnets, Nd-Fe-B magnets and the like are known as high-performance rare earth magnets, and they are currently mass-produced. Such high-performance magnets are mainly motors,
It is used in electrical equipment such as speakers and measuring instruments. In recent years, there has been an increasing demand for reduction in size and weight of various electric devices and reduction in power consumption, and in order to meet these demands, higher performance permanent magnets having improved maximum magnetic energy products (BHmax) of permanent magnets have been demanded. There is. As a candidate for new high-performance magnet material, Sm-Fe-N-based material was Coey in 1990.
It has been announced and is attracting attention. Sm-Fe-N
Has a high saturation magnetization and Nd-Fe comparable to Nd-Fe-B.
Since it has a large magnetic anisotropy exceeding -B, it is expected to be applied as a high-performance magnet.

R-TN system permanent magnet material (R is one or more rare earth elements, T is Fe or Fe and Co)
In order to realize high magnetic properties, it is necessary to optimize the nitriding treatment conditions, and it is important to refine the crystal grains. Coercive force (iHc) can be increased by refining the crystal, and exchange coupling works between fine particles to improve residual magnetic flux density (Br) and maximum magnetic energy product (BH) max. As the refining means, the molten metal quenching method, hydrogenation
There is a method of refining crystals by a decomposition reaction / dehydrogenation / recombination reaction treatment (HDDR method). In order to obtain a fine and uniform alloy structure, the melt quenching method requires a fast melt quenching rate and a highly accurate quenching control technique, which increases equipment costs.
It leaves production challenges. On the other hand, the HDDR method is a versatile, low-cost manufacturing method.

Attempts to develop high performance SmFeN by the HDDR method have been made by several research groups after the presentation of Coey et al. Chen
And Z. Altounian is F in Sm ₂ Fe ₁₇
Part of e is various elements (Ti, V, Cr, Zr, Nb, M
o, Hf, Ta, W) and the HDDR reaction behavior was investigated in detail, and it was found that high magnetic properties were obtained when substituted with Ti or Nb (Journal of
Applied Physics, 75 (10) (1
991) p6012). In addition, Toyoyo et al. Sm ₂ Fe ₁₇
It has been reported that Ti and B can be added to Si to reduce the average grain size to 200 nm (Proceeding
s of 16 ^th International W
orkshop on RE Magnets and
Their Applications (2000)
p793). However, this method cannot be said to be sufficient in refining the crystal grains, and the residual magnetic flux density (Br) is small, the coercive force (iHc), and the maximum magnetic energy product are smaller than those obtained by the melt quenching method. (BH) m
There is a problem that ax is insufficient. In addition, HDDR
Development of high-performance NdFeB by the method
It has been found that anisotropic alloy powder can be obtained by adjusting the alloy composition or optimizing the treatment process (Jour.
nal of Magnetic Society o
f Japan, 23 (1999) p300), the average grain size of the crystal grains is 300 nm, and further finer structure and higher characteristics are required.

[0005]

As described above, in the conventional magnet, the residual magnetic flux density (Br) is insufficient due to insufficient refinement of the crystal grains, resulting in insufficient magnetism. There was a problem that the maximum magnetic energy product (BH) max was not obtained. The present invention has been made to address such a problem, and an object thereof is to provide a magnet material and a manufacturing method having an ultrafine crystal body of 100 nm or less that can realize high magnetic characteristics.

[0006]

The present invention has the above-mentioned objects.
To achieve ultrafine grain of magnet material to achieve
It was made as a result of repeated studies. You
That is, the first invention is represented by the general formula R_x(T
_1-uv-wCu_uM1_vM2 _w)_1-xyA_y
(In the formula, R is at least selected from rare earth elements including Y.
Also, one element, T is less than Fe or Co
Both are one element, M1 is Zr, Ti, Nb, Mo, T
at least one element selected from a, W, and Hf, M2
Is at least one selected from Cr, V, Mn, and Ni.
Element, A is at least one element selected from N or B
Element, x, y, u, v are each in atomic ratio 0.04 ≦ x ≦
0.2, 0.001 ≦ y ≦ 0.2, 0.002 ≦ u ≦
0.2, 0 ≦ v ≦ 0.2, 0 ≦ w ≦ 0.2)
And a non-magnetic phase containing Cu of 20 atomic% or more 0.2 to
10% by volume and a hard magnetic main phase, and
Characterized in that the average crystal grain size is 100 nm or less
It is a magnetic material.

In the first aspect of the present invention, the crystal structure of the hard magnetic main phase is TbCu ₇ type, Th ₂ Ni ₁₇ type, T
The h ₂ Zn ₁₇ type and the Nd ₂ Fe ₁₄ B type are desirable. In addition, ThMn ₁₂ type, RE ₃ T
It does not matter if the _29- type phases are mixed. Further, it is desirable that M1 always contains at least one element selected from Ti, Zr, Nb, Hf or Mo, and further, M2 always contains at least one element selected from Cr or V. Is desirable.

Further, in the second aspect of the present invention, the raw material powder is pulverized to an average powder particle size of 3 to 500 μm, and then 0.1 to 1
The hydrogenation and decomposition reaction treatment is carried out by holding at 450 to 850 ° C. for 1 to 8 hours in 0 atm of hydrogen gas or an inert gas having a hydrogen gas partial pressure other than nitrogen gas, and then 1
0.1 at 600 ° C to 950 ° C in a vacuum of 3.3 Pa or less
The method for producing a magnet material is characterized by including a step of carrying out dehydrogenation and recombination reaction treatment by holding for ~ 3 hours.

(Function) The present inventors have made R-T-M-Cu
As a result of research on the alloy system, the coexistence relationship between the RT phase having a high T concentration and the nonmagnetic Cu-rich phase was found in the RT-M-Cu system, and a patent application has already been made (Japanese Patent Laid-Open No. 2001-2001). 1
98206), the present invention has led to the invention from these research processes. It is possible to form an ultra-fine crystal using the HDDR method by introducing a non-magnetic phase Cu-rich phase. Further, from the viewpoint of the crystal structure stability of the RTA alloy system, at least one of two kinds of M1 and M2 is used.
As a result of studying the effect of further adding multiple elements of the species,
The present invention has been completed.

That is, the magnet material of the present invention is R-T-
It is characterized in that Cu element is added to introduce a Cu-rich phase based on the A type. Up to now, there have been some reports on a technique for improving the magnetic characteristics by substituting an atom such as Cu for part of the T. For example, JP-A-11-293418 and JP-A-11-29
Japanese Patent No. 7518 discloses that Cu is added to the M element group of the SmFeMN magnet material, but in this technique, the main phase or the main phase + soft magnetic phase structure is ideal for the alloy structure. 20 atom%
There is no disclosure regarding the existence of the nonmagnetic phase (Cu-rich phase) containing Cu. That is, there was no idea of forming a Cu-rich phase. The present invention has been completed with the idea that the introduction of the Cu-rich phase makes it possible to make the crystal grains ultrafine as compared with the case where it does not exist. Furthermore, the present invention has a strong influence on the crystal structure of the R-Fe-A based alloy in addition to the presence of the Cu-rich phase described above.
The characteristics can be further improved by adding at least one of two kinds of elements (M1 element which is hard to form a solid solution with Fe and M2 element which is easy to form a solid solution with Fe).
This is because the presence of a Cu-rich phase and the addition of at least one of these two types of elements improve the nucleation rate of each reaction during the HDDR process and suppress grain growth.
It is possible to achieve a further ultrafine alloy structure and high magnetic properties. It is particularly desirable to add at least three kinds of Cu-rich phase, M1 element and M2 element in combination.

Further, in the invention of this manufacturing method, H
For the DDR processing, mainly hydrogenation / cracking reaction (HD reaction:
Coarse main phase-> T phase + R hydride) and dehydrogenation / recombination reaction (DR reaction: T phase + R hydride-> fine main phase) occur complicated reactions, and ultrafine and uniform The control of the HD reaction and the DR reaction is extremely important for obtaining crystal grains. In the present invention, the atmosphere type and partial pressure during HDDR treatment,
By controlling the processing temperature and time, it becomes possible to make the crystal grains ultrafine.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Modes for carrying out the present invention will be described below. Magnet materials of the present invention have the general formula R _x as described above _{(T 1-u-v-} w Cu u M1 v M2 w)
During _{1-x-y A} y (wherein, at least one element R selected from rare earth elements including Y, T is at least one element selected from Fe or Co, M1 is Zr, Ti, Nb, Mo , T
at least one element selected from a, W, and Hf, M2
Is at least one element selected from Cr, V, Mn, and Ni, A is at least one element selected from N or B, and x, y, u, and v are each an atomic ratio of 0.04 ≦ x ≦.
0.2, 0.001 ≦ y ≦ 0.2, 0.002 ≦ u ≦
0.2, 0 ≤ v ≤ 0.2, 0 ≤ w ≤ 0.2), and a non-magnetic phase containing Cu of 20 atomic% or more 0.2 to
10% by volume and a hard magnetic main phase are included, and the average crystal grain size of the hard magnetic main phase is 100 nm or less.

Each component constituting the magnet material of the present invention will be described in detail below. (1) R element As the R element, at least one element selected from rare earth elements including Y is used. Each of the R elements brings about a large magnetic anisotropy to the magnet material and is added in a range of 4 to 20 atomic% in order to impart a high coercive force. If the total amount of R elements is less than 4 atom%, a large amount of α-Fe precipitates and a large coercive force cannot be obtained, while if it exceeds 20 atom%, a large amount of R rich phase is formed and the saturation magnetization is significantly lowered. . The more preferable compounding amount of the R element is 8 to 12 atom% when the A element is mainly N, and more preferably 8.5.
Is about 11 atomic%, and when the A element is mainly B, 8
To 14 atom%, and more preferably 11 to 12.5.
It is atomic%. As the R element, Sm, Nd, and Pr are preferably used, and Sm and Nd are particularly preferable. When N is mainly used as the A element, 50 atomic% or more of the total amount of R,
More preferably, Sm of 70 atom% or more is effective for enhancing the performance of the magnet material, especially the coercive force.

(2) T Element The T element is at least one element selected from Fe or Co, and mainly plays a role in magnetizing the magnet material. The saturation magnetization of the magnet material can be increased by adding a large amount of T, but if it is added excessively, the coercive force may be lowered due to the precipitation of the α-Fe phase.

(3) Cu Cu is an effective element for refining the alloy structure. Addition of an appropriate amount of Cu not only improves the nucleation rate during the HDDR reaction, but also Cu-rich alloy phase (Cu content of 20 atomic%
The above is formed, and it is extremely effective as a pinning site for grain growth inhibition to suppress grain growth during HDDR treatment.
It has the effect of making the tissue ultrafine. Since the main constituent elements of the Cu-rich phase in the alloy are Cu and R, in order to form the Cu-rich phase, in addition to adding the Cu element in the Cu solid solution region or more in the main phase, It is important to increase the addition amount of the R element depending on the amount. If T in the mere composition is replaced with Cu without adjusting the amount of R element in the alloy composition, a coarse soft magnetic T phase may be formed in the mother alloy, and the coercive force may be significantly reduced. The Cu-rich alloy phase acts as a pinning site, and is also extremely effective in reducing the HDDR temperature of the RTA alloy. In particular, when M1 and M2 elements are added to increase the HDDR reaction temperature of the alloy, C
By the combined addition with u, the HDDR reaction can be completed at a lower temperature and / or a shorter time, and it is effective for the refinement of crystal grains. If the compounding amount of Cu is less than 0.2 atom% of the total amount of T, M1, M2, Cu, the compounding effect cannot be sufficiently achieved, while if it exceeds 20 atom% of the total amount of T, M1, M2, Cu. This causes a decrease in saturation magnetization. A more preferable amount of Cu element is 0.5 to 10 of the total amount of T, M1, M2 and Cu.
Atomic%, more preferably 1 to 7 atomic%.
50 atomic% or less of Cu is Si, Ga, Zn, A
It can be substituted with at least one element selected from l and Ge. With such a composition, the squareness of the demagnetization curve may be improved, and the magnet characteristic may be improved.

(4) M1 element The M1 element is at least one element selected from Zr, Ti, Nb, Mo, Ta, W and Hf.
It has a strong influence on the crystal structure of the A-based alloy, suppresses the grain growth of the main phase during the DR recombination reaction, and is effective for refining the alloy structure. In addition, it is also effective for suppressing the precipitation of α-Fe phase in the master alloy. However, substitution of the M1 element may increase the HD reaction temperature of the alloy, and the effect of refining only the M1 element is insufficient. The composite addition of the Cu-rich phase and the M1 element has a higher effect of miniaturization than the addition of only the Cu-rich phase or the addition of the M1 element alone. The M1 element mainly substitutes the site occupied by the T element in the main phase, but when the compounding amount of M1 exceeds 20 atomic% of the total amount of T, M1, M2 and Cu, the saturation magnetization is significantly lowered. A more preferable compounding amount of the M1 element is 1 to 10 atom% of the total amount of T, M1, M2 and Cu, and further preferably 1.5 to 8 atom%. M1
As elements, Ti, Zr, Nb, Hf and Mo are preferably used, Ti, Zr and Nb are particularly preferable, and a combination of Ti + Zr is particularly preferable.

(5) M2 element The M2 element is at least one element selected from Cr, V, Mn, and Ni. In addition to determining the crystal structure of the R-Fe-A system alloy, refining the alloy structure. Is effective for. In particular, unlike the Cu and M1 elements, the M2 element is likely to form a solid solution with Fe, so a large amount is also present in the α-Fe phase after the HD decomposition reaction, and the DR recombination reaction (T phase + R hydride-> fine) It is important for the refinement of the structure by promoting the nucleation of the main phase at the time. However, the effect of refining only the M2 element is insufficient, and the composite addition with the Cu phase, particularly the ternary composite addition of the Cu phase and the M1 element is extremely effective for the ultra-fine structure. M
The two elements mainly substitute the sites occupied by the T element in the main phase, but when the compounding amount of M2 exceeds 20 atomic% of the total amount of T, M1, M2 and Cu, the saturation magnetization is significantly lowered. A more preferable compounding amount of D element is 1 to 10 atomic% of the total amount of T, M1, M2 and Cu, and further preferably 1.5 to 8
It is atomic%. It is preferable to use Cr and V as the M2 element.

(6) A element Element A mainly exists in the interstitial position of the main phase
Existing, and the crystal lattice is expanded compared to the case where A element is not included.
Curie by changing or changing the electronic structure
Functions to improve temperature, magnetic anisotropy, and saturation magnetization
It When B is mainly used as the A element, the crystal structure of the main phase is N
d_TwoFe₁₄When it is B type and N is mainly used as the A element
Has a main phase crystal structure of TbCu₇Type, Th_TwoNi₁₇Type,
Th_TwoZn ₁₇It is one of the types. The blending amount of A element
If it is less than 0.1 atom%, the compounding effect can be sufficiently achieved.
On the other hand, if it exceeds 20 atom%, the saturation magnetization will decrease.
Ku. A more preferable blending amount of element A is mainly when B is used.
4 to 10 atom%, when N is mainly used, 3 to 18 raw
% Child. 50 atomic% or less of the element A is H, C,
Substitute with at least one element selected from S, P and O
You can In this case, H, C, S, P,
By replacing O or adding N and B in combination, the mother alloy or HD
A fine hydrogen compound phase, B
Form a H-phase, C-rich phase, etc. to further refine the structure
And so on. Even if N is mainly used as the A element
It is preferable to use B. Compounding amount of each element and manufacturing professional
Depending on the process, TbCu₇Mold, Nd_TwoFe₁₄B type,
Th_TwoNi₁₇Type, Th_TwoZn₁₇Mold, ThMn
₁₂Phase, R_ThreeFe₂₉Phase may be the main phase
But TbCu₇Type, Nd_TwoFe₁₄Mainly one of B type
Particularly high magnetic properties can be obtained when the phases are used. here
In the above, the main phase means each crystal phase and non-crystal phase constituting the magnet material.
Means the phase with the highest volume occupancy of the crystalline phases
It is a thing. The magnetic material of the present invention has a T content of 50 atomic% or more.
The soft magnetic phase may be included in an amount of 0.5 to 40% by volume.
It In this case, the coercive force is lowered to some extent, but high B
r is obtained. The average grain size and the volume ratio of alloy phase are
Observation by electron microscope or optical microscope, X-ray diffraction, etc.
It is judged comprehensively based on the
It can be determined by the area analysis method of a scanning electron micrograph.
Wear. The magnetic material of the present invention contains inevitable impurities such as oxides.
Is allowed to be included.

(Manufacturing Method) Next, an example of a method for manufacturing the magnet material according to the present invention will be described. First, a certain amount of R,
Coarse alloy powder containing T, M1, M2, Cu and A elements is prepared. When the element A is mainly N, a gas treatment is used after the HDDR treatment to contain nitrogen. Coarse alloy powder can be obtained by crushing a master alloy obtained by arc melting, high frequency melting, or the like to an average powder particle size of 3 to 500 μm.
By setting the average powder particle size of this master alloy in this range, the effect of obtaining a uniform fine structure and good squareness after HDDR is exhibited. It can also be obtained by crushing an alloy ribbon produced by the strip casting method. The alloy powder thus obtained or the alloy before pulverization can be heat-treated as necessary to homogenize it. It is also possible to control the type and volume occupancy of the main phase by adjusting the alloy powder and the heat treatment conditions. A preferable master alloy structure includes an RTMD-Cu-A hard magnetic phase and a volume ratio of 0.1 to 10% Cu-rich phase (R-Cu phase). Also, the use of alloy ribbon produced by the strip casting method leads to a sharp particle size distribution of the powder, so the HDD
A more uniform ultrafine structure is obtained through the R treatment, and a more uniform nitrogen treatment and higher magnetic properties are obtained.

Next, the HDDR conditions suitable for the present invention will be explained.
To do. Hydrogenation / decomposition reaction treatment (HD treatment) is 0.1 to 1
Inactive in hydrogen gas of 0 atm or with hydrogen gas partial pressure
450 ~ 950 ℃, 1 ~ in natural gas (excluding nitrogen gas)
Hold for 8 hours. In the HD process, hydrogenation and decomposition reactions
Therefore, the hard magnetic phase, which is the main phase in the master alloy, is R hydride.
And T, T-M1-M2, T-M1-M2-Cu, Cu
HD processing is completed before decomposition and R hydride coarsening
Is preferred to obtain a fine structure and good magnetic properties
Yes. If the HD process is colder and / or shorter
No decomposition reaction at all, or part of the master alloy
Only the decomposition reaction occurs. In this case, the decomposition reaction
Since the crystal grains do not become finer in the part that did not come up, post treatment
DR process, nitriding treatment (when A element is mainly N)
Of the nitrided magnet powder obtained through
H) max is low. On the other hand, the HD process is
/ Or the structure after HD treatment becomes coarser on the long side,
Therefore, DR treatment and nitriding treatment (when the A element is mainly N)
The magnetic properties are poor because the subsequent hard magnetic phase becomes coarse.
Turn into. The preferred HD treatment condition is the crystal structure of the alloy main phase.
Depends, but Nd_TwoFe ₁₄600 for B structure
850 ° C, 2 to 4 hours, other than 500 to 7
50 ° C., 2 to 4 hours. It should be noted that HD processing is multistage
It is also effective for ultra-fine structure. This temperature range and
And heating time within this range
Sufficient nuclei are generated during the reaction to suppress abnormal grain growth,
After the treatment, an ultrafine (R hydrate + T phase) structure is obtained.

Dehydrogenation / recombination reaction treatment (DR treatment) is 1
0.1 at 650 ° C to 950 ° C in a vacuum of 3.3 Pa or less.
Hold for ~ 2 hours. In the DR process, dehydrogenation / reconstitution
The R hydride disappears due to the combination reaction, and TbCu₇Mold, Nd
_TwoFe₁₄B type, Th_TwoNi ₁₇Type, Th_TwoZn
₁₇Mold, ThMn₁₂Phase, R_ThreeFe₂₉One of the phases
Recrystallizes into a phase with a crystal structure, but the recrystallized grains become coarse
It is possible to obtain good magnetic properties by finishing the DR process before
Preferred for DR process is colder and / or shorter
On the time side, no recombination reaction occurs, or
The recombination reaction occurs only in part. In this case, rejoin
The T phase, which is a soft magnetic phase, remains in the area where the reaction did not occur.
Nitriding treatment (when the A element is mainly N,
IHc of the magnet powder obtained through the above (3) is low. On the other hand, D
If the R process is at a higher temperature side and / or a longer time side, DR treatment is performed.
After the treatment, the structure becomes coarse-grained, and therefore DR treatment and nitriding treatment
(Only when the A element is mainly N)
The magnetic properties deteriorate due to the increase in size. Preferred HD treatment strip
The condition depends on the crystal structure of the alloy main phase, but Nd_TwoFe₁₄
In the case of B structure, in a vacuum of 13.3 Pa or less, 700 to
950 ° C., 0.2 to 1 hour, and other than that, 13.
650 ° C to 900 ° C, 0.2 to 1 in a vacuum of 3 Pa or less
It's time. Set this temperature range and heating time to this range.
The main phase nuclei during the dehydrogenation / recombination reaction by
Is generated, and abnormal grain growth is suppressed.
The organization is obtained.

When the A element is mainly N, then N is added to the alloy powder. In this case, 0.1
It is desirable to perform heat treatment at a temperature of 300 to 900 ° C. for 0.1 to 100 hours in a nitrogen gas atmosphere of ˜100 atm. As the atmosphere of the heat treatment, a nitrogen compound gas such as ammonia may be used instead of nitrogen gas. It is also possible to control the nitriding reaction by using a mixture of nitrogen gas or nitrogen compound gas and hydrogen gas. It is possible to replace a part of N with H by using a nitrogen compound gas such as ammonia or by mixing hydrogen gas. The magnetic material of the present invention can be used as a bonded magnet. Epoxy type or nylon type resin is usually used as a binder, but it is also possible to manufacture a metal bond magnet using a low melting point metal or a low melting point alloy as a binder. It is also possible to manufacture a magnet by integrating the magnet material of the present invention into a high-density compact by hot pressing, hot isostatic pressing, spark plasma sintering, or the like. In the manufacture of a magnet using the magnet material of the present invention, it is desirable not to raise the temperature to 800 ° C or higher.

[0023]

EXAMPLES Next, specific examples of the present invention will be described.
To do. (Examples 1 to 36) First, the high-purity raw materials are shown in Table 1.
Mix in a predetermined ratio, melt by high frequency in Ar atmosphere
Make alloy ingot and use mortar to average powder particle size 3
It was crushed to a size of 00 μm or less. Continue to add 1 part of this alloy powder
1 ~ 8 hours at 500 ~ 800 ℃ in hydrogen gas above atm
Hydrogenation and cracking reaction treatment is carried out for 1 hour, then 1
0.1 at 650 ° C to 900 ° C in a vacuum of 3.3 Pa or less
Performed dehydrogenation / recombination reaction treatment for ~ 2 hours
Then, in a nitrogen gas atmosphere of 1 atm, at a temperature of 450 ° C. for 10 minutes.
Heat treatment was performed for an hour to produce magnet powder. Of each processing stage
The generation phase of each alloy powder was analyzed by X-ray diffraction analysis and TEM / EDS.
After the HD treatment, it was found that Sm hydride and α-F
It becomes the e phase, and after the DR treatment it is mainly the uniform and ultrafine main phase
It became a Cu-rich phase. Main phase is TbCu7 type, Th_TwoN
i ₁₇Type, Th_TwoZn₁₇From any crystal structure of the mold
Single phase or TbCu7 type, Th_TwoNi₁₇Type, Th_Two
Zn₁₇Mold, ThMn₁₂Type, RE_ThreeT₂₉From mold
It was confirmed that it was a mixed phase. Also in each alloy
The composition of the Cu-rich phase is mainly that the amount of Cu is 20 atomic% or more.
Was analyzed. Next, from each alloy powder, isotropic bond
A magnet was produced and magnetic measurement was performed with a BH tracer. H
After DDR processing, the main phase is higher magnetic in the case of TbCu7 type
Properties were obtained, Br = 0.7 for the alloy of Example 20.
Br as high as 5T was measured. Each of Examples 1-36
Alloy composition, HDDR processing temperature, average grain size, etc.
Table 1 shows the results of measuring the magnetic characteristics of the anisotropic bonded magnet.

(Comparative Examples 1 to 10) Alloy powders and isotropic bonded magnets were produced in the same manner as in Examples 1 to 31, and the same B was obtained.
-H measurement was performed. Each alloy composition of Comparative Examples 1 to 10, HD
Table 2 shows the DR treatment temperature and the BH measurement result. Whereas the alloys of the examples include the Cu-rich phase, the alloys of the comparative examples include cases where Comparative Examples 1 to 3 do not contain Cu, and Comparative Examples 4 to 6 contain Cu and do not contain the Cu-rich phase. It was found that by including the Cu-rich phase, the alloy crystal grain size was finer than in the case where there was no Cu-rich phase, and the magnetic characteristics were excellent. In addition, the R element content of the alloys of Comparative Examples 7 and 8, 9, 10
It is essential for good magnetic properties that the A element contents of the alloys are all outside the limits of the alloy composition and the magnetic properties are extremely low, and that the R and A contents of the alloys are within the limits. all right.

(Examples 37 to 41) First, high-purity raw materials were mixed at a predetermined ratio shown in Table 2, high-frequency melted in an Ar atmosphere to prepare a master alloy ingot, and a mean powder was prepared using a mortar. It was crushed to a particle size of 106 μm or less. This alloy powder is continuously heated at 600 to 850 ° C. in 1 atm of hydrogen gas.
× 1 ~ 8 hours holding hydrogenation / decomposition reaction treatment,
Next, dehydrogenation of 700 ° C to 950 ° C for 0.1 to 2 hours in a vacuum of 13.33 Pa (0.1 Torr) or less.
A recombination reaction treatment was performed to produce magnet powder. X-ray diffraction analysis and TEM / ED of the production phase of each alloy powder at each processing stage
When examined by S, it was found that after HD treatment, mainly Nd hydrate and α-
The Fe phase was formed, and after the DR treatment, it was mainly a uniform and ultrafine main phase and a Cu-rich phase. The crystal structure of the main phase is Nd ₂ Fe
It was confirmed to be ₁₄ B type. The composition of the Cu-rich phase in each alloy was mainly analyzed to have a Cu content of 20 atomic% or more. Next, each alloy powder and an isotropic bonded magnet were produced and magnetic measurement was performed with a BH tracer. Example 39
In the case of the alloy No. 3, a high Br of Br = 0.68T was measured. Table 3 shows each alloy composition of Examples 37 to 41, HDDR treatment temperature, average crystal grain size, and magnetic property measurement results of the isotropic bonded magnet.

(Comparative Examples 11 to 13) Alloy powders and isotropic bonded magnets were produced in the same manner as in Examples 37 to 41, and the same BH measurement was performed. Table 4 shows each alloy composition of Comparative Examples 11 to 13, HDDR processing temperature, and B-H measurement result. The alloys of the examples include the Cu-rich phase, whereas the alloys of the comparative examples include Comparative Examples 11 to 12 not containing Cu and Comparative Example 13 containing Cu and not containing the Cu-rich phase. It was found that the inclusion of the Cu-rich phase resulted in a finer grain size of the alloy than in the absence thereof.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

[Table 4]

In Table 1, Table 2, Table 3 and Table 4, various combinations of R, T, M1, M2, Cu and A have been described. R, T, M1, M2, C
Similar results were obtained with other combination compositions of u and A. Further, substitution of 50% or less of Cu with Si,
You may perform by Ga, Zn, etc.

[0032]

As described above, according to the magnet material of the present invention, it is possible to provide a magnet material of an ultrafine crystal body which can realize high magnetic characteristics.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4K018 AA27 BB04 BC01 BC03 BC08                       BC09 KA45                 5E040 AA04 CA01 HB15 HB17 NN01                       NN18

Claims (5)

[Claims] 1. The general formula R _x (T _1-u-v-w Cu _u M
1 _v M2 _w ) _1−x−y A _y (wherein R is at least one element selected from rare earth elements including Y, T is at least one element selected from Fe or Co, and M1 is Zr, Ti, Nb, Mo, T
at least one element selected from a, W, and Hf, M2
Is at least one element selected from Cr, V, Mn, and Ni, A is at least one element selected from N or B, and x, y, u, v, and w each have an atomic ratio of 0.0.
4 ≦ x ≦ 0.2, 0.001 ≦ y ≦ 0.2, 0.002
.Ltoreq.u.ltoreq.0.2, 0.ltoreq.v.ltoreq.0.2, 0.ltoreq.w.ltoreq.0.2). A magnet material comprising a magnetic main phase and having an average crystal grain size of 100 nm or less in the hard magnetic main phase. 2. The crystal structure of the hard magnetic main phase is TbCu₇
Type, or Th_TwoNi₁₇Type, Th _TwoZn₁₇Mold, Nd
_TwoFe₁₄Claims characterized by being one of B type
Item 1. The magnetic material according to item 1. 3. The magnetic material according to claim 1, wherein the M1 always contains at least one element selected from Ti, Zr, Nb, Hf or Mo. 4. The magnet material according to claim 1, wherein the M2 always contains at least one element selected from Cr and V. 5. A raw material powder having an average powder particle diameter of 3 to 500 μm.
And then hydrolyzing and decomposing by holding at 450 to 850 ° C. for 1 to 8 hours in hydrogen gas of 0.1 to 10 atm or in an inert gas having a partial pressure of hydrogen gas other than nitrogen gas. And then 6 in a vacuum of 13.3 Pa or less.
A method for producing a magnet material, comprising the steps of holding at 00 ° C to 950 ° C for 0.1 to 3 hours to perform dehydrogenation and recombination reaction treatment.