JPH0574618A - Manufacture of rare earth permanent magnet - Google Patents

Abstract

PURPOSE:To obtain well-balanced magnetic characteristics, by pressure-molding mixed alloy powder in a magnetic field, sintering a molded object in a vacuum or an inert gas atmosphere, and performing aging heat treatment at a temperature lower than or equal to the sintering temperature. CONSTITUTION:A alloy is alloy which is mainly composed of R2T14B phase (R is rare earth metal whose main body is Nd, Pr, and Dy, and T is Fe or Fe and Co). B allay is alloy which contains R, Co, Fe, B, M (M is an element selected out of elements of Al, Cu, etc.). B alloy powder of 1-30wt.% is mixed in A alloy powder of 99-70wt.%, and mixed allay powder is subjected to pressure-molding in a magnetic field. The molded object is sintered in a vacuum or an inert gas atmosphere, and subjected to aging heat treatment at a temperature lower than or equal to the sintering temperature. Thereby well-balanced magnetic characteristics can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a rare earth permanent magnet having excellent magnetic properties, which is used in various electric and electronic devices.

[0002]

2. Description of the Related Art Among rare earth magnets, Nd-Fe-B based magnets are
Nd, which is the main component, is abundant in resources, low in cost, and excellent in magnetic properties, so that its use is expanding more and more in recent years. Since the invention of Nd-based magnets, research and development for improving magnetic properties have been vigorously carried out, and many studies and inventions have been proposed. There are also many methods for manufacturing high-performance Nd magnets by mixing and sintering two kinds of alloy powders with different compositions, which is one of the manufacturing methods for Nd-based sintered magnets. Invention proposals have been proposed.

The two alloy methods proposed so far can be roughly classified into three types. The first method is to prepare an amorphous or fine crystal alloy by liquid quenching one of the raw material alloy powders to be mixed, and mix it with a normal rare earth alloy powder, or to mix both raw material alloy powders together. A method of preparing and mixing by a liquid quenching method [JP-A-63-9
3841, JP-A-63-115307, JP-A-63-252403, JP-A-63-278
208, JP-A-1-108707, JP-A-1-146310, JP-A-1-146309,
See Japanese Patent Laid-Open No. 1-155603]. Regarding the two-alloy method using the alloy by this liquid quenching method, 50MG
Reported that magnetic properties exceeding Oe were obtained [E.Otuki, T.Otuka
and T.Imai; 11th.Int.Workshopon Rare Earth Magnet
s, Pittsburgh, Pennsylvania, USA, October (1990), p.328
Has been referred to].

In the second method, two kinds of raw material alloy powders to be mixed are mainly prepared as an R ₂ Fe ₁₄ B compound as an alloy in which the kinds and contents of rare earth elements are changed and mixed and sintered. Is the way. That is, a method of mixing two kinds of alloys in which the amount ratio of the contained Nd-rich phase or the kind of rare earth element is changed [JP-A-61-81603, JP-A-61-81604, and JP-A-61-816].
05, JP 61-81606, JP 61-81607, JP 61-11900
7, JP-A 61-207546, JP-A 63-245 Sho 3, and JP-A 1-177335].

In the third method, one alloy is mainly used as R ₂
A method for producing an Nd-based rare earth magnet by forming an alloy powder composed of a Fe ₁₄ B compound, and mixing and sintering powders of various low melting point elements, low melting point alloys, rare earth alloys, carbides, borides, hydrides, etc. JP-A-60-230959, JP-A-61-263201, JP-A-62-1
81402, JP 62-182249, JP 62-206802, JP 62-270
746, JP-A-63-6808, JP-A-63-104406, JP-A-63-114939,
See JP-A-63-272006, JP-A-1-111843, and JP-A-1-146308.

[0006]

There are many points that the two-alloy method according to the prior art is not appropriate or insufficient for realizing the truly excellent magnetic properties of Nd-based magnet alloys. That is, in the above-mentioned first method, the energy product of the magnet alloy is high, but the coercive force is about 9 kOe, and the coercive force is decreased by the temperature rise. Magnet characteristics. The biggest problem is magnetic field orientation. Even in the first method, an alloy exhibiting magnetism at room temperature can be obtained by appropriately selecting the composition. However, since the alloy obtained by the liquid quenching method becomes an amorphous amorphous phase or fine crystals, it is made into a fine powder and a magnetic field. Even if it is oriented inside, a specific crystal orientation cannot be oriented in the magnetic field direction. Therefore, even if the mixed raw material alloy powder is molded in a magnetic field, the orientation of the molded body obtained is poor,
Sufficient magnet characteristics cannot be obtained after sintering.

In the second method, R ₂ in the magnet alloy is
The phase coexisting with the Fe ₁₄ B compound is Nd-rich phase or Nd _{1 + X} F
It is an e ₄ B ₄ phase, and neither of them exhibits magnetism at room temperature. Therefore, the mixture of compounds having no magnetism disturbs the orientation, and a magnet having excellent magnetic properties cannot be obtained.
Also, in the third method using various elements and various compounds as the powder to be mixed, since these compounds do not have magnetism, the demagnetizing field becomes large during orientation in the magnetic field, and the effective magnetic field strength decreases, Therefore, the rotation of the magnetic particles in the magnetic field direction is insufficient and the orientation is disturbed.

[0008] In the third method, there is a proposal to improve the magnetic characteristics by using a low melting point element or alloy in the powder to be mixed. This is because the low melting point phase mixed during sintering is This is based on the idea that the lattice defects existing at the grain boundaries of the R ₂ Fe ₁₄ B compound and nucleation sites such as oxide phases are removed, and the grain boundaries are cleaned to improve the coercive force. However, the existence of the low melting point phase is actually a disadvantageous condition for the improvement of the magnetic characteristics for the following reason. If the low melting point phase becomes a melt from around 660 ° C., the viscosity of the low melting point phase becomes considerably small at the actual sintering temperature of 1,100 ° C. As a result, the compact is contracted by liquid phase sintering, and at the same time, the viscosity of the melt surrounding the grains is small, so that the rotation of the magnetic grains easily occurs, the orientation is disturbed, and the magnetic properties deteriorate. That is, a desirable liquid phase component in the liquid phase sintering of the Nd magnet is required to maintain an appropriate viscosity so as not to disturb the orientation of the particles, and also to densify the compact and sufficiently clean up the grain boundaries. In the conventional two-alloy method, the roles of both the magnetic field orientation and the coercive force improvement in which the liquid phase component is involved are fully taken into consideration, and the magnetism and melting point of the liquid phase alloy component are properly adjusted so that these conditions are optimal. I didn't adjust. The present invention aims to improve the above-mentioned drawbacks of the two-alloy method and to provide a method for producing a rare earth permanent magnet having excellent balanced magnetic characteristics.

[0009]

The inventors of the present invention have basically reviewed the two-alloy method in order to solve the above-mentioned problems, and properly select and combine the types and characteristics of the magnetic material constituent phases. The inventors have found that satisfactory balanced magnetic properties can be obtained, and studied the manufacturing conditions in detail to complete the present invention. The gist of the present invention is to mainly use the A alloy as R ₂ T ₁₄
Phase B (where R is at least 1 mainly composed of Nd, Pr and Dy)
(More than one kind of rare earth element, T represents Fe or Fe and Co)
And the B alloy is R, Co, Fe, B, M (where R is the same as above, M is Al, Cu, Zn, In, Si, P,
S, Ti, V, Cr, Mn, Ge, Zr, Nb, Mo, Pd, Ag, Cd, S
n, Sb, Hf, Ta, W, which represents one or more elements selected from the group), and R ₂ T as a constituent phase in the alloy.
¹ ₁₄ L phase and / or R rich phase (where R is the same as above, T ¹ is a transition metal element mainly composed of Fe and Co, the same transition metal and M (here, M is the same as above), L is B, B and M) and RT ² ₄ L phase, RT ² ₃ phase, RT
² ₂ phase, R ₂ T ² ₇ phase and RT ² ₅ phase (where R and L are the same as above, T ² is a transition metal element mainly composed of Fe and Co,
An alloy consisting of the same transition metal and B, the same transition metal and M, and the same transition metal and B and M) and a mixed phase with one or more of the five phases, and A alloy powder 99 to 70.
1 to 30% by weight of B alloy powder is mixed with respect to 1% by weight, the mixed alloy powder is pressure-molded in a magnetic field, the molded body is sintered in a vacuum or an inert gas atmosphere, and further below the sintering temperature. a preparation of a rare earth permanent magnet, characterized in that the aging heat treatment at a low temperature, more particularly, RT ² ₄ L contained in B alloy
Phase, RT ² _3-phase, RT ² ₂ phase, a melting point of at least one or more phases of the five constituent phases of R ₂ T ² ₇ phase and RT ² ₅ phase 700
℃ or more and 1,155 ℃ or less is an intermetallic compound, at least one phase is a magnetic material having a Curie temperature above room temperature, at least one phase is Curie temperature above room temperature and crystalline magnetic anisotropy It is a method for manufacturing a rare earth magnet, which is a magnetic substance having.

The present invention will be described in detail below. The present invention is a so-called two-alloy method, which is a rare earth permanent magnet (hereinafter referred to as magnet alloy C).
A) as a raw material is mainly composed of an R ₂ T ₁₄ B compound phase, and R is Y containing La, Ce, P
It is at least one kind of rare earth element mainly composed of Nd, Pr and Dy selected from r, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. T represents Fe or Fe and Co,
The Co content is 0.1-40% by weight. The addition of Co raises the Curie temperature of the A alloy and also improves the corrosion resistance of the alloy. The alloy A is cast by melting the raw material metal in a vacuum or an inert gas, preferably Ar atmosphere. As the raw material metal, pure rare earth elements or rare earth alloys, pure iron, ferroboron, and alloys thereof are used, but trace impurities unavoidable in general industrial production are included. In the obtained ingot, since the R ₂ T ₁₄ B phase is formed by the peritectic reaction of αFe and the rare earth-rich phase, the αFe phase, the R-rich phase, the B-rich phase, the Nd ₃ Co phase, etc. due to the solidification segregation after casting. May remain. In the present invention, since it is desirable that the R ₂ Fe ₁₄ B phase in the A alloy is large,
Solution treatment is performed if necessary. The conditions are vacuum or
The heat treatment may be performed in the temperature range of 700 to 1,200 ° C. for 1 hour or more under Ar atmosphere.

The B alloy is an alloy mainly composed of R, Co, Fe, B and M, and has a composition formula of R _a Fe _b Co _c B _{d Me} (where R
Is Y, including La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
At least one or more rare earth elements mainly composed of Nd, Pr and Dy selected from m, Yb and Lu, M is Al _, Cu _, Zn _, In _, Si _,
P _, S _, Ti _, V _, Cr _, Mn _, Ge _, Zr _, Nb _, Mo _, Pd _, Ag _, Cd _, Sn _, Sb _, Hf _, T
_a, represents one or more elements selected from among _W. The range of subscripts a, b, c, d, e is 15 ≦ a ≦ 40, 0 ≦
b ≤ 80, 5 ≤ c ≤ 85, 0 ≤ d ≤ 20, 0.1 ≤ e ≤ 20, a + b + c + d +
e = 100 (each atomic%)), and the raw material metal is melted and cast in a vacuum or in an inert gas, preferably Ar atmosphere, like the alloy A. As the raw material metal, pure rare earth elements or rare earth alloys, pure iron, pure cobalt, ferroboron, various pure metals, and alloys thereof are used, but trace impurities unavoidable in general industrial production are included. If the amount a of the rare earth element R is less than 15 atom%, the amount of R is too small to obtain a sufficient amount of liquid phase in the sintering process, and the density of the sintered body cannot be increased. The melting point becomes too low, and the effect of improving magnetic properties is lost. RT ² ₄ B phase in an amount c of Co is less than 5 atomic%, RT
^The phases such as the ² ₃ phase, the RT ² ₂ phase, the R ₂ T ² ₇ phase and the RT ² ₅ phase do not appear, and the effect of improving the magnetic properties cannot be obtained. Even if the thin strip obtained by the liquid quenching method is heat-treated, B
Alloys can be made. That is, in the liquid quenching method, the B alloy after quenching has an amorphous phase or a fine crystalline phase, and by heating this at a temperature not lower than the crystallization temperature for a certain time or more, crystallization or recrystallization growth is caused. hand,
Predetermined constituent phases of the present invention can be precipitated.

In this composition range, the phases mainly appearing in the B alloy are R ₂ T ¹ ₁₄ B phase (mainly R ₂ Fe ₁₄ B phase),
R-rich phase (wherein R is as defined above, T ¹ represents a transition metal element Fe, a Co mainly) and RT ² ₄ B-phase, RT
² ₃ phase, RT ² ₂ phase, R ₂ T ² ₇ phase and RT ² ₅ phase (here R
Is the same as above, T ² is a transition metal element mainly composed of Fe and Co, the same transition metal and B), etc., and in the present invention, at least one or more of the preceding two phases and the following five phases are used. It is characterized by using B alloy containing the phase of. R
The phase described as a rich phase represents all the various R-rich phases in which the R component is 35 atomic% or more. Of these seven types of phases, the _two phases, R ₂ Fe ₁₄ B phase and R rich phase, are phases that have also appeared by the conventionally known two-alloy method and the ordinary rare earth iron boron magnet alloy manufacturing method. is there. Remaining RT
² ₄ B-phase, RT ² _3-phase, RT ² _2-phase, R ₂ T ² ₇ phase, five phase RT ² ₅ phase emerges by adding 5 atomic% or more Co in B alloy, This is unique to the two-alloy method of the present invention. These five phases first appeared as an equilibrium phase in the B alloy by adding Co in an amount of 5 atomic% or more. FIG. 1 is an example in which a casting structure photograph of the B alloy of the present invention was photographed by a scanning electron microscope, and the composition was determined by EPMA (electron probe X-ray microanalyzer) and X-ray analysis.
1.RT ² ₄ B-phase, 2.RT ² _3-phase, 3.RT ^{₂ 2} phase, the presence of 4.R rich phase is represented clearly. The two-alloy method according to the present invention is characterized in that the B alloy contains at least one or more of these five phases, and the presence of these phases realizes high magnetic properties in the magnet alloy produced by the two-alloy method. I was able to do it.

In the present invention, the above-described alloy A and alloy B were mixed in a specific ratio, and the magnet alloy C was produced by the so-called two-alloy method, whereby high magnetic properties could be exhibited. Less than,
The reason why the existence of these mixed phases in the B alloy leads to the high magnetic properties of the magnet alloy will be described. The first reason is that these mixed phases have a Curie temperature above room temperature, which was achieved by the additive element Co. Further, these phases have magnetocrystalline anisotropy in a particular crystallographic direction. Therefore, when B alloy powder containing at least one of these phases as a main constituent phase is mixed with A alloy powder mainly composed of R ₂ Fe ₁₄ B phase and oriented in a magnetic field, B alloy also becomes a ferromagnetic material. Since it has magnetic anisotropy, almost all particles are oriented in the direction of the applied magnetic field with their crystal directions aligned, and high magnetic characteristics can be obtained.

The second reason is that the melting points of these phases are in a temperature range suitable for liquid phase sintering of Nd rare earth magnets, that is, 700.
It should be in the range of ℃ to 1,155 ℃. This temperature range is higher than the melting point of Nd-rich phase (500-650 ℃),
Moreover, the temperature is lower than the melting point (1,155 ° C.) of the R ₂ Fe ₁₄ B phase. Therefore, at the normal sintering temperature, only the Nd-rich phase is present and the viscosity of the melt is too low, and as a result, the orientation of the particles is not disturbed, and it becomes a liquid phase again. The density will be increased while cleaning the grain boundaries, and high magnet characteristics will be realized after sintering. Another effect of the addition of Co is improvement in corrosion resistance. Since alloy B contains more rare earth elements than alloy A, it is prone to oxidative deterioration, but by adding Co, oxidative deterioration can be prevented and stable magnetic properties can be obtained. Further, addition of Co to the A alloy also improves the corrosion resistance of the alloy, reduces oxidative deterioration, and provides stable magnetic properties. A large amount of Dy added to the B alloy exists near the grain boundaries even after sintering, and has the effect of improving the coercive force of the magnet alloy C. Similarly, various elements M added to B alloy (here M
Is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, Mn, G
e, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, and W, which represent one or more elements selected from W), also improve the coercive force of the magnet alloy C. There is.

Next, a method for producing the magnet alloy C by the two-alloy method will be described. The A alloy and the B alloy obtained as described above are separately crushed and then mixed in a predetermined ratio. The crushing is performed by wet or dry crushing. Rare earth alloys are very active, in order to prevent oxidation during grinding, in an atmosphere such as Ar or nitrogen for dry grinding, in a non-reactive organic solvent such as CFC for wet grinding. Done. The mixing step is also performed in an inert atmosphere or a solvent as needed. Grinding is generally carried out in stages such as coarse grinding and fine grinding, but mixing may be carried out at any stage.
That is, a predetermined amount may be mixed after coarse pulverization and then fine pulverization may be performed, or a predetermined ratio may be mixed after all pulverization is completed. Both A and B alloys need to be uniformly mixed with almost the same average particle size, and the average particle size is preferably in the range of 0.5 to 20 μm.
If it exceeds, the sinterability will deteriorate.

The mixing ratio of the A alloy powder and the B alloy powder is A
It is preferable to mix the B alloy powder in the range of 1 to 30% by weight with respect to 99 to 70% by weight of the alloy powder. If the B alloy powder is less than 1% by weight, the sintered density will not be increased and coercive force will not be obtained. If it exceeds 30% by weight, the proportion of the non-magnetic phase after sintering becomes too large and the residual magnetic flux density becomes small. The obtained mixed fine powder of A alloy and B alloy is then molded into a desired size by a molding press in a magnetic field, and further sintered and heat treated. Sintering is performed in a temperature range of 900 to 1,200 ° C. in a vacuum or an argon atmosphere for 30 minutes or more, and then an aging heat treatment is performed at a temperature lower than the sintering temperature for 30 minutes or more. After sintering, magnet alloy C
The density of the molded body of (1) is densified to 95% or more in terms of the true density ratio, and a high residual magnetic flux density can be obtained.

[0017]

EXAMPLES Hereinafter, specific embodiments of the present invention will be described with reference to examples, but the present invention is not limited thereto. (Example 1, Comparative Example 1) An alloy of composition formula 12.5Nd-6B-81.5Fe (each atom%) using Nd, Fe metal having a purity of 99.9% by weight and ferroboron was used in an Ar atmosphere of a high frequency melting furnace. After melt casting, this ingot was heated at 1,070 ℃ in Ar atmosphere.
It was solidified for 20 hours. This is designated as A1 alloy. Next, an alloy of composition formula 20Nd-10Dy-20Fe-6B-40Co-4Al was similarly melt-cast in an Ar atmosphere using a high-frequency melting furnace by using Nd, Dy, Fe, Co, and Al metals with a purity of 99.9% by weight and ferroboron. This was designated as B1 alloy. A1 alloy ingot and B1 alloy ingot are separately crushed separately in a nitrogen atmosphere and 30
A mesh or less was prepared, and then 10% by weight of the B1 alloy coarse powder was weighed with 90% by weight of the A1 alloy coarse powder and mixed for 30 minutes in a nitrogen-substituted V blender. This mixed coarse powder was finely pulverized with a jet mill using high-pressure nitrogen gas to an average particle size of about 5 μm. The obtained mixed fine powder was press-molded at a pressure of about 1 Ton / cm ² while orienting in a magnetic field of 15 kOe. Then
This compact was sintered in an Ar atmosphere sintering furnace at 1,070 ° C for 1 hour, and then aging heat-treated at 530 ° C for 1 hour to quench.
A magnet alloy C1 was produced.

For comparison, an alloy having the same composition as that of Example 1 was manufactured by the conventional one-alloy method to obtain Comparative Example 1. That is,
The same composition (magnet alloy C1) after mixing both A1 and B1 alloys was weighed from the beginning, melted, crushed, sintered, and aged heat treated to 2
The magnetic characteristics were compared with the magnet by the alloy method (magnet composition C1 of Example 1). The composition of this magnet alloy C1 is 13.1 Nd-in both Example 1 by the two-alloy method and Comparative Example 1 by the one-alloy method.
It is 0.8Dy-3.2Co-6.0B-0.3Al-76.6Fe. Table 1 shows magnetic property values and sintered body densities obtained for both the sintered body magnets of Example 1 and Comparative Example 1. The magnetic properties of Example 1 are almost the same as those of Comparative Example 1 in terms of the density of the sintered body, but Example 1 is much superior in all values such as the residual magnetic flux density, the coercive force, and the maximum energy product. There is. Thus, even if the composition of the magnet alloy C is exactly the same, there is a considerable difference in the magnetic characteristics, which indicates that the two-alloy method is an extremely effective method for improving the magnetic characteristics of the Nd magnet. The metal structure of the B1 alloy in the cast state is shown in FIG. 1 by a backscattered electron image photograph of a scanning electron microscope. As can be seen from the lightness and darkness of the photograph, there are four main constituent phases in the B1 alloy. Each phase was analyzed by EPMA (electron probe X-ray microanalyzer) and X-ray analysis, and as shown in the figure, RT ² ₄ B phase, RT ² ₃ phase, RT ² ₂
Phase and R-rich phase.

(Examples 2 to 24, Comparative Examples 2 to 24) As shown in Table 1, Table 2 and Table 3, corresponding to the alloy compositions of Examples 2 to 24, compositions of A2 to A24 as A alloys. An alloy is prepared, a composition alloy of B2 to B24 is prepared as an B alloy, and crushed in the same manner as in Example 1 below, mixed at a predetermined ratio, molded in a magnetic field, and sintered (1,050 to 1,120 ° C. × 1 hour), Aging treatment (500 to 650 ° C x 1 to 10 hours) was performed to produce a two-alloy method magnetic alloy C2 to C24, the magnetic characteristics of which were measured, and Table 1,
The results are shown in Tables 2 and 3. Example 2 except that an alloy having the same composition as in Examples 2 to 24 was prepared by the 1-alloy method for comparison.
Magnetic alloys C2 to C24 were manufactured under the same conditions as those for .about.24, and the magnetic properties were measured to make Comparative Examples 2 to 24, which are shown in Table 1, Table 2 and Table 3.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

[Table 3]

[0023]

EFFECTS OF THE INVENTION The rare earth permanent magnet manufactured according to the present invention effectively utilizes expensive additive elements and has several magnetic properties superior to those of the conventional rare earth magnets having the same composition. It has become possible to provide a high-performance magnet with a well-balanced residual magnetic flux density and high energy product. Therefore, it is expected to be widely used in the future as a high-performance magnet for various electric and electronic devices.

[Brief description of drawings]

FIG. 1 is a scanning electron micrograph showing a metal structure of a B1 alloy of Example 1 in a cast state.

[Explanation of symbols] 1 RT ² ₄ B phase 2 RT ² ₃ phase 3 RT ² ₂ phase 4 R rich phase

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 10, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction content]

In the second method, two kinds of raw material alloy powders to be mixed are mainly prepared as an R ₂ Fe ₁₄ B compound as an alloy in which the kinds and contents of rare earth elements are changed and mixed and sintered. Is the way. That is, a method of mixing two kinds of alloys in which the amount ratio of the contained Nd-rich phase or the kind of rare earth element is changed [JP-A-61-81603, JP-A-61-81604, and JP-A-61-816].
05, JP 61-81606, JP 61-81607, JP 61-11900
7, JP 61-207546, JP 63-245 90 3, Hei 1-177335 is the JP reference.

Claims (5)

[Claims] 1. An A alloy mainly composed of an R ₂ T ₁₄ B phase (where R
Is an alloy of at least one or more rare earth elements mainly composed of Nd, Pr, and Dy, and T represents Fe or Fe and Co), and B alloy is R, Co, Fe, B, M (here, R is Is the same as above, M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr,
Mn, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, W
(Representing one or more elements selected from among the above), and R ₂ T ¹ ₁₄ L phase and / or as a constituent phase in the alloy
Or R-rich phase (where R is the same as above, T ¹ is Fe,
A transition metal element mainly composed of Co, the same transition metal and M (where M is the same as above), L represents B, B and M), and RT ² ₄ L phase, RT ² ₃ phase, RT ² ₂ phase , R ₂ T ² ₇ phase and RT ² ₅ phase (where R and L are the same as above, T ² is F
Transition metal elements mainly composed of e and Co, transition metals and B, transition metals and M, transition metals and B and M
The alloy consisting of one or two or more mixed phases of the five phases of
The alloy powder is mixed in an amount of 1 to 30% by weight, the mixed alloy powder is pressure-molded in a magnetic field, the compact is sintered in a vacuum or an inert gas atmosphere, and further subjected to an aging heat treatment at a temperature lower than the sintering temperature. A method of manufacturing a rare earth permanent magnet, characterized in that 2. RT ² ₄ contained in the B alloy according to claim 1.
L-phase, RT ² _3-phase, RT ² ₂ phase, a melting point of at least one or more phases of the five constituent phases of R ₂ T ² ₇ phase and RT ² ₅ phase 70
A method for producing a rare earth permanent magnet, which is an intermetallic compound having a temperature of 0 ° C to 1,155 ° C. 3. A rare earth magnet, wherein at least one of the five constituent phases contained in the B alloy according to claim 1 or 2 is a magnetic material having a Curie temperature of room temperature or higher. Manufacturing method. 4. Among the five constituent phases contained in the B alloy according to claim 1, 2 or 3, at least one kind of phase is a magnetic material having a Curie temperature of room temperature or higher and a crystalline magnetic anisotropy. A method of manufacturing a rare earth magnet, characterized by being present. 5. The A alloy, B alloy and A according to claim 1.
A method for producing a rare earth magnet, wherein the B mixed alloy powder has an average particle size within a range of 0.5 to 20 μm.