JPS59204212A - Isotropic permanent magnet and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain an isotropic permanent magnet provided with a high Curie point by a method wherein an Fe.Co.B.R.M (an addition element) alloy and an Fe.Co.B.R.M.A (an element of the prescribed percentage) alloy are used making especially an Fe.B.R (R: a rare earth element containing Y) alloy as a base. CONSTITUTION:An alloy using electrolytic iron of 99.9% purity as the Fe, a ferro boron alloy and boron of 99% purity as the B, a material of 99.7% purity or more as the R, and electrolytic Co of 99.9% purity as the Co is used as a starting material to be dissolved according to high-frequency dissolution, and casted by a water-cooled copper mold. Ti, Mo, Bi, Mn, Sb, Ni, Ta of 99% purity, W of 98% purity, Al of 99.9% purity, Hf of 95% purity are used as the M, and moreover ferro vanadium containing V of 81.2%, etc. are used as the V, S of 99% purity or more, ferro phosphate containing P of 26.7%, etc. are used as the element A, and pulverized to the degree of 3-10mum according to a stamp mill and a ball mill. After then, molded applying pressure of the degree of 1.5t/cm<2>, sintered at 1,000-1,200 deg.C, and cooled finally.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to isotropic permanent magnets, particularly Fe*Co*B*RsM and Fe magnets based on FeBR alloys.

-Relating to a new magnet represented by B-R-M-A.

In the present invention, R is a rare earth including yttrium Y, M is an additive element such as aluminum A1, nickel Ni, manganese Mn, etc., and A is a symbol representing an element such as copper Cu, phosphorus P, carbon C, sulfur 4/(3), etc. .

Permanent magnets play an important role in electronic devices. There are mainly three types of permanent magnets currently in use: alcoco magnets, ferrite magnets, and XJ earth cobalt magnets. With the recent remarkable progress in semiconductor equipment, the limbs and mouth (speech) of electronic equipment
Components are also required to be smaller and have higher performance, and the permanent magnets used in these components are also required to have higher characteristics.

As a permanent magnet, anisotropic magnets usually exhibit higher performance than isotropic magnets, but isotropic permanent magnets have a large number of uses and demand due to their magnetic properties, which are not restricted by shape or direction of magnetization. High-performance magnets are in demand.

Generally, isotropic magnets are made of most of the same materials as anisotropic magnet materials. However, alnico magnets and ferrite magnets with a maximum energy ML (BH) max of 2 MGOe or less have been put into practical use. In addition, formal class cobalt (R
Co) SmCo magnets as magnets exhibit high characteristics with 4 NGOe and isotropic magnets, but are 174 to 1/B of these anisotropic magnets, and require Samariu ASm, which is a rare resource. 50% of cobalt CO whose supply is unstable
It is very expensive because it needs to be used in a large amount of ~60% by weight.

゛ Light rare earths such as Ce, Nd, Pr, etc., which are abundant in resources, are used instead of heavy rare earth Sm, and F is used instead of CO.
However, it is well known that light rare earths and Fe do not form intermetallic compounds suitable for magnetization even when homogeneously melted into phase Q and crystallized by cooling. Furthermore, an attempt to strengthen the magnetic force of such a light rare earth-Fe alloy by powder metallurgy was not successful (see JP-A-57-210934 specification 6).

On the other hand, it is known that Fe-R (Fe, Ni, Go)-R amorphous alloys can be obtained by melt quenching. It has been proposed that a binary alloy of (B
H) max is 4 to 5 MGOe can be obtained, but
Since the ribbon is several microns to several tens of microns thick, it requires lamination or pressing after powdering to make it practical/hertz, and either method lowers the theoretical density and further deteriorates the magnetic properties, making it impractical. It's no longer something that
.

The basic objective of the present invention is to provide a new practical permanent magnet to replace these conventional isotropic permanent magnet materials,
In particular, as R, there is no need to use materials with abundant resources such as rare and expensive Sm, and there is no need to use a large amount of Go. Furthermore, it is an object of the present invention to provide an isotropic permanent magnet (material) having a Curie point (temperature characteristic) that is sufficiently high for practical use, and a method for manufacturing the same.

As a result of research to achieve this IJ characteristic, the present inventors have developed a magnet that has a sufficiently high Curie point, can be manufactured using practical raw materials and manufacturing processes, and has magnetic properties equivalent to or higher than that of SmCo magnets. We were able to obtain a magnetically isotropic sintered permanent magnet having the following properties.

II. The magnetically isotropic sintered permanent magnet of the present invention has, as a first aspect, 10 to 25% R (wherein R is at least one of the n-earth elements including Y), 3 to 23 %
of B, Go of 50% or less (excluding Go OX)
, a predetermined percentage of one or more additive elements M (excluding MOX, where M is AI8.
7'% or more F, Ti 4.3% or less, v a, 7
z or less, Cr 8.3% or less, Mn 8.0
% or less, Zr 5.5X or less, Hf 5.0
% or less, Nb 12.4% or less, Ta 1
0.3% or less, No. 8.7% or more, Ge
5.7% or less, Sb 2.4% or less, Sn
3.5% or less, Bi 4.8% or less, Ni
4.3% or less, and W 8.8% or less and contains two or more types, the total amount of M is less than the atomic percentage of the one having the maximum value among the added elements), and the balance is Fe and impurities unavoidable in manufacturing. (first composition).

The present invention further provides, as a second aspect, an anisotropic sintered permanent magnet comprising the above-mentioned first composition and the following components. That is, the first composition plus a predetermined percentage of one or more of the elements A (1+1+A 0%, A,!: L Te copper Cu 3.3% or more).

・Sulfur S2.5% or less, carbon C4.0% or more and 97
23.3% or less), provided that when A is M1, the content of M and A is the atomic percentage of the element having the maximum value among the M and X elements contained. +< (second composition).

Furthermore, the permanent magnet of the present invention has an average crystal diameter of about 1 to 100 #In by setting the average crystal diameter of the sintered body to about 1 to 100 #In.
1 (it gives rise to c), and is applicable to both the first and second compositions of item 2.

The permanent magnet of the present invention is manufactured by press-molding and sintering the alloy powder having the first or second composition. This alloy is a new crystalline alloy, and no alloy with such a composition that has a Curie point Tc of 1 as shown in FIG. 1 has been hitherto known. The alloy obtained by melting to a predetermined composition, cooling (usually casting), is pulverized, pressure molded, and then sintered.

The role of Go in the permanent magnet of the present invention is basically to improve the temperature dependence of the magnetic properties by increasing the Curie point.

By replacing Fe with CO, 5 CO is added to the alloy composition.
By containing 0% or less (atomic percentage), the warming properties are improved to a more practical level. Co(7
) content is small compared to SmCo magnets (containing 5.0 to 60% by weight of Co), and high magnetic properties are achieved by using light rare earth elements such as neodymium Nd and praseodymium Pr, which are abundant in resources, as the rare earth element R. obtained, and the present invention is a conventional RCo
(Compared with di-stone (almost limited to SmGo), it is advantageous in terms of both resources and cost, and even better magnetic properties can be obtained.

- Generally, when Go is added to an Fe alloy, the Curie point (Tc) may increase or decrease depending on the increase in the amount of addition, and it is difficult to predict the result. According to the invention, Fe
As shown in FIG. 1, the substitution of G with CO.

Tc gradually increases as the amount of substitution increases. Regarding Tc, a similar tendency is confirmed in the present invention regardless of the type of R. Even a small amount of Go substitution has a 41 effect on increasing Tc, and the system (78-x) Fee x exemplified in FIG.
As is clear in Co*8B@15Nd-LM, an alloy having an arbitrary Tc of about 300 to 700°C can be made by adjusting C0j11.

In the permanent magnet of the present invention, B is coercive force iHc IKOe
In order to obtain the following 1-3% (atomic percentage, the following % indicates the raw r-percentage in the alloy) and
In order to obtain a residual magnetic flux density Br of approximately 3 KG or more, B is set to be 23% or less (see FIG. 8). In this range (BH)
max 2 MGOe or more can be obtained.

R is required to be 10% or more in order to make the coercive force IKOe or more, and since the coercive force increases as the R content increases and then decreases, it is necessary to make the coercive force IKOe or higher. In addition, because it is easily flammable, difficult to handle and manufacture industrially, and is expensive, it is set at 25% or less (see Figure 9).

As R, eaves earth, which is rich in resources, can be used, and since Sm is not necessarily required or Sm does not need to be the main component, the raw material is inexpensive and extremely useful.

R used in the permanent magnet of the present invention includes Y and includes light rare earths and heavy rare earths, and one or more of them is used. That is, Nd, Pr, lanthanum La, cerium Ce, terbium Tb, dysprosium Dy, holmium Ho, erbium Er, europium Eu, samarium Sm, gadolinium Gd, promethium Pm
, Thulium Tm, Ytterbium Yb, Lutetium L
u, and Y, etc.

As R, a light rare earth element is sufficient, and Nd and Pr are particularly preferred. Further, normally one type of R is sufficient, but in practice, a mixture of two or more types such as mitshumetal, didymium, etc. can be used for convenience of availability, and Sm.

La, Ce, Gd, Y, etc. can be used in combination with other light rare earths such as Nd and Pr. Note that R does not have to be a pure rare earth element, and may contain impurities that are unavoidable in production within an industrially available range.

As B, pure boron or ferropolon can be used, and materials containing nitrogen N, silicon Si, etc. as impurities can also be used.

In principle, by adding the additive element M, the coercive force iH
It is possible to improve c. M is AI, Ti
, V, (Er, Mn, Zr, Hf, Nb,
Ta, Mo, Ge.

Sb, Sn, Bi, Ni, and W can be used singly or in combination. Also, the coercive force (iHc) is -・
Although it generally decreases with temperature -L'tl, the iHc at room temperature can be increased by containing M, and demagnetization can be substantially prevented even when exposed to high temperatures.

[7 Since M is a nonmagnetic element (excluding Ni), Br decreases as the addition of -111 increases, and therefore (U)I)wax decreases. (BH) Since there are many applications requiring a high iHc even if the wax is slightly lowered, alloys containing M are very useful. However, it is useful for OH)max to be in a range of 2 MGOe or more.

The effect of adding M on Br was confirmed by varying the amount of M added, and it was found that the addition of M was necessary to make the hard ferrite level (BH) equal to or higher than about 2 MGOe. The upper limit of the amount is as shown in Figures 2 to 5. AI 8.7X Ti 4.3$
V 8.7% Cr 8.3% Mn
8. B Zr 5.5% If 5.
0% Nb 12.4% Ta 10.3%
Mo 8.7% Ge 5.7X
Sb 2.4XSn 3.5 pieces Bi
4. HNi 4. HW 8.8OA.

When two or more types of M are added and contained, characteristics synthesized according to the component ratio of each M are usually exhibited, and the content of each M is within the range of % shown in L, and the total amount is within the range of the above-mentioned for the relevant element added at the site. % or less. In addition, when two or more types of M are contained, the properties are similar to those shown in FIGS. 2 to 5, which are the properties obtained by combining the properties when the M is used alone. This also applies to cases where other elements A are included.

Since the addition of M causes a gradual decrease in the residual magnetization Br, the M content should be at least in a range equal to or higher than the Br value of conventional RCo magnets, and the magnet of the present invention should exhibit a high coercive force equal to or higher than that of conventional RCo magnets. It is understood as a target.

The addition of M basically has the effect of increasing the coercive force iHc, thereby increasing the stability of the magnet and expanding its uses. In cases where Naori r is 4, 5 or 6KG or more, Mi! By selecting -, a preferable addition h: can be determined.

Another permanent magnet (second composition) of the present invention contains a predetermined percentage of element *A.
The following contains Cu as A, S,
When manufacturing Fe@co-BIIR@M magnets industrially, the content of C, P, etc. is 1 due to raw materials, manufacturing processes, etc.
It is often done. For example, when FeB is used as a raw material, S
, P are often contained, and C is often contained as a residue of an organic binder (molding aid) in the powder metallurgy process. Cu is sometimes contained in large amounts in low-purity and inexpensive raw materials. It is recognized that the influence of the content of A is that the residual magnetic flux density Br tends to decrease as the content increases (see FIG. 7).

Sono result Cu 3.3Z or less, 35% or less, C4,
If the P content is 0% or less and P is 3.3% or less, properties equivalent to or better than hard ferrite can be obtained. 2 or more types of A]
- If contained, the content shall be less than or equal to the one with the maximum value among the contained elements. However, the characteristics in the case of two or more types of A are almost the same as those obtained by combining the characteristics of each element A.

Thus, the content of element A within a predetermined range has great advantages in practical and industrial production.

When the isotropic permanent magnet FeeCo*BeR*M system (first composition) of the present invention further contains A (second composition) M,
The properties due to the inclusion of A are almost the same as when two or more types of M or A are included.

Note that the inclusion of A does not have a significant effect on Tc within the composition range of the present invention.

When manufacturing the permanent magnet of the present invention, the alloy is melted in a vacuum or in an inert gas atmosphere, and a mold made of copper or other metal is used for casting. It is desirable to speed up the cooling rate by using a mold or the like.

After cooling sufficiently, coarsely pulverize with a stamp mill, etc., and then finely pulverize with an attritor, ball mill, etc. to approximately 4001 tons.
m or less, preferably 1 to 100 m.

In addition to the methods mentioned above, methods for obtaining finely pulverized powder of FeBR alloys include mechanical pulverization methods such as spraying methods, reduction methods,
Physicochemical milling methods such as electrolytic methods can also be used.

This fine powder alloy was press-molded by a conventional method to obtain a molded product of approximately 9.
00~1200℃, preferably 1050~1150'O
Sinter at a temperature of for a predetermined period of time. By selecting sintering conditions (particularly temperature and time) so that the average crystal grain size after sintering falls within a predetermined range, an isotropic sintered magnet body with high magnetic properties is obtained. For example, a sintered body with a preferable crystal grain size can be obtained by molding an alloy powder of 100 .mu.1 m or less as a starting material and sintering it at a temperature of 1050 to 1150.degree. C. for 30 minutes to 8 hours.

Note that sintering is preferably performed in vacuum or in an inert gas atmosphere. Furthermore, during molding, binders such as camphor, paraffin, resin, and ammonium chloride, and lubricants and molding aids such as zinc stearate, calcium stearate, paraffin, and resin can be used.

As shown in Figure 6, the average crystal grain size of the sintered body is approximately 1 to 11
007t TeiHc Gives IKOe or more, 2-40
p, m, and 3 to 151 each indicate a preferable or more preferable range.

The present invention will be described in detail below using Examples, but the present invention is not limited thereto.

Fe-Coo B*R*M containing predetermined additive elements
Permanent magnet samples made of alloy and Fe-Co.B.R-A alloy were prepared in the following manner.

(1) The starting material is electrolytic iron with a purity of 89.9χ as Fe,
Ferroboron alloy and 99% purity boron as B;
An alloy using electrolytic Go with a purity of 98.7% or more as R (the impurities are mainly rare metals such as Toshito and others) and 99.9% purity as Co is high-frequency melted and made in a water-cooled copper mold. Cast. M is Ti with a purity of 98%, and No.

Bi, Mn, Sb, Ni, Ta, 98% NOW, 99.8% NOAI, 95% Hf, and NOEROVANADIUM containing 81.2$ glue as V, 67.6% Nb as Nb. Contains ferroniobium, 61 as Cr
．． 75 as ferrochrome and H-Zr containing 9% Or
．． Ferrozirconium containing 5% Zr was used.

Element A is ferroline with a purity of 99"X or higher, S, 26.7X or higher, and a C5 purity of 99, with a purity of 88% or higher.
．． Electrolytic Cu of 9% or more was used. However, the purity of the raw material metal in item 114 is expressed in % by weight.

(2) Grinding: Coarsely pulverize to 35 mesh through using a stamp mill and then pulverize using a ball mill.
7I) Fine grinding (3-10 JLm).

(3) Molding: Pressure of 1.5t/cm' - Molding (4) Sintering: 1000-1200'07)
ly Co' 7 Sintered in Ar for 1 hour so that the average crystal grain size of the sintered body becomes 5 to 30 gm. Allow to cool after sintering.

iHc, Br for the above samples with various compositions.

Magnet characteristics were investigated by measuring (BH)max. 1st
Permanent magnet characteristics 111 for representative samples in Table and Table 2
c, Br, (BH)nIax is shown. In addition, Fe in the table
The amount is the remainder. Also, as R, Nd, Pr, Gd,
Examples of alloys containing Ha and La were listed in January, but there are 15 types of rare earth metals (Y, Ce, Sm, etc.).

Eu, Tb, Dy, Er, Tm, Yb, L
u, Nd, Pr, Gd, Ha.

La) have similar properties. However, Nd and Pr are contained in relatively large amounts in the ores, especially Nd.
It is far more advantageous than alloys whose main raw materials are other rare earths (Sm, y, heavy rare earths) because their applications in large quantities are not yet known.

Examples of the present invention are shown in Table 1.2.
As a result of investigating the relationship between the average grain size D (pm) and its coercive force 1) 1c (KOe) for No. 14 in the table and No. 28 in Table 2, the relationship shown in Figure 6 was obtained. Ta.

Note that FIG. 6 is based on a sample manufactured in the same manner as described above, except that the conditions were changed in the manufacturing method so that the crystal grain size varied. As a result, it has become clear that in order to effectively utilize the characteristics of the permanent magnet of the present invention, it is preferable to adjust the average crystal grain size within a predetermined range.

Figure 2.3 shows Fe −15C:o −8B −15Nd
- Samples obtained in the same manner as above, with X changed from 0 to 15 atomic % in KM.

Figure 4.5 shows Fe -IGo -8B-15Nd -1
M, it was obtained in the same manner as in Fig. 2.3.

Figure 7 shows Fe −15C:o −8B −15Nd −
xA is based on a sample obtained in the same manner as above except that X was varied from 0 to 10 atomic %. This tendency is M
The same applies when it includes.

(hereafter 1 and t3) Table 1 Magnet properties 8°° Composition (atomic χ) (BH). 88
1(c(KOe) Br(KG) (MGOe)l
Fe-5Co--8B-15Nd-2AI
12.4 5.8 B, 52 Fe-20Go-88
-13Nd-0,5A1. 10. [i 4.9
4-73 Fe-35Go-13B-17Nd-IT
i 8.8 4.6 4.14 Fe-10G
o-17B-14Nd-3Ti 7.8 3.5
2.55 Fe-2Go-10B-+6Nd-3V
9.2 ・3.2 2.1
8 Fe-15Go-78'-14Nd-2C:r
7.2 4.4 3.97 Fa-25GO-
7B-14Nd-IMn 8.8
5.4 5.78 Fe-5Go-9B-15N
d-iZr 8.0 5.2 5.39 Fe
-20Go-17B-14Nd-G, 5Zr 1
0.1 3.9 3, IIQ Fe-10co-10B
-15Nd-5Zr 7.8 3.3 2.21
1 Fe-15Co-88-14Nd-IHf
11.4 5.5 6.2+2 Fe-2C
o-7B-15Nd-INb 7.3 5.9
7,2+3 Fe-10Co-8B-16Nd-3
Nb 7.3 4.7 4.
514 Fe-30Go-7B-15Nd-BNb
7.8 3.5 2.415 Fe-20Go
-13B-14Nd-3Ta 8.6
5.1 5. +16 FeFe-3Go-8B
-15Nd-I 8.8 8.1
7.717 Fe-15Co-8B-15Nd-
1,5Mo 13.5 8.0? , 418
Fe-25Go-BB-1? Nd-5Mo'
9.4 5.2 5.1 2nd
Table The permanent magnet of the present invention can be manufactured using industrially available materials, and it is extremely advantageous to use light rare earth elements as the central element of the magnet material.

Heavy rare earths are rare and expensive resources and generally have little industrial utility value, but it is advantageous to use them in combination with light rare earths.

Since an increase in coercive force contributes to stabilizing its magnetic properties, the addition of M makes it possible to obtain a permanent magnet that is extremely stable in practice and has a high energy product.

In the present invention, even a small amount of Go substitution is effective in increasing Tc, and since CO has more corrosion resistance than Fe, the inclusion of Go also imparts corrosion resistance to the magnet.

As detailed above, the present invention provides a permanent magnet made of a magnetically isotropic sintered body made of a FeeCo・BRM-based alloy and a Fe@co-B-RIIM-x based alloy, and provides a permanent magnet that is superior to the conventional level. Magnetic properties are achieved without using any expensive materials. Furthermore, it has a higher coercive force than conventional products,
To provide an isotropic permanent magnet which has a high energy product and has temperature characteristics substantially comparable to conventional alnico and RCO magnets. In addition, by using a light rare earth element such as Nd or Pr as R, the permanent magnet is practical in terms of resources, cost, and magnetic properties, and has high utility in the L industry.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the Go content (horizontal axis) and the Curie point (vertical axis) of the permanent magnet example of the present invention, Nos. 2 to 5.
The figure is a graph showing the relationship between the content of the additive element M (horizontal axis) and the residual magnetization Br (KG) in the example of the present invention, and Figure 6 is the average crystal grain size ( Figure 7 is a graph showing the relationship between the content of element A and Br (KG), and Figure 8.9 is a graph showing the relationship between the horizontal axis) and coercive force iHc.
Graphs showing the relationship between the contents of B and R and 111c and Br are shown. Applicant Sumitomo Special Metals Co., Ltd. Agent Patent Attorney Asa Kato Brush stroke 1 Figure Fe-xCo-8B-15Nd-M Mow, Cr, V Co + color separation (X%) Figure 2 Fe-15Co -8B-15Nd-xMM original-! r white scale (8%) Figure 6 1 5 10
5Q 100-P Inner thread crystal coarse color 0 (μm) Fig. 7Fe-15Co-88-15Nd-xAArin Isakijuku (X
Renal Diagram 8Fe-10Co-x-8-15Nd-IW8 Irregularity:! r white equinox year (X%) Fig. 9Fe-10co-88-x-Nd-IWNd 7t 3
6 mintx%)

Claims (6)

[Claims] (1) atomic percentage of 10 to 25% R (R is at least one rare earth element including Y), 3 to 23% (7
) B, 50% or less Co (excluding LCO 0%), one or more of the elliptic elements M at a predetermined percentage (however, M O
Except for z, here M is AI 8.7% or less, Ti 4.3% or less,
V 8.7%: or less, Or 8.3X or less,
Mn 8.0% or less, Zr 5.5% or less,
Hr 5. ox or less, Nb 12.4% or less,
Ta IQ, 3% or less, Mo 8.7% or less, Ge 5.75. 'Below, Sb 2.4%
Below, Sn 3.5$ or less, Bi 4.8*
Hereinafter, if two or more types are included in N+ 4.3% or less, and lil 8.8% or less, the total amount of M is not more than the atomic percentage of the one having the maximum value among the added elements), and the balance is Fe and the manufacturing 1 non-σfa. Magnetic isotropic sintered permanent magnet consisting of impurities. (2) 10 to 25% R (R is at least one rare earth element including Y), 3 to 23% B in atomic percentage
, 50% or less Co (excluding CoOz), one or more types of additive element M (however, M
Except for Oyo, here M means Al 8.7% or more, Ti 4.3% or less, V 8.7% or less, Cr 8.3% or more, Mn 8. More than 0%,
Zr 5.5% or less, Hf 5. Below OX,
Nb! 2.4X or less, Ta 10.3'A
Ar1 No 8.7% or less, Ge 5.7
% or less, Sb 2.4% or less, Sn L5%
Hard, Bi 4.8% or less, Ni 4
, 3% or less, and w 8.8'
Except for OX, A is Cu 3.3% or less, S 2.5% or less, C
4.0% or less, and P 3.3% or less), provided that the total amount of M and A is not more than the atomic percentage of the element having the maximum value among the M and A elements contained, and the balance is Fe and manufacturing heat. A magnetically isotropic sintered permanent magnet consisting of unavoidable impurities. (3) 10 to 25% R in atomic percentage (R is at least one kind of rare earth element including Y), 3 to 23% L
:r) B, 50% or less (7) Go (However, LCo O
'X'j-), a predetermined percentage of one or more of the additive elements M (however, excluding M 0%, where M is AI 8.7% or less, Ti 4.3% or less,
V 8.7% or less, Cr 8.3'X or less,
Hn 8.0% or less, Zr 5.5% or less,
Hf 5.0% or less, Nb 12.4% or less, Ta 10.3% or less, Mo 8.7$
below. Ge 5.7% or less, sb 2.4z or less,
When two or more elements are included: Sn 3.5% or less, Bi 4.13% or less, Ni 4.3% or less, and W 8.8% or less, the M combination is the atomic percentage of the one with the maximum value among the added elements. Ingredients F
), and the balance is Fe and impurity force 1 unavoidable in manufacturing, and the magnetically isotropic sintered body permanent magnet has an average crystal grain size of about 1 to IOCI-m. (4) 10 to 25% R in atomic percentage (where R is at least one kind of rare earth element including Y), 3 to 23% (1
) B, 50% or less (excluding Ca 0%)
, a predetermined percentage of one or two additive elements M (excluding M 0%, where M is A1 8.7% or less, Ti 4.3% or less, V 8.7% or less,
Cr 8.3% or more, Mn 8.0% or less, Zr 5.5% or less, 'If
5.0% or less, Nb 12.4% or less, Ta
10.3% or more, Mo 8.7% or less, G
e 5.7% or less, Sb 2.4% or less, S
n 3.5% or less, Bi 4.8% or more, N
i 4.3% or less, and W 8.8% or less), a specified percentage of one or more elements A (however, A
Except for OX, A is. , 3.3% or less, 3 2.5y6 or less, C4,O
X or less, and P 3.3X or less), provided that the content of M and A is not more than the atomic percentage of the element having the maximum value among the M and A elements contained, and the balance is Fe.
and a magnetically isotropic sintered permanent magnet comprising impurities unavoidable during manufacturing, the sintered body having an average crystal grain size of about 1 to +004 rn. (5) R of 10 to 25X in atomic percentage (where R is at least one kind of rare earth element including Y), 3 to 23% (
7) B, 50% or less (excluding LCo O%), one or more types of additive elements M (excluding M 0%, here M is AI 8.7) %
Below, Ti: 4.3% or less, V: 8.7% or less, Or: 8.3% or less. Mn 8.0% or less, Zr 5.5% or less,
Hf 5.0% or less, Nb i2.4% or less, Ta 10.3% or less, Mo 8.7% or less, G25.7% or less, Sb 2.4%
Below, Sn 3.5% or more, Bi 4.8%
Hereinafter, if Ni is 4.3% or less and W is 8.8% or less, and two or more types are included, the total M content is the atomic percentage or less of the one with the maximum value among the added elements), and the remainder is Fe and unavoidable in manufacturing. 1. A method for producing a magnetically homogeneous sintered permanent magnet, which comprises pressurizing and sintering an alloy powder containing impurities. (6) 10 to 25% R (R is at least one of the sumo elements including Y), 3 to 23% [7
) B, 50% or more% or less) Go (excluding LCO 0%),
A predetermined percentage of one or two types of additive elements M-L (however,
Except for M 0%, where M is AI 8.72;
Below, Ti 4.3% or less, V 8.7% or less, Cr 8.3% or less, Mn 8.0% or less, Zr 5.5% or less, Hf 5.0% or less, Nb 12.4X or less , Ta 10.3
% or less, Mo 8.7% or more, Ge 5.7
% or less, Sb 2.4% or more, Sn 3.
5% or less, Bi 4.8% or less, Ni 4.
3X or less, and 8,8z or less), a specified percentage of one or more types of element A (however, A
Except for OX, A is Cu 3.3% or less, 9 2.5% or less, C4
, 0% or less, and P 3.3% or less), the total amount of M and A is less than the atomic percentage of the element containing M and A that has the maximum 1α, and the balance is Fe and manufacturing A method for producing a magnetically isotropic sintered permanent magnet, which comprises pressurizing and sintering an alloy powder containing unavoidable impurities.