JPS627830A - Manufacture of permanent magnet material - Google Patents

Abstract

PURPOSE:To manufacture a permanent magnet material having superior magnetic characteristics at a low cost by blending the oxide of a rare earth element with iron powder and pure boron powder, ferroboron powder or boron oxide so as to obtain a specified composition and by subjecting the mixture to reduction with Ca and diffusion under specified conditions and to specified processing and treatment. CONSTITUTION:The oxide of at least one kind of rare earth element is blended with iron powder and at least one among pure boron powder, ferroboron powder, boron oxide and boride so as to obtain a composition consisting essentially of, by atom, 12-20% R (R is at least one among Nd, Pr, Dy, Ho and Tb combined optionally with at least one among la, Ce, Sm, Gd, Er, Eu, Tm, Yb and Y), 4-20% B, 0.05-3.0% boride and 65-81% Fe. The powdery mixture is subjected to reduction with Ca and diffusion by heat to 900-1,200 deg.C in an inert gaseous atmosphere and the resulting reaction product is put in water and slurrified. This slurry is treated with water and the treated starting material is pulverized, pressed, sintered and aged to obtain an Fe-B-R type permanent magnet material having a tetragonal phase as the principal phase.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application The present invention relates to a method for manufacturing FeB-R permanent magnet materials, and a Ca reduction method that allows a predetermined particle size to be obtained without melting or mechanical pulverization, and that can be easily manufactured. The present invention relates to a method for producing a permanent magnet material that has excellent magnetic properties using a raw material powder that is obtained by using a raw material powder that contains less impurities such as oxygen that degrades the magnetic properties of the final product.

BACKGROUND ART Current typical permanent magnet materials are alnico, hard ferrite and rare earth cobalt magnets.

Among these, rare earth cobalt magnets have extremely excellent magnetic properties and are used for a variety of purposes, but the main components, 5TII and Co, are both scarce in terms of resources and expensive, so they will not last for a long time. , it is difficult to stably supply it in large quantities. Therefore, there has been a strong need for a permanent magnet material that has excellent magnetic properties, is inexpensive, has abundant resources, and has constituent elements that can be stably supplied in the future.

The present applicant previously proposed an Fa-B-R system (at least one rare earth element including R4, tY) permanent magnet as a new high-performance permanent magnet that does not contain expensive Sm (Japanese Patent Application Laid-Open No. 59-1993). -46008@, JP-A-59-64733
@, JP-A-59-89401, JP-A-59-1321
No. 04).

This permanent magnet is made of natural resources such as ceramics and circles as R.
Using abundant light rare earths, 25MGO with FB as the main component
It is an excellent permanent magnet that exhibits an extremely high energy product exceeding s.

In general, Fs-BR permanent magnets use as starting materials rare earth metals with a purity of 99.5% or more obtained by electrolysis or thermal reduction, electric field iron with a purity of 99.9% or more, and low impurities such as boron. Expensive metal blocks are used.

The electrolytic iron with a purity of 99.9% and rare earth metals with a purity of 99.7% or more used as the above starting materials are high quality products with few impurities that have been refined from ores in advance, and are melted using high frequency. Thereafter, the ingot was roughly pulverized, then finely pulverized using a ball mill, etc., pressed, for example, while oriented in a magnetic field, roughly sintered, aged, and magnetized.

Therefore, raw materials of rare earth metals! ! ! For construction, advanced minute m
This method requires refining technology and is expensive, and the production of magnets by the above-mentioned ingot crushing method requires multiple steps, which increases the price of permanent magnets.

On the other hand, as a method for producing alloy powder for rare earth magnets in order to provide even higher magnetic properties to this F@B R-based permanent magnet and to produce it at low cost, the applicant has previously developed a production method using a Ca reduction method. (Japanese Unexamined Patent Publication No. 59-219404) and proposed a method for producing alloy powder for rare earth magnets by Ca reduction with roughly reduced oxygen, carbon, and calcium content (Japanese Patent Application No. 59-182574, Gansho 59-248
No. 798).

The gist is that R (R is Na, Pr, Dy, Ho,
At least one of To or furthermore, La,
Ce, Sm.

Cb, Er, EDy, Tm, Yb, La,
consisting of at least one type of Y) 12.5 atomic % to 2
0 atomic%, B4 atomic% ~ 20 atomic%, Fe 80 atomic% ~
At least one rare earth oxide and iron powder so that the content is 83 atomic %.

The amount of oxygen contained in the raw material powder such as the rare earth oxide in a mixed powder in which at least one of pure boron powder, ferroboron powder, and boron oxide, or an alloy powder or mixed oxide of the above constituent elements is blended into the above composition. 1.5 to 3.5 times the stoichiometrically required amount (weight ratio) of metal Ca and rare earth oxide Iwt% to 15W [% CaCjz were mixed, and 900% CaCjz was mixed in an inert gas atmosphere. Rare earths that perform reduction diffusion at ℃~1200℃, put the obtained reaction product in water to form a slurry, and roughly process the slurry with water! a
This is a method for producing alloy powder for stone.

By the above method, under the recovery of oxygen amount 60001), carbon ffi 11000pp or less, Ca amount 2000pp
FB-BR permanent magnet alloy powder with a diameter of less than Compared to permanent magnets, permanent magnets manufactured using alloy powders produced by Ca reduction have a problem in that crystal grains tend to grow during sintering, making it difficult to obtain excellent coercive force (■Hc).

Purpose of the Invention The present invention is directed to the production of Fa-B-R permanent magnets using alloy powder for rare earth magnets by Ca reduction method, which can reduce the price of Fa-B-R permanent magnets and improve magnetic properties. The object of the present invention is to provide a manufacturing method that prevents the growth of crystal grains during sintering and provides an Fs-BR-based permanent magnet material having excellent magnetic properties.

Structure and effect of the invention A permanent magnet manufactured using alloy powder by Ca reduction,
Grain growth occurs easily during sintering, and excellent coercive force
The reason why it is difficult to obtain Hc is that a nonmagnetic M-rich phase tends to form on the surface of the alloy powder, and therefore, when it is magnetized, crystal grains in the magnet body tend to grow, and the coercive force l1-f
This is considered to cause deterioration of c.

The inventors investigated various methods for manufacturing Fa-BR permanent magnet materials that prevent the growth of crystal grains during sintering and provide excellent magnetic properties.
This invention was completed based on the finding that the growth of crystal grains in a sintered magnet can be prevented by containing a specific amount of at least one type of boride such as No. 2 or BN.

That is, this invention provides R (R is at least one of Nd, Pr, Dy, Ho, To or furthermore, La, Ce, Sm
, (A, Er, EDy, Dingm.

consisting of at least one of Yb, La, Y)1
2 atomic% to 20 atomic%, B4 @ 20 atomic%, boride 0.05 atomic% to 3.0 atomic% Fe65 atomic%
At least one of the rare earth oxides, at least one of iron powder, pure boron powder, ferroboron powder, and boron oxide, and at least one of boride, so that ~81 atomic % is the main component. , or roughly blend the above-mentioned groove forming element alloy powder or mixed oxide into the above composition, and heat the mixed powder at 900°C to 120°C in an inert gas atmosphere.
Heating to 0° C. to perform Ca reduction and diffusion, the obtained reaction product was poured into water to form a slurry, the slurry was roughly treated with water, and the obtained treated raw material was pulverized,
This is a method for producing a permanent magnet material, which is characterized in that the permanent magnet material is obtained by performing pressing, pressing, sintering, and aging treatment to obtain a permanent magnet material having the above-mentioned composition as a main component and having a main phase of a tetragonal phase.

In addition, Ca reduction diffusion is preferably carried out using metal Ca and rare earth oxide in an amount of 1.5 to 3.5 times the chemically required amount of oxygen contained in the raw material powder such as the rare earth oxide. 1wt% to 5wt% of CaCR2 is mixed and heated to 900°C to 1200°C in an inert gas atmosphere to perform reduction diffusion, and the resulting reaction product is poured into water to form a slurry. It is preferable that the slurry is treated with water, and the resulting treated raw material is pulverized, then pressed, sintered, and aged to form a permanent magnet.

The alloy powder according to the present invention can be used as an intermediate raw material in the preliminary stage of producing rare earth metals, that is, inexpensive light rare earth oxides such as Ncj203 and Pr6011, and To304
Heavy rare earth oxides such as 203 and Fa powder.

Using at least one of pure boron powder (crystalline or amorphous), boron oxide such as Fe B powder or B2O3 powder, and boride as a starting material, metal Ca as a reducing agent, and a reduction reaction product. Because it is manufactured using CaC,h, which facilitates the disintegration of objects, and a process of reducing and diffusing Ca, it is cheaper and of higher quality than using various metal lump raw materials, and the magnetic characteristics of Fa-B-R permanent magnets are It is also ideal for industrial mass production.

The rare earth alloy powder according to the present invention can be used to obtain a permanent magnet by a powder metallurgy manufacturing method in which it is pulverized as it is, press molded, sintered and subjected to two aging treatments, and a rare earth metal lump, Compared to the ingot crushing method, which uses raw material ingots such as iron and boron as raw materials, raw material melting and casting.

It is possible to omit manufacturing processes that require time and cost, such as coarse pulverization, and as mentioned above, since inexpensive starting materials such as rare earth oxides are used, the price of permanent magnets is low,
In addition, by adding boride, it has the advantage that Fe-El-R permanent magnets with 16-stone characteristics, which are equivalent to or better than the ingot crushing method, can be mass-produced at low cost.

The Fe BR permanent magnet according to the present invention has (B
H) maX 20HGOe or more, iHc 10 ko
It has magnetic properties of e or higher, and can be used in a sufficiently stable manner even in an atmosphere at a temperature of room temperature or higher while maintaining these properties.

Reasons for Limiting the Invention The manufacturing process of the FeBR permanent magnet according to the present invention is as follows, and the reasons for the limitations will also be explained.

First, Nd oxide (Nd203-) and PT oxide (Pr
at least one light rare earth oxide such as Tb oxide (Tb304> or Dy oxide (Dy203));
Seeds, Fe powder, pure boron powder, ferroboron powder (Fe-8 powder).

At least one type of boron oxide such as B2O3 powder, and T12, BN, ZyBz, ZrB+2, HfB
z, VB2, NbB, FbEh, Taf3. T
aB2, CrB2, MoB, MoBz, VB2 B
SWBSW2 At least one kind of raw material powder of borides such as B, R12 atom% to 20 atom%, B44 atom to 20 atom%, boride 0.05 atom% to 3.0 atom% Fe65 atom%
~81 atomic% (here, R is at least one of m, Pr, ■, Tb, La, Ce, Sm,
Q:l, Er.

(consisting of at least one of EDy, Tm, yb, La, and Y) and, if necessary, metal powder and oxide powder (including mixed oxides with M4 constituents).

An additive element is added as an alloy powder (including mixed oxides with constituent elements) or other compound powder capable of returning Ca to form a raw material mixed powder.

In the present invention, when producing a Fe BR permanent magnet, 0.05 atomic % to 3.0 atomic % of TiBz and BN are added at the time of blending the raw material powder before Ca reduction.

ZrB2, ZrB+z, HFB2, VB2, Nb
B, NhBz, TaB, TaB2, CrB2, M
oBSMOE32, VB2 B-.

At least one raw material powder of borides such as WB and W2B is blended and mixed to perform Ca reduction and diffusion, but if the amount of boride is less than 0.05 at%, it will be difficult to sinter the magnet body. 3.0 at%
If the content exceeds 0.05 atomic % to 3.0 atomic %, the above effect will be saturated.

In this invention, in order to promote the reduction reaction with the rare earth oxide and the diffusion reaction with the raw material powder to proceed uniformly and sufficiently, and to obtain a homogeneous, single-phase alloy powder with a low oxygen content, Fe powder, pure boron powder, ferroboron powder,
At least one raw material powder or various additive elements of boron oxide such as B2O3 powder has a particle size of 150 Am.
Below, the particle size is preferably 75 μm or less.

Similarly, the average particle size of the rare earth oxide in the mixed powder is 1 to 10A.
m, and furthermore, the average particle size of the raw material powder is 1 to 51 Jms.
150. It is further preferable that it is 2 to 50 Bm.

Roughly, metallic Ca powder as a reducing agent for the rare earth element and CaCR2 powder for facilitating the disintegration of the reduction reaction product are added to the raw material mixed powder. The required amount of metallic Ca is
The amount of oxygen contained in raw material powders such as rare earth oxides is 1.5 to 3.5 times the stoichiometrically required amount, and CaC
l2 is Iwt% to 15wt% of the rare earth oxide.

Since the alloy powder according to the present invention contains B as an essential element, for example, the melting point of the raw material powder ferropolone powder is 100 to 400 degrees Celsius lower than that of iron powder, so the rare earth element during the reduction reaction However, if the amount of Ca added is less than 1.5 times the stoichiometric amount required to reduce the rare earth oxide used, the rare earth oxide is not sufficiently absorbed. Since it is not reduced, the alloy powder contains a large amount of oxygen, making it impossible to obtain a predetermined alloy powder composition.

On the other hand, Ca is a reaction byproduct produced during the reduction reaction.
O suppresses crystal grain growth during the reduction reaction of the alloy powder, thereby making it possible to obtain an alloy powder having a predetermined average grain size. However, an excess of Ca reducing agent exceeding 3.5 times the stoichiometric amount needed to reduce rare earth oxides not only increases the cost of the process but also , causing a radical exothermic reaction between CaO and H2O,
This is not preferable because the amount of oxygen in the resulting alloy powder increases.

In addition, the amount of residual Ca in the obtained alloy powder increases,
``For this reason, the magnetic properties of the manufactured permanent magnet will be low, so the upper limit is set at 3.5 times.

In addition, the rare earth oxide is sufficiently reduced, has a predetermined average particle size, has a low oxygen content, and has little residual Caff1.
In order to obtain magnet alloy powder having a predetermined composition with a good yield, the amount of the necessary reducing agent is 2 times the stoichiometric amount.
．． The most preferred case is 0 to 2.5 times.
, 1CaCf2 is 15w of rare earth element content
If the amount exceeds t%, when the reduction/diffusion reactant is treated with water at a specific temperature, the (J'-) in the water increases significantly, reacts with the generated rare earth alloy powder, and the amount of oxygen in the powder increases by 600%.
If it is 0 ppm or more, it cannot be used as an alloy powder for FeBR-based permanent magnets, and if it is less than 1 wt%, even if the reduction/diffusion reactant is put into the water, it will not disintegrate and cannot be treated with the water. Iwt% to 15wt%.

After the above-mentioned rare earth oxides, raw material powders such as Fe powders, and reducing agents are blended in predetermined amounts, they are mixed in an inert gas atmosphere using, for example, a type mixer.

Then, the mixed powder was heated for 90 minutes in an inert gas atmosphere.
The reduction/diffusion reaction is carried out for 0.5 to 5 hours in a temperature range of 0"C to 1200C. At this time, the temperature increase rate is set such that the adsorbed moisture gas component contained in the starting material 11 powder is removed. Therefore, the temperature is preferably 5°C/min or less.

Here, the reason why the reduction temperature was limited to 900°C to 1200°C is because below 900°C, the reduction of the rare earth oxide by Ca becomes insufficient and an alloy powder having a predetermined composition cannot be obtained. This is because the amount of oxygen contained in the powder increases, which is undesirable. Also, if the reduction temperature exceeds 1200°C, the diffusion reaction during reduction is promoted too much, causing crystal grain growth and reducing the predetermined average particle size. This is because an alloy powder having the above-mentioned properties cannot be obtained, and the amount of Ca remaining in the reaction product increases, which is not preferable as an alloy powder for permanent magnets. Furthermore, in order to obtain a high-performance permanent magnet alloy powder having a predetermined average particle size and component composition, and a low content of oxygen and residual Cam, a reduction temperature of 950° C. to 1100° C. is most desirable.

In the reduction/diffusion reaction by Ca, the molten rare earth metal reduced by Ca is immediately and homogeneously alloyed with Fe powder or Fe-B powder, and the alloy powder used is produced from the rare earth oxide with a good yield. It can be recovered.

After completion of the reduction/diffusion reaction, furnace cooling or rapid cooling may be performed to room temperature, but the cooling atmosphere is preferably an inert gas atmosphere so as not to oxidize the obtained alloy powder. It is also good to use the reaction product after crushing it in advance.

The obtained reduction reaction product is poured into water, and the reaction by-product CaO is reacted with H2O to form Ca(open)2, that is, the required stoichiometric amount of 1.5 to 3. The reduction reaction product obtained by blending 5 times as much reducing agent generates heat and spontaneously disintegrates into a slurry state in water, so it has the advantage of not requiring special mechanical pulverization. This slurry was thoroughly treated to remove Ca using water.
Furthermore, vacuum dry at i temperature and Fs of 10 to 500I.
BR alloy powder for permanent magnets is obtained.

Next, the above rare earth alloy powder is finely pulverized as it is,
Permanent magnets are manufactured using a powder metallurgy manufacturing method that includes press molding, sintering, and aging.

In addition, in this invention, the reaction products of reduction and diffusion bonding are slurried, and the treated water is treated with CI − and NO3” in the alloy powder, which are harmful to rare earth magnets.

It is preferable to use ion-exchanged water in order to remove anions such as CO3- and 5O4-, prevent oxidation of the powder, and prevent the formation of poorly soluble CaJi. In order to reduce the 02 concentration and the Ca concentration, it is preferable to cool the ion exchange water to 15°C or less.

The alloy powder according to the present invention obtained by the production method detailed above is composed of R (R is at least one of Fe, Pr, Dy, Ha, and Tb, or in addition, La, Ce, and Sm)
, Gci, Er, EDy, Tfll.

consisting of at least one of Yb, La, Y)1
2 atomic% to 20 atomic%, B44 atomic% to 20 atomic%, boride 0.05 atomic% to 3.0 atomic% Fe65 atomic%
The main component is ~81 atom%, the main phase is a tetragonal phase, the amount of oxygen contained is less than aoooopom, and the amount of carbon contained is 11000D.
0 or less, the Cai content is 2oooppm or less.

The oxygen contained in the alloy powder is undesirable because it combines with the most oxidizable rare earth element to form a rare earth oxide and remains in the permanent magnet as an oxide R2O3.If the oxygen content exceeds 6000 ppm, the coercive force is (c is 10
It becomes less than k○θ.

Furthermore, if the carbon content exceeds 1000p, the coercive force will significantly deteriorate, which is not preferable.

In addition, if the Ca content exceeds 2000 ppm, highly reducing Ca vapor will be generated in the winter melon during the subsequent sintering process during magnetization using this alloy powder, which will significantly damage the heat treatment furnace. It is undesirable because it lacks stability in industrial production and also increases the amount of residual Ca in the permanent magnet, deteriorating the magnetic properties.

Reasons for limiting the components of permanent magnets The rare earth element R in the rare earth alloy powder of the present invention accounts for 12 to 20 at % of the composition, including Nd and Pr.

At least one of Dy, Ho, Tb, or roughly, La, Co, Stn, Gd, Er, ED
y, Tl1l, Yb, La, and Y.

Also, normally one type of R is sufficient, but in practice two types are sufficient.
A mixture of more than one species (missile metal, didymium, etc.) can be used for reasons such as availability.

Incidentally, this 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.

R is an essential element in the new FaBR permanent magnet, and if it is less than 12 at%, the delivered structure will be α-
Because it has a cubic structure with the same structure as iron, high magnetic properties, especially high coercive force, cannot be obtained, and if it exceeds 20 atomic %, there will be a large amount of thick nonmagnetic phase, and the coercive force will be 10 koe or more, but , the residual magnetic flux density [3r decreases, and a permanent magnet with excellent characteristics cannot be obtained.

Therefore, the rare earth element is in the range of 12 atomic % to 20 atomic %.

B is an essential element in FsBR permanent magnets, and if it is less than 4 at%, the rhombohedral structure will be the main phase, and high coercive force iHC will not be obtained, and it will be less than 10 koe, and if it exceeds 20 at% , the B-rich nonmagnetic phase increases, the residual magnetic flux density 3r decreases, and (BH)max
It becomes less than 208 GOθ, and an excellent permanent magnet cannot be obtained. Therefore, B is in the range of 4 at.% to 20 at.%.

0.05 atomic % to 3.0 at least one type of boride
The reason why the content is atomic % is to suppress the growth of crystal grains during sintering of the magnet body, as described above.

Fe is an essential element in the new above-mentioned permanent magnet, and if it is less than 65 at%, the residual magnetic flux density Br decreases, and the
If it exceeds 1 atomic %, high coercive force cannot be obtained, so F
The content of e is 65 atomic % to 81 atomic %.

In addition, in the permanent magnet material according to the present invention, replacing a part of Fe with also can improve the temperature characteristics without impairing the magnetic properties of the obtained vii stone.
If the Co substitution amount exceeds 30% of Fe, the magnetic properties will deteriorate, which is undesirable, and the preferable substitution amount is 20% or less.

In addition to R, B, and Fe, the permanent magnet according to the present invention also includes
Although the presence of unavoidable impurities in industrial production can be tolerated, B
4.0 at% or less of C13, 5 at% or less of P
, 2.5 at% or less S, 1.5 at% or less CLL,
At least one type of SL of 5 at% or less, with a total of 5
．． By substituting at 0 atomic % or less, it is possible to improve the manufacturability of permanent magnets and reduce the cost.

In addition, at least one of the following additional elements is R-BF
It can be added to e-based permanent magnets because it is effective in improving the coercive force and squareness of the demagnetization curve, improving manufacturability, and reducing costs. However, addition to improve coercive force causes a decrease in residual magnetic flux density (Br), so it is desirable to add in a range that is equal to or higher than the residual magnetic flux density of conventional hard ferrite magnets.

5.0 at% or less Ti, 1.3.0 at% or less Ti, 5
．． 5 at% or less V, 4.5 at% or less Cr, 5.0
Mn of atomic % or less, Bi of 5.0 atomic % or less, 9.
Nb of 0 atomic% or less, Ta of 7.0 atomic% or less, 5
．． No less than 2 atom%, Oath less than 5.0 atom%, 1
．． sb of 0 atomic % or less, Ge of 3.5 atomic % or less.

Sn of 1.5 atomic % or less, 7'', 6 of 3.3 atomic % or less
．． 0 atomic % or less Ni, 1.1 atomic % or less Zn, 3.
Hf of 3 atomic % or less, at least one of the following is added.However, if two or more types are contained, the maximum content is 3 atomic % or less of the one having the maximum value among the added elements.
It becomes possible to increase the coercive force of permanent magnets. Particularly preferable additive elements are V and Nb.

angle, )to, W, Cr, M, the content is preferably a small amount, 3 atomic % or less is effective, /V is 0
．． The amount is 1 to 3 at%, preferably 0.2 to 2 at%.

These additive elements are added to the starting raw material mixed powder, such as metal powder, oxide, or alloy powder or mixed oxide with the constituent elements.
Alternatively, it can be added as a compound reducible with Ca.

In order to obtain a fine and uniform alloy powder capable of exhibiting high magnetic properties as a magnet, it is essential that the main phase (80% or more of a specific phase) of the crystalline phase be a square one. This magnetic phase is F
It is composed of sBR tetragonal compound crystals, and the grain boundaries are surrounded by a nonmagnetic layer. The nonmagnetic phase mainly consists of an R-rich phase, and if there is a large amount of B, a B-rich phase may also be partially present. The existence of grain boundary regions in the non-magnetic layer is considered to contribute to high properties and is an important structural feature of the alloy of the present invention, and even a small amount of solder is effective; for example, 1 vo 1% or more is sufficient. It is a large amount.

Furthermore, the permanent magnet of this invention can be press-molded in a field to obtain a magnetically anisotropic magnet, and by press-molded in a non-magnetic field, a magnetically isotropic magnet can be obtained. .

The permanent magnet according to the present invention has a coercive force iHc≧10kQe
, Zanuma magnetic flux density Br > 9 k (3), and the maximum energy product (BH) max is (BH) max ≧ 208 GOe in the most preferable composition range, and the maximum value is 30
Reach 8 GOe or more.

In addition, in the case where the main component of R in the alloy powder for permanent magnets of this invention is light rare earth metals mainly composed of porcelain and yen, R12 m % to 20 atomic %, B44 atomic % to 20 atomic %
When the main component is Fe 74 at% to 80 at%, it exhibits excellent magnetic properties of (BH)max 35HGOa or more, especially when the light rare earth metal is M.
The maximum value reaches 428 GOa or more.

Examples Example 1 Nd203 powder 174.3 j; 1D
ν203 powder 17.3 g.

Fe powder (particle size 150tim or less) 215.1
g Ferroboron powder 21.9 q (particle size 1
50. um or less, 19.58-Fs alloy powder) Ti B
2 powder 1.8g metallic Ca powder
162.90 (2.4 times the stoichiometric amount required for reduction) CaC,h powder 6.
Using a total amount of 7g (3.5wt% of rare earth oxide raw material) or more raw material powder of 6000, 30.5Nd −
3,6Dy-1,15B-0,5TiB2-64.
Aiming at 25 Fs (wt%), using a V-type mixer,
The mixture was mixed in an Ar gas atmosphere.

Next, the above-mentioned mixed powder was accelerated in a reduction-diffusion reaction at 1060° C. for 13.0 hours in an Ar gas atmosphere in a reduction furnace, and then cooled in the furnace to room temperature.

600 g of the obtained reduction reaction product was subjected to 6z io'c
After adding it to ion-exchanged water cooled to a slurry,
The slurry-like alloy powder was washed several times with ion-exchanged water cooled to 10° C., and dried under vacuum to obtain an alloy powder according to the present invention.

The obtained alloy powder has the following composition: Nd 30.4wt%, Dy 3.6wt%, B
1.09vt%, TLE320.5vt%, Fa
62.1wt%, 02 2500pDm, C490DDm, Ca
500ppm.

The particle size was 10 to 400 g.

This alloy powder was finely pulverized to obtain a finely pulverized powder with an average particle size of 2.8 mm, oriented in 10 K Oe, and pressure molded at 1.5 t4 to a size of 15 mm x 16 + nm x 10 mm. After that, it was heated at 1100°C for 2 hours in an Ar atmosphere.
Sintered under the conditions of 800°C in Ar
A two-stage aging treatment of 1 hour and 600°C x'1 hour was performed to give a permanent vi1'5.

The magnetic properties of the permanent magnets were measured and the results are shown in Table 1.

Also, for comparison, T, 82
An alloy powder was obtained by the manufacturing method under the above conditions except that no powder was blended, and this comparative alloy powder was roughly magnetized under the above conditions (Comparison 1), and its magnetic properties were measured. The results are shown in Table 1.

In addition, using alloy powder obtained from the ingot crushing method, 30.4
Nd-3,6Dy-1,09B-62,IFe(w
t%) composition was magnetized (
Comparison 2) and measured its magnetic properties. The results are shown in Table 1.

Table 1 Example 2 Nd 203 powder 170.0 (1~
203 powder 17.6 (], Fe powder (particle size 150Aim or less) 213.6 (] Ferroboron powder 24.5!11 (particle size 15
0Aim or less, 19.58-Fe alloy powder) BN powder
0.7 (1 metal Ca powder
166.1g (2.2g of the stoichiometric amount required for reduction)
5 times) CaC22 powder 7.5g (4.0wt% of rare earth oxide raw material) Using the above raw material powder total amount of 600g, 29.7Nd -
3,7Dy-1,3B-0,28N-65,IFe
(wt%) using a V-type mixer in an Ar gas atmosphere.

Next, the above-mentioned mixed powder was accelerated in a reduction-diffusion reaction at 1050° C. for 2.5 hours in an Ar gas atmosphere in a reduction furnace, and then cooled to room temperature in the furnace.

600 g of the obtained reduction reaction product was poured into ion-exchanged water cooled to 8°C in 6r1 to form a slurry. After washing twice, roughening and vacuum drying, 1 q of alloy powder according to the present invention was prepared.

The obtained alloy powder has the following composition: Nd 29.8wt%, Dso 3.7w
t%, B1゜25 wt%, EIN O, 2wt%
, Fa 63. owt%, 022400ppm, C4901) Om, Ca
500ppm.

Particle size was 20-4001M.

This alloy powder was finely pulverized to obtain a finely pulverized powder with an average particle size of 2.8 mm, oriented in a magnetic field of 10 KOa, pressure molded at 1.5 t4 to a size of 15 mm x 16 mm x 10 mm, and then Ar Sintered in an atmosphere at 1090°C for 2 hours, then sintered in Ar at 820°C for 1 hour.
Then, a two-stage aging treatment at 630°C x ltlr was performed to obtain a permanent magnet.

The magnetic properties of the obtained permanent magnet were measured, and the results are shown in Table 1.

In addition, for comparison, an alloy powder was obtained by the manufacturing method under the above conditions except that BN powder was not blended into the raw material powder before Ca reduction, and further magnetization (comparison) was performed using this comparative alloy powder under the above conditions. 3) and measured its magnetic properties. The results are shown in Table 1.

In addition, using alloy powder obtained from the ingot crushing method, 29.8
Nd-3,7Dy-1,25B-65,IFe(W
j%) composition was magnetized (
Comparison 4) and measured the magnetic properties. The results are shown in Table 1.

Table 2

Claims (1)

[Claims] R (R is at least one of Nd, Pr, Dy, Ho, Tb, or furthermore, La, Ce, Sm, Cd, E
r, Eu, Tm, Yb, La, Y) 12 atom% to 20 atom%, B4 atom% to 20 atom%, boride 0.05 atom% to 3.0 atom% Fe65 atom % to 81 atomic % as the main components, at least one of the rare earth oxides, at least one of iron powder, pure boron powder, ferroboron powder, and boron oxide, and at least one of boride. Seeds, or further alloy powders or mixed oxides of the above constituent elements are blended into the above composition, and this mixed powder is heated at 900°C to 120°C in an inert gas atmosphere.
Heating to 0° C. to perform Ca reduction and diffusion, the obtained reaction product was poured into water to form a slurry, the slurry was further treated with water, the obtained treated raw material was pulverized,
Pressed, sintered, and aged, Fe-
A method for producing a permanent magnet material, the method comprising obtaining a BR-based permanent magnet material.