JP2001085256A - PRODUCTION OF RARE-EARTH-Fe-Co-B MAGNET - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for produce a rare-earth-Fe-Co-B magnet having a superior magnetic characteristic without providing a demagnetizing step. SOLUTION: An R-Fe-Co-B alloy powder with a weak coersive force and residual hydrogen (R: at least one kind of rare-earth element including Y) which has a residual hydrogen of 0.01 to 0.5 wt.% and a coersive force of 0.01 to 8 kOe is oriented in a magnetic field, and it is molded by a press to form a green compact. Then the green compact is dehydrogenized at 700 to 900 deg.C in a vacuum atmosphere of 1 Torr or lower, and it is hot-pressed to form a rare-earth-Fe-Co-B magnet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION
Is at least one rare earth element containing Y), Fe and C
o and B as main components, and Ga, Zr,
Rare earth-Fe-Co having a composition containing at least one of Hf and, if necessary, at least one of Al and Si and having more excellent magnetic properties.
The present invention relates to a method for producing a B-based magnet.

[0002]

2. Description of the Related Art FIG. 4 is an explanatory view for explaining a method of manufacturing a conventional rare earth-Fe-Co-B-based magnet.
To manufacture a rare earth-Fe-Co-B based magnet, first,
R-Fe-Co- with or without homogenization
A B-based alloy ingot was prepared and this R-Fe-Co-B
As shown in FIG. 4, the system alloy ingot is subjected to a process of storing hydrogen by raising the temperature to 700 to 900 ° C. in a hydrogen atmosphere to store hydrogen (hereinafter, referred to as hydrogen storage process). During this hydrogen storage treatment, the R ₂ (Fe, Co) ₁₄ B phase becomes R
When the phase is transformed into three phases of H ₂ , Fe and (Fe, Co) ₂ B and subsequently dehydrogenated by sucking and holding it in a vacuum atmosphere of 1 Torr or less in the same temperature range, the hydrogen storage treatment is performed. RH generated by _2, Fe and (F
The three phases of e, Co) ₂ B are re-transformed into R ₂ (Fe, Co) ₁₄ B phase to form a fine recrystallized texture of R ₂ (Fe, Co) ₁₄ B intermetallic compound, and have excellent magnetic properties. [Japanese Unexamined Patent Publication (Kokai) No. 3-129702, Summary of General Lectures of the Autumn Meeting of the Japan Institute of Metals (1989, p. 36).
7) etc.]. This production method comprises the steps of hydrogenating and decomposing R ₂ Fe ₁₄ B intermetallic compound phase.
ition), dehydrogenation (Desorption) and recombination (Reco
mbination) is called the HDDR processing method.

[0003] The composition of the R-Fe-Co-B-based alloy is as follows:
0.1 to 50%, B: 3 to 20%, the balance being Fe
And the composition consisting of unavoidable impurities,
R: 10 to 20%, Co: 0.1 to 50%, B: 3 to 2
0%, and further contains one or more of Ga, Zr, and Hf: 0.001 to 5.0%, with the balance being Fe and unavoidable impurities. The alloy according to (i) or (b) further contains one or two of Al and Si in a total amount of 0.01 to 2.0%, and the remainder has a composition of Fe and unavoidable impurities.
It is also known that a Fe-Co-B alloy is preferable.

A rare earth-Fe-Co- alloy obtained by subjecting an R-Fe-Co-B alloy having these compositions to HDDR treatment.
As shown in FIG. 4, the B-based magnet powder is filled in a metal mold and press-formed while being oriented in a magnetic field to produce a green compact.
There is also known a method of manufacturing a rare earth-Fe-Co-B-based magnet by subjecting the compact to demagnetization treatment, removing the compact from a mold, and thereafter performing hot pressing.

[0005]

The rare-earth-Fe-Co-B-based magnet manufactured by the above-mentioned conventional method has excellent magnetic properties, but rare-earth-Fe-Co-B magnets having more excellent magnetic properties. There is a need for B-based magnets.

[0006]

Means for Solving the Problems Accordingly, the present inventors have
Research was conducted to obtain a rare earth-Fe-Co-B-based magnet having more excellent magnetic properties.
-In the manufacturing process of the Co-B based magnet powder, R-Fe-
Rare earth-Fe-Co-B-based alloy powder obtained by hydrogen-absorbing treatment in a Co-B-based alloy ingot is subjected to insufficient dehydrogenation treatment so that 0.01-0.5 wt% hydrogen remains and coercive force : Weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder having 0.01 to 8 kOe was prepared and pressed while orienting this weak coercive force hydrogen-retained R-Fe-Co-B-based alloy powder in a magnetic field. Rare earths obtained by hot pressing after dehydrogenation of molded green compact-
Research results have shown that the magnetic properties of the Fe-Co-B-based magnet are further improved than before.

The present invention has been made on the basis of the above research results, and (1) a weak coercive force having hydrogen: 0.01 to 0.5% by weight and a coercive force: 0.01 to 8 kOe. Producing hydrogen residual R-Fe-Co-B-based alloy powder,
Weak coercive force with low coercive force Hydrogen residual R-Fe-Co-B
The green alloy powder is press-formed while being oriented in a magnetic field to produce a green compact.
After performing a dehydrogenation treatment of maintaining a vacuum atmosphere equal to or lower than Torr, hot-pressing rare earth -Fe-Co-
The method is characterized by a method for manufacturing a B-based magnet.

The weak coercive force hydrogen residual R—Fe—Co—B alloy powder having 0.01 to 0.5% by weight of coercive force and 0.01 to 0.5 kOe of hydrogen is retained in the hydrogen-absorbed R-Fe—Co—B alloy powder. When the Fe-Co-B-based alloy powder is kept in an inert gas atmosphere for a long time (0.5 to 5 hours) and cooled, R-Fe-
The hydrogen content of the Co-B-based alloy powder can be reduced to 0.01 to 0.5% by weight. Therefore, the present invention provides (2) an R-Fe-Co-B-based alloy ingot in a mixed atmosphere of hydrogen or hydrogen and an inert gas at a temperature of 70:
By raising the temperature to 0 to 900 ° C and holding it, R-Fe-C
The o-B-based alloy ingot is subjected to a hydrogen storage treatment, followed by introducing an inert gas for a long time and cooling to room temperature to leave 0.01 to 0.5% by weight of hydrogen and coercive force:
Weak coercivity hydrogen residual R-Fe with 0.01-8 kOe
-Co-B-based alloy powder is produced, and this weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder is press-formed while being oriented in a magnetic field to produce a green compact. : 7
The method is characterized by a method for producing a rare earth-Fe-Co-B-based magnet which is subjected to a dehydrogenation treatment at a temperature of 00 to 900 ° C and a vacuum atmosphere of 1 Torr or less and then hot pressed.

The weak coercive force hydrogen-remaining R-Fe-Co-B alloy powder having 0.01 to 0.5% by weight of hydrogen and having a coercive force of 0.01 to 8 kOe is subjected to the hydrogen absorbing treatment. Temperature of the obtained R-Fe-Co-B-based alloy powder: 700-
It can be manufactured by performing incomplete dehydrogenation treatment at 900 ° C. by suction and holding until a vacuum atmosphere of more than 1 Torr and not more than 100 Torr and then introducing an inert gas and cooling to room temperature. Therefore, the present invention
(3) In an R-Fe-Co-B-based alloy ingot, in a mixed atmosphere of hydrogen or hydrogen and an inert gas, at a temperature of 700 to
By raising the temperature to 900 ° C. and holding it, R-Fe-Co-
The R-Fe-Co-B-based alloy powder is prepared by subjecting the B-based alloy ingot to a hydrogen-absorbing treatment for absorbing hydrogen, and then the hydrogen-absorbed R-Fe-Co-B-based alloy powder is heated to a temperature of 700 to 900 ℃, over 1 Torr and 100 To
After performing an incomplete dehydrogenation treatment of suction and holding until a vacuum atmosphere of rr or less, an inert gas is introduced and cooled to room temperature to leave 0.01 to 0.5% by weight of hydrogen and coercive force: A weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder having 0.01 to 8 kOe is prepared, and press-forming while orienting the weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder in a magnetic field. A green compact is prepared by subjecting the green compact to dehydrogenation treatment to a vacuum atmosphere at a temperature of 700 to 900 ° C. and 1 Torr or less, and then hot-pressing a rare-earth-Fe—Co—B-based magnet. Manufacturing method.

Further, the weak residual coercive force hydrogen-retained R-Fe-Co-B alloy powder having 0.01 to 0.5% by weight of coercive force and 0.01 to 0.5 kOe of hydrogen remaining therein is subjected to a hydrogen absorbing treatment. The obtained R-Fe-Co-B alloy powder was heated to a temperature of 700.
９００900 ° C., dehydrogenation treatment by suction-holding until a vacuum atmosphere of 1 Torr or less, sufficiently dehydrogenation, introduction of an inert gas, cooling to room temperature, and then room temperature
It can be manufactured by performing low-temperature hydrogen absorption treatment in a hydrogen atmosphere at 400 ° C. Therefore, the present invention provides (4) an R—Fe—Co—B-based alloy ingot in a mixed atmosphere of hydrogen or hydrogen and an inert gas at a temperature of 70:
By raising the temperature to 0 to 900 ° C and holding it, R-Fe-C
The o-B-based alloy ingot is subjected to a hydrogen-absorbing treatment for absorbing hydrogen to produce an R-Fe-Co-B-based alloy powder, and then the hydrogen-absorbed R-Fe-Co-B-based alloy powder is heated to a temperature. : At 700 to 900 ° C., a dehydrogenation process of suction and holding until a vacuum atmosphere of 1 Torr or less is performed, and then an inert gas is introduced and cooled to room temperature.
-Fe-Co-B-based alloy magnet powder was prepared and this RF
The e-Co-B-based alloy magnet powder is subjected to a low-temperature hydrogen absorption treatment in which the magnet powder is kept in a hydrogen atmosphere at room temperature to 400 ° C. to obtain hydrogen:
Coercive force: 0.01 to 0.5% by weight remaining: 0.01 to 8
A weak coercive hydrogen residual R-Fe-Co-B-based alloy powder having kOe is prepared, and the weak coercive hydrogen residual R-Fe-C
The OB alloy powder is press-formed while being oriented in a magnetic field to produce a green compact, and the green compact is heated at a temperature of 700 to 900.
C. After performing dehydrogenation treatment until a vacuum atmosphere of 1 Torr or less is reached, hot-pressed rare earth-Fe-Co-B
The method is characterized by a method of manufacturing a system magnet.

The R-Fe-Co-B alloy ingot used in the present invention can be subjected to a homogenization treatment by maintaining the temperature in a vacuum or an Ar atmosphere at a temperature of 600 to 1200 ° C. before hydrogen absorption treatment. More preferred. Therefore, the present invention provides (5) the above-mentioned R-Fe-Co-B-based alloy ingot, which is prepared in a vacuum or Ar atmosphere at a temperature of 600;
The method for producing a rare-earth-Fe-Co-B-based magnet according to the above (2), (3) or (4), wherein the homogenization treatment is performed by maintaining the temperature at -1200 ° C. is there.

It is preferable that the alloy has the component composition shown in (i) to (). Therefore, the present invention
(6) The R-Fe-Co-B-based alloy is expressed in atomic%,
R: 10 to 20%, Co: 0.1 to 50%, B: 3 to 2
Production of the rare earth-Fe-Co-B-based magnet according to the above (1), (2), (3), (4) or (5), wherein the magnet contains 0% and the balance consists of Fe and unavoidable impurities. Method, (7) the R-Fe-Co-B-based alloy contains
R: 10 to 20%, Co: 0.1 to 50%, B: 3
-20%, and further contains one or more of Ga, Zr, and Hf: 0.001-5.0%, with the balance having a composition consisting of Fe and unavoidable impurities. 1), (2), (3), (4) or (5), the method for producing a rare earth-Fe-Co-B-based magnet, (8)
The R-Fe-Co-B alloy has an atomic percentage of R: 10
-20%, Co: 0.1-50%, B: 3-20%, and one or more of Ga, Zr, and Hf: 0.001-5.0%. Containing, and A
1, or two of Si, from 0.01 to 2.
(1), (2), (3), (4) or (5), wherein the rare-earth-Fe-Co-B-based magnet has a composition of 0% and the balance of Fe and unavoidable impurities. (9) The R-Fe-Co-B-based alloy has an atomic percentage of
R: 10 to 20%, Co: 0.1 to 50%, B: 3
(1) having a composition containing 0.01 to 2.0% in total of one or two of Al and Si, and a balance of Fe and unavoidable impurities.
Rare earth-F described in (2), (3), (4) or (5)
a method of manufacturing an e-Co-B-based magnet.

As described above, the rare earth-Fe-
According to the method of manufacturing a Co-B based magnet, it is possible to manufacture a rare earth-Fe-Co-B based magnet which is more excellent than the conventional one.
According to the method for producing a -B-based magnet, the magnet has the following excellent effects. That is, the conventional rare earth -Fe-Co-
B-based magnet powder has an extremely large coercive force,
In order to demagnetize the green compact produced by press molding while orienting in the magnetic field, a large-scale demagnetizing device is required, and the equipment cost is high, and the cost is high. Insufficient demagnetization using a low demagnetizer requires a great deal of effort to remove the green compact from the mold, and in the worst case, breaks the molded green compact during removal work However, according to the method for manufacturing a rare earth-Fe-Co-B-based magnet of the present invention, first, an R-Fe-Co-B-based alloy ingot is obtained by performing a hydrogen storage treatment. Rare earth -Fe-Co-
Insufficient dehydrogenation treatment of the B-based alloy powder leaves 0.01-0.5 wt% hydrogen, and the coercive force: 0.01
Coercivity Hydrogen Residual R-Fe-Co- with ~ 8 kOe
A B-based alloy powder is prepared, and this weak coercive force hydrogen residual R-Fe
When the -Co-B-based alloy powder is used, this weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder can be sufficiently oriented even in a not so large magnetic field (about 15 kOe) from a place where the coercive force is weak. , This weak coercive force hydrogen residual R-
A green compact produced by press-forming the Fe-Co-B-based alloy powder while orienting it in a magnetic field can be easily taken out of the mold without demagnetizing treatment, and therefore, the demagnetizing treatment step can be omitted. Therefore, a rare-earth-Fe-Co-B-based magnet having excellent magnetic properties can be manufactured more efficiently.

Next, the rare earth-Fe-Co-
The manufacturing process of the B-based magnet will be specifically described with reference to the drawings. FIG. 1 shows the rare earth-Fe-C of (2) of the present invention.
It is explanatory drawing which shows the manufacturing method of an oB system magnet. The R-Fe-Co-B alloy ingot subjected to homogenization treatment or not homogenization treatment is heated to a temperature of 700 to 900 ° C in an atmosphere of hydrogen or a mixed atmosphere of hydrogen and an inert gas to thereby maintain the R-Fe. -Co-B-based alloy ingot is subjected to a hydrogen-absorbing treatment for absorbing hydrogen to produce an R-Fe-Co-B-based alloy powder, and the hydrogen-absorbed R-Fe-Co
When the -B-based alloy powder is kept in an inert gas atmosphere for a long time and cooled to room temperature, it is dehydrogenated during cooling, and hydrogen: 0.
Coercive force: 0.01 to 8 kO with 01 to 0.5% by weight remaining
e, a weak coercive force hydrogen residual R-Fe-Co-B-based alloy powder is generated. In FIG. 1, the dehydrogenation treatment is performed with an inert gas
(Preferably Ar gas),
It is necessary to introduce the inert gas for a long time (0.5 to 5 hours). The thus obtained weak coercive force hydrogen residual R-Fe-Co-B-based alloy powder having a low coercive force is filled in a mold,
Press molding while orientation in a magnetic field to produce a green compact,
Next, the green compact is removed from the mold. At this time, since the coercive force of the green compact is weak, the green compact can be easily removed from the mold without demagnetization. The green compact is heated at a temperature of 70
R-Fe-Co-B having excellent magnetic properties is obtained by performing hot-pressing after performing dehydrogenation by suction-holding until a vacuum atmosphere of 0 to 900 ° C and 1 Torr or less is obtained.
A system magnet can be made.

FIG. 2 shows the rare earth of the above (3) of the present invention.
It is explanatory drawing which shows the manufacturing method of a Fe-Co-B type magnet.
R-Fe-Co- with or without homogenization
A hydrogen storage treatment in which the R-Fe-Co-B-based alloy ingot stores hydrogen by raising the temperature of the B-based alloy ingot to 700 to 900 ° C in an atmosphere of hydrogen or a mixture of hydrogen and an inert gas. And then continuously at a temperature of 700 to 900 ° C., exceeding 1 Torr and 100 To
After performing incomplete dehydrogenation treatment by suction and holding until a vacuum atmosphere of rr or less is reached, by introducing an inert gas and cooling to room temperature, 0.01 to 0.5% by weight of hydrogen is retained and retained. A weak coercive force hydrogen residual R-Fe-Co-B-based alloy powder having a magnetic force of 0.01 to 8 kOe is obtained.

In FIG. 2, more than 1 Torr and 100 Torr
Since the incomplete dehydrogenation process of suction and holding is performed until the vacuum atmosphere becomes equal to or less than r, hydrogen: 0.01 more efficiently than in FIG.
A weak coercive force hydrogen residual R-Fe-Co-B-based alloy powder having a coercive force of 0.01 to 8 kOe remaining with a content of about 0.5% by weight is obtained. The thus obtained weak coercive force hydrogen-remaining R-Fe-Co-B-based alloy powder is filled in a mold, and press-formed while being oriented in a magnetic field to produce a green compact. Is removed from the mold. At this time, since the coercive force of the green compact is weak, the green compact can be easily removed from the mold without demagnetization. The green compact is heated at a temperature of 700 to 90.
After performing dehydrogenation treatment by suction and holding in a vacuum atmosphere at 0 ° C. and 1 Torr or less, an R—Fe—Co—B-based magnet having excellent magnetic properties can be produced by hot pressing.

FIG. 3 shows the rare earth of (4) of the present invention.
It is explanatory drawing which shows the manufacturing method of a Fe-Co-B type magnet.
R-Fe-Co with or without homogenization
The R-Fe-Co-B-based alloy ingot is subjected to a hydrogen occlusion treatment by raising and maintaining the temperature of the B-based alloy ingot to 700 to 900 ° C in a mixed atmosphere of hydrogen or hydrogen and an inert gas, Then temperature: 700-900
C., and sufficiently dehydrogenated by suction and holding until a vacuum atmosphere of 1 Torr or less is obtained. Then, an inert gas is introduced and cooled to room temperature, and then maintained at a temperature in the range of room temperature to 400 ° C. By performing a low-temperature hydrogen absorption treatment for absorbing a small amount of hydrogen, a weak coercive force hydrogen residual R-Fe-Co- having 0.01 to 0.5% by weight of hydrogen and having a coercive force of 0.01 to 8 kOe remains. A B-based alloy powder is produced.

In FIG. 3, after the hydrogen storage treatment, the temperature is maintained at 700 to 900 ° C. and the atmosphere is reduced to a vacuum atmosphere of 1 Torr or less, and the dehydrogenation treatment is sufficiently performed. Cooling. The R-Fe-Co-B-based alloy powder thus obtained has a large coercive force since it has been sufficiently dehydrogenated.
It is not preferable to fill the mold with the o-B-based alloy powder and press-mold it while orienting it in a magnetic field to produce a green compact because a large force is required when removing the green compact from the mold. Therefore, in the present invention, the dehydrogenated RF
The e-Co-B-based alloy powder is further subjected to a low-temperature hydrogen absorption treatment in a hydrogen atmosphere at a temperature in the range of room temperature to 400 ° C. to lower the coercive force. The low-temperature hydrogen absorption treatment is performed at room temperature to 400 ° C. so that the R ₂ (Fe, Co) ₁₄ B phase is not transformed into the three phases of RH ₂ , Fe and (Fe, Co) ₂ B. Temperature must be maintained. The thus obtained weak coercive force hydrogen residual RF
A green compact is prepared while orienting the e-Co-B-based alloy powder in a magnetic field, and then the green compact is removed from the mold. At this time, since the coercive force of the green compact is weak, the green compact can be easily removed from the mold without demagnetization. This green compact is suction-held in a vacuum atmosphere at a temperature of 700 to 900 ° C. and 1 Torr or less to sufficiently perform dehydrogenation treatment, and then hot pressed to obtain R-Fe—C having excellent magnetic properties.
An oB-based magnet can be made. The temperature of the hot press is preferably from 600 to 900C.

Next, the reason why the component composition of the R-Fe-Co-B based anisotropic magnet of the present invention is limited as described above will be described. (A) RR is Nd, Pr, Tb, Dy, La, Ce, Ho, E
one or more of r, Eu, Sm, Gd, Tm, Yb, Lu, and Y, generally mainly Nd;
Although other rare earth elements are added to this, Dy and Pr have the effect of improving the coercive force iHc. If the R content is lower than 10% or higher than 20%, the coercive force of the anisotropic magnet is reduced, and excellent magnetic properties cannot be obtained. Therefore, the content of R is 10 to 20%.
Determined.

(B) BB If the B content is less than 3% or more than 20%, the coercive force of the anisotropic magnet is reduced and excellent magnetic properties cannot be obtained. Was determined to be 3 to 20%. A part of B may be replaced with C, N, O, or F.

(C) Co The addition of Co improves the coercive force and magnetic temperature characteristics (eg, Curie point) of the anisotropic magnet, and further has the effect of improving the corrosion resistance. .1
If the content is less than 50%, the desired effect cannot be obtained. On the other hand, if the content exceeds 50%, the magnetic properties are rather deteriorated. Therefore, the content of Co is set to 0.1 to 50%. When the content of Co is between 0.1 and 20%, the coercive force becomes highest, so that it is more preferable that the content of Co be 0.1 to 20%.

(D) Ga, Zr and Hf These components are contained as components of the R-Fe-Co-B based anisotropic magnet to improve coercive force and to provide excellent magnetic anisotropy and corrosion resistance. It is added because it has a stabilizing effect, but the total of Ga and Zr, the total of Ga and Hf, or the total of Ga, Zr and Hf is 0.1%.
If it is less than 001%, the desired effect cannot be obtained, while 5.0
%, The magnetic properties deteriorate. Therefore, the sum of Ga and Zr, the sum of Ga and Hf, or the sum of Ga, Zr and Hf is 0.001 to 5.0.
%.

(E) Al and Si An R-Fe-Co-B-based alloy containing 0.001 to 5.0% of the total of Ga and Zr, the total of Ga and Hf, or the total of Ga, Zr and Hf. , Al and Si are added because the maximum energy product can be stably increased by adding one or more of them. However, if the content is less than 0.01%, the desired effect cannot be obtained. On the other hand, addition of more than 2.0% is not preferred because the value of magnetization cannot be increased. Therefore,
One or more of Al and Si are determined to be 0.01 to 2.0% in total.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION R-Fe
-Co-B based alloy ingots were prepared, and these alloy ingots were each placed in an argon gas atmosphere at a temperature of 112.
After homogenizing at 0 ° C for 40 hours, about 1 hour
Raw material alloys a to h having the component compositions shown in Table 1 were prepared by crushing to 0 mm square.

[0025]

[Table 1]

Examples 1 to 3 and Conventional Example 1 The raw material alloy a shown in Table 1 was heated from room temperature to a temperature of 800 ° C. in a hydrogen atmosphere at 1 atm and held at this temperature for 1 hour to perform a hydrogen absorbing treatment. After that, after performing the treatment under the conditions shown in Table 2, lightly crushed in a mortar to produce an R-Fe-Co-B-based alloy powder having an average particle size of 50 µm (hereinafter, referred to as alloy powder). The hydrogen concentration and the coercive force (iHc) of these alloy powders were measured.
It was shown to. The alloy powder obtained as described above was filled in a mold, and press-formed while being oriented in a magnetic field of 15 kOe to produce a green compact. The green compact was taken out of the mold. At this time, the green compacts of the alloy powders manufactured in Examples 1 to 3 could be easily taken out without performing the demagnetization treatment. Without magnetic treatment, it could not be removed from the mold. After the green compact of the alloy powder prepared in Examples 1 to 3 was taken out of the mold, the temperature was raised to 800 ° C. in Ar gas, and when the temperature reached 800 ° C., suction was performed until a vacuum atmosphere of 0.1 Torr or less was reached. Hold, followed by the introduction of Ar gas and quenching to dehydrogenate the green compact,
This dehydrogenated green compact is heated in an Ar gas atmosphere at a temperature of:
An anisotropic permanent magnet was obtained by hot pressing at 800 ° C. and 1.5 Ton / cm ² .

On the other hand, the compact of the alloy powder produced in Conventional Example 1 was demagnetized, taken out of the mold, and kept in an Ar gas atmosphere at a temperature of 800 ° C. and 1.5 Ton / c.
An anisotropic permanent magnet was obtained by hot pressing under the condition of m ² .

The green compact compacted in the magnetic field was hot-pressed while being arranged so that the orientation direction coincided with the pressing direction at the time of hot pressing. All of the anisotropic permanent magnets thus obtained had a density of 7.5 to 7.7 g / cm ^{3 and} were sufficiently dense. Table 2 shows the magnetic properties of the anisotropic permanent magnets obtained in Examples 1 to 3 and Conventional Example 1.

[0029]

[Table 2]

From the results shown in Table 2, the anisotropic permanent magnets manufactured in Examples 1 to 3 have a maximum energy product compared to the anisotropic permanent magnet manufactured in Conventional Example 1 using the same raw material alloy a. (BHmax), the production method of the present invention provides a rare earth-Fe-C
It can be seen that an oB-based magnet can be provided.

Examples 4 to 6 and Conventional Example 2 The raw material alloy b shown in Table 1 was heated from room temperature to a temperature of 810 ° C. in a hydrogen atmosphere of 1 atm and held at this temperature for 1 hour to perform a hydrogen absorbing treatment. After that, the powder was treated under the conditions shown in Table 3 and lightly crushed in a mortar to produce alloy powder having an average particle size of 50 μm. The hydrogen concentration and coercive force (iHc) of these alloy powders were measured. Table 3 shows the results.

The alloy powder obtained as described above was filled in a mold, and press-formed while being oriented in a magnetic field of 15 kOe to produce a green compact. The green compact was taken out of the mold. At this time, the green compacts of the alloy powders manufactured in Examples 4 to 6 could be easily taken out without performing demagnetization treatment. Without magnetic treatment, it could not be removed from the mold. The green compact of the alloy powder produced in Examples 4 to 6 was taken out of the mold, heated to 810 ° C. in Ar gas, and when it reached 810 ° C., sucked until a vacuum atmosphere of 0.1 Torr or less was reached. Then, the compact was dehydrogenated by introducing and quenching Ar gas, and the compact thus dehydrogenated was placed in an Ar gas atmosphere at a temperature of 810 ° C. and 1.5 Ton / cm ^2. The anisotropic permanent magnet was obtained by hot pressing under the following conditions.

On the other hand, the green compact of the alloy powder produced in Conventional Example 2 was demagnetized, taken out of the mold, and kept in an Ar gas atmosphere at a temperature of 810 ° C. and 1.5 Ton / c.
An anisotropic permanent magnet was obtained by hot pressing under the condition of m ² .

The green compact formed in a magnetic field was hot-pressed by arranging so that the orientation direction coincided with the pressing direction at the time of hot pressing. All of the anisotropic permanent magnets thus obtained had a density of 7.5 to 7.7 g / cm ^{3 and} were sufficiently dense. Table 3 shows the magnetic properties of the anisotropic permanent magnets obtained in Examples 4 to 6 and Conventional Example 2.

[0035]

[Table 3]

From the results shown in Table 3, it can be seen that the anisotropic permanent magnets manufactured in Examples 4 to 6 have a maximum energy product compared to the anisotropic permanent magnet manufactured in Conventional Example 2 using the same raw material alloy b. (BHmax), the production method of the present invention provides a rare earth-Fe-C
It can be seen that an oB-based magnet can be provided.

Examples 7 to 9 and Conventional Example 3 The raw material alloy c shown in Table 1 was heated from room temperature to a temperature of 820 ° C. in a hydrogen atmosphere of 1 atm and kept at this temperature for 3 hours to perform a hydrogen absorbing treatment. After that, the alloy was treated under the conditions shown in Table 4 and crushed lightly in a mortar to produce alloy powder having an average particle size of 50 μm. The hydrogen concentration and coercive force (iHc) of these alloy powders were measured. Table 4 shows the results.

The alloy powder thus obtained was filled in a metal mold, and press-molded while being oriented in a magnetic field of 15 kOe to produce a green compact. Thereafter, the green compact was taken out of the metal mold. At this time, the green compacts of the alloy powders manufactured in Examples 7 to 9 could be easily taken out without performing demagnetization treatment. Without magnetic treatment, it could not be removed from the mold. The alloy powder compacts prepared in Examples 7 to 9 were taken out of the mold, heated to 820 ° C. in Ar gas, and when the temperature reached 820 ° C., sucked until a vacuum atmosphere of 0.1 Torr or less was reached. Then, the compact was subjected to dehydrogenation treatment by introducing and quenching Ar gas, and the compact thus dehydrogenated was placed in an Ar gas atmosphere at a temperature of 820 ° C. and 1.5 Ton / cm ^2. The anisotropic permanent magnet was obtained by hot pressing under the following conditions.

On the other hand, the compact of the alloy powder produced in Conventional Example 3 was demagnetized, taken out of the mold, and kept in an Ar gas atmosphere at a temperature of 820 ° C. and 1.5 Ton / c.
An anisotropic permanent magnet was obtained by hot pressing under the condition of m ² .

The green compact compacted in the magnetic field was hot-pressed while being arranged so that the orientation direction coincided with the pressing direction at the time of hot pressing. All of the anisotropic permanent magnets thus obtained had a density of 7.5 to 7.7 g / cm ^{3 and} were sufficiently dense. Table 4 shows the magnetic properties of the anisotropic permanent magnets obtained in Examples 7 to 9 and Conventional Example 3.

[0041]

[Table 4]

From the results shown in Table 4, it can be seen that the anisotropic permanent magnets manufactured in Examples 7 to 9 have the maximum energy product compared with the anisotropic permanent magnet manufactured in Conventional Example 3 using the same raw material alloy c. (BHmax), the production method of the present invention provides a rare earth-Fe-C
It can be seen that an oB-based magnet can be provided.

Examples 10 to 12 and Conventional Example 4 The raw material alloy d shown in Table 1 was heated from room temperature to a temperature of 820 ° C. in a hydrogen atmosphere of 1 atm and kept at this temperature for 3 hours to perform a hydrogen absorbing treatment. After that, after the treatment under the conditions shown in Table 5, the powder was lightly crushed in a mortar to produce alloy powder having an average particle size of 50 μm, and the hydrogen concentration and coercive force (iHc) of these alloy powders were measured. Table 5 shows the results.

The alloy powder thus obtained was filled in a mold, and press-formed while being oriented in a magnetic field of 15 kOe to produce a green compact. The green compact was taken out of the mold. At this time, the green compact of the alloy powder prepared in Examples 10 to 12 could be easily taken out without performing demagnetization treatment. Without magnetic treatment, it could not be removed from the mold. The green compact of the alloy powder produced in Examples 10 to 12 was taken out of the mold and then placed in Ar gas.
When the temperature rises to 20 ° C and reaches 820 ° C, 0.1 Torr
Hold by suction until the following vacuum atmosphere is reached.
The green compact is dehydrogenated by introducing r gas and rapidly cooled, and the dehydrogenated green compact is hot-pressed in an Ar gas atmosphere at 820 ° C. and 1.5 Ton / cm ^2. Thus, an anisotropic permanent magnet was obtained.

On the other hand, the green compact of the alloy powder produced in Conventional Example 4 was demagnetized, taken out of the mold, and kept in an Ar gas atmosphere at a temperature of 820 ° C. and 1.5 Ton / c.
An anisotropic permanent magnet was obtained by hot pressing under the condition of m ² .

The green compact formed in a magnetic field was hot-pressed by arranging so that the orientation direction coincided with the pressing direction at the time of hot pressing. All of the anisotropic permanent magnets thus obtained had a density of 7.5 to 7.7 g / cm ^{3 and} were sufficiently dense. Examples 10 to 12 and Conventional Example 4
Table 5 shows the magnetic properties of the anisotropic permanent magnet obtained in the above.

[0047]

[Table 5]

From the results shown in Table 5, Examples 10-1
The anisotropic permanent magnet produced in Example 2 has superior magnetic properties as compared with the anisotropic permanent magnet produced in Conventional Example 4 using the same raw material alloy d. It can be seen that a rare earth-Fe-Co-B-based magnet can be provided that is even better.

Examples 13 to 15 and Conventional Example 5 An alloy powder was prepared in the same manner as in Examples 1 to 3 and Conventional Example 1 except that the raw material alloy e shown in Table 1 was used. Anisotropic permanent magnets were prepared in the same manner as in Examples 1 to 3 and Conventional Example 1, and the magnetic properties of the anisotropic permanent magnets were measured. The results are shown in Table 6.

[0050]

[Table 6]

From the results shown in Table 6, Examples 13-1
5 is superior to the anisotropic permanent magnet manufactured in Conventional Example 5 using the same raw material alloy e in the maximum energy product (BHmax). Is a rare earth -Fe-
It can be seen that a Co-B based magnet can be provided.

Examples 16 to 18 and Conventional Example 6 An alloy powder was prepared in the same manner as in Examples 4 to 6 and Conventional Example 2 except that the raw material alloy f shown in Table 1 was used. Anisotropic permanent magnets were manufactured in the same manner as in Examples 4 to 6 and Conventional Example 2, and the magnetic properties of the anisotropic permanent magnets were measured. The results are shown in Table 7.

[0053]

[Table 7]

From the results shown in Table 7, Examples 16 to 1
8 has a maximum energy product (BHmax) superior to that of the anisotropic permanent magnet manufactured in Conventional Example 6 using the same raw material alloy f. Is a rare earth -Fe-
It can be seen that a Co-B based magnet can be provided.

Examples 19 to 21 and Conventional Example 7 An alloy powder was prepared in the same manner as in Examples 7 to 9 and Conventional Example 3 except that the raw material alloy g shown in Table 1 was used. Anisotropic permanent magnets were prepared in the same manner as in Nos. 7 to 9 and Conventional Example 3, and the magnetic properties of the anisotropic permanent magnets were measured. The results are shown in Table 8.

[0056]

[Table 8]

From the results shown in Table 8, Examples 19 to 2
Since the anisotropic permanent magnet manufactured in 1 has a higher maximum energy product (BHmax) than the anisotropic permanent magnet manufactured in Conventional Example 7 using the same raw material alloy g, the production method of the present invention is Is a rare earth -Fe-
It can be seen that a Co-B based magnet can be provided.

Examples 22 to 24 and Conventional Example 8 An alloy powder was prepared in the same manner as in Examples 10 to 12 and Conventional Example 4 except that the raw material alloy h shown in Table 1 was used. Anisotropic permanent magnets were prepared in the same manner as in Examples 10 to 12 and Conventional Example 4, and the magnetic properties of the anisotropic permanent magnets were measured. The results are shown in Table 9.

[0059]

[Table 9]

From the results shown in Table 9, Examples 22 to 2
The anisotropic permanent magnet manufactured in Example 4 is superior in the maximum energy product (BHmax) to the anisotropic permanent magnet manufactured in Conventional Example 8 using the same raw material alloy h. Is a rare earth -Fe-
It can be seen that a Co-B based magnet can be provided.

[0061]

As described above, the rare earth-Fe of the present invention
According to the method for producing a -Co-B-based magnet, a rare-earth-Fe-Co-B-based magnet can be produced which is more excellent than before, and a weak coercive force hydrogen residual R-Fe having a weak coercive force.
-Co-B-based alloy powder can be sufficiently oriented in a weak magnetic field from the place where it is used, can be easily taken out of the mold without being subjected to demagnetization treatment, and the demagnetization treatment step can be omitted. Rare earth-Fe-C with excellent magnetic properties
An industrially superior effect such as production of an o-B based magnet can be achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram for explaining a method for manufacturing a rare earth-Fe—Co—B-based magnet according to the present invention.

FIG. 2 is an explanatory diagram for explaining a method for manufacturing a rare earth-Fe-Co-B-based magnet of the present invention.

FIG. 3 is an explanatory diagram for explaining a method for manufacturing a rare earth-Fe-Co-B-based magnet of the present invention.

FIG. 4 is an explanatory diagram for explaining a method for manufacturing a conventional rare earth-Fe—Co—B-based magnet.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22C 38/00 303 B22F 3/10 B 38/14 3/14 A H01F 1/053 H01F 1/04 H 1 / 08 1/08 BF term (reference) 4K018 AA11 AA27 BC02 CA04 EA01 KA45 5E040 AA04 AA19 BD01 CA01 HB03 HB06 HB07 HB11 NN01 NN12 NN17 NN18 5E062 CD04 CE04 CF05 CG02 CG03

Claims (8)

[Claims] 1. A weak coercive force hydrogen residual R having a hydrogen content of 0.01 to 0.5% by weight and a coercive force of 0.01 to 8 kOe.
-Fe-Co-B-based alloy powder (where R represents at least one rare earth element containing Y, the same applies hereinafter) while being oriented in a magnetic field to produce a green compact, and Temperature: 700 to 900 ° C., a dehydrogenation treatment until a vacuum atmosphere of 1 Torr or less is performed, and then hot pressing is performed, wherein a rare earth-Fe—Co—B-based magnet is manufactured. 2. The weak coercive hydrogen residual R-Fe-Co-B-based alloy powder having 0.01 to 0.5% by weight of hydrogen and coercive force of 0.01 to 8 kOe. -Co-
A process of storing hydrogen in the R-Fe-Co-B-based alloy ingot by raising the temperature of the B-based alloy ingot to 700 to 900 ° C in a mixed atmosphere of hydrogen or hydrogen and an inert gas (hereinafter, referred to as “below”). 2. A rare earth-Fe-Co-B magnet according to claim 1, wherein the magnet is manufactured by introducing an inert gas for a long time, cooling to room temperature, and simultaneously dehydrogenating. Manufacturing method. 3. The weak coercive hydrogen residual R-Fe-Co-B alloy powder having 0.01 to 0.5% by weight of hydrogen and coercive force of 0.01 to 8 kOe. -Co-
The B-based alloy ingot is subjected to a hydrogen absorbing treatment, and subsequently, the hydrogen-absorbed R-Fe-Co-B-based alloy powder is subjected to a temperature of 700 to 900 ° C, exceeding 1 Torr and exceeding 100 Ton.
The rare-earth element according to claim 1, wherein the rare-earth element is produced by performing incomplete dehydrogenation treatment by suction and holding until a vacuum atmosphere of rr or less is reached, and subsequently cooling the mixture to room temperature by introducing an inert gas. A method for producing a Co-B based magnet. 4. A weak coercive hydrogen-remaining R-Fe-Co-B-based alloy powder having 0.01 to 0.5% by weight of hydrogen and coercive force of 0.01 to 8 kOe. -Co-
Dehydrogenation treatment in which a B-based alloy ingot is subjected to a hydrogen storage treatment, and subsequently, the hydrogen-absorbed R-Fe-Co-B-based alloy powder is suction-held at a temperature of 700 to 900 ° C and a vacuum atmosphere of 1 Torr or less. , Followed by the introduction of an inert gas and cooling to room temperature.
The method for producing a rare-earth-Fe-Co-B-based magnet according to claim 1, wherein the magnet is produced by performing a low-temperature hydrogen absorption treatment in a hydrogen atmosphere at 00 ° C. 5. The R-Fe-Co-B-based alloy ingot is prepared in a vacuum or Ar atmosphere at a temperature of 600 to 1200.
R-Fe-Co homogenized by holding at
The method for producing a rare-earth-Fe-Co-B-based magnet according to claim 2, wherein the magnet is a -B-based alloy ingot. 6. The R—Fe—Co—B based alloy contains at least
R: 10 to 20%, Co: 0.1 to 50%, B: 3
4. The composition according to claim 1, wherein the composition contains about 20% and the balance is Fe and inevitable impurities.
The method for producing a rare earth-Fe-Co-B-based magnet according to 4 or 5. 7. The R-Fe-Co-B-based alloy contains at least
R: 10 to 20%, Co: 0.1 to 50%, B: 3
-20%, and further contains one or more of Ga, Zr, and Hf: 0.001-5.0%, with the balance having a composition consisting of Fe and unavoidable impurities. The rare earth-Fe-Co according to claim 1, 2, 3, 4 or 5.
-A method for producing a B-based magnet. 8. The R-Fe-Co-B-based alloy further comprises one or two of Al and Si in a total amount of 0.01 to 0.2.
The method for producing a rare earth-Fe-Co-B-based magnet according to claim 6 or 7, wherein the magnet has a composition containing 2.0%.