JP2000182814A - Manufacture of material alloy for nano-composite magnet and manufacture of nano-composite magnet powder and the magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture magnet powder which has satisfactory reproducibility and is suitable for effective manufacturing. SOLUTION: In a material alloy for a nano-composite magnet, general formula is represented by Fe100-x-yRxBy or Fe100-x-y-zRxByCoz, Fe100-x-y-uRxByBu or Fe100-x-y-z-uRxByCozMu, where R is a rare metal element wherein at least 90 at% of one element from among Pr and Nd or both of the elements are contained, and remainder contains greater than or equal to 0% and smaller than 10% of other lanthanum series element or at least one kind of element of Y. M is at least one kind of element selected from among a group constituted of Al, Si, Ti, V, Cr, Mn, Ni, Cu, Ca, Zr, Nb, Mo, Hf, Ta, W, Pt, Pb, Au and Ag. Composition ratios x, y, z and u satisfy 2<=x<=6, 16<=y<=20, 0.2<=z<=7 and 0.01<=u<=7. This material alloy for a nano- composite magnet is manufactured. In this case, a process, wherein molten metal of the material alloy is quenched and coagulated in a reduced pressure atmosphere by a single-roll method, is included. In this process, quenching and coagulation of the material alloy are performed in the reduced pressure atmosphere, so that quenched and coagulated alloy in a state of metal glass is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a nanocomposite magnet in which microcrystals of an Fe ₃ B compound and microcrystals of an Fe—RB compound are mixed. In particular, the present invention relates to a method for producing a raw material alloy and a powder thereof for producing a nanocomposite magnet, and a method for producing a nanocomposite magnet powder and a nanocomposite magnet. The present invention also relates to a motor and an actuator having a nanocomposite magnet and a method for producing an Fe-based quenched alloy.

[0002]

_2. Description of the Related Art In a Fe ₃ B / R ₂ Fe ₁₄ B nanocomposite magnet, Fe ₃ B microcrystals as a soft magnetic phase and R ₂ Fe ₁₄ B microcrystals as a hard magnetic phase are uniformly distributed and exchanged. They are magnets that are magnetically coupled by interaction.
These microcrystals have a size on the order of nanometers (nm) and constitute a composite structure (nanocomposite structure) of both microcrystalline phases, and are therefore called “nanocomposite magnets”.

[0003] A nanocomposite magnet can exhibit excellent magnet properties due to its magnetic coupling with a hard magnetic phase while containing a soft magnetic phase. In addition, as a result of the presence of the soft magnetic phase containing no rare earth element such as Nd, the content of the rare earth element can be kept low as a whole. This is advantageous in reducing the manufacturing cost of the magnet and stably supplying the magnet.

[0004] Such a nanocomposite magnet is manufactured using a method in which a molten raw material alloy is quenched, thereby becoming amorphous once, and then microcrystals are precipitated by heat treatment.

[0005] An alloy in an amorphous state is generally produced by a melt spinning technique such as a single roll method. In the melt spinning technique, a molten raw material alloy flows down on the outer peripheral surface of a rotating cooling roll, and the raw material alloy is rapidly cooled and solidified by bringing the molten raw material alloy into contact with the cooling roll for a short time. In this case,
The control of the cooling speed is performed by adjusting the rotation peripheral speed of the cooling roll.

The alloy that has solidified and separated from the cooling roll has a ribbon (thin strip) shape that is thin and long in the circumferential speed direction. The alloy ribbon is crushed and flaked by a breaker, and then crushed to a finer size by a crusher and powdered.

After that, heat treatment for crystallization is performed. By this heat treatment, Fe ₃ B microcrystals and R ₂ Fe
₁₄ B microcrystals are generated, and both are magnetically coupled by exchange interaction.

[0008]

What kind of metal structure is formed by heat treatment is important for improving magnet properties. However, this heat treatment had some problems in terms of controllability and reproducibility. That is, as a result of generating large heat in a short time in the crystallization reaction of the amorphous raw material alloy, there is a problem that it is difficult to control the alloy temperature by the heat treatment apparatus. In particular, when heat treatment is to be performed on a large amount of raw material alloy powder, the temperature control is likely to be impossible, so that only a small amount of raw material alloy powder can be heat treated, and the processing rate (per unit time) Powder processing amount). This has been a great obstacle to mass production of magnet powder.

Further, when producing a rapidly solidified Fe-based alloy by the same method, it is difficult to uniformly control the cooling rate during rapid solidification, so that an unnecessary structure may appear in the rapidly solidified alloy. There was a problem. This problem became remarkable especially when the roll peripheral speed was reduced and the cooling speed was reduced.

The present invention has been made in view of the above points, and a main object of the present invention is to reduce the heat of crystallization and thereby to produce a magnet powder having a fine and homogeneous metal structure with good reproducibility and efficiency. An object of the present invention is to provide a raw material alloy (powder) for a nanocomposite magnet and a method for producing the same, which are suitable for producing the same.

It is another object of the present invention to provide a method for producing a nanocomposite magnet powder having excellent magnet performance and a method for producing a nanocomposite magnet.

It is still another object of the present invention to provide a motor and an actuator having a nanocomposite magnet having such excellent characteristics.

Still another object of the present invention is to provide a method for producing a rapidly solidified Fe-based alloy in which the cooling rate can be easily controlled uniformly, and a method for producing the same.
An object of the present invention is to provide a method for producing an e-based alloy.

[0014]

Method for producing a material alloy for a nanocomposite magnet Means for Solving the Problems], the general formula _{Fe 100-xy R x B y} ,
_{Fe 100-xyz R x B y} Co z, Fe 100-xyu R x B y M u,
Or a _{Fe 100-xyzu R x B y} Co z M u material alloy for a nanocomposite magnet represented by, R represents one or both of the elements Pr and Nd containing 90 atomic% or more,
The balance is a rare earth element containing 0% or more and less than 10% of another lanthanum series element or one or more elements of Y, and M is Al, Si, Ti, V, Cr, Mn, Ni, Cu, G
a, Zr, Nb, Mo, Hf, Ta, W, Pt, Pb,
At least one element selected from the group consisting of Au and Ag, wherein the composition ratio x, y, z and u is 2 ≦ x ≦ 6,
16 ≦ y ≦ 20, 0.2 ≦ z ≦ 7, and 0.01 ≦ u
A method for producing a raw material alloy for a nanocomposite magnet satisfying ≦ 7, comprising a step of quenching and solidifying a melt of the raw material alloy by a liquid quenching method using a cooling roll, wherein the quenching of the alloy is performed in the quenching and solidifying step. Solidification is performed in a reduced pressure atmosphere, thereby producing a rapidly solidified alloy in a metallic glass state.

It is preferable that the absolute pressure of the reduced pressure atmosphere is 50 kPa or less.

The method may further include a step of producing a powder from the rapidly solidified raw material alloy.

In the rapid solidification step, the cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is reduced to 400 to 800 ° C. lower than the temperature Tm of the alloy before quenching. Preferably.

The method for producing a nanocomposite magnet powder according to the invention, general formula _{Fe 100-xy R x B y} , Fe
_{100-xyz R x B y Co} z, a _{Fe 100-xyu R x B y} M u or _{Fe 100- xyzu R x B y Co} z alloy for a nanocomposite magnet represented by M _u,, R is Pr And Nd is a rare earth element containing at least 90 at% of at least one element and Nd, and the remainder is another lanthanum series element or a rare earth element containing at least one element of Y of at least 0% and less than 10%.
i, Ti, V, Cr, Mn, Ni, Cu, Ga, Zr,
One or more elements selected from the group consisting of Nb, Mo, Hf, Ta, W, Pt, Pb, Au and Ag;
When the composition ratios x, y, z and u are 2 ≦ x ≦ 6, 16 ≦ y ≦
A step of preparing a powder of a raw alloy for a nanocomposite magnet that satisfies 20, 0.2 ≦ z ≦ 7, and 0.01 ≦ u ≦ 7; and performing a heat treatment on the powder of the raw alloy for a nanocomposite magnet. Performing a crystallization of the Fe ₃ B compound and the Fe-RB compound, thereby preparing a powder of the raw alloy for the nano composite magnet. The step is a step of rapidly solidifying the melt of the raw material alloy in a reduced pressure atmosphere by a liquid quenching method using a cooling roll to produce a rapidly solidified alloy in a metallic glass state, and producing the powder from the rapidly solidified alloy. And a step.

It is preferable that the absolute pressure of the reduced pressure atmosphere is 50 kPa or less.

In the rapid solidification step, the cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is reduced to 400 to 800 ° C. lower than the temperature Tm of the alloy before quenching. Preferably.

The method for producing a nanocomposite magnet, the general formula _{Fe 100-xy R x B y} , Fe 100-xyz R x B y Co z,
_{Fe 100-xyu R x B y} M u or _{Fe 100-xyzu} R _x B,
A _y Co _z alloy for a nanocomposite magnet represented by M _u, R is one or both of the elements Pr and Nd 9
0 at% or more, the balance being a rare earth element containing 0% or more and less than 10% of another lanthanum series element or one or more elements of Y, and M is Al, Si, Ti, V, Cr, M
n, Ni, Cu, Ga, Zr, Nb, Mo, Hf, T
a, W, Pt, Pb, Au, and Ag, which are at least one element selected from the group consisting of: 2 × x ≦ 6, 16 ≦ y ≦ 20, 0. 2 ≦ z ≦
7.0, a step of preparing a powder of the raw material alloy for a nanocomposite magnet satisfying 0.01 ≦ u ≦ 7, and subjecting the powder of the raw material alloy for a nanocomposite magnet to a heat treatment;
Thereby, the production of a nanocomposite magnet including a step of performing crystallization of the Fe ₃ B compound and the Fe—RB compound, and a step of forming a compact using the powder of the raw material alloy after the heat treatment. In the method, the step of preparing a powder of the raw material alloy for the nanocomposite magnet includes: a step of rapidly solidifying a melt of the raw material alloy in a reduced-pressure atmosphere by a liquid quenching method using a cooling roll; Producing the powder from a raw material alloy.

The absolute pressure of the reduced pressure atmosphere is 50 kPa
The following is preferred.

In the rapid solidification step, the cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is lowered to 400 to 800 ° C. lower than the temperature Tm of the alloy before quenching. Preferably.

The step of forming the compact includes a step of producing a bonded magnet using the powder of the raw material alloy after the heat treatment.

The motor of the present invention includes a nanocomposite magnet manufactured by the above-described method for manufacturing a nanocomposite magnet.

The method for producing an Fe-based rapidly solidified alloy according to the present invention is a method for producing an Fe-based rapidly solidified alloy, comprising the step of rapidly solidifying a molten Fe-based alloy by a liquid quenching method using a cooling roll, In the rapid solidification step, rapid solidification of the Fe-based alloy is performed in a reduced-pressure atmosphere, thereby forming a rapidly solidified Fe-based alloy in which a crystalline phase is 10% or less of the entirety. .

It is preferable that the absolute pressure of the reduced pressure atmosphere is 10 kPa or less.

A method for producing an Fe-based alloy is to rapidly solidify a molten Fe-based alloy in a reduced-pressure atmosphere by a liquid quenching method using a cooling roll, so that the crystalline phase is reduced to 10%.
% And a step of heating the Fe-based rapidly solidified alloy to crystallize the Fe-based rapidly solidified alloy.

Preferably, the absolute pressure of the reduced pressure atmosphere is 10 kPa or less.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the general formula is Fe
_{100-xy R x B y,} Fe 100-xyz R x B y Co z, Fe
_{100-xyu R x B y M} u or _{Fe 100-xyzu R x B y} C,
After producing a melt of o _z M alloy for a nanocomposite magnet represented by any one of _u, solidifies rapidly cooled the molten alloy.

Here, R contains 90 atomic% or more of one or both elements of Pr and Nd, and the remainder contains 0% or more and 10% or more of another lanthanum series element or one or more elements of Y.
Is a rare earth element containing less than M, M is Al, Si, T
i, V, Cr, Mn, Ni, Cu, Ga, Zr, Nb,
At least one element selected from the group consisting of Mo, Hf, Ta, W, Pt, Pb, Au and Ag. The composition ratios x, y, z and u are 2 ≦ x ≦ 6, 16 ≦ y ≦ 20,
It satisfies 0.2 ≦ z ≦ 7 and 0.01 ≦ u ≦ 7.
The reasons for limiting these compositions will be described later.

The present inventor has found that the rapid cooling and solidification of the molten alloy is preferably performed at a cooling rate of 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec. Further, it was found that the alloy solidified and cooled at such a cooling rate was in a metallic glass state as described below. That is, the Bragg scattering peak in powder X-ray diffraction contains a metastable phase Z at a position corresponding to the crystal plane spacing of 0.179 nm ± 0.005 nm, and the intensity of the Bragg reflection peak is 5% of the maximum intensity of the halo pattern. More than 200%
And the intensity of the (110) Bragg scattering peak of body-centered cubic Fe is less than 5% of the maximum intensity of the halo pattern.

Further, the inventor of the present invention quenched and solidified the above alloy in a normal pressure atmosphere using a single roll method as in the prior art.
Atmospheric gas is entrained between the molten alloy and the outer peripheral surface of the roll, and the cooling at the portion where the atmospheric gas is entrained becomes insufficient. As a result, the characteristics of the rapidly solidified alloy ribbon (alloy ribbon) partially increase. We found that it deteriorated. Less than,
This phenomenon will be described with reference to the drawings.

FIGS. 1 (a) and 1 (b) schematically show cross sections of alloy ribbons 101 and 102 obtained when the above alloy is rapidly solidified in a normal pressure atmosphere using a single roll method. Is shown. 1A shows a case where the roll peripheral speed is relatively low (roll peripheral speed: less than 10 m / sec), and FIG. 1B shows a case where the roll peripheral speed is relatively high (roll peripheral speed: 10 m / sec). Seconds or more). When the roll peripheral speed is low, the formed alloy ribbon 101 is relatively thick, and when the roll peripheral speed is high, the formed alloy ribbon 102 is relatively thin. In each case of FIGS. 1A and 1B, alloy ribbons 101 and 102 are used.
Are formed with a plurality of concave portions 105 on the lower surface of the substrate, that is, the surface that has been in contact with the cooling roll. This recess 105
This is the result of atmospheric gas being caught between the molten alloy and the outer peripheral surface of the roll. Alloy ribbons 101 and 1
In the recessed portion 02, cooling by the cooling rolls is performed only insufficiently, and the cooling rate is locally lower than in other portions. In particular, in the case of FIG. 1A, since the cooling rate is originally set to be relatively low, the cooling rate of the concave portion 105 of the alloy ribbon 101 is out of a desired range, and the α-Fe phase 106 is generated. Will be done. This α-Fe phase 106 does not disappear even after the heat treatment,
_It degrades the properties of the ₃ B / Nd ₂ Fe ₁₄ B-based nanocomposite magnet. On the other hand, in the case of FIG. 1B, the peripheral speed of the roll is high, and the alloy is rapidly cooled as a whole.
Therefore, in the concave portion 105 of the alloy ribbon 102, α
It is considered that -Fe phase is hardly generated, and instead, "metastable phase Z" described later is generated in the vicinity of the concave portion.

FIGS. 1 (c) and 1 (d) are drawings corresponding to FIGS. 1 (a) and 1 (b), respectively. The alloy ribbon 1 produced when rapid solidification is performed in a reduced pressure atmosphere is shown.
The cross sections of 03 and 104 are shown. 1C and 1D, the alloy ribbons 103 and 10
No recess is formed on the lower surface of 4, that is, the surface that has been in contact with the cooling roll. This is because the atmosphere gas was hardly entrained between the molten alloy and the outer peripheral surface of the roll, and the molten alloy was in uniform contact with the outer peripheral surface of the roll.
As a result, even when the peripheral speed of the roll is reduced and thereby the cooling rate is reduced, as shown in FIG. 1C, the surface shape of the alloy ribbon 103 does not deteriorate, and the generation of the α-Fe phase does not occur. Is suppressed. On the other hand, in the case of FIG. 1D, the alloy is uniformly cooled, but the "metastable phase Z" described later is hardly generated because the cooling rate itself is high.

As described above, in order to suppress the entrainment of the atmospheric gas between the molten alloy and the cooling roll, it is preferable to set the absolute pressure of the quenching chamber to 50 kPa or less.
It is more preferable that the pressure be kPa or less. The lower limit of the preferable range of the absolute pressure is about 1 kPa. This is because there is almost no significance in setting the pressure to a value lower than this in order to prevent entrainment of the atmospheric gas.

When the alloy or its powder rapidly solidified by the method of this embodiment is subjected to a heat treatment,
Crystallization occurs in e ₃ B crystallites and R-Fe-B-based microcrystals nanocomposite magnet structure with excellent magnetic properties is to be expressed.

The raw material alloy produced by the production method of the present invention has the above-mentioned metallic glass structure before being subjected to the heat treatment for crystallization, and does not exhibit long-range periodic order. Is confirmed from powder X-ray diffraction. According to the experiment of the present inventor, by adjusting the cooling rate of the molten alloy, a metallic glassy alloy containing the metastable phase Z can be formed, and extremely excellent magnetic properties can be exhibited by the subsequent heat treatment. Will be.

The first reason that magnets manufactured using the method of the present invention have excellent magnet properties is that the pressure between the molten metal and the cooling rolls is improved by reducing the pressure of the atmosphere gas, and the molten metal is cooled uniformly. As a result, α-
This is because a high-quality metallic glassy alloy containing almost no Fe phase can be formed.

The second reason is that, in the above alloy in the metallic glass state, fine precursors (embrios) necessary for crystal growth of Fe ₃ B or the like are dispersed at a high density. Therefore, when heat treatment is performed, crystal growth proceeds with the short-range order of many precursors present in the alloy as nuclei, and as a result, a fine and homogeneous crystal structure is formed. Further, since crystallization of Fe ₃ B proceeds by atomic diffusion in an extremely short range, there is an advantage that the crystallization can be achieved at a relatively low temperature.

The crystallization of Fe ₃ B occurs at a temperature of 560-600 ° C. With the progress of the crystallization, a rare earth element such as Nd is exuded into an amorphous region around Fe ₃ B, and the composition of the portion approaches Nd ₂ Fe ₁₄ B. As a result, N
Although d ₂ Fe ₁₄ B is a ternary compound having a complicated structure, it does not require long-range atomic diffusion,
Crystallizes. The temperature at which Nd ₂ Fe ₁₄ B crystallizes is Fe ₃
It is about 610-690 ° C., about 20-90 ° C. higher than the temperature at which crystallization of B is completed.

As described above, in the raw material alloy according to the present invention, F
Since crystallization of e ₃ B and crystallization of Nd ₂ Fe ₁₄ B can be performed separately in different temperature ranges, a large heat of reaction due to crystallization does not occur in a short time, and a fine metal structure of about 20 nm is formed. Can be generated with good reproducibility. This is important in controlling the heat treatment process for alloy crystallization. That is, if crystallization progresses at once with high reaction heat, the temperature of the alloy cannot be controlled within a predetermined range.

Although the actual structure of the metastable phase Z has not been confirmed yet, it has a sharp diffraction line peak at a specific position by X-ray diffraction, so that its existence can be quantitatively grasped. Metastable phase Z is 0.179 nm ± 0.005 nm
A sharp Bragg scattering peak is shown at a position corresponding to the crystal plane spacing of, and almost the same at positions corresponding to the crystal plane spacing of 0.417 nm ± 0.005 nm and 0.267 nm ± 0.005 nm. Shows the Bragg scattering peak of the level. Further, in addition to these, 0.134 nm ±
A Bragg peak may be shown even at 0.005 nm.

The metastable phase Z present in the alloy after rapid solidification
Is considered to be thermally decomposed by a heat treatment for magnetization to eventually produce a metastable phase Fe ₃ B. It is believed that this process proceeds at a temperature lower than the temperature at which the generation of heterogeneous nuclei of Fe ₃ B occurs most frequently, and over a relatively wide range of temperatures.

The metastable phase Z is formed near the surface of the solidified ribbon when the cooling rate during rapid solidification is relatively low, and is not generated when the cooling rate is high as in the conventional rapid solidification method. Has features. In the present invention, the cooling rate is adjusted so as to generate an appropriate amount of the metastable phase Z. That is, in the present invention, the presence of the metastable phase Z is used as an index for determining an appropriate cooling rate. Even if the composition of the alloy is changed or the cooling device is changed, if the cooling rate is set again based on the amount of metastable phase Z formed, the optimum alloy as the raw material alloy of the present invention can be easily obtained. . It is unknown whether the metastable phase Z itself plays a large role in microcrystallization. However,
It has been found that if the quenching condition is controlled so that the metastable phase Z is formed at a certain ratio, high magnetic properties can be obtained by the subsequent heat treatment.

Hereinafter, what will occur when the cooling rate is out of the predetermined range will be described.

First, the case where the cooling rate is too fast will be described.

If the cooling rate is too high, the alloy will be almost completely amorphous. In this case, since the number of sites where heterogeneous nuclei of Fe ₃ B are generated is extremely small, the crystal grains of Fe ₃ B grow large by the subsequent heat treatment. As a result, a fine crystal structure cannot be formed, the coercive force and the like decrease, and excellent magnetic properties cannot be exhibited.

When the cooling rate is too high, the formation of the metastable phase Z is suppressed. When the abundance ratio is evaluated based on the intensity of the Bragg scattering peak in X-ray diffraction, the Bragg scattering peak intensity due to the metastable phase Z is less than 5% of the maximum intensity of the halo pattern, and is at a level that is hardly observed. In this case, a large driving force is required to generate nuclei for Fe ₃ B crystallization, and the crystallization reaction temperature moves to a higher temperature side. In addition, in this case, once the crystallization reaction starts, the crystallization reaction explosively proceeds, so that a large amount of heat is generated in a short time and the temperature of the raw material alloy increases. As a result, the temperature of the raw material alloy rises to a level at which atomic diffusion occurs at a high speed, the controllability of the reaction process is lost, and only a coarse metal structure can be obtained.

When the heat treatment for crystallization is performed by using a continuous heat treatment method, it is necessary to keep the supply amount of the raw material alloy powder per unit time low so that the heat of crystallization reaction can be dissipated to the surroundings by thermal diffusion. There is. Also in the case of using a batch processing method instead of the continuous heat treatment method, it is necessary to greatly restrict the processing amount of the raw material alloy powder for the same reason.

Next, a case where the cooling rate is too slow will be described.

If the cooling rate is too slow, periodic regularities will form over a long range. In many cases, the stable phase Fe is crystallized. If the cooling rate is too slow in this way, the intensity of the Bragg reflection peak of the crystal phase is observed overlapping the halo pattern. When the (110) Bragg scattering peak, which is the strongest line of body-centered cubic Fe, is observed at a plane spacing of 0.203 nm, and its intensity is 5% or more of the maximum intensity of the halo pattern, "the cooling rate is slow. Too much ". Fe may be gamma iron in the high-temperature phase at the time of formation, but is transformed to body-centered cubic iron at room temperature.

Even if the cooling rate is set within an appropriate range for the whole alloy, as described above, if the ambient gas is caught between the alloy and the outer peripheral surface of the roll,
The cooling rate decreases locally, and a body-centered cubic Fe phase appears.

Finally, the case where the cooling rate is not slow enough to generate Fe crystal nuclei but has not reached the preferable cooling rate will be described. In this case, since the crystal nucleus embryo has already grown into a large structure, a fine crystal structure cannot be formed in a subsequent heat treatment step.
The alloy in this case contains a large amount of the metastable phase Z, and the powder X
According to the line diffraction, the intensity of the Bragg reflection peak of the metastable phase Z becomes extremely large,
Over 0%.

In the raw material alloy in which the ratio of the metastable phase Z is very large, only a coarse metal structure can be formed by the subsequent heat treatment. The reason is F
This is because the number of nucleation sites of e ₃ B is reduced and the crystal grain growth of Fe, which is an equilibrium phase, occurs preferentially. When the metal structure after the heat treatment becomes coarse, the magnetic coupling via the exchange interaction between the magnetization direction of Fe ₃ B or Fe and the magnetization direction of Nd ₂ Fe ₁₄ B becomes insufficient. As a result, it becomes impossible to express the high magnetic characteristics of the original nanocomposite magnet.

The characteristics of the raw material alloy for a nanocomposite magnet produced by the method of the present invention are summarized as follows.

1. Since the alloy is rapidly solidified in a reduced-pressure atmosphere, uniform cooling by the cooling roll is realized, and a situation in which Fe crystal nuclei are locally generated can be avoided.

2. Since crystallization of Fe ₃ B proceeds by atomic diffusion in an extremely short range, crystallization of Fe ₃ B can be performed at a relatively low temperature.

3. Since the temperature range in which the crystallization of Fe ₃ B progresses deviates from the temperature range in which the crystallization of Nd ₂ Fe ₁₄ B progresses, the respective crystallizations occur temporally separately during the heat treatment.

4. According to the above items 2 and 3, crystallization can be performed with good controllability without involving a large heat of crystallization reaction. As a result, the raw material powder throughput in the heat treatment step can be improved without deteriorating the magnet characteristics.

5. Since crystal nuclei necessary for crystallization of Fe ₃ B are present at a high density in the raw material alloy, a fine and uniform metal structure can be formed by magnetizing heat treatment. This enables the development of high magnet properties.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Production Method of Raw Material Alloy and Its Powder] In this embodiment, a raw material alloy is produced using the apparatus shown in FIGS. 2 (a) and 2 (b). In order to prevent oxidation of a raw material alloy containing a rare earth element which is easily oxidized, an alloy manufacturing process is performed in an inert gas atmosphere. It is preferable to use a rare gas such as helium or argon as the inert gas. Since nitrogen easily reacts with rare earth elements, it is not preferable to use nitrogen as an inert gas.

The apparatus shown in FIG. 2 is provided with a raw material alloy melting chamber 1 and a quenching chamber 2 capable of maintaining a vacuum or an inert gas atmosphere and adjusting the pressure.

The melting chamber 1 is a melting furnace 3 for melting a raw material 20 blended to have a desired magnet alloy composition at a high temperature.
And a hot water storage container 4 having a tapping nozzle 5 at the bottom, and a compounding material supply device 8 for supplying the compounding material into the melting furnace 3 while suppressing the entry of the atmosphere. The hot water storage container 4 has a heating device (not shown) that stores the molten metal 21 of the raw material alloy and can maintain the temperature of the molten metal at a predetermined level.

The quenching chamber 2 contains the molten metal 2 discharged from the tapping nozzle 5.
1 is provided with a rotary cooling roll 7 for rapidly cooling and solidifying 1, and a breaker 10 for crushing the rapidly solidified raw material alloy in the quenching chamber 2. According to this apparatus, melting, tapping, rapid solidification, breakage, and the like can be performed continuously and in parallel.

In this apparatus, the atmosphere and pressure in the melting chamber 1 and the quenching chamber 2 are controlled within a predetermined range. Therefore, the atmosphere gas supply ports 1b, 2b, 8b,
And 9b and gas outlets 1a, 2a, 8a and 9a
Are provided at appropriate places in the apparatus. In particular, the gas exhaust port 2a is connected to a pump in order to control the absolute pressure in the quenching chamber 2 within a range from vacuum to 50 kPa.

The melting furnace 3 can be tilted, and the molten metal 21 is appropriately poured into the hot water storage container 4 via the funnel 6. Molten 21
Is heated in the hot water storage container 4 by a heating device (not shown).

The tapping nozzle 5 of the hot water storage container 4 is disposed on the partition wall between the melting chamber 1 and the quenching chamber 2,
Flow down to the surface of the cooling roll 7 located below. The orifice diameter of the tapping nozzle 5 is, for example, 0.5 to 2.0 m.
m. When the viscosity of the molten metal 21 is large, the molten metal 21 does not easily flow in the tapping nozzle 5. However, in this embodiment, since the quenching chamber 2 is maintained at a lower pressure state than the melting chamber 1, the melting chamber 1 and the quenching chamber 2 A pressure difference is formed between the
The hot water is run smoothly.

The surface of the cooling roll 7 is covered with, for example, a chrome plating layer, and the diameter of the cooling roll 7 is, for example, 300 mm.
５００500 mm. The water cooling capacity of the water cooling device provided in the cooling roll 7 is calculated and adjusted according to the solidification latent heat and the amount of hot water per unit time.

According to the present apparatus shown in FIG.
0 kg of the raw material alloy can be rapidly solidified in 15 to 30 minutes. The alloy thus formed is an alloy ribbon (alloy ribbon) 22 having a thickness of 70 to 150 μm and a width of 1.5 to 6 mm before breaking, but the alloy having a length of about 2 to 150 mm by the breaking device 10. After being crushed into thin pieces 23, they are collected by the collection mechanism 9. In the illustrated device example, the recovery mechanism 9 is provided with the compressor 11, so that the thin section 23 can be compressed.

Next, a method for producing a raw material alloy using the apparatus shown in FIG. 2 will be described.

[0073] First, the general formula _{Fe 100-xy R x B y} , Fe
_{100-xyz R x B y Co} z, Fe 100-xyu R x B y M u, or _{Fe 100-xyzu R x B y} Co z M nanocomposite magnet alloy melt 21 represented by any one of _u It is prepared and stored in the hot water storage container 4 of the melting chamber 1. Here, the ranges of R and M and the composition ratios x, y, z and u are as described above.

Next, the melt 21 is discharged from the tapping nozzle 5 onto the water-cooled roll 7 in a reduced-pressure Ar atmosphere, rapidly cooled by contact with the water-cooled roll 7, and solidified. As the rapid solidification method, it is necessary to use a method capable of controlling the cooling rate with high precision. In the present embodiment, a single roll method, which is one of the liquid rapid cooling methods, is used.

In the present embodiment, at the time of cooling and solidifying the molten metal 21, the cooling rate is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec.
At this cooling rate, the temperature of the alloy is reduced to a temperature lower by ΔT1. Since the temperature of the molten alloy 21 before quenching is at a temperature close to the melting point Tm (for example, 1200 to 1300 ° C.), the temperature of the alloy decreases from Tm to (Tm−ΔT1) on the cooling roll 7. According to the experiment of the inventor of the present application, ΔT1 is 400 to 8 from the viewpoint of improving the final magnet properties.
It is preferably in the range of 00 ° C.

The time during which the molten alloy 21 is cooled by the cooling roll 7 corresponds to the time from the contact of the alloy with the outer peripheral surface of the rotating cooling roll 7 until the alloy is separated, and in the case of the present embodiment, 0.5. ~ 2 ms. Meanwhile, the temperature of the alloy further decreases by ΔT2 and solidifies. Thereafter, the solidified alloy leaves the cooling roll 7 and flies in an inert atmosphere. The alloy is deprived of heat by the atmospheric gas while flying in the form of a ribbon, so that its temperature becomes (Tm- △ T1- △ T).
2). ΔT2 varies depending on the size of the apparatus and the pressure of the atmosphere gas, but is about 100 ° C. or more.

In this embodiment, when the temperature of the alloy ribbon 22 reaches (Tm- △ T1- △ T2), the crushing step is immediately performed in the apparatus, and the alloy flakes 23 are produced on the spot. Therefore, (△ T1 + △ T2) is set so that (Tm- △ T1- △ T2) becomes lower than the vitrification temperature Tg of the alloy.
Is preferably adjusted. If (Tm- △
If (T1- △ T2) ≧ Tg, the alloy is in a softened state, and it is difficult to break the alloy. When the fracture / crushing step of the solidified alloy is separately performed by another device, the alloy temperature drops to about room temperature, and therefore, it is not necessary to consider the size of (ΔT1 + ΔT2).

The absolute pressure in the quenching chamber 2 is from vacuum to 5
It is preferable to set within the range of 0 kPa,
It is more preferable to set it in the range of kPa. If the molten metal 21 flows down onto the cooling roller 7 in such a decompressed atmosphere state, there is no danger that ambient gas will be spilled between the molten metal 21 and the surface of the roller 7, and the cooling rate of the molten metal 21 can be made lower than before. Even in this case, the cooling state is made uniform, and the alloy ribbon 22 excellent in surface shape and structure can be obtained.

Further, as in the present embodiment, if the crushing step of the solidified alloy by the crushing device is performed immediately after the quenching and solidifying step, the quenched alloy discharged from the cooling roll as a long alloy ribbon is relatively narrow. It can be collected compactly in space. When the quenching and solidifying device and the crushing device are configured separately, it is necessary to temporarily store the quenched alloy as a long ribbon in a bulky state.

If the alloy flakes crushed by the breaking device are further crushed by a known mechanical crushing device, an alloy powder having a size suitable for the heat treatment step and the subsequent forming step can be produced. In the present embodiment, after the alloy is roughly pulverized to about 850 μm or less with a power mill device,
Pulverize with a pin disk mill until the particle size becomes about 150 μm.

[Production Method of Nanocomposite Magnet Powder]
Hereinafter, a heat treatment method performed on the raw material alloy powder will be described with reference to FIG.

FIG. 3 shows a powder firing furnace apparatus using a hoop belt. The apparatus includes rotating rolls 24 and 25 instructed to be rotatable by a main body 28, and a hoop belt 26 driven at a predetermined speed in one direction by rotation of the rotating rolls 24 and 25.
The powder of the raw material alloy is supplied to the raw material feed position A on the hoop belt 26, and is conveyed to the left in the figure. The powder supplied on the hoop belt 26 is leveled by a sliding plate 27, whereby the height of the powder is adjusted to a certain level or less (for example, a height of 2 to 4 mm). Thereafter, the powder enters a heating zone surrounded by a metal tube, where it undergoes a heat treatment for microcrystallization. Heating zone (eg length 110
0 mm), a heater (not shown) is arranged in, for example, three zones (the length of one zone is, for example, 300 m).
m). The powder undergoes a heat treatment while moving in the heating zone. After the heating zone, for example, a length of 8
There is a cooling zone C of 00 mm and the powder is cooled by passing through a water-cooled metal cylinder. The cooled powder is collected by a collecting device (not shown) at the lower left of the rotating roller 25.

According to this heat treatment apparatus, the heat treatment step can be controlled by adjusting the moving speed of the hoop belt 26 for a given length of the heating zone.

As the heat treatment step, for example, a heat treatment temperature of 590 to 700 ° C. at a rate of 100 to 150 ° C./min.
, And hold that state for about 5 to 15 minutes. After that, the alloy temperature is lowered to a rate of 100-
Reduce to room temperature level at 150 ° C./min.

In order to increase the amount of powder to be treated in the heat treatment, the width of the hoop belt 26 should be increased,
It is sufficient to increase the length of the heating zone and increase the peripheral speed of rotation of the rotating rollers 24 and 25 while increasing the amount of powder supplied per unit length. According to the alloy powder according to the present invention, since a large heat of crystallization reaction is not generated suddenly during the heat treatment, it is easy to control the temperature of the alloy powder in the heat treatment step. As a result, a magnet powder having stable magnetic properties can be produced even if the amount of supplied powder is increased.

[0086] The raw material powder that has been heat-treated by the heat treatment apparatus is microcrystallized as described above, and can exhibit properties as a nanocomposite magnet. Thus,
Before the heat treatment, the raw material alloy powder, which is in a metallic glass state and does not show the properties as a hard magnetic material, changes to a nanocomposite magnet alloy powder having excellent magnetic properties by the heat treatment.

[Method of Manufacturing Magnet] A method of manufacturing a magnet from the above nanocomposite magnet alloy powder will be described below.

First, a compound made by adding a binder made of an epoxy resin and an additive to the nanocomposite magnet alloy powder obtained as described above and kneading it is prepared. Next, after the compound is press-molded by a molding apparatus having a molding space of a desired shape, a final bonded magnet can be obtained through a heat curing step, a washing step, a coating step, an inspection step, and a magnetization step.

The molding process is not limited to the above-mentioned compression molding, but may be a known extrusion molding, injection molding or rolling molding. The magnet powder is kneaded with a plastic resin or rubber depending on the type of molding method to be employed.

In the case of injection molding, a resin having a high softening point such as PPS can be used in addition to polyimide and nylon widely used as resins. this is,
This is because the magnet powder of the present invention is formed from a low-rare-earth alloy, so that it is not easily oxidized, and magnet characteristics do not deteriorate even when injection molding is performed at a relatively high temperature.

Since the magnet of the present invention is hardly oxidized, it is not necessary to coat the final magnet surface with a resin film. Therefore, for example, it is also possible to press-fit the magnet powder and the molten resin of the present invention into a slot of a component having a slot having a complicated shape by injection molding, thereby manufacturing a component integrally provided with a magnet having a complicated shape. It is possible.

[Motor] Next, an embodiment of a motor provided with the magnet thus manufactured will be described.

The motor of the present embodiment has a PM (Permanent
Magnet) type motor, in which the bond magnet produced by the above-described manufacturing method is used as a spring magnet of the integrated rotor.

It goes without saying that the magnet of the present invention can be suitably used for other types of motors and actuators besides this type of motor.

Hereinafter, examples of the present invention and comparative examples will be described.

[Examples and Comparative Examples] In this example, the above-mentioned rapid solidification step was performed in an argon atmosphere having an absolute pressure of 50 kPa or less. As cooling roll, thickness 5-15μ
Roll made of copper alloy (diameter:
350 mm). 10m /
While rotating at a peripheral speed of seconds, the molten metal of the raw material alloy was allowed to flow down on the outer peripheral surface thereof, and was rapidly solidified. The temperature of the molten metal was 1300 ° C. as measured with a radiation thermometer. The molten metal
1.3 diameter from the orifice at a rate of 10-20 g / s
に し て 1.5 mm and dropped.

FIG. 4 is a graph showing how the coercive force and the residual magnetic flux density depend on the temperature of the crystallization heat treatment. In this graph, the black circles indicate that the solidification was rapid-solidified at a roll peripheral speed of 9 m / sec in an Ar atmosphere of 1.3 kPa (Example 1), and the x symbols indicate that the roll peripheral speed was 9 m / sec in an Ar atmosphere of 50 kPa. In the case of rapid solidification (Example 2), white circles indicate data in the case of rapid solidification at a roll peripheral speed of 20 m / sec in a normal pressure Ar atmosphere (Comparative Example).

As can be seen from FIG. 4, in Examples 1 and 2, superior magnetic properties were obtained over the comparative example over a wide temperature range.

FIG. 5 is a graph showing how the coercive force and the residual magnetic flux density depend on the throughput per unit time. In this graph, black circles indicate A of 1.3 kPa.
In the case of rapid solidification at a roll peripheral speed of 9 m / sec in an r atmosphere (Example 1), a black square indicates the case of rapid solidification at a roll peripheral speed of 20 m / sec in a normal pressure Ar atmosphere (comparative example). Shows the data.

As can be seen from FIG. 5, in Example 1, excellent magnetic characteristics were obtained with a larger throughput than in the comparative example.

[Reason for Limiting Composition] Finally, Fe ₃ B / Nd ₂
The reasons for limiting the raw material alloy composition for the Fe ₁₄ B-based nanocomposite magnet will be described.

The rare earth element R is composed of the hard magnetic phase R ₂
It is an essential element for Fe ₁₄ B. R in the present invention contains one or both elements of Pr and Nd in an amount of 90 atomic% or more, and the balance contains other lanthanum series elements or one or more elements of Y in an amount of 0% or more and less than 10%. One of the elements Pr and Nd is R ₂ F having uniaxial crystal magnetic anisotropy.
essential to produce e ₁₄ B. Pr and Nd
The rare earth elements other than are appropriately selected arbitrarily. If the composition ratio of R is less than 2 atomic%, the effect of generating a coercive force is too small, which is not preferable. On the other hand, if the composition ratio of R exceeds 6 atomic%, the Fe ₃ B phase and the Nd ₂ Fe ₁₄ B phase are not generated, and the α-Fe phase becomes the main phase. Will be lost. From the above, it is preferable that the composition ratio x of R satisfy 2 ≦ x ≦ 6.

B is an essential element for both the soft magnetic phase Fe ₃ B and the hard magnetic phase R ₂ Fe ₁₄ B. If the composition ratio y of B is out of the range of 16 to 20 at%, the required coercive force is not exerted. Therefore, the composition ratio y of B is preferably 16 ≦ y ≦ 20.
Further, when B is out of this composition range, the melting point rises, and it becomes necessary to increase the melting temperature and the heat retaining temperature of the hot water storage container,
In addition, since the ability to form an amorphous phase is also reduced, it is difficult to obtain a desired rapidly cooled alloy structure.

Co has the function of reducing the temperature change dependence of the magnetic characteristics by improving the Curie temperature, thereby stabilizing the magnetic characteristics. Also,
It also has the function of improving the viscosity of the molten alloy and contributes to the stabilization of the flow rate of the molten metal. Co addition ratio is 0.0
If the amount is less than 2 atomic%, the above function is not sufficiently exhibited, and if it exceeds 7 atomic%, the magnetization characteristics start to deteriorate. The addition of Co may be performed when it is desired to exhibit these functions, and the addition of Co is not indispensable for obtaining the effects of the present invention. When Co is added, it is preferable that 0.2 ≦ z ≦ 7 is satisfied for the composition ratio z for the above-described reason.

M is added when it is desired to increase the coercive force as much as possible. When the addition ratio of M is less than 0.01 at%, the increase in coercive force is not sufficiently observed, and when the addition ratio of M exceeds 7 at%, the magnetization decreases. Therefore, when M is added, for the composition ratio u, 0.1 ≦ z ≦
7 is preferably satisfied. Among M, Cr exerts an effect of improving corrosion resistance in addition to an increase in coercive force. Also, Cu,
Au and Ag have the effect of expanding the appropriate temperature range in the crystallization heat treatment step.

[Manufacturing method of Fe-based rapidly solidified alloy] Even when an Fe-based rapidly solidified alloy is manufactured under normal pressure by the one-roll method, the adhesion between the cooling roll and the alloy is reduced due to the entrainment of the atmosphere gas. As a result, there arises a problem that the cooling rate becomes non-uniform depending on the portion of the alloy ribbon. Produces a rapidly solidified Fe-based alloy that partially contains a crystalline phase, compared to the case of producing an alloy-based ribbon that is entirely crystalline or an Fe-based rapidly solidified alloy that is substantially all amorphous. In this case, it is necessary to control a relatively slow cooling rate within a predetermined range with high accuracy. In such a case, a problem as shown in FIG. 1A may occur under normal pressure.

Therefore, according to the present invention, the general formula is Fe _{100-xy
R x B y, Fe 100-} xyz R x B y Co z, Fe 100-xyu R x
There is intended to exert a remarkable effect when applied to B _y M _u or _{Fe 100-xyzu R x B y} Co z M u in the material alloy for a nanocomposite magnet represented, but, the crystalline phase the whole This is also effective when producing an Fe-based rapidly solidified alloy in a state of 10% or less. Such an Fe-based rapidly solidified alloy is crystallized by a subsequent heat treatment, so that a uniform metal structure can be expressed with good reproducibility. In addition, the influence of entanglement tends to be significant when the peripheral speed of the cooling roll is reduced, so that it is difficult to reduce the peripheral speed of the roll in a normal pressure atmosphere. Generally, the lower the roll peripheral speed, the slower the deterioration of the cooling roll. Therefore, according to the present invention, there is also an advantage that the cooling roll can be used for a long time with high reliability.

The Fe-based rapidly solidified alloy is, for example, Nd ₁₃ Fe ₈₂ B ₅ , Fe ₇₄ Cu ₁ Nb ₃ Si
₁₆ B ₆ , Fe ₉₁ Zr ₇ B ₂ , Fe ₉₁ Hf ₇ B _{2 and the} like are included.

[0109]

According to the present invention, uniform cooling is realized because the adhesion between the cooling roll and the molten metal is improved by the reduced pressure atmosphere. Therefore, a desired metallic glass-like alloy is obtained, and the magnetic properties after the heat treatment are improved. In addition, Fe ₃
The heat of crystallization for forming the B / Nd ₂ Fe ₁₄ B-based nanocomposite magnet is dispersed in a wide temperature range, and the microcrystallization is performed with good controllability without releasing a large heat of crystallization at once. As a result, the throughput of the raw material powder in the heat treatment step can be improved without deteriorating the magnet characteristics.

Since the crystal nuclei necessary for crystallization of Fe ₃ B are present in the raw material alloy at high density and the Fe phase is small, a fine and uniform metal structure can be formed by the heat treatment with magnetization. Enables the development of magnet properties.

[Brief description of the drawings]

1 (a) and 1 (b) are schematic cross-sectional views of an alloy ribbon obtained when the above alloy is rapidly solidified in a normal pressure atmosphere using a single roll method as in the past, and FIG. 1 (c). And (d) are drawings corresponding to (a) and (b), respectively, and are schematic cross-sectional views of an alloy ribbon produced when rapid solidification is performed in a reduced-pressure atmosphere.

FIG. 2A is a cross-sectional view showing an example of an entire configuration of an apparatus used for a method for producing a raw material alloy for a nanocomposite magnet according to the present invention, and FIG. 2B is an enlarged view of a portion where rapid solidification is performed. is there.

FIG. 3 is a cross-sectional view illustrating an example of a heat treatment apparatus used for a method of manufacturing a nanocomposite magnet according to the present invention.

FIG. 4 is a graph showing how the coercive force and the residual magnetic flux density depend on the temperature of the crystallization heat treatment.

FIG. 5 is a graph showing how the coercive force and the residual magnetic flux density depend on the throughput per unit time.

[Explanation of symbols]

 1b, 2b, 8b, and 9b Atmosphere gas supply ports 1a, 2a, 8a, and 9a Gas exhaust ports 1 Melting chamber 2 Quenching chamber 3 Melting furnace 4 Hot water storage tank 5 Hot water nozzle 6 Roth 7 Rotary cooling roll 10 Breaker 10 11 Compression Machine 21 Molten metal 22 Alloy thin strip 23 Alloy thin piece 28 Main body 24 Rotating roll 25 Rotating roll 26 Hoop belt 27 Sliding plate

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01F 41/02 H01F 1/06 A F term (Reference) 4K018 AA27 CA50 KA45 5E040 AA04 AA19 BB04 BB05 BD00 CA01 HB07 HB11 HB15 HB17 HB19 NN01 NN17 NN18 5E062 CC05 CD04 CD05 CE01 CE04 CG02

Claims (16)

[Claims] 1. A general formula _{Fe 100-xy R x B y} , Fe
_{100-xyz R x B y Co} z, a _{Fe 100-xyu R x B y} M u or _{Fe 100-xyzu R x B y} Co z M raw material alloy for a nanocomposite magnet represented by _u,, R is Pr and Nd
90% by atom or more, and the balance is 0% or more with other lanthanum series elements or one or more elements of Y.
% To less than 10%, and M is A
1, Si, Ti, V, Cr, Mn, Ni, Cu, Ga,
Zr, Nb, Mo, Hf, Ta, W, Pt, Pb, Au
And at least one element selected from the group consisting of Ag and Ag, wherein the composition ratio x, y, z and u is 2 ≦ x ≦ 6, 16
≦ y ≦ 20, 0.2 ≦ z ≦ 7, and 0.01 ≦ u ≦ 7
In the method for producing a raw material alloy for a nanocomposite magnet that satisfies the following, the method includes a step of rapidly solidifying a molten metal of the raw material alloy by a liquid quenching method using a cooling roll. A method for producing a raw alloy for a nanocomposite magnet, which is performed in a reduced-pressure atmosphere, thereby producing a rapidly solidified alloy in a metallic glass state. 2. An absolute pressure of the reduced pressure atmosphere is 50 kPa.
The method for producing a raw material alloy for a nanocomposite magnet according to claim 1, wherein: 3. The method for producing a raw material alloy for a nanocomposite magnet according to claim 1, further comprising a step of producing a powder from the rapidly solidified raw material alloy. 4. In the rapid solidification step, a cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is lowered by 400 to 800 ° C. from the temperature Tm of the alloy before quenching. The method for producing a raw material alloy for a nanocomposite magnet according to any one of claims 1 to 3, wherein the raw material alloy is reduced. Wherein general formula _{Fe 100-xy R x B y} , Fe
_{100-xyz R x B y Co} z, a _{Fe 100-xyu R x B y} M u or _{Fe 100-xyzu R x B y} Co z M u alloying nanocomposite magnet represented by,, R is Pr And Nd is a rare earth element containing at least 90 at% of at least one element and Nd, and the remainder is another lanthanum series element or a rare earth element containing at least one element of Y of at least 0% and less than 10%.
i, Ti, V, Cr, Mn, Ni, Cu, Ga, Zr,
One or more elements selected from the group consisting of Nb, Mo, Hf, Ta, W, Pt, Pb, Au and Ag;
When the composition ratios x, y, z and u are 2 ≦ x ≦ 6, 16 ≦ y ≦
A step of preparing a powder of a raw alloy for a nanocomposite magnet satisfying 20, 0.2 ≦ z ≦ 7, and 0.01 ≦ u ≦ 7; and performing a heat treatment on the powder of the raw alloy for a nanocomposite magnet. And thereby the Fe ₃ B compound and Fe
Performing a crystallization of the RB-based compound, wherein the step of preparing a powder of the raw material alloy for the nanocomposite magnet comprises cooling the molten metal of the raw material alloy. A step of rapidly solidifying in a reduced pressure atmosphere by a liquid quenching method using a roll to produce a rapidly solidified alloy in a metallic glass state, and a step of producing the powder from the rapidly solidified alloy, Of producing nanocomposite magnet powder. 6. An absolute pressure of the reduced pressure atmosphere is 50 kPa.
The method for producing a nanocomposite magnet powder according to claim 5, wherein: 7. In the rapid solidification step, the cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is lowered by 400 to 800 ° C. from the temperature Tm of the alloy before quenching. 7. The method for producing a nanocomposite magnet powder according to claim 5, wherein 8. A general formula _{Fe 100-xy R x B y} , Fe
_{100-xyz R x B y Co} z, a _{Fe 100-xyu R x B y} M u or _{Fe 100-xyzu R x B y} Co z M u alloying nanocomposite magnet represented by,, R is Pr And Nd is a rare earth element containing at least 90 at% of one or both elements, and the balance is another lanthanum series element or a rare earth element containing one or more elements of Y at 0% or more and less than 10%.
i, Ti, V, Cr, Mn, Ni, Cu, Ga, Zr,
One or more elements selected from the group consisting of Nb, Mo, Hf, Ta, W, Pt, Pb, Au and Ag;
When the composition ratios x, y, z, and u are 2 ≦ x ≦ 6, 16 ≦ y ≦
20, a step of preparing a powder of a raw material alloy for a nanocomposite magnet satisfying 0.2, z ≦ 7.0, and 0.01 ≦ u ≦ 7; and a heat treatment for the powder of the raw material alloy for a nanocomposite magnet. And thereby the Fe ₃ B compound and Fe
A method for producing a nanocomposite magnet, comprising: a step of performing crystallization of an RB-based compound; and a step of forming a molded body using the raw material alloy powder after the heat treatment, wherein the nanocomposite magnet is provided. A step of preparing a powder of the raw material alloy for use; a step of rapidly solidifying a melt of the raw material alloy in a reduced-pressure atmosphere by a liquid quenching method using a cooling roll; and a step of producing the powder from the rapidly solidified raw alloy. A method for producing a nanocomposite magnet comprising: 9. An absolute pressure of the reduced pressure atmosphere is 50 kP.
The method for producing a nanocomposite magnet according to claim 8, wherein a is equal to or less than a. 10. In the rapid solidification step, the cooling rate of the alloy is set to 5 × 10 ^{4 to} 5 × 10 ⁶ K / sec, and the temperature of the alloy is reduced by 400 to 800 ° C. from the temperature Tm of the alloy before quenching. The method for producing a nanocomposite magnet according to claim 8, wherein the magnetic field is reduced. 11. The production of the nanocomposite magnet according to claim 8, wherein the step of forming the molded body includes a step of producing a bond magnet using the powder of the raw material alloy after the heat treatment. Method. 12. A motor comprising a nanocomposite magnet manufactured by the method for manufacturing a nanocomposite magnet according to claim 8. 13. A method comprising the step of rapidly solidifying a molten Fe-based alloy by a liquid quenching method using a cooling roll.
A method for producing an e-based rapidly solidified alloy, wherein in the rapid solidification step, rapid solidification of the Fe-based alloy is performed in a reduced-pressure atmosphere, whereby the crystalline phase is less than 10% of the total. A method for producing a rapidly solidified Fe-based alloy, the method comprising forming a rapidly solidified alloy. 14. An absolute pressure of the reduced pressure atmosphere is 10 kP.
a or less than a.
Production method of rapidly solidified alloys. 15. A liquid quenching method using a chill roll to rapidly solidify a molten Fe-based alloy in a reduced-pressure atmosphere, whereby the crystalline phase is less than 10% of the total.
A method for producing an Fe-based alloy, comprising: a step of forming an e-based rapidly solidified alloy; and a step of heating the Fe-based rapidly solidified alloy to crystallize the Fe-based rapidly solidified alloy. 16. An absolute pressure of the reduced pressure atmosphere is set to 10 kP.
a or less than a.
Production method of base alloy.