JPH11309549A - Manufacture of magnet material, magnet material and bond magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of magnet material having high magnetic characteristic, a magnet material, and a bond magnet. SOLUTION: A quenched strip manufacturing device 1 is provided with a cylindrical body 2, a heating coil 4, and a cooling roll 5 to be rotated relative to the cylindrical body 2. A nozzle 3 to eject molten metal 6 of a magnet material is formed on a lower end of the cylindrical body 2. In an atmospheric gas, the molten metal 6 is ejected from the nozzle 3, and collided with a circumferential surface 53 of the rotating cooling roll 5, and cooled and solidified to a quenched strip 8. A metallic material to constitute the circumferential surface 53 of the cooling roll 5 has wettability so that the contact angle formed on the horizontal surface of a solidified metal is 70-170 deg. when a droplet of the molten metal 6 is placed and solidified on the horizontal surface of the metallic material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a magnet material, a magnet material, and a bonded magnet.

[0002]

2. Description of the Related Art As a magnet material, a rare earth magnet material composed of an alloy containing a rare earth element has high magnetic properties, and therefore exhibits high performance when used in a motor or the like.

[0003] Such a magnet material is produced, for example, by a quenching method using a quenching ribbon manufacturing apparatus. This manufacturing method is as follows.

A magnet material having a predetermined alloy composition (hereinafter referred to as “alloy”)
Is melted, and the molten metal is injected from the nozzle and collides with the peripheral surface of the cooling roll rotating with respect to the nozzle,
The alloy is quenched and solidified by being brought into contact with the peripheral surface to continuously form a ribbon-shaped (ribbon-shaped) alloy. This ribbon-shaped alloy is called a quenched ribbon.

By the way, the molten metal injected from the nozzle is
When it collides with the peripheral surface of the cooling roll, a paddle (pool) is formed first, and then cooled and solidified. However, when the cooling speed is slow, crystal grains are coarsened and magnetic properties are deteriorated.

For this reason, a material having excellent heat conductivity has been selected as a metal material constituting the peripheral surface of the cooling roll.

[0007]

However, in recent years,
Even when a metal material having excellent thermal conductivity is used for the peripheral surface of the cooling roll, there is a problem that the magnetic properties may be low in some cases.

[0008] An object of the present invention is to provide a method of manufacturing a magnet material capable of obtaining high magnetic properties, a magnet material, and a bonded magnet.

[0009]

[MEANS FOR SOLVING THE PROBLEMS] The volume flow Q of the quenched ribbon
(Volume of quenched ribbon produced per unit time = volume of molten metal injected per unit time) is given by the following formula, when the width w of the quenched ribbon, the thickness t, and the peripheral speed V of the cooling roll are given by It is represented by (I).

Q = w × t × V (I) On the other hand, if the wettability of the peripheral surface of the cooling roll with the molten metal (hereinafter simply referred to as “roll peripheral surface wettability”) is good, the paddle becomes The width w of the quenched ribbon becomes large because it tends to spread over a larger area on the peripheral surface of the cooling roll, and conversely, if the wettability of the roll peripheral surface is poor, the width w of the quenched ribbon becomes small.

Therefore, when a quenched ribbon is manufactured with the cooling roll peripheral speed V and the quenched ribbon volume constant, the following formula (I) indicates that the roll peripheral surface has good wettability.
A rapidly quenched ribbon having a large width w and a small thickness t can be obtained. Conversely, if the roll has poor wettability, a rapidly quenched ribbon having a small width w and a large thickness t can be obtained.

When the thickness t of the quenched ribbon is small, heat transfer in the thickness direction is performed in a short time, which is advantageous for refining crystal grains. However, when the thickness t of the quenched ribbon is large, Poor heat transfer in the thickness direction, especially the cooling speed between the roll surface of the quenched ribbon (the surface that contacts the peripheral surface of the cooling roll) and the free surface (the surface that does not contact the peripheral surface of the cooling roll) And the crystal grains tend to become coarse on the free surface side.

In view of the above, the present inventor paid attention to the wettability of the roll peripheral surface and conducted intensive research. As a result, by using a cooling roll with the wettability of the roll peripheral surface within a predetermined range, The present inventors have found that crystal grains can be refined and excellent magnetic properties can be obtained, and the present invention has been accomplished.

That is, the present invention provides the following (1) to (13)
As shown in FIG.

(1) Production of magnet material for injecting molten material of magnet material from a nozzle, impinging on the peripheral surface of a cooling roll rotating with respect to the nozzle, cooling and solidifying to produce a ribbon-shaped magnet material The method according to claim 1, wherein the metal material forming the peripheral surface of the cooling roll is placed on a horizontal surface of the metal material, and when the molten metal droplet is placed and solidified, a contact between the solidified material and the horizontal surface is formed. A method for producing a magnet material, wherein the angle is 70 to 170 °.

(2) A melt of magnet material is injected from a nozzle in an atmosphere gas, and collides with a peripheral surface of a cooling roll rotating with respect to the nozzle, and is cooled and solidified to produce a ribbon-shaped magnet material. A method of manufacturing a magnet material, wherein the metal material forming the peripheral surface of the cooling roll places droplets of the molten metal on a horizontal surface of the metal material in a gas of the same type and the same pressure as the atmospheric gas, A method for producing a magnet material, wherein when solidified, a contact angle between the solidified matter and the horizontal surface is 70 to 170 °.

(3) The peripheral speed of the cooling roll is 1 to
The method for producing a magnetic material according to the above (1) or (2), wherein the magnetic material is 60 m / sec.

(4) Any of the above (1) to (3), wherein the maximum eccentricity of the peripheral surface of the cooling roll due to the rotation of the cooling roll is not more than twice the average thickness of the obtained ribbon-shaped magnet material. The method for producing a magnetic material according to any one of the above.

(5) The method according to any one of (1) to (4), wherein the atmosphere gas is an inert gas.

(6) The magnet material is R (where R
Is a alloy containing at least one of the rare earth elements containing Y). The method for producing a magnetic material according to any one of the above (1) to (5), wherein

(7) The magnet material is R (where R
Is at least one of the rare earth elements containing Y) and T
M (where TM is at least one of the transition metals
The method for producing a magnetic material according to any one of the above (1) to (5), which is an alloy containing a seed) and B.

(8) A ribbon-shaped magnet material produced by the method for producing a magnet material according to any one of the above (1) to (7).

(9) A powdered magnet material obtained by pulverizing the magnet material described in (8) to form a powder.

(10) A bonded magnet, wherein the powdered magnetic material according to (9) is bonded with a bonding resin.

(11) The bonded magnet according to the above (10), wherein the content of the powdery magnet material is 82 to 99.5 wt%.

(12) The bonded magnet according to the above (10) or (11), wherein the coercive force iHc is 0.35 MA / m or more.

(13) The magnetic energy product (BH) max is 50
The bonded magnet according to any one of the above (10) to (12), which has a kJ / m of ³ or more.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for manufacturing a magnet material, a magnet material and a bonded magnet according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a perspective view showing an example of the structure of a device for manufacturing the magnet material of the present invention by a single-roll method (a quenched ribbon manufacturing device), and FIG. 2 is a view showing the structure of the apparatus shown in FIG. FIG. 4 is a cross-sectional side view showing a state near a collision site of FIG.

As shown in FIG. 1, a quenched ribbon manufacturing apparatus 1
Has a cylindrical body 2 capable of storing a magnet material, and a cooling roll 5 that rotates in the direction of arrow A in FIG.
A nozzle (orifice) 3 for injecting the molten metal of the magnet material is formed at the lower end of the cylinder 2.

On the outer periphery of the cylinder 2 near the nozzle 3,
A heating coil 4 is arranged, and the inside of the cylinder 2 is heated (induction heating) by applying, for example, a high frequency to the coil 4 to bring the magnet material in the cylinder 2 into a molten state.

The cooling roll 5 comprises a base 51 and a surface layer 52 forming a peripheral surface 53 of the cooling roll 5.

The constituent material of the base portion 51 may be integrally formed of the same material as the surface layer 52, or may be formed of a material different from that of the surface layer 52.

The constituent material of the base portion 51 is not particularly limited, but is made of a metal material having a high thermal conductivity such as copper or a copper-based alloy so that the heat of the surface layer 52 can be dissipated more quickly. Is preferred.

The surface layer 52 is preferably made of a metal material as described below.

The quenched ribbon manufacturing apparatus 1 is installed in a chamber (not shown), and operates in a state where the chamber is preferably filled with an inert gas or other atmospheric gas. In particular, in order to prevent the quenched ribbon 8 from being oxidized, the atmosphere gas is preferably an inert gas.

Examples of the inert gas include, for example, argon gas, helium gas, nitrogen gas and the like, and helium gas is particularly preferable. The reason is that when helium gas is used as the atmosphere gas, dimples due to entrainment of the gas flow on the roll surface 81 of the quenched ribbon 8, particularly, the area of 200
Giant dimples 13 of 0 μm ² or more (indicated by phantom lines in FIG. 2) are less likely to occur, heat transfer is improved, and higher magnetic properties are obtained.

In the quenched ribbon manufacturing apparatus 1, a magnet material is put into a cylindrical body 2, heated and melted by a coil 4, and the molten metal 6 is injected from a nozzle 3. As shown in FIG. After colliding with the peripheral surface 53 of the cooling roll 5 to form a paddle (pool) 7, the peripheral surface 53 of the rotating cooling roll 5 is rotated.
Rapidly cooled and solidified while being dragged by
Are formed continuously or intermittently. The roll surface 81 of the quenched ribbon 8 formed in this way eventually separates from the peripheral surface 53 and advances in the direction of arrow B in FIG. In FIG. 2, the solidification interface 71 of the molten metal is indicated by a dotted line.

The peripheral speed V of the cooling roll 5 varies in a suitable range depending on the composition of the molten alloy, the wettability of the peripheral surface 53 to the molten metal 6, and the like, but is generally preferably 1 to 60 m / sec. More preferably, it is 40 m / sec. If the peripheral speed of the cooling roll 5 is too slow, the thickness t of the quenched ribbon 8 becomes thicker depending on the volume flow rate Q of the quenched ribbon 8 (see the above formula (I)), the crystal grain size increases, and conversely. If the peripheral speed V of the cooling roll 5 is too high, the cooling roll 5 becomes amorphous, and in any case, the magnetic characteristics deteriorate.

The metal material forming the peripheral surface 53 of the cooling roll 5, that is, the metal material forming the surface layer 52 (hereinafter referred to as “roll peripheral surface material”) has wettability to the molten metal 6 (hereinafter simply referred to as “roll peripheral material”). "Wetability"). That is, as shown in FIG. 3, a horizontal surface 10 is formed by the roll peripheral surface material 9, and a droplet of the molten metal 6 is placed on the horizontal surface 10 and solidified.
Has a contact angle θ of 70 to 170 ° with the horizontal surface 10. In this case, the contact angle θ is 80 to 165 °
Is preferably 90 to 160 °, more preferably 95 to 150 °.

Here, instead of directly measuring the wettability of the peripheral surface 53 of the cooling roll 5, the horizontal surface 10 is formed of the same material (roll peripheral surface material) and the wettability of the horizontal surface 10 is measured. This is because since the peripheral surface 53 is a curved convex surface, the droplet of the molten metal 6 cannot be stopped at a certain position and cannot be measured, and the measurement of the contact angle is impossible or difficult.

When measuring the contact angle θ, in order to more accurately obtain the correspondence with the wettability of the peripheral surface 53 of the cooling roll 5 used in the actual production of the quenched ribbon, the liquid of the molten metal 6 is used. The solidification of the droplets is preferably performed in a gas of the same kind and pressure as the atmospheric gas. The volume of the coagulated material 11 is
It is preferable to measure in the range of 0.005 to 0.1 cm ³ .

When the contact angle θ exceeds the upper limit of the above range,
The wettability of the peripheral surface 53 is poor, and the thickness t of the quenched ribbon 8 tends to increase depending on the volume flow rate Q of the quenched ribbon 8, and particularly the crystal grains on the free surface 82 side of the quenched ribbon 8 become coarse. As a result, the magnetic characteristics deteriorate. Even in this case, if the volume flow rate Q is reduced, the thickness t is also reduced (the above-described equation (I)).
), But such disadvantages are eliminated or alleviated, but this is not preferable because it causes a decrease in productivity.

If the contact angle θ is less than the lower limit of the above range, the wettability of the peripheral surface 53 is too good, so that the paddle 7 is too wide, so that the shape and dimensions (width w, width w, Thickness t) becomes unstable, uniform and homogeneous quenched ribbon 8
Cannot be obtained (variation occurs in the state of crystal grains, magnetic characteristics, etc.).

In the measurement of the contact angle θ, separation (floating) 12 as shown in FIG. 4 may occur due to solidification shrinkage near the solidification interface where the droplet of the molten metal 6 contacts the horizontal surface 10. . In this case, the contact angle θ is measured excluding the portion where the separation 12 has occurred. That is, the contact angle θ is measured using a plane 10 ′ parallel to the horizontal surface 10 passing through the upper end (apex) of the peeling 12 as a reference plane.

By the way, in the quenching ribbon manufacturing apparatus 1, when the cooling roll 5 rotates, as shown in FIG. 5, due to the dimensional accuracy (roundness) of the cooling roll 5 itself and the mounting accuracy of the cooling roll 5 to the bearing. As shown, slight eccentricity (axial runout) occurs.

If the eccentricity is large, the surface of the molten alloy and the solidification interface 71 in the paddle 7 vibrate, and the dimensions (width w, thickness t) of the obtained quenched ribbon 8 fluctuate, or the quenched ribbon 8 changes. The time during which the roll surface 81 of 8 is in contact with the peripheral surface 53 of the cooling roll 5 may fluctuate. Further, the occurrence rate of the huge dimple 13 also increases. As a result, quenched ribbon 8
The cooling speed and the like of the magnetic field fluctuate, and the magnetic characteristics vary.
The magnetic properties of the magnet powder obtained from such a quenched ribbon 8 and the bonded magnet using the same also deteriorate.

In order to prevent such a situation, according to the present invention, the peripheral surface 5 of the cooling roll 5 is rotated by the rotation of the cooling roll 5.
3, the maximum eccentricity ΔR (see FIG. 5) is preferably not more than twice the thickness (average value) t of the quenched ribbon 8 obtained.
It is more preferably 1.5 times or less, further preferably 1 time or less. Thereby, the quenched ribbon 8 obtained is obtained.
Can have more uniform magnetic properties. And the magnetic property of the bonded magnet manufactured from this can be improved. In particular, in the present invention, such a maximum eccentric amount ΔR
And the synergistic effect of defining the wettability of the peripheral surface 53 described above can exhibit more excellent magnetic properties.

Here, the lower limit value of the maximum eccentric amount ΔR is not particularly limited, but is 0.1 μm from the limit of the processing accuracy of the peripheral surface 53 of the cooling roll 5 and the limit of the accuracy of the bearing supporting the cooling roll 5. Degree.

The maximum amount of eccentricity ΔR can be measured by a precision dimension measuring device such as a laser displacement meter, an electrostatic displacement meter, and a precision gauge.

As the magnet material in the present invention, R (where R is at least one of rare earth elements including Y)
Species), particularly R (where R is at least one of the rare earth elements including Y) and TM (where TM
Are rare earth magnet materials such as alloys containing at least one of transition metals) and B, and the following [1] to
Those having the composition [4] are preferred.

[1] A rare earth element mainly composed of Sm and C
a transition metal mainly composed of o (hereinafter, referred to as a basic component)
Sm-Co alloy).

[2] R (where R is at least one of rare earth elements including Y), a transition metal mainly composed of Fe, and B as basic components (hereinafter, R-Fe-
B-type alloy).

[3] A rare earth element mainly composed of Sm and F
A material mainly composed of a transition metal mainly composed of e and an interstitial element mainly composed of N (hereinafter, referred to as an Sm-Fe-N-based alloy). [4] R (where R is at least one of rare earth elements including Y) and a transition metal such as Fe as basic components,
Those with a magnetic phase at the nanometer level (nanocrystalline magnets).

Representative examples of the Sm—Co alloy include SmCo ₅ and Sm ₂ TM ₁₇ (where TM is a transition metal).

Representative R-Fe-B alloys include Nd-Fe-B alloys, Pr-Fe-B alloys, and N-Fe-B alloys.
d-Pr-Fe-B-based alloy, Ce-Nd-Fe-B-based alloy, Ce-Pr-Nd-Fe-B-based alloy, in which part of Fe is replaced by another transition metal such as Co or Ni And the like.

[0057] Typical examples of the Sm-Fe-N based _alloy, Sm ₂ produced by nitriding a Sm 2 _{Fe 17} alloy
Fe ₁₇ N ₃ is mentioned.

The rare earth elements include Y, La, C
e, Pr, Nd, Pm, Sm, Eu, Gd, Tb, D
Examples thereof include y, Ho, Er, Tm, Yb, Lu, and misch metal, and one or more of these can be included. Examples of the transition metal include Fe, Co, and Ni, and one or more of these may be included. In order to improve magnetic properties, B, Al, Cu, Ga, Si, T
i, V, Ta, Zr, Nb, Mo, Hf, Ag, Zn,
P, Ge and the like can be contained.

The quenched ribbon (strip-shaped magnet material) 8 of the present invention obtained by the above-described manufacturing method has fine crystal grains, and as a result, excellent magnetic properties can be obtained.

Further, the powdered magnet material (magnet powder) of the present invention can be obtained by pulverizing such a rapidly cooled ribbon 8.

The method of pulverization is not particularly limited, and the pulverization can be performed using various pulverizers and crushers such as a ball mill, a vibration mill, a jet mill, and a pin mill. In this case, the pulverization is performed under a vacuum or reduced pressure (for example, 1 × 10 ⁻¹ to 1 × 10 ⁻⁶ Torr) or in an inert gas such as a nitrogen gas, an argon gas, a helium gas or the like to prevent oxidation. It can also be performed in such a non-oxidizing atmosphere.

Such a magnetic powder may be not only of the same composition but also a mixture of two or more different types of magnet powder. For example, a mixture of at least two of the above-mentioned compositions [1] to [4] can be used. In this case, the advantages of the respective magnet powders to be mixed can be obtained, and more excellent magnetic properties can be easily obtained.

The average particle size of the magnet powder is not particularly limited, but is preferably about 0.5 to 60 μm, and more preferably 1 to 40 μm for manufacturing a bonded magnet described later.
The degree is more preferred. Further, in order to obtain good moldability at the time of molding with a small amount of a binder resin as described later, it is preferable that the particle size distribution of the magnet powder is dispersed to some extent (varies). Thereby, the porosity of the obtained bonded magnet can be reduced, the mechanical strength of the bonded magnet can be further increased, and the magnetic properties can be further improved.

In the case of mixing two or more kinds of magnet powders having different compositions, the average particle size may be different for each composition of the magnet powder to be mixed. In the case of such a mixed powder, it is sufficient that at least one of the magnet powders having two or more different compositions is manufactured by the above-described method of the present invention.

When a bonded magnet is manufactured using the above-described magnet powder, such a magnet powder has a good bonding property with a bonding resin (wetting property of the bonding resin). High mechanical strength, heat stability (heat resistance),
Excellent corrosion resistance. Therefore, the magnet powder is
Suitable for manufacturing bonded magnets.

The magnet powder (powder-like magnet material) of the present invention is not limited to the one used for producing a bonded magnet.
For example, it goes without saying that it may be used for manufacturing a sintered magnet.

Next, the bonded magnet of the present invention will be described.

The bonded magnet of the present invention is obtained by bonding the above-mentioned magnet powder with a bonding resin.

As the binding resin (binder), either a thermoplastic resin or a thermosetting resin may be used.

Examples of the thermoplastic resin include polyamide (eg, nylon 6, nylon 46, nylon 66, nylon 610, nylon 612, nylon 11, nylon 12, nylon 6-12, nylon 6-66), and thermoplastic polyimide. , Liquid crystal polymers such as aromatic polyesters, polyphenylene oxide, polyphenylene sulfide, polyethylene, polypropylene, polyolefins such as ethylene-vinyl acetate copolymer, modified polyolefins, polyesters such as polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polybutylene terephthalate, and the like. Ether, polyetheretherketone, polyetherimide, polyacetal, etc.
Alternatively, copolymers, blends, polymer alloys, and the like mainly containing these may be used, and one or more of these may be used as a mixture.

Of these, polyamides and liquid crystal polymers and polyphenylene sulfides are preferred because they are particularly excellent in moldability and have high mechanical strength. These thermoplastic resins are also excellent in kneadability with magnet powder.

Depending on the type, copolymerization and the like of such a thermoplastic resin, a wide range of selections can be made, for example, one in which emphasis is placed on moldability, heat resistance, and mechanical strength. There is an advantage.

On the other hand, examples of the thermosetting resin include various epoxy resins such as bisphenol type, novolak type and naphthalene type, phenol resin, urea resin, melamine resin, polyester (unsaturated polyester) resin, polyimide resin and silicone resin. , Polyurethane resins, and the like, and one or more of these can be used as a mixture.

Among these, the moldability is particularly excellent, the mechanical strength is high, and the heat resistance is excellent.
Epoxy resins, phenol resins, polyimide resins and silicone resins are preferred, and epoxy resins are particularly preferred.
In addition, these thermosetting resins are kneadable with magnet powder,
Excellent in kneading uniformity.

The thermosetting resin used (uncured)
May be liquid at room temperature or solid (powder).

Such a bonded magnet of the present invention is manufactured, for example, as follows. Magnet powder, binding resin,
A composition for a bonded magnet (compound) containing an additive (antioxidant, lubricant, etc.) as necessary is produced, and a method such as compression molding, extrusion molding, or injection molding is performed using the bonded magnet composition. Thus, a desired magnet shape is formed in a magnetic field or in a non-magnetic field. When the binding resin is a thermosetting resin,
After molding, it is cured by heating or the like.

The content of the magnet powder in the bonded magnet was 82
９９99.5 wt%, preferably 90-99 wt%.
% Is more preferable. In particular, when the bonded magnet is manufactured by compression molding, the content of the magnet powder is preferably about 93 to 99.5 wt%,
More preferably, it is about 95 to 99% by weight.

If the content of the magnet powder is too small, the magnetic properties (particularly the magnetic energy product) cannot be improved, and if the content of the magnet powder is too large, the content of the binder resin becomes relatively small. And the moldability decreases.

Such a bonded magnet of the present invention is characterized by the characteristics of the quenched ribbon 8 as a raw material, the manufacturing conditions of the bonded magnet, the large content of the magnet powder contained in the bonded magnet, and the like. Exhibits excellent magnetic properties.

That is, the bonded magnet of the present invention has a coercive force
iHc is preferably at least 0.35 MA / m, more preferably at least 0.50 MA / m.

The bonded magnet of the present invention, particularly the bonded magnet formed in the absence of a magnetic field, has a magnetic energy product (BH) max of preferably 50 kJ / m ³ or more, more preferably 70 kJ / m ³ or more.

The shape, dimensions and the like of the bonded magnet of the present invention are not particularly limited. For example, regarding the shape, for example, a columnar shape, a prismatic shape, a cylindrical shape (ring shape), an arc shape, a flat plate shape, a curved plate shape, etc. And any size, from large to ultra-small, is possible.

[0083]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described.

(Example 1) The alloy composition was Nd ₁₀ Pr
_2.5 Fe _bal. Co ₆ Al ₃ Cu _1.5 Nb ₁
A master alloy ingot represented by Ga ₁ B ₅ (composition A) was cast. About 15 g of a sample was cut out from the ingot.

A quenched ribbon manufacturing apparatus 1 having the configuration shown in FIG. 1 was prepared, and the sample was placed in a quartz tube provided with a nozzle (circular orifice) at the bottom. After evacuating the chamber in which the quenched ribbon manufacturing apparatus 1 is housed, helium gas is introduced as an atmosphere gas, and the temperature is 21 ° C. and the pressure is 60 KPa.
Atmosphere gas.

Thereafter, the ingot sample in the quartz tube was melted by high-frequency induction heating, and this molten metal was heated at 1500 rp.
m (peripheral speed: 15.7 m / sec)
m, and jetted toward the peripheral surface of a cooling roll having a width of 20 mm by the differential pressure between the internal pressure of the quartz tube and the atmospheric pressure, to obtain a quenched ribbon of the alloy of the composition A.

The surface layer (roll peripheral surface) of the cooling roll is made of P
It was made of a d-8 wt% Ru-2 wt% Pt alloy. The thickness of the surface layer was 5 mm.

A horizontal surface is formed from the same material as the constituent material of the surface layer, and the melt of the composition A is gently dropped on the horizontal surface in a gas under the same conditions as the above-mentioned atmospheric gas, and the solidified product is solidified. (Volume: 0.01 cm ³ ), and the contact angle θ of the solidified product was measured by the method shown in FIG. 3 or FIG.
5 °. The measurement of the contact angle θ was performed optically using a projector.

When the maximum eccentricity ΔR of the peripheral surface of the cooling roll due to the rotation of the cooling roll was measured by a laser displacement meter, ΔR = 10 μm.

(Example 2) The surface layer (roll peripheral surface) of the cooling roll was made of Ni-10 wt% Ti-10 wt% Al-5 wt%.
A quenched ribbon was manufactured in the same manner as in Example 1, except that the Mo alloy was used (the thickness of the surface layer = 5 mm).

A horizontal surface is formed from the same material as the constituent material of the surface layer, and the molten metal of the composition A is gently dropped on the horizontal surface in a gas under the same conditions as the atmospheric gas, and the solidified product is solidified. (Volume 0.01 cm ³ ), and the contact angle θ of the solidified product was measured in the same manner as in Example 1.
°.

When the maximum eccentricity ΔR of the peripheral surface of the cooling roll due to the rotation of the cooling roll was measured by a laser displacement meter, ΔR = 12 μm.

Example 3 Nd ₁₁ Ce ₂ Sm ₁ Fe
_bal. Co ₄ Cu _1.5 Ga ₁ Ti _0.5 B ₆
A quenched ribbon was produced from a melt of the same composition using an ingot composed of (composition B), and the surface layer (roll peripheral surface) of the cooling roll was composed of a W-20 wt% Zr-3 wt% Nb alloy. A quenched ribbon was manufactured in the same manner as in Example 1 except that the thickness of the surface layer was 5 mm.

A horizontal surface is formed from the same material as the constituent material of the surface layer, and the molten metal of the composition B is gently dropped on the horizontal surface in a gas under the same conditions as the atmospheric gas, and the solidified product is solidified. (Volume 0.01 cm ³ ), and the contact angle θ of the solidified product was measured in the same manner as in Example 1.
Met.

When the maximum eccentricity ΔR of the peripheral surface of the cooling roll due to the rotation of the cooling roll was measured by a laser displacement meter, ΔR = 9 μm.

<Evaluation of Characteristics of Quenched Strip> The width w and thickness t of each of the quenched strips of Examples 1 to 3 were measured. In this measurement, each was measured at 20 measurement points for one quenched ribbon with a microscope, and the average value was obtained.

Next, the average crystal grain size of each quenched ribbon was measured from the results of microscopic observation of the structure by TEM.
Magnetic properties (coercivity iHc, magnetic energy product (BH) max)
Was measured by VSM.

The results of these measurements are shown in Table 1 below.

The dimensions (width w, thickness t) of each quenched ribbon
In each case, there was very little variation (mean value within ± 5%) depending on the measurement site, and dimensional stability was high.

For each quenched ribbon, the roll surface was observed with a scanning electron microscope (SEM), and image analysis was further performed.
When the area ratio occupied by giant dimples of 0 μm ² or more was examined, they were all extremely low.

[0101]

[Table 1]

As can be seen from Table 1, all of the quenched ribbons of the present invention of Examples 1 to 3 can achieve crystal grain refinement.
High magnetic properties are obtained.

Example 4 The quenched ribbon of Example 1 was pulverized in an inert gas by a pulverizer (Laika) to obtain a magnet powder having an average particle size of 16 μm. 0.0% by weight and hydrazine-based antioxidant 0.15
wt% and 0.05 wt% of a stearate (lubricant) were mixed, and this mixture was sufficiently kneaded (120 ° C. × 10 minutes) to prepare a composition (compound) for a bonded magnet.

Next, the compound is pulverized into granules, and the granules are weighed and filled in a mold of a press machine, and compression-molded (in a magnetic field-free state) at a material temperature of 130 ° C. and a pressure of 6 ton / cm ^2. Thus, a molded product was obtained. After release, the epoxy resin was cured by heating to obtain a cylindrical bonded magnet having a diameter of 10 mm and a height of 7 mm.

Example 5 The quenched ribbon of Example 2 was pulverized in an inert gas by a pulverizer (Raikai machine) to obtain a magnet powder having an average particle diameter of 20 μm. 0.5wt% and hydrazine antioxidant 0.1wt
% And 0.1 wt% of a stearate (lubricant) were mixed, and this mixture was sufficiently kneaded (120 ° C. × 10 minutes) to prepare a composition (compound) for a bonded magnet.

Next, the compound is pulverized into granules, and the granules are weighed and filled in a die of a press machine, and compression-molded (in a magnetic field-free state) at a material temperature of 130 ° C. and a pressure of 6 ton / cm ^2. Thus, a molded product was obtained. After release, the epoxy resin was cured by heating to obtain a cylindrical bonded magnet having a diameter of 10 mm and a height of 7 mm.

(Example 6) The quenched ribbon of Example 3 was pulverized in an inert gas by a pulverizer (Raikai machine) to obtain a magnet powder having an average particle size of 18 µm. 0.9wt% and hydrazine antioxidant 0.1wt
% And a stearic acid salt (lubricant) of 0.05 wt% were mixed, and the mixture was sufficiently kneaded (120 ° C. × 10 minutes) to prepare a bonded magnet composition (compound).

Next, the compound is pulverized into granules, and the granules are weighed and filled into a mold of a press machine, and compression-molded (without a magnetic field) at a material temperature of 130 ° C. and a pressure of 6 ton / cm ^2. Thus, a molded product was obtained. After release, the epoxy resin was cured by heating to obtain a cylindrical bonded magnet having a diameter of 10 mm and a height of 7 mm.

(Example 7) The magnet powder obtained in Example 4 and the magnet powder obtained in Example 6 were uniformly mixed at a weight ratio of 6: 4 to obtain a mixed magnet powder. This mixed magnet powder, 2.0 wt% of epoxy resin, and hydrazine antioxidant 0.15
wt% and 0.05 wt% of a stearate (lubricant) were mixed, and this mixture was sufficiently kneaded (120 ° C. × 10 minutes) to prepare a composition (compound) for a bonded magnet.

Next, the compound is pulverized into granules, and the granules are weighed and filled in a mold of a press machine, and compression-molded (in a magnetic field-free) at a material temperature of 130 ° C. and a pressure of 6 ton / cm ^2. Thus, a molded product was obtained. After release, the epoxy resin was cured by heating to obtain a cylindrical bonded magnet having a diameter of 10 mm and a height of 7 mm.

(Example 8) The magnet powder obtained in Example 4, the magnet powder obtained in Example 5, and the magnet powder obtained in Example 6 were uniformly mixed at a weight ratio of 2: 3: 5. A magnet powder was obtained.
This mixed magnet powder, 1.8 wt% of epoxy resin, 0.2 wt% of hydrazine-based antioxidant, and 0.1 wt% of stearic acid (lubricant) were mixed, and the mixture was thoroughly kneaded (120 ° C. × 10 minutes) to prepare a bonded magnet composition (compound).

Next, the compound is pulverized into granules, and the granules are weighed and filled in a mold of a press machine, and compression-molded (in a magnetic field-free state) at a material temperature of 130 ° C. and a pressure of 6 ton / cm ^2. Thus, a molded product was obtained. After release, the epoxy resin was cured by heating to obtain a cylindrical bonded magnet having a diameter of 10 mm and a height of 7 mm.

<Evaluation of Characteristics of Bonded Magnet> The magnetic properties (coercive force iHc, magnetic energy product (BH) max) of each of the bonded magnets of Examples 4 to 8 were measured by a DC self-recording magnetometer at a maximum applied magnetic field of 2 MA / m2. Was measured.

Further, with respect to these bonded magnets, 6
A constant temperature and humidity test was performed at 0 ° C. × 95% RH for up to 500 hours to examine corrosion resistance. This corrosion resistance was visually determined by the presence or absence of rust on the surface of the bonded magnet, and was marked with ○ when no rust was generated, and marked with △ when slight rust was observed. Those that were recognized were evaluated as x marks.

The results of these measurements are shown in Table 2 below. The content of the magnet powder in each bonded magnet (the total amount in the case of the mixed magnet powder) is also shown in Table 2 below.

[0116]

[Table 2]

As can be seen from Table 2, the bonded magnets of Examples 4 to 8 of the present invention all have a coercive force iHc of 0.35 MA.
/ m or more, and the magnetic energy product (BH) max 50 kJ / m ³ or more, with have excellent magnetic properties, are also excellent corrosion resistance.

Particularly, in Examples 7 and 8 using the mixed magnet powder, more excellent magnetic properties were obtained.

[0119]

As described above, according to the present invention, the cooling of the molten metal can be favorably performed by using the cooling roll having a suitable wettability on the peripheral surface. Therefore, the obtained quenched ribbon prevents crystal grains from becoming coarse and has high magnetic properties.

In particular, the difference in crystal grain size between the roll surface and the free surface of the quenched ribbon can be reduced, and the magnetic properties can be made uniform. Therefore, a permanent magnet having high mechanical strength and excellent magnetic properties and corrosion resistance can be provided.

Also, by reducing the maximum eccentricity of the peripheral surface of the cooling roll, it is possible to effectively prevent variations in the magnetic characteristics of the quenched ribbon, and to provide a permanent magnet having more excellent magnetic characteristics.

According to the present invention, such a magnet can be easily manufactured, and the productivity is high.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration example of an apparatus (a quenched ribbon manufacturing apparatus) for manufacturing a magnetic material of the present invention.

FIG. 2 is a cross-sectional side view showing a state near a collision site of a molten metal against a cooling roll in the apparatus shown in FIG.

FIG. 3 is a cross-sectional side view showing a method for measuring wettability of a peripheral surface of a cooling roll with a molten metal.

FIG. 4 is a cross-sectional side view showing a method for measuring wettability of a peripheral surface of a cooling roll with a molten metal.

FIG. 5 is a side view showing the maximum amount of eccentricity of the peripheral surface of the cooling roll accompanying rotation of the cooling roll.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Quenched ribbon manufacturing apparatus 2 Cylindrical body 3 Nozzle 4 Coil 5 Cooling roll 51 Base 52 Surface layer 53 Peripheral surface 6 Molten 7 Paddle 71 Solidification interface 8 Quenched ribbon 81 Roll surface 82 Free surface 9 Roll peripheral material 10 Horizontal surface 10 '' Face 11 solidified substance 12 peeling 13 huge dimple

Claims (13)

[Claims] 1. A method of manufacturing a magnet material in which a molten metal of a magnetic material is injected from a nozzle, impinges on a peripheral surface of a cooling roll rotating with respect to the nozzle, solidifies by cooling, and manufactures a ribbon-shaped magnet material. The metal material forming the peripheral surface of the cooling roll, the droplet of the molten metal is placed on a horizontal surface of the metal material, when solidified, the contact angle of the solidified product with the horizontal surface Is 70 ~
A method for producing a magnet material, wherein the angle is 170 °. 2. A magnet for producing a ribbon-shaped magnet material by injecting a molten metal of a magnet material from a nozzle in an atmosphere gas and colliding with a peripheral surface of a cooling roll rotating with respect to the nozzle to solidify by cooling. A method for producing a material, wherein a metal material constituting a peripheral surface of the cooling roll is configured by placing droplets of the molten metal on a horizontal surface of the metal material in a gas of the same type and the same pressure as the atmospheric gas, and solidified. When made, the contact angle between the coagulate and the horizontal surface is 70 to 170 °
A method for producing a magnet material, characterized in that: 3. The cooling roll has a peripheral speed of 1 to 60 m.
The method according to claim 1, wherein the magnetic material is used for the magnetic material. 4. The method according to claim 1, wherein the maximum eccentricity of the peripheral surface of the cooling roll due to the rotation of the cooling roll is not more than twice the average thickness of the obtained ribbon-shaped magnet material. Manufacturing method of magnet material. 5. The method according to claim 1, wherein the atmosphere gas is an inert gas. 6. The magnetic material according to claim 1, wherein R is R (where R is Y
The method according to any one of claims 1 to 5, wherein the alloy is an alloy containing at least one of rare earth elements containing 7. The method according to claim 1, wherein the magnet material is R (where R is Y
And TM (where TM is at least one of transition metals) and B
The method for producing a magnetic material according to any one of claims 1 to 5, wherein the alloy is an alloy containing: 8. A ribbon-shaped magnet material produced by the method for producing a magnet material according to claim 1. Description: 9. A powdered magnet material, wherein the magnet material according to claim 8 is pulverized into a powder. 10. A bonded magnet, wherein the powdered magnet material according to claim 9 is bonded with a bonding resin. 11. The content of the powdery magnetic material is 82.
The bonded magnet according to claim 10, wherein the content is up to 99.5 wt%. 12. The bonded magnet according to claim 10, wherein the coercive force iHc is 0.35 MA / m or more. 13. The magnetic energy product (BH) max is 50 kJ / m.
The bonded magnet according to any one of claims 10 to 12, wherein the number is ³ or more.