JP2002164205A - Composite bonded magnet, rotating machine, and magnet roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new high-performance composite bonded magnet, which has higher maximum energy product (BH)max than that of the conventional anisotropic sintered ferrite magnet, and is improved in magnetization or heat resistance. SOLUTION: This composite bonded magnet is composed substantially of R-T-B-based magnetic powder, containing an R2T14B intermetallic compound (where R and T respectively denote at least one kind of rare-earth element including Y and Fe or Fe and Co) as a main phase and has a mean crystal grain diameter of 0.01-0.5 μm, and is a sintered ferrite magnetic powder substantially having a magnetoplumbite type crystal structure, and a binder which binds the two kinds of magnetic powder to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wide range of magnet-applied product fields, for example, various rotating machines for automobiles or electric equipment, magnet rolls used for developing rolls in electrophotography and electrostatic recording, etc. Useful for loudspeakers, buzzers, magnets for attracting or generating magnetic fields, etc.
The present invention relates to a novel high-performance composite bonded magnet having (BH) max and further improved magnetizability or heat resistance. The present invention also relates to a high-performance rotating machine and a magnet roll configured using the novel high-performance composite bonded magnet.

[0002]

2. Description of the Related Art In recent years, poor magnetization and a measure of heat resistance, for example, a permeance coefficient: Pc = 1 to 2 (Pc = Bd / (−
Hd)), where Bd and Hd are the B and H values at the operating point on the BH demagnetization curve. Nd-Fe-B-based bonded magnets using magnetic powder having a main phase of Nd ₂ Fe ₁₄ B intermetallic compound having a large irreversible demagnetization rate evaluated in) are severe in recent miniaturization and high performance of magnet application products. Heat resistance and magnetization are not sufficient for the needs, and improvements are desired.

[0003] International Publication WO98 / 38654 discloses that at least one element selected from Sr, Ba, Ca and Pb, which contains a ferrite having a hexagonal structure as a main phase, and which always contains Sr. A, R is at least one element selected from rare earth elements (including Y) and Bi and always contains La, and is Co or C
When o and Zn are M, the total composition ratio of the metal elements of A, R, Fe and M is A: 1 to 13 at%, R: 0.05 to 10 at%, based on the total metal element amount, Fe:
A bond magnet using ferrite particles containing an oxide magnetic material having a composition of 80 to 95 atomic% and M: 0.1 to 5 atomic% is described. As a specific example, Sr _0.7 L
_{a 0.3 Fe 1 2-7 Co 0.3 O} 19 (Si to calcination before
0.2% by weight of O ₂ and 0.15% by weight of CaCO ₃ were added. After calcination of the calcined body having the composition of
It is described that the specific coercive force iHc of the obtained ferrite powder for a bonded magnet is 343.0 kA / m (4.31 kOe) after annealing for 5 minutes. However, (BH) max of an anisotropic bonded magnet produced by binding this ferrite powder with a binder is smaller than that of an anisotropic ferrite sintered magnet.

Japanese Patent Application Laid-Open No. 60-223095 discloses that a hard ferrite magnetic powder, a rare earth cobalt magnetic powder and a binder are blended at a predetermined ratio, kneaded and molded, and the temperature coefficient of magnetic flux density is -0.03 to -0.20. A field magnet bonded to a magnetic field device for a bubble memory device at% / ° C. is described. However, the field magnet has a temperature coefficient of the magnetic flux density adjusted to the above range, and thus has poor heat resistance and poor magnetization.

[0005]

Accordingly, an object to be solved by the present invention is to have a maximum energy product (BH) max exceeding that of the conventional sintered anisotropic ferrite magnet, and to further improve the magnetization or heat resistance. An object of the present invention is to provide an improved new high-performance composite bond magnet. Another object of the present invention is to provide a high-performance rotating machine and a magnet roll constituted by using the novel high-performance composite bond magnet.

[0006]

The composite type bonded magnet of the present invention which has solved the above-mentioned problems is an R ₂ T ₁₄ B intermetallic compound (R is at least one kind of rare earth element containing Y,
Is Fe or Fe and Co. R-T-B-based magnetic powder having an average crystal grain size of 0.01 to 0.5 µm having a main phase of
It is characterized by being substantially composed of a ferrite sintered magnetic powder having a substantially magnetoplumbite type crystal structure and a binder binding the two types of magnetic powder. The average particle size of the RTB-based magnetic powder contained in the composite bond magnet of the present invention is 1 to 1000 μm, the average particle size of the ferrite sintered magnetic powder is 2 to 1000 μm, and the Fe ²⁺ content is 0.10. weight%
High (BH) max and high iHc can be obtained in the following cases, and the magnetization and heat resistance can be improved.

Further, the composite type bonded magnet of the present invention is characterized in that
-TN-based magnetic powder, and (A _1-x R ' _x ) On [(Fe _{1- y My} ) ₂ O ₃ ] (atomic ratio) (A is Sr and / or Ba and R ′ Is at least one of the rare earth elements containing Y and La, Pr, Nd
And at least one selected from Ce,
M is Co or Co and Zn. ), 0.01 ≦ x
Ferrite sintered magnetic powder having a main component composition represented by ≦ 0.4, 0.005 ≦ y ≦ 0.04, and 5.0 ≦ n ≦ 6.4;
A high (BH) max, good magnetizability and particularly good heat resistance can be obtained when it is substantially composed of a binder that binds the magnetic powder of the species.

Further, the composite type bonded magnet of the present invention is characterized in that
-T-N magnet powder and _A'O · nFe 2 _{O 3} (atomic ratio) (A 'is Sr and / or Ba, 5.0 ≦ n ≦ 6.4
It is. ) And (A _1−x R ′ _x ) On · ([Fe _{1− y My} ) ₂ O ₃ ] (atomic ratio) (A is Sr and And / or Ba, R ′ is at least one rare earth element including Y, and La, Pr, Nd
And at least one selected from Ce,
M is Co or Co and Zn. ), 0.01 ≦ x
Ferrite sintered magnetic powder having a main component composition represented by ≦ 0.4, 0.005 ≦ y ≦ 0.04, and 5.0 ≦ n ≦ 6.4;
When it is substantially composed of a binder that binds various magnetic powders, it is possible to obtain an inexpensive composite bond magnet that has good magnetizability, has practical heat resistance, and is inexpensive.

[0009] The composite type bonded magnet of the present invention has radial anisotropy or polar anisotropy, and thus has high practicality. Also,
The rotating machine constituted by using the composite bond magnet of the present invention has high efficiency, and a high-definition image can be obtained by a copying machine equipped with a magnet roll constituted by using the composite bond magnet of the present invention. .

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS RTB-based magnetic powder used in the present invention
(R is at least one rare earth element including Y;
Is Fe or Fe and Co. ) Is anisotropic magnetic
There are powder and isotropic magnetic powder. Anisotropic magnetic powder is, for example, as follows
Manufactured. First, R₂T ₁₄B gold
An RTB-based alloy having a predetermined composition containing an intergeneric compound as a main phase
Average particle size 1-1000μm (Sympatec laser diffraction type particles
Diameter distribution measuring device: Measured by Heros Rhodes. ) Powder
Crush to the end. Then use hydrogen storage and dehydrogenation
Heat treatment: HDR (Hydrogenation Disproportionatio)
n Desorption Recombination)₂T
₁₄Oriented, average re-consolidation with B intermetallic compound as main phase
An aggregate composed of aggregates of fine crystal grains with a crystal grain size of 0.01 to 0.5 μm
An RTB alloy powder for an isotropic bonded magnet is obtained. Average reunion
Those with a crystal grain size of 0.01 μm are difficult to manufacture due to industrial production.
If it exceeds 0.5 μm, iHc and (BH) max significantly decrease. This R
The main component composition of the -TB based anisotropic magnetic powder is
R: 25-35%, B: 0.5% by weight to have properties
1.5%, Co 20% or less (more preferably 3-20%) and
And the remainder is preferably Fe.
Inclusion is acceptable. Also, if necessary, heat resistance and corrosion resistance
To increase T, Ga, Zr, Nb, Hf, T
at least selected from the group of a, Al, Si and V
It is preferable to substitute with one kind.
0.05 to 5% by weight per unit weight of TB magnetic powder
Is preferred. Isotropic magnetic powder is manufactured, for example, as follows
Is done. First, R₂T₁₄B intermetallic compound (R includes Y
At least one of the following rare earth elements, T is Fe or
Is Fe and Co. ) Is adjusted to the main phase composition
Rapidly quenched molten RTB-based alloy, substantially amorphous
Make quality flakes. Next, 550-8 in Ar gas atmosphere
Heat treated at 00 ° C and adjust average grain size to 0.01-0.5μm
I do. Those with an average crystal grain size of 0.01 μm are manufactured for industrial production
Is difficult, iHc and (BH) max are greatly reduced when the thickness exceeds 0.5 μm.
I do. Next, the average particle size is 1 to 1000 μm (Heros Rhodes
Measured by ) To obtain isotropic magnetic powder. etc
The main component composition of the isotropic magnetic powder has useful magnetic properties.
In terms of weight percent, R: 25-35%, B: 0.5-1.5%, Co
20% or less (more preferably 3 to 20%) and the balance Fe
And preferably contains other irreversible impurities.
Permissible. To increase heat resistance and corrosion resistance as needed
And part of T is Ga, Zr, Nb, W, Mo, Cu, H
f, Ta, Al, Si, and V
It is preferable to substitute at least one kind,
0.05 to 5% by weight per unit weight of isotropic RTB-based magnetic powder
It is preferred that

The sintered ferrite powder used for the composite bonded magnet of the present invention will be described below. Suitable sintered ferrite powders have a substantially magnetoplumbite-type crystal structure. Substantially having a magnetoplumbite-type crystal structure includes a phase having a magnetoplumbite-type crystal structure phase as a main phase, and it is preferable that the magnetic property manifesting phase comprises only the magnetoplumbite-type crystal structure phase.

The main component composition is (A _1−x R ′ _x ) On · ([Fe _{1− y My} ) ₂ O ₃ ] (atomic ratio) (A is Sr and / or Ba, and R ′ is Is at least one kind of rare earth element containing Y and always contains at least one kind selected from La, Pr, Nd and Ce;
Is Co or Co and Zn. ), 0.01 ≦ x ≦
0.4, 0.005 ≦ y ≦ 0.04 and 5.0 ≦ n ≦ 6.4
The reason for limiting the composition of the sintered ferrite magnetic powder having substantially the magnetoplumbite crystal structure will be described below. n
(Molar ratio) is preferably from 5.0 to 6.4, more preferably from 5.6 to 6.2, and particularly preferably from 5.8 to 6.0. When n exceeds 6.4, the formation of a different phase (such as α-Fe ₂ O ₃ ) other than the magnetoplumbite phase becomes remarkable, and iHc is greatly reduced. When n is less than 5.0, (BH)
max greatly decreases. The value of x is preferably 0.01 to 0.4,
0.1-0.3 is more preferable, and 0.15-0.25 is particularly preferable.
When x exceeds 0.4, (BH) max and iHc greatly decrease, and x becomes 0.01.
If it is less than the above, no addition effect is observed. R 'is La, P
Rare earth elements (including Y) other than r, Ce and Nd are allowed to be inevitably contained. La as a raw material of R ′,
It is inexpensive and preferable to use at least two kinds of mixed rare earth oxides or hydroxides selected from Pr, Ce and Nd. To increase the saturation magnetization, L occupied by R '
at least one selected from a, Pr, Ce and Nd
The proportion of the species is preferably at least 50 atomic%, more preferably
The content is preferably at least 70 at%, more preferably at least 95 at%. In particular, except for the inevitable R 'component,
Is most preferably La. In the composite bond magnet of the present invention, when importance is attached to heat resistance, it is preferable to select Co as M. Co and Zn as M
Is selected, the proportion of Co in M is preferably at least 50 at%, more preferably at least 70 at%, and particularly preferably at least 90 at%. If the ratio of Co to M is less than 50 atomic%, iHc is greatly reduced and heat resistance is deteriorated. In the composite bond magnet of the present invention,
When importance is placed on high residual magnetic flux density Br and (BH) max, Co and Zn are selected as M, and the ratio of Co in M is preferably 10 to 70 atomic%, more preferably 15 to 50 atomic%. Is more preferred. If the ratio of Co is less than 10 atomic%,
iHc and (BH) max are remarkably reduced, and if it exceeds 70 atomic%, the effect of Zn to improve Br and (BH) max is extremely small. In order to realize the purpose of the charge compensation, ideally, a relationship of y = x / (2.0n) needs to be established between y and x.
It is preferable that the ratio is not less than /(2.6n) and not more than x / (1.6n), since the effect of the charge compensation is not substantially impaired. For example, R
= La and M = Co the ideal charge compensation is La
^It can be treated as being canceled by ³⁺ and Co ²⁺ . When the value of y deviates from x / (2.0 n), it is determined that the Fe ³⁺ of the Fe site in the magnetoplumbite phase of the anisotropic ferrite sintered magnetic powder becomes Fe ²⁺ and the charge compensation is performed. . Further, from a comparison of Examples 1 to 3 described later, it was found that heat treatment in an excess oxygen atmosphere can significantly improve iHc, reduce Fe ²⁺ , and improve heat resistance of the composite bonded magnet. In order to increase iHc (heat resistance), the content of Fe ²⁺ is preferably set to 0.005 to 0.10% by weight, more preferably 0.01 to 0.07% by weight. It is difficult for industrial production to reduce the content of Fe ²⁺ to less than 0.005% by weight, and if the content of Fe ²⁺ exceeds 0.10% by weight, the effect of improving iHc is reduced. In a typical example, y
Is preferably 0.005 to 0.04, and more preferably 0.01 to 0.03. In the sintered ferrite magnetic powder having the main component composition, the R ′ concentration at the crystal grain boundaries tends to be higher than the R ′ concentration in the crystal grains. In particular, n = 5.7-6.2, x =
0.15 to 0.3 and 1.0 <x / 2ny ≦ 1.3, more preferably
R ′ excess composition of 1.05 ≦ x / 2ny ≦ 1.25, and C
The aO content to 0.5 to 1.5 wt%, 0 to SiO ₂ content.
High (BH) max and high iHc at 25-0.55% by weight
And the tendency that the R ′ concentration in the crystal grain boundaries is higher than the R ′ concentration in the crystal grains becomes remarkable.

The ferrite sintered magnetic powder used in the present invention has a main component composition of A'O.nFe ₂ O ₃ (atomic ratio) (A 'is Sr and / or Ba, and n (molar ratio) =
5.0 to 6.4. The main components represented by ()) are highly practical.

Beyond conventional anisotropic ferrite sintered magnets
In order to have (BH) max, the main component composition is (A _1-x R ′)
_x ) On [n ((Fe _1-y M _y ) ₂ O ₃ ] (atomic ratio) ferrite sintered magnetic powder and a main component composition of A′O.nFe ₂
O 3 and sintered ferrite magnetic powder _(atomic ratio) of 50 to 100: 5
It is preferable to mix them in a weight ratio of 0 to 0 to obtain a composite type magnetic powder for bonded magnets. The advantages of using them in a mixture _A'O · nFe 2 _{O 3} magnetic powder _{(A 1-x R 'x} ) O · n
_{[(Fe 1-y M y} ) 2 O 3] compared to the magnetic powder (BH) max, iHc
Is low but cheap.

The average particle diameter of the ferrite sintered magnetic powder is 2 to 2.
The thickness is preferably 1000 µm (measured by Herros Rhodes), more preferably more than 10 µm and 300 µm or less, particularly preferably 30 to 100 µm. If the average particle size is less than 2 μm, the packing density will decrease significantly and (BH) max will decrease significantly. If the average particle size exceeds 1000 μm, the surface condition of the composite bonded magnet will deteriorate, making it applicable to applications with narrow magnetic gaps. A difficult case arises. The production of the sintered anisotropic ferrite magnetic powder used in the present invention is a production of “mixing of raw material powder → ferrite formation by calcination (solid phase reaction) → pulverization → molding in a magnetic field → sintering → pulverization → heat treatment → crushing”. It is practical to use a process. Alternatively, a manufacturing process of “mixing of raw material powder → ferrite formation by calcination (solid phase reaction) → pulverization → molding in a magnetic field → pulverization → sintering → heat treatment → crushing” is also useful. In the latter manufacturing process, the compact is pulverized to an average particle size of 2 to 1000 μm and sintered. “Crushing” is a process performed to improve the magnetic field orientation by dissolving the aggregation state after the heat treatment. If the aggregation is mild, “crushing” may be omitted. The calcination conditions are 1150-1300 ° C x 1
Preferably, it is 5 hours. If the calcination conditions are less than 1150 ° C. × 1 hour, ferrite formation will be insufficient, and if it exceeds 1300 ° C. × 5 hours, the calcined material will be hard and the pulverizability will deteriorate. Coarse pulverization and fine pulverization are performed by arbitrarily combining known pulverizers. It is practical to use a dry or wet type attritor, ball mill, vibrating mill or the like. Composite type bonded magnet iHc
And to increase the (BH) max the average particle size of the finely ground powder is 0.4
To 0.9 μm (measured by an air permeation method), more preferably 0.6 to 0.8 μm. The average crystal grain size in the c-axis direction of the finally obtained anisotropic ferrite sintered magnetic powder can be made to be 2 μm or less, preferably 1 μm or less by making the finely pulverized average particle diameter. Next, molding in a wet magnetic field or molding in a dry magnetic field is performed. Molding in a magnetic field at room temperature 39
While applying a magnetic field of 7.9 to 1193.7 kA / m (5 to 15 kOe), 0.35
It is preferable to carry out at a molding pressure of about 0.45 ton / cm ² . The density of the molded body thus obtained is 2.6 to 3.2 Mg / m ³ (g / cm
³ ) about. Next, the compact is sintered at 1180 to 1230 ° C. for 1 to 5 hours. If the sintering condition is less than 1180 ° C. × 1 hour, the density of the sintered body does not increase sufficiently and the (BH) max decreases, and
If the time is exceeded, the crystal grains become coarse and the decrease in iHc becomes remarkable. Next, if necessary, the sintered body is pulverized, and then sieved or air-classified to adjust the particle size distribution and the average particle size to predetermined values. Next, heat treatment is performed. Although iHc can be increased by air heat treatment, the oxygen partial pressure (PO ₂ ) is preferably 0.02 MPa
(0.2atm) or more, more preferably 0.03MPa (0.3atm) or more,
Particularly preferably, heat treatment is performed at 750 to 950 ° C. for 0.5 to 5 hours in an excess oxygen atmosphere adjusted to 0.05 to 0.1 MPa (0.5 to 1 atm). When the oxygen partial pressure is 0.02 MPa or less, the improvement of iHc and the reduction of Fe ²⁺ are not sufficient, and when the oxygen partial pressure exceeds 0.1 MPa, the effect of the heat treatment is saturated. Heating condition of heat treatment is 750
If it is less than 0.5 ° C x 0.5 hours, iHc cannot be improved practically, and 950 ° C x
If it exceeds 5 hours, the aggregation of ferrite magnetic powder becomes remarkable and iHc,
(BH) max significantly decreases. When the anisotropic ferrite sintered magnetic powder contains an appropriate amount of SiO ₂ and CaO, a dense sintered body structure is obtained, and useful magnetic properties are obtained. S
iO ₂ is an additive that suppresses crystal grain growth during sintering,
The content is preferably 0.05 to 0.55% by weight, and 0.25 to 0.55%.
% Is more preferred. If the SiO ₂ content is less than 0.05%, uneven crystal grain growth during sintering becomes remarkable, iHc deteriorates,
If it exceeds 0.55%, the growth of crystal grains is excessively suppressed, and the improvement of the degree of orientation that proceeds with the growth of crystal grains becomes insufficient, so that Br,
(BH) max is greatly reduced. On the other hand, CaO is an element that promotes crystal grain growth, and the CaO content is 0.35 to 1.
5% is preferred, 0.4-1.2% is more preferred, 0.5-1.0
% Is particularly preferred. If the CaO content exceeds 1.5%, the crystal grain growth proceeds excessively during sintering, and iHc is greatly reduced. If the CaO content is less than 0.35%, a useful addition effect cannot be obtained, and the degree of orientation is insufficiently improved. (BH) max deteriorates. The iHc of the sintered ferrite magnetic powder at room temperature was 278.5 kA / m (3.5 kA / m).
Oe) or more, preferably 358.1 kA / m (4.5 kOe) or more, particularly preferably 437.7 kA / m (5.5 kOe) or more.
l content and the total Cr content as (Al ₂ O ₃ + Cr
_It is preferably 0.1 to 1% by weight in terms of ₂ O ₃ ),
More preferably, it is set to 0.5% by weight. When the content is less than this content, the effect of addition is practically not obtained. When the content is more than this content, the superiority to the conventional ferrite magnetic powder for bonded magnets is lost.

RT Constituting Anisotropic Composite Bonded Magnet
-The compounding weight ratio between the B-based magnetic powder and the ferrite sintered magnetic powder is as follows:
The ratio is preferably from 5 to 95:95 to 5, more preferably from 20 to 80:80 to 20. The compounding weight ratio of the RTB-based magnetic powder and the ferrite sintered magnetic powder constituting the isotropic composite-type bonded magnet is preferably 50 to 95:50 to 5, more preferably 60 to 95.
90:40 to 10 is more preferable. Beyond these compounding ratios exceed the anisotropic ferrite sintered magnet (BH) max
And it is difficult to improve the magnetization or heat resistance.

It is practical to use a known thermosetting resin, thermoplastic resin or rubber material as a binder constituting the compound. Particularly, a binder having a low viscosity is selected by applying an orientation magnetic field having a practical strength of 159.2 to 795.8 kA / m (2 to 10 kOe), preferably 238.7 to 477.5 kA / m (3 to 6 kOe). It is preferable to increase (BH) max of the anisotropic bonded magnet to be obtained. It is practical to employ a compression molding method in a magnetic field, an extrusion molding method in a magnetic field, or an injection molding method in a magnetic field as a molding method. Alternatively, heat the compound to 80-300 ° C. and then adjust the average spacing to 0.01-3 mm
Rolled into a sheet through the gap between the twin rolls adjusted to the above. Next, while maintaining the obtained sheet in the heated state, 159.2 to 795.8 kA / m along the thickness direction of a predetermined portion of the sheet.
(2-10 kOe) to give anisotropy by applying an orientation magnetic field,
Then cool. By performing this operation over the entire length of the sheet, an anisotropic sheet-like bonded magnet can be produced. If the heating temperature is lower than 80 ° C, the moldability is poor and it is difficult to impart anisotropy.If the heating temperature is higher than 300 ° C, thermal decomposition of the binder occurs (B
H) max is greatly reduced.

The shape and dimensions of the composite bonded magnet of the present invention are not particularly limited, but the outer diameter is 5 to 60 mm, the thickness defined by (outer diameter−inner diameter) / 2 is 0.3 to 3 mm, and the axial length is: 0.
A ring-shaped molded product of 3 to 50 mm (preferably one having radial or polar anisotropy) is rich in practicality. The shape and dimensions of the anisotropic bonded magnet having radial or polar anisotropy for magnet roll use are not particularly limited, but the outer diameter is 10 to 60 mm, and the axial length is 200 to 3
Forming into a cylindrical shape with a length of 50 mm and (length / outer diameter) ≧ 5 is rich in practicality. For use in small copiers and printers, the outer diameter is preferably 10 to 30 mm, particularly 10 to 20 mm, and a small diameter of (axial length / outer diameter) ≧ 5 is preferred.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

(Example 1) [Anisotropic RTB-based magnetic powder] Nd₂Fe₁₄Intermetallic B
The alloy melt adjusted to the composition with the main phase as
Cast into. The obtained alloy ingot is placed in an argon gas atmosphere.
The sample was homogenized at 1100 ° C. for 20 hours to obtain a sample for HDR treatment.
Exhaust capacity of 640 liter / min as heat treatment furnace for HDDR treatment
For processing HDR using a furnace equipped with a rotary pump
2 kg of sample was introduced into the furnace, and then hydrogen was sufficiently absorbed at room temperature.
Was. Then, while maintaining a hydrogen atmosphere of 0.1 MPa (1 atm), 10
Heated to 840 ° C at a rate of ° C / min. Then at the same temperature
After holding for 3 hours, a dehydrogenation treatment was performed for 45 minutes. Furnace after dehydrogenation
The inside was replaced with an argon atmosphere and cooled to room temperature. Obtained
Crushed sample, the average particle size is 150μm (Heros Rhodes
Measured by ), Nd having an average recrystallized grain size of 0.09 μm
₂(Fe, Co)₁₄B consists essentially of recrystallized grains,
The composition of the main components is Nd_12.5Fe_bal.Co_1
1.6B_6.0Ga_1.0Was obtained. [SrLaCo anisotropic ferrite heat-treated in excess oxygen atmosphere
Sintered magnetic powder] SrCO₃Powder (Ba, C as impurities
a), α-Fe₂O₃Powder, La₂O₃Powder and
Co₃O₄Sr after calcination using powder_0.80La
_0.20Fe_11.70Co_0.20O_18.85In table
It was blended so as to obtain the main component composition to be obtained. Then said
SiO in weight ratio to the formulation₂Powder and CaCO₃powder
0.25% by weight and 0.20% by weight of powder are mixed and mixed
did. Next, it was calcined at 1300 ° C. for 2 hours in the air. Obtained
After crushing the calcined product, dry crushing with a roller mill
Obtained. Then, wet pulverization using an attritor
A powder containing finely pulverized powder having a diameter of 0.6 μm (by the air permeation method)
Got a rally. SrCO as sintering aid in the early stage of pulverization₃
Powder, SiO₂Powder, CaCO₃Powder, Al ₂O₃Powder
And La₂O₃Total weight of coarse powder charged into fine grinding
0.25%, 0.40%, 0.80%, 0.25%
% And 0.60%. According to the obtained finely pulverized slurry
Compression molding in a magnetic field of 795.8 kA / m (10 kOe) to obtain a compact.
Was. Next, the molded body is sintered at 1200 ° C for 2 hours in the atmosphere.
And the following composition with La / Co = 1.2 (La excess composition)
An anisotropic ferrite sintered magnet was obtained. (Sr_0.77La_0.23) O ・ 5.72 [(Fe
_0.983Co_0.017) ₂O₃] SiO₂Content: 0.40% by weight, CaO content: 0.57% by weight
%, (Al₂O₃+ Cr₂O₃(Al + C)
r) Content: 0.32% by weight The obtained sintered body was coarsely crushed and then dry coarsely crushed with a roller mill.
A coarse powder was obtained. Next, the coarse powder is sieved to 150 mesh under.
did. Next, the sieving powder is subjected to oxygen partial pressure: PO₂= 0.1MPa (1at
m) in an excess oxygen atmosphere at 890 ° C for 2 hours.
And cooled to room temperature. Next, the heat-treated powder is added to water.
Immersion, then heat the immersion to 80 ℃ to evaporate moisture
Was. The thus obtained anisotropic sintered ferrite magnetic powder (hereinafter referred to as
Later, it is referred to as SrLaCo-based ferrite sintered magnetic powder-1. ) Average grain
The diameter was 55.4 μm (according to Heros Rhodes).
Fe per unit weight of SrLaCo-based ferrite sintered magnetic powder-1
²⁺The content was analyzed to be 0.05% by weight.
Fe is all Fe³⁺Met. [Anisotropic bonded magnet] Prepared anisotropic RTB-based magnetic powder
And SrLaCo-based ferrite sintered magnetic powder-1 at a weight ratio of 80/20
It was put into a stirrer and mixed. Then, the mixed magnetic powder: 10
0 parts by weight, liquid epoxy resin: 2.8 parts by weight, curing agent (DD
S; diaminodiphenylsulfone): 0.7 parts by weight
And methyl ethyl ketone (boiling point 79.5
° C): 2.8 parts by weight were weighed and charged into a stirrer. Next
And stirred at 20 rpm for 20 minutes to form a slurry. Got
Slurry (compound) allows orientation magnetism at room temperature
Field strength: 477.5 kA / m (6 kOe) and molding pressure: 784 MPa
(8 tons / cm²The compression molding was performed in a wet magnetic field under the conditions of (1). Get
The molded body was heated at 85 ° C. for 1 hour to remove the solvent,
Heat-cured at 0 ° C for 2 hours and anisotropic composite type bond magnet shown in Table 1.
Stone No.1 was obtained. Next, the anisotropic RTB-based magnetic powder
SrLaCo ferrite sintered magnetic powder-1 and 50/50 and 20/80
Same as No. 1 except that they were blended by weight ratio
To produce anisotropic composite bond magnets Nos. 2 and 3 in Table 1.
did. Next, assuming practical built-in magnetization,
After demagnetizing each bond magnet by AC, BH tracer
Magnetized at 20 ° C, magnetizing magnetic field strength: 795.8 kA / m (10 kOe), iH
c, (BH) max was measured. Next, the bond magnets of Nos.
The magnetization of the stone was defined by the following equation and evaluated. (Magnetization) = (Br_5kOe) / (Br_50kOe) X 100
(%) Br_5kOe: When the magnetizing magnetic field strength is 397.9 kA / m (5 kOe)
Br value of Br_50kOe: When the magnetizing magnetic field strength is 3979 kA / m (50 kOe)
Next, the permeance coefficient of each of the bonded magnets Nos.
(Pc) is 2; (thickness in magnetization direction) / (diameter) = 0.7 machine
processed. Then at 20 ° C at 2387.4 kA / m (30 kOe)
It was magnetized and the total magnetic flux (Φ) was measured. Next magnetized No.1
Each of the bonded magnet samples Nos. 1 to 3 was taken at 40 ° C, 45 ° C, 50 ° C,
55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃
℃, 100 ℃, 105 ℃, 110 ℃, 115 ℃, 120 ℃, 125 ℃, 130 ℃
℃, 135 ℃ and 140 ℃ for 1 hour, then to room temperature
And cooled. Next, measure the total magnetic flux (Φ ') of each sample
And the rate of change of the total magnetic flux defined by the following equation (irreversible demagnetization
Rate) reaches 5%, and the heat-resistant temperatures of No. 1 to 3 are evaluated.
Valued. (Irreversible demagnetization rate) = (Φ−Φ ′) / (Φ) × 100 (%) The above results are shown in Table 1.

Example 2 [SrLaCo-based anisotropic ferrite heat-treated in air atmosphere]
Sintered magnetic powder] Oxygen partial pressure: PO_Two= 0.02MPa (0.2atm) atmosphere
Same as Example 1 except that heat treatment was performed at 890 ° C. for 2 hours in an atmosphere.
Thus, the main component composition is (Sr_0.77L
a_0.23) O ・ 5.72 [(Fe_0.983Co
_0.017) ₂O₃] And SiO₂Content: 0.41
Wt%, CaO content: 0.55 wt%, (Al₂O₃+ C
r₂O₃(Al + Cr) content: 0.33 weight
%, Fe per unit weight²⁺Content = 0.08% by weight, etc.
Fe is all Fe³⁺Having an average particle size of 57.2 μm.
Anisotropic ferrite sintered magnetic powder (hereinafter SrLaCo-based ferrite
It is called sintered magnetic powder-2. ) Got. [Anisotropic bonded magnet] Anisotropic RTB based magnet of Example 1
Powder: 20 parts by weight and SrLaCo ferrite sintered magnetic powder-2: 80
Parts by weight were mixed. This mixed magnetic powder: 100 parts by weight, liquid
Poxy resin: 2.8 parts by weight, DDS: 0.7 parts by weight,
Til ethyl ketone: 2.8 parts by weight are put into a stirrer and stirred
Then, a slurry was obtained. Other than using this slurry
An anisotropic bonded magnet was prepared and evaluated in the same manner as in Example 1.
did. The results are shown in No. 13 of Table 1.

(Example 3) [SrLaCo-based anisotropic ferrite sintered magnetic powder without heat treatment] The 150-mesh under sieved powder obtained in Example 1 was anisotropic ferrite-sintered magnetic powder (hereinafter referred to as SrLaCo-based ferrite). Sintered magnetic powder-3). The SrLaCo-based ferrite sintered magnetic powder-3 had a Fe ²⁺ content of 0.11% by weight, and all other Fe contained were Fe ³⁺ . [Anisotropic bonded magnet] Anisotropic RTB-based magnetic powder of Example 1: 20 parts by weight and SrLaCo-based ferrite sintered magnetic powder-3: 80
Parts by weight were mixed. This mixed magnetic powder: 100 parts by weight, liquid epoxy resin: 2.8 parts by weight, DDS: 0.7 parts by weight, and methyl ethyl ketone: 2.8 parts by weight were charged into a stirrer and stirred to obtain a slurry. An anisotropic bonded magnet was prepared and evaluated in the same manner as in Example 1 except that this slurry was used. The results are shown in No. 23 of Table 1.

(Example 4) [Sr-based anisotropic ferrite heat-treated in excess oxygen atmosphere]
Sintered magnetic powder] Sr-based anisotropic ferrite manufactured by Hitachi Metals, Ltd.
Powder of sintered magnet (trade name: YBM-6BF)
Crushed and then sieved to 150 mesh ant. Then oxygen partial pressure:
PO _Two820 ℃ × 3 in an atmosphere of excess oxygen of 0.1MPa (1atm)
Heat treated for an hour and then cooled to room temperature. Next to underwater
Dip the heat-treated powder, then heat the dipped material to 80 ° C
After evaporating the water, the mixture was cooled. Thus the main component set
SrO.6Fe ₂O₃(Atomic ratio), average
Anisotropic ferrite sintered magnetic powder with a particle size of 65 μm (hereinafter Sr-based
Ferrite sintered magnetic powder. ) Was prepared. [Anisotropic bonded magnet] Anisotropic RTB based magnet of Example 1
Powder: 50 parts by weight, SrLaCo ferrite sintered magnetic powder-1: 30
Parts and Sr-based ferrite sintered magnetic powder: 20 parts by weight
Was. This mixed magnetic powder: 100 parts by weight, liquid epoxy resin: 2.8
Parts by weight, DDS: 0.7 parts by weight, and methyl ethyl keto
: 2.8 parts by weight is put into a stirrer, stirred, and the slurry is
Obtained. Same as Example 1 except that this slurry was used
To produce an anisotropic bonded magnet and evaluated. Table of results
No. 32 of No. 1 is shown.

Comparative Example 1 Anisotropic RTB of Example 1
System magnetic powder: 100 parts by weight, liquid epoxy resin: 2.8 parts by weight, DD
0.7 parts by weight of S and 2.8 parts by weight of methyl ethyl ketone were charged into a stirrer and stirred to obtain a slurry. An anisotropic bonded magnet was prepared and evaluated in the same manner as in Example 1 except that this slurry was used. The results are shown in No. 51 of Table 1. (Comparative Example 2) SrCO ₃ powder (Ba, Ca as impurities)
), Α-Fe ₂ O ₃ powder, La ₂ O ₃ powder and C
After calcination using o ₃ O ₄ powder (Sr _0.85 La
_0.15 ) O · 5.85 [(Fe _0.98 Co _0.02 ) ₂
O ₃ ], and mixed. Next, it was calcined in the air at 1200 ° C. for 2 hours. The obtained calcined product was coarsely crushed and then dry coarsely crushed with a roller mill to obtain a coarse powder. Next, fine powder having an average particle size of 1.2 μm (by an air permeation method) was obtained by a dry vibration mill. Next, PO ₂ = 0.02 MPa
Heat treatment at 820 ° C for 3 hours in the atmosphere of (0.2atm)
Then cooled to room temperature. Next, it was immersed in water and then dried to obtain a ferrite magnetic powder for a bonded magnet having an average particle diameter of 1.3 μm (by an air permeation method) (hereinafter, referred to as an SrLaCo-based ferrite bonded magnetic powder). Next, the anisotropic R-
80/2 of TB magnetic powder and SrLaCo ferrite bond magnetic powder
Mix at 0, 50/50 and 20/80 weight ratio respectively,
Seed mixed magnetic powder was produced. Each of these three types of mixed magnetic powder: 10
0 parts by weight, liquid epoxy resin: 2.8 parts by weight, DDS: 0.7 parts by weight, and methyl ethyl ketone: 2.8 parts by weight were charged into a stirrer and stirred to obtain three kinds of slurries. Using each of the slurries, an anisotropic bonded magnet was manufactured and evaluated in the same manner as in Example 1 thereafter. The results are shown in Table 1 Nos. 61 to 63.

[0025]

[Table 1] · SrLaCo system Fe ²⁺ content of the ferrite sintered magnet powder -1: Fe ²⁺ content of 0.05 wt% · SrLaCo ferrite sintered magnet powder -2: Fe ²⁺ content of 0.08 wt% · SrLaCo ferrite sintered magnet powder -3 ： 0.11% by weight

From Table 1, the following findings were obtained. (1) No. 3 of Example 1, Examples 2, 3 and No. 63 of Comparative Example 2
From the comparison, it can be seen that No. 3 containing SrLaCo-based ferrite sintered magnetic powder-1 heat-treated in an excess oxygen atmosphere has the highest (BH) max, iHc, magnetization and heat resistance temperature. In addition, from the comparison between Examples 2 and 3, it can be seen that (BH) max, iHc and heat resistance temperature are improved when the SrLaCo-based ferrite sintered magnetic powder-2 subjected to the heat treatment in the air is blended. In other words, heat treatment of sintered ferrite magnetic powder increases iHc without lowering the (BH) max of the anisotropic bonded magnet, and improves magnetizability. Thus, a rotating machine having high heat resistance can be formed. (BH) ma of anisotropic bonded magnet by heat treatment of ferrite sintered magnetic powder
x and iHc are improved by (BH) max, i of sintered ferrite magnetic powder.
This is because Hc is improved. It is considered that the effect of this heat treatment is effective in that the strain and micro defects introduced during the pulverization of the ferrite sintered magnetic powder are reduced or eliminated by the heat treatment, and that the Fe ²⁺ content is reduced. (2) In Example 1 and Comparative Example 2, when the RTB-based magnetic powder and the ferrite magnetic powder were compared at the same compounding ratio, N
o.1 is No.61, No.2 is No.62, No.3 is No.6
It can be seen that (BH) max, iHc, and heat-resistant temperature are all higher than those of 3. (3) No. 2 of Example 1, Example 4, and No. 6 of Comparative Example 2
From the comparison of 2, the RTB-based magnetic powder of Example 1 and the SrLaCo-based ferrite sintered magnetic powder-1 heat-treated in an excess oxygen atmosphere-1
And an Sr-based ferrite sintered magnetic powder heat-treated in an excess oxygen atmosphere at a specified ratio to produce an anisotropic bonded magnet
(BH) max exceeding No. 62 of Comparative Example 2 was obtained in No. 32, indicating that it is useful as an inexpensive anisotropic bonded magnet. (4) Each of the anisotropic bonded magnets of Examples 1 to 4 has better magnetizability and a higher heat resistance temperature than the conventional Nd-Fe-B based anisotropic bonded magnet of Comparative Example 1 and is therefore practical. It turns out that we are rich.

(Example 5) A No. 2 slurry of Example 1 was placed in a compression molding machine at room temperature, and a molding cavity having an outside diameter of 25 mm and an inside diameter (outer diameter of a mold core) of 22 mm was used. Was filled. Next, radial orientation magnetic field: 318.3 kA / m (4 kO
While applying e), molding was performed in a wet magnetic field at a molding pressure of 784 MPa (8 tons / cm ² ). The obtained molded body was heated to 80 ° C. to remove the solvent, and then heat-cured to obtain an outer diameter: 25 mm and an inner diameter: 22
mm, a ring-shaped radially anisotropic bonded magnet having an axial length of 15 mm was obtained. Symmetrical 8-pole magnetization was performed under the condition that the total magnetic flux was saturated in the circumferential direction of the outer diameter surface of the bonded magnet. Next, the surface magnetic flux density waveform in the center position in the axial direction and in the circumferential direction of the outer diameter surface was measured. The average value of the peak of each magnetic pole of the obtained surface magnetic flux density waveform was 0.21 T (2.1 kG). Comparative Example 3 A ring-shaped bonded magnet having radial anisotropy and subjected to symmetrical 8-pole magnetization (outer diameter: 25 mm, inner diameter) except that the slurry of Comparative Example 1 was used. :
22 mm, axial length: 15 mm). The average value of the peak of each magnetic pole of this ring-shaped bonded magnet is 0.19T (1.9kT).
G), which was lower than that of Example 5.

(Example 6) A No. 2 slurry of Example 1 was placed in a compression molding machine, and a molding die cavity having an outer diameter of 25 mm at room temperature and an inner diameter (outer diameter of the core of the die) of 22 mm was used. Was filled. Next, the polar anisotropic orientation magnetic field (symmetric 8 poles): 318.
While applying 3 kA / m (4 kOe), molding pressure: 784 MPa (8
Ton / cm ² ) in a wet magnetic field. 80
Deheated by heating to ℃, then heat-cured and outer diameter: 25m
Thus, a ring-shaped polar anisotropic bonded magnet having an inner diameter of 22 mm and an axial length of 15 mm was obtained. Symmetrical 8-pole magnetization was performed under the condition that the total magnetic flux was saturated along the anisotropy imparting direction of the bonded magnet. Next, the surface magnetic flux density waveform in the center position in the axial direction and in the circumferential direction of the outer diameter surface was measured. The average value of the peak of each magnetic pole in the obtained surface magnetic flux density waveform was 0.206 T (2.06 kG). (Comparative Example 4) In the same manner as in Example 6 except that the slurry of Comparative Example 1 was used, a ring-shaped bonded magnet having symmetrical 8-pole polar anisotropy and magnetized (outer diameter: 25 mm, Inner diameter: 22m
m, axial length: 15 mm). The average of each magnetic pole peak of this ring-shaped bonded magnet is 0.188T (1.88kG)
Which was lower than that of Example 6.

Using the ring-shaped bonded magnets produced in Examples 5 and 6 and Comparative Examples 3 and 4, each was assembled on the rotor side of a brushless motor to form a brushless motor. As a result of measuring the maximum efficiencies of each of these motors, the maximum efficiencies of the motors incorporating the ring-shaped bonded magnets of Examples 5 and 6 were almost the same and high, whereas those of Comparative Examples 3 and 4 were relatively high. It was found that the maximum efficiency of the motor incorporating the bonded magnet was low. 0.3mm average air gap between rotor and stator of each brushless motor
And

(Example 7, Comparative Example 5) [Sheet bonded magnet] Each of the four types of mixed magnetic powders shown in Table 2 was used, each mixed magnetic powder: 92.5 parts by weight, EEA resin (MB-
870): 5.2 parts by weight, dispersant (DH-37): 1 part by weight, lubricant (Slipax E): 0.5 part by weight, and silicone oil (KF968, manufactured by Shin-Etsu Chemical): 0.8 part by weight , Kneaded, and sized to prepare four types of compounds. Each of the RTN-based magnetic powders in Table 2 was produced in Example 1. No.101 SrLaCo in Table 2
Zn-based ferrite sintered magnetic powder is Sr _0.80 La after calcining.
_0.20 Fe _11.70 Co _0.10 Zn _0.10 O
_18.8 represented formulated to become the main component composition at _5, also prepared in the same manner as SrLaCo ferrite sintered magnet powder -1 of Example 1 except for not adding the Al ₂ O ₃ during milling This is an anisotropic ferrite sintered magnetic powder having an average particle size of 62.9 μm. SrLaCoZn ferrite sintered magnetic powder is (Sr
_0.77 La _0.23 ) O.5.72 [(Fe _0.983 Co
_0.0085 Zn _{0 . 0085} ) ₂ O ₃ ], a SiO ₂ content: 0.42% by weight, CaO
Content: 0.59% by weight, (Al + Cr) converted to (Al ₂ O ₃ + Cr ₂ O ₃ ) Content: 0.04% by weight, Fe ²⁺ =
The content of Fe was 0.05% by weight, and all other Fe was Fe ³⁺ . * SrLaCo-based ferrite sintered magnetic powder in Table 2 was produced in the same manner as in Example 1 except that Al ₂ O ₃ was not added at the time of pulverization. * SrLaCo ferrite sintered magnetic powder is (Sr
_0.77 La _0.23 ) O.5.72 [(Fe _0.983 Co
_0.017 ) ₂ O ₃ ].
iO ₂ content: 0.41% by weight, CaO content: 0.58% by weight, converted to (Al ₂ O ₃ + Cr ₂ O ₃ ) (Al + C)
r) Content: 0.05% by weight, average particle size 70.3 μm, Fe ²⁺
= 0.05% by weight, and all other Fe contained was Fe ³⁺ . Next, an extruder (not shown; kneading, set temperature of extrusion zone: 150 to 230) in which four compounds were sequentially heated
° C. ), And a parallel alignment magnetic field zone (applied magnetic field strength: 397.9 kA / m (5 kOe)) provided near the extrusion port of the extrusion molding machine
To extrude and solidify. Then axial length: 32
The sheet-like anisotropic bonded magnet 16 having a substantially U-shaped cross section and a thickness t of 2 mm was obtained as shown in FIG. [Magnet Roll] The magnet roll 23 shown in FIG. 1 was prepared and evaluated as follows. A concave groove 13 extending in the axial direction was formed in the developing magnetic pole portion of the cylindrical isotropic ferrite sintered magnet 17 fixed to the shaft 22. Next, the produced sheet-like anisotropic bonded magnets 16 were fixed to the grooves 13, respectively, to form magnet rolls 23 (Nos. 101 to 104 in Table 2). Since the concave portion 14 extends and penetrates in the axial direction of the sheet-like anisotropic bonded magnet 16, the air gap magnetic flux density distribution waveform immediately above the developing magnetic pole has two peaks. Magnet roll
The surface magnetic flux density Bo immediately above N ₁ pole along the axial direction of 23 was measured to obtain the results shown in Table 2. Bo (average value) in Table 2 is shown as a relative value. In the Bo measurement, a portion extending from both ends in the axial direction of the sheet-like anisotropic bonded magnet 16 to 10 mm toward the center in the axial direction was excluded, and the axial length was 300 mm (± 150 mm from the axial center).
mm). As a result, No. 101 of Example 7
Each of the 103 magnet rolls was a comparative example 5 (No. 11
It has a higher Bo (average value) than the magnet roll of 1), indicating high performance. The cylindrical magnet 17
Can be constituted by a conventional isotropic ferrite bonded magnet or anisotropic ferrite bonded magnet.

Although the thickness t of the sheet-like anisotropic bonded magnet of Example 7 is 2 mm, it is 159,2 to 795.8 kA / m (2 to 10 kO
e) If extrusion molding or calender roll molding is performed while applying a practical orientation magnetic field strength, a thickness having a (BH) max exceeding that of a conventional anisotropic ferrite sintered magnet: 0.01 to
A 3 mm sheet-like anisotropic bonded magnet can be produced.

[0032]

[Table 2]

Example 8 Nd having an average crystal grain size of 0.11 μm
₂ Fe ₁₄ B intermetallic compound as main phase, average particle size 210 μm
m (by Heros Rhodes) Nd-Fe-B-based isotropic magnetic powder and SrLaCo-based ferrite sintered magnetic powder-1 prepared in Example 1 were mixed at a weight ratio of 50/50. This mixed magnetic powder: 92.5 parts by weight, EEA resin (MB-870): 5.2 parts by weight, dispersant (DH-37): 1 part by weight, lubricant (Slipax E):
0.5 part by weight and silicone oil (KF968, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.8 part by weight is charged into a heating / pressing type kneader,
The mixture was kneaded and sized to obtain a compound. The compound was put into a heated extruder (not shown; kneading, set temperature of extrusion zone: 150 to 230 ° C.), extruded without a magnetic field, and solidified. Then cut to width: 3mm, thickness: 3
mm: an isotropic sheet-like bonded magnet having a length in the axial direction of 300 mm was obtained. (Comparative Example 6) Nd ₂ Fe ₁₄ B having an average crystal grain size of 0.11 μm
Nd-F having an average particle size of 210 μm containing an intermetallic compound as a main phase
The EB-based isotropic magnetic powder and the SrLaCo-based ferrite bond magnetic powder prepared in Comparative Example 2 were mixed at a weight ratio of 50/50. Using this mixed magnetic powder, a compound was prepared in the same manner as in Example 8, extruded, and cut to obtain an isotropic sheet-like bonded magnet having a width of 3 mm, a thickness of 3 mm and an axial length of 300 mm. Was. The average value of the surface magnetic flux density of the isotropic sheet-like bond of this comparative example was lower than that of the isotropic sheet-like bond magnet of Example 8 by about 0.003 T (30 G).

When each of the anisotropic ferrite sintered magnetic powders described in the above examples was subjected to X-ray diffraction, only the X-ray diffraction peak of the magnetoplumbite type crystal structure phase was observed.
It was found to have a magnetoplumbite type crystal structure.

In Examples 1 to 6, a case was described in which a slurry was prepared by using a liquid epoxy resin as a binder and compression-molded in a magnetic field, but the present invention is not limited to this. For example, if a compound is manufactured by using a thermoplastic resin such as polyamide resin as a binder, compression molding in a magnetic field or injection molding in a magnetic field can be performed at a high temperature to produce a high-performance composite bonded magnet, as well as compound and composite bonding. The magnets can be recycled, and the cost can be reduced.

In the compound used in the present invention, in addition to the magnetic powder and the binder, a dispersant (for example, a phenol type), a coupling agent (for example, a silane type coupling agent), a lubricant (for example, a wax), a plasticizer (for example, a magnetic powder). For example
DOP, DBP, etc.), an antioxidant or the like is added alone or in combination to improve moldability, oxidation resistance, strength, magnetic properties and the like. The total amount of these additives is preferably 3% by weight or less, more preferably 0.1 to 2% by weight.

[0037]

As described above, according to the present invention, the maximum energy product exceeding the conventional sintered anisotropic ferrite magnet is obtained.
It is possible to provide a new high-performance composite bonded magnet having (BH) max and further improved magnetizability or heat resistance. Further, it is possible to provide a high-performance rotating machine and a magnet roll configured by using the novel high-performance composite bond magnet.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an example of a magnet roll of the present invention.

[Explanation of symbols]

13 grooves provided in parallel with the axial direction, 14 concave parts, 15 convex parts,
16 sheet-like bonded magnets, 17 magnet roll base, 22 shafts, 23 magnet rolls.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22C 33/02 C22C 33/02 G 38/00 303 38/00 303D H01F 1/08 H01F 1/08 B ( 72) Inventor Hiroshi Kubota 5200, Sankajiri, Kumagaya-shi, Saitama Prefecture, Hitachi Metals, Ltd. Magnetic Materials Research Laboratory (72) Inventor Takashi Takami 5200, Sankajiri, Kumagaya-shi, Saitama Prefecture, Hitachi Metals, Ltd. Magnetic Materials Research Laboratory F-term (reference) 4K018 AA27 AB01 AC01 BA11 BA18 BB04 BD01 GA04 JA16 KA46 4K020 AA22 AC07 BB29 5E040 AA04 AA09 AB04 BB04 BB05 BD01 CA01 HB01 HB03 HB06 HB11 HB15 HB17 NN01 NN06 NN18

Claims (9)

[Claims] 1. An average crystal grain size having a main phase of R ₂ T ₁₄ B intermetallic compound (R is at least one kind of rare earth element including Y and T is Fe or Fe and Co). It is characterized by substantially comprising an RTB-based magnetic powder of 0.01 to 0.5 μm, a ferrite sintered magnetic powder having a substantially magnetoplumbite type crystal structure, and a binder binding the two types of magnetic powder. Composite type bonded magnet. 2. The average particle size of the RTB-based magnetic powder is 1 to 1000.
μm, and the average particle diameter of the ferrite sintered magnetic powder is 2 to 1000
2. The composite bonded magnet according to claim 1, wherein the composite bonded magnet has a particle size of μm and an Fe ²⁺ content of 0.10% by weight or less. 3. The ferrite sintered magnetic powder according to claim 1, wherein (A _1−x R ′ _x ) On · ([Fe _{1− y My} ) ₂ O ₃ ] (atomic ratio) (A is Sr and / or Ba. R ′ is at least one of rare earth elements including Y and La, Pr, Nd
And at least one selected from Ce,
M is Co or Co and Zn. ), 0.01 ≦ x
3. The composite bonded magnet according to claim 1, having a main component composition represented by ≤0.4, 0.005≤y≤0.04, and 5.0≤n≤6.4. 4. The ferrite sintered magnetic powder according to claim 1, wherein A′O.nFe ₂ O ₃ (atomic ratio) (A ′ is Sr and / or Ba and 5.0 ≦ n ≦ 6.4
It is. ) And (A _1−x R ′ _x ) On · ([Fe _{1− y My} ) ₂ O ₃ ] (atomic ratio) (A is Sr and And / or Ba, R ′ is at least one rare earth element including Y, and La, Pr, Nd
And at least one selected from Ce,
M is Co or Co and Zn. ), 0.01 ≦ x
3. The composite type bonded magnet according to claim 1, comprising a ferrite sintered magnetic powder having a main component composition represented by ≤0.4, 0.005≤y≤0.04, and 5.0≤n≤6.4. 5. The ratio of the RTB-based magnetic powder to the entire magnetic powder contained in the composite bonded magnet is 5 to 95% by weight, and the ratio of the ferrite sintered magnetic powder is 95 to 5% by weight.
The composite bonded magnet according to any one of claims 1 to 4, wherein 6. The composite bonded magnet according to claim 1, wherein radial or polar anisotropy is provided. 7. The composite bonded magnet according to claim 1, which has a sheet shape having a thickness of 0.01 to 3 mm. 8. A rotating machine comprising the composite bonded magnet according to claim 1. Description: 9. A magnet roll comprising the composite bonded magnet according to any one of claims 1 to 7.