JPH023214A - Manufacture of permanent magnet - Google Patents

Abstract

PURPOSE:To make a high performance permanent magnet at low cost by a method wherein an alloy made of each one kind of rare earth element, transition metal element and group IIIb element is melted and cast and the cast ingot is put into a hot working process at a specified temperature and then a magnetic phase is concentrated by removing a liquids phase of an R-rich phase which is a non-magnetic substance and finally a magnetic anisotropy is applied by mechanical orientation. CONSTITUTION:An alloy, which is made of one or more kinds of rare earth elements R out of Pr, Nd, Dy, Ce, La, Y and Tb, one or more kinds of transition metals M out of Fe, Co, Cu, Ag, Au, Ni and Zr and one or more kinds of group IIIb elements X out of B, Ga and Al, is melted and cast. The cast ingot is put into a hot working process mainly a hot press process at 500 deg.C or higher temperature. A liquid phase 14 of an R-rich phase 13 which is a non-magnetic substance is removed out of the basic components for concentrating a magnetic phase. With application of a magnetic anisotropy by mechanical orientation, a C-axis orientation rate is increased, a residual flux density Br is remarkably improved, crystal grains are made into fine ones and a coercive force iHc and the maximum energy product (BH)max are particularly increased. Furthermore, the magnet can be made at a low cost.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a novel method for producing a permanent magnet having magnetic anisotropy due to mechanical orientation, and in particular R (where R is at least one of the rare earth elements including Y). 1 type).

M (at least one transition metal element) and X
The present invention relates to a method for manufacturing a permanent magnet made of at least one group IIIb element.

[Prior art] Permanent magnets are one of the important electrical and electronic materials used in a wide range of fields, from various household electrical appliances to peripheral terminal equipment for large computers, and are becoming more and more compact in recent years. With the demand for higher efficiency, permanent magnets are also required to have increasingly higher performance.

A permanent magnet is a material that generates a magnetic field without supplying electrical energy from the outside, and a material with a large coercive force and a high residual magnetic flux density is suitable, contrary to a high permeability material.

Typical permanent magnets currently in use are Alnico cast magnets, Ba ferrite magnets, and rare earth-transition metal magnets.

In particular, R-C, which is a rare earth-transition metal magnet.

BACKGROUND ART A lot of research and development has been done on permanent magnets such as R-Fe-B permanent magnets because they provide high magnetic performance as permanent magnets with extremely high coercive force and energy product.

Conventionally, there are the following methods for manufacturing these rare earth-iron (transition metal)-based high-performance anisotropic permanent magnets.

(1) First, JP-A-59-48008, M, S
agava.

S, Fujimura, N, Togawa, H,Y
an+aioto and Y, Matsuura;J
, Appl, Phys, Vol., 55(8) 15Mar.
oh 1984. p2083゜ etc. has an atomic percentage of 8
A permanent magnet characterized by being a magnetically anisotropic sintered body consisting of ~301% R (where R is at least one kind of rare earth element including Y), 2~28% B, and the balance Fe is a powder metallurgy permanent magnet. It is disclosed that it is manufactured by method-based sintering.

In this sintering method, an alloy ingot is produced by melting and casting, and is pulverized to obtain magnet powder with an appropriate particle size (number of minus numbers). Magnetic powder is kneaded with a binder, which is a molding aid, and press-molded in a magnetic field to complete a molded product. The compact is sintered in argon at a temperature around 1100° C. for 1 hour and then rapidly cooled to room temperature.

After sintering, the permanent magnet is heat treated at a temperature of around 600°C to further improve its coercive force.

(2) Also, JP-A No. 59-211549 and R, V
, Lee; ^ppl, Phys, Lett, Vol.
4B(8), 15 April 1985゜p79
0 is a permanent magnet formed from fine pieces of melt-spun alloy ribbon with very fine crystalline magnetic powder and bonded together, said alloy being of the group consisting of neodymium, praseodymium, and mitsch metals. In a permanent magnet that is an alloy containing one or more rare earth elements selected from; a transition metal element; iron; and boron, fine particles are formed into the desired magnet shape by an adhesive distributed between them. The bonded particles are retained, and that the magnet moldings are magnetically isotropic and can be magnetized in any desired direction in a suitable magnetic field to form a bonded magnet. A bonded rare earth-iron magnet is disclosed, wherein the magnet has a grain compaction density of at least 80% of the alloy density and a residual magnetic energy product of at least 9 megagauss Oersted at saturation magnetization.

is disclosed.

This permanent magnet was made using a melt-spinning process, in which a quenched thin piece with a thickness of about 30 mm was made using a quenched ribbon manufacturing device used to manufacture amorphous alloys, and then the thin piece was turned into a magnet using a resin bonding method. Manufactured by resin bonding method.

In this resin bonding method using quenched thin strips using the melt spinning method, first, R
-Make a rapidly solidified ribbon of Fe-B alloy.

The obtained ribbon-like thin strip with a thickness of 30 μm has a diameter of 100 μm.
It is an aggregate of crystals with a diameter of 0 Å or less, and is brittle and easily broken. Since the crystal grains are distributed in the same direction, it is also magnetically isotropic. If this thin ribbon is crushed to an appropriate particle size, kneaded with resin, and press-molded, it will produce approximately 85% of
Filling by volume % is possible.

(3) Furthermore, JP-A-60-100402, R,
W, Lee; Appl, Phys, Lett;
Vol, 4B(8), 15 April 1985
゜p790 describes a method of making an anisotropic permanent magnet by high-temperature treatment, in which the permanent magnet is iron-rare earth metal,
The method involves high temperature processing of an amorphous to finely crystalline solid material containing iron, neodymium and/or praseodymium and boron to produce a plastically deformed object with a fine grained microstructure; Disclosed is a method for producing a permanent magnet, comprising cooling and adjusting the duration of the high temperature treatment and the cooling rate such that the resulting object is magnetically anisotropic and exhibits permanent magnetic properties. has been done.

The manufacturing method of these magnets is to process the ribbon-like quenched ribbon or flake in the above (2) by a method called a two-step hot pressing method in a vacuum or an inert atmosphere to obtain a dense and anisotropic R -F , e-B magnet is obtained.

In this pressing process, uniaxial pressure is applied, the axis of easy magnetization is oriented parallel to the pressing direction, and the alloy becomes anisotropic.

In addition, the crystal grains of the ribbon-like thin strip produced by the initial melt spinning method are made smaller than the grain size at which they exhibit the maximum coercive force, to avoid coarsening of the crystal grains during the subsequent hot pressing. Allow the particles to grow to the optimum particle size.

(4) Finally, in Japanese Patent Application Laid-open No. 62-276803,
R (However, R is at least one rare earth element including Y
species) 8 atom% to 30 atom%, B2 atom% to 28 atom%,
After melting and casting an alloy consisting of 50 atomic% or less of Co, 115 atomic% or less of Co, and the balance consisting of iron and other impurities unavoidable in manufacturing, the cast ingot is hot worked at a temperature of 500°C or higher to reduce crystal grains. A rare earth-iron permanent magnet is disclosed, which is characterized by making the cast alloy magnetically anisotropic by making the cast alloy finer and orienting its crystal axis in a specific direction.

[Problems to be Solved by the Invention] The conventional methods for manufacturing R-Fe-B permanent magnets described in (1) to (4) above have the following drawbacks.

The manufacturing method for permanent magnets in (1) requires that the alloy be made into powder, but since R-Fe-B alloys are highly active against oxygen, making them into powder will cause additional oxidation. The oxygen concentration in the sintered body inevitably increases.

Also, when molding the powder, a molding aid, such as zinc stearate, must be used, which is removed beforehand during the sintering process; This carbon remains in the form of carbon, which is undesirable because it significantly reduces the magnetic performance of R-Fe-B.

The molded body after press molding with the addition of a molding aid is called a green body, which is extremely brittle and difficult to handle.

Therefore, a major drawback is that it takes a considerable amount of effort to arrange them neatly in the sintering furnace.

Because of these drawbacks, - R-Fe-B
Not only does the production of sintered magnets of this type require expensive equipment, but the production method has poor production efficiency, resulting in an increase in the production cost of the magnets. Therefore, it is not possible to take advantage of the advantages of R-Fe-B magnets, which have relatively low raw material costs.

Next, the method for manufacturing permanent magnets in (2) and (3) is as follows:
A vacuum melt spinning device is used, which
Currently, it is very inefficient and expensive.

The permanent magnet (2) is isotropic in principle, so it has a low energy product, and the squareness of the hysteresis loop is also poor, so it is disadvantageous in terms of temperature characteristics and usage.

The method (3) for manufacturing permanent magnets is a unique method of using hot press in two stages, but it cannot be denied that it is inefficient when considering actual mass production.

Furthermore, in this method, at high temperatures, for example, 800'C or higher, the crystal grains become significantly coarsened, and as a result, the coercive force Inc is extremely reduced, making it impossible to produce a practical permanent magnet.

The method (4) for manufacturing permanent magnets simplifies the manufacturing process the most because it does not involve a powder process and only requires one step of hot pressing, but in terms of performance it is inferior to (1) to (3). There was a problem that it was slightly inferior.

The present invention is intended to solve the above-mentioned drawbacks of the prior art, particularly the drawback (4) in terms of performance of permanent magnets, and its purpose is to provide a high-performance, low-cost manufacturing method for permanent magnets. It's about doing.

[Means for Solving the Problems] The method for manufacturing a permanent magnet of the present invention relates to a method for manufacturing a rare earth element (R)-transition metal element (M)-group IIIb element (X) system permanent magnet, Specifically, R(Pr,
at least one rare earth element selected from Nd, Dy, Ce, La, Y, Tb) -M (Pe, G
o, Cu.

At least one selected from Ag, Au, old, and Zr
transition metals) -X (at least one group IIIb element selected from B, Ga, and AI) is used as a basic raw material component, an alloy having the basic component is melted and cast, and then a cast ingot is produced. By hot processing at a temperature of 500°C or higher and excluding the liquid phase of the non-magnetic R-rich phase from the basic components, the magnetic phase is concentrated and the magnetic anisotropy is improved by mechanical orientation. This is a method for producing a permanent magnet, which is characterized by providing a permanent magnet.

Furthermore, specifically, 12 to 25% R2 in atomic percentage
Using 65 to 85% M and 3 to 1O% By excluding the liquid phase of the non-magnetic R-rich phase from the components, the atomic percentage of
A method for producing a permanent magnet, characterized by concentrating a magnetic phase consisting of 72 to 87% M and 3 to 10% The method for producing the permanent magnet described above has a diameter of 0.31z to 150 M and a ratio of the R-rich phase of 10% or less (excluding OS).

In addition, the basic ingredients of the raw material are 12 to 25% Pr, 65 to 85% Fe, and 3 to 10% B in terms of atomic percentage, and the alloy containing these basic ingredients is melted and cast, and then the cast ingot is heated at 500°C or higher. By hot working at a temperature to exclude the liquid phase of the non-magnetic R-rich phase from the basic components, P r of 10 to 18X in atomic percentage, 72 to 8
A magnetic phase consisting of 7% Fe and 3 to 10% B is concentrated so that the crystal grain size is 0.3 μm to 150- and the ratio of the R-rich phase is 10% or less (not including 0%), This is a method for producing a permanent magnet characterized by imparting magnetic anisotropy through mechanical orientation.

Furthermore, the above method for producing a permanent magnet includes hot processing a cast ingot and then heat treatment, and the above method for producing a permanent magnet, which includes performing one type of hot processing selected from hot pressing, hot rolling, and extrusion. be.

[Function] The present inventors evaluated a number of R:Pe-B based cast alloys and found that a high coercive force could be obtained by applying appropriate heat treatment to the Pr-Fe-B based alloy, and further, Based on this alloy, the present invention was achieved as a result of research into the effects of mechanical orientation treatment using hot pressing and the effects of additive elements on improving magnetic properties.

That is, the present invention provides R(Pr, Nd, Dy, Ce, La,
At least one rare earth element selected from Y, Tb) -M (Pe, Co, Cu, Ag, Au,
-X (at least one or more group IIIb elements selected from B, Ga, and AI) as the basic raw material component, and the basic component and The magnetic phase is concentrated by melting and casting the alloy, and then hot working the cast ingot at a temperature of 500°C or higher to exclude the liquid phase of the non-magnetic R-rich phase from the basic components. , a method for producing a permanent magnet characterized by imparting magnetic anisotropy through mechanical orientation, which does not include the powder steps of casting, hot working, and heat treatment.
A magnet with high performance comparable to conventional methods can be obtained.

In the present invention, FIGS. 3(a)-(
The permanent magnet of the present invention is manufactured by following the process shown in C). As shown in Figure 3 (b), the initial R-M-X is processed into a non-magnetic R-rich liquid phase by hot pressing at a temperature of 500°C or higher. As a result of extrusion to the outside, the number of ferromagnetic phase particles increases, and only the particle phase becomes fine and oriented, increasing the magnetic properties of the magnet.

In addition, when manufacturing magnets, R2F is used as a ferromagnetic material.
e 14 B (atomic ratio” R11,7Fe82.4
B is adjusted to a target of 5.9 (atomic percentage), but when there is a large amount of R, the R-rich phase acts as a non-magnetic substance, and when there is a large amount of B, the B-rich phase acts as a non-magnetic substance.

In the present invention, the R-rich phase is made non-magnetic by initially blending a large amount of R, but it goes without saying that if there is a large amount of B, the B-rich phase is made non-magnetic as well.

Next, the reasons for limiting R, M, and X of the basic raw material components in the present invention will be described.

R: 12-25% If it is less than 12%, the amount of R-rich phase will be small and it will be easy to crack, making hot working difficult. Moreover, if it exceeds 25%, the amount of the non-magnetic phase increases too much and the concentration of the magnetic phase becomes insufficient, resulting in a decrease in performance, so it was determined as described above.

M: 65-85% If it exceeds 85%, the amount of R-rich phase will be small and hot processing will be difficult, and if it is less than 65%, the amount of non-magnetic phase will increase too much and the concentration of magnetic phase will be insufficient, resulting in poor performance. was determined as above.

X: 3 to 10% If it is less than 3%, the amount of magnetic phase will be too small and high performance will not be obtained. Moreover, if it exceeds 10%, the amount of non-magnetic phase increases and hot working becomes difficult, so it was determined as above.

The component value obtained after processing the raw material basic components specified as above by adapting them to the present invention is R: 10 to 18%.
, Mnear: 2 to 87%, and X: 3 to 10% are composition ranges in which high magnetic properties can be obtained.

In addition, in the present invention, the crystal grain size is set to 0.3 μm to 150 μm.
The reason for this will be explained below.

A crystal grain size of 0.3- is said to be the critical grain size for single-domain particles, and when the grain size becomes smaller than 0.3-, the disconnection curve changes to the permanent magnet of (3) in the conventional method. The result is the same, and the reef properties become worse.

Furthermore, if the crystal grain size exceeds 150 μm, the coercive force obtained even after hot working will be lower than 4KOe of a ferrite magnet, making it impractical, so the grain size should be reduced to 0.3 μm−15 μm.
01am range.

Furthermore, as shown in FIG. 4, which will be described later, the less the nonmagnetic R-rich phase is, the higher the 4πIs (solid line) is. Since 4πIs decreases as the R-rich phase increases, it is preferably 10% or less in consideration of practicality. However, 0
%, the coercive force will be lost, so it was set at more than 0% and less than 10% (weight).

Next, examples of the present invention will be described.

[Example] [Example 1] A process diagram of the manufacturing method according to the present invention is shown in FIG.

In this example, hot pressing was mainly performed at 1000°C as hot working to orient the magnetic alloy. Regarding hot pressing, the speed was adjusted to minimize the strain rate.

Furthermore, in the high temperature region, the axis of easy magnetization of the crystal was oriented parallel to the direction in which the alloy was pushed.

First, according to the manufacturing process shown in FIG. 1, using an induction heating furnace in an argon atmosphere, Pr Fe B17 78
．． 5 5 Cut, an alloy of composition 5 was melted and then cast.

At this time, rare earth, iron, and copper raw materials with a purity of 999% were used, and boron was ferroboron.

Next, this cast ingot was placed in an argon atmosphere for 100 min.
Hot pressing was carried out at 0° C. with a working degree of 80% as shown in FIG. The press pressure at this time is 0.2 to 0.8
ton/cj, and the strain rate is 10-3 to 10-'/s
It was ec.

After that, it was annealed at 1000° C. for 24 hours, cut and polished, and its magnetic properties were measured.

The magnetic properties and other property test values of this magnet were used as a comparative example, and the sintered permanent magnet (Nd
t5PeyyB 8 ) and (3) permanent magnet (Nd13
Table 1 shows the values in PeB).

82.6 4.4 All magnetic properties are B- at a maximum applied magnetic field of 25 kOe.
H) Measured using a racer.

As shown in Table 1, it is clear that the magnet of the present invention is not inferior in magnetic performance but superior in magnetization compared to the conventional permanent magnets (1) and (3).

It has also been shown that copper-added cast magnets are effective in increasing coercive force and are also effective in improving orientation.

The permanent magnet of the present invention differs from the conventional sintered permanent magnet (1) in O1C content and porosity, and is different from the conventional sintered permanent magnet (1).
) The grain size of the crystal grains is different from that of permanent magnets, and the magnetization is excellent.

Part 1 table Next, the structural mechanism of the magnet of the present invention will be described.

FIG. 2 is a detailed explanatory diagram of the present invention.

In Fig. 2, 11 is Pr2Fe14B phase particle, 12
is an α-Fe phase, 13 is an R-rich phase, and 14 is an R-rich liquid phase.

In the present invention, the permanent magnet of the present invention is manufactured by following the process shown in FIG.

Figure 2 (a) shows “17Fe76.5 B5 cul,
This figure shows the state of the main phase when the raw material alloy No. 5 is melted and cast to form a cast ingot.
A small amount of a-Pe phase 12 is embedded in the r2Fe14B phase particles 11.

The space between the P'2Fe14B phase particles 11 is filled with a nonmagnetic R-rich phase 13.

FIG. 2(b) shows the state in the hot press. At a temperature of 800 to 1050°C, the R-rich phase 13 melts into an R-rich liquid phase 14, and this liquid phase 14 is a hot press. It is removed and pushed outward by pressure applied from outside, such as a press.

In addition, the α-Pe phase 12 diffuses and disappears, and Pr2F
The e14B phase particles 11 are refined during hot pressing, and the principal axis of the crystal is oriented in a certain direction.

Fig. 2(c) shows the state of the magnet, where the R-rich phase 13 that seeps out to the outside is cut off, and the magnet is formed by the central part where the fine Pr2Fe14B phase particles 11 are oriented. use.

Between the Pr2Fe14B phase particles 11, the R-rich phase 1
3, iron and copper, but the amount is much smaller than that of the cast ingot, and the magnetic phase Pr2Pe14B
It is clear that Sairazi 11 is much more concentrated than the initial raw material composition.

Figure 3 shows the content of R-rich phase in the magnet, 411s and I
A relationship diagram with Hc is shown. Also, in Figure 4, P r I 7
4πI- of a magnet with the composition Pe B Cu
The curves in two directions, parallel and perpendicular to the press, are shown when H is pressed.

Figure 3 shows that the less the nonmagnetic R-rich phase is, the more 4πIs
(solid line) indicates an increase.

As the amount of R-rich phase increases, 4π1s decreases, so it can be seen that 10% or less is desirable in consideration of practicality.

Figure 4 shows a typical hot pressed Pr-Fe-B-Cu
Two types of magnet demagnetization curves are shown: easy magnetization direction and difficult magnetization direction.

From FIG. 4, the easy magnetization direction is parallel to the pressing direction. From the separation curve in the direction of easy magnetization, this magnet is nu
It is considered to have a creation type coercive force mechanism.

It can be seen that although the anisotropy direction is the same as that of the conventional permanent magnet (3), the coercive force mechanism is different.

[Example 2] Similarly to Example 1, according to the manufacturing process shown in FIG. 1, using an induction heating furnace in an argon atmosphere, P r 1
79B4 was melted and then cast.

At this time, rare earth and iron raw materials with a purity of 99.9% were used as in Example 1, and ferroboron was used as boron.

Next, this cast ingot was placed in an argon atmosphere for 100 min.
Hot pressing was carried out at 0° C. with a working degree of 80% as shown in FIG. The press pressure at this time is 0.2 to 0.8 t.
on/c-, and the strain rate is 1O-3 to 10-'/se
It was c.

After cutting and polishing, the magnetic properties were measured and 1000
After a heat treatment of 24 hours of annealing at .degree. C., the magnetic properties were measured again.

Table 2 shows the magnetic properties before and after annealing, and Table 3 shows the various characteristic values after annealing.

Further, FIG. 5 shows the demagnetization curve (1) of the cast ingot and the demagnetization curve (2) of the magnet after annealing.

As shown in Table 2 and Table 3, the raw material composition is Prt7Fe79B 4
The magnet composition is 14.8 80.3 4.9 with concentrated Pr Fe B and magnetic phase. The magnetic properties showed good results, and it is clear that the magnetic properties are further improved by annealing, especially as shown in Table 2 and FIG.

Furthermore, under the same manufacturing conditions, the PrQ of the cast ingot was
Alternatively, when the amount of B was changed, the characteristic values of the finished magnet showed changes as shown in FIGS. 6 and 7.

FIGS. 6 and 7 show the composition dependence of hot-pressed magnets, and the measurement directions of the magnetic properties are all parallel to the pressing direction. It is also seen that (B)l)Ilax (MGOe) increases significantly, indicating that it is anisotropic.

[Example 3] An alloy having the composition Pr1□Nd5Pe7°B 5,5 Cut, 5 was melted and cast in the same manner as in Examples 1 and 2 to produce a cast ingot.

Next, this cast ingot was heated to 100% in an argon atmosphere.
It was heated to 0°C, and the strain rate was to-3 to 10-'/sec.
Hot pressing was carried out as shown in FIG. 2 at a processing degree of 80%.

After this, after annealing at 1000°C for 24 hours,
Cutting, polishing, composition '9.5'4 Fe80.1B6.1'0
．． A magnet of No. 3 was obtained, and the magnetic properties of this magnet were measured.

The magnetic properties and other characteristic values of this magnet are shown in Table 4.

As shown in Table 4, it is clear that even if the composition is changed as described above, the magnetic properties are excellent.

Table 4 shows the measurements, and Table 6 shows the composition of the magnet.Table 7 shows the various properties of the magnet.

Table 5 Alloy Composition [Example 4] Alloys having the compositions shown in Table 5 were melted and cast in the same manner as Examples 1 to 3. The same raw materials were also used.

Next, these cast ingots were hot pressed in an argon atmosphere as shown in Figure 2, annealed, cut and polished. Example 5] Similarly to Examples 1 to 4, using the same raw materials, Pr
An alloy having the composition NdFeBCu was melted and cast.

Next, this cast ingot was processed at 900 to 1000[deg.] C. by the following hot working methods as shown in Table 8: (1) hot pressing, (2) rolling, and (2) extrusion.

Note that FIGS. 8 and 9 are explanatory views of hot rolling and extrusion. In the figure, 5 is a roll.

6 is a hydraulic press, and 7 is a die.

In addition, regarding the hot pressing and hot rolling processing of ■ and ■, the stamp 3
．． The speed of roll 5 was adjusted. In both methods, the axis of easy magnetization of the crystal was oriented so as to be parallel to the direction in which the alloy was pushed as shown by the arrow in the high temperature region.

Next, it was annealed at 1000° C. for 24 hours, cut and polished, and its magnetic properties were measured.

Table 9 shows the composition of this magnet, and Table 10 shows the magnetic property values.

Hot press as shown in Tables 8 to 10.

It is clear that the characteristic values are improved in both rolling and extrusion processing methods.

Table 8 Table 9 Composition of magnet Table 10 Various properties of magnet [Example 5] Magnet of the present invention manufactured in Example 1 and conventional magnet (sintering method)
were processed into the same composition (Nd15Fe7□B5) and the same shape, and placed in a constant temperature/humidity chamber at 40° C. and 95% to examine changes in weight. The results are shown in FIG.

As shown in Figure 10, the magnet of the present invention is different from the conventional magnet (sintering method).
It is clear that the weight change is small and the oxygen concentration in the magnet is low compared to the above. This is a major difference from conventional magnets.

From the above examples, R is Pr, Nd, Dy, Ce, La
, Y, and Tb, and M is Pe, Co, Cu, Ag, old, Au,
A permanent magnet whose basic raw material is at least one transition metal element selected from Zr, where X is at least one Group IIIb element selected from B, Ga, and AI, has a high coercive force. It is made anisotropic by heat treatment such as hot pressing, and the maximum (BH) max is 43.6.
It is clear that even MGOe is reached.

[Effects of the Invention] Like a savior, the method for manufacturing a permanent magnet of the present invention has the following effects.

(1) The C-axis orientation rate can be increased, and the residual magnetic flux density B
By making the crystal grains finer, coercive force iHc and maximum energy product (BH) can be significantly improved.
was able to significantly increase.

max (2) The manufacturing process is simple, so the cost is low.

(3) Since the 02 concentration in the magnet is low, it has little activity against oxygen and can improve weather resistance.

(4) Good machinability has the effect of reducing costs.

(5) Compared to conventional sintering methods, processing man-hours and production equipment investment can be significantly reduced.

(6) Compared to the conventional method of producing magnets using melt spinning, it is possible to produce magnets with high performance and at low cost.

[Brief explanation of the drawing]

Figure 1 is a manufacturing process diagram of the R-Fe-B magnet of the present invention, Figure 2 is an explanatory diagram showing the action of the present invention, and Figure 3 is a diagram showing the R-Fe-B magnet of the present invention.
A diagram of the relationship between rich phase content and 4πIs and IHe. Figure 4 is an explanatory diagram of the two-way curves parallel and perpendicular to the press when 4πIH of a magnet is hot-pressed. Figure 5 is a demagnetization curve of a cast ingot. 6 and 7 are explanatory diagrams showing demagnetization curves of magnets after annealing and PrQ or B, respectively.
Figure 8 is an explanatory diagram of rolling processing, Figure 9 is an explanatory diagram of extrusion processing, and Figure 10 is a diagram of the relationship between the magnet characteristic values when Q is varied, and Fig. 10 is a diagram of the relationship between the magnet of the present invention and the conventional sintered magnet. It is a weight change diagram. RriCha @ consumption (W tolo) In the figure, 11: Pr2Pe14B phase particles, 12
: α-Fe phase, 13: R-rich phase, and 14: R-rich liquid phase.

Claims (7)

[Claims] (1) R (where R is at least one rare earth element including Y), M (at least one transition metal element), and X (at least one group IIIb element)
The basic raw material component is R-, which is a non-magnetic material, is melted and cast, and then the cast ingot is hot-processed at a temperature of 500°C or higher to produce R-, which is a non-magnetic material, from the basic component.
Concentrate the magnetic phase by excluding the rich liquid phase,
A method for producing a permanent magnet, characterized by imparting magnetic anisotropy through mechanical orientation. (2) R is at least one rare earth element selected from Pr, Nd, Dy, Ce, La, Y, and Tb; M
is at least one transition metal element selected from Fe, Co, Cu, Ag, Au, Ni, and Zr, and X is B
, Ga, and Al.
2. The method for producing a permanent magnet according to claim 1, wherein the permanent magnet is a group IIIb element. (3) Use 12 to 25% R, 65 to 85% M, and 3 to 10% By hot working at a temperature of ℃ or higher and excluding the non-magnetic R-rich liquid phase from the basic components, R with an atomic percentage of 10-18% and M with an atomic percentage of 72-87% can be obtained.
, a method for producing a permanent magnet, comprising concentrating a magnetic phase consisting of 3 to 10% of X and imparting magnetic anisotropy through mechanical orientation. (4) Claim 3, wherein the crystal grain size is 0.3 μm to 150 μm and the ratio of R-rich phase is 10% or less (excluding 0%).
A method of manufacturing the described permanent magnet. (5) 12-25% Pr in atomic percentage, 65-85%
Fe and 3 to 10% B are the basic ingredients of the raw material, and the alloy as the basic ingredients is melted and cast, and then the cast ingot is hot worked at a temperature of 500°C or higher to produce non-magnetic material from the basic ingredients. By excluding the liquid phase of the R-rich phase, atomic percentages of 10-18% Pr, 72-87%
The magnetic phase consisting of Fe and 3 to 10% B is concentrated, the crystal grain size is 0.3 μm to 150 μm, the ratio of the R-rich phase is 10% or less (not including 0%), and mechanically oriented. A method for producing a permanent magnet, characterized by imparting magnetic anisotropy. (6) The method for manufacturing a permanent magnet according to claim 5, wherein the cast ingot is heat-treated after hot working. (7) 1 selected from hot pressing, hot rolling and extrusion
6. The method of manufacturing a permanent magnet according to claim 5, further comprising hot working seeds.