JPH0422012B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the FeBR system, contains the additive element M, and does not use cobalt, which is expensive and a scarce resource.
This invention relates to a method for producing FeBRM permanent magnet materials. Permanent magnetic materials are one of the extremely important electrical and electronic materials used in a wide range of fields, from various household appliances to peripheral terminal equipment for large computers. In recent years, with the demand for smaller and more efficient electrical equipment, permanent magnet materials are required to have even higher performance. In addition, magnetic materials with high coercive force are required in many practical applications such as motors, generators, and magnetic couplings where extremely large reverse magnetic fields are applied. Representative permanent magnets currently in use are alnico, hard ferrite, and rare earth cobalt magnets. However, as the raw material situation for cobalt has recently become unstable, demand for alnico magnets containing 20 to 30% cobalt has decreased, and cheap hard ferrite, which is mainly composed of iron oxide, has become the mainstream magnet material. It became. On the other hand, rare earth cobalt magnets contain 50 to 65% by weight of cobalt and use Sm, which is not included in rare earth ores, so they are very expensive, but because their magnetic properties are much higher than other magnets, they are mainly used for small It is often used in high value-added magnetic circuits. In order for rare earth magnet materials to be used in a wide range of fields and in large quantities, they must not contain expensive cobalt and be mainly composed of light rare earth metals, which are contained in large amounts in ores. is necessary. An RFe ₂ compound (where R is at least one rare earth metal) was proposed as an attempt to develop such a permanent magnet material. Clark (AE
Clark) is an amorphous material obtained by sputtering.
We found that TbFe ₂ has an energy product of 29.5MGOe at 4.2〓, and when it is heat-treated at 300 to 500℃, it exhibits a coercive force of 3.4KOe and a maximum energy product of 7MGOe at room temperature. A similar study was conducted on SmFe ₂ , which was reported to exhibit 9.2 MGOe at 77〓. However, all of these are thin films made by sputtering and are not magnets that can be used in general speakers or motors. In addition, ribbons made by ultra-quenching PrFe-based alloys
It has been reported that it exhibits a high coercive force of 2.8 kOe.
Furthermore, Kuhn et al. found that when an amorphous ribbon obtained by ultra-quenching (Fe.B) _0.9 Tb _0.05 La _0.05 was annealed at 627°C, the coercive force reached as high as 9 kOe (Br was 5 kG). However, in this case, the maximum energy product is low because the magnetization curve has poor squareness (NCKoon
Appl. Phys. Lett. 39 (10) 1981, pp. 840-842). Also, L.Kabacoff and others (FeB) _1-x
It has been reported that ribbons fabricated by ultra-quenching with a composition of Pr _x (x = 0 to 0.3 atomic ratio) have a coercive force of kOe level at room temperature due to the Fe/Pr two component system. These ultra-quenched ribbons or sputtered thin films are not practical permanent magnets (bodies) that can be used as such, and practical permanent magnet materials cannot be obtained from these ribbons or thin films. In other words, the conventionally proposed Fe/B/R ribbon or
It is not possible to obtain a bulk permanent magnet with arbitrary shape and dimensions from an RFe-based thin film. Furthermore, the magnetization curves of the FeBR-based ribbons reported so far have poor squareness and cannot be considered as practical permanent magnet materials that can compete with conventionally used magnet materials. Furthermore, ribbons produced by ultra-quench cooling and thin films produced by sputtering are essentially isotropic, and it is virtually impossible to obtain a practical permanent magnet material with magnetic anisotropy from them. Therefore, the object of the present invention is to eliminate the drawbacks of the conventional method.
The basic purpose is to obtain a new permanent magnet material that does not contain rare substances such as Co and does not necessarily require the use of rare rare earth elements such as Sm. The object of the present invention is to provide a material that can be molded into a specific size, has a highly square magnetization curve, and can effectively use light rare earth elements, which are abundant in resources, and a method for producing the same. The present inventors previously invented an FeBR-based permanent magnet material that does not necessarily require the use of Sm and Co (Japanese Patent Application No. 145072/1982). This FeBR-based permanent magnet material is
It is based on a new compound different from the conventionally known RCo ₅ and R ₂ Co ₁₇ compounds, and in particular boron (B) is used as an amorphous promoting element in the production of amorphous alloys or in powder metallurgy. It is not added as a sintering promoting element, but is an essential constituent element of the R-Fe-B compound that is magnetically stable and has a high magnetic anisotropy constant, which constitutes the substantial content of this FeBR-based permanent magnet material. (In addition, the above
It was also revealed that magnetically anisotropic sintered permanent magnets can be obtained by forming an appropriate microstructure based on FeBR-based permanent magnet materials). Furthermore, such FeBR-based permanent magnet materials can be manufactured by molding alloy powder (composition) with a predetermined composition and an average particle size of 0.3 to 80 μm, and sintering it at 900 to 1200°C in a non-oxidizing atmosphere. He also invented the invention and filed a separate application (Patent Application 1988-88372). In order to achieve the above object, the present inventors also conducted intensive research on a method for manufacturing a crystalline permanent magnet material based on such FeBR ternary compounds.
Consisting of M1 and M2, M2 is V, Nb, Ta, Mo,
At least one of W, Cr, Al, M1 is Ti, Zr,
At least one of Hf, Mn, Ni, Ge, Sn, Bi, Sb
By molding, sintering, and further heat-treating Fe, B, R, and M-based alloy powders with a certain composition range including This discovery led to the present invention. That is, according to the present invention, 8 to 30% in atomic percentage
R (however, R is at least one rare earth element including yttrium Y), 2 to 28% boron B,
A predetermined percentage of additive elements M (however, M consists of at least one type of M1 and at least one type of M2, of which M2 is V 9.5% or less, Nb 12.5% or less, Ta 10.5% or less, Mo 9.5% or less, W 9.5% or less, Cr 8.5% or less, and Al 9.5% or less, M1 is Ti 4.5% or less, Zr 5.5% or less, Hf 5.5% or less, Mn 8.0% or less, Ni 8.0% or less, Ge 7.0% or less, Sn 3.5 % or less, Bi 5.0% or less, and Sb 2.5% or less, and the total amount of M is less than or equal to the maximum value of the above percentage values of the elements contained in M1 and M2,
The same applies when M1 and M2 each contain two or more elements. ), and the balance is iron (Fe) and impurities (FeBRM composition), and is characterized by heat-treating a sintered body formed by sintering at 900 to 1200°C at a temperature of 350°C or higher and below the sintering temperature. The above object is achieved by a method of manufacturing a permanent magnet material. By heat treatment, a significant increase in coercive force can be obtained for a sintered body of the same composition without deteriorating other magnetic properties. This point is extremely significant when compared with the fact that, for example, an increase in coercive force due to an increase in the rare earth element R results in a decrease in residual magnetization (see Japanese Patent Application No. 145072/1982). It is preferable to obtain such a sintered body by molding an alloy powder (composition) having a predetermined composition and an average particle size of 0.3 to 80 μm, particularly by sintering it in a non-oxidizing atmosphere, as in the previous application. . Sintering is
Perform in a reducing or non-oxidizing atmosphere. This permanent magnet material exhibits particularly excellent magnetic properties when the FeBRM composition is anisotropic. The present invention is unique in that a magnetically anisotropic permanent magnet material can be obtained, unlike conventional FeBR-based amorphous ribbons. You can get better products.
Hereinafter, the case of magnetic anisotropy will be primarily explained. % unless otherwise specified in the present invention
represents the atomic ratio. In the manufacturing method of the Fe/BR/M-based magnet material of the present invention, B is added at 2% in order to satisfy the coercive force of 1 kOe or more.
As above, the residual magnetic flux density Br of hard ferrite is
In order to make it approximately 4kG or more, it is less than 28%, and R needs to be more than 8% to make it have a coercive force of more than 1kOe.
In addition, it is easy to twist, making it difficult to handle and manufacture industrially.
Also, since it is expensive, it is set at 30% or less. Pure boron or ferroboron can be used as B (boron), and impurities such as Al, Si,
A material containing C or the like can be used. As R, a light rare earth element which is abundant in resources can be used, and Sm is not necessarily required or Sm does not need to be the main component, so the raw material is inexpensive and extremely useful. The rare earth element R used in the permanent magnet of the present invention is a rare earth element containing Y and including light rare earths and heavy rare earths, of which one or more types are used. That is, this R includes Nd, Pr, La, Ce,
Tb, Dy, Ho, Er, Eu, Sm, Gd, Pm, Tm,
Yb, Lu and Y are included. As R, a light rare earth element is sufficient, and Nd and Pr are particularly preferred. In addition, it is usually sufficient to use one type of R, but in practice, a mixture of two or more types (Mitsushimetal, dididim, etc.) can be used for reasons such as convenience of availability.
Sm, Y, La, Ce, Gd etc. are other R, especially Nd, Pr
It can be used as a mixture with Note that R does not have to be a pure rare earth element, and it is also possible to use an element containing impurities that are unavoidable in production as long as it is industrially available. As a synthetic powder, an Fe-BRM alloy or a mixture of two or more such alloys can be used.
In addition, base alloys (Fe-B-R, Fe-B-R-
M), as well as alloys of R and constituent elements, such as R-
Fe alloys, alloys of other basic elements Fe, B, and R and additive elements M, etc. can be used. In particular, these alloys can be used supplementarily to adjust the composition. The M component can also be used as a single powder, and the other components can also be supplemented with single powders. In the permanent magnet material obtained by the present invention, the additive element M has the effect of increasing the coercive force (particularly M2 significantly). Increasing the coercive force increases the stability of the magnet and expands its applications. But M
As the amount of addition increases, Br decreases, and therefore the maximum energy product (BH) max decreases. High coercive force even if (BH)max is slightly lower
Since the number of applications requiring Hc has increased recently, alloys containing M are very useful, but (BH)max is useful in the range of 4MGOe or more. In order to clarify the effect of each addition of the additive element M on Br, the amount added was varied.
The change in Br was measured and the Br of hard ferrite was approximately 4kG.
The range is equal to or greater than. The effect of each element of M on Br is disclosed in Japanese Patent Application No. 57-200204 (No.
~Figure 3), and as the amount added increases,
Br decreases almost uniformly except for Bi, Mn, and Ni.
Also, hard ferrite (BH) max about 4MGOe
The upper limit of the amount of M added is as follows.
For M2, V9.5%, Nb12.5%, Ta10.5%, Mo9.5%, W9.5
%, Cr8.5%, Al9.5%, and for M1, Ti4.5%, Zr5.5%, Hf5.5%, Mn8.0%, Ni8.0
%, Ge7.0%, Sn3.5%, Bi5.0%, and Sb2.5%. M1 and M2 do not contain 0%, and one or more types of each of M1 and M2 can be used in addition. M2
If two or more of each of
within the range and the total amount is the above percentage for each element.
be less than or equal to the maximum value of For example, when V, Ta, and W are included, the total amount of M2 is 10.5% or less.
This also applies to M1. and M1
When containing two or more types of M2 and two or more types of M2, the total amount shall be less than the maximum value of the above percentage for each contained element. For example V, Nb, Ti and Zr
When containing M, the total amount of M shall be 12.5% or less. The permanent magnet material obtained by the present invention is as described above.
Maximum energy product (BH) in FeBRM composition
The max is equal to or higher than that of hard ferrite magnets (~4MGOe). Further, in order to make (BH)max 7MGOe or more, preferably the composition is as follows. That is, it contains light rare earth elements (particularly Nd, Pr) in 50% or more of the total R, and contains 11 to 24% of R, 3 to 27% of B, and additional elements.
M2 is V 8.0% or less, Nb 10.5% or less, Ta 9.5% or less, Mo 7.5% or less, W 7.5% or less, Cr 6.5% or less, Al 7.5% or less, or M1 is Ti 4.0% or less, Zr 4.5% or less. , Hf 4.5% or less, Mn 6.0% or less, Ni 3.5% or less, Ge 5.5% or less, Sn 2.5% or less, Bi 4.0% or less, Sb 1.5% or less, among which M1 and
The total amount of M2 is equal to or less than the atomic percentage of the element having the maximum value among the contained elements of M1 and M2, and the remainder is substantially within the composition range of Fe. The most preferable range is light rare earth elements within 50% of the total R.
% or more, and 12 to 20% R, 4 to 24% B, and the additive element M2 is V 6.5% or less, Nb 8.5% or less, Ta 8.5% or less, Mo 5.5% or less, W 5.5% or less, Cr 4.5 % or less, and one or two or more types with Al5.5% or less,
Regarding the additive element M1, Ti 3.5% or less, Zr 3.5% or less, Hf 3.5% or less, Mn 4.0% or less, Ni 2.0% or less, Ge 4.0% or less, Sn 1.0% or less, Bi 3.0% or less, Sb 0.5% One or more of the following, and M1 and
The total amount of M2 is equal to or less than the atomic percentage of the element having the maximum value among the contained elements of M1 and M2, and the remainder is substantially within the composition range of Fe. In this case, (BH)max is sufficiently possible to be more than 10MGOe, and the highest maximum energy product reaches more than 33MGOe. In addition, the amount of M added is determined by the iHc increasing effect, Br
Considering the decreasing trend and the effect on (BH)max,
It is most preferably 0.1 to 3%, and Al is particularly effective as M2. In addition, in the production method of the present invention, alloy powder (composition),
In addition, the obtained permanent magnet materials include Cu, C, S, P,
It is also possible to contain small amounts of Ca, Mg, O, Si, etc., making it possible to improve manufacturability and reduce costs. In particular, Cu3.5% or less, S2.0% or less, C4.0% or less,
P3.5% or less (however, the total amount is below the maximum value of each element) is practically preferable. Even with the inclusion of these elements, it is still comparable to hard ferrite.
Br (approximately 4kG) or higher and is useful. moreover,
For example, Ca and Mg are each less than 4%, O,
As for S, it is preferable that each content is 2% or less (however, the total amount is below the maximum value of the elements concerned).
Cu and P may be mixed in from inexpensive raw materials, C may be mixed in from organic molding aids, etc., and S may be mixed in during the manufacturing process. In addition, in the state of alloy powder, processing steps,
Adsorbed components from the air (moisture, oxygen, etc.) are likely to be included, but these can be removed during sintering.
However, care should be taken regarding processing and storage as necessary. In addition, the present invention is practical in that it can tolerate the presence of impurities that are inevitable in industrial production. The manufacturing method of the present invention will be further explained below regarding the case of manufacturing a magnetically anisotropic permanent magnet material. First, an alloy powder (composition) having the aforementioned Fe/BRM composition is obtained as a starting material. This may be obtained by crushing an alloy ingot obtained by ordinary alloy melting and casting, classification, blending, etc., or it may be obtained by a reduction method from an oxide using a reducing agent such as Ca. ,
It is preferable to use Fe.B.R.M alloy powder with an average particle size of 0.3 to 80 μm. If the average particle size exceeds 80 μm, excellent magnetic properties tend not to be obtained. If the average particle size is less than 0.3 μm, the oxidation of the powder becomes significant during pulverization or the subsequent manufacturing process, and the density after sintering does not increase and the resulting magnetic properties tend to be poor. In the average particle size range of 40 to 80 μm, the coercive force among the magnetic properties is somewhat low. In order to obtain excellent magnetic properties, the average particle size of the alloy powder is
1.0-20μm is most desirable. The pulverization may be carried out by a conventional method, and may be either dry pulverization carried out in an inert gas atmosphere or wet pulverization carried out in an organic solvent. In the case of a wet method, alcohol solvents, hexane, trichloroethane, trichloroethylene, xylene, toluene, fluorine solvents, paraffin solvents, etc. can be used. Next, the alloy powder is shaped. The molding can be carried out in the same manner as the usual powder metallurgy method, preferably pressure molding, and in order to obtain anisotropy, pressing in a magnetic field. For example, alloy powder is placed in a magnetic field of 50 kOe or more.
A molded body is formed by applying a pressure of 0.5 to 3.0Ton/cm ² . This pressure molding in a magnetic field can be performed either by molding the powder as it is or by molding it in an organic solvent such as acetone or toluene. Next, this molded body is sintered at a predetermined temperature (900 to 1200°C) in a reducing or non-oxidizing atmosphere.
For example, the molded body is placed in a vacuum of 10 ^-2 Torr or less, or 1 to 760 Torr (preferably with a purity of 99.9 Torr).
% or more) in an inert gas or reducing gas atmosphere at a temperature range of 900 to 1200°C for 0.5 to 4 hours. If the sintering temperature is lower than 900°C, sufficient sintered density and high residual magnetic flux density cannot be obtained. Also
Above 1200°C, the sintered body is deformed and the orientation of crystal grains is disrupted, resulting in a decrease in residual magnetic flux density and a decrease in the squareness of the demagnetization curve. Further, the sintering time may be at least 5 minutes, but if it is too long, there will be a problem in mass productivity, so in consideration of the reproducibility of the magnetic properties, the sintering time is preferably 0.5 to 4 hours. The sintering atmosphere is a non-oxidizing atmosphere, such as a high vacuum or an inert gas or reducing gas atmosphere, since R, which is a component in this alloy, is extremely susceptible to oxidation at high temperatures. The higher the purity of the sexual gas, the better. When using an inert gas, it is also possible to carry out the sintering in a reduced pressure atmosphere of 1 to less than 760 Torr as a method of obtaining high sintering density. The temperature increase rate during sintering is not particularly specified, but in the case of the wet press method mentioned above, in order to remove the organic solvent, the temperature is increased at a rate of 30 °C/min or less, or the temperature is increased to 200 °C/min or less during the temperature increase. Approximately 1 in a temperature range of 800℃
It is desirable to remove the solvent by holding it for a period of time or longer. After sintering, the cooling rate to room temperature is preferably 20°C/min or more, preferably 30°C/min or more to reduce product variation, and the cooling rate should be set to 20°C/min or more, preferably 30°C/min or more, to reduce product variation. 150℃/min or more is desirable (however, it is also possible to start the heat treatment process immediately after sintering). Preferably, after sintering, the temperature is below 800℃.
Cool at a rate of 100℃/min or more. Thereafter, aging treatment may be performed continuously, or aging treatment may be performed by cooling to room temperature and then reheating. The aging treatment is carried out in a vacuum, inert gas, or reducing gas atmosphere at a temperature range from 350° C. to below the sintering temperature for approximately 5 minutes to 40 hours, and in some cases 70 hours. The aging treatment atmosphere should be a vacuum of 10 ^-3 Torr or less, or an inert gas or reducing gas atmosphere, since R, the main component in the alloy, reacts rapidly with oxygen or moisture at high temperatures. purity of
99.99% or higher is desirable. In the manufacturing method of the present invention, the optimum sintering temperature varies depending on the composition, and the aging treatment must be performed at a temperature below each sintering temperature of the magnet material. for example
67Fe13B18Nd1W1Hf alloy, 80Fe4B14Nd1AlSb
For alloys, the upper limit temperature for aging treatment is 930℃ and 1020℃, respectively.
It is ℃. Generally rich in Fe or low in B,
Alternatively, the lower the R content of the composition, the higher the upper limit aging treatment temperature can be. However, if the aging treatment temperature is too high, the crystal grains of the resulting alloy will grow excessively, leading to a decrease in magnetic properties, especially coercive force, and the optimum aging treatment time will be extremely short, making it difficult to control the manufacturing conditions and making it difficult to use in practical applications. Not. Further, if the temperature is lower than 350°C, the aging treatment time will take an extremely long time, making it impractical, and the squareness of the demagnetization curve will deteriorate, making it impossible to obtain an excellent permanent magnet. In order to practically obtain excellent magnetic properties without causing excessive growth of crystal grains in the permanent magnet material of the present invention, the aging treatment temperature should be set at 450°C.
800℃ is preferable, more preferably 500~700℃
It is ℃. The aging treatment is performed for 5 minutes to 70 hours, but if the aging treatment time is less than 5 minutes, the effect of the aging treatment will hardly be apparent, and the obtained magnet properties will vary widely. On the other hand, if the aging treatment exceeds 70 hours, it is difficult to say that it is practical because it takes too long for industrial purposes. In order to practically obtain excellent magnetic properties with good reproducibility, the aging treatment time is preferably 30 minutes to 8 hours. It is desirable that the aging treatment be performed in a substantially isothermal state. In addition, multi-stage aging treatment of two or more stages is also effective as a method of aging treatment for this magnetic alloy, with the first stage being heated to 800°C.
As mentioned above, the temperature in the second and subsequent stages can be set to 800°C or less. For example, 77Fe−7B−14Nd− sintered at 1040℃
For the 1Mo-1Go alloy, the first stage aging treatment is performed at a temperature range of 800°C to 900°C for 30 minutes to 8 hours, and then the second and subsequent stages are aged at a temperature range of 400°C to 700°C.
By performing the aging treatment at least once for a period of 70 hours, excellent magnetic properties with high residual magnetic flux density, coercive force, and squareness of the demagnetization curve can be obtained. In particular, the second and subsequent aging treatments are effective in significantly improving coercive force. In addition, as another method of aging treatment, instead of multi-stage aging treatment, aging treatment is performed at 400℃ to 800℃.
The temperature range may be cooled at a constant cooling rate using a cooling method such as air cooling or water cooling, but the cooling rate in this case must be from 0.2°C/min to 20°C/min. Note that these aging treatments may be performed as is after sintering, or may be performed by once cooling to room temperature after sintering and then raising the temperature again. Further, the manufacturing method of the present invention can be applied not only to magnetically anisotropic permanent magnet materials but also to isotropic permanent magnet materials. In addition, in the method for producing an isotropic permanent magnet material, the alloy powder is molded without being placed in a magnetic field, and other steps can be used as is. For isotropic case, R10~25%, B3~23%,
In a composition consisting of a predetermined percentage of M, the remainder Fe, and unavoidable impurities, (BH)max2MGOe or more can be obtained. Isotropic magnets originally have low magnetic properties that are 1/4 to 1/6 of the magnetic properties of anisotropic magnets, but according to the present invention, they have high properties that are extremely useful as isotropic magnets. is obtained. Even in the case of isotropy, as the amount of R increases, iHc
increases, but Br decreases after reaching its maximum value.
Thus, the amount of R that satisfies (BH)max 2MGOe or more is 10% or more and 25% or less. Also, as the amount of B increases, iHc increases, but Br
decreases after reaching its maximum value. Thus (BH) max
Must be in the range of B3-23% to get more than 2MGOe. Preferably, light rare earths (particularly Nd, Pr) are the main components of R (total R medium light rare earths are 50 atomic % or more).
With a composition of 20% R, 5 to 18% B, and the balance Fe, it exhibits high magnetic properties exceeding (BH)max4MGOe.
The most preferable range is light rare earth elements such as Nd and Pr as the main component of R, and a composition of 12 to 16% R, 6 to 18% B, and the balance Fe, where (BH)max is 7MGOe or more and is an isotropic permanent magnet material. This allows you to obtain unprecedented high characteristics. M is preferably within the same range as in the case of anisotropy except for the following. (W8.8% or less, Ni4.7% or less,
Ge6.0% or less). If both M components are isotropic,
As the amount added increases, Br shows a decreasing tendency,
Br3kG or more (isotropic hard ferrite (BH)
max 2MGOe level or higher)
is shown within this range. Binders and lubricants are generally not used in the case of anisotropic magnets because they interfere with orientation during molding, but in the case of isotropic magnets, binders and lubricants are included to improve press efficiency. It is possible to improve the strength of the molded product, etc. Even in the case of isotropy, in addition to R, B, Fe, and M, C, P, S, Cu, Ca, Mg, O, and Si can be contained within a predetermined range, and C4.0% or less, P3 .3 or less,
S2.5% or less, Cu3.3% or less, Ca4% or less, Mg4%
Hereinafter, it is practically preferable that O2% or less and Si5% or less (however, the total of these is the maximum value or less of each component). Note that the presence of other impurities that are unavoidable in industrial production can be tolerated, as in the case of anisotropic materials. As described in detail above, the method for producing a permanent magnet material of the present invention provides a novel Fe-B-R-M-based permanent magnet material having excellent magnetic properties including high coercive force and high energy product. Also, as R, Nd,
By using light rare earth elements such as Pr, it is a permanent magnet that is excellent in terms of resources and cost, and has high industrial applicability. especially,
By further incorporating predetermined elements M (M1 and M2) into the FeBR system and subjecting it to a predetermined aging treatment, the coercive force and demagnetization curve of the crystalline FeBRM permanent magnet material can be further improved. This achieves improved squareness. The aspects and effects of the present invention will be further explained below with reference to Examples. However, the present invention is not limited to the examples and described aspects. Tables 1 to 4 show the characteristics of permanent magnet bodies having various Fe/B/R/M compositions produced by the following steps. (1) The starting raw materials are electrolytic iron with a purity of 99.9% (weight%, the same applies to raw material purity below) as Fe, and feroboron alloy (19.38% B, 5.32% Al, 0.74% B) as B.
%Si, 0.03%C, balance Fe), purity 99% as R
The above (impurities are mainly other rare earth metals) are used. M2 is 99% pure Ta, 98% W, 99.9
% Al, fluorovanadium containing 81.2% V as V, ferronniobium containing 67.6% Nb as Nb, and ferrochrome containing 61.9% Cr as Cr. As M1, 99% purity Ti, Bi, Mn, Sb,
75.5% as Ni, Sn, Ge, 95% Hf and Zr
Ferrozirconium containing Zr was used. (2) Magnet raw materials were melted using high-frequency induction. At that time, an aluminum crucible was used as the crucible, and an ingot was made by casting into a water-cooled copper mold. (3) Crush the ingot obtained by melting.
After making the powder into 35 mesh, it was further ground using a ball mill to obtain particles with a predetermined average particle size. (4) The powder was molded under a predetermined pressure in a magnetic field (however, when manufacturing an isotropic magnet material, molding was performed without applying a magnetic field). (5) The compact was sintered at a predetermined temperature and in a predetermined atmosphere within the range of 900 to 1200°C, and then subjected to a predetermined heat treatment. Example 1 Atomic percentage composition 72Fe−9B−16Nd−2Ta−
1Mn, average particle size 2μm alloy powder in 15kOe magnetic field
After pressure molding at a pressure of 1.0Ton/cm ² , it was sintered at 1100°C for 2 hours in 650Torr Ar with a purity of 99.999%, and after sintering, it was cooled to room temperature at a cooling rate of 600°C/min.
Furthermore, aging treatment was performed at 700℃ for 30 minutes, 120 minutes, and 240 minutes.
This was carried out for 3000 minutes to obtain a magnet material according to the manufacturing method of the present invention.
Table 1 shows the magnet characteristics results.

[Table] Example 2 Atomic percentage composition 70Fe−10B−13Nd−4Pr−2W
-1Ni, an alloy powder with an average particle size of 4 μm was press-molded in a 12 kOe magnetic field at a pressure of 1.0Ton/ ^cm2 , and then
It was sintered at 1070°C for 2 hours in 200 Torr Ar with a purity of 99.999%, and after sintering, it was cooled to room temperature at a cooling rate of 450°C/min. Further, aging treatment was performed in a vacuum of 4×10 ⁻⁵ Torr at each temperature shown in Table 2 for 2 hours to obtain a permanent magnet material. The magnetic property results are shown in Table 2 together with comparative examples (after sintering, etc.).

【table】

[Table] Example 3 Fe-BRM alloy powder having an average particle size of 1 to 8 μm and the atomic percentage composition shown in Table 3 was press-molded in a 15 kOe magnetic field at a pressure of 1.0Ton/cm ² to give 99.999.
% purity at 1085°C for 2 hours in 200 Torr Ar, and after sintering, it was rapidly cooled to room temperature at a cooling rate of 550°C/min. Furthermore, aging treatment was performed at 600° C. for 2 hours in Ar at 550 Torr to obtain a permanent magnet material.
The magnet property results are shown in Table 3 together with a comparative example (magnet properties after sintering).

[Table] Example 4 Fe-BRM alloy powder having the following atomic percentage composition and having an average particle size of 2 to 12 μm was prepared in a non-magnetic field.
After pressure molding at a pressure of 1.7Ton/cm ² , it was sintered at 1100°C for 2 hours in 200 Torr Ar with a purity of 99.999%, and after sintering, it was rapidly cooled to room temperature at a cooling rate of 650°C/min. Furthermore, aging treatment was performed in 250 Torr Ar.
The process was carried out at 650°C for 8 hours to obtain a permanent magnet material. The results of the magnetic properties are shown in Table 4 together with the sample after sintering without aging treatment (comparative example).

【table】

Claims (1)

[Scope of Claims] 1 8 to 30% R in atomic percentage (wherein R is at least one of the rare earth elements including yttrium Y)
species), 2 to 28% boron B, specified % M (however, M
consists of at least one type of M1 and at least one type of M2, of which M2 is V 9.5% or less, Nb 12.5% or less, Ta 10.5% or less, Mo 9.5% or less, W 9.5% or less, Cr 8.5% or less, and Al 9.5% or less, M1 is Ti 4.5% or less, Zr 5.5% or less, Hf 5.5% or less, Mn 8.0% or less, Ni 8.0% or less, Ge 7.0% or less, Sn 3.5% or less, Bi 5.0% or less, and Sb is 2.5% or less, and the total amount of M is not more than the maximum value of the above percentage values of the elements contained in M1 and M2,
The same applies when M1 and M2 each contain two or more elements. ), and the balance consists of iron Fe and impurities
A method for producing a permanent magnet material, which comprises heat-treating a sintered body having a FeBRM composition and sintered at 900 to 1200°C at a temperature of 350°C to below the sintering temperature. 2. The sintered body has the FeBRM composition,
A method for producing a permanent magnet material according to claim 1, which is obtained by molding and sintering an alloy powder composition having an average particle size of 0.3 to 80 μm. 3. The method for producing a permanent magnet material according to claim 1 or 2, wherein the sintered body is obtained by molding and sintering the alloy powder composition having the FeBRM composition in a magnetic field. 4 The sintered body has an R content of 10 to 25% in atomic percentage.
(R is at least one rare earth element including yttrium Y), 3 to 23% boron B, the predetermined percentage M, and the balance is iron Fe and impurities.
2. The method for producing a permanent magnet material according to claim 1, which is obtained by molding and sintering an alloy powder having a FeBRM composition and an average particle size of 0.3 to 80 μm in a non-magnetic field.