JPH045738B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a novel rare earth stone material, which is based on FeBR and contains an additive element M1, and in particular does not necessarily require rare rare earth metals such as Sm, and is mainly made of Nd and Pr, which are rich in resources and have few uses. The present invention relates to a method for producing high-performance permanent magnet materials whose main components are light rare earth elements and Fe. 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. Furthermore, there is a need for magnetic materials with high coercive force in many practical applications where extremely large reverse magnetic fields are applied, such as magnetic couplings for motor generators. Representative permanent magnets currently in use are alnico, hard ferrite, and rare earth cobalt magnets. A recent permanent magnet that satisfies high magnetic properties is a rare earth cobalt magnet.
However, rare earth cobalt magnets are Sm
It is very expensive because it uses a large amount of Co, which is unstable in supply. In order for rare earth magnet materials to be used in large quantities in a wide range of fields, it is necessary to use light rare earth metals, which are found in large amounts in ores as rare earth metals, as the main component, without containing large amounts of expensive cobalt. is necessary. As an attempt to develop such a permanent magnet material, an RFe ₂ compound (where R is at least one kind of rare earth metal) has been proposed. Clark (AE
Clark) is an amorphous material obtained by sputtering.
We found that TbFe ₂ has an energy product of 29.5 MGOe at 4.2°K, and when it is heat-treated at 300-500°C, it exhibits a coercive force of 3.4 kOe and a maximum energy product of 7 MGOe at room temperature. A similar study was conducted on SmFe ₂ , which was reported to exhibit 9.2 MGOe at 77°K. However, all of these are thin films created by sputtering and are not magnets that can be used in general speakers or motors. It has also been reported that ribbons made by ultra-rapid cooling of PrFe-based alloys exhibit a high coercive force of 2.8 kOe. Furthermore, Kuhn et al. found that when an amorphous ribbon obtained by ultra-quenching of (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
5kG). However, in this case, the maximum energy product is low due to poor squareness of the magnetization curve (NCKoon et al.
Appl. Phys. Lett. 39 (10) 1981, pp. 840-842). Also, L.Kabacoff et al. (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 thin films produced by sputtering are not practical permanent magnets (bodies) that can be used as such, and practical permanent magnets cannot be obtained from these ribbons or thin films. That is, it is not possible to obtain a bulk permanent magnet body having arbitrary shapes and dimensions from the FeBR-based ribbons or RFe-based thin films that have been proposed so far. Also reported so far
The magnetization curve of FeBR-based ribbons has poor squareness and is not considered a practical permanent magnet material that can compete with conventionally used magnets. Furthermore, ribbons produced by ultra-quench cooling and thin films produced by sputtering are essentially isotropic, and it has been virtually impossible to obtain practical permanent magnets with magnetic anisotropy from them. The basic object of the present invention is to obtain a new permanent magnet material that eliminates the drawbacks of conventional materials, does not necessarily require the use of rare rare earths such as Sm, and does not contain many components that are problematic in terms of resources such as Co. Furthermore, the present invention has good magnetic properties at room temperature, can be formed into any shape and practical size, has a highly square magnetization curve, and can effectively use light rare earth elements, which are abundant in resources. The present invention aims to provide a manufacturing method for easily obtaining a permanent magnet material. The present inventors previously invented a 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 can be used as an amorphous promoting element in the production of amorphous alloys or as an sintering agent in powder metallurgy. It is not added as a crystallization 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 further conducted intensive research on the production method of crystalline permanent magnet materials based on such FeBR ternary compounds.
M1 (Ti, Zr, Hf, HN, Ni, Ge, Sn, Bi, Sb)
It was discovered that a permanent magnet material with extremely excellent magnetic properties, particularly coercive force and squareness, could be obtained by molding FeCoBRM1 alloy powder with a certain composition range, sintering it, and further heat-treating it. It has been reached. That is, according to the present invention, 8 to 30% in atomic percentage
R (where R is at least one kind of rare earth element including Y), 2 to 28% B, and one or more of the following additive elements M1 at a predetermined % or less (However, except for M10%, 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 two or more If M is included, the total amount of M1 is included.
Among the FeBRM1 compositions, the FeBRM1 composition consists of M1 (within a predetermined percentage of the maximum value of each element in M1), and the remainder substantially consists of Fe (including impurities unavoidable in manufacturing).
A composition in which a portion of Fe is replaced with 50% or less of Co (excluding 0%) in the total composition (FeCOBRM1 composition)
A sintered body that is sintered at 900 to 1200℃,
The above object can be achieved by a method for producing a permanent magnet material, which is characterized by heat treatment at 350° C. to the sintering temperature or lower. By the above 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). predetermined amount
The presence of M1 further enhances the effect of increasing the coercive force by this heat treatment, and the presence of Co achieves a sufficiently high Kurie point for practical use. In addition, this FeCoBRM1-based composition further contains one or more of the elements Similar post-sintering heat treatment effects can be achieved for FeCoBRM1-based compositions. 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. The permanent magnet material thus obtained exhibits particularly excellent magnetic properties when it has magnetic anisotropy in the FeCoBRM1 composition described above. The manufacturing method of the present invention is unique in that it can produce magnetically anisotropic permanent magnet materials, unlike conventional FeBR-based amorphous ribbons, but isotropic materials are also different from conventional isotropic permanent magnet materials. You can get better products. Hereinafter, a case will be mainly explained based on the production of a magnetically anisotropic permanent magnet material. In the method for producing a permanent magnet material of the present invention, FeBR
The temperature characteristics of the magnet material are improved by partially replacing Fe with Co in the system composition, and the coercive force and squareness are improved by adding the additive element M1 and aging treatment. It uses light rare earth elements such as Nd and Pr, which are abundant in resources, to exhibit high magnetic properties. Generally, when Co is added to an Fe alloy, the Curie point Tc may rise or fall depending on the amount added, and it is generally difficult to predict the effect of the addition. In the present invention, as a result of replacing Fe with Co, it was revealed that Tc gradually increases as the amount of Co substitution increases. Also, R of the magnet material composition
A similar trend is confirmed regardless of the type. Even a small amount of Co substitution (for example, 1%) is effective in increasing Tc, and depending on the amount of Co substitution, it is about 310 to about 750.
An alloy with any Tc of °C can be obtained, but the Co amount is 50
% (hereinafter, % indicates the atomic percentage in the alloy) or less, a sufficient effect can be obtained, and Co is set to 50% or less in order to achieve iHc of 1 kOe or more (hereinafter, % indicates the atomic percentage in the alloy). B should be 2% or more to satisfy the coercive force of 1 kOe or more, and the residual magnetic flux density Br of hard ferrite should be approximately
In order to achieve 4kG or more, it must be 28% or less. The rare earth element R is required to be 8% or more in order to obtain a coercive force of 1 kOe or more, and is set to 30% or less because it is easily flammable, difficult to handle and manufacture industrially, and is expensive. As B, pure boron or ferroboron can be used, and a material containing Al, Si, C, etc. as an impurity 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 permanent magnet material of the present invention is
Compared to RCo magnet materials, it is advantageous in terms of resources and cost, and even better magnetic properties can be obtained. The bright rare earth element R in the present invention is a rare earth element containing Y and including light rare earths and heavy rare earths, of which one or more 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 have 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. can be used as a mixture with other R, especially Nd, Pr, etc. 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. In the permanent magnet material produced according to the present invention, the additive element M1 has the effect of increasing the coercive force. Increasing the coercive force increases the stability of the magnet and expands its applications. However, as M1 increases, Br decreases, and therefore the maximum energy product (BH) max decreases. Recently, there have been many applications that require high coercive force Hc even if (BH)max is slightly lower, so alloys containing M1 are very useful, but (BH)max is useful in the range of 4MGOe or higher. be. In order to clarify the effect on Br caused by the addition of each additive element M1, we measured the change in Br by varying the amount added, and calculated the Br value of hard ferrite.
The range is equal to or greater than 4kG. In addition, considering the range equivalent to or higher than the (BH) max of hard ferrite of about 4MGOe, the upper limit of the amount of M1 added 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 is 7.0% or less, Sn 3.5% or less, Bi 5.0% or less, and Sb 2.5% or less. M1 does not contain 0%, and one or more types can be added. When two or more kinds of additive elements are contained, the intermediate value of the characteristics of each additive element is generally indicated, and the content of each element is within the range of the above percentages, and the total amount is not more than the maximum value of the percentages for each element. When the FeCoBRM1 composition is within the above range, the maximum energy product (BH) max is equal to or greater than that of a hard ferrite magnet (~4MGOe).
In addition, light rare earth elements (especially Nd, Pr) account for 50% of the total R.
% or more, and 12 to 24% R, 3 to 27% B, Co 50% or less (excluding Co 0%), and additional elements
M1 is Ti4.0% or less, Zr4.5% or less, Hf4.5% or less,
Mn 6.0% or less, Ni 3.5% or less, Ge 5.5% or less,
Sn2.5% or less, Bi4.0% or less, and Sb1.5% or less, the total amount of M1 is less than the atomic percentage of the maximum value of each element contained in M1, and the remainder is substantially For Fe composition range, (BH)max
is in a preferable range of 7MGOe or more. Furthermore, the most preferable range is light rare earth elements (especially Nd, Pr)
containing 50% or more of the total R, and 12 to 20% of R,
4-24% B, Co50% or less (excluding Co0%),
Additive element M1 is Ti3.5% or less, Zr3.5% or less, Hf3.5
% or less, Mn4.0% or less, Ni2.0% or less, Ge4.0% or less, Sn1.0% or less, Bi3.0% or less, and Sb0.5% or less, and the total amount of M1 is the M1 contained (BH)
The max can be more than 10MGOe, and the highest maximum energy product can reach more than 33MGOe. In addition, the Fe-Co-B-R-M1 alloy of the present invention has a temperature coefficient (α) of residual magnetic flux density (Br) of 5% or more of Co and α≦
0.1%/℃, resulting in good temperature characteristics. Not only does it have better temperature characteristics than Fe-BR-R alloys that do not contain Co, but the addition of Co improves each shape of the demagnetization curve. Therefore, the maximum energy product can be improved. Below 25% Co, other magnetic properties (especially the energy product) are not substantially adversely affected. When Co exceeds 25%, (BH)max
decreases. Further, since Co has more corrosion resistance than Fe, it is possible to impart corrosion resistance to the Fe-BR alloy by adding Co. Permanent magnet materials made of FeCoBRM1-based sintered bodies manufactured by the present invention include Fe, Co, B, R,
It is also possible to contain a small amount of Cu, C, S, P, Ca, Mg, O, Si, etc. in addition to M1, making it possible to improve manufacturability and reduce costs. In particular, Cu3.5% or less, S2.0
% or less, C4.0% or less, and P3.5% or less (however, the total amount is below the maximum value of each element).
Even with the inclusion of these elements, it still has Br (about 4 kG) or higher, which is the same level as hard ferrite, and is useful. Further, it is preferable that Ca and Mg are each 4% or less, and O and S are each 2% or less (however, the total amount is below the maximum value of each element). Note that 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, adsorbed components (moisture, oxygen, etc.) from air during processing are likely to be included, but these can be removed during sintering. However, care should be taken in 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 FeCoBRM1 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 FeCoBRM1 alloy powder with an average particle size of 0.3 to 80 μm. If the average particle size exceeds 80 μm, excellent magnetic properties cannot be obtained. average particle size
If the diameter 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, resulting in poor magnetic properties. 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 most preferably 1.0 to 20 μm. 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 using moisture, 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, when alloy powder is 0.5
A molded body is formed by applying a pressure of ~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, this compact is sintered for 0.5 to 4 hours at a temperature range of 900 to 1200°C in a vacuum of 10 ^-2 Torr or less or in an inert gas or reducing gas atmosphere of 1 to 760 Torr and a purity of 99.9% or more. . If the sintering temperature is lower than 900°C, sufficient sintered density and high residual magnetic flux density cannot be obtained. Moreover, 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. Note that the sintering process is considered to be a heating process in which the density increases as the sintering progresses and reaches a sufficient density. 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 above-mentioned air press method, in order to remove the organic solvent, the temperature increase rate is 30 °C/min or less, or the temperature is increased to 200 °C during the temperature rise. Approximately 1 in the temperature range of ~800℃
It is desirable to remove the solvent by holding it for a period of time or more. After sintering, the cooling rate to room temperature is preferably 30°C/min or more to reduce product variation.
In order to improve the magnetic properties through subsequent heat treatment (aging treatment), a cooling rate of 150°C/min or higher is desirable (however, it is also possible to immediately start the heat treatment process following sintering). The aging treatment is performed 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 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. A purity of 99.99% or higher is desirable. The optimum sintering temperature of the alloy of the present invention varies depending on the composition, and the aging treatment must be performed at a temperature below each sintering temperature of the magnet material of the present invention. for example
71Fe5Co8B14Nd2Ti alloy,
For 52Fe25Co5B17Nd1Mn alloy, the upper limit temperature for aging treatment is 950℃ and 1000℃, respectively. In general, the upper limit aging temperature can be increased as the composition is richer in Fe, less B, or less R. However, if the aging temperature is too high, the crystal grains of the alloy of the present invention will grow excessively, leading to a decrease in magnetic properties, especially the 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 put into practical use. Not. Furthermore, 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 obtained by the present invention, the aging treatment temperature is most preferably 450°C to 800°C. The aging treatment is carried out 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 appear, 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 most desirable aging treatment time is 30 minutes to 8 hours. In addition, in the manufacturing method of the present invention, multi-stage aging treatment of two or more stages is also effective as a method for aging the magnetic alloy. For example, 68Fe-5Co-7B-
For 18Nd-2Ge alloy, the first stage is 800℃~900℃
After the first stage aging treatment for 30 minutes to 8 hours at a temperature range of , excellent magnetic properties with high coercive force and high squareness of demagnetization curve can be obtained. The aging treatment after the second stage is effective in significantly improving the coercive force. In addition, as an alternative method of aging treatment, instead of multi-stage aging treatment, the same magnetic properties can be obtained by cooling the temperature range from 350℃ to 950℃ during aging treatment at a constant cooling rate using a cooling method such as air cooling or water cooling. However, the cooling rate at that time is 0.2℃/min ~ 20℃
It needs to be ℃/sec. Note that the same magnetic characteristics can be obtained even if these aging treatments are performed as is after sintering, or if the temperature is raised again after cooling to room temperature after sintering. 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 they are. For isotropic case, R10~25%, B3~23%,
In a composition consisting of 50% or less Co, a certain % M1, the balance Fe and unavoidable impurities, (BH)
You can get more than max2MGOe. Isotropic magnet materials originally have low magnetic properties that are 1/4 to 1/6 of the magnetic properties of anisotropic magnet materials, but according to the present invention, they are nevertheless extremely isotropic. High useful properties are 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)max2MGOe 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)
Must be in the range of B3-23% to obtain max2MGOe or higher. Preferably, light rare earths (particularly Nd, Pr) are the main components of R (rare earths are 50 at% or more in all R) and 12 to 20
With a composition of % R, 5-18% B, and the balance Fe (BH)
Shows high magnetic properties exceeding max4MGOe. The most preferable range is a composition in which light rare earth elements such as Nd and Pr are the main components of R, and 12 to 16% R, 6 to 18% B with the balance Fe, and (BH)max is 7MGOe or more, and isotropic permanent magnet materials. You can obtain characteristics never seen before. For M1, the same range as in the case of anisotropy is preferable except for the following (Ti: 4.7% or less, Ni: 4.7% or less,
Ge6.0% or less). When any M1 component is isotropic, Br shows a decreasing tendency as the amount added increases, and Br3kG or more (to be equal to or higher than the level of (BH)max2MGOe of isotropic hard ferrite) is within this range. Indicated by Binders and lubricants are generally not used in the case of anisotropic materials because they interfere with orientation during molding, but in the case of isotropic magnet materials, containing binders and lubricants improves press efficiency. It is possible to improve the properties of the molded product and increase the strength of the molded product. Even in the case of isotropy, in addition to R, B, Fe, Co, and M1, C, P, S, Cu, Ca, Mg, O, and Si can be contained within a specified range, and C4.0% or less. , P3.3% or less, S2.5% or less, Cu3.3% or less, Ca4% or less,
It is practically preferable that Mg is 4% or less, O2% or less, and Si2% 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 detailed above, the method for manufacturing the permanent magnet material of the present invention has excellent magnetic properties with a novel FeCoBRM1 system having high coercive force and high energy product, and also uses light rare earth elements such as Nd and Pr as R. This makes it possible to easily produce a permanent magnet material that is excellent in terms of resources and cost, and has high industrial applicability. In particular, by substituting a part of Fe with Co, it is possible to obtain a material having a more practical Curie temperature, and by incorporating a predetermined element M1 and subjecting it to a predetermined aging treatment, This is a crystalline FeCoBRM1-based permanent magnet material that has further improved the coercive force and the squareness of the demagnetization curve. The aspects and effects of the present invention will be further explained based on Examples. However, the present invention is not limited to the examples and described aspects. Tables 1 to 4 show the characteristics of permanent magnet materials having various FeCoBRM1 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. As Co, electrolytic Co with a purity of 99.9% was used. M1 includes 99% purity Ti, Bi, Mn, Sb, Ni, Sn,
Ferrozirconium containing 77.5% Zr as Ge, 95% Hf, and 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 pulverized using a ball mill to obtain 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 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 57Fe・15Co・9B・17Nd・2Ti
An alloy powder with an average particle size of 4 μm is heated in a 15 kOe magnetic field.
After pressure molding at a pressure of 1.0Ton/cm ² , it was sintered at 1120°C for 2 hours in 150 Torr Ar with a purity of 99.99%, and after sintering, it was cooled to room temperature at a cooling rate of 500°C/min.
Furthermore, aging treatment was performed at 700℃ for 20 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.
Comparative example of magnet characteristics results and temperature coefficient α (%/℃) of residual magnetic flux density (Br) of this alloy magnet (after sintering)
They are shown in Table 1.

[Table] Example 2 Atomic percentage composition 55Fe−15Co−10B−16Nd・
2Pr−2Hf, 15kOe of alloy powder with average particle size of 3μm
After pressure molding in a magnetic field at a pressure of 1.0Ton/ ^cm2 ,
Sintering was performed at 1160°C for 4 hours in 400 Torr Ar with a purity of 99.999%, and after sintering, the material was cooled to room temperature at a cooling rate of 450°C/min. Further, aging treatment was performed in a vacuum of 3×10 ⁻⁵ Torr at each temperature shown in Table 2 for 4 hours to obtain a magnet material according to the manufacturing method of the present invention. The magnet characteristic results and the temperature coefficient α (%/°C) of the residual magnetic flux density (Br) are shown in Table 2 together with comparative examples (after sintering, etc.).

【table】

[Table] Example 3 Fe-Co-B-R-M1 alloy powder having an average particle size of 2 to 10 μm and the atomic percentage composition shown in Table 3 was
After pressure molding at a pressure of 1.5Ton/ ^cm2 in a 10kOe magnetic field, 1060℃ in 200Torr Ar with 99.999% purity,
Sintering was carried out for 2 hours, and after sintering, it was rapidly cooled to room temperature at a cooling rate of 650°C/min. Furthermore, aging treatment was performed at 650° C. for 4 hours in Ar at 600 Torr to obtain a magnet material according to the manufacturing method of the present invention. The magnetic properties and the temperature coefficient α (%/°C) of Br are shown in Table 3 along with a comparative example that does not contain Co.

[Table] Example 4 Fe-Co-B-R-M1 alloy powder having the following atomic percentage composition and having an average particle size of 2 to 10 μm was prepared in a non-magnetic field.
After pressure molding at a pressure of 1.5Ton/cm ² , it was sintered at 1040°C for 1 hour in 150Torr Ar with 99.9% purity, and after sintering, it was rapidly cooled to room temperature at a cooling rate of 450°C/min. Furthermore, aging treatment was performed at 650℃ in 650Torr Ar.
The process was carried out for 4 hours to obtain an isotropic magnet material according to the manufacturing method of the present invention. 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)

[Claims] 1. 8 to 30% R (wherein R is at least one rare earth element including Y), 2 to 28% in atomic percentage
B, one or more of the additive elements M1 in a specified percentage or less (excluding M1 0%, 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%) Below, Ge is 7.0% or less, Sn 3.5% or less, Bi 5.0% or less, and Sb 2.5% or less, and if two or more types of M1 are included, the total amount of M1 is included.
FeBRM1 consisting of a specified percentage of the maximum value of each element in M1), and the remainder substantially consisting of Fe.
Part of the Fe in the system composition is replaced with 50% or less Co (excluding 0%) of the total composition.
1. A method for producing a permanent magnet material, which comprises heat-treating a sintered body having a FeCoBRM1 composition and sintered at 900 to 1200°C at 350°C to below the sintering temperature. 2 The sintered body has the FeCoBRM1 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 8 to 30% R in atomic percentage (however, R is at least one rare earth element including Y), 2 to 28%
B, one or more of the additive elements M1 in a specified percentage or less (excluding M1 0%, 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%) Below, Ge is 7.0% or less, Sn 3.5% or less, Bi 5.0% or less, and Sb 2.5% or less, and if two or more types of M1 are included, the total amount of M1 is included.
The maximum value of each element in M1 is below a predetermined percentage), one or more of the elements X below a predetermined percentage (element
% or less, C4.0% or less, and P3.5% or more, and when X is two or more types, the total amount of A part of Fe in the FeBRM1 system composition consisting of 50% or less of Co (excluding 0%) in the total composition
It has a FeCoBRM1-based composition consisting of substitution with 900~
A method for producing a permanent magnet material, which comprises heat-treating a sintered body obtained by sintering at 1200°C at a temperature of 350°C to the sintering temperature.