JPH044385B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a permanent magnet material based on FeBR system. Conventionally, alnico, ferrite, etc. have been the main materials for permanent magnets, but with the development of electronics in recent years, the demand for smaller and lighter magnets has increased. As a permanent magnet material that satisfies such requirements, rare earth (R) cobalt magnet materials having high residual magnetic flux density and high coercive force have been developed and put into practical use. In the present invention, R represents a rare earth metal. However, the rare earth cobalt magnet material is Sm
The product price is very high because it contains large amounts of expensive rare earths such as heavy rare earths and expensive cobalt.
This is becoming a major obstacle to replacing alnico and ferrite. In order for rare earth magnet materials to be inexpensive and used in large quantities in a wide range of fields, Nd, which does not contain expensive cobalt and is quantitatively abundant among rare earth elements, is required.
It is necessary to have a light rare earth element such as Pr as a main component, and various attempts have been made to obtain such a permanent magnet material. For example, AEC Clark fabricated TbFe ₂ amorphous by sputtering and obtained 4.2〓
has an energy product of 29.5MGOe at 300-500℃
It was found that when heat treated with A similar study was conducted on SmFe ₂ , which was reported to exhibit 9.2 MGOe at 77〓. In addition, Kuhn (NCKoon) etc. is 0.9 (Fe, B)
It was discovered that when a -0.05Tb-0.05La ribbon was prepared by an ultra-quenching method and then annealed at around 875〓, the Hc exceeded 9kOe. However, in this case, the squareness of the magnetization curve and of course the orientation are poor,
(BH)max is low (NCKoon et al., App1.Phys.
Lett.39(10), 1981, pp. 840-842, IEEE
Transaction on Magnetics, vol.MAG−18, No.
6, 1982, pp. 1448-1450). In addition, JJCroat and L. Kabacoff et al. fabricated ribbons with PrFe and NdFe compositions using an ultra-quenching method and cooled them at room temperature.
reported a value close to 8 kOe (L. Kabacoff et al., J.
App1.Phys.53(3)1981, pp. 2255-2257, JJCroat
IEEE Vol.18No.6 1442-1447). Bulk permanent magnets with arbitrary shapes and dimensions cannot be obtained from these FeBR-based ultra-quenched ribbons or RFe-based sputtered thin films, and it is quite difficult to use them as practical permanent magnet materials. The magnetization curves of FeBR ribbons reported so far have poor squareness, and cannot be considered as practical permanent magnet materials that can compete with conventional magnet materials. Further, both the sputtered thin film and the ultra-quenched ribbon are essentially isotropic, and it is virtually impossible to obtain a practical permanent magnet material with magnetic anisotropy from them. As described above, all the methods conventionally attempted to obtain permanent magnet materials of rare earth iron alloys have been unsuitable for obtaining practical permanent magnet materials. The present invention aims to overcome the difficulties of such conventional methods, and as mentioned above, in a permanent magnet material using Fe and R, light rare earths can be mainly used as R, and it is different from conventional hard ferrite. The basic objective is to provide an optimal manufacturing method for obtaining a new permanent magnet material that has comparable or better magnetic properties and does not require the use of Co, which is a rare resource. Furthermore, in a preferred embodiment of the present invention, the present invention provides an optimum method for obtaining a practical permanent magnet material that imparts an even better coercive force to the FeBR ternary permanent magnet material previously developed and applied for by the present inventor. Another purpose is to provide a manufacturing method. That is, according to the production method of the present invention, 8 to 30% R (wherein R is at least one kind of rare earth element including Y), 2 to 28
% of B, one or more types of additive elements M of a predetermined percentage (herein, the additive elements M of a predetermined percentage are Ti 4.5% or less, Ni 8.0% or less, Bi 5.0% or less, V 9.5% or less, Nb 12.5% or less , Ta 10.5% or less, Cr 8.5% or less, Mo 9.5% or less, W 9.5% or less, Mn 8.0% or less, Al 9.5% or less, Sb 2.5% or less, Ge 7.0% or less, Sn 3.5% or less, Zr 5.5% or less , and Hf 5.5% or less; when there are two or more types of M, the total amount of M is less than the atomic percentage of the maximum value of each of the M elements contained), and the remainder is Fe and impurities unavoidable in manufacturing. It has a composition (hereinafter referred to as FeBRM composition) of 0.3~
Forming an alloy powder with an average particle size of 80μm,
A FeBRM permanent magnet material is produced by sintering at 900 to 1200°C. Regarding alloy compositions below, unless otherwise specified, % represents atomic percentage. The FeBRM permanent magnet material obtained by the production method of the present invention includes at least a magnetically anisotropic permanent magnet material. 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 accelerating 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 actual content of this FeBR-based permanent magnet material. It revealed that. In order to achieve the above object, the inventors of the present invention have conducted further intensive research into FeBR permanent magnet materials based on such FeBR ternary compounds, and have found that FeBR permanent magnet materials containing a predetermined element M and having a predetermined FeBRM composition. When an alloy powder composition with a certain particle size is used and processed powder metallurgically under certain conditions, it not only provides magnetic properties equivalent to or better than conventional alnico, ferrite, and rare earth magnet materials. As a result of detailed research, we discovered that it is possible to manufacture materials with high mass production efficiency, including materials that can be molded into bulk bodies of arbitrary shapes and practical dimensions, and that exhibit even higher coercive force than FeBR systems. It has been reached. The following explanation will be based on the case of producing a magnetically anisotropic permanent magnet material. That is, the permanent magnet material obtained by the production method of the present invention is an industrially useful permanent magnet material that has magnetic properties equivalent to or better than hard ferrite in the above FeBRM composition range according to the present invention. In order to satisfy the coercive force iHc1kOe or more, B should be 2% or more, and the residual magnetic flux density Br of hard ferrite should be
B should be 28% or less in order to achieve 4kG or more. R is required to be 8% or more in order to satisfy a coercive force of 1 kOe or more, and is set to 30% or less because it is easily flammable and difficult to handle and manufacture industrially (and is expensive). Light rare earths (particularly Nd, Pr) are the main components of R (i.e. 50 atomic % or more of the total R), and 12 to 24% R,
The composition of 3 to 27% B and the balance (Fe+M) is a preferable range in order to achieve a maximum energy product (BH) of max7MGOe or more. Most preferably, the main component of R is a light rare earth (particularly Nd, Pr), with 12 to 20% of R, 4 to 24% of B,
The composition of the remainder (Fe + M) enables the maximum energy product (BH) max10MGOe or more, (BH)
The max reaches a maximum of 33MGOe or more. Recently, permanent magnet materials have been exposed to increasingly harsh environments (for example, strong demagnetizing fields due to thinner magnets, strong reverse magnetic fields applied by coils and other magnets, and high temperatures due to higher speeds and higher loads of equipment). environment), and in many applications, even higher coercive force is required to stabilize properties. In the present invention, the FeBRM permanent magnet alloy powder composition contains one or more of the above specific additive elements M, thereby making it possible to provide an even higher iHc than the FeBR ternary permanent magnet material. (See Figure 4). However, it has also become clear that the addition of these additive elements M causes a gradual decrease in the residual magnetization Br in each embodiment. Therefore, the content of the additive element M is such that at least the residual magnetization Br is
The target is those that have a remanent magnetization Br that is equivalent to or higher than that of conventional hard ferrite, and that exhibit a high coercive force. Next, in order to clarify the effect of each addition of the additive element M, we conducted an experiment by changing the amount of addition of Br.
The results are shown in FIGS. 1 to 3. Other additive elements M (Ti, V,
Nb, Ta, Cr, Mo, W, Al, Sb, Ge, Sn, Zr,
As shown in FIGS. 1 to 3, the upper limit of the amount of Hf) added is determined to be equal to or higher than approximately 4 kG of Br of hard ferrite. Furthermore, preferred ranges can be clearly read from FIGS. 1 to 3 by dividing Br into steps of 6.5, 8, 10 kG, etc., respectively. When large amounts of Mn and Ni are added, iHc decreases, but since Ni is a ferromagnetic element, Br does not decrease much (see Figure 2). Therefore, the upper limit of Ni is iHc
From this point of view, it is set at 8%, and from the same point of view, it is preferably 4.5% or less. Mn addition has a greater effect on Br reduction than Ni, but not as sharply. Therefore, the upper limit of Mn is set at 8% from the viewpoint of iHc, and from the same viewpoint, 3.5% or less is preferable. Regarding Bi, its vapor pressure is extremely high and Bi5%
It is virtually impossible to manufacture alloys exceeding 5%. In the case of an alloy containing two or more types of additive elements, in order to satisfy the condition of Br4kG or more, the maximum value (%) of the upper limit of the amount of each element added above must be applied.
It is necessary that the following is true. In the present invention, R of the alloy powder composition for permanent magnets
Light rare earths, which are abundant in resources, can be used as materials, and Sm is not necessarily required, or Sm
The raw materials are cheap because there is no need to use
Extremely useful. The rare earth element R used in the permanent magnet of the present invention is a rare earth element that includes Y and includes light rare earths and heavy rare earths, and one or more of them is used. That is, this R is 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 desirable. Also, it is usually sufficient to have one type of R, but
In practice, a mixture of two or more types (Mitsushimetal, didymium, etc.) can be used for reasons such as convenience of availability. Note that R does not need to be a pure rare earth element; it may contain impurities that are unavoidable during manufacturing (other rare earth elements, Ca, Mg, Fe, Ti, C, O
etc.) may be used. La, Ce,
Pm, Sm, Eu, Gd, Er, Tm, Yb, Lu, Y can be used as a mixture with other rare earths (Nd, Pr, Tb, Dy, Ho). As B, pure boron or ferroboron can be used, and materials containing Al, Si, C, etc. as impurities can also be used. In the present invention, the presence of impurities that are unavoidable during manufacturing can be tolerated in the permanent magnet material. C, S, P, Cu,
It can also contain Ca, Mg, O, Si, etc. within a predetermined limit, contributing to manufacturing convenience and cost reduction. C may be contained as an organic binder, while S, P, Cu, Ca, Mg, O, Si, etc. may be contained from raw materials or manufacturing processes. C4.0
% or less, P3.5% or less, S2.5% or less, Cu3.5% or less,
It is practically preferable that each of Ca and Mg be 4% or less, and Si be 5% or less (however, the total of these is less than the maximum value of each component). Note that in the state of alloy powder, adsorbed components (moisture, oxygen, etc.) from the 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. The manufacturing method of the present invention makes it possible to exhibit high characteristics of the FeBRM permanent magnet material, and the manufacturing method will be explained in more detail below. In general, rare earth metals are chemically very active and easily combine with oxygen in the air and easily react with oxygen to create rare earth oxides.
It is necessary to perform each process such as molding and sintering in a reducing atmosphere or a non-oxidizing atmosphere. First, an alloy powder having a predetermined alloy composition is prepared. As an example, after weighing and blending raw materials to a predetermined composition within the FeBRM composition range described above, melting is performed using a high frequency induction furnace or the like to form an ingot, which is then pulverized. The coercive force (iHc) is 1 KOe or more when the powder average particle size is in the range of 0.3 to 80 μm. If the average particle size is smaller than 0.3 μm, oxidation will proceed rapidly and it will be difficult to obtain the desired alloy, which is not preferable in the present invention for stable production of high-performance products of the specified permanent magnet material. Moreover, when the powder particle size exceeds 80 μm, the coercive force iHc becomes
It is less than 1kOe, which is not preferable in terms of maintaining the performance of the magnet material. Among the powders having a particle size within the above range, two or more powders having different compositions within the composition range of the present invention may be mixed and used in order to adjust the composition or promote densification during sintering. That is, R
FeBR (or
FeBRM) mixture of different composition ratios, or
A powder composition such as a mixture of FeBR (or FeBRM) alloy powder and FeBRM alloy component elements or an alloy consisting of two or more thereof is possible. Although the pulverization may be carried out in the usual way, it is preferable to perform it wetly, using alcoholic solvents such as hexane, trichloroethane, trichlorethylene,
Toluene, fluorine-based solvents, paraffin-based solvents, etc. can be used. Within the above FeBRM composition range, e.g.
After weighing to have a composition of 15 atomic % Nd, 8 atomic % B, and 1 atomic % M, balance Fe, melting was performed to obtain an ingot. When crushing this ingot, the powder particle size is
The grinding conditions were adjusted so that the particle diameter was in the range of 0.3 to 137 μm. Here, the powder particle size refers to the average particle size measured using a subsieve sizer manufactured by Fischer.
For powders with a particle size of 40 μm or more, a JIS standard sieve or microsieve was used. Here, the obtained powder was placed in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 2Ton/ ^cm2 ,
Figure 5 shows the influence of the powder particle size after pulverization on the coercive force (iHc) of the sintered body by performing sintering at temperatures of 1080°C and 1100°C for 1 hour in an Ar200Torr atmosphere. The obtained alloy powder having a predetermined particle size is then molded. The pressure during molding is preferably in the range of 0.5 to 8 Ton/cm ² . If the pressure is less than 0.5Ton/cm ² , the molded product will not have sufficient strength and will be extremely difficult to handle in practical use as a permanent magnet material. Moreover, if it exceeds 8Ton/cm ² , the strength of the molded product will increase significantly, making it easier to handle it, but
This is not preferable since it poses a problem when performing continuous molding in terms of the strength of the press punch and die.
However, the molding pressure is not limited. Furthermore, when producing magnetically anisotropic magnet materials during pressure molding, it is carried out in a magnetic field, and the magnetic field at that time is approximately 7.
Preferably carried out in a magnetic field of ~13 kOe. In addition,
Use a molding binder (auxiliary agent) if necessary. The obtained compact is sintered at a temperature of 900-1200°C, preferably 1000-1180°C. If the sintering temperature is less than 900°C, sufficient density as a permanent magnet material cannot be obtained, and the required magnetic flux density cannot be obtained. Moreover, if the temperature exceeds 1200°C, the sintered body will be deformed, the orientation will be lost, and the magnetic flux density and squareness will decrease, which is not preferable. The sintering time may be 5 minutes or more, but if it is too long, there will be problems in mass productivity, so the preferred sintering time is 30 minutes to 8 hours. Sintering is performed in a reducing or non-oxidizing atmosphere. When an inert gas atmosphere is used as the sintering atmosphere, it may be a constant pressure or pressurized atmosphere, but it is also possible to perform the sintering in a reduced pressure atmosphere or a reduced pressure inert atmosphere as a method of densifying the sintered body. Another method for increasing the sintering density is to conduct the sintering in an atmosphere of H ₂ gas, which is a reducing gas. Through each of the above steps, a magnetically anisotropic permanent magnet material with high magnetic flux density and excellent magnetic properties can be obtained. By the production method of the present invention, a permanent magnet material is obtained as a sintered body, and the density of the sintered body is approximately 80% of the theoretical density, preferably 95% or more in terms of magnetic properties, and more preferably 96% or more. and reaches a maximum of over 99%. Hereinafter, aspects and effects of the present invention will be explained according to Examples. However, the embodiments and descriptions are as follows:
The present invention is not limited to these. (1) The starting 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. M includes Ti, Mo, Bi, Mn with a purity of 99%,
Sb, Ni, Ta, Ge, 98% W, 99.9% Al,
Sn, 95% Hf, also ferrovanadium containing 81.2% V as V, ferronniobium containing 67.6% Nb as Nb, ferrochrome containing 61.9% Cr as Cr, and ferrochromium containing 75.5% Zr as Zr. Zirconium 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 it to 35mesh, it is further processed by ball mill.
Grinding was carried out to obtain particles of 0.3 to 80 μm. (4) Powder is heated in a magnetic field of 7 to 13 kOe at 0.5 to 8 Ton/cm ²
It was molded at a pressure of (However, when manufacturing an isotropic magnet material, it was molded without applying a magnetic field.) (5) The molded body was sintered at a temperature of 900°C to 1200°C. The atmosphere at that time was a reducing gas, an inert gas, or a vacuum. Sintering time is 15 minutes to 8
I went within the time limit. Example 1 Atomic percentage composition (same below) is 76Fe・8B・
An alloy of 15Nd and 1Ti was crushed into a powder with an average particle size of 3 μm, and a compact was made by applying a pressure of 3Ton/ ^cm2 in a magnetic field of 10kOe, and sintered at each temperature for 2 hours in an Ar atmospheric pressure atmosphere. The sintered density and properties are as shown in the table below.

[Table] Example 2 An alloy with the composition 73Fe, 10B, 15Nd, 2V was ground into powder with an average particle size of 5 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 1.5Ton/cm2 ^and 1×
The sintered density and properties when sintered for 1 hour at each temperature in a vacuum of 10 ^-4 Torr were as shown in the table below.

[Table] Example 3 An alloy with the composition 76Fe, 8B, 15Nd, 1Nb was ground into powder with an average particle size of 2 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 2Ton/ ^cm2.
The sintered density and properties when sintered for 1 hour at each temperature in an Ar200 Torr atmosphere are as shown in the table below.

[Table] Example 4 An alloy with the composition 74Fe, 8B, 17Nd, 1Ta was ground into powder with an average particle size of 3 μm, and was ground in a magnetic field of 10 kOe.
A compact was made under a pressure of 1.5Ton/cm ² and sintered at each temperature for 3 hours in an Ar atmospheric pressure atmosphere.The sintered density and properties were as shown in the table below.

[Table] Example 5 An alloy with a composition of 75.5Fe, 10B, 14Nd, 0.5Cr was ground into powder with an average particle size of 2.8 μm, and a compact was made by applying a pressure of 2T/cm ² in a magnetic field of 10kOe.
The sintered density and properties when sintered for 4 hours at each temperature in a vacuum of 1x10 ^-4 Torr were as shown in the table below.

[Table] Example 6 An alloy with the composition 76Fe, 8B, 15Nd, 1Mo was ground into powder with an average particle size of 3.5 μm, and a compact was made by applying a pressure of 3Ton/cm ² in a magnetic field of 10kOe to 60Torr.
The sintered density and properties when sintered in Ar for 2 hours at each temperature are as shown in the table below.

[Table] Example 7 An alloy with a composition of 75.5Fe, 7B, 17Nd, 0.5W was ground into a powder with an average particle size of 3.6 μm, and a compact was made by applying a pressure of 3Ton/cm ² in a magnetic field of 10kOe to Ar atmospheric pressure. The sintered density and properties when sintered in an atmosphere at each temperature for 1 hour were as shown in the table below.

[Table] Example 8 An alloy with the composition 76Fe, 9B, 14Nd, 1Mn was ground into powder with an average particle size of 4.0 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 1.5Ton/ ^cm2 .
The sintered density and properties when sintered for 2 hours at each temperature in an Ar200 Torr atmosphere are shown in the table below.

[Table] Example 9 An alloy with a composition of 76.5Fe, 7B, 16Nd, 0.5Ni was ground into powder with an average particle size of 4.0 μm, and a compact was made by applying a pressure of 2T/cm ² in a magnetic field of 10kOe.
The sintered density and properties when sintered for 1 hour at each temperature in a vacuum of 1x10 ^-4 Torr are shown in the table below.

[Table] Example 10 An alloy with the composition 76Fe, 8B, 15Nd, 1Al was ground into powder with an average particle size of 2.5 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 1.5Ton/ ^cm2 ,
The sintered density and properties when sintered for 2 hours at each temperature in Ar400 Torr were as shown in the table below.

[Table] Example 11 An alloy with a composition of 74.5Fe, 9B, 16Nd, 0.5Ge was ground into powder with an average particle size of 3.5 μm, and a compact was made by applying a pressure of 7.5Ton/ ^cm2 in a magnetic field of 10kOe.
The sintered density and properties when sintered at each temperature for 2 hours in an atmospheric pressure atmosphere are as shown in the table below.

[Table] Example 12 An alloy with the composition 76Fe, 9B, 14Nd, 1Sn was ground into powder with an average particle size of 4.0 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 2.5Ton/ ^cm2 .
The sintered density and properties when sintered for 1 hour at each temperature in Ar400 Torr were as shown in the table below.

[Table] Example 13 An alloy with the composition 75Fe, 9B, 15Nd, 1Sb was ground into powder with an average particle size of 3.1 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 1.5Ton/ ^cm2 .
The sintered density and properties when sintered for 1.5 hours at each temperature in a vacuum of 1x10 ^-4 Torr are shown in the table below.

[Table] Example 14 An alloy with the composition 75Fe, 7B, 17Nd, 1Bi was ground into powder with an average particle size of 2.1 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 2.5Ton/ ^cm2 .
The sintered density and properties when sintered in Ar1Torr at each temperature for 0.5 hours were as shown in the table below.

[Table] Example 15 An alloy with the composition 76Fe, 8B, 15Pr, and 1Al was ground into powder with an average particle size of 4.0 μm, and was ground in a magnetic field of 10 kOe.
A molded body is made by applying a pressure of 1.5Ton/ ^cm2 .
The sintered density and properties when sintered for 2 hours at each temperature in an Ar200 Torr atmosphere are shown in the table below.

[Table] Example 16 An alloy with a composition of 73Fe, 9B, 15Nd, 2Dy, and 1V was ground into powder with an average particle size of 3.1 μm, and a compact was made by applying a pressure of 2.0Ton/cm ² in a magnetic field of 10kOe.
The sintered density and properties when sintered for 1 hour at each temperature in an Ar100 Torr atmosphere are as shown in the table below.

[Table] Example 17 An alloy with the composition 76Fe, 8B, 15Nd, 1Al was ground into powder with an average particle size of 3.0 μm, and was ground without applying a magnetic field.
A molded body was made under a pressure of 3Ton/cm ² and sintered at each temperature for 1 hour under Ar atmospheric pressure.The sintered density and properties were as shown in the table below.

[Table] Furthermore, Figure 6 shows 76.5Fe, 8B, 15Nd, 0.5Al
(Prepared in the same manner as Anisotropic Example 10 of the present invention) is shown in comparison with that of a known amorphous ribbon. Amorphous ribbon 70.5Fe・
15.5B/7Tb/7La is 660℃ after ultra-quenched ribbon formation.
×15 minutes of heat treatment (Source: JJ
Becker, IEEE Transaction on Magnetics.
Vol.MAG-18No.6 1982, p.1451-1453). As seen in the above examples, FeBRM permanent magnet materials can be produced in bulk form with high performance and any size using the powder metallurgy sintering method of the present invention, and can be produced stably and inexpensively. It can be mass-produced and is industrially very useful. Note that it is not possible to manufacture a practical permanent magnet material having such high properties and an arbitrary shape using conventional manufacturing methods such as sputtering and ultra-quenching.

[Brief explanation of drawings]

1 to 3 are graphs showing the relationship between residual magnetization Br (kG) and additive element M (horizontal axis, x atomic %) in Examples of the present invention, and FIG. FIG. 5 is a graph showing the magnetization-demagnetization characteristic curve together with comparative examples, and FIG. 5 is a graph showing the relationship between the average particle size of the alloy powder (horizontal axis log scale μm) and coercive force iHc (kOe) in yet another example. Figure 6 shows
Bulk FeBRM obtained by the production method of the present invention
FIG. 7 is a graph showing a comparison of the demagnetization characteristic curves of a typical example of a FeBR-based permanent magnet material and a conventional FeBR-based amorphous ribbon, and FIG. 7 is a graph showing the relationship between sintering temperature, magnetic properties, and density.

Claims (1)

[Claims] 1 8 to 30% of R in atomic percentage (wherein R is Y
at least one rare earth element including), 2-
28% B, one or more types of additive elements M in a predetermined percentage (here, the additive elements M in a predetermined percentage are Ti 4.5% or less, Ni 8.0% or less, Bi 5.0% or less, V 9.5% or less, Nb 12.5% Below, Ta 10.5% or less, Cr 8.5% or less, Mo 9.5% or less, W 9.5% or less, Mn 8.0% or less, Al 9.5% or less, Sb 2.5% or less, Ge 7.0% or less, Sn 3.5% or less, Zr 5.5% (hereinafter referred to as Hf5.5% or less; when there are two or more types of M, the total amount of M is less than or equal to the atomic percentage of the one having the maximum value among the respective M elements contained), and the remainder is Fe and unavoidable in manufacturing. An alloy powder having a composition consisting of impurities and an average particle size of 0.3 to 80 μm is formed and sintered at 900 to 1200 °C in a reducing or non-oxidizing atmosphere.
Manufacturing method of FeBRM permanent magnet material.