JPH06112019A - Nitride magnetic material - Google Patents

Abstract

PURPOSE:To obtain rare earth-iron-nitrogen magnetic material having high magnetic characteristics and excellent oxidation-resistant property by a method wherein a metal element is commonly contained in the rare earth-iron-nitrogen material having the structure of rhombohedral or hexagonal crystal. CONSTITUTION:This nitride magnetic material is indicated by the formula Ralpha(Fe(1-r)Mgamma)(100-alpha-beta)Nbeta, R indicates at least a kind of rare-earth elements containing Y, M indicates at least a kind selected from V, Nb, Ta, Mo, W, Ti, Zr and Hf, alpha and beta are atomic percentage as in 3<=alpha20 and 3<=beta<=30, and gammaindicates atomic ratio as in 0.001<=gamma<=0.5. The phase having R, Fe, M and N contains the crystal structure of rhombohedral crystal or hexagonal crystal. As a result, a rare earth-iron-nitrogen magnetic material, having excellent oxidation-resisting property and high magnetic characteristics, can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rare earth-iron-nitrogen based magnetic material having high magnetic properties and excellent oxidation resistance, and more particularly to a magnetic material most suitable for applications such as small motors and actuators.

[0002]

2. Description of the Related Art Magnetic materials are used in a wide range of fields such as home electric appliances, audio products, automobile parts and peripheral terminals of computers, and their importance as electronic materials is increasing year by year. In particular, recently, there has been a demand for miniaturization and high efficiency of various electric / electronic devices, so that a magnetic material with higher performance is required.

In response to the demands of this era, Sm-Co type, N
The demand for rare earth magnetic materials such as d-Fe-B system is rapidly increasing. However, the Sm-Co type has a problem that the supply of the raw material is unstable and the raw material cost is high, and the Nd-Fe-B type has poor heat resistance and corrosion resistance. On the other hand, as a new rare earth magnetic material, a rare earth-iron-nitrogen magnetic material has been invented. (For example, JP-A-2-57663) This material has high magnetization, anisotropic magnetic field, and high Curie point.
It is expected as a magnetic material that supplements the drawbacks of the d-Fe-B system.

However, when a rare earth-iron-nitrogen-based material is finely pulverized and used, the surface is oxidized and the coercive force is lowered, and the high magnetic properties originally possessed by this material cannot be sufficiently exhibited. . As a countermeasure against this, a method of improving the magnetic material by adding a metal component M to the rare earth-iron-nitrogen based material can be considered. Materials having this rare earth-iron-M-nitrogen composition are disclosed in JP-A-60-144906 and JP-A-6-146906.
0-144909.

JP-A-60-144906, 144909
The material disclosed in (1) is a material containing a large amount of iron nitride, α-iron, rare earth nitride, and nitrides of M and M in manufacturing, and therefore, magnetic properties such as coercive force are significantly deteriorated,
These materials do not become high performance magnet materials. A rare earth-iron-M-nitrogen-based material having a rhombohedral or hexahedral crystal structure with high magnetic properties and excellent in oxidation resistance is not currently known, and its appearance is strongly desired.

[0006]

DISCLOSURE OF THE INVENTION According to the present invention, a rare earth-iron-nitrogen-based material having a rhombohedral or hexagonal crystal structure is allowed to coexist with a metal element M, and high magnetic properties and excellent oxidation resistance are obtained. The present invention provides a magnetic material having a rare earth-iron-M-nitrogen composition and a method for producing the same.

[0007]

[Means for Solving the Problems] In order to obtain a rare earth-iron-nitrogen based magnetic material having high magnetic properties and oxidation resistance, as a result of extensive studies on a system in which various elements (M) are added to a mother alloy, The present invention has been accomplished by finding a rare earth (R) -iron (Fe) -M-nitrogen (N) based magnetic material having a composition and a crystal structure with high magnetic properties and excellent oxidation resistance.

That is, the present invention provides (1) the general formula Rα (Fe
_{(1- γ) Mγ) (100-} α - β) is a magnetic material represented by N.beta, at least one kind of rare earth element R, including the Y, M is, V, Nb, Ta, Mo , W, Ti , Zr, H
At least one of the elements of f, α and β are atomic percentages 3 ≦ α ≦ 20 3 ≦ β ≦ 30 γ are atomic ratios 0.001 ≦ γ ≦ 0.5, and R, Fe and M And a magnetic material in which the phase containing N contains a rhombohedral or hexagonal crystal structure, and (2) 0.01 of Fe which is a component of the magnetic material according to claim 1 above. A magnetic material having a composition in which ˜50 atomic% is replaced with Co, and (3) the general formula Rα _{/ (100-} β ₎ (Fe _(1- γ ₎ Mγ)
_The alloy represented by _(100- α _- β _{) / (100-} β ₎ is heat-treated at a temperature of 200 to 650 ° C. in an atmosphere containing at least one of nitrogen gas and ammonia gas. The method for producing a magnetic material according to claim 1 or 2.

The present invention will be described in detail below. As rare earth (R), Y, La, Ce, Pr, Nd, P
m, Sm, Eu, Gd, Tb, Dy, Ho, Er, T
It suffices to include at least one of m, Yb and Lu. Therefore, a mixture of two or more kinds of rare earth elements such as misch metal and didymium may be used, but preferable rare earth elements are Y, Ce, Pr, Nd, Sm, Gd, Dy, E
r. More preferably, Y, Ce, Pr, Nd,
It is Sm.

Further, this R may have a purity which can be obtained by industrial production, and impurities which are unavoidable in production, such as O, H,
C, Al, Si, F, Na, Mg, Ca, Li and the like may be present. Iron (Fe) is the basic composition of the present magnetic material that is responsible for ferromagnetism, and up to 50 atomic% thereof may be replaced with Co. V, Nb, Ta, Mo, W, T which are essential components for exerting the effect of the present invention
For each element (M) of i, Zr, and Hf, 1 out of M
0.1 or more with respect to the total amount of Fe and M
Coexist in the range of 50 atom%.

The composition of the R-Fe-MN magnetic material in the present invention is in the range of 3 to 20 atomic% of rare earth, 50 to 94 atomic% of iron and M components together, and 3 to 30 atomic% of N. Need to be in. When the R component is less than 3 atom%,
The soft magnetic phase containing a large amount of iron component separates, and the coercive force of the nitride decreases, so that a practical permanent magnet cannot be obtained. Also, the R component is 2
If it exceeds 0 atom%, the residual magnetic flux density is lowered, which is not preferable. The composition of the rare earth is preferably 5 to 15 atom%, more preferably 7 to 12 atom%.

The amount of M coexisting in iron must be in the range of 0.001 to 0.5 in terms of atomic ratio with respect to the total of iron and M components. If it exceeds 0.5, the saturation magnetization is lowered, which is not preferable, and if it is less than 0.001, there is almost no effect of adding M on the oxidation resistance. Furthermore, Ta, Nb, Ti, Z
Since the metal radii of r and Hf are greatly different from those of Fe, if the coexisting amount of M exceeds 0.2 in atomic ratio, it is difficult to maintain a rhombohedral crystal or a hexagonal crystal, which is not preferable.

Considering the balance of magnetic properties such as magnetization and coercive force, the coexisting amount of M is preferably 0.01 to 0.2 as a γ value. Furthermore, iron is 0.01 in Co
When the substitution is up to 50 atom%, the Curie point and the magnetization are high,
Further, the material has high oxidation resistance. V and N as M components
In addition to b, Ta, Mo, W, Ti, Zr, and Hf, L
i, Na, K, Mg, Ca, Sr, Ba, Cr, Mn,
Ni, Pd, Cu, Ag, Zn, B, Al, Ga, I
1 of n, C, Si, Ge, Sn, Pb, Bi elements
One kind or two or more kinds (M ′ component) may be added, but the contents of these are V, Nb, Ta, Mo, W, Ti and Z.
Do not exceed the total amount of r and Hf, and also V, Nb, T
The total amount of a, Mo, W, Ti, Zr, and Hf must be within the range of the γ value.

The crystal structure of the main phase of the R-Fe-MN magnetic material must contain at least one of rhombohedral and hexagonal crystals in a volume fraction of 50% or more. The main phase is a phase containing R, Fe, M, and N and having a rhombohedral or hexagonal crystal structure, and a phase having other composition and crystal structure is called a subphase. For example, the subphase may include a highly magnetic nitride phase having a tetragonal structure such as RFe _12-X M _X N _y phase, but in order to fully exert the effect of oxidation resistance of the present invention, The volume fraction should not exceed the volume fraction of the magnetic material of the present invention.
When the volume fraction exceeds 75% by volume, it is a very preferable material for practical use.

The main phase of the R-Fe-M-N-based material obtained in the present invention has a crystal structure having substantially the same symmetry as the main raw material phase of the R-Fe-M alloy used as the raw material, and nitrogen is It enters into the interstitial lattice or is introduced by substituting it with the M component or the like, and the crystal lattice is expanded in many cases. Main raw material phases are R and F
It means a phase containing e and M and having a rhombohedral or hexagonal crystal structure, and a phase having a composition and a crystal structure other than that and not containing N is referred to as an auxiliary material phase.

With the expansion of the crystal lattice, one or more of the items of oxidation resistance and magnetic properties are improved, and the magnetic material is suitable for practical use. The magnetic properties referred to here are the saturation magnetization (4πIs) of the material, the residual magnetic flux density (Br), the magnetic anisotropy magnetic field (Ha), the magnetic anisotropy energy (Ea), the magnetic anisotropy ratio, and the Curie point ( Tc), intrinsic coercive force (iHc),
Squareness ratio (Br / 4πIs), maximum energy product [(B
H) max], thermal demagnetization rate (α), and coercive force temperature change rate (β). However, the magnetic anisotropy ratio is the ratio (a / a) between the magnetization (a) in the difficult magnetization direction and the magnetization (b) in the easy magnetization direction when an external magnetic field of 15 kOe is applied.
b), and the smaller the magnetic anisotropy ratio, the higher the magnetic anisotropy energy is evaluated.

For example, when Sm _10.5 (Fe _0.9 V _0.1 ) _89.5 having a rhombohedral structure is selected as the rare earth-iron-M alloy, by introducing nitrogen, the crystal magnetic anisotropy becomes in-plane anisotropy. Changes to uniaxial anisotropy suitable as a hard magnetic material, and magnetic properties such as magnetic anisotropy energy and oxidation resistance are improved. The amount of nitrogen (N) introduced is 3 to
It must be 30 atom%. If it exceeds 30 atomic%, the magnetization is low, and its practicality as a magnet material is small.
If it is less than 3 atomic%, the performance of the raw material alloy cannot be improved so much, which is not preferable. The amount of nitrogen is more preferably 5 to 25 atom%, particularly preferably 10 to 17 atom%.

Further, depending on the R-Fe-M composition ratio of the target R-Fe-M-N magnetic material and the amount ratio of the sub-phase,
The optimum amount of nitrogen is different, for example, Nd having a rhombohedral structure.
_{When 10.5} (Fe _0.9 Nb _0.1 ) _89.5 is selected as the raw material alloy, the optimum nitrogen content is around 13 to 14 atom%. The optimum nitrogen amount at this time is the nitrogen amount for which at least one item of the oxidation resistance and magnetic properties of the material is optimal although it varies depending on the purpose, and the optimal magnetic property is the magnetic anisotropy ratio,
The absolute value of the temperature change rate of the demagnetization rate and the coercive force is minimum, and the others are maximum.

The R—Fe—M—N magnetic material obtained by the present invention contains 0.01 to 10 atomic% of hydrogen (H) and 0.01 to 15 atomic% of oxygen (O). It is preferable. A more preferable amount of hydrogen and oxygen is 0.1 to
It is 10 atomic% and 0.1-10 atomic%. Therefore, the particularly preferable composition of the R-Fe-M-N-based material of the present invention is
General formula R α (Fe _(1- γ ₎ M γ) _(100- α _- β _- δ _- ε
₎ When expressed in NβHδOε, α, β, δ, ε is in atomic%, 2.4 ≦ α ≦ 20 2.4 ≦ β ≦ 30 0.1 ≦ δ ≦ 10 0.1 ≦ ε ≦ 10 γ atomic The ratio is in the range of 0.001 ≦ γ ≦ 0.5.

The coexistence effect of the M component with respect to the R-Fe-N magnetic material is mainly improvement of oxidation resistance. In particular,
Deterioration of the R—Fe—N-based magnetic material due to oxidation causes a problem of a decrease in coercive force as compared with a decrease in magnetization. The composition of the present invention is characterized by excellent stability of coercive force against oxidation. The source of the effect is due to the coexistence of the M component in the main phase of the R-Fe-N magnetic material that is responsible for ferromagnetism. However, the main phase itself is not easily oxidized and prevents deterioration of the magnetization. The M component is contained in the soft magnetic component mainly composed of iron, and the precipitation state is affected, which also contributes to preventing the decrease in the coercive force of the nitride magnetic material.

In addition to the object of the present invention, depending on the preparation method and conditions of the mother alloy, the R-rich nitride phase near the grain boundaries or the RFe ₃ phase and the α-Fe phase or its nitride phase may be used. In the material having the R-Fe-N composition as described above, a large amount of the M component is distributed to the sub-phase exhibiting soft magnetism to make it into a non-magnetic phase, which also has the effect of improving the squareness ratio and coercive force of the nitride. .

The production method of the present invention will be illustrated below. (1) Preparation of master alloy In the magnetic material of the present invention, R-Fe- serving as a nitriding raw material
The main raw material phase of the M alloy has a structure in which the M component replaces the Fe site in the R-Fe alloy crystal, or the auxiliary raw material phase has a composition and structure different from the binary system of R-Fe by the addition of M.
The effect of the present invention is exhibited. Therefore, it is desirable to add M at the stage of adjusting the mother alloy.

The R-Fe-M alloy can be produced by R,
High-frequency melting method in which Fe and M metals are melted by high frequency and cast in a mold, arc melting method in which metal components are charged in a boat such as copper and melted by arc discharge, high-frequency molten metal is rotated on a copper roll Quenching method for obtaining a ribbon-shaped alloy, a gas atomization method for obtaining an alloy powder by spraying a high-frequency molten metal with a gas, Fe and / or M powder or Fe-M alloy powder, R and / or M powder R / D method of reacting an oxide powder and a reducing agent at a high temperature to reduce R or R and M while diffusing R or R and M into Fe and / or Fe-M alloy powder. A mechanical alloying method in which a metal component alone and / or an alloy is reacted while being finely pulverized by a ball mill or the like, and the alloy obtained by any one of the above methods is heated in a hydrogen atmosphere, and once converted into a hydride of R and / or M. Decomposed into Fe and or M or Fe-M alloy, both the may be used in the HDDR method alloying are recombined while removing hydrogen as low at a high temperature after this.

When the high frequency melting method or the arc melting method is used, a soft magnetic component mainly composed of Fe is likely to precipitate from the molten state when the alloy is solidified, and particularly the coercive force is lowered even after the nitriding step. Therefore, for the purpose of eliminating the soft magnetic component or improving the crystallinity, the temperature is 800 ° C. or higher in an inert gas such as argon or helium or in a vacuum.
It is effective to anneal in the temperature range of 1300 ° C.
The alloy produced by this method has a large crystal grain size, good crystallinity, and high residual magnetic flux density, as compared with the case of using the ultra-quenching method.

When the ultraquenching method is used, fine crystal grains are obtained, and submicron particles can be prepared depending on the conditions. However, when the cooling rate is high, the alloy becomes amorphous and the magnetic properties such as magnetization are deteriorated even after nitriding. Also in this case, annealing after alloy preparation is effective.
The alloy obtained by the gas atomization method often takes a spherical form, and fine powder to coarse powder can be prepared. Also in this case, depending on the conditions, it is necessary to perform annealing to improve the crystallinity. R / D in addition to this method
The alloy prepared by the method, the mechanical alloying method, and the HDDR method can adjust fine crystal grains and have a distribution in the composition of the M component, so that the effect of the present invention is more remarkable. It is possible to

By the way, depending on the annealing conditions, the crystal phase of the alloy may differ. For example, depending on the R component,
Depending on whether it is annealed or quenched, it may have a rhombohedral system or a hexagonal system. Therefore, it is necessary to pay sufficient attention to the annealing conditions, and the target crystal phase can be selected by controlling the annealing conditions. (2) Coarse crushing and classification It is also possible to directly nitride the alloy ingot produced by the above method, but if the crystal grain size is larger than 500 μm, the nitriding time will be longer, and it is better to carry out coarse crushing before nitriding. It is efficient.

For coarse crushing, a jaw crusher, a hammer,
It is performed by using a stamp mill, a rotor mill, a pin mill, a coffee mill, or the like. Further, even if a crusher such as a ball mill or a jet mill is used, it is possible to prepare an alloy powder suitable for nitriding depending on the conditions. Also, after coarse crushing,
Adjusting the particle size using a sieve, a vibration type or a sonic type classifier, or a cyclone is also effective for performing more uniform nitriding.

After coarse pulverization and classification, annealing in an inert gas or hydrogen can remove structural defects, which is effective in some cases. In the above, the rare earth-iron alloy powder raw material or ingot raw material preparation method in the production method of the present invention has been illustrated.
The optimum conditions for nitriding shown below differ depending on the microstructure and surface condition. (3) Nitriding / annealing Nitriding is performed by using a gas containing a nitrogen source such as ammonia gas or nitrogen gas obtained in the above (1) or (1) and (2).
In this step, nitrogen is introduced into the crystal structure by bringing it into contact with the Fe-M alloy powder or ingot.

At this time, coexistence of hydrogen in the nitriding atmosphere gas is preferable because the nitriding efficiency is high and the nitriding can be performed while the crystal structure is stable. Also argon, helium,
An inert gas such as neon may coexist.
The nitriding reaction can be controlled by gas composition, heating temperature, heat treatment time, and pressure. Among them, the heating temperature is selected in the range of 200 to 650 ° C., though it depends on the mother alloy composition and the nitriding atmosphere. If the temperature is 200 ° C. or lower, the penetration rate of nitrogen is slow and the reaction takes too long, which is not preferable, and if the temperature is 650 ° C. or higher, the main phase is decomposed and the magnetic properties are deteriorated.

After nitriding, it is preferable to anneal in an inert gas and / or hydrogen gas in order to improve the magnetic properties. Examples of the nitriding / annealing device include horizontal and vertical tubular furnaces, rotary reaction furnaces, and closed reaction furnaces. It is possible to adjust the magnetic material of the present invention in any of the apparatuses, but it is preferable to use a rotary reactor in order to obtain a powder having a uniform nitrogen composition distribution.

The gas used for the reaction is a gas flow system in which a gas flow of 1 atm or more is fed into the reaction furnace while keeping the gas composition constant, an encapsulation system in which the gas is sealed in a container at a pressure of 0.01 to 70 atm. Supply them in combination. As a method for producing the present magnetic material, a step of preparing a master alloy having an R—Fe—M composition by the method exemplified in (1) and (2) and then nitriding it by the method shown in (3) is used. Is most preferable, and according to this method, the M component having a high melting point can be contained in a desired portion of the mother alloy, which is particularly effective in improving the oxidation resistance.

The above is a description of the method for producing the R—Fe—M—N magnetic material of the present invention. Particularly, when the magnetic material of the present invention is applied as a practical hard magnetic material, (4)
Fine pulverization, (5) magnetic field molding, and (6) magnetization may be performed. The example will be briefly described below. (4) Fine pulverization For example, among single-domain particle type R—Fe—M—N magnetic materials, when it is desired to maintain a large crystal grain size even after nitriding treatment and to develop a large coercive force, Fine pulverization is performed when it is desired to keep the polycrystalline particles even after the treatment and to obtain an anisotropic hard magnetic material.

As a method of fine pulverization, a rotary ball mill,
Vibratory ball mills, planetary ball mills, wet mills, jet mills, cutter mills, pin mills, automatic mortars and combinations thereof are used. The fine pulverization method is selected according to the adjustment of the amount of hydrogen or oxygen and the target pulverized particle size.

As a method for controlling the amounts of hydrogen and oxygen within the particularly preferable range of the present invention, for example, when a jet mill is used, the oxygen and water vapor concentrations in the pulverized gas are kept at predetermined concentrations, and an attritor or the like is used. When the wet pulverization is used, methods such as adjusting the amount of oxygen and water dissolved in the solvent can be mentioned. (5) Magnetic field molding For example, when the magnetic powder obtained in (3) or (4) is applied to an anisotropic bonded magnet, it is mixed with a thermosetting resin or a metal binder and then compression molded in a magnetic field. After kneading with a thermoplastic resin, injection molding in a magnetic field,
Magnetic field molding.

The magnetic field shaping is preferably 10 kOe in order to sufficiently orient the R-Fe-MN magnetic material in the magnetic field.
Above, more preferably in a magnetic field of 15 kOe or more. (6) Magnetization The anisotropic bonded magnet material and the sintered magnet material obtained in (5) are usually magnetized in order to improve the magnet performance.

The magnetization is, for example, an electromagnet that generates a static magnetic field,
It is performed by a condenser magnetizer that generates a pulsed magnetic field. The magnetic field strength for sufficiently magnetizing is preferably 15 kOe or more, more preferably 30 kOe or more.

[0037]

EXAMPLES The present invention will be specifically described below with reference to examples. The evaluation method is as follows. (1) Magnetic characteristics An R-Fe-MN magnetic material having an average particle diameter of about 3 μm was used at an external magnetic field of 15 kOe and 12 ton / cm ² at 5 mm × 1.
After shaping into about 0 mm × 2 mm and pulse-magnetizing at room temperature with a magnetic field of 60 kOe, the intrinsic coercive force (iHc / kOe) was measured using a vibrating sample magnetometer (VSM). (2) Nitrogen amount, nitrogen amount and hydrogen amount Si ₃ N ₄ (including a fixed amount of SiO ₂ ) as a standard sample,
The amount of nitrogen and oxygen was quantified by the inert gas melting method. The amount of hydrogen was quantified by an inert gas melting method using high-purity hydrogen gas (99.999%) as a standard gas. (3) Average particle size It was evaluated using a Lee-Nurse specific surface area meter. (4) Oxidation resistance performance A molded product of powder having an average particle diameter of about 3 μm evaluated in (1) is
The sample was placed in a thermostatic chamber at 110 ° C., and the intrinsic coercive force after 200 hours was measured in the same manner as in (1). The higher the retention rate, the higher the oxidation resistance performance. (5) Oxidation test 10 mg of a coarse powder sample adjusted to an average particle size of about 15 μm was placed in a thermobalance, and the weight from 50 ° C. to 250 ° C. was set in a 50 ml / min air stream at a temperature rising rate of 10 ° C./min. The rate of change (% by weight) was measured. The smaller the weight change rate, the less likely it is to be oxidized.

[0038]

Example 1 Sm having a purity of 99.9%, Fe having a purity of 99.9%, and V having a purity of 99.9% were melt-mixed in a high-frequency melting furnace under an argon gas atmosphere, and then the molten metal was a pure iron mold. Pour into the inside and cool, and further in an argon atmosphere,
Sm by annealing at 1050 ° C. for 35 hours
An alloy having a composition of _10.9 (Fe _0.9 V _0.1 ) _89.1 was prepared.

This alloy was crushed by a jaw crusher and then further crushed by a rotor mill in a nitrogen atmosphere, and the particle size was adjusted by a sieve to obtain a powder having an average particle size of about 50 μm. The Sm-Fe-V alloy powder was charged into a horizontal tubular furnace, and the ammonia partial pressure was 0.32a at 450 ° C.
After heat treatment in a mixed air flow of tm and hydrogen gas of 0.68 atm, followed by annealing in an argon air flow, the average particle size was adjusted to about 15 μm. Then, the powder was pulverized by a jet mill to an average particle size of about 3 μm. At this time, as the pulverizing gas, a gas containing nitrogen as a main component and partially mixing oxygen and water vapor was used.

Table 1 shows the composition, oxidation resistance and oxidation test results of the obtained Sm-Fe-VN powder. Also, the intrinsic coercive force of the Sm-Fe-VN system powder compact pulverized to about 3 µm is 5.6 kOe, and the residual magnetic flux density is 8.3 kG.
Met. As a result of analysis by an X-ray diffraction method, the crystal structure of this material was mainly rhombohedral, and no diffraction line corresponding to V alone was observed.

[0041]

Examples 2 to 12 R-was carried out in the same manner as in Example 1 except that the composition of the mother alloy was changed to the composition ratio shown in Table 1.
Fe-MN powder was obtained. The results are shown in Table 1. Note that as a result of X-ray diffraction, the materials except for Example 7 accounted for the majority of substances having rhombohedral crystals, and the materials for Example 7 contained substances having rhombohedral crystals and substances having tetragonal crystals. I found out that

[0042]

[Comparative Example 1] Sm-Fe was prepared in the same manner as in Example 1 except that V was not added and Fe (atomic%) was added.
-N-based powder was obtained. The results are shown in Table 1.

[0043]

Comparative Example 2 Sm obtained in Example 1 having a particle size of about 3 μm
_A magnetic powder having a composition of _9.1 (Fe _0.9 V _0.1 ) _74.4 N _13.7 H _0.5 O _2.3 was magnetically molded under the conditions of ² ton / cm ² and 15 kOe, and then heat-treated at 800 ° C. for 1 hour in an argon atmosphere. . The intrinsic coercive force of the molded body when quenched was 0.04 kOe. The intrinsic coercive force of the powder obtained by pulverizing this compact again to about 3 μm is 0.04 kOe.
Met. As a result of analyzing the crystal structure of this material by X-ray diffraction, diffraction lines mainly corresponding to α-iron and iron nitride were detected.

[0044]

[Table 1]

[0045]

As described above, according to the present invention, it is possible to provide a rare earth-iron-nitrogen based magnetic material having excellent oxidation resistance and high magnetic properties.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display part H01F 1/06

Claims (3)

[Claims] 1. The general formula R α (Fe _(1- γ ₎ M γ) _(100- α
_{- beta)} is a magnetic material represented by N.beta, at least one of the at least one, M is, V, Nb, Ta, Mo , W, Ti, Zr, Hf element selected from rare earth elements R are including Y, α and β are atomic percentages 3 ≦ α ≦ 20 3 ≦ β ≦ 30 γ is an atomic ratio 0.001 ≦ γ ≦ 0.5, and the phase containing R, Fe, M and N is a diamond. A magnetic material containing a tetrahedral or hexagonal crystal structure. 2. A magnetic material having a composition in which 0.01 to 50 atomic% of Fe, which is a component of the magnetic material according to claim 1, is replaced by Co. 3. The general formula Rα _{/ (100-} β ₎ (Fe _(1- γ ₎ M
γ) _(100- α _- β _{) / (100-} β ₎ is characterized in that it is heat-treated in the range of 200 to 650 ° C. in an atmosphere containing at least one of nitrogen gas and ammonia gas. The method for producing a magnetic material according to claim 1 or 2, wherein