DE102018120212A1 - Magnetic connection, manufacturing method and magnetic powder - Google Patents

Abstract

[SOLVING PROBLEM]
A rare earth-iron-based magnetic compound having a ThMn ₁₂ type crystal structure in which the anisotropic magnetic field and the saturation magnetization are further increased to provide a manufacturing method thereof and a magnetic powder.
[MEANS OF SOLVING THE PROBLEM]
A magnetic compound having a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e (in the formula, R is one or more rare earth elements except for Nd, T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is an unavoidable impurity element, etc., A is one or more elements selected from the group consisting of N, C, H and P, 0 <x≤0,3, 0≤y≤0,1, 0≤z≤0,3, 7,7 <a: 9,4, b = 100-acd, 3,1≤c <7 , 7, 0≤d≤1,0, and 1≤e≤18) satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3, and with a ThMn ₁₂ type crystal structure, a manufacturing method thereof and a magnetic powder.

Description

[TECHNICAL FIELD]

The present disclosure relates to a magnetic compound, a manufacturing method thereof, and a magnetic powder. More particularly, the present disclosure relates to a magnetic compound having both an anisotropic magnetic field and a high saturation magnetization, a manufacturing method thereof, and a magnetic powder.

[STATE OF THE ART]

The application of a permanent magnet extends to wide fields including electronics, information communication, medical engineering, the machine tool field, industrial and automobile engines, etc. In addition, a demand for the reduction of carbon dioxide emission is increasing, and therefore, for example, due to the spread of a hybrid car and the Energy savings in the industrial area as well as increasing energy production efficiency, increasingly expected the development of a permanent magnet with better properties.

At present, an Nd-Fe-B magnet dominating the market as a high-power magnet is used as a drive motor magnet for HV / EHV. In response to the current trend of further advancing the size reduction and the stronger output (increase in the residual magnetization of the magnet) of a motor, the development of a new permanent magnet material is proceeding.

As one of developments of a material having a performance exceeding the Nd-Fe-B magnet, a rare earth-iron-based magnetic compound having a ThMn ₁₂ -type crystal structure is being investigated.

For example, Patent Document 1 discloses a magnetic compound having a composition represented by the formula:
(R _(1-x) Zr _{x) a} (Fe _(1-y) CO _{y) b} T _c M _d A _e (where R is one or more rare earth elements, T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au, A is one or more elements selected from the group consisting of N, C, H and P is 0≤x≤0.5, 0≤y≤0.6, 4≤5a≤20, b = 100-acd, 0 <c <7, 0≤d≤1, and 1≤e≤ 18) and having a ThMn ₁₂ type crystal structure.

[RELATED ART]

[Patent Document]

[Patent Document 1] Japanese Unexamined Patent Publication No. 2016-58707

[SUMMARY OF THE INVENTION]

[Problems to be Solved by the Invention]

In the magnetic compound disclosed in Patent Document 1, the reduction in the α-Fe phase content is insufficient, and there is a limit to further increase the anisotropic magnetic field and the saturation magnetization. Accordingly, the inventors of the present invention have found a challenge in meeting the desire to more increase the anisotropic magnetic field and the saturation magnetization in a rare earth-iron-based magnetic compound having a ThMn ₁₂ -type crystal structure.

The present disclosure has been made to attain the foregoing object, and an object thereof is to provide a rare earth-iron-based magnetic compound having a ThMn ₁₂ -type crystal structure in which the anisotropic magnetic field and the saturation magnetization are further increased, a production method for that and a magnetic powder.

[Means to solve the problem]

• <1> Magnetische Verbindung mit einer durch die Formel:
  • (Nd_(1-x-y)R_yZr_x)_a(Fe_(1-z)CO_z)_bT_cM_dA_e dargestellten Zusammensetzung (in der Formel,
    • ist R ein oder mehrere Seltenerdeelemente mit Ausnahme von Nd,
    • ist T eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Ti, V, Mo und W,
    • ist M unvermeidbare Verunreinigungselemente und eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Al, Cr, Cu, Ga, Ag und Au,
    • ist A eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus N, C, H und P,
    • 0<x≤0,3,
    • 0≤y≤0,1,
    • 0≤z≤0,3,
    • 7,7<a:9,4,
    • b= 100-a-c-d,
    • 3,1≤c<7,7,
    • 0:5≤d≤1,0, und
    • 1≤e≤18),
    • erfüllt, in der Formel, die Beziehungen a≥1,6x+7,7 und c≥-14x+7,3 und
    • weist eine ThMn₁₂-Typ Kristallstruktur auf.
• <2> Magnetische Verbindung nach Punkt <1>, wobei in der Formel 3,1≤c≤7,3 ist.
• <3> Magnetische Verbindung nach Punkt <1> oder <2>, wobei in der Formel 7,7<a≤8,7 ist.
• <4> Verfahren für die Herstellung der magnetischen Verbindung nach Punkt <1>, umfassend:
  • Zubereiten eines geschmolzenen Metalls mit einer Zusammensetzung dargestellt durch die Formel (Nd_(1-x-y)R_yZr_x)_a(Fe_(1-z)CO_z)_bT_cM_d (in der Formel,
    • ist R ein oder mehrere Seltenerdeelemente mit Ausnahme von Nd,
    • ist T eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Ti, V, Mo und W,
    • ist M unvermeidbare Verunreinigungselemente und eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Al, Cr, Cu, Ga, Ag und Au,
    • 0<x≤0,3,
    • 0≤y≤0,1,
    • 0≤z≤0,3,
    • 7,7<a:9,4,
    • b= 100-a-c-d,
    • 3,1≤c<7,7,
    • 0≤d≤1,0), und erfüllt, in der Formel, die Beziehungen a≥1,6x+7,7 und c≥-14x+7,3,
    • Abschrecken des geschmolzenen Metalls mit einer Geschwindigkeit von 1×10² bis 1×10⁷ K/sec, um ein Band zu erhalten, und
    • Ermöglichen, dass A (eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus N, C, H und P) in das Band eindringt.
• <5> Verfahren nach Punkt <4>, das außerdem das Pulverisieren des Bandes vor dem Eindringen umfasst, um ein Pulver zu erhalten.
• <6> Verfahren nach Punkt <5>, das außerdem die Wärmebehandlung des Bandes bei 800 bis 1.300°C über 2 bis 120 Stunden umfasst.
• <7> Verfahren nach Punkt <5> oder <6>, das außerdem die Wärmebehandlung des Pulvers bei 800 bis 1.300°C über 2 bis 120 Stunden umfasst.
• <8> Verfahren nach einem der Punkte <4> bis <7>, wobei in der Formel 3,1≤c≤7,3 ist.
• <9> Verfahren nach einem der Punkte <4> bis <8>, wobei in der Formel 7,7<a≤8,7 ist.
• <10> Magnetisches Pulver, umfassend eine Zusammensetzung dargestellt durch die Formel (Nd_(1-x-y)R_yZr_x)_a(Fe_(1-z)CO_z)_bT_cM_dA_e (in der Formel,
  • ist R ein oder mehrere Seltenerdeelemente mit Ausnahme von Nd,
  • ist T eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Ti, V, Mo und W,
  • ist M unvermeidbare Verunreinigungselemente und eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus Al, Cr, Cu, Ga, Ag und Au,
  • ist A eines oder mehrere Elemente ausgewählt aus der Gruppe bestehend aus N, C, H und P,
  • 0<x≤0,3,
  • 0≤y≤0,1,
  • 0≤z≤0,3,
  • 7,7<a:9,4,
  • b= 100-a-c-d,
  • 3,1≤c<7,7,
  • 0:5≤d≤1,0, und
  • 1≤e≤18),
  • erfüllt, in der Formel, die Beziehungen a≥1,6x+7,7 und c≥-14x+7,3 und
  • weist eine ThMn₁₂-Typ Kristallstruktur auf.

The inventors made many intensive studies to obtain the foregoing subject matter, and created the magnetic compound of the present disclosure, the production method thereof, and the magnetic powder. The essence of this is as follows.

• <1> Magnetic connection with one by the formula:
  • (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e represented composition (in the formula,
    • R is one or more rare earth elements except Nd,
    • T is one or more elements selected from the group consisting of Ti, V, Mo and W,
    • M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au,
    • A is one or more elements selected from the group consisting of N, C, H and P,
    • 0 <x≤0,3,
    • 0≤y≤0,1,
    • 0≤z≤0,3,
    • 7.7 <a: 9.4,
    • b = 100 acd,
    • 3,1≤c <7.7,
    • 0: 5≤d≤1,0, and
    • 1≤e≤18)
    • satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3 and
    • has a ThMn ₁₂ -type crystal structure.
• <2> Magnetic connection according to item <1>, wherein in the formula 3,1≤c≤7,3.
• <3> Magnetic compound according to item <1> or <2>, wherein 7.7 <a≤8.7 in the formula.
• <4> Process for the preparation of the magnetic compound according to item <1>, comprising:
  • Preparing a molten metal having a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d (in the formula
    • R is one or more rare earth elements except Nd,
    • T is one or more elements selected from the group consisting of Ti, V, Mo and W,
    • M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au,
    • 0 <x≤0,3,
    • 0≤y≤0,1,
    • 0≤z≤0,3,
    • 7.7 <a: 9.4,
    • b = 100 acd,
    • 3,1≤c <7.7,
    • 0≤d≤1,0), and satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3,
    • Quenching the molten metal at a rate of 1 × 10 ² to 1 × 10 ⁷ K / sec to obtain a ribbon, and
    • Allowing A (one or more elements selected from the group consisting of N, C, H and P) to enter the band.
• <5> The method of item <4>, which further comprises pulverizing the strip before penetration to obtain a powder.
• <6> The method of item <5>, further comprising heat treating the strip at 800 to 1,300 ° C for 2 to 120 hours.
• <7> The method of item <5> or <6> further comprising heat-treating the powder at 800 to 1,300 ° C for 2 to 120 hours.
• <8> The method according to any one of the items <4> to <7>, wherein in the formula 3,1≤c≤7,3.
• <9> The method according to any of the items <4> to <8>, wherein in the formula 7.7 <a≤8.7.
• <10> Magnetic powder comprising a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e (in the formula
  • R is one or more rare earth elements except Nd,
  • T is one or more elements selected from the group consisting of Ti, V, Mo and W,
  • M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au,
  • A is one or more elements selected from the group consisting of N, C, H and P,
  • 0 <x≤0,3,
  • 0≤y≤0,1,
  • 0≤z≤0,3,
  • 7.7 <a: 9.4,
  • b = 100 acd,
  • 3,1≤c <7.7,
  • 0: 5≤d≤1,0, and
  • 1≤e≤18)
  • satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3 and
  • has a ThMn ₁₂ -type crystal structure.

[Effects of the Invention]

According to the present disclosure, the overall composition of the magnetic compound is specified by including the composition of the components in the magnetic phase, whereby the content of the α-Fe phase in the magnetic compound can be minimized. Thus, according to the present disclosure, a magnetic compound in which, coupled with an effect of nitriding, both the anisotropic magnetic field and the saturation magnetization are further increased, a manufacturing method thereof and a magnetic powder can be provided.

list of figures

• [ 1 ] 1 is a graph generated from the analysis results of Table 1, which collectively shows the relationship between the content of Zr content x and the content of a rare earth deposit or Ti content c with respect to the total composition of the magnetic compound in each of Examples 1 to 7 and FIG Comparative Examples 1 to 8th shows.
• [ 2 ] 2 is an Nd-Fe-Ti ternary phase diagram.
• [ 3 ] 3 Figure 4 is a graph showing the stability region of the T-constituent in the R'Fe _12-v T _v compound.
• [ 4 ] 4 Figure 12 is a schematic diagram of the device used for tape casting.
• [ 5 ] 5 Fig. 15 is a diagram showing an SEM image of the sample of the comparative example 5 illustrated.
• [ 6 ] 6 is a graph generated from Table 4, which collectively shows the relationship of the Zr content ratio x 'and the content p of the rare earth site with respect to the composition of the magnetic phase in each of Examples 1 to 7 and Comparative Examples 1 to 8th shows.

Embodiment of the Invention

The embodiments of the magnetic compound of the present disclosure, the method thereof, and the magnetic powder will be described in detail below. It should be noted here that the following embodiments do not limit the magnetic compound of the present invention, the production method thereof, and the magnetic powder.

The magnetic compound of the present disclosure has a ThMn ₁₂ type crystal structure. The magnetic compound of the present disclosure contains Nd, Fe and Ti as main elements, and therefore the composition with which the ThMn ₁₂ type crystal structure is likely stabilized will be described with reference to the Nd-Fe-Ti-ternary system.

2 illustrates an Nd-Fe-Ti ternary phase diagram ( Source: A. Margarian, et. al., Journal of Applied Physics, 76, 6153 (1994) ). Like from the 2 seen in the Nd-Fe-Ti-Nd ternary system, a can be a NdFe _12-w Ti _w phase, ₃ Fe _29-w Ti _w phase and a Nd ₂ Fe ₁₇ Ti _w-w-phase may be present. In 2 these phases are called "1:12", "3:29" and "2:17", respectively. Of these phases, the NdFe _12-w Ti _w phase has a ThMn ₁₂ -type crystal structure. The NdFe _12-w Ti _w phase includes, for example, an NdFe ₁₁ Ti phase. Incidentally, in the following, the NdFe _12-w Ti _w phase, the Nd ₃ Fe _29-w Ti _w phase and the Nd ₂ Fe _17-w Ti _w phase sometimes referred to as 1-12-phase, 3-29- Phase or 2-17 phase referred to.

In these phases, assuming that the Fe and Ti content 1 is the Nd content ratio (molar ratio) 0.083, 0.103 and 0.118 in the 1-12 phase, 3-29 phase and 2-17 phase, respectively. That is, in the 3-29 phase and the 2-17 phase, the content of the Nd content is high as compared with the 1-12 phase.

Like from the 2 Also, in the Nd-Fe-Ti ternary system, an α-Fe phase may be present in addition to the 1-12 phase, 3-29 phase and 2-17 phase. When the Nd content is 7.7 at.%, The highest stability of the 1-12 phase is likely to be achieved, and the .alpha.-Fe-phase content tends to decrease. When the content of Nd is less than 7.7 at.%, The 3-29 phase, 2-17 phase, etc., may hardly be present and the α-Fe phase content is likely to increase. On the other hand, if the content of Nd exceeds 7.7 at.%, The contents of the 3-29 phase, 2-17 phase, etc. are likely to increase, and the α-Fe phase content tends to decrease. Here, the "3-29 phase, 2-17 phase, etc." means the generic term of phases in which the Nd content is high compared to the 1-12 phase. Such a phase includes, except for the 3-29 phase and the 2-17 phase, for example, phases where part of Nd is absent in the 3-29 phase and 2-17 phase, and phases in which one small number of Nd atom continues to penetrate into the 3-29 phase and 2-17 phase.

As in 2 The composition range in which the 1-12 phase stably exists is very narrow. Accordingly, when the Nd content in the entire magnetic compound is reduced, the 1-12 phase is not stabilized, and the α-Fe phase content tends to increase. On the other hand, if the Nd content is increased, the 1-12 phase is also not stabilized, and the contents of the 3-29 phase, 2-17 phase, etc. tend to decrease.

Traditionally, to stabilize the 1-12 phase, Zr was added to the Nd-Fe-Ti ternary system. However, in terms of Zr content, investigations were made only to the extent of keeping the Zr content ratio (molar ratio) lower than the Nd content ratio (molar ratio) so as not to inhibit the activity and effect of Nd. Accordingly, for example, in the magnetic compound disclosed in Patent Document 1, the α-Fe phase content could not be sufficiently reduced.

In the magnetic compound, a magnetic phase and a grain boundary phase are present. The grain boundary phase has a mixture of different phases and is complicated. In addition, with respect to the magnetic properties of the magnetic compound, many properties are derived from the magnetic phase. Accordingly, the Zr content ratio in the magnetic phase was examined.

Although not bound by theory, it is believed that much of the Zr in the magnetic compound is partially substituted by Nd. Therefore, assuming that the total content of Nd and Zr in the magnetic phase was 1 , the relationship between the Zr content ratio (molar ratio) x 'and the total content (At%) p of Nd and Zr relative to the entire magnetic phase is examined.

As a result, the inventors found out the following.

The numerical values x 'and p in the magnetic phase are in a linear relationship (proportional relationship), and the gradient thereof is positive. This indicates that when the Zr ratio x 'in the magnetic phase is increased, the content p of the rare earth site represented by Nd _(1-xy) R _y Zr _x increases in the magnetic phase.

In addition, x 'in the magnetic phase is substantially equal to x. Accordingly, when x is designated as the Zr content ratio (molar ratio), it is assumed that the total content of Nd and Zr in the overall composition 1 and denoting a as the total content (At.%) of Nd and Zr in the overall composition, the relationship between them is examined. As a consequence, it has been found that, as in the case of the magnetic phase, when the Zr ratio x in the overall composition is increased, the content of a rare earth site represented by Nd _(1-xy) R _y Zr _x increases in the overall composition ,

In addition, it has been found that in the relationship between x and a, when a <1.6x + 7.7, the magnetic phase is not stabilized, and many α-Fe phases are present in the grain boundary phase. This corresponds to the fact that in the Nd-Fe-Ti ternary (no Zr contained) phase diagram, which in the 2 is illustrated, when the Nd content is small, the α-Fe phase content is likely to increase.

On the other hand, when a≥1.6x + 7.7, the content of the α-Fe phase present in the grain boundary phase decreases. It has also been found that in the grain boundary phase, a small amount of the 3-29 phase, 2-17 phase, etc. is present. This corresponds to the fact that in the Nd-Fe-Ti ternary (no Zr contained) phase diagram, which in the 2 that is, when the Nd content is large, the α-Fe phase tends to decrease and the 3-29 phase and the 2-17 phase are likely to be present.

On the preceding pages, the state of knowledge in the case of adding Zr to the Nd-Fe-Ti ternary system to stabilize the 1-12 phase has been described. In the following, the knowledge obtained by examining the Ti content for more stabilization of the 1-12 phase will be described.

In the magnetic compound, a magnetic phase and a grain boundary phase are present. The grain boundary phase has a mixture of different phases and is complicated. In addition, as with the magnetic properties of the magnetic compound, many properties are derived from the magnetic phase. The content of Zr in the magnetic phase was therefore first investigated.

Accordingly, assuming that the total content of Nd and Zr in the magnetic phase became 1 , the relationship between the Zr content ratio (molar ratio) x 'and the content (At%) q of Ti relative to the entire magnetic phase is examined.

As a result, the inventors found the following.

x 'in the magnetic phase is substantially equal to x in the overall composition. Accordingly, denoting x as the Zr content ratio (molar ratio), assuming that the total content of Nd and Zr in the overall composition 1 and denoting c as the content (at.%) of Ti in the overall composition, the relationship between them is examined. As a consequence, it was found that the content c of the rare earth site represented by Nd _(1-xy) R _y Zr _{x changes} in the overall composition with a change in the Zr ratio x in the overall composition.

In addition, it has been found that in the relationship between x and c, when c <-14x + 7.3, the magnetic phase is not stabilized and many α-Fe phases are present in the grain boundary phase. This corresponds to the fact that in the Nd-Fe-Ti ternary (no Zr contained) phase diagram illustrated in the 2 if the Nd content is small, the α-Fe phase content is likely to increase.

On the other hand, when c≥-14x + 7.3, the content of the α-Fe phase present in the grain boundary phase decreases. It has also been found that in the grain boundary phase a small amount of 3-29 phase, 2 17-phase etc. are available. This corresponds to the fact that in the Nd-Fe-Ti ternary (no Zr contained) phase diagram illustrated in the 2 if the Nd content is large, the α-Fe phase content tends to decrease, and the 3-29 phase and the 2-17 phase are likely to be present.

The constitutional requirements of the magnetic compound of the present disclosure, its production method, and the magnetic powder, which were provided on the basis of the previously discussed knowledge, etc., are described below.

«Magnetic connection >>

The magnetic compound of the present disclosure has a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e . This formula represents the overall composition of the magnetic compound of the present disclosure.

In the preceding formula, Nd is neodymium, R is one or more rare earth elements except Nd, Zr is zirconium, Fe is iron and Co is cobalt. T is one or more elements selected from the group consisting of Ti, V, Mo and W. Ti is titanium, V is vanadium, Mo is molybdenum and W is tungsten. M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au. Al stands for aluminum, Cr stands for chromium, Cu stands for copper, Ga stands for gallium, Ag stands for silver and Au stands for gold. A is one or more elements selected from the group consisting of N, C, H and P. N is nitrogen, C is carbon, H is hydrogen and P is phosphorus.

x and y are content ratios (molar ratios) of Zr and R, respectively, assuming that the entirety of the rare earth site represented by Nd _(1-xy) R _y Zr _x 1 is. In the rare earth station Nd is the remaining one after exclusion of R and Zr.

z is the co-content fraction (molar ratio) assuming that the entire iron group position represented by Fe _(1-z) CO _z 1 is. In the iron group office, Fe is the remaining one after exclusion of Co.

a, b, c and d are contents (At .-%) of the rare earth site, the iron group site, T and M, assuming that the whole represented by Nd _(1-xy) R _y Zr _x ) _a (Fe _{(1 z)} Co _{z) b} T _c M _d magnet compound precursor (of the magnetic connection of the present disclosure 100 at is .-%., in the total magnetic compound precursor is as b = 100 acd, the iron-group site remaining in the preceding formula by Exclusion of the rare earth site, T, and M. Then A is an element formed in the magnetic compound _precursor represented by (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) Co _z ) _b T _c M _d e is the content (At%) of A relative to the total magnetic compound precursor Accordingly, a + b + c + d + e exceeds 100 at%.

The constituent elements of the preceding formula will be described below.

<Nd>

Nd is a rare earth element and is an essential ingredient for the magnetic compound of the present disclosure to develop permanent magnet properties.

<R>

R is one or more rare earth elements except Nd. In the present invention, unless otherwise specified, the rare earth element is Y, Sc, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

In the magnetic compound of the present disclosure, the rare earth element in the magnetic compound is specified as Nd, and the content of Nd is specified, thereby minimizing the content of the α-Fe phase in the magnetic compound. In the raw material of Nd, it is difficult to completely eliminate the rare earth element R different from Nd. However, if the value of y in the rare earth site represented by Nd _(1-xy) R _y Zr _x is from 0 to 0.1, the properties of the magnetic compound of the present invention may be thought to be substantially equal to those when R is not is available.

The value of y is ideal 0 but an excessive increase in the purity of the raw material of Nd causes an increase in the manufacturing cost, and therefore, the value of y may be 0.01 or more, 0.02 or more, 0.03 or more, 0.04 or more, Be 0.05 or more. On the other hand, the value of y is preferably smaller as long as the purity of the raw material of Nd does not excessively increase, and therefore, the value of y may be 0.09 or less, 0.08 or less, 0.07 or less, or 0.06 or less be.

<Zr>

Part of Nd and / or R is substituted by Zr and this contributes to the stability of the ThMn ₁₂ type crystal structure. Contraction of a crystal lattice is caused by substitution of Nd and / or R in the ThMn ₁₂ -type crystal structure by Zr. In this way, even if the magnetic compound is adjusted to a high temperature (600 ° C or more) or a nitrogen atom, etc., to penetrate into the crystal lattice, the ThMn ₁₂ -type crystal structure is likely to be obtained. On the other hand, from the viewpoint of magnetic properties, a strong magnetic anisotropy originating from Nd is attenuated by the substitution of a part of Nd by Zr. Therefore, the Zr content is determined both from the viewpoint of the stability of the ThMn ₁₂ type crystal structure and the magnetic properties.

In order to stabilize the ThMn ₁₂ type crystal structure and suppress the decomposition of the magnetic compound at a high temperature, Zr is essential. Since the function and effect of Zr are recognized even at a small amount, the value of x in the rare earth location represented by Nd _(1-xy) R _y Zr _{x is} sufficient if it is more than 0. From the viewpoint of clearly enjoying the function and effect of Zr, the value of x may be 0.02 or more, 0.04 or more, 0.06 or more, or 0.08 or more. On the other hand, when the value of x is 0.3 or less, the anisotropic magnetic field is not extremely reduced. In addition, an Fe ₂ Zr phase can hardly be generated. The Fe ₂ Zr phase inhibits the evolution of coercive force when the magnetic compound is nitrided. If an Fe ₂ Zr phase can hardly be generated, the development of the coercive force is less likely to be inhibited. From these points of view, the value of x may be 0.28 or less, 0.26 or less, 0.24 or less, or 0.22 or less.

The total content of Nd, R and Zr described above is referred to as the content of the rare earth site represented by Nd _(1-xy) R _y Zr _x . When the content a of the rare earth site exceeds 7.7 at.%, Even if the magnetic compound is adjusted at a high temperature (600 ° C or more) or a nitrogen atom, etc. is caused to enter the crystal lattice, the ThMn ₁₂ -type crystal structure are hardly decomposed. When the ThMn ₁₂ type crystal structure is decomposed, the α-Fe phase content increases. Accordingly, if the ThMn ₁₂ type crystal structure can hardly be decomposed, the α-Fe phase content is likely to increase. From this viewpoint, the content of the rare earth site is preferably 7.8 at.% Or more, more preferably 7.9 at.% Or more, still more preferably 8.0 at.% Or more. On the other hand, when the content a of the rare earth site is 9.4 at.% Or less, the magnetic anisotropy of the magnetic compound can hardly be reduced. Since, when a large amount of Nd is substituted by Zr, a large amount of a phase other than the magnetic phase is generated, and the strong magnetic anisotropy derived from Nd is significantly reduced. From the viewpoint of suppression reduction of magnetic anisotropy, the content of the rare earth site is preferably 9.2 at.% Or less, more preferably 8.7 at.% Or less, still more preferably 8.5 at.% Or less.

In addition, as described above, in the overall composition of the magnetic compound, when the Zr content ratio x in the rare earth site and the content a of the rare earth site satisfy the relationship a≥1.6x + 7.7, the α-Fe phase content can be to 2% by volume or less relative to the entire magnetic compound. In addition, both the saturation magnetization and the anisotropic magnetic field of the magnetic compound after nitriding can be increased.

In the present specification, the α-Fe phase content is expressed in% by volume, which is measured in the following manner. The magnetic compound is embedded in a resin, polished and observed at a plurality of spots using an optical microscope or an SEM-EDX, and the average area ratio of the α-Fe phase in the viewing plane is measured by image analysis. The average area ratio means an average of the area ratios measured at individual viewpoints.

Assuming that the texture in the magnetic compound is not oriented in a specific direction, a relationship of S≈V between the average area ratio S and the volume ratio V is established. Accordingly, with respect to the α-Fe phase content, the value of the average area ratio (area%) of the α-Fe phase measured in the manner previously described as the α-Fe phase content (% by volume).

<T>

T is one or more elements selected from the group consisting of Ti, V, Mo and W. Corresponding elements of Ti, V, Mo and W may be considered to provide the same function and effect. The 3 Figure 13 is a diagram illustrating the stabilization region of T in the R'Fe _12-v T _v compound (R 'is a rare earth element) (Source: KHJ Buschow, Rep. Prog. Phys., 54, 1123 (1991)). It is from the 3 to understand that when Ti, V, Mo or W is added as a third element to the R'-Fe binary system, the ThMn ₁₂ -type crystal structure is stabilized and excellent magnetic properties are exhibited.

Conventionally, in order to obtain the stabilizing effect of the T component, the ThMn ₁₂ type crystal structure is formed by adding a large amount of T exceeding the necessary amount. Therefore, the content percentage of the Fe component constituting the magnetic compound decreases, and an Fe atom occupying site having a greatest effect on the magnetization is replaced with, for example, a T atom, causing a decrease in the total magnetization. In addition, when the T content is increased, Fe ₂ T is easily generated.

When the T content c is less than 7.7 at.%, The magnetization can hardly be reduced and Fe ₂ Ti is less likely to be generated. From these viewpoints, the T content c is preferably 7.5 at.% Or less, more preferably 7.3 at.% Or less, still more preferably 7.0 at.% Or less.

On the other hand, when the T content c is 3.1 at.% Or more, the ThMn ₁₂ -type crystal structure is easily stabilized. From this point of view, the content is preferably 3.5 at.% Or more, more preferably 4.0 at.% Or more, still more preferably 5.0 at.% Or more.

In addition, as described above, in the entire composition of the magnetic compound, the Zr content ratio x in the rare earth site and the T content c satisfies the relationship of c≥-14x + 7.3, the α-Fe phase content may to 2% by volume or less relative to the entire magnetic compound. In addition, both the saturation magnetization and the anisotropic magnetic field of the magnetic compound after nitriding can be increased.

<M>

M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au. The unavoidable impurity indicates an impurity that is inevitably contained or causes a significant increase in manufacturing cost while avoiding its inclusion, such as an impurity contained in a raw material of the magnetic compound or an impurity mixed in a production step. The unavoidable impurity element includes Si and / or Mn, etc.

M (excluding an unavoidable impurity element) contributes to the suppression of grain growth of a ThMn ₁₂ type crystal or the viscosity or melting point of a phase other than the phase having a ThMn ₁₂ type crystal structure (for example, a grain boundary phase), but is not essential for the magnetic compound of the present disclosure.

The M content d is 1.0 at% or less. When the M content d is 1.0 at% or less, the content percentage of an Fe component constituting the magnetic compound decreases, and hence the decrease in the total magnetization is less likely to occur. From this viewpoint, the M content d is preferably 0.8 at.% Or less, more preferably 0.6 at.% Or less, still more preferably 0.4 at.% Or less.

On the other hand, from the viewpoint of clearly enjoying the function and effect of M (including an unavoidable impurity element), the M content is preferably 0.1 at.% Or more, more preferably 0.2 at.% Or more, more preferably 0.3 at.% Or more. In addition, in the case of not containing one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au, the M content is the content of an unavoidable impurity. The content of an unavoidable impurity is preferably smaller, but an excessive decrease in the content of unavoidable Contamination causes, for example, an increase in the manufacturing cost, and therefore, a small amount of an unavoidable impurity may be contained in the range that produces substantially no effect on the magnetic properties, etc., of the magnetic interconnection. From this point of view, the lower limit of the M content d may be 0.05 at.%, 0.1 at.% Or 0.2 at.%.

<Fe and Co>

In the magnetic compound of the present disclosure, the remaining one after the exclusion of the previously described element is Fe, but a part of Fe may be substituted by Co. In the case where a part of Fe is substituted by Co, a part of Fe in the α-Fe phase is substituted by Co. In the present specification, when a phase is described as α-Fe phase, the α-Fe phase includes a phase in which a part of the Fe of the α-Fe phase is substituted by Co.

Substitution of a part of Fe by Co causes an increase in spontaneous magnetization according to the Slater-Pauling rule, and produces an effect of increasing both the properties of the anisotropic magnetic field and the saturation magnetization. In addition, substitution of a part of Fe by Co causes an increase in the Curie point of the magnetic compound, and thus is effective in suppressing the reduction of the magnetization at a high temperature.

For the clear enjoyment of these effects, assuming that the entirety of the iron group site represented by Fe _{(1-z) 3} CO _z 1 is, the Co content ratio (molar ratio) z is preferably 0.05 or more, more preferably 0.10 or more, still more preferably 0.15 or more.

On the other hand, if the Co content is excessive, the effect according to the Slater-Pauling rule can hardly be obtained. When the content of Co content (molar ratio) z is 0.30 or less, the effect is less likely to be alleviated according to the Slater-Pauling rule. From this point of view, the Co content ratio (molar ratio) z is preferably 0.26 or less, more preferably 0.24 or less, still more preferably 0.20 or less.

<A>

A is one or more elements selected from the group consisting of N, C, H, and P. A can expand the lattice of the ThMn ₁₂ phase by penetrating into the crystal lattice of the ThMn ₁₂ phase and exhibit both the properties of the anisotropic magnetic field and the Increase saturation magnetization. The A content e is from 1 to 18 at.%. When the A content e is 1 at.% Or more, the lattice of the ThM ₁₂ phase can be extended. From the viewpoint of extending the lattice of the ThMn ₁₂ phase, the A content e is preferably 5 at.% Or more, more preferably 7 at.% Or more, still more preferably 8 at.% Or more. When the A content e is 18 at% or less, the content percentage of an Fe component constituting the magnetic compound is not excessively decreased. If the content percentage of the Fe component is not excessively reduced, it is unlikely that the stability of the ThMn ₁₂ phase will be impaired, a part of the magnetic compound will be decomposed, and the magnetization will be lowered. From the viewpoint of suppressing the reduction in magnetization, the A content e is preferably 14 at% or less, more preferably 12 at% or less, still more preferably 10 at% or less.

<Crystal Structure>

The magnetic compound of the present disclosure has a ThMn ₁₂ type crystal structure. The ThMn ₁₂ -type crystal structure is tetragonal. In X-ray diffraction (XRD) with a Cu source, the ThMn ₁₂ type crystal structure shows the strongest X-ray diffraction intensity when 2θ is 42.36 ° ((321) plane) and shows a weak X-ray diffraction intensity when 2θ is 33 ° ((310) -Level).

In the ThMn ₁₂ -type crystal structure, when the X-ray diffraction intensity at 2θ is from 42.36 ° ((321) plane) through I _c (321) and the X-ray diffraction intensity at 2θ is from 33 ° ((310) plane) through I _c (310), which is I _c (310) 13.2, assuming I _c (321) is 100.

It is known that when the ThMn ₁₂ -type crystal structure collapses (is disturbed), the structure changes to a Th ₃ Mn ₂₉ -type crystal structure. In X-ray diffraction (XRD) with a Cu source, the Th ₃ Mn ₂₉ type crystal structure shows the strongest X-ray diffraction intensity when 2θ is 42.35 ° ((-133) plane), and shows a weak X-ray diffraction intensity when 2θ is 33 ° is ((302) -plane).

In the Th ₃ Mn ₂₉ -type crystal structure, when the X-ray diffraction intensity at 2θ is 42,35 ° ((-133) plane), I _c (-133) and the X-ray diffraction intensity at 2θ is 33 ° ((302 ) Level is denoted by I _c (302), I _c (302) is 5.9, assuming that I _c (-133) is 100.

From this, the ThMn ₁₂ may be type crystallinity, indicating the fraction of the ₁₂ ThMn -type crystal structure in the magnetic connection defined by {I _m (310) -I _c (302)} / {I _c (310) -I _c (302)}. Here, I _m (310) is the measured value of the X-ray diffraction intensity on the (310) plane for the magnetic compound. When the crystal structure is of a complete ThMn ₁₂ type, the ThMn ₁₂ type crystallinity is 100%, and when the crystal structure is of a complete Th ₃ Mn ₂₉ type, the ThMn ₁₂ type crystallinity is 0%.

In the magnetic compound of the present disclosure, the ThMn ₁₂ type crystal structure preferably occupies 50% or more, that is, the ThMn ₁₂ type crystallinity is preferably 50% or more. When the ThMn ₁₂ type crystallinity is 50% or more, the ThMn ₁₂ type crystal structure in the magnetic compound is stabilized, and hence the α-Fe phase can hardly increase. In view of the stability of the ThMn ₁₂ type crystal structure, the ThMn ₁₂ type crystallinity is preferably higher, and is preferably 60% or more, 70% or more, 80% or more, or 90% or more. On the other hand, the ThMn ₁₂ type crystallinity can not be 100%, and may be 98% or less, 96% or less, 94% or less, or 92% or less.

As described in the foregoing pages, according to the magnetic compound of the present disclosure, the content of the α-Fe phase in the magnetic compound can be minimized, and after nitriding, both the saturation magnetization and the anisotropic magnetic field can be further increased.

The magnetic compound of the present invention may be used as a raw material for sintered magnets and bonded magnets, or the magnetic compound may also be used directly as a magnetic powder.

<< Magnetic Powder >>

In the case of using the magnetic compound as a magnetic powder, the magnetic powder has a composition represented by the formula: (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e
(in the formula,
R is one or more rare earth elements except Nd,
T is one or more elements selected from the group consisting of Ti, V, Mo and W,
M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au,
A is one or more elements selected from the group consisting of N, C, H and P,
0 <x≤0,3,
0≤y≤0,1,
0≤z≤0,3,
7.7 <a: 9.4,
b = 100 acd,
3,1≤c <7.7,
0: 5≤d≤1,0, and
1≤e≤18)
satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3 and
has a ThMn ₁₂ -type crystal structure.

<< Preparation Process >>

The manufacturing method of the present disclosure includes a molten metal preparing step, a molten metal quenching step, and an A-element penetrating step. These steps will be described one after the other in the following.

<Preparing step for molten metal>

In the magnetic compound of the present disclosure, the total composition of the magnetic compound prior to nitriding and the composition of a molten metal prepared at the time of preparation of the magnetic compound are substantially the same. With regard to the composition of a molten metal is not considered that the molten metal components due to evaporation, etc. are consumed in the process of holding / solidifying the molten metal. In the case where consumption of the molten metal components occurs depending on the production conditions, etc., the raw materials may be mixed in consideration of consumption.

In the case where consumption of the molten metal need not be taken into consideration, a molten metal having a formula represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d prepared composition. In the formula, Nd, R, Zr, Fe, Co, T and M are the same as the contents described for the magnetic compound. In addition, both x, y and z and a, b, c and d are the same as those described for the magnetic compound. In the previous formula, the relationships of a≥1.6x + 7.7 and c≥-14x + 7.3 are satisfied.

<Detering Step of Molten Metal>

A molten metal having the foregoing composition is quenched at a rate of 1 × 10 ² to 1 × 10 ⁷ K / sec. Upon quenching, it is likely that the ThMn ₁₂ -type crystal structure is stabilized and the α-Fe phase content is minimized.

For the quenching method, for example, the molten metal may be melted at a predetermined rate in accordance with a strip casting method by using one of the methods described in U.S. Pat 4 illustrated quenching device 10 be cooled. In the quenching device 10 the raw materials are in a smelting furnace 11 melted to a molten metal 12 to prepare with the preceding composition. The molten metal 12 becomes a tundish at a fixed feed rate 13 fed. The molten metal 12 fed to the tundish 13 becomes a chill roll 14 from one end of the tundish 13 fed by its own weight.

The tundish 13 consists of a ceramic, etc., and can temporarily the molten metal 12 pick up that continuously from the smelting furnace 11 is supplied at a predetermined flow rate, and improves the flow of the molten metal 12 to the chill roll 14 , In addition, the tundish has 13 also a function of adjusting the temperature of the molten metal 12 immediately before reaching the chill roll 14 on.

The chill roll 14 is formed of a material having high thermal conductivity, such as copper or chromium, and the surface of the cooling roll 14 is subjected to chromium plating, etc. to avoid erosion with the high-temperature molten metal. The chill roll 14 can be rotated in the arrow direction by a drive device (not shown) at a predetermined rotational speed. By controlling the rotation speed, the cooling speed of the molten metal can be controlled to a speed of 1 × 10 ² to 1 × 10 ⁷ K / sec.

When the cooling rate of the molten metal is 1 × 10 ² K / sec or more, it is possible to stabilize the ThMn ₁₂ -type crystal structure and facilitate the minimization of the α-Fe phase content. From this viewpoint, the cooling rate of the molten metal is more preferably 1 × 10 ³ K / sec or more. On the other hand, when the cooling speed of the molten metal is 1 × 10 ⁷ K / sec or less, in spite of saturation of the effect achieved by quenching, the molten metal can not be cooled at a higher speed than necessary. The cooling rate of the molten metal may be 1 × 10 ⁶ K / sec or less or 1 × 10 ⁵ K / sec or less.

The molten metal 12 at the outer periphery of the chill roll 14 Chilled and solidified is called a band 15 from the chill roll 14 detached and collected by a collection device. If desired, the band 15 powdered using an end mill, etc. to obtain a powder.

<A-element penetration step>

An A-element is brought into the band 15 penetrate. The A element is one or more elements selected from the group consisting of N, C, H and P. In view of the ease of penetration of the A element, the penetration of the A element preferably occurs after pulverization of the belt 15 ,

In the case where the A element is nitrogen, the penetration of the A element is done by heating and nitriding the tape 15 at 200 to 600 ° C for 1 to 24 hours using, for example, a nitrogen gas, a mixed gas of nitrogen gas and hydrogen gas, an ammonia gas, or a mixed gas of ammonia gas and hydrogen gas as a nitrogen source.

In the case where the A element is carbon, the band becomes 15 and carbonated at 300 to 600 ° C for 1 to 24 hours using, for example, a C ₂ H ₂ (CH ₄ , C ₃ H ₈ , CO) gas or a thermolysis gas of methanol as a carbon source. In addition, solid carbonization using a carbon powder or molten salt carbonization using KCN or NaCN may be employed. Similarly, for H and P, normal hydrogenation or phosphidation can be performed.

<Heat Treatment Step>

In addition, in the manufacturing method of the present disclosure, the tape obtained in the previous step may 15 be heat treated at 800 to 1300 ° C for 2 to 120 hours. By this heat treatment, the phase having a ThMn ₁₂ type crystal structure (hereinafter sometimes referred to as "ThMn ₁₂ phase") is homogenized and both anisotropic magnetic field and saturation magnetization properties are further increased. The pulverization of the tape 15 can be done before the heat treatment or can be done after the heat treatment.

When the heat treatment temperature is 800 ° C or more, the ThMn ₁₂ phase can be homogenized. In view of the homogenization of the ThMn ₁₂ phase, the heat treatment temperature is preferably 900 ° C or more, more preferably 1,000 ° C or more, still more preferably 1,100 ° C or more. On the other hand, when the heat treatment temperature is 1,300 ° C or less, the texture of the magnetic compound is unlikely to be decomposed and an α-Fe phase is generated. From this viewpoint, the heat treatment temperature is preferably 1,250 ° C or less, more preferably 1,200 ° C or less, still more preferably 1,150 ° C or less.

[Examples]

The magnetic compound of the present disclosure, the production method thereof and the magnetic powder will be described below more specifically by reference to Examples and Comparative Examples. The magnetic compound of the present disclosure, the production method thereof and the magnetic powder are not limited to the conditions used in the following examples.

<< Preparation of the sample >>

A sample of the magnetic compound was prepared in the following manner.

A molten metal having the composition shown in Table 1 was prepared and prepared at a rate of 10 ⁴ K / sec according to a strip casting method to prepare a quenched strip, and heat treatment was carried out at 1200 ° C for 4 hours in an Ar atmosphere , Subsequently, in an Ar atmosphere, the belt was pulverized by an end mill, and particles having a particle diameter of 20 μm or less were collected. These particles were placed in a nitrogen gas having a purity of 99.99% at 450 ° C for 4 hours, thereby subjected to nitriding.

<< Evaluation of the sample >>

The size and area ratio of the α-Fe phase were measured from an SEM (reflected electron image) image of the obtained particle (before nitriding), and the α-Fe phase content (% by volume) was expressed as an area ratio = Volume ratio calculated. In addition, X-ray diffraction (XRD) of the obtained particle was carried out, and the ThMn ₁₂ -type crystallinity was calculated by the method previously described. In addition, the amount of nitrogen and the magnetic properties of the obtained particle (after nitriding) were measured. The amount of nitrogen was calculated from the change in weight between before and after nitriding.

The saturation magnetization and the anisotropic magnetic field of the obtained particle (after nitriding) were measured on the basis of the saturation-asymptotic law using a vibrating sample magnetometer (VSM). As the vibrating sample magnetometer (VSM) became a Magnetometer capable of applying a magnetic field of up to 9T (7.2 mA / m). The measuring sample was prepared by packing the particles after nitriding in a container made of acrylic resin (inner dimension: 5 mm in diameter and 5 mm in height) and securing the particles with a paraffin resin.

The results (before nitration) are shown in Table 1. In Table 1, based on the total composition of the magnetic compound, a sample of the magnetic compound was collected and analyzed by ICP emission spectrum analysis. For M, since a trace of unavoidable impurities has been detected, details for the M content are shown in Table 2. In Table 2, ppm ppm is on the mass. The analysis results of Table 1 were substantially the same for the composition of the charged molten metal. The 1 Fig. 12 is a graph created from the analysis results in Table 1, which collectively shows the relationship of the Zr content rate x and the content a of the rare earth site or the Ti content c with respect to the total composition of the magnetic compound in each of the examples 1 to 7 and Comparative Examples 1 to 8 shows. [Table 1] Total Composition of Magnetic Compound Before Nitration (Expressed as At%) (Nd _(1-xy) R _y Zr _x ) (Fe _(1-z) Co _z ) _b Ti _c M _d α-Fe phase content ThMn ₁₂ - type crystallinity Disintegration of Magnetic Bond Due to Exposure to High Temperature (600 ° C or More) Other x y a z c d 1.6x + 7.7 -14x + 7.3 (Vol. -%) (-) (-) (-) example 1 0.10 Tr. 8.26 0.30 6.12 <1 7.86 5.90 0.9 91.8 none - Example 2 0.10 Tr. 8.19 0.10 6.12 <1 7.86 5.90 0.9 60.3 none - Example 3 0.10 Tr. 8.40 0.30 6.87 <1 7.86 5.90 0.8 86.3 none - Example 4 0.20 Tr. 8.05 0.20 5.36 <1 8.02 4.50 1.5 95.9 none - Example 5 0.20 Tr. 8.05 0.30 5.36 <1 8.02 4.50 0.6 90.4 none - Example 6 0.30 Tr. 8.19 0.30 6.12 <1 8.18 3.10 1.7 93.2 none - Example 7 0.30 Tr. 9.09 0.30 6.06 <1 8.18 3.10 1.2 67.1 none - Comparative Example 1 0 Tr. 8.12 0.30 5.44 <1 7.70 7.30 0.9 70.6 decomposable - Comparative Example 2 0.10 Tr. 7.69 0.25 5.77 <1 7.86 5.90 3.0 75.5 none - Comparative Example 3 0.10 Tr. 8.19 0.10 4.59 <1 7.86 5.90 5.6 56.8 none - Comparative Example 4 0.20 Tr. 7.69 0.20 5.77 <1 8.02 4.50 6.0 96.0 none - Comparative Example 5 0.40 Tr. 9.09 0.30 6.06 <1 8.34 1.70 * 32.8 none Fe ₂ Zr phase was generated Comparative Example 6 0.30 Tr. 8.14 0.30 5.36 <1 8.18 3.10 5.2 78,30 none - Comparative Example 7 0.20 Tr. 7.70 0.25 5.80 <1 8.02 4.50 3.2 73.4 none - Comparative Example 8 0.30 Tr. 7.70 0.25 5.80 <1 8.18 3.10 2.9 77.5 none - Note 1) "Tr." Indicates that the content is below the measurement limit. Note 2) "*" Indicates that no data has been collected. Note 3) "-" indicates that there is no relevant item. [Table 2] Al (mass%) Si (mass%) Ni (ppm) C (ppm) O (ppm) example 1 0.2 0 123 50 142 Example 2 0.1 0.1 141 43 127 Example 3 0.1 0 117 58 139 Example 4 0.1 0 98 47 121 Example 5 0.2 0.1 124 44 138 Example 6 0.2 0 146 51 132 Example 7 0.1 0 113 42 144 Comparative Example 1 0.1 0 109 59 119 Comparative Example 2 0.1 0.1 122 43 142 Comparative Example 3 0.2 0 138 44 122 Comparative Example 4 0.1 0 104 52 118 Comparative Example 5 0.2 0.1 116 48 137 Comparative Example 6 0.1 0 128 46 124 Comparative Example 7 * * * * * Comparative Example 8 * * * * * Note) "*" indicates that no data has been collected.

As shown in Table 1 and the 1 As can be seen, in the samples of Examples 1 to 7 where the total composition of the magnetic compound is in the correct range, it was confirmed that the α-Fe phase content is 2 vol% or less. In addition, it could be confirmed in Examples 1 to 7 that the ThMn ₁₂ type crystallinity was 50% by volume or more.

On the other hand, in the samples of Comparative Examples 2 to 4 and 6 to 8, where the total composition of the magnetic compound is not in the correct range, it was confirmed that the α-Fe phase content exceeded 2 vol%.

In the sample of Comparative Example 1, the α-Fe phase content was 2 vol% or less, but Zr is not contained in the magnetic compound (z = 0), and when exposed to high temperature (600 ° C) the magnetic compound is decomposed to produce an α-Fe phase.

In the sample of Comparative Example 2, where the Zr content ratio x at the rare earth site represented by Nd _(1-xy) R _y Zr _x exceeded the upper limit of the present invention, an Fe ₂ Zr phase was generated. The 5 FIG. 15 is a diagram illustrating an SEM image of the sample (before nitriding) of Comparative Example 5. FIG. In the 5 the generation of Fe ₂ Zr phase is observed at the positions indicated by arrows.

With respect to the overall composition of the magnetic compound, there is a method wherein each of the contents of the rare earth site, the iron group site, Ti and M is expressed in at.%, And a method where the content is expressed by the molar ratio. As a reference, Table 3 shows the total composition (before nitration) of the magnetic compound by both methods. Incidentally, since it is very small, the M content was omitted to express the M content by the molar ratio. [Table 3] Total Composition of Magnetic Compound Before Nitration (Expressed as At%) (Nd _(1-xy) R _y Zr _x ) (Fe _(1-z) Co _z ) _b Ti _c M _d Total composition of the magnetic compound before nitration (expressed as molar ratio) (Nd _(1-xy) R _y Zr _x ) _r (Fe _(1-Z) Co _Z ) _(12-t) Ti _t x y a z c d 1.6x + 7.7 -14x + 7.3 x y r z t example 1 0.10 Tr. 8.26 0.30 6.12 <1 7.86 5.90 0.10 Tr. 1.08 0.30 0.80 Example 2 0.10 Tr. 8.19 0.10 6.12 <1 7.86 5.90 0.11 Tr. 1.07 0.10 0.80 Example 3 0.10 Tr. 8.40 0.30 6.87 <1 7.86 5.90 0.09 Tr. 1.10 0.30 0.90 Example 4 0.20 Tr. 8.05 0.20 5.36 <1 8.02 4.50 0.20 Tr. 1.05 0.20 0.70 Example 5 0.20 Tr. 8.05 0.30 5.36 <1 8.02 4.50 0.20 Tr. 1.05 0.30 0.70 Example 6 0.30 Tr. 8.19 0.30 6.12 <1 8.18 3.10 0.30 Tr. 1.07 0.30 0.80 Example 7 0.30 Tr. 9.09 0.30 6.06 <1 8.18 3.10 0.30 Tr. 1.20 0.30 0.80 Comparative Example 1 0 Tr. 8.12 0.30 5.44 <1 7.70 7.30 0 Tr. 1.06 0.30 0.71 Comparative Example 2 0.10 Tr. 7.69 0.25 5.77 <1 7.86 5.90 0.10 Tr. 1.00 0.25 0.75 Comparative Example 3 0.10 Tr. 8.19 0.10 4.59 <1 7.86 5.90 0.10 Tr. 1.07 0.10 0.60 Comparative Example 4 0.20 Tr. 7.69 0.20 5.77 <1 8.02 4.50 0.20 Tr. 1.00 0.20 0.75 Comparative Example 5 0.40 Tr. 9.09 0.30 6.06 <1 8.34 1.70 0.40 Tr. 1.20 0.30 0.80 Comparative Example 6 0.30 Tr. 8.14 0.30 5.36 <1 8.18 3.10 0.30 Tr. 1.04 0.30 0.70 Comparative Example 7 0.20 Tr. 7.70 0.25 5.80 <1 8.02 4.50 0.20 Tr. 1.00 0.25 0.75 Comparative Example 8 0.30 Tr. 7.70 0.25 5.80 <1 8.18 3.10 0.30 Tr. 1.00 0.25 0.75 Note) "Tr." Indicates that the content is below the measurement limit.

The magnetic compound has a magnetic phase and a grain boundary phase. When the EPMA-ZAF method is used, the composition of the magnetic phase can be measured by its separation from the composition of the grain boundary phase. In Table 4, the measurement results of the composition of the magnetic phase are collectively shown with respect to the magnetic compound before nitriding. In Table 4, the overall composition of the magnetic compound shown in Table 1 is shown together. In addition, in Table 4, the composition of the magnetic phase is shown by both a method in which the contents of the rare earth site, the iron group site and Ti are expressed as At% and a method where the content is expressed by the molar ratio. Incidentally, since the M content is very small, the composition of the magnetic phase was shown by omitting the M content.

The 6 is a graph generated from Table 4, which collectively shows the Zr content ratio x 'and the content p of the rare earth site with respect to the composition of the magnetic phase in each of Examples 1 to 7 and Comparative Examples 1 to 8th shows.

Like from the 6 As can be seen, it was confirmed that the composition of the magnetic phase in each of Examples 1 to 7 and Comparative Examples 1 to 8th is in a linear relationship (proportional relationship), and the gradient of it is positive.

The magnetic properties of the magnetic compound after nitriding are shown in Table 5. [Table 5] Total composition of the Magnetic Compound after nitration (At%) (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z Co _z ) _b Ti _c M _d A _e saturation magnetization Anisotropic magnetic field x y a z c d e (T) (MA / m) example 1 0.10 Tr. 8.26 0.30 6.12 <1 6.43 1.56 6.42 Example 2 0.10 Tr. 8.19 0.10 6.12 <1 8.28 1.58 6.82 Example 3 0.10 Tr. 8.4 0.30 6.87 <1 10.24 1.57 6.67 Example 4 0.20 Tr. 8.05 0.20 5.36 <1 7.70 1.55 6.99 Example 5 0.20 Tr. 8.05 0.30 5.36 <1 5.39 1.61 6.63 Example 6 0.30 Tr. 8.19 0.30 6.12 <1 8.06 1.60 6.32 Example 7 0.30 Tr. 9.09 0.30 6.06 <1 9.85 1.59 6.78 Comparative Example 1 0 Tr. 8.12 0.30 5.44 <1 4.62 1.58 5.90 Comparative Example 2 0.10 Tr. 7.69 0.25 5.77 <1 10.78 1.62 5.94 Comparative Example 3 0.10 Tr. 8.19 0.10 4.59 <1 8.69 1.60 5.82 Comparative Example 4 0.20 Tr. 7.69 0.20 5.77 <1 10.78 1.55 5.73 Comparative Example 5 0.40 Tr. 9.09 0.30 6.06 <1 Not measured due to low cristalinity Comparative Example 6 0.30 Tr. 8.14 0.30 5.36 <1 10.39 1.63 5.87 Comparative Example 7 0.20 Tr. 7.70 0.25 5.80 <1 9.24 1.62 5.25 Comparative Example 8 0.30 Tr. 7.70 0.25 5.80 <1 10.31 1.58 5.08 Note 1) "Tr." Indicates that the content is below the measurement limit.

As can be seen from Table 5, it was confirmed that in the samples of Examples 1 to 7, a high anisotropic magnetic field of 6.32 to 6.99 (MA / m) can be obtained, while a high saturation magnetization of 1.55 to 1.61 T is preserved. It is believed that this is due to the fact that the α-Fe phase content in the magnetic compound is 2 vol% or less. Incidentally, the α-Fe phase content of the magnetic compound is considered to be the same before and after nitriding.

In addition, as shown in Table 5, in all samples, the anisotropic magnetic field is 7.2 MA / m or less, and since this value is not more than the maximum applied magnetic field 9 T (Fig. 2 mA / m) of the vibrating sample magnetometer (VSM) used, the saturation magnetization and the anisotropic magnetic field in all samples could be measured correctly.

As a reference, with respect to a value measured by using a vibrating sample magnetometer having a maximum applied magnetic field of 5 T (4 MA / m), the saturation magnetization and the anisotropic magnetization of Comparative Examples 7 and 8 were determined from the results of a sample by extrapolation the saturation magnetization and the anisotropic magnetic field were known, and the following results were obtained.

Comparative Example 7:

Saturation magnetization: 1.56 T, anisotropic magnetic field: 7.6 MA / m

Comparative Example 8

Saturation magnetization: 1.57 T, anisotropic magnetic field: 7.8 MA / m

Both samples showed a higher value than that measured using a vibrating sample magnetometer (VSM) with a maximum applied magnetic field 9 T (7.2 mA / m).

From the foregoing, the effects of the magnetic compound of the present disclosure, its production method and the magnetic powder could be verified.

A magnetic compound having a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e (in the formula, R is one or more rare earth elements except for Nd, T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is an unavoidable impurity element, etc., A is one or more elements selected from the group consisting of N, C, H and P, 0 <x≤0,3, 0≤y≤0,1, 0≤z≤0,3, 7,7 <a: 9,4, b = 100-acd, 3,1≤c <7 , 7, 0≤d≤1,0, and 1≤e≤18, in the formula satisfies the relationships a≥1.6x + 7.7 and c≥-14x + 7.3, and having a ThMn ₁₂ type crystal structure , a manufacturing method thereof and a magnetic powder.

LIST OF REFERENCE NUMBERS

10

Abschreckgerät

11

furnace

12

molten metal

13

tundish

14

chill roll

15

tape

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• Source: A. Margarian, et. al., Journal of Applied Physics, 76, 6153 (1994) [0013]

Claims (10)

A magnetic compound having a composition represented by the formula: (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e (in the formula, R is one or more Rare earth elements other than Nd, T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au, A is one or more elements selected from the group consisting of N, C, H and P, 0 <x≤0.3, 0≤y≤0.1, 0≤z≤0.3, 7.7 <a: 9.4, b = 100-acd, 3.1≤c <7.7, 0: 5≤d≤1.0, and 1≤e≤18) satisfies, in the formula, the relationships a ≥ 1.6x + 7.7 and c≥-14x + 7.3 and has a ThMn ₁₂ -type crystal structure. Magnetic connection to Claim 1 where in the formula is 3.1≤c≤7.3. Magnetic connection to Claim 1 or 2 , where 7.7 <a≤8.7 in the formula. Process for the preparation of the magnetic compound according to Claim 1 process comprising: preparing a molten metal having a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d (in the formula, R is a or more rare earth elements except Nd, T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga , Ag and Au, 0 <x≤0.3, 0≤y≤0.1, 0≤z≤0.3, 7.7 <a: 9.4, b = 100-acd, 3.1≤c <7.7, 0≤d≤1.0), and satisfies, in the formula, the relationships a≥1.6x + 7.7 and c≥-14x + 7.3, quenching the molten metal at a rate of 1 × 10 ² to 1 × 10 ⁷ K / sec to obtain a tape and allow A (one or more elements selected from the group consisting of N, C, H and P) to enter the tape. Method according to Claim 4 which further comprises pulverizing the tape prior to penetration to obtain a powder. Method according to Claim 5 which further comprises heat treating the strip at 800 to 1300 ° C for 2 to 120 hours. Method according to Claim 5 or 6 which further comprises heat treating the powder at 800 to 1300 ° C for 2 to 120 hours. Method according to one of Claims 4 to 7 where in the formula is 3.1≤c≤7.3. Method according to one of Claims 4 to 8th , where 7.7 <a≤8.7 in the formula. A magnetic powder comprising a composition represented by the formula (Nd _(1-xy) R _y Zr _x ) _a (Fe _(1-z) CO _z ) _b T _c M _d A _e (in the formula, R is one or more Rare earth elements except Nd, When T is one or more elements selected from the group consisting of Ti, V, Mo and W, M is unavoidable impurity elements and one or more elements selected from the group consisting of Al, Cr, Cu, Ga, Ag and Au, A is one or a plurality of elements selected from the group consisting of N, C, H and P, 0 <x≤0.3, 0≤y≤0.1, 0≤z≤0.3, 7.7 <a: 9.4 , b = 100-acd, 3.1≤c <7.7, 0: 5≤d≤1.0, and 1≤e≤18) satisfies, in the formula, the relationships a≥1.6x + 7 , 7 and c≥-14x + 7.3 and has a ThMn ₁₂ -type crystal structure.

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