JP2958809B2 - Microwave / millimeter wave magnetic composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a magnetic composition used in a high frequency region such as a microwave or a millimeter wave.

<Prior Art> Conventionally, Mn-Mg ferrite, Ni-Zn ferrite, lithium ferrite, YIG ferrite and the like have been used as high frequency magnetic materials.

These are excellent materials having a saturation magnetization (4πMs) of 500 to 4000 Gauss.

Among these, YIG ferrite is U.S. Pat.
As shown in No. 05, a composition consisting of Y ₃ Fe ₅ O ₁₂
Since the temperature coefficient (α) of 4πMs and 4πMs can be changed by substituting Gd and A, a material having a value of 4πMs most suitable for the frequency to be used can be selected and used in combination with a permanent magnet. In this case, it is an excellent material that can compensate the temperature characteristics of the magnet, and is a material that can be applied to highly stable circuit elements such as isolators and circulators.

Also, according to U.S. Pat. No. 3,419,496, this material is as low as 7.0 × 10 ⁸ Ω · cm volume resistivity [rho, when increased the [rho to 4.9 × 10 ¹² Ω · cm by the addition of MnO ₂ Have been. Furthermore, according to Japanese Patent Publication No. 60-55970,
It is said that the ferromagnetic resonance absorption half width (ΔH) can be reduced to 16 Oersted when the mixing ratio of the raw materials Y ₂ O ₃ and Fe ₂ O ₃ is 38.63 to 39.45 mol% and 61.37 to 60.55 mol%, respectively. I have.

<Problems to be Solved by the Invention> However, YIG ferrite has ΔH and dielectric loss (t
It has the disadvantage that loss values such as anδ) become so large that they cause practical problems due to subtle compositional fluctuations.
In addition, when this material is used as a phase conversion element, a high residual magnetic flux density (Br) is required, but there is a problem that as br increases, tan δ also increases.

The present invention in consideration of the above problems, has been made for improving the drawbacks of the conventional YIG ferrite, Y _w Fe _8-w O
Gd is a part of Y of the YIG ferrite represented by the general formula ( ₁₂ ).
So that α can be set to any value, and Fe
Is replaced with A so that 4πMs can be set to an arbitrary value, and a part of Fe is replaced with Mn, and at the same time, indium oxide is added to realize a very small value of ΔH. By fixing the ratio of site to Fe site in a very limited narrow range, large Br value and small ta
An object of the present invention is to provide a magnetic material for microwaves and millimeter waves that simultaneously realizes the value of nδ.

The present inventors <Means for Solving the Problems> As a result of intensive studies to solve the above problems, the YIG ferrite represented by the general formula of _{Y w Fe 8-w O 12} , part of the Fe site Is substituted with Mn, and at the same time, by adding indium oxide, a very small ΔH can be obtained.Furthermore, the ratio w of the Y site to the Fe site is large in a very narrow region between 3.02 and 3.06.
It is the finding that tan δ can be realized simultaneously.

That is, the magnetic material composition for microwaves / millimeter waves of the present invention provides (Y _1-x Gd _x ) _w (Fe
_1-yz A _y Mn _z ) In the composition represented by _8-w O ₁₂ , x,
y, z and w are respectively 0 ≦ x ≦ 0.35, 0 ≦ y ≦ 0.1
6. Mainly a composition in the range of 0.01 ≦ z ≦ 0.04, 3.02 ≦ w ≦ 3.06, to which indium oxide expressed in the form of In ₂ O ₃ is added in an amount of 0.2 mol% or more and 1.0 mol% or less. It is characterized by becoming.

<Operation> According to the present invention, 4πMs can be arbitrarily set in the range of 370 to 1780 Gauss, and therefore, a material having a value of 4πMs most suitable for the frequency to be used can be selected.

Further, since α can be arbitrarily set in the range of −960 to −2800 ppm / ° C., the temperature characteristics of the magnet can be compensated when used in combination with a permanent magnet or the like.

Furthermore, since Br is high and the loss values such as ΔH and tnaδ are extremely small, it is possible to obtain a magnetic material for microwaves and millimeter waves suitable for application to a latching type phase converter, a high precision isolator and a circulator. it can.

With respect to the objects, features and advantages of the invention described above,
Hereinafter, embodiments will be described with reference to the drawings.

<Examples> First, high-purity Y ₂ O ₃ , Fe ₂ O ₃ , Gd ₂ O ₃ , A
₂ O ₃ , MnO ₂ and In ₂ O ₃ were prepared. These raw materials were weighed so that the compositions shown in Tables 1, 2 and 3 were obtained, and were wet-mixed in a ball mill for 16 hours. After drying this mixture, it was calcined at 1050 ° C. for 2 hours to obtain a calcined product.
The calcined product was placed in a ball mill together with an organic binder, and wet-pulverized for 16 hours. After drying this pulverized product, 50
Granulate through a mesh net and weigh 2000 kg / c
prismatic and outer diameter 36mm of 3 mm × 3 mm × 20 mm at a pressure of m ^2, the inner diameter
It was formed into a ring having a thickness of 24 mm and a thickness of 6 mm. These moldings are
After calcining at 460-1490 ° C for 8 hours, the prismatic sintered body is machined to form a 1.3 mm diameter sphere and 1.3 mm diameter, length
A 16 mm cylindrical sample was obtained.

The temperature coefficient (α) of 4πMs and Curie temperature (Tc) of the obtained spherical sample were measured using a vibrating magnetometer at 4πMs and 4πMs, and ΔΔ at 10 GHz was measured in a TE106 cavity.
H was measured.

The tan δ at 10 GHz of the cylindrical sample was measured using a perturbation method in a TM101 cavity.

Further, a toroidal coil was formed by winding the conducting wire on the ring-shaped sample by bifilar winding, and the residual magnetic flux density (Br) and coercive force (Hc) at 100 Hz were measured.

Table 1 shows that the composition represented by (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z ) _8-w O ₁₂ varies x and y, and is in the form of In ₂ O ₃ It is a measurement result when the addition amount of indium oxide shown was changed. The asterisks in Table 1 are outside the scope of the present invention, and all others are within the scope of the present invention. Further, the composition range of the experimental example shown in Table 1 was changed to the first range.
It is shown in the composition diagram of the figure. The numbers in this drawing represent each sample number. In FIG. 1, a region having a composition ratio within the range of the present invention is indicated by a square having vertices A, B, C, and D.

Here, x and y of the composition represented by (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z ) _8-w O ₁₂ are respectively 0 ≦ x ≦ 0.3
5, the reason for limiting the range to 0 ≦ y ≦ 0.16 will be described.

If y exceeds 0.16 as in sample numbers 7, 14, 21 and 25, Br decreases and Tc decreases, which is not preferable.

Further, as in Sample Nos. 22, 23, 24 and 25, x is 0.35
Exceeds ΔH, which is not preferred because ΔH increases.

Next, the reason why the addition amount of indium oxide expressed in the form of In ₂ O ₃ is limited to 0.2 mol% or more and 1.0 mol% or less will be described.

First, in Sample Nos. 2, 9 and 16, the amount of In ₂ O ₃ added was 0%.
It is an example of mol% and is excluded from the scope of the present invention.

As shown in sample numbers 3, 10 and 17, the amount of In ₂ O ₃ added was 0.2
If the amount is less than mol%, the effect of improving ΔH is not remarkable, and is excluded from the scope of the present invention.

As shown in Sample Nos. 5, 12 and 19, the amount of In ₂ O ₃ added was 1.0
If it exceeds mol%, ΔH increases and Br decreases, which is not preferable.

Next, Table 2 shows that (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z )
It is a measurement result when changing Z of the composition represented by _8-w O ₁₂ .

Sample Nos. 26 to 30 in Table 2 correspond to Sample No. 4 in Table 1.
The sample Nos. 31 to 35 in Table 2 were obtained by changing Z for the composition of Sample No. 11 in Table 1, and the samples in Table 2 were changed in Z. Number 36 ~
Reference numeral 40 denotes the composition of Sample No. 18 in Table 1 in which Z was changed.

The asterisks in Table 2 are outside the scope of the present invention, and all others are within the scope of the present invention. The composition ranges of the experimental examples shown in Table 2 are shown in the composition diagram of FIG. 1 as in Table 1. The numbers in this drawing represent each sample number.

Here it will be described the reason for limiting the _{(Y 1-x Gd x)} w (Fe 1-yz A y Mn z) 8-w O 12 in a composition represented, ≦ z ≦ 0.04 0.01 a Z.

When Z is 0.01 or less as in sample Nos. 26, 31, and 36, ΔH is undesirably large.

When Z is 0.04 or less as in sample numbers 30, 35 and 40, ΔH is undesirably large.

Finally, Table 3 shows that (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z )
It is a measurement result when changing W of the composition represented by _8-w O ₁₂ .

The sample numbers 41 to 45 in Table 3 correspond to the sample number 4 in Table 1.
The sample Nos. 46 to 50 in Table 3 were obtained by changing W for the composition of Sample No. 11 in Table 1, and the samples in Table 3 were obtained by changing W. Number 51-
55 shows the results obtained by changing W for the composition of sample No. 18 in Table 1.

The asterisks in Table 3 are outside the scope of the present invention, and all others are within the scope of the present invention. The composition ranges of the experimental examples shown in Table 3 are shown in the composition diagram of FIG. 1 as in Tables 1 and 2. The numbers in this drawing represent each sample number.

Here, Table 3 have been selected for the reasons in the range of _{(Y 1-x Gd x)} w (Fe 1-yz A y Mn z) 8-w O a composition represented by _12, W and 3.02 ≦ w ≦ 3.06 This will be described with reference to FIG.

When W is 3.02 or less as in sample numbers 41, 46, and 51, tan δ increases, which is not preferable.

When W is 3.06 or more as in sample numbers 45, 50 and 55, ΔH increases and Br decreases, which is not preferable.

FIG. 2 shows (Y _1-x Gd _x ) _w (F
e _1-yz A _y Mn _z ) _8-w O ₁₂ common logarithm of W and tanδ (log
3 illustrates the relationship between tan δ) and Br. As is clear from FIG. 2, a large Br and a small tan δ can be simultaneously realized only when W is in the range of 3.02 ≦ w ≦ 3.06. The numbers in FIG. 2 represent each sample number.

As described in detail above, the microwave / millimeter-wave magnetic composition according to the present invention has a sufficiently small ΔH and a sufficiently small tan δ, and has a high Tc and a large Br. It is a very useful material for application to circuit elements such as phase shifters, highly stable isolators and circulators. Furthermore, (Y _1-x Gd _x ) _w (Fe
_1-yz A _y Mn _z ) x and y represented by the chemical formula of _8-w O ₁₂
Is appropriately changed within the scope of the present invention, whereby 4
πMs can be set arbitrarily in the range of 370 to 1780 Gauss, and α can be set arbitrarily in the range of -960 to 2800 ppm / ° C. Therefore, it is possible to select a material having a value of 4πMs most suitable for the frequency to be used, and to compensate for the temperature characteristics of the magnet when used in combination with a permanent magnet or the like.

[Brief description of the drawings]

FIG. 1 shows the composition of x and y of (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z ) _8-w O ₁₂ of the magnetic composition for microwave and millimeter wave according to the present invention. FIG. 2 is a composition diagram showing the range, and FIG. 2 is (Y _1-x Gd _x ) _w (Fe _1-yz A) for sample numbers 46 to 50 in Table 3.
_y Mn _z ) _8-w O ₁₂ common logarithm of W and tan δ (log tan δ)
4 is a graph showing the relationship between Br and Br.

Claims (1)

(57) [Claims] (1) (Y _1-x Gd _x ) _w (Fe _1-yz A _y Mn _z ) _8-w O ₁₂
In the composition represented by x, y, z and w are respectively 0 ≦ x ≦ 0.35, 0 ≦ y ≦ 0.16, 0.01 ≦ z ≦ 0.04, and 3.
The main component is a composition in the range of 02 ≦ w ≦ 3.06.
0.2% by mole or more of indium oxide expressed in the form of ₂ O ₃ ; 1.
A magnetic material composition for microwave / millimeter wave, containing 0 mol% or less.