JPS6022648B2 - oxide magnetic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an oxide magnetic material used as a substrate for microwave devices or microwave elements such as circulators and isolators used in microwave regions such as VHF, UHF, and SHF bands. .

In general, the characteristics required of magnetic materials used in microwave devices are that the ferromagnetic resonance absorption half-maximum △day is narrow, the required saturation magnetization (4 戀Ms) is appropriate, and the temperature coefficient is extremely high. 4. That's right. As is well known, the magnetic resonance frequency is
Z)4汀MS〕〔日　（NX１NZ）四刀MS〕｝1ノ2.

Here, day is the external magnetic field, Nx, Ny, and Nz are the demagnetizing field coefficients in each of the x, y, and z directions, and there is a relationship of Nx+Ny+Nz=1. Furthermore, it is the gyromagnetic ratio. Therefore, if the element is a sphere, Nx=Ny=Nz, and is 4T Ms
4m when used in a shape other than a sphere.
A change in Ms directly results in a change in the mountain. When the element is actually used in a circulator or isolator, the temperature coefficient Q' must be 0.1%/°C or less in the range of -20 to 60 oo. However, Q is Q = (cloth S) 20 Yozo, (4mMs) 20 is the 4th Ms value at 20oo, and △4mMs is the difference between the maximum and minimum values of saturation magnetization in the temperature range. It is.

Recently, however, the temperature coefficient Q has been required to be small over a wider temperature range. Generally, garnet has the chemical formula {n}[&](C3)○,2, where A, B, and C represent elements occupying 24c, 18, and 24 lattice points, respectively.

Particularly in magnetic garnet, magnetic ions occupy some or all of these lattice points. The magnetic alignment is {A
}[B] (C) The magnetic moments are parallel in each sublattice, and [B] and (C) are coupled antiparallel. Also, {A}
and (C) are connected in antiparallel. Therefore, the temperature change in the saturation magnetization is the vector sum of the temperature changes in the saturation magnetization of the sublattices of {A}[B](C). Therefore, in order to reduce the temperature change in saturation magnetization, either the temperature change in each sublattice is reduced, or the temperature change in saturation magnetization as a sum is reduced. Yttrium-iron garnet (Y.1.G) has conventionally been used as a microwave material. However, the temperature coefficient Q' of 4 Ms, {A}
is a non-magnetic yttrium ion, the temperature change in total magnetization is the difference between the magnetizations of [B] and (C), and the temperature -
The Q (hereinafter referred to as "Q") in the range of 20 to 60 qo is as large as about 0.2%/°C. Furthermore, the temperature is 120 to 100o
o and Q in a wide range (hereinafter referred to as Q2) is approximately 0.3%
/°C. However, Q2 is ・●-2o~l
oo.

In the range of 0, Q2 = (4 bamboo Ms) 20. The back ≦ the bookmark, (4 side MS) 4mMs value at 20G and 20℃, △
4Ms is the difference between the maximum value and the minimum value of saturation magnetization in the temperature range.

In addition, the currently narrowest ferromagnetic resonance absorption half-maximum value of △day has been reported for Ca-V-ln substituted Y. 1. In G, Q
, reaches about 0.4%/°C, and Q2 reaches about 0.5%/°C.

Therefore, when creating a microwave device using these materials, the element is generally made of magnetic shunt steel or magnetic shunt ferrite, and is used in a constant temperature range or in a constant salt bath. is taken. On the other hand, {A}'s it! By replacing the umion with the magnetic ion gadolinium, it becomes possible to have a magnetization cancellation point where the magnetization of the sublattice cancels each other out.

Since the magnetization is zero between this cancellation point and the Curie temperature (TC), the temperature change in saturation magnetization can be made small in the temperature range between them. For example, A. S. Huds
There is a report on garnet with the composition Gda Y3-2ra Ca2xFe5li-y-zVxkaway○,2 by On et al. (1.E.E.E.TransactIonon
NnegnetS,V. 1, Mag-5, N.

31969P610-613) However, the temperature coefficient Q here is as large as about 0.24%/°C at the minimum, and about 0.35%/°C for Q2, and means such as temperature compensation is required in practice.

Therefore, the present invention provides Gd-Ca-V-ln substituted Y. 1.0
In order to further reduce the temperature coefficient of saturation magnetization, the temperature coefficient of saturation magnetization can be reduced by selecting a composition such that the temperature at which the saturation magnetization is maximum between the magnetization cancellation point and the Curie temperature is -25 to 35 oo. Temperature coefficient Q,,Q2
The objective is to reduce both to extremely small values of 0.1%/°C or less. That is, the feature of the present invention is {C&Y3-2X? Ca2×}[Fer
ylny](Fe3-XVx)0,2, in which 0<xSO. 7 0.05≦y≦0.25 0.35 mm2.0 However, in the composition range of 127SI5 ratio -22W+12board SI87, the saturation magnetization 4T Ms between the magnetization cancellation point and the Curie temperature is , the maximum temperature is -25~35qo
It is an oxide magnetic material in the range of .

The reason why the ln amount y is limited to 0.05≦y≦0.25 is that when y is 0.05 or less, the ferromagnetic resonance absorption half value △day increases rapidly, and when y is 0.25 or more, the This is because the temperature coefficients Q, Q2 become large even if Tmax is set in the range of -25 to 35°C due to the decrease in the temperature coefficient. Further, if the V amount x is 0.7 or more, it becomes difficult to bond, resulting in a decrease in density. Furthermore, the range of the Gd amount z is naturally determined by determining the ranges of the above-mentioned ln amount y and V amount x, and in order to satisfy the above conditions, the range is 0.35 mS2.0. Also,
4mMs temperature coefficient Q,,Q2 are both 0.1%/00
In order to do the following, x, y, z must be 127 SI 5 - 22, 112 SI 87.

The present invention will be explained in detail below with reference to Examples. Example 1
{Gd,. 2Y,. 8-Public C too} [Fe, . 91 no.
,](Fe3-XVx)○,2, x=0.15
, 0.25, 0.35, 0.50.
3, Y203, CaC03, Fe203, 1 mountain 03, V
24 or hydroxides, trates, carbonates, etc. which decompose to form the above oxides were weighed to the above composition ratio and mixed in a ball mill.

Afterwards, it was temporarily held at 800 to 1250 qo for 1 to 6 hours, finely ground again in a pole mill, and after compression molding at 1280 to 1450 C.
Calcination was performed in an oxygen atmosphere for 0.5 to 8 hours. As a result of examining the obtained samples by X-ray diffraction, it was confirmed that all the samples were single-phase garnet. Next, using a magnetic balance, the temperature change in saturation magnetization was measured from the liquid N2 temperature to the Curie temperature. Then, the temperature Tm at which 4Template Ms becomes maximum
ax and temperature coefficient Q of 4mMs, (-20~6000
) and Q2 (range of -20 to 10,000) were measured. These results are shown in Table 1. - As is clear from Table 1, Tmax increases as x increases and shifts by about 11500/0.1 molecular formula.

On the contrary, 4mMs shows a decreasing tendency.

Tc decreases monotonically. Temperature coefficient Q of 4 sword Ms. teeth,
It becomes the smallest when x is around 0.25, and Q2 becomes the smallest when x is around 0.3.

Example 2 {Gd, . 2YMC fever. 7} [Fe2-yiny] (F
e2.6V〇. 35) ○, 2, y=0.05,
GQ〇3, Y2 so that it becomes 0.1, 0.2, 0.25
Samples were prepared in the same manner as in Example 1 using raw materials of 〇3, CaC〇3, Fe2〇3,1 to 〇3, V2Q.

Table 2 shows the measurement results of each characteristic value of this sample. As is clear from Table 2, Tmax shows a tendency to decrease as y increases, shifting by about 122° C./0.1 molecular formula.

4 Bamboo Ms increases as y increases, and Tc conversely decreases.

The temperature coefficient Q, of 4mMs is minimum when y is 0.2.

Q2 is minimum when y is 0.1. However, when y is 0.3, Q2 is greater than 0.1%/°C. Example 3 {MzY2.3-ZCa.

．． 7} [Fe,. 91n. ．． , ] (Fe2.65V..
35) In ○, 2, Z=0.8, 1.0, 1.2,
A sample was prepared using the same raw materials and preparation method as in Example 1 so that the following results were obtained. Table 3 shows the results of measuring various properties of the sample. As is clear from Table 3, as the amount of z increases, Tma
x increases and moves about 11200/0.1 molecular formulas.

On the contrary, 4mMs shows a decreasing tendency, and Tc shows a slight upward trend.

Also, when the temperature coefficient Q, is 1.0, Q2 is z
It is minimum when the amount is 1.2. From Examples 1 to 3 above,
Figure 1 shows the relationship between the temperature Tmax at which 4mMs is maximum between the magnetic cancellation point and the Curie temperature and the temperature coefficients Q, Q2.
Shown in Figure 2.

First, from Figure 1, no matter which value of x, y, or z is changed, when Tmax is 10°C, Q is extremely small at 0.03%/°C, and even if the temperature is between -32 and 3500 BaQ
, as small as 0.1%/℃. Next, in Figure 2, x, y,
No matter which z is changed, if Tmax is 2000, it is 2]
It is extremely small at 0.042%/00. (In both Figures 1 and 2, 0 indicates the value when x, x indicates y, and △ indicates z.) From the above, it can be seen that Q, Q2 are both 0.
It can be seen that in order to obtain a very small temperature coefficient of 1%/°C or less, the temperature of Tmax should be in the range of -25 to 3500.

From now on, x, y, z and Tmax are {GyaY3-2X
-2Ca public} [Fe2-yiny] (Fe3-XV×)
If it is 0,2, it can be expressed as Tmax=15, 122, 112, 152. Therefore, Tmax is -2
To be between 5 and 3500, -25 SI5 melon -2
Any value of x, y, and z that satisfies 2-112-152S35 may be used.

Next, embodiments of the present invention will be described by way of examples.

Example 4 {Gdl. 4Y1, 28C father. 32 } [
Fel, 91nM] (Fe2.84V.

．． ,6)○,2For this composition, x=0.16, y=0.
1, z = 1.4, 15 melon - 22's 112th place = 170.

A sample was prepared using the same raw materials and preparation method as in Example 1 using the above composition ratio. The temperature change in the saturation magnetization 4 Ms of the obtained sample was measured from the liquid N2 temperature to Tc. As a result, 4mMs at 20qo = 871G, Tmax = 18
qo, temperature coefficient Q, = 0.042%/°C, Q2 = 0.
048%/00 and the conventional Ca-V-ln substitution Y. 1.
It is one order of magnitude smaller than G. Example 5 {Gdl, 59Y1, Field C, 32} [Fel, 81n
o. 2] (Fe2.84V〇.16>.

12 In this composition, x=0.16 y=0.2, z=1.5
915 melon - 22W + 12th place = 171.

A sample was prepared in the same manner as in Example 1 using this composition ratio. As a result of measuring the characteristic values of the obtained sample, 4T Ms = 8583, Tmax = -15q0, Q, at 20qo:
0.054%/°C, and Q2 = 0.080%/°C. Example 6 {Gd, . Mouse Y,. 2C too. ,6}[F
e,. 91 nM] (Fe2.92V〇.).

12 In this composition, x=0.08, y=0.1, z=1.6
The 112th place of 415 cucumbers and 22 = 186.8.

A sample was prepared in the same manner as in Example 1 using this silk composition ratio.
As a result of measuring the characteristic values of the obtained sample, 4 at 20qo
Inside MS Ni808G, TmaX Ni340. ,QI 〇.
〇98%/℃, Q2! It was 0.081%/00.
From the above results, {G& Y3-2x-zCa2x}
Fe2-yiny] (Fe3-xVx)○,2, when the ln amount y is 0.05≦y≦0.25, -25
SI5 melon-22 112 mountains-152S35 x
, y, z, the temperature coefficient Q, (-2
0 to 60 qo) and Q2 (120 to 100 qo) are both extremely small at 0.1%/°C or less. Here, the first face (
Q for special face 148976 (1976) is 0.08%/0
0 or less, but Q2 is at least 0.135%/00
It is. In comparison, in the oxide magnetic material of the present invention, by setting the ln amount y to 0.05 to 0.25, a microwave ferrite with a high Tc and a small temperature coefficient over a wide temperature range of -20 to 100 oo can be obtained. It will be done. Therefore, when used in circulators, isolators, etc., it is possible to create devices that are extremely stable over a wide temperature range.

[Brief explanation of the drawing]

Figures 1 and 2 show the temperature Tmax and 4Ms at which 4Ms is maximum between the magnetic cancellation point and Tc by changing the values of x, y, and z.
Temperature coefficient Q, (range of -20 to 60 qC), Q
2 (range from -20 to 10pi0). Figure 2

Claims (1)

[Claims] 1. Compositional formula {GdzY_3_-_2_x_-_zCa_
2x} [Fe_2-yIny] (Fe_3-xVx)O
_1_2, and in the above compositional formula, 0<x≦
0.7 0.05≦y≦0.25 0.35≦z≦2.0 However, 127≦150x-220y+120z≦18
7, and the temperature at which the saturation magnetization (4πMs) is the highest between the magnetization cancellation point and the Curie temperature is -
An oxide magnetic material characterized by a temperature range of 25 to 35°C.