JPS6019126B2 - microwave ferrite - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a Ca-V garnet used for microwave circuit elements, and has a saturation magnetic flux density (hereinafter referred to as 4mMs) of 14.
Microphone with values from 00 Gauss to 1900 Gauss.

It concerns wave ferrite. The desired characteristics of the magnetic material used in these irreversible elements are
The most necessary conditions are that the magnetic loss is small, the magnetic loss is small, and the temperature change of the four bamboo Ms is small. Currently, the most commonly used microwave ferrite for irreversible elements is Y-Fe (YIG)-based garnet. Its feature is that it has a low M content of 4mM compared to conventional spinel ferrites such as Ni-Zn ferrite and Mn-Mg ferrite.
s, a material with a high Curie temperature and low loss.
However, as communications via satellites become more active, it is required that the loss be as low as possible for irreversible elements used in microwave input/output circuits such as weak microwave amplifiers on board satellites and at earth stations. be done. In particular, the present invention relates to ferrite for nonreciprocal elements used in frequency bands above the X band. The YIG system has a ferromagnetic resonance absorption half-width (hereinafter referred to as △day), which is a measure of magnetic loss, for commonly used materials, and is around △H = 40 Oe, which is suitable for low loss related to satellite communications. In some cases, the required element has a large loss and is difficult to put into practical use.

The present invention eliminates these drawbacks and has excellent characteristics such as a small Δ day and a high Curie temperature, which meet the demands. To obtain these materials, Ca3-yYyFe
3.5-small 5 x 10 o. Rule SnxV,. 5-o. 5x-o
．． In other words, it is a composition expressed by a chemical formula of 0,2, and the values of x and y are each 0.01SxSO. 5, 2.5<y≦2.
It is characterized by being within a composition range satisfying 99.

Examples will be described in detail below. First, the sample was Ca3-yYyFe3.5-o. 5x+o. SeiSnxV
、． 5-o. 5x-o. With a composition of ○, 2, depending on the composition CaCo3, Fe203, V2Q, Y203, Sn0
Weighed various amounts of 2 and mixed them in a steel ball mill.950
After 00-necessary dawning and compression molding, each composition was fired at the lowest firing temperature of 1.300oo~1.450°C for 1 unique time, and 4 Ms, △day, (9. Yesterday at Z) measurement)
, the Curie temperature was measured.

Example 1 Ca3-yYyFe3.5-o. Defeat-o. 5ySnxV
、． 5-o. 5x-o. Table 1 shows the characteristics when the value of y is variously changed when x=0.1 with the composition according to Rule ○, 2.

Tables 1 and above As shown in Table 1, in each composition, it is possible to provide a nonreciprocal circuit element with very small Δday and low loss.

When y<2.5, 4Ms becomes smaller than 1400 Gauss, which is beyond the purpose of the present invention, so the effective range of y is y>2.
．． It is 5. Example 2 CayyYyFe3.5- or string + o. 5ySnxV,.
5-o. Table 2 shows the characteristics when the Y and Sn substitutions are changed in the composition of 5x-Small Rule ○, 2.

As shown in Table 2 above, Δday decreases rapidly with Sn substitution.

In other words, with Sn substitution, when x = o, the characteristic of △H = 38 oersteds becomes approximately 1/M · 6.0 oersteds when x = 0.2, and 3.1 oersteds when x = 0.4, and x = oersteds. The value is shown as 1/IM. It is clear that this is an excellent material for low-loss nonreciprocal circuit elements. Sn
The effective range of substitution is that when x = 0.01 or less, the effect is small, and when x > 0.6, the Curie temperature is low and the temperature change of 4 　Ms is large. Therefore, the valid range is 0.01SxSO
．． It is in the range of 05. As described above, the microwave ferrite Ca-V type ferrimagnetic garnet of the present invention has a lower △day compared to the conventionally used microwave ferrite yttrium-iron-aluminum type garnet, and has a It is an excellent material for low-loss irreciprocal circuit elements for frequency domain satellite communications.

In this way, the Y-Sn substitution of Ca-V garnet
3-yYyFe3.5-Kodori Konori SnxV,. 5-o.
5x-o. In the chemical formula of kalpa○, 2, 2.5<y≦2.
99,0.01SxSO. Within the composition range of No. 5, a material with low loss can be provided as a microwave circuit element.

Note that the dielectric loss tan6 of the material of the present invention is 8×10-4
Small as below.

Claims (1)

[Claims] 1 Ca_3-_yY_yFe_3_・_5_-_0_
・＿5＿x＿＋＿0＿・＿5＿ySnxV_1＿・＿5
＿−＿0＿・＿5＿x＿−＿0＿・＿5_yO_1_2
In the composition formula represented by 2.5<y≦2.99,0
．． A microwave ferrite having a composition that satisfies the condition 01≦x<0.3, a saturation magnetic flux density of 1400 to 1900 Gauss, and a ferromagnetic resonance absorption half width of 40 Oersteds or less.