JP2010083689A - Polycrystalline ceramic magnetic material, microwave magnetic substance, and non-reversible circuit component using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polycrystalline ceramic magnetic material which can be subjected to low temperature firing and co-firing with a metallic material of low resistance, has no formation of a hetero-phase even in a Bi-substituted type, and has a small ferromagnetic resonance half band width and a small dielectric loss, to provide a microwave magnetic substance, and to provide a non-reversible circuit component using the same. <P>SOLUTION: The polycrystalline ceramic magnetic material comprises a main component having a composition represented by the general formula (Y<SB>3.0-x-y-z</SB>Bi<SB>x</SB>Ca<SB>y</SB>Gd<SB>Z</SB>)(Fe<SB>5-α-β-γ</SB>In<SB>α</SB>Al<SB>β</SB>V<SB>γ</SB>)O<SB>12</SB>, wherein x, y and z satisfy 0.5≤x≤0.9, 0.5≤y≤0.9 and 0≤z≤0.4, respectively; and α, β and γ satisfy 0.05≤α≤0.4, 0≤β≤0.45 and 0.25≤γ≤0.45, and comprises Cu, Zr and Fe as accessory components, wherein the content of Cu expressed in terms of CuO is 0.1-0.5 wt.%, the content of Zr expressed in terms of ZrO<SB>2</SB>is 0.05-0.5 wt.% and the content of Fe expressed in terms of Fe<SB>2</SB>O<SB>3</SB>exceeds 0 and not larger than 1.0 wt.%, based on 100 wt.% of the main component. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a magnetic material for microwaves used for high-frequency circuit components, and further relates to a polycrystalline ceramic magnetic material that can be simultaneously fired with electrode materials such as silver and copper.

  In recent years, miniaturization of devices has been demanded with the progress of communication technology using electromagnetic waves in the microwave region, such as car phones, mobile phones, and satellite broadcasts. For this purpose, there is an increasing demand for downsizing and low profile of individual parts constituting the equipment.

  As typical high-frequency circuit components used in the field of communication equipment, for example, there are microwave nonreciprocal circuit elements such as circulators and isolators. In general, an isolator has a function such that there is almost no attenuation in the signal transmission direction and the attenuation is increased in the opposite direction. For example, a cellular phone, a car phone, etc. used in the microwave band and the UHF band. This is used in a transmission / reception circuit of a mobile communication device.

  Non-reciprocal circuit elements such as a circulator and an isolator include a central conductor having a plurality of electrode lines arranged in a state of being insulated from each other, a microwave magnetic body disposed in close contact with the central conductor, the central conductor and The central conductor assembly made of the magnetic material for microwaves includes a permanent magnet that applies a DC magnetic field, and the central conductor and the magnetic material for microwaves are manufactured as separate parts. Conventionally, various forms have been proposed, such as winding a copper foil around a microwave magnetic body, or printing and sintering a silver paste on the microwave magnetic body to form an integral body.

In order to meet the demands for downsizing as described above, for example, as described in Patent Document 1, as a material for the central conductor, a conductive paste formed by mixing a conductive powder such as palladium or platinum and an organic solvent is used. It has been proposed that the microwave magnetic material and the central conductor are integrally fired at a temperature of 1300 to 1600 ° C.
JP-A-6-61708

  The above-mentioned palladium or platinum has a high melting point of 1300 ° C. or higher and has an advantage that it can be easily fired integrally with most magnetic materials for microwaves, but has a high specific resistance. For example, when used for an isolator element, There is a disadvantage that the insertion loss is increased.

When low resistance silver or copper is used, a polycrystalline ceramic magnetic material in which Bi is substituted may be used so that simultaneous firing is possible. However, Bi oxide has a lower melting point than oxides of other constituent elements, and sometimes precipitates as a heterogeneous phase at the grain boundary without being taken into the crystal lattice.
In general, a microwave magnetic material with a narrow single-phase region, such as garnet, is prone to generation of a different phase or an increase in the amount of vacancies, but Bi is prominent. Garnet's ferromagnetic resonance half width ΔH and dielectric loss tan δ are increased. Moreover, it is not preferable in the appearance state due to the different color tone.

  Further, although the microwave non-reciprocal circuit element is used in combination with a permanent magnet, it is ideal that the temperature characteristic of the saturation magnetization 4πMs of the microwave magnetic material compensates the temperature characteristic of the permanent magnet.

  Therefore, the present invention solves the above-described problems and can be fired at a low temperature of 860 ° C. or higher and lower than 950 ° C., suppresses the generation of heterogeneous phases even in the Bi substitution type, and reduces the ferromagnetic resonance half width ΔH and dielectric loss. An object is to provide a polycrystalline ceramic magnetic material having a small tan δ and a temperature coefficient αm and a saturation magnetization of 4πMs so as to compensate for the temperature characteristics of a permanent magnet, a microwave magnetic material, and a nonreciprocal circuit device using the same. And

The first invention, the table in the main component is represented by the general formula _{(Y 3.0-x-y-} z Bi x Ca y Gd z) (Fe 5-α-β-γ In α Al β V γ) O 12 And the values of x, y, z are 0.5 ≦ x ≦ 0.9, 0.5 ≦ y ≦ 0.9, 0 ≦ z ≦ 0.4, and α, β, The value of γ is in the range of 0.05 ≦ α ≦ 0.4, 0 ≦ β ≦ 0.45, 0.25 ≦ γ ≦ 0.45, and contains Cu, Zr and Fe as subcomponents, The content of Cu is 0.1 wt% ≦ CuO ≦ 0.5 wt% in terms of CuO and Zr is 0.05 wt% ≦ ZrO ₂ ≦ 0 in terms of ZrO ₂ with respect to 100 parts by weight of the main component. A polycrystalline ceramic magnetic material characterized by 0.5 wt% and Fe in terms of Fe ₂ O ₃ 0 wt% <Fe ₂ O ₃ ≦ 1.0 wt%.

  The polycrystalline ceramic magnetic material according to the present invention has a saturation magnetization 4πMs of 70 mT to 110 mT and a temperature coefficient αm of −0.35% / ° C. to −0.21% / ° C. It is also characterized in that the value width ΔH is 8000 A / m or less.

  A second invention is a microwave magnetic body obtained by integrally sintering the polycrystalline ceramic magnetic material of the first invention and a conductor paste containing either Ag or an Ag alloy, and the microwave magnetism A microwave magnetic body comprising an electrode pattern formed of the conductive paste inside and / or on the surface of a body.

  According to a third aspect of the present invention, there is provided a capacitor connected to the central conductor, the electrode pattern formed on the microwave magnetic body according to the second aspect of the invention, and a ferrite magnet that applies a DC magnetic field to the microwave magnetic body. This is a non-reciprocal circuit device.

  The ferrite magnet preferably has a residual magnetic flux density Br of 420 mT or more and a temperature coefficient of −0.15% / ° C. to −0.25% / ° C.

  According to the present invention, firing can be performed at a low temperature of 860 ° C. or more and less than 950 ° C., and simultaneous firing with a low-resistance metal material such as silver or copper is possible. A polycrystalline ceramic magnetic material having a small magnetic resonance half width ΔH and a dielectric loss tan δ, a microwave magnetic material, and a nonreciprocal circuit device using the same can be provided.

Polycrystalline ceramic magnetic material of the present invention, the main component is represented by the general formula _{(Y 3.0-x-y-} z Bi x Ca y Gd z) (Fe 5-α-β-γ In α Al β V γ ) has a composition represented by _{O 12,} x, y, z values are located at 0.5 ≦ x ≦ 0.9,0.5 ≦ y ≦ 0.9,0 ≦ z ≦ 0.4 , Α, β, γ are in the range of 0.05 ≦ α ≦ 0.4, 0 ≦ β ≦ 0.45, 0.25 ≦ γ ≦ 0.45, and Cu and Zr as subcomponents And Fe, and the content of Cu is 0.1 wt% ≦ CuO ≦ 0.5 wt% in terms of CuO and Zr is 0.05 wt% in terms of ZrO ₂ with respect to 100 parts by weight of the main component. ≦ ZrO a ₂ ≦ 0.5% by weight, there the Fe in the range of 0 wt% ≦ _Fe 2 _{O 3} ≦ 1.0% by weight calculated as _Fe 2 _{O 3,} a main component phase having a garnet structure , 8 At 0 ℃ above 950 ° C. temperature below a polycrystalline ceramic magnetic material, characterized by sintering.

  The temperature characteristics of the sintering temperature, the ferromagnetic resonance half width ΔH, the dielectric loss tan δ, the saturation magnetization 4πMs, the saturation magnetization 4πMs are greatly influenced by the main component composition of the polycrystalline ceramic magnetic material. If the composition falls outside the composition range of the invention, the following problems occur.

Bi contributes to low temperature sintering. When x is x <0.5, the formation of heterogeneous phases is suppressed, but sintering at less than 950 ° C. becomes difficult. Further, when x> 0.9, sintering at 860 ° C. or more and less than 950 ° C. is possible, but a heterogeneous phase is likely to occur in the sintered body, and dielectric loss tan δ is tan δ> 10 × 10 ⁻⁴ and ferromagnetic resonance. The half-value width ΔH is remarkably increased as ΔH> 8000 (A / m). For this reason, x is preferably 0.5 ≦ x ≦ 0.9. Preferably, 0.55 ≦ x ≦ 0.75.

  Ca is added together with V described later, and contributes to preventing the low melting point V from evaporating during sintering. In order to exhibit such an effect, y is preferably set to 0.5 ≦ y ≦ 0.9.

Gd contributes to the adjustment of the temperature coefficient αm of the saturation magnetization 4πMs. If z exceeds 0.4, the temperature coefficient αm of saturation magnetization 4πMs from −20 to 60 ° C. may be αm <−0.21 (% / ° C.), and the temperature characteristics with the permanent magnet It cannot be compensated. Further, the dielectric loss tan δ is remarkably increased as tan δ ≧ 10 × 10 ⁻⁴ and the ferromagnetic resonance half width ΔH is ΔH> 8000 (A / m). For this reason, z is preferably 0 ≦ z ≦ 0.4.

In, Al, and V contribute to the adjustment of the temperature coefficient αm of the saturation magnetization 4πMs and the low-temperature sintering. The values of α, β, and γ are preferably set in the ranges of 0.05 ≦ α ≦ 0.4, 0 ≦ β ≦ 0.45, and 0.25 ≦ γ ≦ 0.45, respectively. When In, Al, and V are less than the above ranges, sintering at less than 950 ° C. becomes difficult. If the amount is less than the above range, the saturation magnetization 4πMs becomes 4πMs> 110 (mT), and the magnetic force of the permanent magnet having a predetermined shape is insufficient. Further, the dielectric loss tan δ is remarkably increased as tan δ ≧ 10 × 10 ⁻⁴ and the ferromagnetic resonance half width ΔH is ΔH> 8000 (A / m). In many cases, the saturation magnetization 4πMs is 4πMs <70 (mT), and the temperature characteristics with the permanent magnet cannot be compensated.

  Further, the subcomponent in the polycrystalline ceramic magnetic material of the present invention contributes to the suppression of heterogeneous phase and low temperature sintering, but the following problems occur when the composition is out of the composition range of the present invention.

First, when CuO is larger than 0.5% by weight with respect to the main component, sintering at low temperature becomes possible, but dielectric loss tan δ is tan δ ≧ 10 × 10 ⁻⁴ , and ferromagnetic resonance half width ΔH is ΔH. > 8000 (A / m). If it is 0% by weight, sintering at less than 950 ° C. becomes difficult. For this reason, it is desirable that CuO is 0.1 wt% ≦ CuO ≦ 0.5 wt% with respect to the main component. Preferably, 0.2 wt% ≦ CuO ≦ 0.4 wt%.

Further, ZrO ₂ is larger than 0.50 wt% with respect to the main component, prone to different phase in the sintered body ferromagnetic resonance half-width [Delta] H is significantly larger and ΔH> 8000 (A / m) . When the content is 0% by weight, the dielectric loss tan δ increases as tan δ ≧ 10 × 10 ⁻⁴ , and the ferromagnetic resonance half width ΔH increases as ΔH> 8000 (A / m). For this reason, it is desirable that ZrO ₂ is 0.05 wt% ≦ ZrO ₂ ≦ 0.50 wt% with respect to the main component. Preferably, 0.07 wt% ≦ ZrO ₂ ≦ 0.20 wt%.

On the other hand, if Fe ₂ O ₃ is larger than 1.0% by weight with respect to the main component, sintering at a low temperature becomes possible, but the ferromagnetic resonance half width ΔH becomes remarkably large as ΔH> 8000 (A / m). . Further, although the generation of a heterogeneous phase due to Bi at the yttrium (Y) site is suppressed, the heterogeneous phase at the iron (Fe) site is likely to occur, and ΔH> 8000 (A / m) is significantly increased.

With the above component composition, sintering can be performed at a low temperature of 860 ° C. or more and 950 ° C. or less, the saturation magnetization 4πMs is 70 mT to 110 mT, and the temperature coefficient αm is −0.35% / ° C. to −0.21. % / ° C., and a polycrystalline ceramic magnetic material having a ferromagnetic resonance half width ΔH of 8000 A / m or less can be obtained.
Therefore, the polycrystalline ceramic magnetic material of the present invention can be integrally sintered using a metal material having a high conductivity such as silver or copper as an internal electrode. Therefore, it is possible to suppress a loss due to the high Q value of the magnetic material and the electric resistance of the internal electrode, and to construct a microwave magnetic body with extremely small loss. As a result, it can be applied to microwave nonreciprocal circuit elements such as isolators and circulators to achieve excellent microwave characteristics and low loss.

Hereinafter, examples will be described in detail.
Starting materials of gadolinium oxide (Gd ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), calcium carbonate (CaCO ₃ ), bismuth oxide (Bi ₂ O ₃ ), iron oxide (Fe ₂ O) having a purity of 99.0% or more ₃ ), indium oxide (In ₂ O ₃ ), vanadium oxide (V ₂ O ₅ ), and aluminum oxide (Al ₂ O ₃ ) were prepared and weighed so that the composition ratios shown in Table 1 were obtained, and the slurry concentration Ion exchange water was added so that it might become 40%, and it wet-mixed with the ball mill for 25 to 45 hours, and dried after that. The dried powder was calcined by holding at a temperature of 800 ° C. to 875 ° C. for 1.5 hours to 2 hours. In addition, calcination is set to 40 to 70 degreeC low temperature rather than the sintering temperature in the sintering process which is a post process.

Next, copper oxide (CuO), zirconium oxide (ZrO ₂ ), and iron oxide (Fe ₂ O ₃ ) are prepared as subcomponents, and these are shown in Table 1 for the base material powder obtained as described above. Weighed and added to the composition ratio shown, added ion-exchanged water to a slurry concentration of 40%, wet crushed with a ball mill for 20 to 30 hours, and then dried to obtain a magnetic ceramic composition. The average particle size of the powder obtained as described above was adjusted to 0.25 μm to 1.5 μm. Even when the auxiliary component was added at the time of weighing the main component, the same effect was obtained.

Then, the granulated powder obtained by adding and kneading a binder solution in the magnetic ceramic composition obtained as described above, the molded body under pressure at a pressure from 1 ton / cm ² of 2 ton / cm ² did. This was fired in air at the firing temperature shown in Table 1 for 5 hours to obtain a sintered body.

  Next, a dielectric cylindrical resonator was fabricated using the obtained sintered body, and dielectric loss tan δ was measured by the Hack-Coleman method. Moreover, the saturation magnetization Ms of the sample for evaluation was measured using a vibration type magnetometer. Further, the obtained sintered body was processed into a thin disc shape with a thickness of 0.15 mm to 0.25 mm, and the ferromagnetic resonance half width ΔH was measured by a short-circuited coaxial line method. The results are shown in Table 1. The firing temperature is a temperature at which the sintered body is densified, and is a temperature at which the sintered body density does not substantially change with respect to the firing temperature in the relationship between the sintered body density and the firing temperature.

The asterisks shown in Table 1 are comparative examples outside the scope of the invention, and all other examples are examples within the scope of the invention. As shown in Table 1, Sample No. In Example 1, the generation of heterogeneous phases was suppressed, but out of the range of 0.5 ≦ x ≦ 0.90, so that a dense sintered body could not be obtained at a firing temperature of less than 950 ° C. Sample No. In 2, 3, and 4, the subcomponents Cu, Zr and Fe are each 0.1% by weight ≦ CuO ≦ 0.5% by weight in terms of CuO and Zr is 0.05% by weight ≦ ZrO in terms of ZrO _{2. 2} ≦ 0.5 wt%, 0 wt% of Fe in terms _{of Fe} 2 _{O 3} <to deviate from _Fe 2 _{O 3} ≦ 1.0 wt% range, different phase by Bi yttrium (Y) sites is generated, The dielectric loss tan δ exceeded 10 × 10 ⁻⁴ and the magnetic resonance half width ΔH exceeded 8000 A / m. Sample No. In 8, 12 to a by-component Fe is out of 0 wt% ≦ _Fe 2 _{O 3} ≦ 1.0% by weight in the range in terms _{of Fe} 2 _{O 3,} heterogeneous phase occurs in the iron (Fe) site, magnetic The resonance half width ΔH exceeded 8000 A / m.

In the examples within the scope of the present invention, a dense sintered body can be obtained at a temperature of 860 ° C. or more and less than 950 ° C., and the dielectric loss tan δ is tan δ ≦ 10 × 10 ⁻⁴ and the ferromagnetic resonance half width. ΔH is ΔH <8000 (A / m). Further, the temperature coefficient αm of the saturation magnetization 4πMs from −20 to 60 ° C. becomes −0.35% / ° C. to −0.21% / ° C., and the temperature characteristics with the permanent magnet can be compensated. Further, the addition of 0% by weight <Fe ₂ O ₃ ≦ 1.0% by weight in terms of Fe ₂ O ₃ as an accessory component suppresses the generation of a heterogeneous phase due to Bi at the yttrium (Y) site.

A microwave magnetic material made of a polycrystalline ceramic magnetic material according to the present invention and a nonreciprocal circuit device using the same will be described. FIG. 1 is a perspective view showing the appearance of a microwave magnetic body (central conductor assembly) used in one embodiment of the present invention. FIG. 2 is an exploded perspective view of the central conductor assembly, and FIG. 3 is an exploded perspective view of a non-reciprocal circuit device according to an embodiment of the present invention.
As the basic configuration of the nonreciprocal circuit element, a central conductor assembly 4, a capacitor multilayer body 5 in which the central conductor assembly 4 is incorporated in a central through hole, and the capacitor multilayer body 5 are incorporated. A resistor 90 formed of a chip or a resistive film, a permanent magnet 3 for applying a DC magnetic field to the central conductor assembly 4, and a metal upper case 1 that also serves as a magnetic yoke, as well as a lower case 2. Between the capacitor multilayer body 5 and the lower case 2, a resin base 6 having a connection terminal to the mounting substrate and a connection electrode for connecting the central conductor assembly 4 and the capacitor multilayer body 5 is disposed.

The central conductor assembly 4 is formed by laminating and arranging a central conductor on a rectangular microwave magnetic body having first and second main surfaces facing each other and side surfaces connecting the main surfaces.
The manufacturing process of the central conductor assembly 4 is as follows. First, Bi ₂ O ₃ , Y ₂ O ₃ , CaCO ₃ , Fe ₂ O ₃ , In ₂ O ₃ , V ₂ O ₅ are used as starting materials, and the main component is represented by the general formula (Y _1.53 Bi _0.65 Ca _{0 .82} ) (Fe _4.03 In _0.26 Al _0.30 V _0.41 ) O ₁₂ (atomic%) (Sample No. 9) and weighed the starting materials in a ball mill. The obtained slurry was dried, calcined at a temperature of 850 ° C., and wet pulverized with a ball mill.
Next, copper oxide (CuO), zirconium oxide (ZrO ₂ ), and iron oxide (Fe ₂ O ₃ ) were prepared as subcomponents, and CuO 0 with respect to 100 parts by weight of the base material powder obtained as described above. .20 _wt%, ZrO 2 0.10 _{wt%, Fe} 2 O 3 0.30 were weighed in a weight% was added, the ion-exchanged water so that the slurry concentration of 40% was added, the 20 ball mill 30 Wet milled for a period of time and then dried to obtain a polycrystalline ceramic magnetic material. The average particle size of the powder obtained as described above was adjusted to 0.25 μm to 1.5 μm.
The magnetic material powder, an organic binder, a plasticizer, and an organic solvent were mixed by a ball mill to adjust the viscosity, and then a magnetic ceramic green sheet having a thickness of 40 μm to 150 μm was prepared by a doctor blade method.

  Via holes of φ0.1 to φ0.4 (indicated by black circles in the figure) are formed by laser processing on the obtained ceramic green sheet, and a conductive paste serving as a central conductor is printed, and the green sheets are further stacked. After heating to 80 ° C. and thermocompression bonding at a pressure of 12 MPa to form a laminate, after cutting the laminate with, for example, a dicing saw or steel blade so as to have a predetermined size and shape, at 920 ° C., Baked for 8 hours. The via hole is filled with an Ag conductor, and the center conductors 44a to 44c are connected to the ground electrode Gnd and the input / output electrodes In, Out, and Load. In this way, the central conductors 44a to 44c cross each other at an equal angle while keeping insulation from each other, and the ground electrode GND and the input / output electrodes In, Out, and Load are provided as an LGA (Land Grid Array) on the second main surface 43f. A central conductor assembly 4 was obtained.

  The capacitor laminate 5 has an input capacitance electrode C1, an output capacitance electrode C2, a load capacitance electrode C3 for forming a matching capacitance, and a ground electrode Gnd on which a termination resistor 90 is disposed on the upper surface and inside the laminate. Has been. In addition, input / output electrodes In, Out, Load, and a ground electrode Gnd for electrical connection to the resin base 6 are provided on the back surface of the capacitor laminate 5.

  The resin base 6 is manufactured by, for example, using a copper plate having a thickness of 0.1 mm and integrally molding the copper plate and the liquid crystal polymer by injection molding. On the upper surface of the resin base 6, that is, on the connection surface side with the capacitor laminate 5, connection electrodes In, Out, Load, and GND are formed of a conductor plate, and are configured in a planar shape including the resin portion. In addition, the connection electrodes In, Out, Load, GND are formed on the same plane, the connection electrodes GND, Load and the terminal G, and the connection electrodes In, Out are configured by the same conductor plate, respectively, as the terminal electrodes P1, P2. Electrically connected.

  As the permanent magnet, a La-Co substituted ferrite magnet YBM-9BE manufactured by Hitachi Metals, Ltd., which was formed in a square shape was used. This permanent magnet has a residual magnetic flux of 430 mT to 450 mT and a temperature coefficient of the residual magnetic flux density of −0.20% to −0.18%. About the shape of the permanent magnet. Arbitrary shapes such as a disk shape and a hexagonal shape can be adopted. The same applies to the shape of the garnet.

  After the obtained center conductor assembly 4 is placed in the through hole of the capacitor multilayer body 5, it is connected via the connection electrode of the resin base 6, and the permanent magnet 3 is placed on the upper side of the center conductor assembly 4. Was covered with an upper case 1 and a lower case 2 to form a nonreciprocal circuit device. The temperature characteristics of the non-reciprocal circuit element of the present invention were evaluated for the insertion loss. However, the non-reciprocal circuit element having excellent temperature characteristics was obtained with a small variation in frequency at which the insertion loss accompanying temperature change was minimized.

  According to the present invention, firing can be performed at a low temperature of 860 ° C. or more and less than 950 ° C., and simultaneous firing with a low-resistance metal material such as silver or copper is possible. A polycrystalline ceramic magnetic material having a small resonance half width ΔH and dielectric loss tan δ, a microwave magnetic material, and a nonreciprocal circuit device using the same can be provided. As a result, it can be applied to microwave nonreciprocal circuit elements such as circulators and isolators to realize excellent microwave characteristics and low loss.

It is a perspective view which shows the external appearance of the microwave magnetic body (center conductor assembly) of the nonreciprocal circuit device based on one Example of this invention. It is a disassembled perspective view of the microwave magnetic body (center conductor assembly) of the nonreciprocal circuit device based on one Example of this invention. 1 is an exploded perspective view of a non-reciprocal circuit device according to one embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Upper case 2 Lower case 3 Permanent magnet 4 Center conductor assembly 5 Capacitor laminated body 6 Resin bases 44a-44c Center conductor

Claims (5)

Main component, the general formula _{(Y 3.0-x-y-} z Bi x Ca y Gd z) (Fe 5-α-β-γ In α Al β V γ) has a composition represented by _{O 12} ,
the values of x, y, z are 0.5 ≦ x ≦ 0.9, 0.5 ≦ y ≦ 0.9, 0 ≦ z ≦ 0.4,
The values of α, β, and γ are in the range of 0.05 ≦ α ≦ 0.4, 0 ≦ β ≦ 0.45, 0.25 ≦ γ ≦ 0.45, and Cu and Zr as subcomponents Fe is included, and the content thereof is 0.1 wt% ≦ CuO ≦ 0.5 wt% in terms of CuO, and 0.05 wt% ≦ Zr in terms of ZrO ₂ with respect to 100 parts by weight of the main component. polycrystalline ceramic magnetic material, characterized in that ZrO ₂ ≦ 0.5 wt%, 0 wt% of Fe in terms _{of Fe} 2 _{O 3 <Fe} 2 _{O 3} ≦ 1.0% by weight.   The saturation magnetization 4πMs is 70 mT to 110 mT, the temperature coefficient αm is −0.35% / ° C. to −0.21% / ° C., and the ferromagnetic resonance half width ΔH is less than 8000 A / m. The polycrystalline ceramic magnetic material according to claim 1.   A microwave magnetic body obtained by integrally sintering the polycrystalline ceramic magnetic material according to claim 1 and a conductor paste containing any one of Ag, Cu, an Ag alloy, and a Cu alloy, A microwave magnetic body comprising an electrode pattern formed of the conductive paste inside and / or on the surface of a wave magnetic body.   An electrode pattern formed on the microwave magnetic body according to claim 3 is used as a central conductor, and a capacitor connected to the central conductor and a ferrite magnet that applies a DC magnetic field to the microwave magnetic body are provided. Non-reciprocal circuit element.   The nonreciprocal circuit according to claim 4, wherein the ferrite magnet has a residual magnetic flux density Br of 420 mT or more and a temperature coefficient of -0.15% / ° C to -0.25% / ° C. element.

Images