阅读说明：本技术 一种微波介质烧结粉体材料的制备方法、微波介质陶瓷及其应用 (Preparation method of microwave dielectric sintered powder material, microwave dielectric ceramic and application thereof ) 是由 聂敏 刘剑 彭虎 于 2019-11-13 设计创作，主要内容包括：本发明提供一种微波介质烧结粉体材料的制备方法、微波介质陶瓷及其应用,方法包括：制备主粉体xMgO-(1-x)TiO<Sub>2</Sub>,x为MgO的摩尔分数比,0.475≤x≤0.495；将主粉体xMgO-(1-x)TiO<Sub>2</Sub>和改性剂CaCO<Sub>3</Sub>、ZnO、ZrO<Sub>2</Sub>、Mn<Sub>3</Sub>O<Sub>4</Sub>、SiO<Sub>2</Sub>混合得到混合物；加水后球磨粉碎并干燥得到微波介质烧结粉体材料；改性剂CaCO<Sub>3</Sub>、ZnO、ZrO<Sub>2</Sub>、Mn<Sub>3</Sub>O<Sub>4</Sub>、SiO<Sub>2</Sub>占所述主粉体xMgO-(1-x)TiO<Sub>2</Sub>的质量百分比分别为1.7％～5.89％、0.05％～2％、0.05％～1％、0.05％～1％、0.05％～1％。制备工艺简单,无污染,所得的微波介质陶瓷致密,满足微波器件的应用。(The invention provides a preparation method of a microwave dielectric sintered powder material, microwave dielectric ceramic and application thereof, wherein the method comprises the following steps: preparation of Main powder xMgO- (1-x) TiO 2 X is the mole fraction ratio of MgO, and x is more than or equal to 0.475 and less than or equal to 0.495; mixing main powder xMgO- (1-x) TiO 2 And modifier CaCO 3 、ZnO、ZrO 2 、Mn 3 O 4 、SiO 2 Mixing to obtain a mixture; adding water, ball-milling, crushing and drying to obtain a microwave medium sintered powder material; modifier CaCO 3 、ZnO、ZrO 2 、Mn 3 O 4 、SiO 2 Occupying the main powder xMgO- (1-x) TiO 2 The mass percentages of the components are respectively 1.7-5.89%, 0.05-2%, 0.05-1% and 0.05-1%. The preparation process is simple, no pollution is caused, and the obtained microwave dielectric ceramic is compact and meets the application requirements of microwave devices.)

1. A preparation method of a microwave medium sintering powder material is characterized by comprising the following steps:

s1: preparation of Main powder xMgO- (1-x) TiO₂Wherein x is the mole fraction ratio of MgO, and x is more than or equal to 0.475 and less than or equal to 0.495;

s2: mixing the main powder xMgO- (1-x) TiO₂And modifier CaCO₃、ZnO、ZrO₂、Mn₃O₄、SiO₂Mixing to obtain a mixture;

s3: adding water into the mixture, ball-milling, crushing and drying to obtain a microwave medium sintered powder material;

wherein, the modifier CaCO₃、ZnO、ZrO₂、Mn₃O₄、SiO₂Occupying the main powder xMgO- (1-x) TiO₂The mass percentages of the components are respectively 1.7-5.89%, 0.05-2%, 0.05-1% and 0.05-1%.

2. The method for preparing microwave dielectric sintered powder material as claimed in claim 1, wherein the main powder xMgO- (1-x) TiO is prepared₂The method comprises the following steps: mixing MgO and TiO₂In a molar ratio x: 1-x mixing, adding water, ball-milling, crushing, drying and presintering to obtain the main powder xMgO- (1-x) TiO₂。

3. The method of claim 2, wherein the MgO and the TiO are mixed to form a sintered powder material₂Both being in the order of microns, the MgO and the TiO₂The particle size of the particles is between 1 and 20 mu m.

4. The method for preparing a microwave dielectric sintered powder material according to claim 2, wherein the pre-sintering is sintering at 1050 ℃ -1150 ℃ for 2-4 hours.

5. The method for preparing microwave dielectric sintered powder material as claimed in any one of claims 1 to 4, wherein the CaCO is used as a raw material₃The ZnO and the Mn₃O₄All on a nanometer scale, the CaCO₃The ZnO and the Mn₃O₄The particle size of (A) is between 100 and 200 nm.

6. The method for preparing microwave dielectric sintered powder material as claimed in any one of claims 1 to 4, wherein the drying is spray drying.

7. A microwave dielectric ceramic material is characterized in that the microwave dielectric sintered powder material prepared by the preparation method of the microwave dielectric sintered powder material according to any one of claims 1 to 6 is used as a raw material, and is prepared by spraying, granulating, pressing, molding and sintering at 1320-1380 ℃ for 2-4 h.

8. The microwave dielectric ceramic material as claimed in claim 7, wherein the spray granulation is prepared by mixing and stirring the microwave dielectric sintered powder material, PVA aqueous solution, dispersant and defoamer uniformly, and spraying, wherein the dispersant is ammonium polyacrylate, and the defoamer is polydimethylsiloxane.

9. A microwave dielectric ceramic material as claimed in claim 8, wherein the spraying is carried out by a spray dryer, wherein the temperature of the air inlet of the spray dryer is 250 ℃ to 300 ℃, and the temperature of the air outlet of the spray dryer is 150 ℃ to 180 ℃.

10. Use of the microwave dielectric ceramic of any one of claims 7 to 9 in a microwave device comprising a circulator, an isolator, a filter.

Technical Field

The invention relates to the technical field of ceramic materials, in particular to a preparation method of a microwave dielectric sintered powder material, a microwave dielectric ceramic and application thereof.

Background

The microwave dielectric ceramic material is ceramic which is applied to a microwave frequency band circuit as a dielectric material and completes one or more functions, is widely used as a dielectric substrate, a resonator, a filter, a dielectric guided wave loop and other microwave components in modern communication, and is a key basic material of modern communication technology.

In the moving 2G and 3G times, the communication frequency is lower, and the circulator and the isolator meet the requirements by filling polyvinyl fluoride (the dielectric constant is about 2.5) on the peripheries of an upper microwave ferrite material and a lower microwave ferrite material. The popularization of current 4G, 5G times, communication frequency promotes greatly, in order to satisfy high frequency, low-loss, the stable requirement of temperature under the condition that reduces the volume, increases a microwave dielectric ceramic material at the periphery of microwave ferrite piece, can improve holistic dielectric constant, and then can reduce the size of circulator, isolator, satisfies the miniaturized requirement of device.

Chinese patent with application number 201410097205.6 discloses MgTiO₃-SrTiO₃Microwave dielectric ceramic composite material made of MgTiO₃、SrTiO₃、Yb₂O₃、Y₂O₃And Sm₂O₃The composition has a dielectric constant of about 20. Chinese patent application No. 201410707197.2 discloses a microwave dielectric material, whose formula composition (including by weight percent) is 61-92% MgTiO₃、3-23％CaTiO₃、1-12％MgO、0.01-1.5％V₂O₅、0.01-1％CeO₂、0.5-2.5％La(Ti_1/2Mg_1/2)O₃、0.1-1.5％Bi₂TiSiO₇The dielectric constant of the microwave dielectric material is 20-22. Application number 201810793134.1Chinese patent discloses a method for preparing a magnesium-doped titanium dioxide (MgTiO)₃As a matrix, with Ca_0.5Sr_0.5TiO₃Or Ca_0.5Sr_0.5TiO₃And LnAlO₃A microwave dielectric material in which a mixture of (Ln ═ Pr, Nd, La, Sm) is used as an additive and which has a dielectric constant of about 20.

Magnesium metatitanate (MgTiO) having an ilmenite structure₃E 17, Q22000, τ_f(-55 ppm/° c) is an important microwave dielectric ceramic material because the raw material is relatively cheap and the microwave performance is excellent, but the frequency temperature coefficient is large, so that the practical application is adversely affected. In the above patent, rare earth elements such as Sr, Yb, Y, Sm, Ce, La, Pr, Nd and V, Bi are commonly used in microwave dielectric ceramic powder with a dielectric constant of about 20 to maintain its dielectric properties, which is not favorable for cost reduction (La (Ti) is used for ceramic powder_{1/ 2}Mg_1/2)O₃、Bi₂TiSiO₇、Ca_0.5Sr_0.5TiO₃The preparation process of such compounds is also complicated). Therefore, the prior art lacks a microwave dielectric ceramic with good microwave performance and low price.

Disclosure of Invention

The invention provides a preparation method of a microwave medium sintered powder material, a microwave medium ceramic and application thereof, aiming at solving the existing problems.

In order to solve the above problems, the technical solution adopted by the present invention is as follows:

a preparation method of a microwave medium sintering powder material comprises the following steps: s1: preparation of Main powder xMgO- (1-x) TiO₂Wherein x is the mole fraction ratio of MgO, and x is more than or equal to 0.475 and less than or equal to 0.495; s2: mixing the main powder xMgO- (1-x) TiO₂And modifier CaCO₃、ZnO、ZrO₂、Mn₃O₄、SiO₂Mixing to obtain a mixture; s3: adding water into the mixture, ball-milling, crushing and drying to obtain a microwave medium sintered powder material; wherein, the modifier CaCO₃、ZnO、ZrO₂、Mn₃O₄、SiO₂Occupying the main powder xMgO- (1-x) TiO₂In mass percent ofThe ratio is 1.7-5.89%, 0.05-2%, 0.05-1% and 0.05-1% respectively.

Preferably, the main powder xMgO- (1-x) TiO is prepared₂The method comprises the following steps: mixing MgO and TiO₂In a molar ratio x: 1-x mixing, adding water, ball-milling, crushing, drying and presintering to obtain the main powder xMgO- (1-x) TiO₂。

Preferably, the MgO and the TiO₂Both being in the order of microns, the MgO and the TiO₂The particle size of the particles is between 1 and 20 mu m.

Preferably, the pre-sintering is sintering at 1050-1150 ℃ for 2-4 hours.

Preferably, the CaCO₃The ZnO and the Mn₃O₄All on a nanometer scale, the CaCO₃The ZnO and the Mn₃O₄The particle size of (A) is between 100 and 200 nm.

Preferably, the drying is spray drying.

The invention also provides a microwave medium ceramic material which is prepared by taking the microwave medium sintered powder material prepared by the preparation method of the microwave medium sintered powder material as a raw material, performing spray granulation and compression molding, and sintering at 1320-1380 ℃ for 2-4 h.

Preferably, the spray granulation is prepared by mixing and stirring the microwave medium sintered powder material, a PVA aqueous solution, a dispersing agent and a defoaming agent uniformly, and spraying, wherein the dispersing agent is ammonium polyacrylate, and the defoaming agent is polydimethylsiloxane.

Preferably, spraying is carried out by a spray dryer, wherein the temperature of an air inlet of the spray dryer is 250-300 ℃, and the temperature of an air outlet of the spray dryer is 150-180 ℃.

The invention further provides the application of the microwave dielectric ceramic in a microwave device, wherein the microwave device comprises a circulator, an isolator and a filter.

The invention has the beneficial effects that: provides a preparation method of microwave medium sintered powder material, microwave medium ceramic and application thereof, which reasonably selects microwave mediumPreparing main powder and a modifier of a sintered powder material by an oxide method to obtain modified xMgO- (1-x) TiO with a dielectric constant of 18-23₂The microwave medium sintering powder material does not need atmosphere protection in the sintering process, the preparation process is simple, the environment cannot be polluted, the obtained microwave medium ceramic is compact, the microwave performance is excellent, the epsilon is 18-23, and the Q f value is 18-23>72000GHz，τ_fIs-1.5-0.5 ppm/DEG C, and can meet the application of microwave devices such as circulators, isolators and filters.

Drawings

FIG. 1 is a schematic diagram of a method for preparing a modified microwave dielectric sintered powder material according to an embodiment of the present invention.

FIG. 2 is a Scanning Electron Microscope (SEM) schematic view of the surface of a sintered sample of example 5 in an example of the present invention.

FIG. 3 is a schematic Scanning Electron Microscope (SEM) representation of the surface of the sintered sample of comparative example 4 in the example of the present invention.

FIG. 4 is a schematic Scanning Electron Microscope (SEM) representation of the surface of a sintered sample of comparative example 5 in an example of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the embodiments of the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. In addition, the connection may be for either a fixing function or a circuit connection function.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for convenience in describing the embodiments of the present invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be in any way limiting of the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.