CN110372383B - high-Q temperature-stable microwave dielectric ceramic material and preparation method and application thereof - Google Patents
high-Q temperature-stable microwave dielectric ceramic material and preparation method and application thereof Download PDFInfo
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- CN110372383B CN110372383B CN201910640452.9A CN201910640452A CN110372383B CN 110372383 B CN110372383 B CN 110372383B CN 201910640452 A CN201910640452 A CN 201910640452A CN 110372383 B CN110372383 B CN 110372383B
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Abstract
The invention discloses a high-Q temperature-stable microwave dielectric ceramic material, a preparation method and application thereof, wherein the chemical formula of the high-Q temperature-stable microwave dielectric ceramic material is CexY1‑xO1.5+x/2(x is 0.5, 0.75), wherein x is the molar doping amount of Y. The microwave dielectric ceramic prepared by the solid-phase reaction method has the sintering temperature of 1400-1550 ℃ and the density of 5.652-6.054 g/cm3The dielectric constant is 19.25 to 20.46, the quality factor is 65600 to 149290GHz, and the temperature coefficient of the resonance frequency is-29.8 to-13.52 ppm/DEG C. The element made of the microwave dielectric ceramic not only has more stable performance and service life, but also has stronger thermal stability so as to reduce the propagation error of signals. Meanwhile, the preparation process is reliable in flow, simple to operate, high in fault tolerance rate, suitable for industrial production and high in practical application value.
Description
Technical Field
The invention relates to a ceramic material and a preparation method thereof, in particular to a high-Q temperature-stable microwave dielectric ceramic material, a preparation method and application thereof, which are applied to the fields of electronic information materials and components.
Background
The microwave dielectric material is a novel information functional material developed in the beginning of the 20 th century and the 80 th century based on a microwave communication technology, and is one of the research hotspots in the field of domestic and foreign electronic functional materials. The performance of a microwave dielectric material is generally evaluated in terms of dielectric constant (. epsilon.r), quality factor (Q.times.f) (where f is the resonance frequency and Q is the inverse of the loss tangent), and temperature coefficient of resonance frequency (. tau.f). The quality factor directly affects the quality and energy loss of the microwave component, thereby affecting the performance stability and service life of the component. The temperature coefficient of the resonant frequency is a parameter reflecting the thermal stability of the microwave device, and restricts the practicability of the microwave dielectric material.
With the coming of the 5G communication era, the communication frequency is continuously improved, and the development of microwave dielectric materials is facing the challenges of the design of a new high-Q-value system and the Q-value optimization of the existing materials. In the microwave dielectric ceramic in the prior art, the case of stable temperature is not lacked, but the quality factor is lower, and higher use requirements cannot be met.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide a high-Q temperature-stable microwave dielectric ceramic material, and a preparation method and application thereof.
In order to achieve the purpose, the invention adopts the technical scheme that: a high Q temperature stable microwave dielectric ceramic material with a chemical formula of Ce, and its preparation method and applicationxY1-xO1.5+x/2(x is 0.5, 0.75), wherein x is the molar doping amount of Y.
The invention also provides a preparation method of the high-Q temperature stable microwave dielectric ceramic material, which comprises the following steps:
(1) chemical raw material CeO2、Y2O3In stoichiometric formula CexY1-xO1.5+x/2Weighing the ingredients (x is 0.5, 0.75);
(2) mixing the chemical raw materials prepared in the step (1), adding absolute ethyl alcohol as a ball milling medium, and performing ball milling for 6 hours;
(3) putting the raw materials subjected to ball milling in the step (2) into a drying oven, drying at 100 ℃, and sieving the dried powder with a 40-mesh sieve;
(4) placing the powder obtained after sieving in the step (3) into a crucible, and calcining for 4 hours at 1400 ℃;
(5) putting the calcined powder obtained in the step (4) into a ball mill, adding absolute ethyl alcohol as a ball milling medium, and carrying out ball milling for 24 hours;
(6) putting the raw materials subjected to ball milling in the step (5) into a drying oven, drying at 100 ℃, and sieving the dried powder with a 40-mesh sieve;
(7) adding paraffin wax into the dried powder in the step (6), placing the powder on a resistance furnace, uniformly stir-frying, and sieving by a 80-mesh sieve;
(8) pressing the powder sieved in the step (7) into a blank by using a powder tablet press;
(9) and (4) sintering the blank obtained in the step (8) at 1400-1550 ℃, and preserving heat for 4 hours to prepare the microwave dielectric ceramic with high quality factor and stable temperature.
Preferably, in the step (2), the ratio of raw materials in the ball milling tank: anhydrous ethanol: the mass ratio of the zirconium balls is 1: 1: 1.5; in the step (5), the powder in the ball milling tank is: anhydrous ethanol: the mass ratio of the zirconium balls is 1: 1: 1.5.
preferably, the weight of the paraffin wax added in the step (7) accounts for 8-10% of the total weight of the substance.
Preferably, the blank obtained in step (8) is cylindrical and has the following dimensions: the diameter d is 10mm and the height h is 5 mm.
By using the Ce provided by the inventionxY1-xO1.5+x/2And (x ═ 0.5, 0.75) can be used for manufacturing microwave elements, where x is the molar doping amount of Y.
Ce provided by the inventionxY1-xO1.5+x/2(x is 0.5, 0.75) the ceramic sample has a high quality factor (can reach 149290GHz), and the resonant frequency temperature is within +/-30 ppm/DEG C, so that the ceramic sample belongs to high-Q-value temperature-stable microwave dielectric ceramic; the element made of the microwave dielectric ceramic not only has more stable performance and service life, but also has stronger thermal stability so as to reduce signal propagation errors. The ceramic material of the invention can be prepared by a conventional solid-phase reaction method, and the preparation process flow thereofThe method has the advantages of reliable process, simple operation, high fault tolerance rate, suitability for industrial production and high practical application value.
Drawings
FIG. 1 shows Ce prepared according to the technical scheme of embodiment 1 of the invention0.5Y0.5O1.75An X-ray diffraction pattern of the ceramic sample;
FIG. 2 shows Ce prepared according to the technical scheme of the embodiment 1 of the invention0.5Y0.5O1.75Scanning electron microscope atlas of the ceramic sample;
FIG. 3 shows Ce prepared according to the technical scheme of example 6 of the invention0.75Y0.25O1.875An X-ray diffraction pattern of the ceramic sample;
FIG. 4 shows Ce prepared according to the technical scheme of the embodiment 6 of the invention0.75Y0.25O1.875Scanning electron microscopy of ceramic samples.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Example 1
According to the chemical formula Ce0.5Y0.5O1.75The stoichiometric ratio of each element in the alloy is determined by weighing CeO2(analytical grade), Y2O3(analytical pure) chemical reagents; putting the weighed powder into a ball milling tank, and ball milling and mixing for 6 hours by taking absolute ethyl alcohol as a ball milling medium; drying and sieving the ball-milled raw materials, putting the raw materials into an alumina crucible, and heating the raw materials to 1400 ℃ by using a muffle furnace to calcine the raw materials for 4 hours; ball-milling the calcined powder for 24 hours again, drying, sieving, adding paraffin, frying uniformly, and sieving with a 80-mesh sieve; pouring a proper amount of powder into a die, and preparing a cylindrical sample with the diameter of 10mm multiplied by 5mm under the pressure of 200MPa by using a powder tablet press; finally, the sample is put into a high-temperature box type furnace for sintering, the sintering temperature is 1450 ℃, the heating rate is 5 ℃/min, the heat preservation is carried out for 4 hours, and the Ce is prepared0.5Y0.5O1.75Microwave dielectric ceramics.
Referring to the attached FIG. 1, Ce prepared according to the technical scheme of the embodiment0.5Y0.5O1.75X-ray diffraction pattern of ceramic sampleThe spectrum, as can be seen from the figure, the ceramics produced had a single phase, which was retrieved as CeO2And (4) phase(s). The X-ray diffraction pattern shows that Y ions enter CeO after being doped2In the crystal lattice, the Ce site is occupied, and a solid solution is formed.
Referring to the attached FIG. 2, the Ce prepared according to the technical scheme of the embodiment0.5Y0.5O1.75The scanning electron microscope atlas of the ceramic sample can show that the surface of the prepared ceramic sample has no obvious air holes and straight grain boundary, which indicates that the sample is sintered compactly.
The density of the material prepared by the method is 5.952g/cm3Dielectric constant of 19.27, quality factor Qxf 128800GHz, temperature coefficient of resonance frequency tauf＝-29.8ppm/℃。
Examples 2-5 were prepared similarly to example 1, except for the sintering temperature. Table 1 shows the sintering temperatures and the corresponding material densities and microwave dielectric properties for each example.
TABLE 1 sintering temperatures, densities and microwave dielectric properties of examples 1-5, ceramic samples produced
Referring to the attached FIG. 2, the Ce prepared according to the technical scheme of the embodiment0.5Y0.5O1.75The scanning electron microscope atlas of the ceramic sample can show that the surface of the prepared ceramic sample has no obvious air holes and straight grain boundary, which indicates that the sample is sintered compactly.
Example 6
According to the chemical formula Ce0.75Y0.25O1.875The stoichiometric ratio of each element in the alloy is determined by weighing CeO2(analytical grade), Y2O3(analytical pure) chemical reagents; putting the weighed powder into a ball milling tank, and ball milling and mixing for 6 hours by taking absolute ethyl alcohol as a ball milling medium; drying and sieving the ball-milled raw materials, putting the raw materials into an alumina crucible, and heating the raw materials to 1400 ℃ by using a muffle furnace to calcine the raw materials for 4 hours; the calcined powder is ball milled for 24 hours again,drying, sieving, adding paraffin, parching, and sieving with 80 mesh sieve; pouring a proper amount of powder into a die, and preparing a cylindrical sample with the diameter of 10mm multiplied by 5mm under the pressure of 200MPa by using a powder tablet press; finally, the sample is put into a high-temperature box type furnace for sintering, the sintering temperature is 1400 ℃, the heating rate is 5 ℃/min, the heat preservation is carried out for 4 hours, and the Ce is prepared0.75Y0.25O1.875Microwave dielectric ceramics.
Referring to the attached FIG. 3, the Ce prepared according to the technical scheme of the embodiment0.75Y0.25O1.875The X-ray diffraction pattern of the ceramic sample shows that the prepared ceramic has a single phase, and is retrieved as CeO2And (4) phase(s). The X-ray diffraction pattern shows that Y ions enter CeO after being doped2In the crystal lattice, the Ce site is occupied, and a solid solution is formed.
Referring to FIG. 4, Ce is prepared according to the technical scheme of the embodiment0.75Y0.25O1.875The scanning electron microscope atlas of the ceramic sample can show that the surface of the prepared ceramic sample has no obvious pores and the sample is sintered compactly; but the grain size distribution on the surface of the sample was not uniform.
The density of the material prepared by the method is 5.959g/cm3Dielectric constant of 19.78, quality factor Qxf 65600GHz, temperature coefficient of resonance frequency tauf＝-17.73ppm/℃。
The preparation of examples 7-10 is similar to example 6, except for the sintering temperature. Table 2 shows the sintering temperatures and the corresponding material densities and microwave dielectric properties for each example.
TABLE 2 sintering temperatures, densities and microwave dielectric properties of examples 6-10, ceramic samples produced
Claims (5)
1. The preparation method of the high-Q temperature-stable microwave dielectric ceramic material is characterized by comprising the following steps of:
(1) will be provided withChemical raw material CeO2、Y2O3In stoichiometric formula CexY1-xO1.5+x/2(x ═ 0.5 or 0.75) weigh the ingredients;
(2) mixing the chemical raw materials prepared in the step (1), adding absolute ethyl alcohol as a ball milling medium, and performing ball milling for 6 hours;
(3) putting the raw materials subjected to ball milling in the step (2) into a drying oven, drying at 100 ℃, and sieving the dried powder with a 40-mesh sieve;
(4) placing the powder obtained after sieving in the step (3) into a crucible, and calcining for 4 hours at 1400 ℃;
(5) putting the calcined powder obtained in the step (4) into a ball mill, adding absolute ethyl alcohol as a ball milling medium, and carrying out ball milling for 24 hours;
(6) putting the raw materials subjected to ball milling in the step (5) into a drying oven, drying at 100 ℃, and sieving the dried powder with a 40-mesh sieve;
(7) adding paraffin wax into the dried powder in the step (6), placing the powder on a resistance furnace, uniformly stir-frying, and sieving by a 80-mesh sieve;
(8) pressing the powder sieved in the step (7) into a blank by using a powder tablet press;
(9) and (4) sintering the blank obtained in the step (8) at 1400-1550 ℃, and preserving heat for 4 hours to prepare the microwave dielectric ceramic.
2. The method for preparing a high-Q temperature stable microwave dielectric ceramic material according to claim 1, wherein in the step (2), the raw materials in the ball mill pot: anhydrous ethanol: the mass ratio of the zirconium balls is 1: 1: 1.5; in the step (5), the powder in the ball milling tank is: anhydrous ethanol: the mass ratio of the zirconium balls is 1: 1: 1.5.
3. the method for preparing a high-Q temperature-stable microwave dielectric ceramic material as claimed in claim 1, wherein the weight of the paraffin wax added in the step (7) is 8-10% of the total weight of the material.
4. The method for preparing a high-Q temperature stable microwave dielectric ceramic material according to claim 1, wherein the green body obtained in step (8) is cylindrical and has the following dimensions: the diameter d is 10mm and the height h is 5 mm.
5. The application of the high-Q temperature stable microwave dielectric ceramic material is characterized in that Ce is utilizedxY1-xO1.5+x/2(x is 0.5 or 0.75) a microwave element was produced, wherein x is the molar doping amount of Ce.
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| US9440886B2 (en) * | 2013-11-12 | 2016-09-13 | Applied Materials, Inc. | Rare-earth oxide based monolithic chamber material |
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| CN102153342A (en) * | 2010-12-27 | 2011-08-17 | 南京工业大学 | Composite doped modified Y2Ti2O7 microwave medium ceramic material |
| US9353012B2 (en) * | 2013-03-15 | 2016-05-31 | Amedica Corporation | Charge-compensating dopant stabilized alumina-zirconia ceramic materials and related materials, apparatus, and methods |
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