Adjustable temperature drift dielectric microwave dielectric ceramic materials and their preparation methods

Abstract

This invention relates to the field of ceramic materials technology, specifically to a temperature-drift dielectric microwave dielectric ceramic material, the chemical composition of which is xCa 0.9 Sr 0.1 TiO3+(1-x)La (1‑y) Y y The AlO3 stoichiometric ratio is as follows: x = 0.6–0.7, y = 0–0.2. The microwave dielectric ceramic has a dielectric constant Er = 37–46, a quality factor Qf = 19500–26000 GHz, and a resonant frequency temperature coefficient τf = -24 ppm / ℃ to +7 ppm / ℃. This is achieved by changing the substitution amount of Y and Ca. 0.9 Sr 0.1 By adjusting the proportion of TiO3, a dielectric microwave dielectric ceramic material with a lower sintering temperature, a suitable dielectric constant, a lower dielectric loss, and a near-zero resonant frequency temperature coefficient can be obtained. Furthermore, while maintaining a relatively stable Qf value, the resonant frequency temperature coefficient and dielectric constant of this dielectric microwave dielectric ceramic material can be adjusted by gradient changes, which can better meet the different performance requirements of various microwave RF devices for materials.

Description

Technical Field

[0001] This invention relates to an adjustable temperature drift dielectric microwave dielectric ceramic material and its preparation method, belonging to the field of ceramic material technology. Background Technology

[0002] Microwave dielectric ceramics, as a novel electronic material, are frequently used in modern communications to fabricate resonators, filters, dielectric substrates, dielectric antennas, and dielectric waveguide circuits. They are widely applied in numerous fields of microwave technology, such as mobile phones, car phones, cordless phones, satellite television receivers, satellite broadcasting, radar, and radio remote control. With the continuous development of 5G technology, the requirements for materials are becoming increasingly stringent, and the application prospects of microwave dielectric ceramic materials will only continue to expand.

[0003] There are three main parameters for evaluating the dielectric properties of microwave dielectric ceramics in microwave circuits: relative permittivity Er, quality factor Q, and temperature coefficient of resonant frequency τf.

[0004] The tuning of dielectric constant and dielectric loss in microwave dielectric ceramic materials is now largely mature. Their key performance parameters mainly depend on their resonant frequency temperature coefficient, τf. The resonant frequency temperature coefficient represents the magnitude of the change in the resonant frequency of a resonator when temperature changes, and is used to measure the temperature stability of the resonant frequency. A larger τf indicates a greater drift in the device's center frequency with temperature changes, which will compromise the device's high stability in environments with varying temperatures.

[0005] CN201710794191.7 discloses a near-zero resonant frequency temperature coefficient microwave dielectric ceramic and its preparation method, which aims to adjust the temperature coefficient of Ba[(Co)]. 0.7 Zn 0.3 ) 1 / 3 Nb 2 / 3 The τf value of O3 is suitable for the near-zero τf requirement of microwave dielectric ceramics. Zn ion deficiency (Ba[(Co)) is employed. 0.7 Zn 0.28 ) 1 / 3 Nb 2 / 3 A method involving the addition of trace amounts of rare earth elements (CeO2, Y2O3) is used. A microwave dielectric ceramic material with a near-zero resonant frequency temperature coefficient is prepared via a simple solid-state method using BaCO3, CoO, ZnO, and Nb2O5 as raw materials. This preparation method requires a relatively large amount of rare earth elements, resulting in higher costs.

[0006] Therefore, inventing a low-cost microwave dielectric ceramic material with a resonant frequency temperature coefficient that can be adjusted in a gradient manner is of great significance and market value in practical use and production. Summary of the Invention

[0007] To address the aforementioned problems, this invention proposes a temperature-drift dielectric microwave ceramic material. By substituting La with appropriate Y doping, a microwave dielectric ceramic material with a lower sintering temperature, a suitable dielectric constant, lower dielectric loss, and an excellent resonant frequency temperature coefficient is obtained. Furthermore, the resonant frequency temperature can be adjusted in a gradient manner, which can well meet the performance requirements of microwave radio frequency devices.

[0008] The technical means adopted by this invention to solve the above problems is as follows: A temperature-driftable dielectric microwave dielectric ceramic material is disclosed, the chemical composition of which is xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 stoichiometric ratio is as follows: x = 0.6-0.7, y = 0-0.2.

[0009] In this adjustable temperature-drift dielectric microwave dielectric ceramic material, calcium carbonate, a common mineral with uniform particle size, excellent physical properties and chemical resistance, is used. It effectively improves the strength, hardness, and wear resistance of the ceramic. Calcium carbonate helps the product form a denser, more crystalline crystal structure, which is beneficial for improving the product's hardness and compressive strength. CaCO3 can form a high-resistivity layer at grain boundaries, increasing the resistivity of the grain boundaries and reducing eddy current losses. Simultaneously, calcium carbonate can also form a certain porosity in the product, thereby improving the insulation of the ceramic product. By providing uniform mineral particles, the uniformity and quality stability of the ceramic can be effectively guaranteed, thus improving the quality of the ceramic. Sr ions have a large ionic radius and low ionic charge, which can impart good electrical insulation properties (increasing resistance) and low dielectric loss to the ceramic body. TiO2 has excellent dielectric properties and can be used to manufacture high dielectric constant ceramic capacitors and microcrystalline active material titanate voltage-voltage ceramics. The role of TiO2 is to reduce lattice defects, prevent the formation of pores, and reduce stress near grain boundaries; therefore, the addition of TiO2 reduces material loss.

[0010] YAlO3 and LaAlO3 have the same perovskite structure and their dielectric losses are good and very similar. However, YAlO3 has a lower dielectric constant than LaAlO3 and a more negative temperature coefficient of resonant frequency. Combining the high dielectric constant and large positive temperature coefficient of CaTiO3 and SrTiO3, by replacing La with Y equivalent doping, increasing the proportion of CaTiO3 and SrTiO3, and by reasonably adjusting the relative content of doping substitution, a dielectric microwave dielectric ceramic material with a lower sintering temperature, a suitable dielectric constant, a lower dielectric loss, and an excellent temperature coefficient of resonant frequency can be obtained.

[0011] Furthermore, the microwave dielectric ceramic has a dielectric constant Er = 37-46, a quality factor Qf = 19500-26000 GHz, and a resonant frequency temperature coefficient τf = -24 ppm / ℃ to +7 ppm / ℃.

[0012] Another objective of this invention is to disclose a method for preparing the above-mentioned tunable temperature-drift dielectric microwave ceramic material, using calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y AlO3 was measured and mixed in the following order: calcium carbonate, strontium carbonate, and titanium dioxide were added sequentially to obtain mixture one; then lanthanum trioxide, yttrium trioxide, and aluminum oxide were mixed to obtain mixture two.

[0013] Furthermore, it includes the following steps:

[0014] S1. Mixture 1 and Mixture 2 are mixed together according to the metering ratio, a dispersant is added, and the mixture is ball-milled for 10-18 hours. The discharged material is sieved to obtain Mixed Oxide Slurry 1.

[0015] S2. Place the mixed oxide slurry obtained in step S1 in an oven at 120℃-180℃ and dry for 8h-12h, then pass it through a sieve to obtain mixed oxide powder.

[0016] S3. The mixed oxide powder obtained in step S2 is loaded into a corundum mullite sagger and placed in a box furnace for pre-firing for 3-6 hours at a pre-firing temperature of 1050-1200℃.

[0017] S4. Place the pre-calcined powder from step S3 into a ball mill, add the corresponding zirconium balls and pure water according to the ratio of raw material: zirconium balls: pure water = 1:2.0:1.2, add a small amount of dispersant and defoamer, grind in the ball mill for 10-18 hours, and then discharge and sieve to obtain mixed oxide slurry II.

[0018] S5. Place the mixed oxide slurry obtained in step S4 in an oven at 120℃-180℃ and dry for 8h-12h, then sieve to obtain mixed oxide powder.

[0019] S6. Add 8wt%-12wt% of PVA adhesive aqueous solution to the sieved mixed oxides, mix thoroughly, and then extrude, crush, and sieve to obtain a granulated mixture;

[0020] S7. Press the granulated powder into a green body; sinter it at a set temperature of 1380℃-1450℃ for 4h-8h to obtain the product.

[0021] Further, the raw materials of Mixture 1 are added according to the following ratio: Mixture 1: Grinding Media 1: Water = 1:1.5-3.0:1.0-1.5, for the first ball milling; the raw materials of Mixture 2 are added according to the following ratio: Mixture 2: Grinding Media 2: Water = 1:1.0-3.0:1.0-1.5, for the second ball milling. Grinding Media 1 and Grinding Media 2 can be zirconium balls. Two sizes of zirconium balls are used, with the smaller balls accounting for 3%-5% of the weight of the larger balls. This design, based on the characteristics of the raw materials, aims to minimize the diameter of the grinding media and increase the number of zirconium balls to increase the number of impacts on the material, thereby improving the grinding efficiency, while ensuring sufficient impact force.

[0022] Further, the dispersant in step S1 is ammonium polyacrylate, and the mass ratio of the amount of the dispersant added to the total amount of raw materials is 0.4-0.7:100.

[0023] Furthermore, the rotation speeds for the first ball milling, the second ball milling, and the grinding were all between 200 rpm and 300 rpm, with a total ball milling time of 10 h to 20 h and a grinding time of 10 h to 18 h.

[0024] Further, the dispersant and defoamer in step S4 are ammonium polyacrylate and tributyl phosphate, respectively, and the mass ratio of the amount of the dispersant and defoamer added to the total amount of raw materials is 0.4-0.7:100 and 0-0.4:100, respectively.

[0025] Further, the adhesive mentioned in step S4 is an 8%-12% PVA glue. Polyvinyl alcohol (PVA) increases the viscosity of the glue. After adding PVA to the glue, its molecular chains interact with other components in the glue to form a three-dimensional network structure. This structure increases the viscosity of the glue, making it more viscous when applied or coated, thus improving its adhesive properties. PVA has a certain promoting effect on the adhesive properties of the glue. The PVA molecular chains in the glue have a certain polarity and can interact with many material surfaces through hydrogen bonds or other chemical bonds, thereby enhancing the adhesion between the glue and the adhered materials. In this way, the glue can better adsorb onto the surface of the adhered materials during the bonding process, improving the bonding strength.

[0026] The beneficial effects of this invention are:

[0027] 1. The adjustable temperature drift dielectric microwave dielectric ceramic material of the present invention utilizes calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y yBy using AlO3 stoichiometric proportions and designing the raw material formulation, and by substituting La with appropriate Y doping, a microwave dielectric ceramic material with a low sintering temperature, suitable dielectric constant, low dielectric loss, excellent resonant frequency temperature coefficient, and adjustable resonant frequency temperature can be obtained. This material can well meet the performance requirements of microwave radio frequency devices.

[0028] 2. The sintering temperature of the adjustable temperature drift dielectric microwave dielectric ceramic material of the present invention is low: compared with the sintering temperature of 1450℃ in the same series, the present invention can be sintered well at about 1385℃, and obtains better dielectric performance parameters.

[0029] 3. The temperature coefficient of the resonant frequency of the adjustable temperature drift dielectric microwave dielectric ceramic material of the present invention can be adjusted by gradient change: the negative temperature coefficient Y can well compensate for the positive temperature coefficient of most materials to obtain the required 0 temperature coefficient, and the quality factor Qf value is relatively stable during adjustment without significant decrease. Detailed Implementation

[0030] The present invention will be further described below with reference to embodiments, but the scope of protection of the present invention is not limited thereto.

[0031] Density was measured using the water displacement method. The dielectric constant, quality factor, dielectric loss, and temperature coefficient of resonant frequency of the material were tested according to GB / T7265.2-1987 "Test Method for Microwave Complex Dielectric Constant of Solid Dielectrics - Open Cavity Method".

[0032] This adjustable temperature drift dielectric microwave dielectric ceramic material has a raw material chemical composition according to xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 stoichiometric ratio is as follows: x = 0.6-0.7, y = 0-0.2.

[0033] This invention utilizes calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 metering ratio is designed in the raw material formula. After the raw materials are distributed, they are ball-milled, dried and pre-fired; a binder is added to granulate and shape them, and finally sintered to prepare the product.

[0034] Examples 1-5

[0035] The method for preparing the adjustable temperature-drift dielectric microwave ceramic material in this embodiment uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr0.1 TiO3+(1-x)La (1-y) Y y The AlO3 is stoichiometrically prepared, where x = a1 (0.6 ≤ a1 ≤ 0.66), and y increases systematically, successively equal to 0.0, 0.05, 0.1, 0.15, and 0.2. During preparation, calcium carbonate, strontium carbonate, and titanium dioxide are added sequentially to obtain mixture one; then lanthanum trioxide, yttrium trioxide, and aluminum oxide are mixed to obtain mixture two.

[0036] S1. Mixture 1 and Mixture 2 are mixed together according to the metering ratio, a dispersant is added, and the mixture is ball-milled for 10-12 hours. The material is then discharged and sieved to obtain mixed oxide slurry 1. The dispersant in this step is ammonium polyacrylate, and the mass ratio of the amount of dispersant added to the total amount of raw materials is 0.4-0.7:100.

[0037] S2. Place the mixed oxide slurry obtained in step S1 in an oven at 120℃-180℃ and dry for 8h-12h, then pass it through a 60-mesh sieve to obtain mixed oxide powder.

[0038] S3. The mixed oxide powder obtained in step S2 is loaded into a corundum mullite sagger and placed in a box furnace for pre-firing for 3-6 hours at a pre-firing temperature of 1050℃-1200℃.

[0039] S4. Place the pre-calcined powder from step S3 into a ball mill. Add the corresponding zirconium balls and pure water according to the ratio of raw material: zirconium balls: pure water = 1:2.0:1.2. Add a small amount of dispersant and defoamer. Grind in the ball mill at 260 rpm for 10-18 hours. After grinding, discharge and sieve to obtain mixed oxide slurry II. The dispersant and defoamer in this step are ammonium polyacrylate and tributyl phosphate, respectively. The mass ratio of the amount of dispersant and defoamer added to the total amount of raw material is 0.4-0.7:100 and 0-0.4:100, respectively.

[0040] S5. Place the mixed oxide slurry obtained in step S4 in an oven at 120℃-180℃ and dry for 8h-12h, then sieve to obtain mixed oxide powder.

[0041] S6. Add 8wt%-12wt% of PVA adhesive aqueous solution to the sieved mixed oxides, mix thoroughly, and then extrude and crush. Pass the uniformly mixed powder through a 60-mesh sieve and bake in a 90℃ oven for 5 minutes to obtain a granulated mixture;

[0042] S7. Press the granulated powder into a green body; press the granulated powder into a cylindrical green body with a diameter of D16.4*H8.0 under a pressure of 15T; sinter the pressed small cylinder at a temperature of 1420℃ for 6 hours to obtain the product.

[0043] The performance test results of the tunable temperature drift dielectric microwave dielectric ceramic material prepared using the method of this embodiment are shown in Table 1.

[0044] Examples 6-9

[0045] The method for preparing the adjustable temperature-drift dielectric microwave ceramic material in this embodiment uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 is stoichiometrically prepared, where x = a2 (0.64 ≤ a2 ≤ 0.70), y = b, and b is selected as b1, b2, b3, b4, b5, with b1, b2, b3, b4, b5 increasing in a regular pattern (0 ≤ b ≤ 0.2). During preparation, calcium carbonate, strontium carbonate, and titanium dioxide are added sequentially to obtain mixture one; then lanthanum trioxide, yttrium trioxide, and aluminum oxide are mixed to obtain mixture two.

[0046] S1. Mixture 1 and Mixture 2 are mixed together according to the metering ratio, a dispersant is added, and the mixture is ball-milled for 15-20 hours. The discharged material is sieved to obtain mixed oxide slurry 1.

[0047] S2. Place the mixed oxide slurry obtained in step S1 in an oven at 120℃-180℃ and dry for 8-12 hours. Then pass it through a 60-mesh sieve to obtain mixed oxide powder.

[0048] S3. The mixed oxide powder obtained in step S2 is loaded into a corundum mullite sagger and placed in a box furnace for pre-firing for 3-6 hours at a pre-firing temperature of 1050℃-1200℃.

[0049] S4. Place the pre-calcined powder from step S3 into a ball mill. Add the corresponding zirconium balls and pure water according to the ratio of raw material: zirconium balls: pure water = 1:2.0:1.2. Add a small amount of dispersant and defoamer. Grind in the ball mill at 260 rpm for 10-18 hours. After grinding, discharge and sieve to obtain mixed oxide slurry II. The dispersant and defoamer in this step are ammonium polyacrylate and tributyl phosphate, respectively. The mass ratio of the amount of dispersant and defoamer added to the total amount of raw material is 0.4-0.7:100 and 0-0.4:100, respectively.

[0050] S5. Place the mixed oxide slurry obtained in step S4 in an oven at 120℃-180℃ and dry for 8h-12h, then sieve to obtain mixed oxide powder.

[0051] S6. Add 8wt%-12wt% of PVA adhesive aqueous solution to the sieved mixed oxides, mix thoroughly, and then extrude and crush. Pass the uniformly mixed powder through a 60-mesh sieve and bake in a 90℃ oven for 5 minutes to obtain a granulated mixture;

[0052] S7. Press the granulated powder into a green body. Press the granulated powder into a cylindrical green body with a diameter of D16.4*H8.0 under a pressure of 15T. Sinter the pressed small cylinder at a set temperature of 1385℃ for 4 hours to obtain the product.

[0053] The performance test results of the tunable temperature drift dielectric microwave dielectric ceramic material prepared using the method of this embodiment are shown in Table 1.

[0054] Examples 10-13

[0055] The method for preparing the adjustable temperature-drift dielectric microwave ceramic material in this embodiment uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in accordance with xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 is stoichiometrically prepared, where x = a2 (0.64 ≤ a2 ≤ 0.70), y = b, and b is selected as b1, b2, b3, b4, b5, with b1, b2, b3, b4, b5 increasing in a regular pattern (0 ≤ b ≤ 0.2). During preparation, calcium carbonate, strontium carbonate, and titanium dioxide are added sequentially to obtain mixture one; then lanthanum trioxide, yttrium trioxide, and aluminum oxide are mixed to obtain mixture two.

[0056] The preparation method is largely the same as that of Examples 6-9, except that the product is obtained by sintering at 1410°C for 6 hours.

[0057] The performance test results of the tunable temperature drift dielectric microwave dielectric ceramic material prepared using the method of this embodiment are shown in Table 1. Comparative Example 1

[0058] The ceramic material preparation method of Comparative Example 1 uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in a 0.6Ca ratio. 0.9 Sr 0.1 The TiO3+0.4LaAlO3 was prepared using the same method as in Example 1, and the performance test results are shown in Table 1. Comparative Example 2

[0059] The ceramic material preparation method of Comparative Example 2 uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in a ratio of 0.75Ca. 0.9Sr 0.1 TiO3+0.25La 0.9 Y 0.1 The AlO3 was prepared using the same method as in Example 1, and the performance test results are shown in Table 1. Comparative Example 3

[0060] The preparation method of the ceramic material in Comparative Example 2 uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in a ratio of 0.8Ca... 0.9 Sr 0.1 TiO3+0.2La 0.9 Y 0.1 The AlO3 was prepared using the same method as in Example 1, and the performance test results are shown in Table 1. Comparative Example 4

[0061] The preparation method of the ceramic material in Comparative Example 3 uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in a ratio of 0.85Ca. 0.9 Sr 0.1 TiO3+0.15La 0.9 Y 0.1 The AlO3 was prepared using the same method as in Example 1, and the performance test results are shown in Table 1. Comparative Example 5

[0062] The ceramic material preparation method of Comparative Example 4 uses calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials in a ratio of 0.6Ca... 0.9 Sr 0.1 The TiO3+0.4YAlO3 metering ratio and its preparation method are largely the same as those in Examples 6-9, except that the product is obtained by sintering at 1400℃ for 10 hours.

[0063] The performance test results are shown in Table 1.

[0064]

[0065] The experimental results show that the resonant frequency temperature coefficient of the tunable temperature-drift dielectric microwave dielectric ceramic material of this invention can be adjusted by gradient variation. YAlO3, with its negative temperature coefficient and low dielectric constant, can effectively compensate for the positive temperature coefficient and adjust the dielectric constant of most materials by changing the substitution amount of Y and Ca. 0.9 Sr 0.1By adjusting the proportion of TiO3, a dielectric microwave dielectric ceramic material with a lower sintering temperature, a suitable dielectric constant, a lower dielectric loss, and a near-zero resonant frequency temperature coefficient can be obtained. Furthermore, while maintaining a relatively stable Qf value, the resonant frequency temperature coefficient and dielectric constant of this dielectric microwave dielectric ceramic material can be adjusted by gradient changes, which can better meet the different performance requirements of various microwave RF devices for materials.

[0066] Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the present invention, which should be defined by the claims.

Claims

1. A temperature-drift dielectric microwave dielectric ceramic material, characterized in that, Its raw material chemical composition is based on xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y The AlO3 is stoichiometrically prepared, with x = 0.6-0.7 and y = 0.05-0.2; and sintered at a temperature of 1385℃-1420℃. The microwave dielectric ceramic has a dielectric constant Er = 37-46, a quality factor Qf = 19500-26000GHz, and a resonant frequency temperature coefficient τf = -24ppm / ℃ to +7ppm / ℃.

2. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to claim 1, characterized in that, Using calcium carbonate, strontium carbonate, titanium dioxide, lanthanum trioxide, yttrium trioxide, and alumina as raw materials, according to xCa 0.9 Sr 0.1 TiO3+(1-x)La (1-y) Y y AlO3 was measured and mixed in the following order: calcium carbonate, strontium carbonate, and titanium dioxide were added sequentially to obtain mixture one; then lanthanum trioxide, yttrium trioxide, and aluminum oxide were mixed to obtain mixture two.

3. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to claim 2, characterized in that, Includes the following steps: S1. Mixture 1 and Mixture 2 are mixed together according to the metering ratio, a dispersant is added, and the mixture is ball-milled for 10-18 hours. The discharged material is sieved to obtain Mixed Oxide Slurry 1. S2. Place the mixed oxide slurry obtained in step S1 in an oven at 120℃-180℃ and dry for 8h-12h, then pass it through a sieve to obtain mixed oxide powder. S3. The mixed oxide powder obtained in step S2 is loaded into a corundum mullite sagger and placed in a box furnace for pre-firing for 3-6 hours at a pre-firing temperature of 1050-1200℃. S4. Place the pre-calcined powder from step S3 into a ball mill. Add the corresponding zirconium balls and pure water according to the ratio of raw material: zirconium balls: pure water = 1:2.0-3.0:1.0-2.

0. Add a small amount of dispersant and defoamer. Grind in the ball mill for 10-18 hours. Then, discharge and sieve to obtain mixed oxide slurry II. S5. Place the mixed oxide slurry obtained in step S4 in an oven at 120℃-180℃ and dry for 8h-12h, then sieve to obtain mixed oxide powder. S6. Add 8wt%-12wt% of PVA adhesive aqueous solution to the sieved mixed oxides, mix thoroughly, and then extrude, crush, and sieve to obtain a granulated mixture; S7. Press the granulated powder into a green body; sinter it at a set temperature of 1385℃-1420℃ for 4h-8h to obtain the product.

4. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to claim 3, characterized in that, The raw materials of Mixture 1 are added in the following ratio: Mixture 1: Grinding media 1: Water = 1:1.5-3.0:1.0-1.5, and ball milling is performed for the first time; the raw materials of Mixture 2 are added in the following ratio: Mixture 2: Grinding media 2: Water = 1:1.0-3.0:1.0-1.5, and ball milling is performed for the second time.

5. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to claim 3, characterized in that, The dispersant in step S1 is ammonium polyacrylate, and the mass ratio of the amount of dispersant added to the total amount of raw materials is 0.4-0.7:

100.

6. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to any one of claims 3-5, characterized in that, The rotation speeds for the first ball milling, the second ball milling, and the grinding were all between 200 rpm and 300 rpm. The total ball milling time was 10 h to 20 h, and the grinding time was 10 h to 18 h.

7. The method for preparing the adjustable temperature-drift dielectric microwave dielectric ceramic material according to claim 6, characterized in that, The dispersant and defoamer in step S4 are ammonium polyacrylate and tributyl phosphate, respectively, and the mass ratio of the amount of dispersant and defoamer added to the total amount of raw materials is 0.4-0.7:100 and 0-0.4:100, respectively.

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