A kind of microwave dielectric ceramic material and preparation method thereof

Abstract

The invention provides a microwave dielectric ceramic material. The microwave dielectric ceramic material is prepared from a mixture of a composite oxide and sintering aids, wherein the general formula of the composite oxide is xLa2O3-ySrO-zAl2O3-wTiO2; and in the formula (I), x is more than 0 and less than 10, y is more than or equal to 0 and less than 5, z is more than 0 and less than 10, and wis more than or equal to 0 and less than 5. Compared with the prior art, the microwave dielectric ceramic material provided by the invention has the advantages that a crystal structure of the microwave dielectric ceramic material is changed among a KNi2F4 structure, a composite perovskite structure and a simple perovskite structure along with proportional change of x, y, z and w in a main component xLa2O3-ySrO-zAl2O3-wTiO2, so that the microwave dielectric ceramic material has relatively high dielectric constant and extremely low dielectric loss; and as Ti particle content is increased, frequency-temperature coefficient of the microwave dielectric ceramic material is in an increasing trend in a certain range. Experimental results show that the microwave dielectric ceramic material has thedielectric constant of 18.2-50, Q*f value can reach 110000GHz, and the frequency-temperature coefficient is adjustable in a range from -30ppm / K to +35ppm / K.

Description

technical field

[0001] The invention relates to the field of new materials and microwave communication, and more specifically relates to a microwave dielectric ceramic material and a preparation method thereof. Background technique

[0002] As a next-generation mobile communication technology, LTE has become an inevitable path for communication operators to develop future communication networks. However, many challenges such as tight spectrum resources, high energy consumption, and high costs also make operators face more severe cost pressures. In 2015, my country can plan about 1000MHz bandwidth spectrum resources for public mobile communications, but there is still a gap of about 300MHz from the total bandwidth demand of 1360MHz estimated by the Ministry of Industry and Information Technology's Telecommunications Research Institute, and spectrum resources are tight. Therefore, how to improve spectrum utilization becomes a technical problem to be solved urgently by those s...

Examples

preparation example Construction

[0047] The present invention also provides a preparation method of the microwave dielectric ceramic material described in the above technical solution, comprising the following steps:

[0048] a) mixing lanthanum oxide, strontium carbonate, aluminum oxide, titanium dioxide and water, performing fermentation and sand grinding for the first time in sequence to obtain the first raw material mixture;

[0049] b) After the first raw material mixture obtained in step a) is dried for the first time, it is pre-calcined to obtain a pre-fired material;

[0050] c) crushing and sieving the calcined material obtained in step b), mixing it with a sintering aid and water, and performing a second sand mill to obtain a second raw material mixture;

[0051] d) After the second raw material mixture obtained in step c) is dried for the second time, sieving and compression molding are carried out in sequence to obtain a compression molding material;

[0052] e) Sintering the pressed molding mate...

Embodiment 1

[0082] (1) According to xLa in Table 1 2 o 3 -ySrO-zAl 2 o 3 -wTiO 2 The stoichiometric ratio is weighed and mixed with lanthanum oxide, strontium carbonate, aluminum oxide and titanium dioxide to obtain the first mixture; then add water equal to the quality of the first mixture, stir and ferment with a mixer for 24 hours, and then use a sand mill to Sanding for 1h to obtain a particle size range of 0.1μm≤D 0.5 ≤ 0.3 μm of the first raw material mixture.

[0083] (2) After discharging the first raw material mixture obtained in step (1), use a spray drying tower to spray dry at 220°C, then heat up to 1250°C at a heating rate of 3°C / min, and then preheat at 1250°C Burn for 5 hours and cool with the furnace to obtain pre-fired material.

[0084] (3) After pulverizing the calcined material obtained in step (2), pass through an 80-mesh sieve, add the sintering aid of the specific content (relative to the mass of the calcined material) in Table 1, stir it evenly with a mixer, ...

Embodiment 2

[0088] (1) According to xLa in Table 1 2 o 3 -ySrO-zAl 2 o 3 -wTiO 2 The stoichiometric ratio is weighed and mixed with lanthanum oxide, strontium carbonate, aluminum oxide and titanium dioxide to obtain the first mixture; then add water equal to the quality of the first mixture, stir and ferment with a mixer for 24 hours, and then use a sand mill to Sanding for 1h to obtain a particle size range of 0.1μm≤D 0.5 ≤ 0.3 μm of the first raw material mixture.

[0089] (2) After discharging the first raw material mixture obtained in step (1), use a spray drying tower to spray dry at 220° C., then raise the temperature to 1100° C. at a heating rate of 3° C. / min, and then preheat at 1100° C. Burn for 6 hours and cool with the furnace to obtain pre-fired material.

[0090] (3) After the calcined material obtained in step (2) is pulverized, pass through an 80-mesh sieve, add the sintering aid of the specific content (relative to the quality of the calcined material) component in T...

technical field

[0001] The invention relates to the field of new materials and microwave communication, and more specifically relates to a microwave dielectric ceramic material and a preparation method thereof. Background technique

[0002] As a next-generation mobile communication technology, LTE has become an inevitable path for communication operators to develop future communication networks. However, many challenges such as tight spectrum resources, high energy consumption, and high costs also make operators face more severe cost pressures. In 2015, my country can plan about 1000MHz bandwidth spectrum resources for public mobile communications, but there is still a gap of about 300MHz from the total bandwidth demand of 1360MHz estimated by the Ministry of Industry and Information Technology's Telecommunications Research Institute, and spectrum resources are tight. Therefore, how to improve spectrum utilization becomes a technical problem to be solved urgently by those s...

Examples

preparation example Construction

[0047] The present invention also provides a preparation method of the microwave dielectric ceramic material described in the above technical solution, comprising the following steps:

[0048] a) mixing lanthanum oxide, strontium carbonate, aluminum oxide, titanium dioxide and water, performing fermentation and sand grinding for the first time in sequence to obtain the first raw material mixture;

[0049] b) After the first raw material mixture obtained in step a) is dried for the first time, it is pre-calcined to obtain a pre-fired material;

[0050] c) crushing and sieving the calcined material obtained in step b), mixing it with a sintering aid and water, and performing a second sand mill to obtain a second raw material mixture;

[0051] d) After the second raw material mixture obtained in step c) is dried for the second time, sieving and compression molding are carried out in sequence to obtain a compression molding material;

[0052] e) Sintering the pressed molding mate...

Embodiment 1

[0082] (1) According to xLa in Table 1 2 o 3 -ySrO-zAl 2 o 3 -wTiO 2 The stoichiometric ratio is weighed and mixed with lanthanum oxide, strontium carbonate, aluminum oxide and titanium dioxide to obtain the first mixture; then add water equal to the quality of the first mixture, stir and ferment with a mixer for 24 hours, and then use a sand mill to Sanding for 1h to obtain a particle size range of 0.1μm≤D 0.5 ≤ 0.3 μm of the first raw material mixture.

[0083] (2) After discharging the first raw material mixture obtained in step (1), use a spray drying tower to spray dry at 220°C, then heat up to 1250°C at a heating rate of 3°C / min, and then preheat at 1250°C Burn for 5 hours and cool with the furnace to obtain pre-fired material.

[0084] (3) After pulverizing the calcined material obtained in step (2), pass through an 80-mesh sieve, add the sintering aid of the specific content (relative to the mass of the calcined material) in Table 1, stir it evenly with a mixer, ...

Embodiment 2

[0088] (1) According to xLa in Table 1 2 o 3 -ySrO-zAl 2 o 3 -wTiO 2 The stoichiometric ratio is weighed and mixed with lanthanum oxide, strontium carbonate, aluminum oxide and titanium dioxide to obtain the first mixture; then add water equal to the quality of the first mixture, stir and ferment with a mixer for 24 hours, and then use a sand mill to Sanding for 1h to obtain a particle size range of 0.1μm≤D 0.5 ≤ 0.3 μm of the first raw material mixture.

[0089] (2) After discharging the first raw material mixture obtained in step (1), use a spray drying tower to spray dry at 220° C., then raise the temperature to 1100° C. at a heating rate of 3° C. / min, and then preheat at 1100° C. Burn for 6 hours and cool with the furnace to obtain pre-fired material.

[0090] (3) After the calcined material obtained in step (2) is pulverized, pass through an 80-mesh sieve, add the sintering aid of the specific content (relative to the quality of the calcined material) component in T...

Images