CN110845226A - Microwave dielectric ceramic material SrGa2O4And method for preparing the same - Google Patents

Abstract

The invention belongs to the technical field of ceramic materials, and in particular relates to a microwave dielectric ceramic material SrGa ₂ O ₄ with low dielectric constant and high quality factor and a preparation method thereof. The main raw materials are SrCO ₃ and Ga ₂ O ₃ high-purity powder. The method mainly includes: batching, primary ball milling, pre-sintering, secondary ball milling, granulation and tableting, and sintering. The low dielectric constant microwave dielectric ceramic material SrGa ₂ O ₄ with excellent microwave dielectric properties can be obtained by adjusting the preparation process and sintering temperature, which has great application value in the field of future millimeter wave band wireless communication technology.

Description

A kind of microwave dielectric ceramic material SrGa2O4 and preparation method thereof

technical field

The invention belongs to the technical field of ceramic materials, in particular to a microwave dielectric ceramic material SrGa ₂ O ₄ with low dielectric constant and high quality factor and a preparation method thereof.

Background technique

With the gradual development of wireless communication technologies such as mobile phone communication, WIFI, satellite and radar communication, etc. towards the sub-millimeter wave-millimeter wave band, microwave ceramic materials as key components such as filters, resonators, and oscillators in wireless communication systems have become a Key materials for the development of millimeter-wave communications. Different from 2G/3G/4G communication working in the frequency band below 6GHz, in the future submillimeter wave (24GHz-30GHz) and millimeter wave band (60GHz-78GHz) communication, in order to ensure extremely fast signal propagation speed, the signal delay time is required to be less than 1 millisecond. Therefore, microwave dielectric ceramics are required to have the lowest possible dielectric constant ( _εr <10) in millimeter-wave communication components to improve the signal response of microwave devices and reduce the delay of microwave signal transmission; at the same time, microwave ceramics need to have high Qf value (Qf>20000GHz) to enhance the frequency selection characteristics of the device and reduce the energy transfer loss. In recent years, with the advancement of 5G communication research and industrial layout, the demand for high-end components in (sub)millimeter wave communication circuits has increased dramatically. In order to promote the development of information technology, the development of low dielectric constant microwave dielectric ceramics with high signal transmission, fast response speed, strong temperature stability, high signal transmission quality, low transmission loss and good frequency selectivity has become a research topic in the field of communication in various countries. important topic.

Therefore, there is an urgent need in the art to develop a new microwave dielectric ceramic material to enrich the material requirements of passive devices in the (sub) millimeter waveband.

SUMMARY OF THE INVENTION

Aiming at the needs of the existing information communication technology field developing towards submillimeter wave-millimeter wave high-frequency communication, the present invention provides a microwave dielectric ceramic material SrGa ₂ O ₄ with low dielectric constant and high quality factor and a preparation method thereof.

In order to achieve the above-mentioned purpose of the invention, the present invention adopts the following technical solutions:

A preparation method of microwave dielectric ceramic material SrGa ₂ O ₄ , comprising the following steps:

(1) batching: the raw materials SrCO ₃ and Ga ₂ O ₃ are proportioned according to the stoichiometric ratio of SrGa ₂ O ₄ 1:1;

(2) mixing: the material, ball milling beads and dehydrated alcohol obtained by batching are placed in a ball mill according to the mass ratio of 1:4:2.5 to carry out wet ball milling, and the ball milling time is 6h to obtain mud-like raw materials;

(3) drying: the slurry-like raw material of step (2) is placed in an oven and dried to constant weight to obtain a dry mixture;

(4) Pre-sintering: the mixture in step (3) is sieved and dispersed, and then placed in a high-temperature furnace for pre-sintering for 3 hours, and the pre-sintering temperature is 1000-1100° C. to obtain SrGa ₂ O ₄ powder;

(5) Ball milling: adding the SrGa ₂ O ₄ powder of step (4) to absolute ethanol, and placing it in a ball mill to grind for 6 hours to form SrGa ₂ O ₄ slurry;

(6) drying: the SrGa ₂ O ₄ slurry of step (5) is placed in an oven and dried to constant weight to obtain SrGa ₂ O ₄ compound powder;

(7) Granulation: pass the SrGa ₂ O ₄ compound powder of step (6) through a 100-mesh standard sieve, take the sieve material and add it to the polyvinyl alcohol solution, after mixing evenly, pass the powder particles through a 60-mesh standard sieve, take out the sieve The material is pressed into a cylindrical green body;

(8) Debinding: place the green cylindrical body in a high-temperature furnace to heat up to 650°C at a rate of 5°C/min, and keep the temperature for 2h;

(9) Sintering: sintering the green cylindrical body after the debinding treatment to obtain the microwave dielectric ceramic material SrGa ₂ O ₄ .

As a preferred solution, the sintering process includes: raising the temperature to 1200-1300°C for 3 hours at a rate of 5°C/min, then cooling to 1100°C at a rate of 1°C/min, and finally cooling down naturally.

As a preferred solution, the addition amount of the polyvinyl alcohol solution is 4-6 wt % of the mass of the SrGa ₂ O ₄ compound powder.

As a preferred solution, before batching, the raw materials are respectively put into a ball mill for continuous ball milling for more than 6 hours; wherein, the mass ratio of raw materials, zirconia ball milling medium, and anhydrous ethanol is 1:4:2.5.

As a preferred version, the step (9) also includes the following steps after:

(10) Post-processing: grinding and polishing the sintered microwave dielectric ceramic material SrGa ₂ O ₄ .

As a preferred solution, the purity of the SrCO ₃ is 99.99%, and the purity of the Ga ₂ O ₃ is 99.99%.

As a preferred solution, the ball mill is a planetary ball mill, and the rotational speed is 180 r/min.

As a preferred solution, the calcination temperature in the step (4) is 1100°C.

As a preferred solution, the cylindrical green body has a diameter of 12 mm and a height of 5 mm.

The invention also provides the microwave dielectric ceramic material SrGa ₂ O ₄ prepared by the preparation method according to any one of the above schemes, the dielectric constant _εr is in the range of 8.97-9.22, the quality factor Qf is in the range of 26136-66000GHz, and the resonant frequency temperature coefficient is in the range of 8.97-9.22. The range of τ _f is -79.7～-85.6ppm/°C.

Compared with the prior art, the present invention has the following beneficial effects:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ of the present invention is a standard solid-state reaction method, the preparation method is simple, and the production cost is low.

By designing the sintering temperature of the ceramic, the microwave dielectric ceramic material SrGa ₂ O ₄ with low dielectric constant (8.97～9.22) and high quality factor (26136～66000GHz) can be stably obtained, and the range of its resonant frequency temperature coefficient τ _f is - 79.7～-85.6ppm/℃.

Description of drawings

Fig. 1 is the XRD pattern of the microwave dielectric ceramic material SrGa ₂ O ₄ prepared in Example 1 of the present invention;

Fig. 2 is a graph showing the variation of dielectric constant with sintering temperature of the microwave dielectric ceramic material SrGa ₂ O ₄ prepared in Examples 1-5 of the present invention;

FIG. 3 is a graph showing the variation of quality factor with sintering temperature of the microwave dielectric ceramic material SrGa ₂ O ₄ prepared in Examples 1-5 of the present invention;

4 is a graph showing the variation of the temperature coefficient of resonance frequency with the sintering temperature of the microwave dielectric ceramic material SrGa ₂ O ₄ prepared in Examples 1 to 5 of the present invention.

Detailed ways

The technical solutions of the present invention will be further described and illustrated below through specific embodiments.

Example 1:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ in this embodiment includes the following steps:

(1) Ingredients: SrCO ₃ (purity 99.99%) and Ga ₂ O ₃ (purity 99.99%) were proportioned according to the stoichiometric 1:1 of SrGa ₂ O ₄ ; specifically, 10.1492g SrCO ₃ and 12.8812g Ga were weighed in turn. ₂ O ₃ raw material.

(2) Mixing: Pour the above mixture into a ball mill, add ball milling medium and dehydrated ethanol in a mass ratio of 1:4:2.5, place it in a planetary ball mill, and mill it at a rotational speed of 180 r/min for 6 hours to obtain slurry;

(3) drying: pour out the ball-milled slurry, put it in an oven and dry to constant weight at 70°C to obtain a dry mixture;

(4) Pre-sintering: grind the dry mixture obtained in the previous step in a mortar and then pass through a 100-mesh standard sieve. After dispersing the mixture, put it into a high-temperature furnace for pre-sintering for 3 hours. The pre-sintering temperature is 1100°C, and the heating rate is 5 ℃/min, make the mixture preliminarily react to synthesize SrGa ₂ O ₄ compound;

(5) Ball milling: adding 50 g of dehydrated alcohol to the preliminarily synthesized SrGa ₂ O ₄ compound and placing it in a ball mill to grind for 6 hours at a rotational speed of 180 r/min to form a SrGa ₂ O ₄ compound with a refined particle size;

(6) drying: take out the SrGa ₂ O ₄ compound slurry, and place it in an oven to dry to constant weight at 70° C. to obtain a preliminary synthesized SrGa ₂ O ₄ compound;

(7) Granulation: pass the constant weight SrGa ₂ O ₄ compound obtained in the previous step through a 60-mesh standard sieve to disperse the particles uniformly, and then add a polyvinyl alcohol solution (PVA) as a viscous solution according to the 6wt% mass percentage of the SrGa ₂ O ₄ compound. Mixture, after mixing evenly, the powder is placed in a mold and pressed into a cylindrical green body with a diameter of 12mm and a thickness of about 5mm under a pressure of 200Mpa;

(8) Debinding: place the pressed cylinder in a high temperature furnace and heat it up to 650°C at a rate of 5°C/min, and keep it for 2 hours to remove PVA in the cylinder;

(9) Sintering: Sintering: after debinding, the temperature was raised to 1200°C for 3 hours at a rate of 5°C/min, then cooled to 1100°C at a rate of 1°C/min, and finally set to natural cooling;

(10) Post-processing: grinding and polishing the sintered SrGa ₂ O ₄ ceramic to obtain a finished ceramic product with a smooth surface.

As shown in FIG. 1 , the XRD pattern of the microwave dielectric ceramic material SrGa ₂ O ₄ of the present embodiment indicates that the microwave dielectric ceramic material is SrGa ₂ O ₄ . The XRD patterns of the following examples are the same as those in this example.

Example 2:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ in this embodiment includes the following steps:

(1) Ingredients: SrCO ₃ (purity 99.99%) and Ga ₂ O ₃ (purity 99.99%) were proportioned according to the stoichiometric 1:1 of SrGa ₂ O ₄ ; specifically, 10.1492g SrCO ₃ and 12.8812g Ga were weighed in turn. ₂ O ₃ raw material.

(2) Mixing: Pour the above mixture into a ball mill, add ball milling medium and dehydrated ethanol in a mass ratio of 1:4:2.5, place it in a planetary ball mill, and mill it at a rotational speed of 180 r/min for 6 hours to obtain slurry;

(3) drying: pour out the ball-milled slurry, put it in an oven and dry to constant weight at 70°C to obtain a dry mixture;

(4) Pre-sintering: grind the dry mixture obtained in the previous step in a mortar and then pass through a 100-mesh standard sieve. After dispersing the mixture, put it into a high-temperature furnace for pre-sintering for 3 hours. The pre-sintering temperature is 1100°C, and the heating rate is 5 ℃/min, make the mixture preliminarily react to synthesize SrGa ₂ O ₄ compound;

(5) Ball milling: adding 50 g of dehydrated alcohol to the preliminarily synthesized SrGa ₂ O ₄ compound and placing it in a ball mill to grind for 6 hours at a rotational speed of 180 r/min to form a SrGa ₂ O ₄ compound with a refined particle size;

(6) drying: take out the SrGa ₂ O ₄ compound slurry, and place it in an oven to dry to constant weight at 70° C. to obtain a preliminary synthesized SrGa ₂ O ₄ compound;

(7) Granulation: pass the constant weight SrGa ₂ O ₄ compound obtained in the previous step through a 60-mesh standard sieve to disperse the particles uniformly, and add a polyvinyl alcohol solution (PVA) as a binding agent according to the 6wt% mass percentage of the SrGa ₂ O ₄ compound. After mixing uniformly, the powder is placed in a mold and pressed into a cylindrical green body with a diameter of 12mm and a thickness of about 5mm under a pressure of 200Mpa;

(8) Debinding: place the pressed cylinder in a high temperature furnace and heat it up to 650°C at a rate of 5°C/min, and keep it for 2 hours to remove PVA in the cylinder;

(9) Sintering: Sintering: after debinding, the temperature is raised to 1225°C for 3 hours at a rate of 5°C/min, then cooled to 1100°C at a rate of 1°C/min, and finally set to natural cooling;

(10) Post-processing: grinding and polishing the sintered SrGa ₂ O ₄ ceramic to obtain a finished ceramic product with a smooth surface.

Example 3:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ in this embodiment includes the following steps:

(1) Ingredients: SrCO ₃ (purity 99.99%) and Ga ₂ O ₃ (purity 99.99%) were proportioned according to the stoichiometric 1:1 of SrGa ₂ O ₄ ; specifically, 10.1492g SrCO ₃ and 12.8812g Ga were weighed in turn. ₂ O ₃ raw material.

(2) Mixing: Pour the above mixture into a ball mill, add ball milling medium and dehydrated ethanol in a mass ratio of 1:4:2.5, place it in a planetary ball mill, and mill it at a rotational speed of 180 r/min for 6 hours to obtain slurry;

(3) drying: pour out the ball-milled slurry, put it in an oven and dry to constant weight at 70°C to obtain a dry mixture;

(4) Pre-sintering: grind the dry mixture obtained in the previous step in a mortar and then pass through a 100-mesh standard sieve. After dispersing the mixture, put it into a high-temperature furnace for pre-sintering for 3 hours. The pre-sintering temperature is 1100°C, and the heating rate is 5 ℃/min, make the mixture preliminarily react to synthesize SrGa ₂ O ₄ compound;

(5) Ball milling: adding 50 g of dehydrated alcohol to the preliminarily synthesized SrGa ₂ O ₄ compound and placing it in a ball mill to grind for 6 hours at a rotational speed of 180 r/min to form a SrGa ₂ O ₄ compound with a refined particle size;

(6) drying: take out the SrGa ₂ O ₄ compound slurry, and place it in an oven to dry to constant weight at 70° C. to obtain a preliminary synthesized SrGa ₂ O ₄ compound;

(7) Granulation: pass the constant weight SrGa ₂ O ₄ compound obtained in the previous step through a 60-mesh standard sieve to disperse the particles uniformly, and add a polyvinyl alcohol solution (PVA) as a binding agent according to the 6wt% mass percentage of the SrGa ₂ O ₄ compound. After mixing uniformly, the powder is placed in a mold and pressed into a cylindrical green body with a diameter of 12mm and a thickness of about 5mm under a pressure of 200Mpa;

(8) Debinding: place the pressed cylinder in a high temperature furnace and heat it up to 650°C at a rate of 5°C/min, and keep it for 2 hours to remove PVA in the cylinder;

(9) Sintering: Sintering: after debinding, the temperature was raised to 1250°C for 3 hours at a rate of 5°C/min, then cooled to 1100°C at a rate of 1°C/min, and finally set to natural cooling;

(10) Post-processing: grinding and polishing the sintered SrGa ₂ O ₄ ceramic to obtain a finished ceramic product with a smooth surface.

Example 4:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ in this embodiment includes the following steps:

(1) Ingredients: SrCO ₃ (purity 99.99%) and Ga ₂ O ₃ (purity 99.99%) were proportioned according to the stoichiometric 1:1 of SrGa ₂ O ₄ ; specifically, 10.1492g SrCO ₃ and 12.8812g Ga were weighed in turn. ₂ O ₃ raw material.

(2) Mixing: Pour the above mixture into a ball mill, add ball milling medium and dehydrated ethanol in a mass ratio of 1:4:2.5, place it in a planetary ball mill, and mill it at a rotational speed of 180 r/min for 6 hours to obtain slurry;

(3) drying: pour out the ball-milled slurry, put it in an oven and dry to constant weight at 70°C to obtain a dry mixture;

(4) Pre-sintering: grind the dry mixture obtained in the previous step in a mortar and then pass through a 100-mesh standard sieve. After dispersing the mixture, put it into a high-temperature furnace for pre-sintering for 3 hours. The pre-sintering temperature is 1100°C, and the heating rate is 5 ℃/min, make the mixture preliminarily react to synthesize SrGa ₂ O ₄ compound;

(5) Ball milling: adding 50 g of dehydrated alcohol to the preliminarily synthesized SrGa ₂ O ₄ compound and placing it in a ball mill to grind for 6 hours at a rotational speed of 180 r/min to form a SrGa ₂ O ₄ compound with a refined particle size;

(6) drying: take out the SrGa ₂ O ₄ compound slurry, and place it in an oven to dry to constant weight at 70° C. to obtain a preliminary synthesized SrGa ₂ O ₄ compound;

(7) Granulation: pass the constant weight SrGa ₂ O ₄ compound obtained in the previous step through a 60-mesh standard sieve to disperse the particles uniformly, and add a polyvinyl alcohol solution (PVA) as a binding agent according to the 6wt% mass percentage of the SrGa ₂ O ₄ compound. After mixing uniformly, the powder is placed in a mold and pressed into a cylindrical green body with a diameter of 12mm and a thickness of about 5mm under a pressure of 200Mpa;

(8) Debinding: place the pressed cylinder in a high temperature furnace and heat it up to 650°C at a rate of 5°C/min, and keep it for 2 hours to remove PVA in the cylinder;

(9) Sintering: Sintering: after debinding, the temperature was raised to 1275°C for 3 hours at a rate of 5°C/min, then cooled to 1100°C at a rate of 1°C/min, and finally set to natural cooling;

(10) Post-processing machining: grinding and polishing the sintered SrGa ₂ O ₄ ceramic to obtain a finished ceramic product with a smooth surface.

Example 5:

The preparation method of the microwave dielectric ceramic material SrGa ₂ O ₄ in this embodiment includes the following steps:

(1) Ingredients: SrCO ₃ (purity 99.99%) and Ga ₂ O ₃ (purity 99.99%) were proportioned according to the stoichiometric 1:1 of SrGa ₂ O ₄ ; specifically, 10.1492g SrCO ₃ and 12.8812g Ga were weighed in turn. ₂ O ₃ raw material.

(2) Mixing: Pour the above mixture into a ball mill, add ball milling medium and dehydrated ethanol in a mass ratio of 1:4:2.5, place it in a planetary ball mill, and mill it at a rotational speed of 180 r/min for 6 hours to obtain slurry;

(3) drying: pour out the ball-milled slurry, put it in an oven and dry to constant weight at 70°C to obtain a dry mixture;

(4) Pre-sintering: grind the dry mixture obtained in the previous step in a mortar and then pass through a 100-mesh standard sieve. After dispersing the mixture, put it into a high-temperature furnace for pre-sintering for 3 hours. The pre-sintering temperature is 1100°C, and the heating rate is 5 ℃/min, make the mixture preliminarily react to synthesize SrGa ₂ O ₄ compound;

(5) Ball milling: adding 50 g of dehydrated alcohol to the preliminarily synthesized SrGa ₂ O ₄ compound and placing it in a ball mill to grind for 6 hours at a rotational speed of 180 r/min to form a SrGa ₂ O ₄ compound with a refined particle size;

(6) drying: take out the SrGa ₂ O ₄ compound slurry, and place it in an oven to dry to constant weight at 70° C. to obtain a preliminary synthesized SrGa ₂ O ₄ compound;

(7) Granulation: pass the constant weight SrGa ₂ O ₄ compound obtained in the previous step through a 60-mesh standard sieve to disperse the particles uniformly, and add a polyvinyl alcohol solution (PVA) as a binding agent according to the 6wt% mass percentage of the SrGa ₂ O ₄ compound. After mixing uniformly, the powder is placed in a mold and pressed into a cylindrical green body with a diameter of 12mm and a thickness of about 5mm under a pressure of 200Mpa;

(8) Debinding: place the pressed cylinder in a high temperature furnace and heat it up to 650°C at a rate of 5°C/min, and keep it for 2 hours to remove PVA in the cylinder;

(9) Sintering: Sintering: after debinding, the temperature was raised to 1300°C for 3 hours at a rate of 5°C/min, then cooled to 1100°C at a rate of 1°C/min, and finally set to natural cooling;

(10) Post-processing: grinding and polishing the sintered SrGa ₂ O ₄ ceramic to obtain a finished ceramic product with a smooth surface.

The dielectric resonant cavity method proposed by Hakki-Coleman is used to test the microwave dielectric properties of the cylindrical ceramic at the resonant frequency. The specific performance parameters are shown in Figure 2-4. Among the above five embodiments, the dielectric constant of the microwave dielectric ceramic material SrGa ₂ O ₄ in Example 1 is the lowest, and the dielectric constant value is 8.97; the quality factor of the microwave dielectric ceramic material SrGa ₂ O ₄ in Example 4 is the highest, which is 66000GHz; the temperature coefficient of resonance frequency of the microwave dielectric ceramic material SrGa ₂ O ₄ in Example 1 is -79.7ppm/°C, and the stability is the best.

In the above embodiment and its alternatives, the pre-burning temperature can also be 1000°C, 1020°C, 1050°C, 1080°C, and the like.

In the above embodiment and its alternatives, the drying temperature in step (3) can also be 60°C, 65°C, 75°C, 80°C, and the like.

In the above embodiment and its alternatives, the drying temperature in step (6) can also be 60°C, 65°C, 75°C, 80°C, and the like.

In the above embodiment and its alternatives, the addition amount of the polyvinyl alcohol solution (PVA) in step (7 ₎ can also be 4wt%, 4.5wt%, 5wt%, 5.5wt% in the mass percentage of the _SrGa2O4 compound %Wait.

In the above embodiment and its alternatives, the pressing pressure in step (7) can also be 100Mpa, 120Mpa, 150Mpa, 160Mpa, 180Mpa and the like.

In the above embodiment and its alternatives, before batching, the raw materials are put into a ball mill for continuous ball milling for more than 6 hours; wherein, the mass ratio of raw materials, zirconia ball milling media, and absolute ethanol is 1:4:2.5, which ensures that the raw material particles are uniformity.

The descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims (10)

1. Microwave dielectric ceramic material SrGa₂O₄The preparation method is characterized by comprising the following steps:

(1) preparing materials: raw material SrCO₃、Ga₂O₃According to SrGa₂O₄1: 1, proportioning;

(2) mixing materials: mixing the materials obtained by the ingredients, ball milling beads and absolute ethyl alcohol according to the proportion of 1: 4: 2.5, putting the mixture into a ball mill for wet ball milling for 6 hours to obtain slurry raw materials;

(3) drying: putting the slurry raw material in the step (2) into an oven to be dried to constant weight to obtain a dry mixture;

(4) pre-burning: sieving and dispersing the mixture obtained in the step (3), and then placing the mixture into a high-temperature furnace for presintering for 3 hours, wherein the presintering temperature is 1000-1100 ℃, so as to prepare SrGa₂O₄Powder;

(5) ball milling: SrGa obtained in the step (4)₂O₄Adding absolute ethyl alcohol into the powder, and placing the powder in a ball mill for grinding for 6 hours to form SrGa₂O₄Sizing agent;

(6) drying: SrGa obtained in the step (5)₂O₄The slurry is placed in an oven to be dried to constant weight to obtain SrGa₂O₄A compound powder;

(7) and (3) granulation: SrGa obtained in the step (6)₂O₄Sieving compound powder with a 100-mesh standard sieve, adding the sieved powder into a polyvinyl alcohol solution, uniformly mixing, sieving powder particles with a 60-mesh standard sieve, and pressing the sieved powder into a cylindrical green body;

(8) rubber discharging: placing the cylindrical green body in a high-temperature furnace, heating to 650 ℃ at the speed of 5 ℃/min, and preserving heat for 2 h;

(9) and (3) sintering: sintering the cylindrical green body subjected to the binder removal treatment to obtain the microwave dielectric ceramic material SrGa₂O₄。

2. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The preparation method is characterized in that the sintering treatment process comprises the following steps: and (3) increasing the temperature to 1200-1300 ℃ at the speed of 5 ℃/min, sintering for 3h, then reducing the temperature to 1100 ℃ at the speed of 1 ℃/min, and finally naturally reducing the temperature.

3. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The method for producing (1) is characterized in that the polyvinyl alcohol solution is added in an amount of SrGa₂O₄4-6 wt% of the compound powder.

4. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The preparation method is characterized in that before the burdening, the raw materials are respectively put into a ball mill to be continuously ball-milled for more than 6 hours; wherein the mass ratio of the raw materials, the zirconia ball-milling medium and the absolute ethyl alcohol is 1: 4: 2.5.

5. a microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The method for preparing (5) is characterized by further comprising the following steps after the step (9):

(10) and (3) later-stage mechanical processing: sintering the microwave dielectric ceramic material SrGa₂O₄And grinding and polishing.

6. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄Characterized in that the SrCO is₃Has a purity of 99.99%, the Ga being₂O₃The purity of (2) was 99.99%.

7. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The preparation method is characterized in that the ball mill is a planetary ball mill, and the rotating speed is 180 r/min.

8. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The production method of (4), wherein the pre-firing temperature in the step (4) is 1100 ℃.

9. A microwave dielectric ceramic material SrGa as claimed in claim 1₂O₄The method for preparing (1), wherein the diameter of the cylindrical green compact is 12mm, and the height is 5 mm.

10. SrGa microwave dielectric ceramic material prepared by the preparation method of any one of claims 1 to 9₂O₄Characterized by a dielectric constant ε_rThe range is 8.97-9.22, the quality factor Qf is 26136-66000 GHz, and the temperature coefficient of resonance frequency tau_fThe range is-79.7 to-85.6 ppm/DEG C.

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