CN100370560C - Dielectric Nonlinear Capacitor Ceramic Material and Its Fabrication Process - Google Patents

Abstract

The invention discloses an antiferroelectric ceramic capacitor material and a preparation process thereof. Partially replace the tetravalent zirconium element in the lead zirconate titanate compound Pb(Zr, Ti) _O3 with positive tetravalent tin element, and partially replace the divalent element in Pb(Zr, Ti) _O3 with positive trivalent lanthanum element lead element, forming a multi-component solid solution with lead vacancies. The chemical composition formula of charge and valence balance is (Pb _1-3z/2 La _z )[(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where the variation of x is between 0.06-0.20, and y The change of z is between 0.20-0.40, and the change of z is between 0.02-0.08; or adding positive divalent strontium or barium elements to partially replace the divalent lead elements in Pb(Zr, Ti)O ₃ , the chemical composition formula It is [(Pb _1-w B _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where B represents positive divalent strontium or barium element, the change of w The amount is between 0.02-0.12. The preparation method adopts the conventional electronic ceramic preparation technology. The antiferroelectric ceramic capacitor prepared by the material of the invention is a nonlinear capacitor, has the characteristics of high energy storage density and high output power, and can be used for miniaturization of capacitors and high-power electric pulse discharge capacitors.

Description

Dielectric Nonlinear Capacitor Ceramic Material and Its Fabrication Process

technical field

The invention belongs to the technical field of materials and components for electric energy storage and release. In particular, it relates to the ceramic material and its manufacturing process for making dielectric nonlinear capacitors.

Background technique

A capacitor is a component used to store and release electrical energy and is widely used in electronics and power instruments. Energy storage density (electrical energy stored per unit volume) is an important performance indicator of a capacitor. The higher the energy storage density of a capacitor, the greater its ability to store and release electrical energy. With the development of high efficiency and miniaturization of electronic and electric equipment, the industry has an urgent need for capacitors with high energy storage density and high output electric power. At present, the materials used to make capacitors are mainly organic and inorganic dielectric materials, and the electric polarization characteristics of the dielectric materials are used to store and release electric energy. For dielectric capacitors, the higher the dielectric coefficient of the dielectric material, the higher the energy storage density of the capacitor. The problems of traditional dielectric materials used to make capacitors are as follows: (1) For linear dielectric materials, their dielectric coefficients are usually relatively small, and it is necessary to increase their energy storage density by applying a high electric field strength, which affects the durability of the material. (2) For ferroelectric materials with high dielectric coefficient, although its dielectric coefficient is relatively high under low field strength conditions, its dielectric coefficient is high under high field strength conditions. The electrical coefficient will be greatly reduced, and ferroelectric ceramics with high dielectric constant usually have lower electrical breakdown strength. Due to the above problems, the improvement of the energy storage density of the capacitor is limited, and the energy storage density of the usual capacitor is in the range of 0.2-0.4 joules/cubic centimeter. It is of great scientific and technological significance to study new capacitor materials to improve their energy storage density and output power.

Antiferroelectric materials can transform from antiferroelectric phase to ferroelectric phase under the action of sufficiently high electric field strength. During this process, the material absorbs electric energy; when the applied electric field is removed, the metastable ferroelectric phase will spontaneously return to The antiferroelectric phase releases the stored electrical energy in the process. This electric field-induced phase transition property of antiferroelectric materials can be used for the storage and release of electrical energy. There are some reports on the application of antiferroelectric materials in capacitors at home and abroad. In the late 1990s, the Sandia National Laboratory in the United States carried out an evaluation study on antiferroelectric ceramics as an electric detonator initiation capacitor, and the Institute of Materials Research at the University of Pennsylvania in the United States carried out research on the discharge characteristics of antiferroelectric films. These works explore the feasibility of antiferroelectric materials in high energy storage and high power capacitor applications, and put forward some guiding suggestions on the performance of antiferroelectric materials for capacitors. The low-titanium lead zirconate titanate compound Pb(Zr _1-x Ti _x )O ₃ (x<0.05) is a commonly used antiferroelectric ceramic material and has been used in the development of explosive energy conversion power supplies. However, lead zirconate titanate antiferroelectric ceramics have problems such as narrow antiferroelectric-ferroelectric phase transition temperature range, wide electric hysteresis, and large strain, which are difficult to meet the requirements of capacitor materials.

Under the support of the Ministry of Science and Technology's major basic research project 973 in the field of materials "Research on Some Basic Issues of Information Functional Ceramics" and the General Armament Department's Weapons and Equipment Pre-research Fund Project "Microstructure Design of Antiferroelectric Phase Change Ceramics", Xi'an Jiaotong University Electronic Materials The Institute of Devices and Devices systematically studied the field-induced (electric field, temperature and pressure, etc.) induced phase transition of modified lead zirconate titanate antiferroelectric materials and the dielectric nonlinear characteristics and fabrication process under strong electric field conditions, and optimized the Antiferroelectric ceramic materials with wide operating temperature range, small dielectric loss, long service life, and greatly improved dielectric coefficient in the operating voltage range and their manufacturing processes are used to make capacitors with high energy storage density and high output power.

Contents of the invention

The purpose of the present invention is to provide an antiferroelectric ceramic material with high energy storage density and high output power capacitor and its manufacturing process, so that the capacitor can be used in a relatively wide range of voltage and temperature, and has a relatively long cycle times.

The idea of the present invention is to use the electric field-induced antiferroelectric-ferroelectric phase transition characteristics of the antiferroelectric material to transform the initial antiferroelectric phase into a ferroelectric phase with the same polarization orientation through the charging voltage to store the electric polarization energy. During discharge, the metastable ferroelectric phase spontaneously recovers into an antiferroelectric phase without macroscopic polarization strength to release electric polarization energy, so as to achieve the purpose of storing and releasing electric energy. The dielectric nonlinear characteristics of the antiferroelectric material in which the permittivity changes sharply with the electric field intensity near the antiferroelectric-ferroelectric conversion electric field are used to improve the energy storage density and output power.

The antiferroelectric capacitor ceramic material of the present invention is characterized in that: the chemical elements in the lead zirconate titanate compound Pb(Zr, Ti) _O are partially replaced with trace chemical elements, and the field-induced ( Electric field, temperature, pressure) induce phase transition properties and improve the density of ceramics.

1. Partially replace the positive tetravalent zirconium element in the lead zirconate titanate compound Pb(Zr, Ti) _O3 with the positive tetravalent tin element, and partially replace the positive trivalent lanthanum element in the Pb(Zr, Ti) _O3 Positive divalent lead element, forming a multi-component antiferroelectric solid solution with lead vacancies. According to the charge and valence balance requirements, the chemical composition formula of the solid solution is (Pb _1-3z/2 La _z )[(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where the variation of x is between 0.06-0.20 Between, the variation of y is between 0.20-0.40, and the variation of z is between 0.02-0.08;

2. Replace the positive divalent lead element in (Pb _1-3z/2 La _z )[(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ with a positive divalent chemical element such as strontium or barium, which The chemical composition formula of charge and valence balance is [(Pb _1-w B _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ .

(1) When B takes Sr element, the chemical formula is written as [(Pb _1-w Sr _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where x is The variation is between 0.04-0.18, the variation of y is between 0.20-0.40, the variation of z is between 0.02-0.10, and the variation of w is between 0.02-0.06;

(2) When B takes Ba element, the chemical formula is written as [(Pb _1-w Ba _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where x is The variation is between 0.04-0.18, the variation of y is between 0.20-0.40, the variation of z is between 0.02-0.10, and the variation of w is between 0.02-0.12;

3. Trace chemical elements for burning can also be added to the material, and the chemical composition formula of its solid solution is written as (Pb _1-3z/2 La _z )[(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ +C , wherein C represents bismuth, nickel or copper element, and the molar atomic variation of C element is between 1% and 2%.

The process for realizing the preparation of the above three types of antiferroelectric ceramic materials is characterized in that: using conventional electronic ceramic preparation methods, including ball milling, pre-sintering, sintering, making metal electrodes, aging and other process conditions to optimize the process:

1. After drying the oxide raw materials or other compound raw materials containing the above elements, weigh them accurately according to the above material formula;

2. In the ball milling process, the raw materials are mixed evenly and the particle size is about 400 nanometers;

3. In the pre-firing process, the powder is pressed into a block and placed in an alumina crucible, sealed and heated to 750-860°C for 1-2 hours, so that the mechanically mixed raw materials undergo a chemical synthesis reaction to form a perovskite crystal phase;

4. In the sintering process, the green body is placed in an alumina crucible, sealed and heated to 1100-1300°C for 2-3 hours, and the ceramics are sintered in an atmosphere rich in lead and oxygen, and the cooling rate is slow;

5. In the aging process, cut, polish and clean the obtained antiferroelectric ceramics to make metal electrodes with excellent electrical conductivity, and then do aging treatment. The aging treatment method is: in room temperature environment, apply an alternating voltage whose electric field strength is 1.5 times of the forward conversion electric field strength of the antiferroelectric ceramic between the positive and negative electrode surfaces of the ceramic and cycle repeatedly for 5-10 times.

When in use, metal wires are connected to the ceramic upper and lower electrode surfaces, and after packaging, it is made into an antiferroelectric ceramic capacitor. Multi-layer capacitors are made by stacking multiple pieces of ceramics and connecting the electrode surfaces between layers in series or in parallel. The operating voltage and temperature range of the capacitor as well as the dielectric constant are changed by adjusting the chemical composition of the material.

Description of drawings

Fig. 1 is the amount of charge per unit electrode area of the antiferroelectric material of the present invention Schematic diagram of the relationship with the applied electric field intensity E.

Fig. 2 is a schematic diagram of storing and releasing electric energy by the antiferroelectric ceramic material of the present invention.

Fig. 3 is the variation curve of the differential permittivity of the antiferroelectric capacitor ceramic material prepared by the present invention with the electric field intensity.

Fig. 4 is the variation curve of the polarization intensity of the antiferroelectric capacitor ceramic material prepared by the present invention with the electric field intensity.

Fig. 5 is the discharge curve of the antiferroelectric ceramic capacitor produced by the present invention in a series circuit of capacitance, inductance and resistance.

Fig. 6 shows that the antiferroelectric ceramic capacitor prepared by the present invention is used as a voltage stabilizer to eliminate the peak of the front edge of the electric pulse.

in:

。该图说明在足够大的外加电场作用下反铁电相转变成亚稳态的铁电相，电荷量迅速增大；在外加电场撤除时铁电相恢复成反铁电相，电荷量迅速减小到零。这里的E_F是使反铁电相转变成铁电相所需要的电场强度阈值，E_B是阻止铁电相恢复成反铁电相的电场强度阈值。In Figure 1, the abscissa is the applied electric field strength E, and the ordinate is the amount of charge on the ceramic unit electrode area

. The figure shows that under the action of a sufficiently large external electric field, the antiferroelectric phase transforms into a metastable ferroelectric phase, and the charge increases rapidly; when the external electric field is removed, the ferroelectric phase returns to the antiferroelectric phase, and the charge decreases rapidly Small to zero. Here, _EF is the electric field strength threshold required to transform the antiferroelectric phase into a ferroelectric phase, and E _B is the electric field strength threshold to prevent the ferroelectric phase from returning to the antiferroelectric phase.

。根据单位体积的贮能量计算公式 $W=\underset{0}{\overset{E_b}{\&Integral;}}\mathrm{EdD},$ 反铁电陶瓷储存的电能量为I+II+III区域，释放出的电能量II+III区域，线性电介质所储存和释放的电能量为III区域。该图说明在施加同样的电场强度时反铁电陶瓷储存和释放的电能量远大于线性电介质的能量。In Figure 2, the abscissa is the applied electric field strength E, and the ordinate is the amount of charge on the ceramic unit electrode area

. According to the calculation formula of energy storage per unit volume $W=\underset{0}{\overset{{\mathrm{E.}}_b}{\&Integral;}}\mathrm{EdD},$ The electric energy stored by the antiferroelectric ceramic is the I+II+III region, the released electric energy is the II+III region, and the electric energy stored and released by the linear dielectric is the III region. This figure shows that when the same electric field strength is applied, the electric energy stored and released by antiferroelectric ceramics is much greater than that of linear dielectrics.

In Figure 3, the abscissa is the applied electric field strength E, and the ordinate is the differential relative permittivity of ceramics ${\mathrm{\&epsiv;}}_r^d=\frac{1}{{\mathrm{\&epsiv;}}_o}\frac{\&PartialD;P}{\&PartialD;\mathrm{E.}},$ where _εo is the vacuum permittivity and P is the polarization. This figure shows that the dielectric coefficient of the antiferroelectric capacitor ceramics of the present invention increases when the voltage increases, and a maximum value is formed at the switching electric field intensity that induces antiferroelectric-ferroelectric phase transition.

In Fig. 4, the abscissa is the applied electric field strength E, and the ordinate is the polarization P of the ceramic. This figure shows that the polarization intensity of the antiferroelectric capacitor ceramics of the present invention increases sharply after the electric field strength is greater than the forward switching electric field, and correspondingly the stored energy increases. When the electric field intensity is lower than the reverse conversion electric field intensity, the polarization intensity decreases rapidly, and electric energy is released correspondingly.

Fig. 5 and Fig. 6 are the discharge curves of the antiferroelectric ceramic of the present invention as a high energy storage capacitor in resistance, capacitance and inductance loads and an application example as a pulse voltage regulator.

Below in conjunction with accompanying drawing and the embodiment that inventor provides, the present invention is described in further detail. The formula scope of invention, all can reach object of the present invention.

Detailed ways

Embodiment 1: Nonlinear relationship of polarization intensity of antiferroelectric ceramics of the present invention as a function of applied voltage

Partially replace the positive divalent lead element in the lead zirconate titanate compound with positive trivalent lanthanum, and partially replace the positive tetravalent zirconium element in the lead zirconate titanate compound with positive tetravalent tin element to form lanthanum-modified zirconium tin lead titanate solid solution, the chemical composition expression of the antiferroelectric ceramic capacitor of the present invention is (Pb _0.925 La _0.05 )[(Zr _0.70 Sn _0.30 ) _0.85 Ti _0.15 ]O ₃ . The oxides PbO, ZrO ₂ , SnO ₂ , TiO ₂ , La ₂ O ₃ containing the above elements are weighed and mixed according to the molar ratio of the elements, after ball milling, pre-calcination, secondary ball milling, granulation, compaction, plastic discharge, The sintering and annealing processes make bulk antiferroelectric ceramics. Among them: in the ball milling process, the raw materials are ground to an average particle size of about 400 nanometers; in the calcining process, the ground powder is pressed into a green body with a thickness of 15mm and a diameter of 50mm and put in an alumina crucible. Pre-fired in electric furnace. The pre-firing program is that the temperature rise rate is 60 minutes/hour and heated to 850°C, and then it is naturally cooled to room temperature with the furnace at 850°C for 2 hours. During the pre-fired heating, the alumina crucible should be covered and sealed to prevent the PbO in the green body from distributing, and the pre-fired green body will form a perovskite crystal phase through a chemical synthesis reaction; in the ceramic sintering process, the sintering program is that the heating rate is Heating to 1280°C at 120 minutes/hour, keeping the temperature at 1280°C for 3 hours, then cooling to room temperature naturally with the furnace. In the ceramic sintering, the double-layer alumina crucible is reversed and sealed to prevent the distribution of PbO in the green body, and a PbZrO3 sheet should be placed in the alumina crucible to maintain the PbO atmosphere. The length shrinkage rate of the fired ceramic is 12%, the average grain size is 4 microns, and it is a perovskite crystal phase.

The antiferroelectric ceramics are cut into square pieces with a thickness of 1.00mm and a width of 30.00mm, polished and cleaned, and then silver-fired to prepare the metal electrode surface. Then place it in transformer insulating oil and heat it to 220°C for 0.5 hours, then cool it down naturally for thermal cleaning. During the thermal cleaning process, use a metal sheet to connect the ceramic upper electrode surface and the lower electrode surface. After heat cleaning treatment, a sinusoidal alternating voltage with an electric field strength of 5kV/mm is applied to the ceramics for 10 cycles for electrical aging treatment. After the above-mentioned processed ceramic welding wire is packaged, it can be used as an antiferroelectric ceramic capacitor.

Embodiment 2: the embodiment of antiferroelectric ceramics of the present invention as discharge capacitor

Use positive trivalent lanthanum and positive divalent strontium to partially replace the positive divalent lead element in the lead zirconate titanate compound, and use positive tetravalent tin elements to partially replace the positive tetravalent zirconium element in the positive zirconate lead titanate compound to form a common combination of lanthanum and strontium. Doping modified lead zirconium tin titanate solid solution to obtain the chemical composition expression of the antiferroelectric ceramic capacitor of the present invention is (Pb _0.91 La _0.02 Sr _0.06 )(Zr _0.54 Sn _0.30 Ti _0.16 )O ₃ . The antiferroelectric ceramics and capacitors were obtained under conditions similar to those of the ceramics and capacitors in Example 1. The antiferroelectric ceramics were discs with a thickness of 0.060 cm and an area of 7.80 cm. After applying a DC voltage with an amplitude of 3kV to charge, then discharge under short-circuit conditions. The discharge current is damped and oscillated, and the maximum current peak reaches 1500 amperes.

Embodiment 3: the embodiment of antiferroelectric ceramics of the present invention as discharge capacitor

The difference between this example and Example 2 is that the positive divalent lead element in the lead zirconate titanate compound is partially replaced with the positive divalent barium to form a co-doped and modified zirconium tin lead titanate solid solution with lanthanum and barium. The chemical composition expression of the antiferroelectric ceramic capacitor of the present invention is (Pb _0.92 La _0.04 Ba _0.02 )(Zr _0.56 Sn _0.40 Ti _0.12 )O ₃ , and the rest are the same as in Example 2.

Embodiment 4: the embodiment of the antiferroelectric ceramic of the present invention as a discharge capacitor

The difference between this example and Example 2 is that the tetravalent zirconium, tin and titanium elements in the lead zirconate titanate compound are partially replaced with niobium with a valence of positive pentavalent to form a niobium-doped lead zirconium tin lead titanate solid solution , the chemical composition expression of the antiferroelectric ceramic capacitor of the present invention is (Pb _0.99 Nb _0.02 )[(Zr _0.60 Sn _0.40 ) _0.95 Ti _0.05 ] _0.98 O ₃ , and the rest are the same as in Example 2.

Embodiment 5: the embodiment of the antiferroelectric ceramic of the present invention as a discharge capacitor

The difference between this example and Example 2 is that a trace chemical element bismuth is added to the material, and the chemical composition formula of its solid solution is written as (Pb _0.97 La _0.02 )[(Zr _0.60 Sn _0.40 ) _0.90 Ti _0.10 ]O ₃ + 2% wBi, wherein the weight of the sintering element BiCO ₃ is 2% of the weight of PbO, the sintering temperature is 1160 ° C, and the rest are the same as in Example 2.

Embodiment 6: The embodiment of the antiferroelectric ceramic of the present invention as a pulse voltage regulator

The antiferroelectric ceramics and capacitors were obtained by adopting the same conditions as those in the manufacturing process of the ceramics and capacitors in Example 2. The output of the pulse power supply is a rectangular electrical pulse with an upsurge on the leading edge. Connecting a piece of antiferroelectric ceramics with a thickness of 0.10cm and an area of 0.50cm in parallel in the circuit can eliminate the overshoot peak without reducing the voltage of the rectangular electric pulse.

The present invention partially replaces the zirconium element in the lead zirconate titanate compound with the tin element, and partially replaces the lead element in the lead zirconate titanate compound with the lanthanum, strontium and barium elements, so that the conversion electric field strength for inducing the antiferroelectric-ferroelectric phase transition And the phase transition temperature can be adjusted in a wider range, which can reduce the strain and hysteresis width generated during phase transition, so that antiferroelectric ceramic capacitors can be used in different operating voltage ranges, and reduce the dielectric of antiferroelectric ceramics Loss, improve electrical breakdown strength and use times. The antiferroelectric capacitor ceramic material of the present invention solves the defect that the dielectric coefficient of ferroelectric ceramics decreases with the electric field strength at high voltage, solves the defects of low dielectric coefficient and poor temperature stability of liquid and organic dielectrics, and provides a kind of Dielectric nonlinear capacitor materials with high energy storage density and high output power. The preparation process of the ceramic material for the antiferroelectric capacitor of the present invention makes the microstructure of the antiferroelectric ceramic dense, stable in performance and high in electric breakdown resistance. The production method is consistent with the traditional electronic ceramic preparation method, and can be used as an industrial production method with simple process and low cost.

The energy storage density of the antiferroelectric ceramic capacitor material of the invention can reach 1 joule/cubic centimeter, the discharge pulse power is more than 1 megawatt/cubic centimeter, and can be used in a temperature range above -40°C. Antiferroelectric ceramic capacitors can be made into monolithic ceramic capacitors, and can also be made into multilayer composite ceramic capacitors by stacking multiple ceramic pieces. The charging voltage and discharging voltage of antiferroelectric ceramic capacitors can be set by adjusting the chemical composition of the material, and can also be adjusted by changing the thickness of the ceramic sheet or the circuit series and parallel connection of multiple capacitor components.

Claims (4)

1. antiferroelectric ceramic capacitor material, it is characterized in that: this material adopts valence to be positive tetravalent tin element partial substitution zirconate lead titanate compound Pb (Zr, Ti) _O In positive tetravalent zirconium element, with positive trivalent lanthanum The element partially replaces the positive divalent lead element in Pb(Zr,Ti)O ₃ to form a multi-component solid solution with lead vacancies; the chemical composition formula of its charge and valence balance is written as (Pb _1-3z/2 La _z )[( Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , wherein the variation of x is between 0.06-0.20, the variation of y is between 0.20-0.40, and the variation of z is between 0.02-0.08. 2. Antiferroelectric ceramic capacitor material is characterized in that: the material adopts valence as positive divalent element strontium or barium element to replace the positive divalent lead element in Pb(Zr, Ti) _O3 , and its charge and valence balance chemical composition formula Written as [(Pb _1-w B _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where B represents a chemical element equivalent to replace Pb element; 1) When B takes Sr element, the chemical formula is written as [(Pb _1-w Sr _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where the change of x The amount is between 0.04-0.18, the variation of y is between 0.20-0.40, the variation of z is between 0.02-0.10, and the variation of w is between 0.02-0.06; 2) When B takes Ba element, the chemical formula is written as [(Pb _1-w Ba _w ) _1-3z/2 La _z ][(Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ , where the change of x The amount is between 0.04-0.18, the variation of y is between 0.20-0.40, the variation of z is between 0.02-0.10, and the variation of w is between 0.02-0.12. 3. according to claim 1 and 2 described antiferroelectric ceramic capacitor materials, it is characterized in that: in the material, add the trace chemical element of aiding firing, the chemical composition formula writing of its solid solution (Pb _1-3z/2 La _z )[ (Zr _1-y Sn _y ) _1-x Ti _x ]O ₃ +C, wherein C represents bismuth, nickel or copper, and the molar atomic variation of C is 1%-2%. 4. the manufacturing process of antiferroelectric capacitor ceramic material is characterized in that, adopts conventional electronic ceramic preparation process, the antiferroelectric ceramic capacitor material formula of claim 1 or 2 or 3 is weighed, ball milled, pre-fired, sintered and Optimizing the process conditions of the seasoning process is characterized in that it comprises the following steps: 1) In the ball milling process, the raw materials are mixed evenly and the particle size is about 400 nanometers; 2) In the pre-firing process, the powder is pressed into a block and placed in an alumina crucible, sealed and heated to 750-860°C for 1-2 hours, so that the mechanically mixed raw materials undergo a chemical synthesis reaction to form a perovskite crystal phase; 3) In the sintering process, the green body is placed in an alumina crucible, sealed and heated to 1100-1300°C for 2-3 hours, and the ceramics are sintered in an atmosphere rich in lead and oxygen, and the cooling rate is slow; 4) In the aging process, the obtained antiferroelectric ceramics are cut, polished, and cleaned to make metal electrodes with excellent electrical conductivity, and then aging treatment is performed; the aging treatment method is: in the room temperature environment, the ceramic positive and negative electrodes An alternating voltage with an electric field strength 1.5 times the forward conversion electric field strength of the antiferroelectric ceramics is applied between the surfaces and repeated for 5-10 cycles.

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