Piezoelectric ceramic for piezoelectric ceramic fan and method for manufacturing the same

Abstract

The application discloses piezoelectric ceramics for piezoelectric ceramic fans and a preparation method thereof, and the chemical formula of the ceramic material is m%Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 2Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, wherein Me is any one or two of Pr, Ho, Eu, Dy, Nd, Yb, La, Sm, Y, Er and Lu, m% indicates the molar percentage of Me2O3 in (1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 2 Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, 0.05<=x<=0.8, 0.05<=y<=0.8, 0.05<=z<=0.8 and 0.01<=m<=5.0. In the preparation, step-by-step synthesis and two-step sintering are adopted to control the component gradient and proportion, so that the obtained ceramic has small and uniform crystal grains and high density. The Me2O3 rare earth element is added into the multiphase piezoelectric ceramic matrix, and the piezoelectric ceramics exhibit good temperature stability and high piezoelectric coefficient in the range of-60-120 DEG C, and the d 33 is not less than 1695 pC / N. The piezoelectric ceramics have important application in the field of piezoelectric ceramic fans, and are expected to be widely applied in precise positioning systems, medical imaging equipment, sensors and actuators, energy collection and conversion, consumer electronic products and unmanned aerial vehicle and micro air vehicle control fields.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of piezoelectric ceramic materials, and particularly relates to a piezoelectric ceramic for a piezoelectric ceramic fan and a preparation method thereof. BACKGROUND

[0002] A piezoelectric ceramic fan is a device that uses the piezoelectric effect to drive the rotation of fan blades. The piezoelectric effect refers to the phenomenon that certain materials generate an electric voltage when subjected to mechanical stress, and vice versa, when these materials are subjected to an electric voltage, they change in shape or size. In a piezoelectric ceramic fan, this physical phenomenon is used to generate mechanical movement, thereby driving the rotation of the fan. Piezoelectric ceramic fans usually use piezoelectric ceramics as driving elements, when a voltage is applied to the piezoelectric ceramics, it will produce a slight change in shape, and this deformation is converted into the rotation or vibration of the fan blades through a series of mechanical structures, thereby generating air flow. The characteristic of this fan is that there is no part driven by a traditional motor, so it can achieve a very small and light design, and the noise is low when running, which is very suitable for occasions that require a quiet running environment. Piezoelectric ceramic fans are particularly suitable for use in portable electronic devices, such as smartphones, tablets and other devices, due to their small size and can be easily integrated into compact spaces; medical devices, especially devices sensitive to noise, such as hearing aids and other wearable medical devices; precision instruments, in precision instruments where temperature needs to be controlled but space is very limited, piezoelectric fans can provide an effective cooling solution; consumer electronics, in environments that require silent operation, such as small fans or air purifiers in offices or sleep areas.

[0003] Although piezoelectric ceramic fans provide a unique and effective cooling method, their cooling capacity may be lower compared to traditional fans, and piezoelectric ceramic fans usually cannot provide a larger air pressure compared to traditional fans. Therefore, they may not be suitable for applications that require a large amount of air flow. In view of the pain point of piezoelectric ceramic fans, it is necessary to prepare piezoelectric ceramics with high piezoelectric coefficient to solve this problem. Although piezoelectric ceramics are quite stable and durable, they may affect their performance and reliability in high-temperature environments for a long time. Therefore, it is necessary to develop piezoelectric ceramics with good temperature stability and high piezoelectric coefficient as driving elements to solve the durability and air pressure of piezoelectric ceramic fans. SUMMARY

[0004] In view of the defects of low piezoelectric coefficient and poor temperature stability of the existing piezoelectric material, the present application provides a piezoelectric ceramic for piezoelectric ceramic fan and a preparation method thereof, which activates the ferroelectric domain of the piezoelectric ceramic material while maintaining the piezoelectric ceramic material with a relatively high Curie temperature, so that the ferroelectric domain movement becomes easy to perform, and thus they show a relatively high piezoelectric activity under the action of external electric field or mechanical stress, and the property of domain rearrangement makes the piezoelectric ceramic have a relatively high piezoelectric coefficient and good temperature stability.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: a piezoelectric ceramic for a piezoelectric ceramic fan, the chemical formula is m%Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 2 Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, wherein Me is any one or two of Pr, Ho, Eu, Dy, Nd, Yb, La, Sm, Y, Er and Lu, m% refers to the molar percentage of Me2O3 in m%Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 2 Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, 0.05≤x≤0.8, 0.05≤y≤0.8, 0.05≤z≤0.8, 0.01≤m≤5.0, including four main phase solid solutions, the first phase is Pb(Mg 1 / 3Nb 2 / 3 )O3, the second phase is Pb(Zn 1 / 3 Nb 2 / 3 )O3, the third phase is PbTiO3, and the fourth phase is PbZrO3.

[0006] Further, 0.1≤x≤0.6, 0.1≤y≤0.6, 0.1≤z≤0.6, and m=1.5.

[0007] Further, the volume ratio of the first phase, the second phase, the third phase and the fourth phase is 25%, 5%, 30% and 40% respectively.

[0008] The present application also provides a preparation method of the above-mentioned material, comprising the following steps:

[0009] Step 1, ball milling Me2O3 in anhydrous ethanol as a medium to a nanoscale particle size, drying at 80℃ to obtain nanoscale Me2O3 powder;

[0010] Step 2, synthesizing Pb(Mg 1 / 3 Nb2 / 3 )O3 Pb(Zn 1 / 3 Nb 2 / 3 )O3, PbTiO3, PbZrO3;

[0011] Step 3, according to the stoichiometric ratio of m% Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 3 Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, Me2O3 powder, Pb(Mg 1 / 3 Nb 2 / 3 )O3, Pb(Zn 1 / 3 Nb 2 / 3 )O3, PbTiO3, PbZrO3 are mixed, ball-milled in anhydrous ethanol medium with a particle size of nanometer level, dried, and heated in a furnace, and pre-fired at 750-1050°C for 2-6 hours;

[0012] Step 4, the powder obtained after pre-firing in step 3 is granulated with a 5% polyvinyl alcohol aqueous solution by weight concentration, and pressed into a round sheet, and the round sheet after shaping is heated in a furnace, and heat treated at 600-650°C for 2 hours to remove polyvinyl alcohol;

[0013] Step 5, the round sheet after removing polyvinyl alcohol in step 4 is first heated to 1000-1350°C, immediately cooled to 800-1100°C, and heat treated for 2-3 hours to obtain the.

[0014] Further, in step 3, pre-firing is performed at 1020-1050°C for 2-3 hours.

[0015] Further, in step 5, the round sheet after removing PVA in step 4 is first heated to 1200-1300°C, without heat preservation, and then cooled to 1080-1100°C, and heat treated for 3 hours.

[0016] Further, the Me2O3 powder is a nanometer-level Me2O3 powder after wet ball milling and drying.

[0017] Further, the average particle size of Pb(Mg 1 / 3 Nb 2 / 3 )O3 is 100 nm, the average particle size of Pb(Zn 1 / 3 Nb 2 / 3 )O3 is 200 nm, the average particle size of PbTiO3 is 100 nm, and the average particle size of PbZrO3 is 300 nm.

[0018] Further, in steps 3 and 4, the heating rate is 3°C / min, and in step 5, the cooling rate is 10°C / min.

[0019] Further, the obtained d 33 No less than 1695 pC / N.

[0020] Compared with the prior art, the present application has at least the following beneficial effects:

[0021] The present application aims at the lower piezoelectric coefficient of piezoelectric ceramic for piezoelectric ceramic fan, and a proper amount of rare earth element Me is added in the multiphase piezoelectric ceramic matrix to obtain a high stable piezoelectric coefficient. The main principle is to activate the ferroelectric domain by using the rare earth element, to improve the activity of the ferroelectric domain, so that the domain rearrangement under the external electric field is relatively easy, which means that they can realize efficient polarization under a lower electric field, and improve the piezoelectric coefficient of the material. The piezoelectric coefficient of the piezoelectric ceramic of the present application can be as high as 1700 pC / N. At the same time, the piezoelectric coefficient of the ceramic material shows good stability in the range of-60-120℃, and after introducing the rare earth element to activate the ferroelectric domain, the fatigue resistance of the ceramic is greatly enhanced, and the piezoelectric coefficient of the device only decreases by 10% after 100 million cycles. These characteristics show that the piezoelectric ceramic of the present application is expected to be applied in the field of piezoelectric ceramic fan; the present application adopts step-by-step synthesis and two-step sintering, and can control the composition gradient and proportion, so that the ceramic grain obtained is small and uniform, and has high density, which can meet the needs of different applications. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the X-ray diffraction pattern of the ceramic material prepared in Example 1.

[0023] Figure 2 is the scanning electron microscope pattern of the ceramic material prepared in Example 1.

[0024] Figure 3 is the graph of the dielectric constant and dielectric loss of the ceramic material prepared in Example 1 with temperature change.

[0025] Figure 4 is the electric hysteresis loop of the ceramic material prepared in Example 1. DETAILED DESCRIPTION

[0026] The present application will be further described in detail below in combination with the drawings and examples, but the protection scope of the present application is not limited to these examples.

[0027] Example 1

[0028] Step 1. Mill 99.99% pure La2O3 in anhydrous ethanol medium for 12 hours, dry at 150℃ to obtain Me2O3 powder;

[0029] Step 2. Take 122.46 g of Pb304 with a purity of 99.99%, 7.53 g of MgCC with a purity of 99.99%, 47.48 g of Nb205 with a purity of 99.99% into a ball mill jar, and mix them for 12 hours at a volume ratio of raw material mixture, agate ball and anhydrous ethanol of 1:2:4, and then dry them in an oven at 80°C for 10 hours. After drying, the raw material mixture is pressed into a circular green body with a diameter of 60 mm by using a tablet press at 0.1 MPa, and then the circular green body after tablet pressing is placed in a muffle furnace for heat preservation at 800°C for 3 hours, crushed, and Pb(Mg 1 / 3 Nb 2 / 3 )03 with a pure perovskite structure is obtained.

[0030] Take 118.13 g of Pb304 with a purity of 99.99%, 7.01 g of ZnO with a purity of 99.99%, 45.8 g of Nb205 with a purity of 99.99% into a ball mill jar, and mix them for 12 hours at a volume ratio of raw material mixture, agate ball and anhydrous ethanol of 1:2:4, and then dry them in an oven at 80°C for 10 hours. After drying, the raw material mixture is pressed into a circular green body with a diameter of 60 mm by using a tablet press at 0.1 MPa, and then the circular green body after tablet pressing is placed in a muffle furnace for heat preservation at 850°C for 5 hours, crushed, and Pb(Zn 1 / 3 Nb 2 / 3 )03 powder with an average particle size of about 200 nm is obtained.

[0031] Take 130.2 g of Pb304 with a purity of 99.99%, 22.75 g of Ti02 with a purity of 99.99% into a ball mill jar, and mix them for 12 hours at a volume ratio of raw material mixture, agate ball and anhydrous ethanol of 1:2:4, and then dry them in an oven at 80°C for 10 hours. After drying, the raw material mixture is pressed into a circular green body with a diameter of 60 mm by using a tablet press at 0.1 MPa, and then the circular green body after tablet pressing is placed in a muffle furnace for heat preservation at 850°C for 5 hours, crushed, and PbTi03 with an average particle size of about 100 nm is obtained.

[0032] Take 115.88 g of Pb304 with a purity of 99.99%, 31.24 g of Zr02 with a purity of 99.99% into a ball mill jar, and mix them for 12 hours at a volume ratio of raw material mixture, agate ball and anhydrous ethanol of 1:2:4, and then dry them in an oven at 80°C for 10 hours. After drying, the raw material mixture is pressed into a circular green body with a diameter of 60 mm by using a tablet press at 0.1 MPa, and then the circular green body after tablet pressing is placed in a muffle furnace for heat preservation at 850°C for 5 hours, crushed, and PbZr03 with an average particle size of about 300 nm is obtained.

[0033] Step 3. 1.5 at.% La203-0.25 Pb(Mg 1 / 3 Nb2 / 3 O3-0.05Pb(Zn) 1 / 3 Nb 2 / 3 The stoichiometric ratio of O3-0.3PbTiO3-0.4PbZrO3 was determined. The raw materials were weighed and placed in a ball mill jar. The mixture was ball milled for 12 hours according to the volume ratio of the raw material mixture to agate balls and anhydrous ethanol of 1:2:4. After ball milling, the mixture was dried in an oven at 80°C and then pre-fired in a muffle furnace at 1050°C for 2 hours.

[0034] Step 4. Add 2 mL of 5% (w / w) polyvinyl alcohol aqueous solution to the powder obtained after pre-calcination in Step 3 as a binder for granulation. After thorough mixing in a mortar, pass the mixture through a 200-mesh sieve. Press the granulated powder into discs with a thickness of 1.2 mm and a diameter of 12.00 mm under 200 MPa. After pressing, heat the discs at 600℃ for 2 hours to remove polyvinyl alcohol.

[0035] Step 5. After removing the polyvinyl alcohol in Step 4, heat the disc to 1280℃ without holding it at that temperature, then rapidly cool it to 1100℃ and hold it there for 2 hours at a cooling rate of 10℃ / min to obtain the ceramic material 1.5 at.% La₂O₃-0.25Pb(Mg) 1 / 3Nb 2 / 3 O3-0.05Pb(Zn) 1 / 3 Nb 2 / 3 )O3-0.3PbTiO3-0.4PbZrO3.

[0036] The phase structure of the ceramic material prepared in this embodiment was measured using an X-ray diffractometer, such as... Figure 1 As shown, the XRD data indicates that the material is a pure perovskite phase with no impurity phases formed. Figure 2 Scanning electron microscope (SEM) images show that the prepared ceramic is very dense with uniform grain size. Further processing of the ceramic material into a smooth, approximately 1.0 mm thick sheet, with electrodes deposited on both sides, and measurement of the dielectric temperature spectrum and hysteresis loop of the ceramic material were performed. Figure 3 and 4 As shown. By Figure 3 It is evident that the piezoelectric coefficient of this ceramic material exhibits good stability within the temperature range of -60 to 120℃. Figure 4 It is evident that this ceramic material lacks an internal bias electric field. Quasi-static d 33 The tester obtained d after testing. 33 It is 1700pC / N.

[0037] Example 2

[0038] In step 3 of this embodiment, 5.91g of 99.99% pure Yb2O3 is used to replace La2O3 in Example 1, according to the ratio of 1.5 at.% Yb2O3 - 0.1Pb(Mg)1 / 3 Nb 2 / 3 )O3-0.8Pb(Zn 1 / 3 Nb 2 / 3 )O3 -0.05PbTiO3-0.4PbZrO3 stoichiometric ratio, the raw materials were weighed and put into the ball mill jar, and ball-mixed for 10 hours according to the volume ratio of the raw material mixture, agate ball and anhydrous ethanol being 1:2:4. After ball-milling, the mixture was dried in an oven at 80°C, and then put into a muffle furnace for pre-sintering at 750°C for 6 hours.

[0039] Step 4. 2 mL of a 5% by weight polyvinyl alcohol aqueous solution was added dropwise to the powder obtained after pre-sintering in step 3 as a binder for granulation. After mixing in a mortar, the granulated powder was sieved through a 200-mesh sieve; the granulated powder was pressed into a round sheet with a thickness of 1.2 mm and a diameter of 12.00 mm at 200 MPa; and the formed round sheet was treated at 650°C for 2 hours to remove the polyvinyl alcohol.

[0040] Step 5. The round sheet after removal of the polyvinyl alcohol in step 4 was first heated to 1000°C, without holding, and then rapidly cooled to 800°C, and held for 2 hours to obtain a ceramic material 1.5 at.%Yb2O3-0.1Pb(Mg 1 / 3 Nb 2 / 3 )O3-0.8Pb(Zn 1 / 3 Nb 2 / 3 )O3 -0.05PbTiO3-0.05PbZrO3, the quasi-static d 33 After testing by a d 33 was 1705 pC / N.

[0041] Example 3

[0042] In step 3 of this example, 5.05 g of Nd2O3 with a purity of 99.99% was used instead of La2O3 in Example 1, and a ceramic material 1.5 at.%Nd2O3-0.1Pb(Mg 1 / 3 Nb 2 / 3 )O3-0.05Pb(Zn 1 / 3 Nb 2 / 3 )O3 -0.8PbTiO3-0.05PbZrO3 stoichiometric ratio, the raw materials were weighed and put into the ball mill jar, and ball-mixed for 10 hours according to the volume ratio of the raw material mixture, agate ball and anhydrous ethanol being 1:2:4. After ball-milling, the mixture was dried in an oven at 80°C, and then put into a muffle furnace for pre-sintering at 750°C for 6 hours.

[0043] Step 4. Add 2 mL of 5% (w / w) polyvinyl alcohol aqueous solution to the powder obtained after pre-calcination in Step 3 as a binder for granulation. Mix thoroughly in a mortar and pass through a 200-mesh sieve. Press the granulated powder into discs with a thickness of 1.2 mm and a diameter of 12.00 mm under 200 MPa. Heat the discs at 650℃ for 2 hours to remove polyvinyl alcohol.

[0044] Step 5. The discs from Step 4, after removing polyvinyl alcohol, are first heated to 1000℃, then rapidly cooled to 800℃ without holding, and held for 2.5 hours to obtain a ceramic material of 1.5 at.% Nd₂O₃-0.1Pb(Mg)₂. 1 / 3 Nb 2 / 3 O3-0.05Pb(Zn) 1 / 3 Nb 2 / 3 O3-0.8PbTiO3-0.05PbZrO3, quasi-static d 33 The tester obtained d after testing. 33 It is 1695pC / N.

[0045] Example 4

[0046] In this embodiment, 5.28 g of 99.99% pure Eu2O3 replaced La2O3 in Example 1, and the other steps were the same as in Example 1, resulting in a ceramic material of 1.5 at.% Eu2O3-0.05Pb(Mg) 1 / 3 Nb 2 / 3 O3-0.1Pb(Zn) 1 / 3 Nb 2 / 3 O3 -0.05PbTiO3-0.8PbZrO3, quasi-static d 33 The tester obtained d after testing. 33 It is 1996 pC / N.

[0047] Example 5

[0048] In step 3 of this embodiment, the following steps are performed: 1.5 at.% La2O3-0.26Pb(Mg) 1 / 3 Nb 2 / 3 O3-0.04Pb(Zn) 1 / 3Nb 2 / 3 The stoichiometric ratio of La₂O₃-0.29PbTiO₃-0.41PbZrO₃ was determined. Raw materials were weighed and placed in a ball mill jar. The mixture was ball-milled for 12 hours at a volume ratio of raw material mixture to agate balls and anhydrous ethanol of 1:2:4. After ball milling, the mixture was dried in an oven at 80°C and then pre-fired in a muffle furnace at 1000°C for 2 hours. The discs, after removing polyvinyl alcohol, were first heated to 1250°C without holding, then rapidly cooled to 1000°C and held for 2.5 hours to obtain the ceramic material 1.5 at.% La₂O₃-0.26Pb(MgO)₂O₃.1 / 3 Nb 2 / 3 O3-0.04Pb(Zn) 1 / 3 Nb 2 / 3 O3-0.29PbTiO3-0.41PbZrO3, quasi-static d 33 The tester obtained d after testing. 33 It is 1729 pC / N.

[0049] Example 6

[0050] In step 3 of this embodiment, 1.5 at.% Eu2O3-0.4Pb(Mg) 1 / 3 Nb 2 / 3 O3-0.2Pb(Zn) 1 / 3 Nb 2 / 3 The stoichiometric ratio of Eu₂O₃-0.2PbTiO₃-0.2PbZrO₃ was determined. Raw materials were weighed and placed in a ball mill jar. The mixture was ball-milled for 12 hours at a volume ratio of raw material mixture to agate balls and anhydrous ethanol of 1:2:4. After ball milling, the mixture was dried in an oven at 80°C and then pre-fired in a muffle furnace at 950°C for 2 hours. The discs, after removing polyvinyl alcohol, were first heated to 1200°C without holding, then rapidly cooled to 950°C and held for 2.5 hours to obtain the ceramic material 1.5 at.% Eu₂O₃-0.4Pb(MgO)₂. 1 / 3 Nb 2 / 3 O3-0.2Pb(Zn) 1 / 3 Nb 2 / 3 O3-0.2PbTiO3-0.2PbZrO3, quasi-static d 33 The tester obtained d after testing. 33 It is 1906 pC / N.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A piezoelectric ceramic for a piezoelectric ceramic fan, characterized by, m%Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 3 Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, wherein Me is any one or two of Pr, Ho, Eu, Dy, Nd, Yb, La, Sm, Y, Er, and Lu, m% refers to the molar percentage of Me2O3 in m%Me2O3-(1-x-y-z)Pb(Mg 1 / 3 Nb 2 / 3 )O3-xPb(Zn 1 / 3Nb 2 / 3 )O3-yPbTiO3-zPbZrO3, 0.05≤x≤0.8, 0.05≤y≤0.8, 0.05≤z≤0.8, and 0.01≤m≤5.0; including four main phase solid solutions, the first phase being Pb(Mg 1 / 3 Nb 2 / 3 )O3, the second phase being Pb(Zn 1 / 3 Nb 2 / 3 )O3, the third phase being PbTiO3, and the fourth phase being PbZrO3; the obtained d 33 is not less than 1695 pC / N.

2. The piezoelectric ceramic for a piezoelectric ceramic fan according to claim 1, characterized by, 0.1≤x≤0.6, 0.1≤y≤0.6, 0.1≤z≤0.6, m=1.

5.

3. The piezoelectric ceramic for a piezoelectric ceramic fan according to claim 1, characterized by, The first phase, the second phase, the third phase and the fourth phase have a volume ratio of 25%, 5%, 30% and 40% respectively.

4. A method of producing a piezoelectric ceramic for a piezoelectric ceramic fan as claimed in any one of claims 1 to 3, characterized by, The method comprises the following steps: Step 1: Me2O3 is ball milled in anhydrous ethanol as a medium to a nanoscale particle size, and dried at 80°C to obtain a nanoscale Me2O3 powder; Step 2, Pb(Mg 1 / 3 Nb 2 / 3 )O3, Pb(Zn 1 / 3 Nb 2 / 3 )O3, PbTiO3, PbZrO3 were synthesized by high temperature solid phase method respectively; the average particle size of Pb(Mg 1 / 3 Nb 2 / 3 )O3 was 100 nm, the average particle size of Pb(Zn 1 / 3 Nb 2 / 3 )O3 was 200 nm, the average particle size of PbTiO3 was 100 nm, and the average particle size of PbZrO3 was 300 nm; Step 3, according to m%Me2O3-(1-xyz)Pb(Mg) 1 / 3 Nb 2 / 3 )O3- xPb(Zn 1 / 3 Nb 2 / 3 The stoichiometric ratio of Me2O3-yPbTiO3-zPbZrO3 was used to mix Me2O3 powder and Pb(Mg) 1 / 3 Nb 2 / 3 O3, Pb(Zn) 1 / 3 Nb 2 / 3 PbTiO3 and PbZrO3 are mixed and ball-milled to nanoscale particle size using anhydrous ethanol as the medium. After drying, they are pre-calcined in a furnace at 750–1050°C for 2–6 hours. Step 4: The powder obtained after pre-sintering in step 3 is granulated with a 5% weight concentration polyvinyl alcohol aqueous solution, and pressed into a round sheet, and the round sheet after shaping is heated with a furnace, and kept at 600-650°C for 2 hours to remove the polyvinyl alcohol; Step 5: The round sheet after removing the polyvinyl alcohol in step 4 is first heated to 1000-1350°C, immediately cooled to 800-1100°C, and kept for 2-3 hours to obtain the piezoelectric ceramic for the piezoelectric ceramic fan.

5. The method of claim 4, wherein the piezoelectric ceramic is prepared by the steps of: preparing a piezoelectric ceramic slurry; coating the piezoelectric ceramic slurry on a green sheet; and drying the piezoelectric ceramic slurry. In step 3, pre-sintering is performed at 1020-1050°C for 2-3 hours.

6. The method of claim 4, wherein the piezoelectric ceramic is prepared by the steps of: preparing a piezoelectric ceramic slurry; coating the piezoelectric ceramic slurry on a green sheet; and drying the piezoelectric ceramic slurry. In step 5, the round sheet after removing the polyvinyl alcohol in step 4 is first heated to 1200-1300°C, without keeping, and then cooled to 1080-1100°C, and kept for 3 hours.

7. The method of claim 4, wherein the piezoelectric ceramic is prepared by the steps of: preparing a piezoelectric ceramic slurry; coating the piezoelectric ceramic slurry on a green sheet; and drying the piezoelectric ceramic slurry. In steps 3 and 4, the heating rate is 3°C / min, and in step 5, the cooling rate is 10°C / min.

8. The method of claim 4, wherein the piezoelectric ceramic is prepared by the steps of: preparing a piezoelectric ceramic slurry; coating the piezoelectric ceramic slurry on a green sheet; and drying the piezoelectric ceramic slurry. The piezoelectric ceramic obtained has a d 33 not less than 1695 pC / N.

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