Manufacturing method of novel high-temperature high-performance piezoelectric ceramic material

Abstract

The invention relates to a manufacturing method of a novel high-temperature high-performance piezoelectric ceramic material, the manufacturing method is improved on the basis of a lead zirconate titanate piezoelectric ceramic material, the prepared ceramic material is suitable for a high-temperature environment through doping and process optimization, and the manufacturing method comprises the following steps: burdening and mixing, pre-sintering, secondary ball milling, granulating and forming, glue discharging and sintering. And machining, silver electrode firing and polarization testing are carried out. According to the manufacturing method of the piezoelectric ceramic material, components of the lead zirconate titanate piezoelectric ceramic are optimized, and neodymium oxide is doped into the lead zirconate titanate piezoelectric material, so that the performance of the ceramic is improved. By doping neodymium oxide, volatilization of the piezoelectric ceramic in lead can be effectively inhibited, deformation of the ceramic is reduced, and the piezoelectric ceramic is suitable for application and industrial production. Meanwhile, the Curie temperature of the ceramic is not obviously reduced, so that the preparation of the high-temperature piezoelectric ceramic is realized.

Description

Technical Field

[0001] The invention relates to the technical field of piezoelectric ceramic materials, and in particular to a novel method for manufacturing high-temperature and high-performance piezoelectric ceramic materials. Background Art

[0002] Piezoelectric ceramics are an important functional material that can convert mechanical energy and electrical energy into each other. High-temperature piezoelectric ceramics are in urgent need in high-tech fields such as aerospace, nuclear energy, and oil exploration. Conventional commercial piezoelectric ceramic materials are affected by their Curie temperature and can only work stably at a temperature of ~150°C. Although BiScO3-PbTiO3 materials meet the needs of high-temperature piezoelectric materials in terms of performance, it is difficult to carry out large-scale industrial applications due to the high price of Sc2O3.

[0003] That is, the mainstream commercial high-performance P5 series piezoelectric ceramic materials are difficult to use in high-temperature environments. In view of the need for high-performance piezoelectric ceramics in high-temperature environments, the present invention is designed, that is, a high-performance (d 33 >420pC / N) piezoelectric ceramic materials. In addition, the invention of the application solves the problems of severe volatilization of lead elements and large deformation of ceramics during the sintering process of piezoelectric ceramics, improves the sintering stability of ceramics during the production process, and reduces the production cost of ceramics. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a novel method for manufacturing a high-temperature and high-performance piezoelectric ceramic material. The manufacturing method is improved on the basis of lead zirconate titanate piezoelectric ceramic material, and the obtained ceramic material is suitable for high-temperature environment through doping and process optimization, and comprises the following steps:

[0005] Step S1: Mixing ingredients according to the general formula of a high-power piezoelectric ceramic: Pb(Zr x Ti (1-x) )O3+ymol%Nd2O3, wherein 0.45≤x≤0.65, 0≤y≤10, the raw materials are Pb3O4, TiO2, ZrO2, Nd2O3, the raw materials are weighed according to the stoichiometric ratio of the general formula, the mixed materials are ball-milled, and the ball-milled materials are dried;

[0006] Step S2: pre-calcination, the powder dried in step S1 is passed through a 60-mesh sieve, placed in a crucible, and then pre-calcined in a muffle furnace at a temperature of 810° C. for 2 hours;

[0007] Step S3: secondary ball milling, the powder obtained in step S2 is subjected to secondary ball milling and drying;

[0008] Step S4: Granulation and molding, adding polyethylene solution to the dried powder obtained in step S3 to perform granulation, and the granulated powder is pressed into tablets by a tablet press to form a ceramic embryo;

[0009] Step S5: debinding, placing the embryo body obtained in step S4 into a muffle furnace for debinding, the debinding temperature is 600° C., and the temperature is kept for 2 hours. After cooling to room temperature, the debinded embryo body is obtained;

[0010] Step S6: sintering, placing the debinded embryo obtained in step S5 into a muffle furnace, covering the embryo with zirconium dioxide powder and sintering to obtain a ceramic sheet;

[0011] Step S7: machining, machining the ceramic obtained in step S6 with a grinding and polishing machine, forming it into a designed shape, and cleaning it;

[0012] Step S8: firing the silver electrode, performing step S7 on the surface of the ceramic to be polarized, brushing the silver by screen printing with silver paste, and then firing in a muffle furnace to obtain a silver-coated ceramic sheet;

[0013] Step S9: Polarization test: The ceramic obtained in step S8 is polarized with high-temperature silicone oil, and then cleaned; after cleaning, the ceramic is placed for 24 hours before testing.

[0014] In one embodiment of the present invention, the ball milling process in step S1 takes 12 hours, followed by drying.

[0015] In one embodiment of the present invention, the pre-calcination heating rate in the muffle furnace of step S2 is 3° C. / min, and the powder is coarsely crushed after pre-calcination to obtain pre-calcined powder.

[0016] In one embodiment of the present invention, the secondary ball milling time in step S3 is 24 hours, followed by drying.

[0017] In one embodiment of the present invention, the heating rate of the muffle furnace used in step S5 of debinding is 3° C. / min.

[0018] In one embodiment of the present invention, the sintering temperature rise and fall system for buried firing in step S6 is as follows: heating to 1000°C at a heating rate of 3°C / min, keeping warm for 1 hour, then heating to 1260°C at a heating rate of 2°C / min, keeping warm for 2 hours, and after the insulation, cooling to 800°C at a cooling rate of 4°C / min, and then naturally cooling to room temperature.

[0019] In one embodiment of the present invention, in step S8, the ceramic sheet is fired in a muffle furnace to perform silver firing, wherein the silver firing is performed by heating the ceramic sheet to 800° C. at a rate of 3° C. / min and maintaining the temperature at the temperature for 30 min.

[0020] The above technical solution of the present invention has the following advantages over the prior art: The piezoelectric ceramic material manufacturing method described in the present invention optimizes the components of lead zirconate titanate piezoelectric ceramics and improves the performance of the ceramics by adding neodymium oxide to the lead zirconate titanate piezoelectric material. The addition of neodymium oxide can effectively inhibit the volatilization of lead elements in piezoelectric ceramics, reduce the deformation of ceramics, and is suitable for application and industrial production. At the same time, the Curie temperature of the ceramics does not decrease significantly, thereby realizing the preparation of high-temperature piezoelectric ceramics. The piezoelectric ceramics in Example 2 of the ceramic system maintain good stability at 230°C, which is similar to the d 33 In contrast, the fluctuation is less than 7%. Compared with the P52 series, which has a d33 attenuation of 60% after annealing at 230°C, this ceramic system has excellent temperature stability and can meet the requirements of stable operation at high temperature scenarios of 230°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0022] Figure 1 It is a line graph of the change in piezoelectric performance after annealing in Example 2 of the novel high-temperature and high-performance piezoelectric ceramic material manufacturing method of the present invention. DETAILED DESCRIPTION

[0023] Embodiment 1

[0024] This embodiment provides a novel method for manufacturing a high-temperature, high-performance piezoelectric ceramic material. The specific high-power lead manganese niobate-lead zirconate titanate piezoelectric ceramic material has a general chemical formula of Pb(Zr x Ti (1-x) )O3+ymol%Nd2O3, wherein x=0.52, 0.53, 0.54. It comprises the following steps:

[0025] S1: Pb3O4, TiO2, ZrO2, and Nd2O3 are weighed and prepared as raw materials. All raw materials are commercially available industrial raw materials. They are then ball-milled and dried. The ball-milling medium is deionized water. The materials are dried after ball-milling for 12 hours.

[0026] S2: The dried powder is mixed with a small amount of deionized water and dry-pressed into a block, which is placed in a crucible and then pre-calcined in a muffle furnace. The pre-calcination heating rate is 3°C / min, the pre-calcination temperature is 800°C, and the pre-calcination holding time is 2 hours. After pre-calcination, the powder is coarsely crushed to obtain pre-calcined powder.

[0027] S3: Secondary ball milling: the powder obtained in S2 is subjected to secondary ball milling for 24 hours, followed by drying.

[0028] S4: Granulation and molding, add 9wt% concentration and 8% polyvinyl alcohol solution to S3, mix and grind, sieve with a mesh size of 80. The powder obtained in step S3 is pressed into tablets by a tablet press to form a ceramic embryo.

[0029] S5: debinding. The embryo body obtained in S4 is placed in a muffle furnace for debinding. The debinding temperature is 600° C., the heating rate is 3° C. / min, and the debinding holding time is 2 hours. Then, the debinded embryo body is obtained.

[0030] S6: sintering. The debinded embryo obtained in S5 is placed in a muffle furnace, and the embryo is covered with zirconium dioxide powder for buried firing. The sintering temperature rise and fall system for buried firing is as follows: increase the temperature to 1000°C at a rate of 3°C / min, keep warm for 1 hour, then increase the temperature to 1260°C at a rate of 2°C / min, keep warm for 2 hours, and after the end of the insulation, reduce the temperature to 800°C at a rate of 4°C / min, and then naturally cool to room temperature to obtain a ceramic sheet.

[0031] S7: machining, machining the ceramic obtained in S6 on a grinding and polishing machine, forming it into a designed shape, and cleaning it.

[0032] S8: Silver electrode burning: apply silver electrode on the surface of the ceramic to be polarized in S7, and then place it in a muffle furnace to burn silver. The silver burning steps are: heating up to 800°C at a rate of 3°C / min, and keeping at this temperature for 30 minutes. A silver-coated ceramic sheet is obtained.

[0033] S9: Polarization test, the ceramic obtained in S8 is polarized with silicone oil, the polarization voltage is 4kV / mm, the polarization temperature is 150°C, the polarization is maintained for 20 minutes, and the polarization is completed after cooling to 60°C. After polarization, it is cleaned to obtain a high-power manganese lead niobate-lead zirconate titanate piezoelectric ceramic material. The ceramic is then tested after being placed for 24 hours. The electrical performance test results of Example 1 are shown in the following table:

[0034] Pb(Zr) of Example 1 x Ti 1-x )O3+1mol%Nd2O3 piezoelectric ceramic performance test table

[0035]

[0036] The table shows the performance of the series of piezoelectric ceramics of different components in Example 1. When the doping amount of Nd2O3 is y=0.53, a piezoelectric ceramic material with high performance and high Curie temperature is obtained.

[0037] Embodiment 2

[0038] The chemical formula of a high-power lead manganese niobate-lead zirconate titanate piezoelectric ceramic material in this embodiment is Pb(Zr x Ti(1-x) )O3+ymol%Nd2O3, where x=0.53, y=0.6, 0.8, 1, P52 is the control group. Example 2 confirms the zirconium-titanium ratio of the ceramic, and adjusts the performance of the high-temperature and high-performance piezoelectric ceramic by changing the doping amount of Nd2O3. The other preparation processes of Example 2 are the same as those of Example 1. The electrical performance test results of Example 2 are shown in the table below. The changes in piezoelectric performance after annealing at different temperatures in Example 2 are shown in Figure 1 .

[0039] Pb(Zr) of Example 2 0.53 Ti 0.47 )O3+ymol%Nd2O3 piezoelectric ceramic performance test table

[0040]

[0041] The above table shows that the piezoelectric ceramic properties of the three systems of different components in Example 2 are as follows. Compared with the performance of the high-performance piezoelectric ceramic P52 series that is widely used in commercial applications, the piezoelectric ceramics have higher piezoelectric properties and higher Curie temperatures, wherein the Curie temperature is increased by 40% to 44% compared to the P52 series.

[0042] like Figure 1 As shown in the manufacturing method of this embodiment, the piezoelectric ceramic of Example 2 is annealed at different temperatures under non-in-situ conditions, the annealing process is 3°C / min, and after reaching the expected temperature, it is kept warm for 1 hour, and then cooled to room temperature with the furnace to measure its piezoelectric performance. The piezoelectric ceramic in Example 2 maintains good stability at 230°C, which is comparable to the piezoelectric performance at room temperature. 33 In contrast, the fluctuation is less than 7%. However, the performance of the P52 series is attenuated by more than 60% after annealing at 230°C. Compared with the P52 series ceramics, the piezoelectric ceramic material of Example 2 shows better temperature stability.

[0043] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A novel method for manufacturing a high-temperature, high-performance piezoelectric ceramic material, which is improved on the basis of lead zirconate titanate piezoelectric ceramic material, and the obtained ceramic material is suitable for high-temperature environments through doping and process optimization, and is characterized in that: The steps include: Step S1: Mixing ingredients according to the general formula of a high-power piezoelectric ceramic: Pb(Zr x Ti (1-x) )O3+ymol%Nd2O3, wherein 0.45≤x≤0.65, 0≤y≤10, the raw materials are Pb3O4, TiO2, ZrO2, Nd2O3, the raw materials are weighed according to the stoichiometric ratio of the general formula, the mixed materials are ball-milled, and the ball-milled materials are dried; Step S2: pre-calcination, the powder dried in step S1 is passed through a 60-mesh sieve, placed in a crucible, and then pre-calcined in a muffle furnace at a temperature of 810° C. for 2 hours; Step S3: secondary ball milling, the powder obtained in step S2 is subjected to secondary ball milling and drying; Step S4: Granulation and molding, adding polyethylene solution to the dried powder obtained in step S3 to perform granulation, and the granulated powder is pressed into tablets by a tablet press to form a ceramic embryo; Step S5: debinding, placing the embryo body obtained in step S4 into a muffle furnace for debinding, the debinding temperature is 600° C., and the temperature is kept for 2 hours. After cooling to room temperature, the debinded embryo body is obtained; Step S6: sintering, placing the debinded embryo obtained in step S5 into a muffle furnace, covering the embryo with zirconium dioxide powder and sintering to obtain a ceramic sheet; Step S7: machining, machining the ceramic obtained in step S6 with a grinding and polishing machine, forming it into a designed shape, and cleaning it; Step S8: firing the silver electrode, performing step S7 on the surface of the ceramic to be polarized, brushing the silver by screen printing with silver paste, and then firing in a muffle furnace to obtain a silver-coated ceramic sheet; Step S9: Polarization test: The ceramic obtained in step S8 is polarized with high-temperature silicone oil, and then cleaned; after cleaning, the ceramic is placed for 24 hours before testing.

2. The manufacturing method according to claim 1, characterized in that: The ball milling process in step S1 takes 12 hours, followed by drying.

3. The manufacturing method according to claim 1, characterized in that: The pre-calcination heating rate in the muffle furnace of step S2 is 3° C. / min, and the powder is coarsely crushed after pre-calcination to obtain pre-calcined powder.

4. The manufacturing method according to claim 1, characterized in that: The secondary ball milling time in step S3 is 24 hours, followed by drying.

5. The manufacturing method according to claim 1, characterized in that: The heating rate of the muffle furnace used in step S5 for debinding is 3°C / min.

6. The manufacturing method according to claim 1, characterized in that: The sintering temperature rise and fall system for buried firing in step S6 is: increase the temperature to 1000°C at a rate of 3°C / min, keep it warm for 1 hour, then increase the temperature to 1260°C at a rate of 2°C / min, keep it warm for 2 hours, and after the insulation, reduce the temperature to 800°C at a rate of 4°C / min, and then cool naturally to room temperature.

7. The manufacturing method according to claim 1, characterized in that: In step S8, the ceramic sheet is fired in a muffle furnace to perform silver firing, wherein the silver firing is performed by heating the ceramic sheet to 800° C. at a rate of 3° C. / min and maintaining the temperature at the temperature for 30 min.

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