Piezoelectric ceramic material, method for producing the same, and piezoelectric device

Abstract

The application belongs to the technical field of electronic ceramics and components, and more particularly to a piezoelectric ceramic material, a preparation method thereof and a piezoelectric device. The chemical composition of the piezoelectric ceramic material of the application accords with a general formula: xPMN-0.2PNN-(0.8-x)PZT+ywt% low-melting-point sintering additives. The ceramic component prepared by the application can be sintered to be dense under low-temperature conditions of 950 DEG C, and simultaneously has excellent piezoelectric performance. E =2kV / mm, the piezoelectric coefficient d33 d 33 * is up to 858 pm / V, the piezoelectric coefficient d33 d 33 * changes at a rate of less than 5%. The fatigue test of the device made of the piezoelectric material shows that the displacement output still maintains excellent stability at a change rate of less than 5% when the working frequency is up to 500 million times under the excitation of a 50 Hz, 100 V triangular wave voltage.

Description

Technical Field

[0001] This application belongs to the field of electronic ceramics and components technology, and more specifically, relates to a piezoelectric ceramic material and its preparation method, and a piezoelectric device. Background Technology

[0002] Piezoelectric ceramics are a class of materials that possess both positive and negative piezoelectric effects, enabling the coupling and conversion between mechanical and electrical energy. They are fundamental electronic materials and components in the industrial field, widely used in sensors, transducers, and actuators, and are core basic materials for applications in optics, mechanics, electronics, and biomedicine.

[0003] There are many types of piezoelectric ceramics, classified by crystal structure as perovskite, bismuth layered, and tungsten bronze, among which perovskite is the most widely used. ABO3 perovskites include simple perovskites such as PZT, BT, KNN, and BNT, as well as composite perovskite structures such as PMN, PZN, and PNN. Currently, PZT-based piezoelectric ceramics remain the most widely used piezoelectric material. Due to their excellent piezoelectric properties and good manufacturing characteristics, a series of commercial grades have been developed, covering "soft," "medium," and "hard" properties.

[0004] With increasingly demanding application requirements, higher performance standards are being placed on basic piezoelectric ceramics, necessitating further modification of PZT to meet the specifications of device applications. Traditional binary PZT piezoelectric ceramics, composed of the ferroelectric phase PT and the antiferroelectric phase PZ, form a quasi-isomorphic phase boundary (MPB) around the Zr / Ti ratio of approximately 52 / 48. This MPB facilitates domain polarization reversal, resulting in high piezoelectric properties. For example, the typical PZT-5H grade piezoelectric ceramic exhibits a piezoelectric coefficient... d 33 * ~590 pC / N, Curie temperature T c ~193℃, but it is difficult to meet the requirements of some current devices for higher voltage coefficients and operating temperatures.

[0005] When piezoelectric ceramics operate based on the inverse piezoelectric effect, they generate high-frequency vibrations under the drive of an electric field. Due to dielectric losses, they generate heat, and temperature changes alter their piezoelectric properties, affecting the stable operation of the device. Simultaneously, the devices require a high operating life, typically reaching hundreds of millions of cycles. Therefore, there is an urgent need to develop high-performance piezoelectric ceramics that are stable in terms of temperature and fatigue life. Jia-Jun Zhou et al. (J Mater Sci: Mater Electron, 2014, 25:2540-2545) studied the temperature stability of 0.5PNN-0.5PZT, finding that from room temperature to 120℃, the piezoelectric coefficient d... 33 *The change rate is <10%, but the ceramic sintering temperature is very high, ~1250℃. Zhuo Xing et al. (Journal of Materiomics, 2026, doi: 10.1016 / j.jmat.2026.101234) developed PNN-PZT piezoelectric ceramics, with a piezoelectric coefficient change rate of ±20% in the range of 30-90℃. In addition, as the device's operating time and number of cycles increase, the vibration displacement of the piezoelectric ceramic begins to deteriorate, and the performance decreases. Piezoelectric ceramics with long-life and stable output characteristics are crucial for device applications, but there is still relatively little basic research on ceramics in this area. Methee Promsawat et al. (J Eur Ceram Soc 37 (2017) 2047–2055) studied the bipolar fatigue of PZT, but the fatigue life was only 10. 6 However, the number of test cycles is far from sufficient; moreover, the fatigue characteristics change significantly with temperature, which is difficult to meet the requirements of applications. Abid Hussain et al. (J Mater Sci: Mater Electron (2017) 28:14298–14307) studied the fatigue of Sb-doped PMN-PT ceramics, which have a low piezoelectric coefficient. 33 * ~647 pm / V, reported electrical fatigue up to 10 7 While the secondary polarization intensity can still maintain good performance, the electric field strength in lifetime testing is relatively low (E~1kV / mm), and the parameters studied are not key performance indicators. The current challenges of limited testing cycles and poor stability in piezoelectric ceramics are precisely the problems this invention aims to solve.

[0006] In addition, when piezoelectric ceramics are used, a layer of metal electrodes is printed on the surface. The traditional sintering temperature of PZT is ~1200℃. At such a high temperature, the content of precious metals such as Pd or Pt in the electrodes will increase significantly during co-firing, which will drastically increase the cost of electrodes and components. Therefore, developing low-temperature sintered PZT ceramics can effectively reduce electrode costs and sintering energy consumption, which is especially important at present when the price of precious metals is soaring. Regarding the low-temperature sintering of PZT, some research has been reported. SinanDursun et al. (Sensors and Actuators A 286 (2019) 4–13) studied the low-temperature sintered PNN-PMW-PZT material at a sintering temperature of 1000℃. Under the test conditions of 2kV / mm, the piezoelectric coefficient was 645pm / V, and the performance still needs to be further improved. Chenming Gu et al. (Ceram Int 51 (2025) 58902–58910) studied 0.3 Pb(Ni 1 / 3 Nb 2 / 3The O3-0.7Pb(Zr, Ti)O3-LiNbO3-Li2CO3 system, with a sintering temperature below 1150°C, under test conditions of 2kV / mm, d 33 * The piezoelectric properties are unsatisfactory around 700 pm / V. Further research is needed to determine how to maintain high piezoelectric performance while achieving low-temperature sintering. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this application is to provide a low-temperature sintered piezoelectric ceramic with high piezoelectric performance and stability, and its preparation method, for application in the fields of sensors, transducers, and actuators. This aims to solve the technical problems of excessively high sintering temperature and the need to improve the stability and piezoelectric performance of existing piezoelectric ceramics.

[0008] To achieve the above objectives, in a first aspect, this application provides a piezoelectric ceramic material comprising a main component and auxiliary components, wherein the expression for the main component is xPbMg 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 O3, where 0.1 ≤ x ≤0.4; the auxiliary component is a sintering aid, and the sintering temperature of the piezoelectric ceramic material is less than or equal to 1000℃.

[0009] Preferably, 0.15≤ x ≤0.35; and the sintering temperature of the piezoelectric ceramic material is less than or equal to 950℃.

[0010] Preferably, the sintering aid accounts for less than 2% of the mass of the main component, and more preferably 0.5%-1.5%.

[0011] Preferably, the sintering aid is one or more of LiF, Bi2O3, CuO and ZnO.

[0012] More preferably, the sintering aid is at least two of LiF, Bi2O3, CuO and ZnO.

[0013] According to another aspect of the present invention, a method for preparing the piezoelectric ceramic material is provided, comprising the following steps: S1. Using PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the expression xPbMg 1 / 3 Nb 2 / 3 O3-0.2PbNi1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 The atomic ratio of O3 is used to formulate the ingredients, followed by ball milling and mixing. After ball milling, the mixture is dried and sieved at 800-900 rpm. o Sintering at C for 1.5-2.5 hours yields the main component synthetic powder. S2. After mixing the main component powder obtained in step S1 with the sintering aid, the mixture is ball-milled again and dried to obtain piezoelectric ceramic raw material powder. S3. After sieving the piezoelectric ceramic raw material powder obtained in step S2, granulate it and mold it to obtain a green sheet. S4. The green sheet obtained in step S3 is first heated to degrease, and then covered with the main component powder obtained in step S1, at 900-1000℃. o Sintering at C for 1.5-2.5 hours yields ceramic sheets; S5. Polish the ceramic sheet obtained in step S4, silver-coated its surface, silver-burning, and DC polarization treatment to obtain the piezoelectric ceramic material.

[0014] Preferably, in step S4, the green sheet obtained in step S3 is degreased at 450-600℃; Step S4 is in 940-960 o Sintering at C for 1.5-2.5 hours yields ceramic sheets.

[0015] According to another aspect of the invention, a piezoelectric device is provided, comprising the aforementioned piezoelectric ceramic material.

[0016] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art: This invention relates to the quaternary xPbMg system 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 O3-based piezoelectric ceramics are piezoelectric materials with high temperature stability and long lifespan. Furthermore, by adding low-melting-point sintering aids, low-temperature sintering is achieved, which is beneficial for reducing the cost of components. The ceramic material of this invention can be sintered densely at a low temperature of 950°C while exhibiting excellent piezoelectric properties. The preferred embodiment of the ceramic material... E When tested with a DC electric field of 2kV / mm, the piezoelectric coefficient d 33 *The piezoelectric coefficient reaches as high as 858 pm / V; temperature stability and fatigue life studies of this piezoelectric material revealed that, under conditions ranging from room temperature to 100°C, the piezoelectric coefficient is... d 33 * The rate of change is less than 5%; under 50Hz, 100V triangular wave voltage excitation, the displacement output maintains excellent stability even after 500 million cycles, with a rate of change of less than 5%. Attached Figure Description

[0017] Figure 1 This is the temperature-varying SE test curve of the piezoelectric ceramic prepared in Example 2 of this application; Figure 2 This is the XRD pattern of the piezoelectric ceramic prepared in Example 4 of this application; Figure 3 This is a SEM image of the high-temperature sintered piezoelectric ceramic from Experiment Example 2 of this application; Figure 4 This is a SEM image of the low-temperature sintered piezoelectric ceramic of Embodiment 4 of this application; Figure 5 The fatigue life test of the device prepared based on the piezoelectric ceramic material in Example 2 is as follows. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0019] This invention provides a piezoelectric ceramic material comprising a main component and auxiliary components, wherein the expression for the main component is xPbMg. 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 O3, where 0.1 ≤ x ≤0.4, preferably 0.15≤ x ≤0.35, preferably 0.15≤ x ≤0.25; the auxiliary component is a sintering aid, and the sintering temperature of the piezoelectric ceramic material is less than or equal to 1000℃, more preferably less than or equal to 950℃.

[0020] In some embodiments, the sintering aid accounts for less than 2% of the mass of the main component, more preferably 0.5%-1.5%. The sintering aid is one or more of LiF, Bi2O3, CuO and ZnO, more preferably, the sintering aid is at least two of LiF, Bi2O3, CuO and ZnO.

[0021] The present invention also provides a method for preparing the piezoelectric ceramic material, comprising the following steps: S1. Using PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the expression xPbMg 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 The atomic ratio of O3 is used to formulate the ingredients, followed by ball milling and mixing. After ball milling, the mixture is dried and sieved at 800-900 rpm. o Sintering at C for 1.5-2.5 hours yields the main component synthetic powder. S2. After mixing the main component powder obtained in step S1 with the sintering aid, the mixture is ball-milled again and dried to obtain piezoelectric ceramic raw material powder. S3. After sieving the piezoelectric ceramic raw material powder obtained in step S2, granulate it and mold it to obtain a green sheet. S4. The green sheet obtained in step S3 is first heated to degrease, and then covered with the main component powder obtained in step S1, at 900-1000℃. o Sintering at C for 1.5-2.5 hours yields ceramic sheets; S5. Polish the ceramic sheet obtained in step S4, silver-coated its surface, silver-burning, and DC polarization treatment to obtain the piezoelectric ceramic material.

[0022] In some embodiments, during ball milling in steps S1 and S2, alcohol is used as the milling medium, and ZrO2 milling balls are employed. The sieving in step S1 involves passing the material through an 80-mesh sieve, and the undersize material is collected. The sieving in step S3 involves passing the material through a 120-mesh sieve, and the undersize material is collected. In step S3, the piezoelectric ceramic raw material powder obtained in step S2 is sieved and then added to a PVA aqueous solution for granulation.

[0023] In some embodiments, in step S4, the green sheet obtained in step S3 is first degreased at 450-600°C; preferably, step S4 is performed at 940-960°C. o Sintering at C for 1.5-2.5 hours yields ceramic sheets.

[0024] The present invention also provides a piezoelectric device comprising the piezoelectric ceramic material described herein.

[0025] This invention provides a low-temperature sintered piezoelectric ceramic with high voltage and high stability (temperature, fatigue) and its preparation method, which shows great performance and cost advantages in device applications and can be widely used in various piezoelectric devices such as sensors, actuators, transducers, etc.

[0026] In this invention, PbMg 1 / 3 Nb 2 / 3 O3 is abbreviated as PMN, PbNi 1 / 3 Nb 2 / 3 O3 is abbreviated as PNN, PbZr 0.43 Ti 0.57 O3 is abbreviated as PZT. The chemical composition of the novel PZT-based piezoelectric ceramic material of this invention conforms to the general formula: xPMN - 0.2PNN - (0.8-x)PZT + ywt% low-melting-point sintering aid, 0.1≤ x ≤0.4, y<2. The low-melting-point material is one or more of LiF, Bi₂O₃, CuO, and ZnO, synthesized using traditional piezoelectric ceramic preparation processes. With adjustments to the composition and optimization of the low-melting-point sintering aids, the ceramic element produced by this invention can be sintered densely at a low temperature of 950℃, while also possessing excellent piezoelectric properties. E When tested with a DC electric field of 2kV / mm, the piezoelectric coefficient d 33 * Up to 858 pm / V, piezoelectric coefficient under conditions ranging from room temperature to 100°C. d 33 * The rate of change is less than 5%. Fatigue testing of devices made of this piezoelectric material revealed that, under 50Hz, 100V triangular wave voltage excitation, the displacement output maintained excellent stability even after 500 million cycles, with a rate of change of less than 5%.

[0027] The embodiments of the present invention are implemented under the premise of the technical solution of the present invention, and detailed implementation methods and processes are given. However, the protection scope of the present invention is not limited to the following embodiments. The process parameters in the following embodiments that do not specify specific conditions are generally in accordance with conventional conditions.

[0028] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0029] Example 1 This embodiment uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the chemical formula 0.2PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3Nb 2 / 3 O3-0.6PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, added with a low-temperature sintering aid (0.3%wtLiF + 0.4%wtBi2O3 + 0.3%wtZnO), and ball-milled for 24 hours. After drying, it was passed through a 120-mesh sieve, and then granulated with 2wt% PVA aqueous solution. It was then molded and heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 950°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0030] Example 2 This embodiment uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the chemical formula 0.2PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.6PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, and a low-temperature sintering aid (0.3%wtLiF + 0.4%wtBi2O3 + 0.4%wtCuO) was added. The powder was ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 950°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0031] When testing the SE curve characteristics at varying temperatures ( d 33 * = S max / E maxStarting at room temperature (25°C), a curve was tested every 15°C until 100°C. Subsequently, based on this piezoelectric ceramic powder, organic matter was added to form a slurry system. Through typical LTCC manufacturing techniques such as casting, printing, lamination, and co-firing, piezoelectric devices were fabricated. During fatigue testing, the peak voltage was 100V, a triangular wave, and the frequency was 50Hz. Voltage-displacement performance was monitored every 100 million cycles.

[0032] Figure 1 The temperature-induced strain (SE) curves of the piezoelectric ceramic prepared in Example 2 are shown, with a set of curves measured every 15°C. It can be seen that the inverse piezoelectric coefficient d of this ceramic system is... 33 * It exhibits very large displacement and excellent temperature stability. Under an electric field of 2kV / mm, the ceramic can output a displacement of 0.17%. d 33 * ~858pm / V; and the displacement change rate is ~3% in the range of room temperature to 100℃, which is significantly better than existing research reports. Figure 5 For fatigue life testing of the device prepared based on the piezoelectric ceramic material in Example 2, a curve was tested every 100 million cycles. It can be seen that as the number of cycles increases up to 500 million, the performance remains stable and reliable with a change of less than 5%, meeting the device's working life requirements.

[0033] Example 3 This embodiment uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the chemical formula 0.2PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.6PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, and a low-temperature sintering aid (0.5% wt LiF + 0.7% wt CuO) was added. The powder was ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. Granulation was then carried out with 2 wt% PVA aqueous solution, and the granules were molded and heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 950°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0034] Example 4 This embodiment uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5 and other raw materials, according to the chemical formula 0.2PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.6PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, and a low-temperature sintering aid (0.4%wtBi2O3 + 0.2%wtZnO + 0.3%wtCuO) was added. The powder was ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 950°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0035] Figure 2 XRD pattern of the piezoelectric ceramic prepared in Example 4 (2θ angle range 20-70°) o As can be seen from the figure, after adding the low-temperature sintering aid, no impurity phases were generated in the material system, and it still maintained a pure perovskite crystal phase structure. Figure 4 The SEM image shows that the microstructure of the piezoelectric ceramic sintered at low temperature is dense with no obvious pores and an average grain size of ~2μm.

[0036] Example 5 This embodiment uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the chemical formula 0.2PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.6PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, and a low-temperature sintering aid (0.9% wtLiF) was added. The powder was ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. Granulation was then carried out with 2 wt% PVA aqueous solution, and the granules were molded and heated at 600 °C. oAfter holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 950°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0037] Experimental Example 1 This experimental example uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5 and other raw materials, according to the chemical formula 0.15PbMg 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-0.65PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. A 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 1250°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0038] Experiment Example 2 This experimental example uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5 and other raw materials, according to the chemical formula 0.25PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.55PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. A 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 1250°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0039] Figure 3 The image shows a SEM image of the high-temperature sintered piezoelectric ceramic in this experiment. It can be seen that the internal structure of the ceramic is dense, with an average grain size of ~4μm.

[0040] Experimental Example 3 This experimental example uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5 and other raw materials, according to the chemical formula 0.35PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.45PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. A 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 1250°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0041] Comparative Example 1 This comparative example uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5, and other raw materials, according to the chemical formula 0.05PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.75PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. A 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 1250°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0042] Comparative Example 2 This comparative example uses analytical grade PbO, MgO, NiO, ZrO2, TiO2, Nb2O5, and other raw materials, according to the chemical formula 0.45PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.35PbZr 0.43 Ti 0.57 After calculating the O3 ratio and weighing the raw materials, they were placed in a nylon ball mill jar and ball-milled for 24 hours using anhydrous ethanol as the medium. The resulting slurry was then dried in an oven, passed through an 80-mesh sieve, and then milled at 850 °C. o Pre-calcined at C for 2 hours. The pre-calcined powder was crushed, ball-milled for 24 hours, dried, and then passed through a 120-mesh sieve. A 2wt% PVA aqueous solution was added for granulation, followed by molding. The granules were then heated at 600°C. o After holding at C for 2 hours to remove the binder, cover the pre-fired powder and then at 1250°C. o Sinter near C for 2 hours. Polish the sintered ceramic sheet, print silver paste on both sides, fire silver electrodes, and then perform DC polarization treatment. After standing for 24 hours, conduct relevant electrical performance tests.

[0043] Comparative Example 3 The rest is the same as in Experiment 2, except that it follows the chemical formula 0.25PbMg 1 / 3 Nb 2 / 3 O3- 0.2PbNi 1 / 3 Nb 2 / 3 O3-0.55PbZr 0.5 Ti 0.5 O3 calculation ratio.

[0044] Table 1: Piezoelectric properties of the piezoelectric ceramic material in this invention

[0045] As shown in Table 1, this invention, through precise control of the composition and optimization of the low-temperature sintering aid system in the PMN-PNN-PZT quaternary piezoelectric ceramic system, achieves the preparation of low-temperature sintered piezoelectric ceramics with high temperature stability and long service life, which is superior to current publicly reported research and meets the application requirements of high-performance piezoelectric devices. Specifically, in Experimental Examples 1 to 3, and Comparative Examples 1 and 2, without the addition of sintering aids, the performance differences of the piezoelectric ceramic materials prepared with different x values ​​were compared. It can be seen that the optimal x value range is 0.15-0.35, and more preferably 0.15-0.25. In Examples 1 to 5, the x value was determined to be 0.2, and the effects of different types and contents of sintering aids on the prepared pressed ceramic materials were compared. It can be seen that the piezoelectric coefficient of the pressed ceramics in Examples 1 to 4 using a composite sintering aid is significantly better than that in Example 5 using only one sintering aid, with the pressed ceramic material prepared in Example 2 exhibiting the best performance. In Comparative Example 3, when the zirconium-titanium ratio of PZT in the main component of Experimental Example 2 was adjusted to 0.5:0.5, the performance of the piezoelectric ceramic material decreased significantly.

[0046] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A piezoelectric ceramic material, characterized in that, It comprises a main component and auxiliary components, wherein the expression for the main component is xPbMg. 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3 Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 O3, where 0.1 ≤ x ≤0.4; the auxiliary component is a sintering aid, and the sintering temperature of the piezoelectric ceramic material is less than or equal to 1000℃.

2. The piezoelectric ceramic material as described in claim 1, characterized in that, 0.15≤ x ≤0.35。 3. The piezoelectric ceramic material as described in claim 1, characterized in that, The sintering aid accounts for less than 2% of the mass of the main component.

4. The piezoelectric ceramic material as described in claim 1, characterized in that, The sintering aid is one or more of LiF, Bi2O3, CuO and ZnO.

5. The piezoelectric ceramic material as described in claim 4, characterized in that, The sintering aid is at least two of LiF, Bi2O3, CuO and ZnO.

6. The method for preparing the piezoelectric ceramic material according to any one of claims 1 to 5, characterized in that, It includes the following steps: S1. Using PbO, MgO, NiO, ZrO2, TiO2, and Nb2O5 as raw materials, according to the expression xPbMg 1 / 3 Nb 2 / 3 O3-0.2PbNi 1 / 3Nb 2 / 3 O3-(0.8-x)PbZr 0.43 Ti 0.57 The atomic ratio of O3 is used to formulate the ingredients, followed by ball milling and mixing. After ball milling, the mixture is dried and sieved at 800-900 rpm. o Sintering at C for 1.5-2.5 hours yields the main component synthetic powder. S2. After mixing the main component powder obtained in step S1 with the sintering aid, the mixture is ball-milled again and dried to obtain piezoelectric ceramic raw material powder. S3. After sieving the piezoelectric ceramic raw material powder obtained in step S2, granulate it and mold it to obtain a green sheet. S4. The green sheet obtained in step S3 is first heated to degrease, and then covered with the main component powder obtained in step S1, at 900-1000℃. o Sintering at C for 1.5-2.5 hours yields ceramic sheets; S5. Polish the ceramic sheet obtained in step S4, silver-coated its surface, silver-burning, and DC polarization treatment to obtain the piezoelectric ceramic material.

7. The preparation method according to claim 6, characterized in that, In steps S1 and S2, during ball milling, alcohol is used as the milling medium, and ZrO2 milling balls are used for ball milling.

8. The preparation method according to claim 6, characterized in that, The sieving process described in step S1 involves passing the material through an 80-mesh sieve and collecting the material that passes through the sieve. The sieving process described in step S3 involves passing the material through a 120-mesh sieve and collecting the material that passes through the sieve.

9. The preparation method according to claim 6, characterized in that, In step S4, the green sheet obtained in step S3 is degreased at 450-600℃.

10. A piezoelectric device, characterized in that, It includes the piezoelectric ceramic material as described in any one of claims 1 to 5.

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