Pzt-based piezoelectric ceramic material, method for preparing the same and use thereof

Abstract

The application discloses a PZT-based piezoelectric ceramic material and a preparation method and application thereof. The PZT-based piezoelectric ceramic material comprises lead zirconate titanate and a doping element, wherein the doping element is neodymium and chromium, the doping amount of the neodymium is 2x mol% of the lead zirconate titanate, the doping amount of the chromium is 2ymol% of the lead zirconate titanate, 0.4<=x<=0.8, 0.15<=y<=0.25, the structural formula of the lead zirconate titanate is Pb(Zr z Ti 1‑z )O3, and the lead zirconate titanate is a solid solution formed by lead titanate and lead zirconate. Nd2O3 and Cr2O3 serve as dopants and play the roles of soft doping and hard doping respectively, which is beneficial to the common improvement of piezoelectric performance and temperature stability and can realize the comprehensive performance without degradation under a high-temperature environment. The application effectively solves the technical problem that the existing lead-based piezoelectric ceramic material is difficult to have piezoelectric performance and temperature stability under a high-temperature environment.

Description

Technical Field

[0001] This invention belongs to the field of piezoelectric ceramic technology, specifically relating to a PZT-based piezoelectric ceramic material, its preparation method, and its application. Background Technology

[0002] PZT-based piezoelectric ceramics (the crystal structure of PZT-based piezoelectric ceramics belongs to the typical perovskite ABO3 structure, where the A site is Pb) 2+ B is Zr 4+ With Ti 4+ PZT-based piezoelectric ceramics (solid solutions) are currently the most widely used piezoelectric ceramic materials, possessing excellent electromechanical properties and good temperature stability, making them excellent candidate materials for low- and medium-temperature accelerometers. However, the application of PZT-based piezoelectric ceramics also faces certain challenges. Their Curie temperatures are typically between 250 and 350°C, making it difficult for them to maintain stable operation at high temperatures of 300°C, resulting in a significant decrease in piezoelectric performance or even the loss of the piezoelectric effect. This severely limits their application in the field of high-temperature sensors.

[0003] Currently, doping modification strategies are frequently used to improve the high-temperature performance of piezoelectric materials. Among these, soft dopants can replace the A-site Pb in perovskites. 2+ Lattice distortion is generated, which promotes the movement of electric domains and thus improves the piezoelectric performance at high temperatures. However, it also reduces the stability of the perovskite structure, thereby lowering the Curie temperature and temperature stability of PZT-based piezoelectric ceramics. It is difficult to achieve a simultaneous improvement in piezoelectric performance and the stability of the perovskite structure. Therefore, it is urgent to find a doping strategy that can improve the piezoelectric performance of piezoelectric ceramics at high temperatures while maintaining their temperature stability. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a PZT-based piezoelectric ceramic material. This PZT-based piezoelectric ceramic material is a binary PZT-based piezoelectric ceramic material co-doped with Nd₂O₃ and Cr₂O₃, possessing both piezoelectric properties and temperature stability. Its chemical composition is (x mol% Nd₂O₃ + y mol% Cr₂O₃) + Pb(Zr) z Ti 1-z O3, Pb(Zr) z Ti 1-z Nd₂O₃ is a solid solution formed by lead titanate (PbTiO₃) and lead zirconate (PbZrO₃), with a molar ratio of lead zirconate (PbZrO₃) to lead titanate (PbTiO₃) of z:(1-z); xmol% represents the proportion of Nd₂O₃ in Pb(ZrO₃). z Ti 1-z The molar percentage of Cr₂O₃, expressed as ymol%, represents the proportion of Cr₂O₃ in Pb(Zr)₂O₃. z Ti1-z The molar percentage of O3.

[0005] Another object of the present invention is to provide a method for preparing the above-mentioned PZT-based piezoelectric ceramic material.

[0006] Application of the above-mentioned PZT-based piezoelectric ceramic materials in high-temperature piezoelectric accelerometers.

[0007] The objective of this invention is achieved through the following technical solution.

[0008] A PZT-based piezoelectric ceramic material comprises: lead zirconate titanate (PZT) and doping elements, wherein the doping elements are neodymium (Nd) and chromium (Cr), the doping amount of neodymium (Nd) is 2x mol% of lead zirconate titanate (PZT), the doping amount of chromium (Cr) is 2y mol% of lead zirconate titanate (PZT), 0.4 ≤ x ≤ 0.8, 0.15 ≤ y ≤ 0.25, and the structural formula of lead zirconate titanate (PZT) is Pb(Zr) z Ti 1-z Lead zirconate titanate (PZT) is a solid solution formed by lead titanate (PbTiO3) and lead zirconate (PbZrO3), with the molar ratio of lead zirconate (PbZrO3) to lead titanate (PbTiO3) being z:(1-z), where 0.53≤z≤0.55.

[0009] A method for preparing a PZT-based piezoelectric ceramic material includes the following steps:

[0010] Step 1: Prepare lead source, zirconium source, titanium source, neodymium source and chromium source as raw materials, mix the raw materials until uniform, ball mill for the first time to obtain a mixture, pre-calcine at 850~950℃ for 2~4 hours, ball mill for the second time to obtain a secondary ball-milled powder. The ratio of lead in lead source, zirconium in zirconium source, titanium in titanium source, neodymium in neodymium source and chromium in chromium source by molar amount is 1:z:(1-z):0.02x:0.02y, 0.4≤x≤0.8, 0.15≤y≤0.25, 0.53≤z≤0.55;

[0011] In step 1, the lead source is lead tetroxide (Pb3O4), the zirconium source is zirconium dioxide (ZrO2), the titanium source is titanium dioxide (TiO2), the neodymium source is neodymium trioxide (Nd2O3), and the chromium source is chromium trioxide (Cr2O3).

[0012] In step 1, both the first and second ball milling are wet ball milling processes. The medium used in the wet ball milling is anhydrous ethanol, the wet ball milling time is 20-30 hours, and the wet ball milling speed is 350-450 r / min.

[0013] In the above technical solution, after wet ball milling, drying is carried out at a temperature of 60~80℃ for 4~6 hours.

[0014] Step 2: Granulate the secondary ball-milled powder, sieve it, and press it into shape to obtain a green sheet;

[0015] In step 2, the pressing pressure is 6~8 MPa.

[0016] In step 2, the granulation uses a binder, the mass of which is 1-5 wt% of the secondary ball-milled powder.

[0017] In the above technical solution, the adhesive is a polyvinyl alcohol aqueous solution, and the content of polyvinyl alcohol in the polyvinyl alcohol aqueous solution is 5~8wt%.

[0018] Step 3: Remove the binder from the green sheet and sinter it for the first time at 1150~1250℃ to obtain ceramic material;

[0019] In step 3, the temperature for degumming is 800~850℃, and the degumming time is 2~4h.

[0020] In step 3, the first sintering time is 1 to 3 hours.

[0021] Step 4: The ceramic material is sequentially coated with high-temperature silver paste, sintered a second time, and polarized under high pressure to obtain PZT-based piezoelectric ceramic material.

[0022] In step 4, the temperature of the second sintering is 600~650℃, and the time of the second sintering is 30~60min.

[0023] In step 4, the high-voltage polarization includes polarizing in silicone oil at 120~160℃ with a polarization field strength of 3~5kV / mm for 15~30min.

[0024] Application of the above-mentioned PZT-based piezoelectric ceramic materials in high-temperature piezoelectric accelerometers.

[0025] In the above technical solution, the sensitivity deviation of the high-temperature piezoelectric accelerometer at 300 ℃ is 11%~13%.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. This invention, by introducing Nd and Cr ions with different modification effects, obtains PZT-based piezoelectric ceramic materials with high piezoelectric properties and temperature stability. These materials have a room temperature dielectric constant of 16.14–18.15, a room temperature dielectric loss of 2.23%–2.36%, and a maximum polarization of 42.0–44.5 μC / cm. 2The coercive field strength is 1.15~1.20kV / mm, the room temperature piezoelectric constant is 400~413pC / N, and the planar electromechanical coupling coefficient is 0.540~0.569.

[0028] 2. The PZT-based piezoelectric ceramic material of the present invention exhibits excellent high-temperature stability, with a depolarization temperature T0. d After annealing at 300℃ multiple times or aging at room temperature for 120 days at 400℃, the room temperature piezoelectric constant only decreases by about 5%.

[0029] 3. The preparation method of this invention adopts the traditional solid-state reaction method, which is simple to operate and has low cost. Nd₂O₃ and Cr₂O₃, as dopants, respectively act as soft and hard dopants, which is beneficial to the combined improvement of piezoelectric properties and temperature stability. This allows for the maintenance of overall performance without degradation at high temperatures. Therefore, PZT-based piezoelectric ceramic materials can be considered excellent candidate materials for piezoelectric elements in high-temperature piezoelectric accelerometers. This invention effectively solves the technical problem that existing lead-based piezoelectric ceramic materials are difficult to simultaneously possess piezoelectric properties and temperature stability at 300℃. Attached Figure Description

[0030] Figure 1 The images show the XRD patterns of the PZT-based piezoelectric ceramic materials prepared in Examples 1-2 and Comparative Examples 1-5, where (a) is the XRD pattern of the PZT-based piezoelectric ceramic materials prepared in Examples 1-2 and Comparative Examples 1-5. XRD within the range of 20~60°, (b) is a magnified view of (a);

[0031] Figure 2 The images show cross-sectional SEM images of PZT-based piezoelectric ceramic materials and curves showing the variation of average grain size and density. (a) to (g) are cross-sectional SEM images of PZT-based piezoelectric ceramic materials prepared according to Comparative Example 1, Example 1, Example 2, Comparative Example 2, Comparative Example 3, Comparative Example 4 and Comparative Example 5, respectively. (h) shows curves showing the variation of average grain size and density of PZT-based piezoelectric ceramic materials prepared according to Comparative Examples 1 to 5 and Examples 1 to 2.

[0032] Figure 3 The dielectric temperature spectra of the PZT-based piezoelectric ceramic materials prepared in Examples 1-2 and Comparative Examples 1-5 are shown.

[0033] Figure 4 The hysteresis loops are shown in (a) and (b), which are the hysteresis loops of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2, respectively.

[0034] Figure 5 The hysteresis loops are the hysteresis loops of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1 to 5, respectively.

[0035] Figure 6 The curves showing the variation of polarization intensity and coercive field strength of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 and Examples 1-2 are shown.

[0036] Figure 7 The XRD patterns of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 are shown below. (a) shows the XRD patterns of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and 8-11. XRD within the range of 20~60°, (b) is a magnified view of (a);

[0037] Figure 8 The images show cross-sectional SEM images of PZT-based piezoelectric ceramic materials and curves showing the variation of average grain size and density. (a) to (e) are cross-sectional SEM images of PZT-based piezoelectric ceramic materials prepared in Comparative Examples 8, 9, 2, 10, and 11, respectively. (f) shows curves showing the variation of average grain size and density of PZT-based piezoelectric ceramic materials prepared in Examples 2 and 8 to 11.

[0038] Figure 9 The figures show the hysteresis loop and the curves showing the changes in polarization intensity and coercive field strength. Among them, (a) to (e) are the hysteresis loops of the PZT-based piezoelectric ceramic materials prepared by Comparative Examples 8, 9, 2, 10 and 11, respectively, and (f) is the curve showing the changes in polarization intensity and coercive field strength of the PZT-based piezoelectric ceramic materials prepared by Examples 2 and 8 to 11.

[0039] Figure 10 The piezoelectric property variation curves of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 are shown.

[0040] Figure 11 The unipolar strain curves of the PZT-based piezoelectric ceramic material prepared in Example 1 at different temperatures are shown.

[0041] Figure 12 The unipolar strain curves of the PZT-based piezoelectric ceramic material prepared in Example 2 at different temperatures are shown.

[0042] Figure 13 The curves showing the piezoelectric constant of the PZT-based piezoelectric ceramic material prepared in Example 1 as a function of aging days and the piezoelectric constant as a function of annealing times are shown. (a) is the curve showing the piezoelectric constant as a function of aging days, and (b) is the curve showing the piezoelectric constant as a function of annealing times.

[0043] Figure 14 The curves showing the piezoelectric constant of the PZT-based piezoelectric ceramic material prepared in Example 2 as a function of aging days and the piezoelectric constant as a function of annealing times are shown. (a) is the curve showing the piezoelectric constant as a function of aging days, and (b) is the curve showing the piezoelectric constant as a function of annealing times.

[0044] Figure 15 This is a schematic diagram of the structure of a high-temperature piezoelectric accelerometer.

[0045] Figure 16 This is the sensitivity deviation curve of a high-temperature piezoelectric accelerometer.

[0046] Among them, 1: base, 1-1: center column, 2: core mounting bolt, 3: mass block, 4: shell cover, 5-1: connector shell, 5-2: connector pin, 6: ceramic plate, 7: electrode plate. Detailed Implementation

[0047] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0048] In the following examples and comparative examples, the lead source is lead tetroxide (Pb3O4), the zirconium source is zirconium dioxide (ZrO2), the titanium source is titanium dioxide (TiO2), the neodymium source is neodymium trioxide (Nd2O3), the chromium source is chromium trioxide (Cr2O3), the lanthanum source is La2O3, and the cerium source is CeO2.

[0049] In the following examples and comparative examples, both the first and second ball milling were wet ball milling, the first and second ball milling times were both 20 hours, and the first and second ball milling speeds were both 350 r / min.

[0050] High-temperature silver paste: purchased from Shanghai Julong Electronic Technology Co., Ltd.

[0051] Examples 1-2 and Comparative Examples 1-11

[0052] A method for preparing a PZT-based piezoelectric ceramic material includes the following steps:

[0053] Step 1: Prepare lead, zirconium, titanium, neodymium, and chromium sources as raw materials. Mix the raw materials until uniform, perform a first ball milling (wet ball milling), dry at 70℃ for 5 hours, pass through a 70-mesh sieve to obtain a mixture, pre-calcine at 850℃ for 3 hours (heating rate from room temperature to 850℃ is 2℃ / min), perform a second ball milling (wet ball milling), dry at 80℃ for 4 hours, pass through a 70-mesh sieve to obtain a second-milled powder. The ratio of lead in the lead source, zirconium in the zirconium source, titanium in the titanium source, neodymium in the neodymium source, and chromium in the chromium source, by molar amount, is 1:z:(1-z):0.02x:0.02y. The values ​​of x, y, and z are shown in Table 1. The medium used for wet ball milling is anhydrous ethanol, and the grinding balls used in wet ball milling are zirconium oxide balls. During the first ball milling, the ratio of grinding balls, raw materials, and anhydrous ethanol by mass parts was 2:1:1; during the second ball milling, the ratio of grinding balls, mixed materials, and anhydrous ethanol by mass parts was 2:1:1.

[0054] Step 2: Granulate the secondary ball-milled powder, pass it through a 70-mesh sieve, and press it into shape under a pressure of 6 MPa to obtain a green sheet with a diameter of 10 mm and a thickness of 1 mm. A binder is used in the granulation process, with the binder's mass being 3 wt% of the secondary ball-milled powder. The binder is a polyvinyl alcohol aqueous solution with a polyvinyl alcohol content of 8 wt%.

[0055] Step 3: The green sheet is subjected to debinding treatment at 800℃ for 4 hours (heating rate to 800℃ is 5℃ / min), and then sintered for the first time at 1200℃ (heating rate to 1200℃ is 2℃ / min). It is then cooled to room temperature in the furnace to obtain ceramic material. The first sintering time is 2 hours.

[0056] Step 4: The ceramic material is sequentially coated with high-temperature silver paste (by screen printing, high-temperature silver paste is coated on both sides of the ceramic material to form a conductive silver layer), sintered a second time, and polarized under high pressure to obtain PZT-based piezoelectric ceramic material. The temperature of the second sintering is 600℃ (the rate of heating to 600℃ is 5℃ / min), and the time of the second sintering is 30min. The high-pressure polarization includes polarizing in silicone oil at 120℃ with a polarization field strength of 3kV / mm for 30min.

[0057] Table 1

[0058]

[0059] Comparative Example 12

[0060] A method for preparing a PZT-based piezoelectric ceramic material includes the following steps:

[0061] Step 1: Prepare lead, zirconium, titanium, lanthanum, and chromium sources as raw materials. Mix the raw materials until homogeneous, perform a first ball milling (wet ball milling), dry at 70℃ for 5 hours, and pass through a 70-mesh sieve to obtain a mixture. Pre-calcine at 850℃ for 3 hours (heating rate from room temperature to 850℃ is 2℃ / min), perform a second ball milling (wet ball milling), dry at 80℃ for 4 hours, and pass through a 70-mesh sieve to obtain a second-milled powder. The ratio of lead in the lead source, zirconium in the zirconium source, titanium in the titanium source, lanthanum in the lanthanum source, and chromium in the chromium source, by molar amount, is 1:0.54:0.46:0.016:0.004. The medium used in the wet ball milling is anhydrous ethanol, and the grinding balls used in the wet ball milling are zirconium oxide balls. During the first ball milling, the ratio of grinding balls, raw materials, and anhydrous ethanol by mass parts was 2:1:1; during the second ball milling, the ratio of grinding balls, mixed materials, and anhydrous ethanol by mass parts was 2:1:1.

[0062] Step 2: Granulate the secondary ball-milled powder, pass it through a 70-mesh sieve, and press it into shape under a pressure of 6 MPa to obtain a green sheet with a diameter of 10 mm and a thickness of 1 mm. A binder is used in the granulation process, with the binder's mass being 3 wt% of the secondary ball-milled powder. The binder is a polyvinyl alcohol aqueous solution with a polyvinyl alcohol content of 8 wt%.

[0063] Step 3: The green sheet is subjected to debinding treatment at 800℃ for 4 hours (heating rate to 800℃ is 5℃ / min), and then sintered for the first time at 1150℃ (heating rate to 1150℃ is 2℃ / min). It is then cooled to room temperature in the furnace to obtain ceramic material. The first sintering time is 2 hours.

[0064] Step 4: The ceramic material is sequentially coated with high-temperature silver paste (high-temperature silver paste is coated on both sides of the ceramic material by screen printing), sintered a second time, and polarized under high pressure to obtain PZT-based piezoelectric ceramic material. The temperature of the second sintering is 600℃ (the rate of heating to 600℃ is 5℃ / min), and the time of the second sintering is 30min. The high-pressure polarization includes polarization in silicone oil at 120℃ with a polarization field strength of 3kV / mm for 30min.

[0065] Comparative Example 13

[0066] A method for preparing a PZT-based piezoelectric ceramic material includes the following steps:

[0067] Step 1: Prepare lead, zirconium, titanium, cerium, and chromium sources as raw materials. Mix the raw materials until homogeneous, perform a first ball milling (wet ball milling), dry at 70℃ for 5 hours, pass through a 70-mesh sieve to obtain a mixture, pre-calcine at 850℃ for 3 hours (heating rate from room temperature to 850℃ is 2℃ / min), perform a second ball milling (wet ball milling), dry at 80℃ for 4 hours, pass through a 70-mesh sieve to obtain a second-milled powder. The ratio of lead in the lead source, zirconium in the zirconium source, titanium in the titanium source, cerium in the cerium source, and chromium in the chromium source, by molar amount, is 1:0.54:0.46:0.016:0.004. The medium used in the wet ball milling is anhydrous ethanol, and the grinding balls used in the wet ball milling are zirconium oxide balls. During the first ball milling, the ratio of grinding balls, raw materials, and anhydrous ethanol by mass parts was 2:1:1; during the second ball milling, the ratio of grinding balls, mixed materials, and anhydrous ethanol by mass parts was 2:1:1.

[0068] Step 2: Granulate the secondary ball-milled powder, pass it through a 70-mesh sieve, and press it into shape under a pressure of 6 MPa to obtain a green sheet with a diameter of 10 mm and a thickness of 1 mm. A binder is used in the granulation process, with the binder's mass being 3 wt% of the secondary ball-milled powder. The binder is a polyvinyl alcohol aqueous solution with a polyvinyl alcohol content of 8 wt%.

[0069] Step 3: The green sheet is subjected to debinding treatment at 800℃ for 4 hours (heating rate to 800℃ is 5℃ / min), and then sintered for the first time at 1180℃ (heating rate to 1180℃ is 2℃ / min). It is then cooled to room temperature in the furnace to obtain ceramic material. The first sintering time is 2 hours.

[0070] Step 4: The ceramic material is sequentially coated with high-temperature silver paste (high-temperature silver paste is coated on both sides of the ceramic material by screen printing), sintered a second time, and polarized under high pressure to obtain PZT-based piezoelectric ceramic material. The temperature of the second sintering is 600℃ (the rate of heating to 600℃ is 5℃ / min), and the time of the second sintering is 30min. The high-pressure polarization includes polarization in silicone oil at 120℃ with a polarization field strength of 3kV / mm for 30min.

[0071] The XRD patterns of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1, 2, 3, 4, and 5 are shown below. Figure 1 (a) and Figure 1 As shown in (b), Figure 1 (b) is Figure 1 A magnified view of (a). From Figure 1 As shown in (a), the PZT-based piezoelectric ceramic materials prepared in Examples 1-2 and Comparative Examples 1-5 all exhibit a single perovskite structure. The x values ​​corresponding to Comparative Examples 1, 1, 2, 3, 4, and 5 are 0, 0.4, 0.8, 1.2, 1.6, 2.0, and 2.4, respectively. With the increase of the x value (i.e., the increase of Nd₂O₃ doping), all diffraction peaks shift slightly to the left, indicating that Nd₂O₃ doping... 3+ Successfully entered the crystal lattice. Figure 1 As can be seen from (b), the diffraction peak near 45° corresponding to Comparative Example 1 is a single peak (i.e., monoclinic phase). The diffraction peaks near 45° corresponding to Examples 1-2 and Comparative Examples 2-5 split from the single peak into two distinct double peaks (i.e., monoclinic phase and tetragonal phase). The content of monoclinic phase and tetragonal phase was obtained by refining the XRD results, as shown in Table 2 (the weighted residual factor and residual factor in Table 2 are used to characterize the accuracy of the refinement). As can be seen from Table 2, as the x value increases, the content of monoclinic phase gradually decreases and the content of tetragonal phase gradually increases.

[0072] Table 2

[0073]

[0074] Figure 2 (a) ~ Figure 2(g) are, in order, cross-sectional SEM images of the PZT-based piezoelectric ceramic materials prepared according to Comparative Example 1, Example 1, Example 2, Comparative Example 2, Comparative Example 3, Comparative Example 4, and Comparative Example 5. (g) Figure 2 (a) ~ Figure 2 As shown in (g), the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 1 is 5.81 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Example 1 is 4.96 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Example 2 is 1.83 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 2 is 1.12 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 3 is 0.82 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 4 is 0.78 μm, and the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 5 is 0.64 μm. The average grain size is plotted on... Figure 2 In (h), as the x value increases, the average grain size decreases from 5.81 μm to 0.64 μm, indicating that Nd 3+ The introduction of [a specific ingredient] can refine the grain size; the average grain size and density of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 and Examples 1-2 are plotted on [a specific graph]. Figure 2 In (h). By Figure 2 As can be seen from (h), the densities of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 and Examples 1-2 are all around 7.70 g / cm³. 3 The above demonstrates that PZT-based piezoelectric ceramic materials have good density.

[0075] Impedance analyzer was used to test the dielectric properties of the ceramic material, obtaining the room temperature dielectric constant, room temperature dielectric loss, and Curie temperature. Simultaneously, the resonant and anti-resonant frequencies were measured, leading to the planar electromechanical coupling coefficient. Ferroelectric analyzer was used to test the hysteresis loops of the ceramic material under electric field strengths of 0.5 kV / mm, 1.0 kV / mm, 1.5 kV / mm, 2.0 kV / mm, 2.5 kV / mm, and 3 kV / mm, obtaining the maximum polarization, remanent polarization, and coercive field strength. A quasi-static d-axis was used... 33 The room-temperature piezoelectric constant of the ceramic material was measured using a testing instrument. The ceramic material was one of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-7 and Examples 1-2.

[0076] The room temperature dielectric constant (ε) of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-7 and Examples 1-2 r , RT ), room temperature dielectric loss (tanδ), Curie temperature (T) C ), maximum polarization intensity (P) maxCoercive field strength (E) c ), room temperature piezoelectric constant (d 33 ) and planar electromechanical coupling coefficient (k p As shown in Table 3.

[0077] Table 3

[0078]

[0079] As shown in Table 3, in Comparative Examples 1-5 and Examples 1-2, the room temperature dielectric constant of the PZT-based piezoelectric ceramic materials generally increased with the increase of x value (i.e., the increase of Nd₂O₃ doping amount), indicating that Nd₂O₃ plays the role of a soft dopant in the doping substitution process. 3+ Pb occupying the A site in the solid solution 2+ The position of the lead ion creates lead ion vacancies to maintain the electrical neutrality of the crystal, and the lattice is distorted, so that the electric domains can move under a small electric field and stress, thereby increasing the room temperature dielectric constant.

[0080] The dielectric temperature spectra of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 and Examples 1-2 are as follows: Figure 3 As shown. From Figure 3 The dielectric temperature spectrum shows that the Curie temperature of the PZT-based piezoelectric ceramic material (without Nd2O3 doping) prepared in Comparative Example 1 is the highest, at 403℃. As the amount of Nd2O3 doping increases, the Curie temperature of the PZT-based piezoelectric ceramic material gradually decreases. The Curie temperature of the PZT-based piezoelectric ceramic material prepared in Example 1 is as high as 397.3℃, which is closest to that of Comparative Example 1.

[0081] The hysteresis loops of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 are respectively as follows: Figure 4 (a) ~ Figure 4 As shown in (b), the hysteresis loops of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 are respectively as follows: Figure 5 (a) ~ Figure 5 As shown in (e), the maximum polarization intensity (P) corresponding to Examples 1-2 and Comparative Examples 1-5 was obtained based on the corresponding hysteresis loops. max ), remanent polarization intensity (P) r ) and coercive field strength (E c The polarization intensity (maximum polarization intensity (P)) of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 1-5 and Examples 1-2 max ), remanent polarization intensity (P) r and coercive field strength (E) c )like Figure 6 As shown in Table 3 and Figure 6It can be seen that in Comparative Examples 1-5 and Examples 1-2, as the value of x increases (i.e., the amount of Nd2O3 doping increases), the maximum polarization intensity (P) increases. max ) and remanent polarization intensity (P r The coercive field strength first increases and then decreases, gradually increasing, and Examples 1 and 2 reach the optimal equilibrium. The spontaneous polarization degree of the PZT-based piezoelectric ceramic material prepared in Comparative Example 1 is significantly lower than that in Examples 1 and 2, proving that Examples 1 and 2 have higher piezoelectric properties. This is due to the fact that Examples 1 and 2 have a two-phase coexisting phase structure.

[0082] As shown in Table 3, in Comparative Examples 1-5 and Examples 1-2, as the value of x increases, the room temperature piezoelectric constant (d) decreases. 33 The value first increases and then decreases; the values ​​of d in Examples 1 and 2 are as follows: 33 Relatively large, d in Examples 1 and 2 33 They are 400 pC / N and 413 pC / N, respectively. p The variation of x with d shows a similarity. 33 The trend of change is basically the same in Examples 1 and 2. p The values ​​are 0.540 and 0.569, respectively. In summary, Examples 1 and 2 exhibit better overall performance.

[0083] As shown in Table 3, comparing Example 1, Comparative Example 6, and Comparative Example 7, the Curie temperature of the PZT-based piezoelectric ceramic material increases significantly with the increase of the y value (i.e., the increase of Cr2O3 doping amount). This indicates that the addition of Cr2O3 helps to improve the temperature stability of the PZT-based piezoelectric ceramic material. However, when the Cr2O3 doping amount is too high (Comparative Example 7), the ε of the PZT-based piezoelectric ceramic material decreases. r , RT P max d 33 and k p The dielectric loss decreases sharply because of its low solid solution limit in the crystal lattice. Therefore, when the Cr2O3 doping amount is too high, it will accumulate at the grain boundaries, thus greatly affecting the electrical properties of PZT-based piezoelectric ceramic materials. This indicates that Cr2O3 mainly plays the role of hard doping in PZT-based piezoelectric ceramic materials, and appropriate doping can effectively improve the dielectric loss, high-temperature stability, and durability of piezoelectric ceramics. In Examples 1, 6, and 7, the PZT-based piezoelectric ceramic material in Example 1 (y=0.2) has the lowest coercive field strength (1.15 kV / mm), indicating that it has a strong domain flipping ability under an applied electric field and possesses relatively high electrical performance.

[0084] The XRD patterns of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 are shown below. Figure 7 (a) and Figure 7As shown in (b), Figure 7 (b) is Figure 7 A magnified view of (a), (002) T and (200) T The characteristic peak of the tetragonal phase is (200). R The characteristic peaks are for the trigonal phase. The crystal structures of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 8 and 9 exhibit a tetragonal phase; the crystal structure of the PZT-based piezoelectric ceramic material prepared in Example 2 shows a coexistence of trigonal and tetragonal phases; the crystal structure of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 10 and 11 is trigonal. The phase structure with coexistence of trigonal and tetragonal phases has a relatively flat Gibbs free energy curve, which is conducive to domain motion and thus helps to improve the piezoelectric properties of the system.

[0085] Figure 8 (a) ~ Figure 8 (e) shows cross-sectional SEM images of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 8, 9, 2, 10, and 11, respectively. Figure 8 (a) ~ Figure 8 As shown in (e), the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 8 is 1.61 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 9 is 1.76 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Example 2 is 1.83 μm, the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 10 is 2.12 μm, and the average grain size of the PZT-based piezoelectric ceramic material prepared in Comparative Example 11 is 2.08 μm. The PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 all exhibit a dense and well-grown microstructure with no obvious pores or defects. The average grain size and density of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 are plotted on [the graph]. Figure 8 In (f), by Figure 8 As shown in (f), the density of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 is maintained at 7.75 g / cm³. 3 above.

[0086] Impedance analyzer was used to test the dielectric properties of the ceramic material, obtaining the room temperature dielectric constant, room temperature dielectric loss, and Curie temperature. Simultaneously, the resonant and anti-resonant frequencies were measured, leading to the planar electromechanical coupling coefficient. Ferroelectric analyzer was used to test the hysteresis loops of the ceramic material under electric field strengths of 0.5 kV / mm, 1.0 kV / mm, 1.5 kV / mm, 2.0 kV / mm, 2.5 kV / mm, and 3 kV / mm, obtaining the maximum polarization, remanent polarization, and coercive field strength. A quasi-static d-axis was used...33 The room-temperature piezoelectric constant of the ceramic material was measured using a testing instrument. The ceramic material was one of Examples 2 and Comparative Examples 8-11. The room-temperature dielectric constant (ε) of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 is shown below. r , RT ), room temperature dielectric loss (tanδ), Curie temperature (T) C ), maximum polarization intensity (P) max Coercive field strength (E) c ), room temperature piezoelectric constant (d 33 ) and planar electromechanical coupling coefficient (k p As shown in Table 4.

[0087] Table 4

[0088]

[0089] As can be seen from Table 4, with the increase of z value, ε r , RT The ε first increases and then decreases; at z=0.54, ε r , RT The highest value is 1815, which is due to the phase structure of the PZT-based piezoelectric ceramic material prepared in Example 2, which has a coexistence of trigonal and tetragonal phases and a high degree of spontaneous polarization. The dielectric loss increases with increasing z-value, mainly due to the increased heat generated by enhanced domain wall motion. The room temperature piezoelectric constant d... 33 And planar electromechanical coupling coefficient k p The value of d first increases and then decreases with increasing z value. When z = 0.54, d 33 Up to 413 pC / N, k p The value reached 0.569. Overall, among Examples 2 and Comparative Examples 8-11, the PZT-based piezoelectric ceramic material prepared in Example 2 (z = 0.54) exhibited better performance.

[0090] The hysteresis loops of the PZT-based piezoelectric ceramic materials prepared in Comparative Examples 8, 9, 2, 10, and 11 are as follows: Figure 9 (a) ~ Figure 9 As shown in (e), the maximum polarization intensity (P) corresponding to Example 2 and Comparative Examples 8-11 was obtained based on the corresponding hysteresis loops. max ), remanent polarization intensity (P) r ) and coercive field strength (E c The polarization intensity (maximum polarization intensity (P)) of the PZT-based piezoelectric ceramic materials prepared in Examples 2 and Comparative Examples 8-11 max ), remanent polarization intensity (P) r and coercive field strength (E) c)like Figure 9 As shown in (f), as the z value increases, P max and P r The coercive field strength initially increases and then decreases, gradually decreasing with increasing z value. When z = 0.54, P... max and P r The maximum coercive field strength is achieved, while the minimum coercive field strength is relatively low, thus reaching an optimal balance.

[0091] The room temperature dielectric constant, room temperature dielectric loss, Curie temperature, and planar electromechanical coupling coefficient of the ceramic material were determined using an impedance analyzer. The maximum polarization intensity of the ceramic material was determined using a ferroelectric analyzer. A quasi-static d-axis was used. 33 The room-temperature piezoelectric constant of the ceramic material was determined using a testing instrument. The ceramic material was one of the PZT-based piezoelectric ceramic materials prepared in Example 2, Comparative Example 12, and Comparative Example 13. The room-temperature dielectric constant (ε0) of the PZT-based piezoelectric ceramic materials prepared in Example 2, Comparative Example 12, and Comparative Example 13 is also described. r , RT ), room temperature dielectric loss (tanδ), Curie temperature (T) C ), maximum polarization intensity (P) max ), room temperature piezoelectric constant (d 33 ) and planar electromechanical coupling coefficient (k p As shown in Table 5.

[0092] Table 5

[0093]

[0094] Room temperature dielectric constant (ε) of Comparative Examples 12 and 13 r , RT ), maximum polarization intensity (P) max ), room temperature piezoelectric constant (d 33 ) and planar electromechanical coupling coefficient (k p The Nd₂O₃ doping coefficients of Comparative Example 1 (without Nd doping) are higher than those of Comparative Example 1. Nd, La, and Ce are all lanthanides with similar chemical properties, indicating that doping with Nd homologues can improve the electrical properties of piezoelectric ceramics to some extent. However, the room temperature dielectric constant, Curie temperature, maximum polarization intensity, room temperature piezoelectric constant, and planar electromechanical coupling coefficient of Comparative Examples 12 and 13 are all lower than those of Example 2. This is because La and Ce have high tolerance factors with the PZT perovskite structure, and doping with La or Ce would disrupt the stability of the perovskite structure. This demonstrates the irreplaceable nature of Nd₂O₃ doping.

[0095] To further test the performance of PZT-based piezoelectric ceramic materials under high-temperature conditions, high-temperature annealing electrical tests were conducted on the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2. The conditions for the high-temperature annealing electrical tests included holding at T1℃ for 30 min, with T1℃ being one of the following values: 25℃, 50℃, 75℃, 100℃, 125℃, 150℃, 175℃, 200℃, 225℃, 250℃, 275℃, 300℃, 325℃, 350℃, 375℃, 400℃, 425℃, and 450℃. The test results are as follows: Figure 10 As shown. By Figure 10 It can be seen that, Example 1 ( Figure 10 In the example "x=0.4") and Example 2 ( Figure 10 The PZT-based piezoelectric ceramic materials prepared with "x=0.8" showed a relatively stable temperature variation trend in the range of 25℃ (room temperature) to 300℃. The depolarization temperature T of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 was also relatively stable. d Both were prepared at 400 °C, and the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 exhibited excellent thermal stability. Furthermore, the room-temperature piezoelectric constant d of Example 1 was [not specified]. 33 The room temperature piezoelectric constant d of Example 2 is 400 pC / N. 33 With a pC / N ratio of 413, it exhibits excellent piezoelectric properties. The excellent piezoelectric properties and the relatively stable variation trend in the range of room temperature to 300 °C demonstrate that the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 have great potential for application in high-temperature piezoelectric accelerometers.

[0096] At T2℃, an electric field of 2 kV / mm was applied to the PZT-based piezoelectric ceramic material prepared in Example 1 (without high-temperature annealing electrical testing) to conduct unipolar strain tests, yielding... Figure 11 The unipolar strain curves are shown. A 2 kV / mm electric field was applied to the PZT-based piezoelectric ceramic material (without high-temperature annealing electrical testing) prepared in Example 2 at 20–300 °C to perform unipolar strain testing, yielding the results. Figure 12 The unipolar strain curves are shown. T2℃ = 20℃, 60℃, 100℃, 140℃, 180℃, 220℃, 260℃, and 300℃. In the unipolar strain curves, the horizontal axis represents the temperature of the unipolar strain test, and the vertical axis represents the strain value. The strain value can be expressed as a percentage (%) or picometers per millimeter (pm / mm). In this invention, it is expressed as a percentage (%). The conversion relationship between percentage (%) and picometers per millimeter (pm / mm) is: 1% = 10. 7 pm / mm. By Figure 11 and Figure 12It can be seen that the strain values ​​of the PZT-based piezoelectric ceramic material prepared in Example 1 at 20℃, 60℃, 100℃, 140℃, 180℃, 220℃, 260℃, and 300℃ are 0.220%, 0.225%, 0.233%, 0.239%, 0.244%, 0.246%, and 0.248%, respectively. The strain values ​​of the PZT-based piezoelectric ceramic material prepared in Example 2 at 20℃, 60℃, 100℃, 140℃, 180℃, 220℃, 260℃, and 300℃ are 0.233%, 0.239%, 0.243%, 0.247%, 0.249%, 0.250%, 0.252%, and 0.255%, respectively. This indicates that the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 have good temperature stability. According to d... 33 * =S max / E Calculate the inverse piezoelectric coefficient d at 20℃ 33 * , among which, S max S represents the maximum strain value measured by the unipolar strain curve, and E represents the electric field strength applied during the unipolar strain test, i.e., 2 kV / mm. In Example 1, S max =0.220% (i.e., 2.20 × 10) 6 (pm / mm), the d of the PZT-based piezoelectric ceramic material prepared in Example 1 was calculated. 33 * The value is 1100 pm / V, and in Example 2, S max =0.233% (i.e., 2.33 × 10) 6 (pm / mm), the d of the PZT-based piezoelectric ceramic material prepared in Example 2 was calculated. 33 * The value is 1165 pm / V, indicating a high contribution from reversible domain walls.

[0097] The PZT-based piezoelectric ceramic material prepared in Example 1 was aged at room temperature for D days, and the resulting piezoelectric constant variation graph is shown below. Figure 13 As shown in (a), D = 0, 5, 10, 15, 20, 30, 40, 60, 80, 100, or 120. The PZT-based piezoelectric ceramic material prepared in Example 1 was annealed four times at 300°C, with each annealing time being 12 hours. The corresponding d for each annealing... 33 like Figure 13 As shown in (b).

[0098] The PZT-based piezoelectric ceramic material prepared in Example 2 was aged at room temperature for D days, and the resulting piezoelectric constant variation graph is shown below. Figure 14As shown in (a), D = 0, 5, 10, 15, 20, 30, 40, 60, 80, 100, or 120. The PZT-based piezoelectric ceramic material prepared in Example 2 was annealed four times at 300°C, with each annealing time being 12 hours. The corresponding d for each annealing... 33 like Figure 14 As shown in (b).

[0099] Depend on Figure 13 (a) and Figure 14 As shown in (a), with the increase of aging days, the d of PZT-based piezoelectric ceramic materials... 33 The piezoelectric constants of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 at room temperature after 60 days of aging were 380 pC / N and 395 pC / N, respectively. Compared with the room temperature piezoelectric constants of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 at day 0 of aging (400 pC / N and 413 pC / N, respectively), the room temperature piezoelectric constants decreased by 5% and 4.36%, respectively, demonstrating excellent durability.

[0100] Depend on Figure 13 (b) and Figure 14 As can be seen from (b), after the first annealing, the d of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2... 33 Both decreased by approximately 15 pC / N during the second annealing. 33 The piezoelectric constants of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 after the fourth annealing were 381 pC / N and 395 pC / N, respectively. Compared with the piezoelectric constants of the PZT-based piezoelectric ceramic materials prepared in Examples 1 and 2 after the fourth annealing, the piezoelectric constants decreased by 4.75% and 4.36%, respectively. This demonstrates their reliability in repeated use under harsh high-temperature environments and lays a good foundation for the application of PZT-based piezoelectric ceramic materials in high-temperature sensors.

[0101] Test Example 1

[0102] To better evaluate the performance of PZT-based piezoelectric ceramic materials in high-temperature piezoelectric accelerometers, a high-temperature piezoelectric accelerometer was designed. For example... Figure 15As shown, the high-temperature piezoelectric accelerometer sensor includes: a core, a cover 4, and a connector. The core includes: a base 1, two mass blocks 3, and two sets of piezoelectric elements. Each set of piezoelectric elements includes: one electrode plate 7 and one ceramic plate 6. The cover 4 is fitted onto the base 1 and together they form a cavity. A vertically arranged central column 1-1 is integrally formed on the upper part of the base 1. A horizontally arranged through hole is formed on the central column 1-1. Core mounting bolts 2 are used. Through the through hole, both the ceramic plate 6 and the electrode plate 7 are annular. Two sets of piezoelectric elements are fitted onto the core mounting bolts 2, with one set of piezoelectric elements on each side of the central column 1-1 (in each set, the ceramic plate 6 is closer to the central column 1-1, and the electrode plate 7 is farther away). Each set of piezoelectric elements is pressed against the side of the central column 1-1 by a mass block 3 (also annular). The positive electrode of each ceramic plate 6 is in contact with the electrode plate 7, and the negative electrode of each ceramic plate 6 is in contact with the central column 1-1 (the positive and negative electrodes of the ceramic plate 6 are connected by a quasi-static d...). 33 (Tester determined);

[0103] The connector is fixedly mounted on the top of the housing 4. The connector includes: a connector housing 5-1 and a connector pin 5-2 fixedly mounted inside the connector housing 5-1. Electrode leads are led out from the electrode plate 7 and electrically connected to the connector pin 5-2. The connector pin 5-2 is connected to the positive terminal of the external connector. The housing 4 and the base 1 are both made of conductive materials. The housing 4 is connected to the negative terminal of the external connector.

[0104] The thickness of ceramic sheet 6 is 0.8 mm. Ceramic sheet 6 is one of the PZT-based piezoelectric ceramic materials prepared in Examples 1-2, Comparative Examples 2-3, and Comparative Example 9.

[0105] The external connector is an Agilent 4294A tester, which is used to test the sensitivity of the high-temperature piezoelectric accelerometer. The high-temperature piezoelectric accelerometer is heated from 25℃ to 300℃ (heating rate 5℃ / min), and the sensitivity is tested at 25℃, 50℃, 100℃, 150℃, 200℃, 250℃, and 300℃ during the heating process. When the temperature reaches 300℃, it is held for 2 hours. The sensitivity is then tested again at the first and second hours of the holding period. The sensitivity deviation is calculated based on the sensitivity results. Figure 16 As shown. The high-temperature piezoelectric accelerometer is one of the high-temperature piezoelectric accelerometers prepared from the PZT-based piezoelectric ceramic materials of Examples 1-2, Comparative Examples 2-3, and Comparative Example 9. The formula for calculating the sensitivity deviation is: ΔS(%) = ,in, S(T) represents the sensitivity at the reference temperature (25℃); S(T) represents the sensitivity at the test temperature (test temperature is 25℃, 50℃, 100℃, 150℃, 200℃, 250℃ or 300℃); ΔS(%) represents the percentage change in sensitivity with temperature, i.e., the sensitivity deviation.

[0106] Depend on Figure 16 It can be seen that the sensitivity deviation of the high-temperature piezoelectric accelerometers prepared from the PZT-based piezoelectric ceramic materials of Examples 1-2, Comparative Examples 2-3, and Comparative Example 9 all increased with increasing temperature, and the rate of increase tended to level off at 250℃. The sensitivity deviation of the high-temperature piezoelectric accelerometers prepared from the PZT-based piezoelectric ceramic materials of Examples 1-2 was much lower than that of Comparative Examples 2-3 and Comparative Example 9. The Curie temperature has a significant impact on the sensitivity deviation. The Curie temperature (T0) of the PZT-based piezoelectric ceramic material prepared in Comparative Example 9 is significantly lower. C The PZT-based piezoelectric ceramic materials prepared in Comparative Example 9 are not significantly different from those prepared in Examples 1 and 2. However, the sensitivity deviation of the high-temperature piezoelectric accelerometer prepared from the PZT-based piezoelectric ceramic material in Comparative Example 9 is higher than that in Examples 1 and 2. This indicates that the technical solution of the present invention achieves simultaneous improvement in the performance of both the PZT-based piezoelectric ceramic material and the high-temperature piezoelectric accelerometer prepared from the PZT-based piezoelectric ceramic material.

[0107] The present invention has been described above by way of example. It should be noted that any simple modifications, alterations or other equivalent substitutions that can be made by those skilled in the art without creative effort without departing from the core of the present invention fall within the protection scope of the present invention.

Claims

1. A PZT-based piezoelectric ceramic material, characterized in that, include: Lead zirconate titanate and doping elements neodymium and chromium. The neodymium doping amount is 2x mol% of lead zirconate titanate, and the chromium doping amount is 2y mol% of lead zirconate titanate. The doping values ​​are 0.4 ≤ x ≤ 0.8 and 0.15 ≤ y ≤ 0.

25. The structural formula of lead zirconate titanate is Pb(Zr). z Ti 1-z O3, lead zirconate titanate is a solid solution formed by lead titanate and lead zirconate, and the molar ratio of lead zirconate to lead titanate is z:(1-z), 0.53≤z≤0.

55.

2. A method for preparing a PZT-based piezoelectric ceramic material, characterized in that, Includes the following steps: Step 1: Prepare lead source, zirconium source, titanium source, neodymium source and chromium source as raw materials, mix the raw materials until uniform, ball mill for the first time to obtain a mixture, pre-calcine at 850~950℃ for 2~4 hours, ball mill for the second time to obtain a secondary ball-milled powder. The ratio of lead in lead source, zirconium in zirconium source, titanium in titanium source, neodymium in neodymium source and chromium in chromium source by molar amount is 1:z:(1-z):0.02x:0.02y, 0.4≤x≤0.8, 0.15≤y≤0.25, 0.53≤z≤0.55; Step 2: Granulate the secondary ball-milled powder, sieve it, and press it into shape to obtain a green sheet; Step 3: Remove the binder from the green sheet and sinter it for the first time at 1150~1250℃ to obtain ceramic material; Step 4: The ceramic material is sequentially coated with high-temperature silver paste, sintered a second time, and polarized under high pressure to obtain PZT-based piezoelectric ceramic material.

3. The preparation method according to claim 2, characterized in that, In step 1, the lead source is lead tetroxide, the zirconium source is zirconium dioxide, the titanium source is titanium dioxide, the neodymium source is neodymium trioxide, and the chromium source is chromium trioxide.

4. The preparation method according to claim 2, characterized in that, In step 1, both the first and second ball milling processes are wet ball milling processes, and the medium used in wet ball milling is anhydrous ethanol.

5. The preparation method according to claim 2, characterized in that, In step 2, the granulation uses a binder, the mass of which is 1-5 wt% of the secondary ball-milled powder.

6. The preparation method according to claim 5, characterized in that, The adhesive is an aqueous solution of polyvinyl alcohol, and the content of polyvinyl alcohol in the aqueous solution is 5~8 wt%.

7. The preparation method according to claim 2, characterized in that, In step 3, the temperature for degumming is 800~850℃, and the degumming time is 2~4h.

8. The preparation method according to claim 2, characterized in that, In step 4, the temperature of the second sintering is 600~650℃, and the time of the second sintering is 30~60min.

9. The preparation method according to claim 2, characterized in that, In step 4, the high-voltage polarization includes polarizing in silicone oil at 120~160℃ with a polarization field strength of 3~5kV / mm for 15~30min.

10. The application of the PZT-based piezoelectric ceramic material as described in claim 1 in a high-temperature piezoelectric accelerometer.

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