Piezoelectric ceramic for new energy vehicle and preparation method thereof

Abstract

This invention relates to the field of piezoelectric ceramic materials, specifically to a piezoelectric ceramic for new energy vehicles and its preparation method, the general chemical formula of which is shown below: (1-α)(Li 0.5 Bi 0.5 ) x Ba 1‑x Ti 1‑ y Sn y O3-αBi 0.85 Nd 0.15 Fe 1‑z (Co 0.5 Al 0.5 ) z With 0 < x ≤ 0.2, 0 < y ≤ 0.1, 0 < z ≤ 0.5, and 0 < α ≤ 0.9, the piezoelectric ceramic prepared by this invention has excellent piezoelectric properties and has broad application potential in new energy vehicles.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of piezoelectric ceramic materials, in particular to a piezoelectric ceramic for new energy vehicles and a preparation method thereof. BACKGROUND

[0002] Piezoelectric ceramic materials have positive and negative piezoelectric effects, and are widely used in piezoelectric sensors, drivers, transducers and filters and other devices. The application range covers aerospace, information electronics, industrial machinery, medical treatment, automobiles and many other fields. As the information source of the automobile electronic control system, sensors are the key components of the automobile electronic control system. With the increasing degree of electronicization and automation of new energy vehicles, the dependence on sensors is also increasing. The number of sensors on an ordinary new energy vehicle can reach more than 200. As for piezoelectric ceramic sensors, common ones include piezoelectric ceramic knock sensors, ultrasonic sensors, acceleration sensors, etc.

[0003] With the deepening of the concept of environmental protection and social sustainable development, the demand for environmentally friendly lead-free piezoelectric materials is increasing. Among them, BiFeO3 is concerned due to its high Curie temperature, excellent electromagnetic performance and high energy density. However, the perovskite structure of BiFeO3 is unstable, and the insulating performance is poor, resulting in high leakage and loss, and it is difficult to fully polarize, so the piezoelectric performance is poor. By adding BaTiO3 to form a binary solid solution, the leakage current can be reduced, and a morphotropic phase boundary can be formed to obtain good electrical properties. Therefore, how to further improve the piezoelectric performance of BiFeO3-BaTiO3 to meet its application in new energy vehicles has become one of the research hotspots in the field. SUMMARY

[0004] The present application aims at the above technical problems and provides a piezoelectric ceramic for new energy vehicles and a preparation method thereof.

[0005] The technical scheme adopted is as follows:

[0006] A piezoelectric ceramic for new energy vehicles has the following chemical structure general formula:

[0007] (1-alpha)(Li 0.5 Bi 0.5 ) x Ba 1-x Ti 1-y Sn y O3-alphaBi 0.85 Nd 0.15 Fe 1-z (Co 0.5 Al 0.5 ) z O3

[0008] 0 < x < 0.2, 0 < y < 0.1, 0 < z < 0.5;

[0009] 0 < alpha < 0.9.

[0010] Further, 0.1 < x < 0.15, 0.04 < y < 0.06, 0.2 < z < 0.3.

[0011] Further, x = 0.12, y = 0.05, z = 0.25.

[0012] Further, 0.7 < alpha < 0.8.

[0013] Further, alpha = 0.75.

[0014] The application further provides a preparation method of the piezoelectric ceramic for new energy vehicles.

[0015] Li2CO3, Bi2O3, BaCO3, TiO2 and SnO2 are wet ball milled and dried to obtain first powder, the first powder is pre-fired to obtain first pre-fired material, Bi2O3, Nd2O3, Fe2O3, Al2O3 and Co2O3 are wet ball milled and dried to obtain second powder, the second powder is pre-fired to obtain second pre-fired material, the first pre-fired material and the second pre-fired material are mixed, wet ball milled again, dried, granulated, pressed into a green body, degassed and sintered.

[0016] Further, the pre-firing temperature of the first powder is 750-850 DEG C.

[0017] Further, the pre-firing temperature of the second powder is 750-850 DEG C.

[0018] Further, the pressure during pressing is 100-200 MPa.

[0019] Further, the sintering temperature is 1000-1100 DEG C.

[0020] The application has the following beneficial effects:

[0021] The application provides a piezoelectric ceramic for new energy vehicles, (Li 0.5 Bi 0.5 ) 2+ A-site doping of the BT ceramic can introduce lattice distortion, change the lattice symmetry and affect the resistance of domain flipping, thereby optimizing the piezoelectric performance. 4+ The radius of Sn is close to the radius of Ti in the B site of the BT ceramic, and the formation of a solid solution is expected to realize structure regulation and piezoelectric performance improvement. 4+

[0022] Nd 3+ ​As a trivalent rare earth metal ion, the doping can stabilize the BF ceramic lattice and has the effect of inhibiting the formation of oxygen vacancies. The bond energy of the Nd-O bond is higher than that of the Bi-O bond, which enhances the stability of the structure and reduces the oxygen vacancies caused by Bi volatilization. Therefore, the doping of Nd 3+ The doping can significantly reduce the leakage current of the BF ceramic, making the material more easily polarized, thereby having better piezoelectric properties. 0.5 Al 0.5 ) 3+ The doping can make the crystal structure of the BF-BT system change from rhombohedral to pseudo-cubic, and near the morphotropic phase boundary, the lattice is more easily reoriented under an external field, thereby significantly enhancing the piezoelectric response. The large leakage current of the BF ceramic is mainly caused by oxygen vacancies and the variable valence of Fe 3+ The doping of Al 3+ can stabilize oxygen ions and reduce the concentration of oxygen vacancies. The variable valence Co ion can exist in the form of Co 2+ / Co 3+ , and through the valence compensation mechanism, it can also inhibit the generation of Fe 2+ , thereby jointly reducing the leakage current and improving the breakdown field strength, so that the ceramic material can be polarized under a higher electric field and fully exhibit its piezoelectric potential.

[0023] The piezoelectric ceramic prepared by the application has excellent piezoelectric properties and has broad application potential in new energy vehicles. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 SEM image of the surface of the piezoelectric ceramic prepared in Example 1. DETAILED DESCRIPTION

[0025] Unless otherwise specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. Unless otherwise specified, the reagents or instruments used are conventional products that can be purchased on the market. The techniques not mentioned in the application refer to the prior art. Unless otherwise specified, the following examples and comparative examples are parallel tests using the same processing steps and parameters.

[0026] Example 1:

[0027] A piezoelectric ceramic for new energy vehicles has the following general chemical structure:

[0028] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 (Co0.5 Al 0.5 ) 0.25 O3

[0029] The above-mentioned preparation method of piezoelectric ceramics for new energy vehicles:

[0030] Li2CO3, Bi2O3, BaCO3, TiO2, and SnO2 were weighed according to their chemical formulas and added to a ball mill jar. The mixture was wet-milled in a planetary ball mill for 10 hours using anhydrous ethanol as the milling medium and then dried to obtain the first powder. The first powder was then pre-calcined at 800℃ for 3 hours to obtain the first pre-calcined material.

[0031] Bi2O3, Nd2O3, Fe2O3, Al2O3, and Co2O3 were weighed according to their chemical formulas and added to a ball mill jar. The mixture was wet-milled in a planetary ball mill for 10 hours using anhydrous ethanol as the milling medium and then dried to obtain a second powder. The second powder was then pre-calcined at 800℃ for 3 hours to obtain a second pre-calcined material.

[0032] The first and second pre-calcined materials were mixed and added to a ball mill jar. The mixture was wet-milled in a planetary ball mill for 6 hours using anhydrous ethanol as the milling medium. After drying, a 10% polyvinyl alcohol solution (8% of the powder mass) was added to mix and granulate. The resulting granules were pressed into green bodies in a mold at 100 MPa. The green bodies were debinded at 550℃ for 2 hours and then returned to room temperature. They were then transferred to a sintering furnace and sintered at 1050℃ for 3 hours at a rate of 5℃ / min. Figure 1 The image shows the SEM image of the piezoelectric ceramic surface prepared in this embodiment. It can be seen that it exhibits a dense microstructure, with no obvious pores, and the grain size is uniform with no abnormally large grains.

[0033] Example 2:

[0034] A piezoelectric ceramic for new energy vehicles has the following general chemical structure formula:

[0035] 0.25 (Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3

[0036] The above-mentioned preparation method of piezoelectric ceramics for new energy vehicles:

[0037] Li2CO3, Bi2O3, BaCO3, TiO2, SnO2 are weighed according to the chemical formula and added to the ball mill tank, and after wet ball milling in the planetary ball mill for 10h with anhydrous ethanol as the ball milling medium, the first powder is dried, and the first pre-fired material is obtained after pre-firing the first powder at 850℃ for 2h;

[0038] Bi2O3, Nd2O3, Fe2O3, Al2O3, Co2O3 are weighed according to the chemical formula and added to the ball mill tank, and after wet ball milling in the planetary ball mill for 10h with anhydrous ethanol as the ball milling medium, the second powder is dried, and the second pre-fired material is obtained after pre-firing the second powder at 850℃ for 2h;

[0039] The first pre-fired material and the second pre-fired material are mixed and added to the ball mill tank, and after wet ball milling in the planetary ball mill for 6h with anhydrous ethanol as the ball milling medium, the mixture is dried, a polyvinyl alcohol solution with a mass fraction of 10% (the amount used is 8% of the mass of the powder) is added and mixed to form granules, the granules are pressed into a green body in a mold at 100MPa, the green body is degassed at 550℃ for 2h and then cooled to room temperature, and then transferred to a sintering furnace and sintered at a rate of 5℃ / min to 1100℃ for 2h.

[0040] Example 3:

[0041] A piezoelectric ceramic for new energy vehicles has the following general chemical structure:

[0042] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3

[0043] A preparation method of the piezoelectric ceramic for new energy vehicles:

[0044] Li2CO3, Bi2O3, BaCO3, TiO2, SnO2 are weighed according to the chemical formula and added to the ball mill tank, and after wet ball milling in the planetary ball mill for 10h with anhydrous ethanol as the ball milling medium, the first powder is dried, and the first pre-fired material is obtained after pre-firing the first powder at 750℃ for 4h;

[0045] Bi2O3, Nd2O3, Fe2O3, Al2O3, Co2O3 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10 h with anhydrous ethanol as the ball milling medium, the second powder is dried, and after pre-sintering the second powder at 750 DEG C for 4 h, the second pre-sintered material is obtained;

[0046] The first pre-sintered material and the second pre-sintered material are mixed and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 6 h with anhydrous ethanol as the ball milling medium, the mixture is dried, a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) is added and mixed to form granules, the granules are pressed into a green body in a mold at 100 MPa, the green body is degassed at 550 DEG C for 2 h and then restored to room temperature, and then transferred to a sintering furnace and sintered at a speed of 5 DEG C / min to 1000 DEG C for 4 h.

[0047] Comparative Example 1:

[0048] The same as Example 1, except that (Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 TiO3 is replaced by (Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3.

[0049] A piezoelectric ceramic for a new energy vehicle, which has a chemical structure general formula as follows:

[0050] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 TiO3-0.75Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3

[0051] A preparation method of the piezoelectric ceramic for a new energy vehicle:

[0052] Li2CO3, Bi2O3, BaCO3, TiO2 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10 h with anhydrous ethanol as the ball milling medium, the first powder is dried, and after pre-sintering the first powder at 800 DEG C for 3 h, the first pre-sintered material is obtained;

[0053] Bi2O3, Nd2O3, Fe2O3, Al2O3, Co2O3 are weighed according to the chemical formula and added into the ball mill tank, and after wet ball milling in the planetary ball mill for 10 h with anhydrous ethanol as the ball milling medium, the second powder is dried, and the second pre-fired material is obtained after pre-firing the second powder at 800 ℃ for 3 h;

[0054] The first pre-fired material and the second pre-fired material are mixed and added into the ball mill tank, and after wet ball milling in the planetary ball mill for 6 h with anhydrous ethanol as the ball milling medium, the mixture is dried, a polyvinyl alcohol solution with a mass fraction of 10% (an amount of 8% of the mass of the powder) is added and mixed to form granules, the granules are pressed into a green body in a mold at 100 MPa, the green body is degassed at 550 ℃ for 2 h and then restored to room temperature, and then transferred to a sintering furnace and sintered at 1050 ℃ for 3 h at a speed of 5 ℃ / min.

[0055] Comparative Example 2:

[0056] The same as Example 1, except that BaTi 0.95 Sn 0.05 O3 is used instead of (Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3.

[0057] A piezoelectric ceramic for new energy vehicles, which has a chemical structure represented by the general formula:

[0058] 0.25BaTi 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3

[0059] A preparation method of the piezoelectric ceramic for new energy vehicles:

[0060] BaCO3, TiO2, and SnO2 are weighed according to the chemical formula and added into the ball mill tank, and after wet ball milling in the planetary ball mill for 10 h with anhydrous ethanol as the ball milling medium, the first powder is dried, and the first pre-fired material is obtained after pre-firing the first powder at 800 ℃ for 3 h;

[0061] Bi2O3, Nd2O3, Fe2O3, Al2O3, Co2O3 are weighed according to the chemical formula and added into the ball mill tank, and after wet ball milling in the planetary ball mill for 10 h with anhydrous ethanol as the ball milling medium, the second powder is dried, and the second pre-fired material is obtained after pre-firing the second powder at 800 ℃ for 3 h;

[0062] The first pre-sintering material and the second pre-sintering material are mixed and added to a ball mill tank, and after wet ball milling in a planetary ball mill for 6h with anhydrous ethanol as a ball milling medium, drying, adding a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) and mixing and granulating, the obtained granules are pressed into a green body in a mold at 100MPa, the green body is deformed at 550℃ for 2h and then restored to room temperature, and then transferred to a sintering furnace and sintered at a speed of 5℃ / min to 1050℃ for 3h.

[0063] Comparative Example 3:

[0064] The same as Example 1, except that Bi 0.85 Nd 0.15 FeO3 is replaced by Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3.

[0065] A piezoelectric ceramic for a new energy vehicle has a general chemical structure as shown in the following formula:

[0066] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 FeO3

[0067] A preparation method of the piezoelectric ceramic for a new energy vehicle is provided.

[0068] Li2CO3, Bi2O3, BaCO3, TiO2 and SnO2 are weighed according to the chemical formula and added to a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a first powder, and the first powder is pre-sintered at 800℃ for 3h to obtain a first pre-sintering material;

[0069] Bi2O3, Nd2O3 and Fe2O3 are weighed according to the chemical formula and added to a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a second powder, and the second powder is pre-sintered at 800℃ for 3h to obtain a second pre-sintering material;

[0070] The first pre-sintering material and the second pre-sintering material are mixed and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 6h with anhydrous ethanol as a ball milling medium, drying, adding a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) and mixing and granulating, the obtained granules are pressed into a green body in a mold at 100MPa, the green body is deformed at 550℃ for 2h and then restored to room temperature, and then transferred to a sintering furnace and sintered at a speed of 5℃ / min to 1050℃ for 3h.

[0071] Comparative Example 4:

[0072] The same as Example 1, except that BiFe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3 is replaced by Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3.

[0073] A piezoelectric ceramic for a new energy vehicle has a general chemical structure as shown in the following formula:

[0074] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75BiFe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3

[0075] A preparation method of the piezoelectric ceramic for a new energy vehicle is provided.

[0076] Li2CO3, Bi2O3, BaCO3, TiO2 and SnO2 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a first powder, and the first powder is pre-sintered at 800℃ for 3h to obtain a first pre-sintering material;

[0077] Bi2O3, Fe2O3, Al2O3 and Co2O3 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a second powder, and the second powder is pre-sintered at 800℃ for 3h to obtain a second pre-sintering material;

[0078] The first pre-sintering material and the second pre-sintering material are mixed and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 6h with anhydrous ethanol as a ball milling medium, drying, adding a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) and mixing and granulating, the obtained granules are pressed into a green body in a mold at 100MPa, the green body is deformed at 550℃ for 2h and then restored to room temperature, and then transferred to a sintering furnace and sintered at a speed of 5℃ / min to 1050℃ for 3h.

[0079] Comparative Example 5:

[0080] The same as Example 1, except that Bi 0.85 Nd 0.15 Fe 0.75 Co 0.25 O3 is replaced by Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3.

[0081] A piezoelectric ceramic for a new energy vehicle has a general chemical structure as shown in the following formula:

[0082] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 Co 0.25 O3

[0083] A preparation method of the piezoelectric ceramic for a new energy vehicle is provided.

[0084] Li2CO3, Bi2O3, BaCO3, TiO2 and SnO2 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a first powder, and the first powder is pre-sintered at 800℃ for 3h to obtain a first pre-sintering material;

[0085] Bi2O3, Nd2O3, Fe2O3 and Co2O3 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a second powder, and the second powder is pre-sintered at 800℃ for 3h to obtain a second pre-sintering material;

[0086] The first pre-sintering material and the second pre-sintering material are mixed and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 6h with anhydrous ethanol as a ball milling medium, drying, adding a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) and mixing and granulating, the obtained granules are pressed into a green body in a mold at 100MPa, the green body is deformed at 550℃ for 2h and then restored to room temperature, and then transferred to a sintering furnace and sintered at a speed of 5℃ / min to 1050℃ for 3h.

[0087] Comparative Example 6:

[0088] The same as Example 1, except that Bi 0.85 Nd 0.15 Fe 0.75 Al 0.25 O3 is replaced by Bi 0.85 Nd 0.15 Fe 0.75 (Co 0.5 Al 0.5 ) 0.25 O3.

[0089] A piezoelectric ceramic for a new energy vehicle has a general chemical structure as shown in the following formula:

[0090] 0.25(Li 0.5 Bi 0.5 ) 0.12 Ba 0.88 Ti 0.95 Sn 0.05 O3-0.75Bi 0.85 Nd 0.15 Fe 0.75 Al 0.25 O3

[0091] A preparation method of the piezoelectric ceramic for a new energy vehicle is provided.

[0092] Li2CO3, Bi2O3, BaCO3, TiO2 and SnO2 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a first powder, and the first powder is pre-sintered at 800℃ for 3h to obtain a first pre-sintering material;

[0093] Bi2O3, Nd2O3, Fe2O3 and Al2O3 are weighed according to the chemical formula and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 10h with anhydrous ethanol as a ball milling medium, drying is performed to obtain a second powder, and the second powder is pre-sintered at 800℃ for 3h to obtain a second pre-sintering material;

[0094] The first pre-sintering material and the second pre-sintering material are mixed and added into a ball mill tank, and after wet ball milling in a planetary ball mill for 6 hours with anhydrous ethanol as a ball milling medium, drying, adding a polyvinyl alcohol solution with a mass fraction of 10% (the amount is 8% of the mass of the powder) to mix and granulate, the obtained granules are pressed into a blank in a mold at 100 MPa, the blank is deformed at 550 DEG C for 2 hours, then restored to room temperature, and then transferred to a sintering furnace to be sintered at a speed of 5 DEG C / min to 1050 DEG C for 3 hours.

[0095] Performance test:

[0096] The surface of the piezoelectric ceramic prepared in examples 1-3 and comparative examples 1-6 is polished respectively, and silver paste is coated on both sides, and silver is burned at 600 DEG C for 30 min, and finally the sample is polarized in silicon oil at 100 DEG C under a direct current voltage of 4.5 kV / mm for 10 min, and then placed for 24 h to test the performance.

[0097] Piezoelectric constant d 33 Measured by a quasi-static piezoelectric coefficient measuring instrument (ZJ-3A type of the Chinese Academy of Sciences) at room temperature.

[0098] The electromechanical coupling coefficient kp, the mechanical quality factor Qm and the dielectric loss tan delta (25 DEG C, 1v, 1 kHz) are measured based on the resonance-anti-resonance method using a precision impedance analyzer (Agilent-4294A);

[0099] The test results are shown in Table 1 as follows:

[0100] Table 1:

[0101]

[0102] From Table 1 above, it can be seen that the piezoelectric ceramic prepared by the application has excellent piezoelectric performance.

[0103] It can be known by comparing example 1 with comparative example 1 that Sn 4+ Doping plays a positive role in improving the piezoelectric performance of the piezoelectric ceramic.

[0104] It can be known by comparing example 1 with comparative example 2 that (Li 0.5 Bi 0.5 ) 2+ Doping plays a positive role in improving the piezoelectric performance of the piezoelectric ceramic.

[0105] It can be known by comparing example 1 with comparative example 3 that (Co 0.5 Al 0.5 ) 3+ Doping plays a positive role in improving the piezoelectric performance of the piezoelectric ceramic.

[0106] By comparing Example 1 with Comparative Example 4, it can be seen that Nd 3+ Doping plays a positive role in improving the piezoelectric performance of piezoelectric ceramics.

[0107] By comparing Example 1 with Comparative Example 5, it can be seen that Al 3+ Doping plays a positive role in improving the piezoelectric performance of piezoelectric ceramics.

[0108] By comparing Example 1 with Comparative Example 6, it can be seen that Co 3+ Doping plays a positive role in improving the piezoelectric performance of piezoelectric ceramics.

[0109] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that the technical solutions recorded in the foregoing examples can be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A piezoelectric ceramic for new energy vehicles, characterized in that, The chemical structure general formula is shown as follows: (1 - α)(Li 0.5 Bi 0.5 ) x Ba 1-x Ti 1-y Sn y O3 - αBi 0.85 Nd 0.15 Fe 1-z (Co 0.5 Al 0.5 ) z O3 0 < x < 0.2, 0 < y < 0.1, 0 < z < 0.5; 0＜α≤0.9。 2. The piezoelectric ceramic for new energy vehicles according to claim 1, characterized in that, 0.1 < x < 0.15, 0.04 < y < 0.06, 0.2 < z < 0.

3.

3. The piezoelectric ceramic for new energy vehicles according to claim 1, characterized in that, x = 0.12, y = 0.05, z = 0.

25.

4. The piezoelectric ceramic for new energy vehicles according to claim 1, characterized in that, 0.7≤α≤0.8。 5. The piezoelectric ceramic for new energy vehicles according to claim 1, characterized in that, α=0.75。 6. A method of producing a piezoelectric ceramic for a new energy vehicle according to any one of claims 1 to 5, characterized by, Specifically as follows: Li2CO3, Bi2O3, BaCO3, TiO2, SnO2 are wet ball-milled and dried to obtain a first powder, the first powder is pre-fired to obtain a first pre-fired material, Bi2O3, Nd2O3, Fe2O3, Al2O3, Co2O3 are wet ball-milled and dried to obtain a second powder, the second powder is pre-fired to obtain a second pre-fired material, the first pre-fired material and the second pre-fired material are mixed, wet ball-milled again, dried, granulated, pressed into a green body, degassed and sintered.

7. The method for preparing piezoelectric ceramics for new energy vehicles according to claim 6, characterized in that, The pre-firing temperature of the first powder is 750-850℃. 8.The method for preparing piezoelectric ceramics for new energy vehicles according to claim 6, characterized in that, The pre-firing temperature of the second powder is 750-850℃.

9. The method for preparing piezoelectric ceramics for new energy vehicles according to claim 6, characterized in that, The pressure during pressing is 100-200MPa.

10. The method for preparing piezoelectric ceramics for new energy vehicles according to claim 6, characterized in that, The sintering temperature is 1000-1100℃.

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