Temperature-stable multiphase ceramic material for high-temperature capacitor and preparation method of temperature-stable multiphase ceramic material

Abstract

The invention discloses a temperature-stable multiphase ceramic material for a high-temperature capacitor and a preparation method of the temperature-stable multiphase ceramic material. The method comprises the following steps: weighing Na < 0.465 > Li < 0.07 > Bi < 0.465 > Ta < 0.07 > Ti < 0.93 > O < 3-x > BaLa < 2 > Ti < 4 > O < 12 > according to a stoichiometric formula (1-x) Na < 0.465 > Li < 0.07 > Bi < 0.465 > Ta < 0.07 > Ti < 0.93 > O < 3-x > BaLa < 2 > Ti < 4 > O < 12 >, x is greater than or equal to 0.01 and less than or equal to 0.05, and uniformly mixing to form a full ingredient; carrying out ball milling, drying and sieving on the full ingredients to form sieved materials; and pressing the sieved material into a green body, and sintering the green body to obtain the temperature-stable composite ceramic. The problems that an existing NBT-based ceramic material is large in leakage current, low in breakdown field strength and low in efficiency at the high temperature are solved. According to the ceramic material prepared by the method, the low-loss microwave dielectric ceramic material barium lanthanum titanate is introduced, oxygen vacancies generated by volatilization of Na < + > and Bi < 3 + > in the sintering process are compensated, stable charge accumulation is formed at the interface of the ceramic material and a main phase, ion migration activation energy at a grain boundary is reduced, and the performance of the ceramic material is improved. The change of the dielectric loss tangent value tan delta along with the temperature tends to be gentle, the polarization response of the ferroelectric domain is further inhibited, and the dielectric property is stabilized.

Description

Technical Field

[0001] This invention relates to the field of high-temperature stable multiphase ceramic capacitors, and specifically to a temperature-stable multiphase ceramic material for high-temperature capacitors and its preparation method. Background Technology

[0002] Due to their excellent high-temperature stability and dielectric properties, NBT-based ceramic materials are widely used in the manufacture of high-temperature capacitors. Sodium bismuth titanate (Na.Bi.TiO) (NBT) materials exhibit strong ferroelectricity and weak relaxation, manifested in their broad and "fat" hysteresis loop and high remanent polarization (P). r Its energy storage efficiency (W) is relatively high. However, this characteristic leads to a lower energy storage efficiency (W). rec The oxygen vacancy rate is relatively low (typically below 70%), and during charge-discharge cycles, a significant amount of energy is dissipated as heat (i.e., hysteresis loss). Furthermore, at high temperatures, oxygen vacancies in the NBT... Activation migration and Na + 、 Bi 3+ The volatilization and migration of these substances cause a sharp decrease in volume resistivity and a significant increase in leakage current. These factors become key bottlenecks limiting the actual operating field strength and the breakdown field strength at high temperatures, severely restricting its energy storage density and reliability. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention aims to provide a temperature-stable multiphase ceramic material for high-temperature capacitors and its preparation method, which solves the problems of large leakage current, low breakdown field strength and reduced efficiency of existing NBT-based ceramic materials at high temperatures.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows:

[0005] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula: (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 , where 0.01≤x≤0.05.

[0006] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0007] Step 1: According to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O12 0.01≤x≤0.05, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0008] Step 2: The complete batch of ingredients is ball-milled, dried, and sieved to form sieved material;

[0009] Step 3: Press the sieved material into a green body, and sinter the green body to obtain a temperature-stable multiphase ceramic.

[0010] Furthermore, in step 1, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder is obtained through the following steps:

[0011] Weigh Na2CO3, Bi2O3 and TiO2 according to a molar ratio of 1:1:(3.5-4.5) and mix them to form mixture A. Take mixture A, zircon and deionized water and mix them according to a mass ratio of 1:(4.8-5.2):(0.8-1.2). Then, ball mill, dry and calcine at 850-860℃ for 3-4 hours to obtain powder B.

[0012] Powder B was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0013] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of (0.8-1.2):(0.8-1.2) to form mixture C. Mixture C, zircon, and deionized water were then mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), followed by ball milling, drying, and calcination at 850-860℃ for 3-4 hours to obtain powder D.

[0014] The powder D was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain LiTaO3 powder.

[0015] Weigh the Na according to the molar ratio (92-94):(6-8). 0.5Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried and calcined at 850-860℃ for 3-4 hours to obtain powder F.

[0016] The powder F was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0017] Furthermore, in step 1, BaLa2Ti4O 12 The powder is obtained through the following steps:

[0018] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:(3.5-4.5) to form a mixture G. The mixture G, zircon and deionized water were mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2) and then ball-milled, dried and calcined at 1050-1150℃ for 3-4 hours to obtain powder H.

[0019] The powder H was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 1050-1150℃ for 3-4 hours to obtain BaLa2Ti4O. 12 .

[0020] Further, in step 2, the whole batch of ingredients is mixed with zircon and deionized water at a mass ratio of 1:(4.8-5.2):(0.8-1.2), then ball-milled and dried.

[0021] Furthermore, the ball milling process lasts 12-24 hours, followed by drying at 85-100℃ for 24 hours.

[0022] Furthermore, the mesh size of the sieve used in step 2 is 140-160 mesh.

[0023] Furthermore, the pressing process in step 3 specifically involves holding the pressure at 180-220 MPa for 2-4 minutes, then holding the pressure at 170-200 MPa for 4-6 minutes, and finally releasing the pressure at 30-50 MPa / min to form a blank through cold isostatic pressing.

[0024] Furthermore, the sintering in step 3 specifically involves first heating the furnace to 1100-1150°C for 210-230 minutes, holding the temperature for 1.5-2.5 hours, then cooling the furnace to 480-520°C for 110-130 minutes, and finally cooling the furnace to room temperature.

[0025] Compared with the prior art, the present invention has the following beneficial technical effects:

[0026] (1-x)Na prepared by the method of the present invention 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 Ceramic materials, through the introduction of low-loss microwave dielectric ceramic material barium lanthanum titanate (BaLa2Ti4O) 12 ), compensation due to Na during sintering + Bi 3 + The oxygen vacancies generated by volatilization form stable charge accumulation at the interface with the main phase, reducing the activation energy of ion migration at grain boundaries. This causes the dielectric loss tangent (tanδ) to change more gradually with temperature, further suppressing the polarization response of ferroelectric domains and stabilizing dielectric properties. Not only does it possess high-temperature stability, a high dielectric constant, and low dielectric loss and relaxation characteristics, but its preparation process is also simple, the material cost is low, and it is environmentally friendly. Therefore, it has become an important candidate material that offers both technical and economic advantages in replacing lead-based ceramic materials for high-end industrial applications. Attached Figure Description

[0027] Figure 1 The XRD patterns of the ceramic materials prepared in Examples 1-5 of this invention are shown below.

[0028] Figure 2 This is a comparison chart of the dielectric constants of the ceramic materials prepared in Examples 1-5 of this invention at 1MHz;

[0029] Figure 3 The temperature stability (T) of the ceramic materials prepared in Examples 1-5 of this invention. cc Comparison chart. Detailed Implementation

[0030] The embodiments of the present invention will be described in further detail below:

[0031] The purity of Na2CO3, Bi2O3, TiO2, Li2CO3, Ta2O5, BaCO3, and La2O3 mentioned below is all above 99.0%, and a planetary ball mill is used for ball milling.

[0032] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 , 0.01≤x≤0.05.

[0033] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0034] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 0.01≤x≤0.05, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0035] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0036] Weigh out Na₂CO₃, Bi₂O₃, and TiO₂ in a molar ratio of 1:1:(3.5-4.5). 2， Mixing forms a mixture A. Mixture A, zircon, and deionized water are mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain powder B.

[0037] Powder B was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.5 Bi 0.5TiO3 powder;

[0038] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of (0.8-1.2):(0.8-1.2) to form mixture C. Mixture C, zircon, and deionized water were then mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), followed by ball milling, drying, and calcination at 850-860℃ for 3-4 hours to obtain powder D.

[0039] The powder D was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain LiTaO3 powder.

[0040] Weigh the Na according to the molar ratio (92-94):(6-8). 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried and calcined at 850-860℃ for 3-4 hours to obtain powder F.

[0041] The powder F was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0042] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0043] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:(3.5-4.5) to form a mixture G. The mixture G, zircon and deionized water were mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2) and then ball-milled, dried and calcined at 1050-1150℃ for 3-4 hours to obtain powder H.

[0044] The powder H was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 1050-1150℃ for 3-4 hours to obtain BaLa2Ti4O1.

[0045] The ball milling time mentioned above is 12 hours, followed by drying at 85-100℃ for 24 hours;

[0046] Step 2: Mix the prepared ingredients with zircon and deionized water at a mass ratio of 1:(4.8-5.2):(0.8-1.2), then ball mill and dry the mixture. Grind the dried material through a 140-160 mesh sieve.

[0047] The ball milling process described in steps 1 and 2 above lasts for 12-24 hours, followed by drying at 85-100℃ for 24 hours.

[0048] Step 3: The sieved material is first pressed at 180-220MPa for 2-4 minutes, then pressed at 170-200MPa for 4-6 minutes, and finally depressurized at 30-50MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100-1150℃ at 210-230min and held for 1.5-2.5h, then cooled to 480-520℃ at 110-130min and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0049] The ball milling process lasts 12-24 hours, followed by drying at 85-100℃ for 24 hours.

[0050] The present invention will be further described in detail below with reference to embodiments. However, it should be understood that the following specific embodiments are merely further elaborations on the present invention and not further limitations thereof:

[0051] Example 1

[0052] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.01.

[0053] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0054] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93O3-xBaLa2Ti4O 12 x = 0.01, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0055] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0056] Na₂CO₃, Bi₂O₃, and TiO₂ were weighed according to a molar ratio of 1:1:4. 2， Mixture A is formed by mixing. Mixture A, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder B.

[0057] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0058] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5:1 and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain powder D.

[0059] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0060] The Na was weighed according to a molar ratio of 93:7. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder F.

[0061] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465Ta 0.07 Ti 0.93 O3 powder.

[0062] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0063] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:5:1. The mixture was then ball-milled, dried and calcined at 1110℃ for 4 hours to obtain powder H.

[0064] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 1110℃ for 4 hours to obtain BaLa2Ti4O. 12 ;

[0065] Step 2: Mix the prepared ingredients with zircon and deionized water in a mass ratio of 1:5:1, then ball mill and dry the mixture. Grind the dried material through a 150-mesh sieve.

[0066] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 85°C for 24 hours;

[0067] Step 3: The sieved material is first pressed at 220MPa for 2 minutes, then pressed at 170MPa for 4 minutes, and finally depressurized at 30MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100℃ for 222 minutes and held for 2 hours, then cooled to 500℃ for 122 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0068] The sintered sample obtained in step 3 (grinding and cleaning) was coated with silver electrode paste evenly on both sides. The sample coated with silver electrodes was placed in an alumina crucible with zirconium oxide as a backing plate. The alumina crucible was then placed in a box furnace and sintered at 650°C for 24 min to obtain 0.99Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-0.01BaLa2Ti4O 12 ceramics.

[0069] Example 2

[0070] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti0.93 O3-xBaLa2Ti4O 12 x = 0.02.

[0071] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0072] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.02, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0073] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0074] Na₂CO₃, Bi₂O₃, and TiO₂ were weighed according to a molar ratio of 1:1:4. 2， Mixture A is formed by mixing. Mixture A, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder B.

[0075] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0076] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5:1 and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain powder D.

[0077] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0078] The Na was weighed according to a molar ratio of 93:7. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form a mixture

[0079] Compound E, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder F;

[0080] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0081] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0082] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:5:1. The mixture was then ball-milled, dried and calcined at 1110℃ for 4 hours to obtain powder H.

[0083] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 1110℃ for 4 hours to obtain BaLa2Ti4O. 12 ;

[0084] Step 2: Mix the prepared ingredients with zircon and deionized water in a mass ratio of 1:5:1, then ball mill and dry the mixture. Grind the dried material through a 150-mesh sieve.

[0085] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 85°C for 24 hours;

[0086] Step 3: The sieved material is first pressed at 220MPa for 2 minutes, then pressed at 170MPa for 4 minutes, and finally depressurized at 30MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100℃ for 222 minutes and held for 2 hours, then cooled to 500℃ for 122 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0087] The sintered sample obtained in step 3 (grinding and cleaning) was then uniformly coated with silver electrode paste on both sides. The silver-coated sample was placed in an alumina crucible with a zirconium oxide pad, and then the alumina crucible was placed in a box furnace and sintered at 650°C for 24 minutes to obtain 0.98Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-0.02BaLa2Ti4O 12 ceramics.

[0088] Example 3

[0089] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.03.

[0090] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0091] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.03, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0092] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0093] Na₂CO₃, Bi₂O₃, and TiO₂ were weighed according to a molar ratio of 1:1:4. 2， Mixture A is formed by mixing. Mixture A, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder B.

[0094] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0095] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5:1 and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain powder D.

[0096] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0097] The Na was weighed according to a molar ratio of 93:7. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder F.

[0098] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0099] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0100] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:5:1. The mixture was then ball-milled, dried and calcined at 1110℃ for 4 hours to obtain powder H.

[0101] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 1110℃ for 4 hours to obtain BaLa2Ti4O. 12 ;

[0102] Step 2: Mix the prepared ingredients with zircon and deionized water in a mass ratio of 1:5:1, then ball mill and dry the mixture. Grind the dried material through a 150-mesh sieve.

[0103] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 85°C for 24 hours;

[0104] Step 3: The sieved material is first pressed at 220MPa for 2 minutes, then pressed at 170MPa for 4 minutes, and finally depressurized at 30MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100℃ for 222 minutes and held for 2 hours, then cooled to 500℃ for 122 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0105] The sintered sample obtained in step 3 (grinding and cleaning) was coated with silver electrode paste evenly on both sides. The sample coated with silver electrodes was then placed in an alumina crucible with zirconium oxide as a backing plate. The alumina crucible was then placed in a box furnace and sintered at 650°C for 24 min to obtain 0.97Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-0.03BaLa2Ti4O 12 ceramics.

[0106] Example 4

[0107] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.04.

[0108] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0109] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.04, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0110] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0111] Na₂CO₃, Bi₂O₃, and TiO₂ were weighed according to a molar ratio of 1:1:4. 2， Mixture A is formed by mixing. Mixture A, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder B.

[0112] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0113] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5:1 and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain powder D.

[0114] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0115] The Na was weighed according to a molar ratio of 93:7. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder F.

[0116] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0117] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0118] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:5:1. The mixture was then ball-milled, dried and calcined at 1110℃ for 4 hours to obtain powder H.

[0119] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 1110℃ for 4 hours to obtain BaLa2Ti4O. 12 ;

[0120] Step 2: Mix the prepared ingredients with zircon and deionized water in a mass ratio of 1:5:1, then ball mill and dry the mixture. Grind the dried material through a 150-mesh sieve.

[0121] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 85°C for 24 hours;

[0122] Step 3: The sieved material is first pressed at 220MPa for 2 minutes, then pressed at 170MPa for 4 minutes, and finally depressurized at 30MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100℃ for 222 minutes and held for 2 hours, then cooled to 500℃ for 122 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0123] The sintered sample obtained in step 3 (grinding and cleaning) was coated with silver electrode paste evenly on both sides. The sample coated with silver electrodes was placed in an alumina crucible with zirconium oxide as a backing plate. The alumina crucible was then placed in a box furnace and sintered at 650°C for 24 min to obtain 0.96Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-0.04BaLa2Ti4O 12 ceramics.

[0124] Example 5

[0125] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.05.

[0126] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0127] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.05, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0128] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0129] Na₂CO₃, Bi₂O₃, and TiO₂ were weighed according to a molar ratio of 1:1:4. 2， Mixture A is formed by mixing. Mixture A, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder B.

[0130] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0131] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5:1 and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain powder D.

[0132] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0133] The Na was weighed according to a molar ratio of 93:7. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:5:1 and then ball-milled, dried and calcined at 850°C for 4 hours to obtain powder F.

[0134] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 850°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0135] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0136] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:5:1. The mixture was then ball-milled, dried and calcined at 1110℃ for 4 hours to obtain powder H.

[0137] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5:1, and then ball-milled, dried, and calcined at 1110℃ for 4 hours to obtain BaLa2Ti4O. 12 ;

[0138] Step 2: Mix the prepared ingredients with zircon and deionized water in a mass ratio of 1:5:1, then ball mill and dry the mixture. Grind the dried material through a 150-mesh sieve.

[0139] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 85°C for 24 hours;

[0140] Step 3: The sieved material is first pressed at 220MPa for 2 minutes, then pressed at 170MPa for 4 minutes, and finally depressurized at 30MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1100℃ for 222 minutes and held for 2 hours, then cooled to 500℃ for 122 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0141] The sintered sample obtained in step 3, after grinding and cleaning, was uniformly coated with silver electrode paste on both sides. The sample coated with silver electrodes was then placed in an alumina crucible with zirconium oxide as a backing plate. The alumina crucible was then placed in a box furnace and sintered at 650°C for 24 min to obtain 0.95Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-0.05BaLa2Ti4O 12 ceramics.

[0142] XRD tests were performed on the samples prepared in Examples 1-5 to obtain... Figure 1 result, Figure 1 is (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 XRD patterns of the ceramic system. From Figure 1 It can be seen that the synthesized ceramic sample exhibits a typical perovskite phase structure, and the dopant BLTO successfully diffuses into Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 In the O3 lattice, a continuous solid solution phase is formed. As the BLTO doping concentration increases, XRD detects the formation of the Bi2Ti2O7 phase, which originates from the side reactions of Bi, Ta, and Ti elements during the high-temperature sintering process.

[0143] Figure 2 is (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 The dielectric constant of the ceramic samples changes with temperature. As the amount of BLTO added increases, the dielectric constant of the ceramic samples first increases and then decreases, and the dielectric double peak shifts towards lower temperatures, indicating that the addition of BLTO is beneficial to improving the dielectric temperature stability of NBT-based ceramics.

[0144] Figure 3 is (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 Temperature stability of ceramic samples (T) cc ).from Figure 3 It can be seen that all ceramic samples exhibit excellent dielectric temperature stability. Ceramic samples with x = 0.01-0.05 have a wide operating temperature range (50-500℃), satisfying T... cc A variation requirement of ≤±15%. Even if the standard is raised to T... cc The dielectric-temperature stability range of ceramic samples with x = 0.02-0.05 remains very wide, with a tolerance of ≤ ±10%.

[0145] Example 6

[0146] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.02.

[0147] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0148] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.02, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0149] Among them, Na0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0150] Weigh out Na₂CO₃, Bi₂O₃, and TiO₂ according to a molar ratio of 1:1:3.5. 2， Mixtures are combined to form mixture A. Mixture A, zircon, and deionized water are mixed in a mass ratio of 1:4.8:0.8 and then ball-milled, dried, and calcined at 855°C for 3 hours to obtain powder B.

[0151] Powder B was mixed with zircon and deionized water in a mass ratio of 1:4.8:0.8, and then ball-milled, dried, and calcined at 855°C for 3 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0152] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 0.8:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:4.8:0.8 and then ball-milled, dried, and calcined at 855°C for 3 hours to obtain powder D.

[0153] The powder D was mixed with zircon and deionized water in a mass ratio of 1:4.8:0.8, and then ball-milled, dried and calcined at 855°C for 3 hours to obtain LiTaO3 powder.

[0154] The Na was weighed according to a molar ratio of 92:8. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:4.8:0.8 and then ball-milled, dried and calcined at 855°C for 3 hours to obtain powder F.

[0155] The powder F was mixed with zircon and deionized water in a mass ratio of 1:4.8:0.8, and then ball-milled, dried, and calcined at 855°C for 3 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

[0156] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0157] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:3.5 to form mixture G. Mixture G, zircon and deionized water were taken and mixed in a mass ratio of 1:4.8:0.8. The mixture was then ball-milled, dried and calcined at 1050℃ for 3 hours to obtain powder H.

[0158] The powder H was mixed with zircon and deionized water in a mass ratio of 1:4.8:0.8, and then ball-milled, dried, and calcined at 1050°C for 3 hours to obtain BaLa2Ti4O. 12 ;

[0159] Step 2: Mix the prepared ingredients with zircon and deionized water at a mass ratio of 1:4.8:0.8, then ball mill and dry the mixture. Grind the dried material through a 140-mesh sieve.

[0160] The ball milling time described in steps 1 and 2 above is 18 hours, followed by drying at 90°C for 24 hours;

[0161] Step 3: The sieved material is first pressed at 180MPa for 3 minutes, then at 190MPa for 5 minutes, and finally depressurized at 40MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1125℃ in 210 minutes and held for 1.5 hours, then lowered to 480℃ in 110 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

[0162] Example 7

[0163] A temperature-stable multiphase ceramic material for high-temperature capacitors, with the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 x = 0.03.

[0164] A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors includes the following steps:

[0165] Step 1: Preparation of Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder, BaLa2Ti4O 12 Powder, according to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O12 x = 0.03, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients;

[0166] Among them, Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 The preparation of O3 powder is as follows:

[0167] Weigh out Na₂CO₃, Bi₂O₃, and TiO₂ in a molar ratio of 1:1:4.5. 2， Mixture A is formed by mixing. Mixture A, zircon, and deionized water are mixed in a mass ratio of 1:5.2:1.2 and then ball-milled, dried, and calcined at 860°C for 4 hours to obtain powder B.

[0168] Powder B was mixed with zircon and deionized water in a mass ratio of 1:5.2:1.2, and then ball-milled, dried, and calcined at 860°C for 4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder;

[0169] Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of 1:1 to form mixture C. Mixture C, zircon, and deionized water were mixed in a mass ratio of 1:5.2:1.2 and then ball-milled, dried, and calcined at 860°C for 4 hours to obtain powder D.

[0170] The powder D was mixed with zircon and deionized water in a mass ratio of 1:5.2:1.2, and then ball-milled, dried and calcined at 850°C for 4 hours to obtain LiTaO3 powder.

[0171] The Na was weighed according to a molar ratio of 94:6. 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:5.2:1.2 and then ball-milled, dried and calcined at 860°C for 4 hours to obtain powder F.

[0172] The powder F was mixed with zircon and deionized water in a mass ratio of 1:5.2:1.2, and then ball-milled, dried, and calcined at 860°C for 4 hours to obtain Na. 0.465 Li 0.07 Bi0.465 Ta 0.07 Ti 0.93 O3 powder.

[0173] BaLa2Ti4O 12 The preparation of the powder is specifically as follows:

[0174] BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:4.5 to form mixture G. Mixture G, zircon and deionized water were mixed in a mass ratio of 1:5.2:1.2 and then ball-milled, dried and calcined at 1150℃ for 4 hours to obtain powder H.

[0175] The powder H was mixed with zircon and deionized water in a mass ratio of 1:5.2:1.2, and then ball-milled, dried, and calcined at 1150°C for 4 hours to obtain BaLa2Ti4O. 12 ;

[0176] Step 2: Mix the prepared ingredients with zircon and deionized water at a mass ratio of 1:5.2:1.2, then ball mill and dry the mixture. Grind the dried material through a 160-mesh sieve.

[0177] The ball milling time described in steps 1 and 2 above is 12 hours, followed by drying at 100℃ for 24 hours;

[0178] Step 3: The sieved material is first pressed at 200MPa for 4 minutes, then pressed at 200MPa for 6 minutes, and finally depressurized at 50MPa / min to form a green body by cold isostatic pressing; in a box furnace, the temperature is first raised to 1150℃ in 230 minutes and held for 2.5 hours, then cooled to 520℃ in 130 minutes and finally cooled to room temperature with the furnace to obtain a temperature-stable multiphase ceramic.

Claims

1. A temperature-stable multiphase ceramic material for high-temperature capacitors, characterized in that, The stoichiometric formula is: (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 , where 0.01≤x≤0.

05.

2. A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors, characterized in that, Includes the following steps: Step 1: According to the stoichiometric formula (1-x)Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3-xBaLa2Ti4O 12 0.01≤x≤0.05, weigh Na 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder and BaLa2Ti4O 12 Powders are mixed evenly to form the complete ingredients; Step 2: The complete batch of ingredients is ball-milled, dried, and sieved to form sieved material; Step 3: Press the sieved material into a green body, and sinter the green body to obtain a temperature-stable multiphase ceramic.

3. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, Na in step 1 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder is obtained through the following steps: Weigh Na2CO3, Bi2O3 and TiO2 according to a molar ratio of 1:1:(3.5-4.5) and mix them to form mixture A. Take mixture A, zircon and deionized water and mix them according to a mass ratio of 1:(4.8-5.2):(0.8-1.2). Then, ball mill, dry and calcine at 850-860℃ for 3-4 hours to obtain powder B. Powder B was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.5 Bi 0.5 TiO3 powder; Li2CO3 and Ta2O5 were weighed and mixed in a molar ratio of (0.8-1.2):(0.8-1.2) to form mixture C. Mixture C, zircon, and deionized water were then mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), followed by ball milling, drying, and calcination at 850-860℃ for 3-4 hours to obtain powder D. The powder D was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain LiTaO3 powder. Weigh the Na according to the molar ratio (92-94):(6-8). 0.5 Bi 0.5 TiO3 and the LiTaO3 powder are mixed to form mixture E. Mixture E, zircon and deionized water are mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried and calcined at 850-860℃ for 3-4 hours to obtain powder F. The powder F was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 850-860℃ for 3-4 hours to obtain Na. 0.465 Li 0.07 Bi 0.465 Ta 0.07 Ti 0.93 O3 powder.

4. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, In step 1, BaLa2Ti4O 12 The powder is obtained through the following steps: BaCO3, La2O3 and TiO2 were weighed and mixed in a molar ratio of 1:1:(3.5-4.5) to form a mixture G. The mixture G, zircon and deionized water were mixed in a mass ratio of 1:(4.8-5.2):(0.8-1.2) and then ball-milled, dried and calcined at 1050-1150℃ for 3-4 hours to obtain powder H. The powder H was mixed with zircon and deionized water in a mass ratio of 1:(4.8-5.2):(0.8-1.2), and then ball-milled, dried, and calcined at 1050-1150℃ for 3-4 hours to obtain BaLa2Ti4O. 12 .

5. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, In step 2, the whole batch of ingredients is mixed with zircon and deionized water at a mass ratio of 1:(4.8-5.2):(0.8-1.2), then ball-milled and dried.

6. A method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 3, 4, or 5, characterized in that, The ball milling process lasts 12-24 hours, followed by drying at 85-100℃ for 24 hours.

7. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, The sieve used in step 2 has a mesh size of 140-160.

8. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, The pressing process in step 3 specifically involves holding the pressure at 180-220 MPa for 2-4 minutes, then holding the pressure at 170-200 MPa for 4-6 minutes, and finally releasing the pressure at 30-50 MPa / min to form a blank through cold isostatic pressing.

9. The method for preparing a temperature-stable multiphase ceramic material for high-temperature capacitors according to claim 2, characterized in that, The sintering in step 3 specifically involves first heating the furnace to 1100-1150°C in 210-230 minutes, holding the temperature for 1.5-2.5 hours, then cooling the furnace to 480-520°C in 110-130 minutes, and finally cooling the furnace to room temperature.

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