Orthogonal-tetragonal multilayer heterostructure anti-ferroelectric ceramic and preparation method thereof

Abstract

The invention provides orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic and a preparation method thereof. Tetragonal phase antiferroelectric presintering powder is prepared, orthogonal phase antiferroelectric presintering powder is prepared, the tetragonal phase antiferroelectric presintering powder and the orthogonal phase antiferroelectric presintering powder are respectively subjected to secondary ball milling, drying and sieving and then subjected to tape casting treatment, and the antiferroelectric ceramic with the orthogonal-tetragonal multilayer heterostructure is obtained. A single-layer film A and a single-layer film B are obtained; and carrying out heterogeneous lamination temperature isostatic pressing treatment on the single-layer film A and the single-layer film B according to modes of AAAA, ABBA, BAAB, ABAB and BBBB to obtain the multi-layer heterostructure anti-ferroelectric ceramic, carrying out glue removal on the multi-layer heterostructure anti-ferroelectric ceramic, and calcining to obtain the orthogonal-tetragonal multi-layer heterostructure anti-ferroelectric ceramic. According to the multilayer heterostructure constructed by the invention, the breakdown field strength and the macroscopic polarization response of the material are synergistically improved through the interface blocking effect induced by the interlayer interface and the MWS interface polarization effect, so that the energy storage density is effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of electronic information materials and components technology, specifically relating to an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic and its preparation method. Background Technology

[0002] Ceramic capacitors have important applications in the electrical and electronic fields. They are generally used as energy and signal processing components. For example, in inverters, they can be used as DC support capacitors to buffer energy and maintain the stability of the bus voltage. They can also be used as energy storage components in pulsed power systems to store electrical energy at a relatively slow speed and then release it instantaneously to form a pulsed large current, ultimately enabling subsequent applications such as lasers, X-rays, and propulsion.

[0003] The key to ceramic capacitors lies in the dielectric material. When used for energy processing, capacitors should possess high energy density and efficiency. High energy density facilitates the miniaturization of electrical and electronic systems, while efficiency represents the energy conversion efficiency; higher capacitor energy efficiency is more conducive to the effective utilization of energy. Antiferroelectric materials, due to their unique phase transition behavior, are an ideal dielectric material for capacitors.

[0004] Currently used antiferroelectric materials can be broadly classified into orthorhombic and tetragonal phases based on their crystal structure, and their hysteresis loops are as follows: Figure 1 As shown (the hysteresis loop, or PE curve, is a curve plotted with electric field on the x-axis and polarization intensity on the y-axis, reflecting the polarization and energy storage characteristics of the dielectric material). Orthorhombic phases generally have a "square" hysteresis loop; this type of antiferroelectric material has high polarization intensity and can achieve high energy storage density (i.e.,...). Figure 1 The area enclosed by the right branch of the PE curve and the polarization intensity axis), but at the same time, the loss is relatively large (i.e. Figure 1 The area enclosed inside the PE curve in the middle phase has lower efficiency; while the tetragonal antiferroelectric has a "slender" hysteresis loop with lower polarization intensity, which is not conducive to obtaining high energy density, but has low loss and high efficiency.

[0005] Therefore, finding a technical means that can take into account the advantages of both types of antiferroelectricity and make up for various defects is one of the key points in the current development of ceramic capacitor dielectric materials. Summary of the Invention

[0006] The purpose of this invention is to provide an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic and its preparation method, overcoming the shortcomings of existing technologies. The multilayer heterostructure constructed in this invention synergistically enhances the breakdown field strength and macroscopic polarization response of the material through the interlayer interface-induced interface barrier effect and the MWS interface polarization effect, thereby effectively improving the energy storage density. Furthermore, this invention fundamentally solves the technical bottleneck of poor temperature stability in traditional antiferroelectric ceramics by combining a tetragonal phase with a positive and a trigonal phase, which have positive and negative temperature coefficients respectively, utilizing the complementary properties of their temperature-dependent performance changes.

[0007] This invention is achieved through the following technical solution: A method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic includes the following steps: Step 1: Preparation of tetragonal antiferroelectric pre-calcined powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder A. Mixed powder A is ball-milled and dried once to obtain dried powder A. Dried powder A is calcined at 800℃-880℃ for 2h~3h to obtain tetragonal antiferroelectric pre-calcined powder. Step 2, Preparation of orthogonal opposite ferroelectric pre-calcined powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder B. The mixed powder B is ball-milled and dried to obtain dried powder B. The dried powder B is calcined at 800℃-880℃ for 2h~3h to obtain orthogonal opposite ferroelectric pre-calcined powder. Step 3: Preparation of multilayer heterostructure antiferroelectric ceramics: Tetragonal antiferroelectric pre-calcined powder and orthogonal antiferroelectric pre-calcined powder are subjected to secondary ball milling, drying and sieving, and then cast film treatment to obtain monolayer film A and monolayer film B; monolayer film A and monolayer film B are subjected to heterostructure stacking temperature isostatic pressing treatment in the manner of AAAA, ABBA, BAAB, ABAB and BBBB to obtain multilayer heterostructure antiferroelectric ceramics; after debinding the multilayer heterostructure antiferroelectric ceramics, they are calcined at 1200 ℃~1250 ℃ for 2h~3h to obtain orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramics.

[0008] Further, in step 1, the molar ratio of Pb3O4, BaCO3, La2O3, ZrO2, SnO2 and TiO2 is 0.915:0.04:0.03:0.60:0.35:0.05.

[0009] Further, in step 2, the molar ratio of Pb3O4, Tm2O3, SrCO3, ZrO2, SnO2 and TiO2 is 0.9:0.04:0.04:0.695:0.35:0.005.

[0010] Furthermore, in steps 1 and 2, the rotation speed of the ball mill is 300~400 r / min, the time is 15h~48h, and the drying temperature is 50~90℃.

[0011] Furthermore, the particle size distribution of the dried powder A and the dried powder B conforms to a normal distribution, and satisfies that D50 is 0.1~1μm and D90 is 0.1~10μm.

[0012] Furthermore, in step 3, the rotation speed of the secondary ball mill is 300~400 r / min, and the time is 15~48 h; The drying temperature is 60℃~90℃; The sieve mesh size is 80~200 mesh.

[0013] Furthermore, the particle size distribution of the powder obtained after the tetragonal opposite ferroelectric pre-calcined powder and the orthogonal opposite ferroelectric pre-calcined powder are subjected to secondary ball milling, drying and sieving respectively conforms to a normal distribution and satisfies that D50 is 0.1~1μm and D90 is 0.1~10μm.

[0014] Furthermore, in step 3, the thickness of monolayer A and monolayer B is 10~30μm, and the temperature of the isostatic pressing treatment is 45℃~80℃, and the pressure is 1MPa~10MPa.

[0015] Furthermore, the temperature for discharging the adhesive in step 3 is 500℃~700℃, the heating rate is 0.2℃ / min, and the holding time is 2h~4h.

[0016] An orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic was prepared using the method described above.

[0017] Compared with the prior art, the present invention has the following beneficial technical effects: This invention addresses the intrinsic incompatibility between two types of antiferroelectric phases in terms of crystal symmetry, lattice constant matching, antipolarization domain evolution dynamics, and field-induced phase transition paths. It proposes a controllable heterostructure stacking strategy to enhance interfacial coupling, rather than simply a physical superposition of orthorhombic and tetragonal antiferroelectric materials. While orthorhombic antiferroelectrics possess high electric field-induced polarization intensity and energy density, their temperature coefficient is negative, and antipolarization domains are prone to irreversible degradation with increasing temperature. Tetragonal phase materials, on the other hand, have high energy conversion efficiency and a positive temperature coefficient, but their electro-induced phase transition driving force is limited, and the available effective polarization window is narrow, thus restricting their energy density. Using conventional solid solution or mixing methods, the significant differences between the two phases in polarization orientation, band structure, interfacial stress field, and antiferroelectric-ferroelectric phase transition energy barrier lead to interfacial barrier instability, domain structure disorder, and hysteresis loop broadening, making it difficult to simultaneously achieve high energy density and high temperature reliability. This invention constructs an orthogonal / tetragonal heterolayered structure with controlled interface polarization coupling, enabling the formation of a stable local electric field gradient and a built-in stress field control region in the interface area. This significantly improves the phase stability of the orthogonal phase at high temperatures and enhances the reversible polarization response of the tetragonal phase, allowing for synergistic control of the nucleation, expansion, and recovery processes of antipolarized domains. This heterolayer interface effect not only reduces the overall field-induced phase transition energy barrier and refines the hysteresis loop, but also generates a nonlinear synergistic enhancement mechanism that cannot be obtained in a single-phase system. This results in a significant "1+1>2" effect in energy storage density and efficiency, breaking the inherent limitations between energy storage performance and temperature stability in traditional antiferroelectric energy storage ceramics and achieving a breakthrough improvement in comprehensive dielectric energy storage characteristics.

[0018] The advantages of the multilayer heterostructure antiferroelectric ceramic prepared by this invention lie in the synergistic enhancement of the material's breakdown field strength and macroscopic polarization response through the interlayer-induced interface barrier effect and the MWS interface polarization effect, thereby effectively improving the energy storage density. The obtained ABBA heterostructure stack has an energy storage density and energy storage efficiency of 9.80 J / cm³. 3 And 87.7%. Furthermore, it achieved an energy storage efficiency of 95.4% (160℃) and a minimum energy storage density of 4.1 J / cm³ over a wide temperature range (20℃~160℃). 3 This is an energy storage material. It has significant value for the practical application of antiferroelectric energy storage ceramic materials. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. The following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0020] Figure 1The PE curves are for heterogeneous stacked structures, tetragonal phases, and orthogonal opposite ferroelectrics in Example 1.

[0021] Figure 2 The figures show the room temperature PE and temperature-varying PE of different heterostructured multilayer ceramics prepared in Example 1, where (a) represents the PE of ceramics A1 to A5. P - E Figure (b) shows the temperature variation. P - E picture. Detailed Implementation

[0022] The present invention will now be described in detail: A method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic includes the following steps: (1) Preparation of tetragonal antiferroelectric pre-calcined powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder A, wherein the molar ratio of Pb3O4, BaCO3, La2O3, ZrO2, SnO2 and TiO2 is 0.915:0.04:0.03:0.60:0.35:0.05; After the mixed powder A is ball-milled once (the ball milling speed is 300~400 r / min, the time is 15h~48h) and dried (the temperature is 50~90℃), the dried powder A is obtained. The particle size distribution of the dried powder A conforms to the normal distribution and satisfies that D50 is 0.1~1μm and D90 is 0.1~10μm. The dried powder A is kept at 800℃-880℃ for 2h~3h to obtain tetragonal antiferroelectric pre-calcined powder. (2) Preparation of orthogonal opposite ferroelectric pre-calcined powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder B, wherein the molar ratio of Pb3O4, Tm2O3, SrCO3, ZrO2, SnO2 and TiO2 is 0.9:0.04:0.04:0.695:0.35:0.005; After the mixed powder B is ball-milled once (the ball milling speed is 300~400 r / min and the time is 15h~48h) and dried (the temperature is 50~90℃), the dried powder B is obtained. The particle size distribution of the dried powder B conforms to the normal distribution and satisfies that D50 is 0.1~1μm and D90 is 0.1~10μm. The dried powder B is kept at 800℃-880℃ for 2h~3h to obtain the orthogonal opposite ferroelectric pre-calcined powder. (3) Preparation of multi-layer heterostructure antiferroelectric ceramics: The tetragonal antiferroelectric pre-sintered powder and the orthorhombic antiferroelectric pre-sintered powder are respectively subjected to secondary ball milling (the rotation speed of the ball milling is 300 - 400 r / min, and the time is 15h - 48h), drying (the temperature is 60 - 90 °C), and sieving to control the particle size distribution of the powder to conform to a normal distribution, and satisfy D50 of 0.1 - 1μm and D90 of 0.1 - 10μm. Then, tape casting treatments are respectively carried out to obtain monolayer film A and monolayer film B; Monolayer film A and monolayer film B are subjected to isostatic pressing treatment of heterogeneous lamination in the manner of "AAAA", "ABBA", "BAAB", "ABAB", and "BBBB". The obtained multi-layer heterostructure antiferroelectric ceramics are first debinded and then calcined at a temperature of 1200 °C - 1250 °C for 2h - 3h to obtain orthorhombic-tetragonal multi-layer heterostructure antiferroelectric ceramics.

[0023] Among them, in the process of tape casting treatment, the formula is: the powders obtained by respectively subjecting the tetragonal antiferroelectric pre-sintered powder and the orthorhombic antiferroelectric pre-sintered powder to secondary ball milling, drying, and sieving, a dispersant, a plasticizer, a solvent, and a PVB colloid. The mass ratio between the powder, the dispersant, the plasticizer, the solvent, and the PVB colloid is 50:1:36:4; The solvent is a mixed solvent of xylene and ethanol, and the mass ratio between xylene and ethanol is 1:3.

[0024] The thickness of monolayer film A and monolayer film B is 13 - 27μm, the temperature of isostatic pressing is 45 °C - 80 °C, the pressure is 1MPa - 10Mpa, the heating rate during debinding is 0.2 °C / min, and it is kept warm at 500 - 700 °C for 2 - 4 hours.

[0025] According to another aspect of the present invention, there is provided an orthorhombic-tetragonal multi-layer heterostructure antiferroelectric ceramic, and the orthorhombic-tetragonal multi-layer heterostructure antiferroelectric ceramic is a heterogeneous lamination of an orthorhombic antiferroelectric dielectric (i.e., monolayer film B) and a tetragonal antiferroelectric dielectric (i.e., monolayer film A); The tetragonal antiferroelectric dielectric is (Pb 0.955-x La 0.03 Ba x )(Zr 0.6 Sn 0.35 Ti 0.05 )O3, where the value range of x is 0.01 ≤ x ≤ 0.04, preferably, x = 0.035, and the orthorhombic antiferroelectric dielectric is (Pb 0.94-y Tm 0.04 Sr y )(Zr 0.695 Sn 0.35 Ti 0.005 )O3, where the value range of y is 0.01 < y < 0.05, preferably, y = 0.04.

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise specified, the methods and experimental equipment used in the following embodiments are conventional methods and instruments.

[0027] Example 1 (1) Preparation of tetragonal antiferroelectric pre-calcined powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.915:0.04:0.03:0.60:0.35:0.05. Wet ball milling was used, and the powder was placed in a ball mill jar and ball milled for 15 h according to the mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The speed of the planetary ball mill was 300 rpm / min, and the drying temperature was 50℃ to obtain dried powder A. The particle size distribution of dried powder A conforms to the normal distribution and satisfies D50 of 0.1 μm and D90 of 0.1 μm. The dried powder A was placed in a box furnace and heated to 800℃ at a heating rate of 5℃ / min. Heating and sintering at ℃, and holding in air for 2 hours, yields tetragonal antiferroelectric pre-sintered powder.

[0028] (2) Preparation of orthogonal opposite ferroelectric pre-sintered powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.90:0.04:0.04:0.695:0.35:0.005. They were placed in a ball milling jar and ball milled for 15 h according to the mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The speed of the planetary ball mill was 320 rpm / min and the drying temperature was 50℃ to obtain dried powder B. The particle size distribution of dried powder B conforms to the normal distribution and satisfies D50 of 0.1 μm and D90 of 0.1 μm. The dried powder B was placed in a box furnace and heated and sintered at 800 ℃ and kept in air for 2 h.

[0029] (3) The tetragonal antiferroelectric pre-calcined powder was subjected to secondary ball milling (300 rpm / min, 12 h), drying (50 °C), and sieving to control the particle size distribution of the powder to conform to a normal distribution, with D50 and D90 of 0.1 μm. Then, a slurry with good flowability was obtained by mixing powder, plasticizer, solvent, and PVB in a mass ratio of 50:1:36:2, where the solvent was a mixture of xylene and ethanol in a mass ratio of 1:3. The slurry was processed by a casting machine to obtain a single-layer film A with a thickness of 13 μm.

[0030] The orthogonal reverse ferroelectric pre-calcined powder was subjected to secondary ball milling (300 rpm / min, 12 h), drying (50 °C), and sieving to control the particle size distribution to conform to a normal distribution with a D90 of 4 μm. Then, a slurry with good flowability was obtained by mixing powder, plasticizer, solvent, and PVB in a mass ratio of 50:1:36:5. The solvent was a mixture of xylene and ethanol in a mass ratio of 1:3. This slurry was processed using a casting machine to obtain a single-layer film B with a thickness of 27 μm.

[0031] Single-layer films A and B were subjected to heterogeneous stacking isostatic pressing (WHP) treatment in the following patterns: “AAAA” (A1), “ABBA” (A2), “BAAB” (A3), “ABAB” (A4), and “BBBB” (A5). The temperature was 45°C and the pressure was 6 MPa. The pressed ceramics were then placed in a box furnace for debinding, with a heating rate of 0.2°C / min, and held at 500°C for 2 hours. Then, the temperature was increased to 1200°C for sintering, and held in air for 2 hours to obtain high-performance multilayer heterostructure antiferroelectric ceramics.

[0032] Figure 2(a) shows the hysteresis loops of the A1-A5 multilayer ceramics at room temperature under the maximum applied electric field, with a test frequency of 10 Hz. It can be observed that the hysteresis loop of the A1 ceramic exhibits a "thin" double hysteresis loop, displaying typical tetragonal antiferroelectric properties. The A5 ceramic shows a multi-stage phase transition hysteresis loop, exhibiting typical orthogonal antiferroelectric properties. It can be seen that the phase transition electric fields of the A2, A3, and A4 multilayer ceramics are closer to those of the A5 ceramic, which has a higher phase transition electric field. Furthermore, the A2, A3, and A4 multilayer ceramics also exhibit lower hysteresis widths. Notably, the saturation polarization of the A2, A3, and A4 multilayer ceramics is consistently higher than that of the A1 and A5 ceramics. This enhanced saturation polarization is due, on the one hand, to the Maxwell-Wagner interfacial polarization established at the single A1 and A5 heterojunction under the applied electric field. On the other hand, the significant difference in the dielectric constant εr between the two materials generates space charge at the heterojunction, leading to an enhanced dipole moment of the overall polarization. When the electric field strength Eb is 430 kV / cm, the A3 ceramic achieves an effective energy storage density Wrec of 9.8 J / cm³ and an energy storage efficiency η of 87.7%. The energy storage performance at various temperature points is calculated as follows: Figure 2 As shown in Figure (b), the results show that Wrec gradually decreased from 6.89 J / cm3 at room temperature to 4.1 J / cm3 at 160℃, while the energy storage efficiency η remained above 85.4% throughout the temperature range, demonstrating excellent temperature stability.

[0033] Example 2 (1) Preparation of tetragonal antiferroelectric pre-sintered powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.915:0.04:0.03:0.60:0.35:0.05. They were placed in a ball milling jar and ball milled for 24 hours according to a mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The planetary ball mill was rotated at 320 rpm / min and the drying temperature was 70℃ to obtain dried powder A. The particle size distribution of dried powder A conforms to the normal distribution and satisfies D50 of 0.5μm and D90 of 4μm. The dried powder A was placed in a box furnace and heated to sinter at 850℃ and kept in air for 2.5 hours to obtain tetragonal antiferroelectric pre-sintered powder.

[0034] (2) Preparation of orthogonal opposite ferroelectric pre-sintered powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.90:0.04:0.04:0.695:0.35:0.005. They were placed in a ball milling jar and ball milled for 24 hours according to a mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The rotation speed of the planetary ball mill was 350 rpm / min and the drying temperature was 70℃ to obtain dried powder B. The particle size distribution of dried powder B conforms to the normal distribution and satisfies D50 of 0.5μm and D90 of 2μm. The dried powder B was placed in a box furnace and heated to sinter at 850℃ and kept in air for 2.5 hours to obtain orthogonal opposite ferroelectric pre-sintered powder.

[0035] (3) The tetragonal antiferroelectric pre-calcined powder was subjected to secondary ball milling (350 rpm / min, 24 h), drying (70 °C), and sieving to control the particle size distribution of powder A to conform to a normal distribution, with D50 and D90 of 2 μm. Then, a slurry with good flowability was obtained by mixing powder, plasticizer, solvent, and PVB in a mass ratio of 50:1:36:2. The solvent was a mixture of xylene and ethanol in a mass ratio of 1:3. The resulting monolayer film A was 15 μm thick after being processed by a casting machine.

[0036] The orthogonal reverse ferroelectric pre-calcined powder was subjected to secondary ball milling (350 rpm / min, 24 h), drying (70 °C), and sieving to control the particle size distribution to conform to a normal distribution with a D90 of 4 μm. Then, a slurry with good flowability was obtained by mixing powder, plasticizer, solvent, and PVB in a mass ratio of 50:1:36:4. The solvent was a mixture of xylene and ethanol in a mass ratio of 1:3. This slurry was processed using a casting machine to obtain a single-layer film B with a thickness of 25 μm.

[0037] Single-layer films A and B were subjected to heterogeneous stacking and isostatic pressing (WHP) treatment according to the patterns “AAAA” (A1), “ABBA” (A2), “BAAB” (A3), “ABAB” (A4), and “BBBB” (A5) at a temperature of 55°C and a pressure of 6 MPa. The pressed ceramics were then placed in a box furnace for debinding, with a heating rate of 0.2°C / min, and held at 600°C for 3 hours. Then, the temperature was increased to 1220°C for sintering, and held in air for 2.5 hours to obtain high-performance multilayer heterostructure antiferroelectric ceramics.

[0038] Example 3 (1) Preparation of tetragonal antiferroelectric pre-sintered powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.915:0.04:0.03:0.60:0.35:0.05. They were placed in a ball milling jar and ball milled for 48h according to a mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The rotation speed of the planetary ball mill was 400rpm / min and the drying temperature was 90℃ to obtain dried powder A. The particle size distribution of dried powder A conforms to the normal distribution and satisfies D50 of 1μm and D90 of 10μm. The dried powder A was placed in a box furnace and heated and sintered at 880℃ and kept in air for 3h to obtain tetragonal antiferroelectric pre-sintered powder.

[0039] (2) Preparation of orthogonal opposite ferroelectric pre-sintered powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder were weighed according to a molar ratio of 0.90:0.04:0.04:0.695:0.35:0.005. They were placed in a ball milling jar and ball milled for 36 hours according to a mass ratio of powder:milling media (zirconia balls):ethanol = 1:1.25:1.2. The planetary ball mill speed was 400 rpm / min and the drying temperature was 90℃ to obtain dried powder B. The particle size distribution of dried powder B conforms to the normal distribution and satisfies D50 of 1μm and D90 of 10μm. The dried powder B was placed in a box furnace and heated to sinter at 880℃ and kept in air for 3 hours to obtain orthogonal opposite ferroelectric pre-sintered powder.

[0040] (3) The tetragonal antiferroelectric pre-calcined powder was subjected to secondary ball milling (400 rpm / min, 48 h), drying (90 °C), and sieving to control the particle size distribution of the powder to conform to a normal distribution, with D50 of 1 μm and D90 of 10 μm. Then, a slurry with good flowability was obtained according to the mass ratio of powder:plasticizer:solvent:PVB = 50:1:36:4. The solvent was a mixture of xylene and ethanol mixed at a mass ratio of 1:3, which was processed by a casting machine to obtain a single-layer film A with a thickness of 15 μm.

[0041] The orthogonal reverse ferroelectric pre-calcined powder was subjected to secondary ball milling (400 rpm / min, 48 h), drying (90 °C), and sieving to control the particle size distribution to conform to a normal distribution with a D90 of 10 μm. Then, a slurry with good flowability was obtained by mixing powder, plasticizer, solvent, and PVB in a mass ratio of 50:1:36:7. The solvent, a mixture of xylene and ethanol in a mass ratio of 1:3, was processed using a casting machine to obtain a single-layer film B with a thickness of 23 μm.

[0042] Single-layer films A and B were subjected to heterogeneous stacking and isostatic pressing (WHP) treatment in the following patterns: “AAAA” (A1), “ABBA” (A2), “BAAB” (A3), “ABAB” (A4), and “BBBB” (A5). The temperature was 80℃ and the pressure was 6MPa. The pressed ceramics were then placed in a box furnace for debinding, with a heating rate of 0.2℃ / min, and held at 700℃ for 4 hours. Then, the temperature was increased to 1250℃ for sintering and held in air for 3 hours, resulting in a high-performance multilayer heterostructure antiferroelectric ceramic.

[0043] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic, characterized in that, Includes the following steps: Step 1: Preparation of tetragonal antiferroelectric pre-calcined powder: Pb3O4 powder, BaCO3 powder, La2O3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder A. Mixed powder A is ball-milled and dried once to obtain dried powder A. Dried powder A is calcined at 800℃-880℃ for 2h~3h to obtain tetragonal antiferroelectric pre-calcined powder. Step 2, Preparation of orthogonal opposite ferroelectric pre-calcined powder: Pb3O4 powder, Tm2O3 powder, SrCO3 powder, ZrO2 powder, SnO2 powder and TiO2 powder are thoroughly mixed to obtain mixed powder B. The mixed powder B is ball-milled and dried to obtain dried powder B. The dried powder B is calcined at 800℃-880℃ for 2h~3h to obtain orthogonal opposite ferroelectric pre-calcined powder. Step 3: Preparation of multilayer heterostructure antiferroelectric ceramics: Tetragonal antiferroelectric pre-calcined powder and orthogonal antiferroelectric pre-calcined powder are subjected to secondary ball milling, drying and sieving, and then cast film treatment to obtain monolayer film A and monolayer film B; monolayer film A and monolayer film B are subjected to heterostructure stacking temperature isostatic pressing treatment in the manner of AAAA, ABBA, BAAB, ABAB and BBBB to obtain multilayer heterostructure antiferroelectric ceramics; after debinding the multilayer heterostructure antiferroelectric ceramics, they are calcined at 1200 ℃~1250 ℃ for 2h~3h to obtain orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramics.

2. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, In step 1, the molar ratio of Pb3O4, BaCO3, La2O3, ZrO2, SnO2 and TiO2 is 0.915:0.04:0.03:0.60:0.35:0.

05.

3. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, In step 2, the molar ratio of Pb3O4, Tm2O3, SrCO3, ZrO2, SnO2 and TiO2 is 0.9:0.04:0.04:0.695:0.35:0.

005.

4. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, In steps 1 and 2, the rotation speed of the ball mill is 300~400 r / min, the time is 15h~48h, and the drying temperature is 50~90℃.

5. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, The particle size distribution of the dried powder A and dried powder B conforms to a normal distribution, and satisfies that D50 is 0.1~1μm and D90 is 0.1~10μm.

6. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, In step 3, the rotation speed of the secondary ball mill is 300~400 r / min, and the time is 15~48 h; The drying temperature is 60℃~90℃; The sieve mesh size is 80~200 mesh.

7. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, The particle size distribution of the pre-calcined tetragonal opposite ferroelectric powder and the pre-calcined orthogonal opposite ferroelectric powder after secondary ball milling, drying and sieving conforms to a normal distribution and satisfies D50 of 0.1~1μm and D90 of 0.1~10μm.

8. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, In step 3, the thickness of monolayer A and monolayer B is 10~30μm, and the temperature of the isostatic pressing treatment is 45℃~80℃, and the pressure is 1MPa~10MPa.

9. The method for preparing an orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic according to claim 1, characterized in that, The temperature for discharging the adhesive in step 3 is 500℃~700℃, the heating rate is 0.2℃ / min, and the holding time is 2h~4h.

10. An orthogonal-tetragonal multilayer heterostructure antiferroelectric ceramic, characterized in that, It is prepared by the preparation method according to any one of claims 1-9.

Images