46 results about "Lead titanate" patented technology

The invention provides a lead zirconate titanate composite film with a high electro-optical coefficient, a preparation method of the lead zirconate titanate composite film and an electro-optical modulator, the lead zirconate titanate composite film comprises an insulating substrate, a buffer layer and a ferroelectric main body layer which are sequentially stacked, and the buffer layer is a lanthanum-doped lead zirconate titanate film; the ferroelectric main body layer is a lead zirconate titanate thin film and has (001) / (100) orientation. The composite film has a relatively high electro-optical coefficient, relatively low driving voltage and relatively high thermal stability.

The invention relates to the technical field of piezoelectric ceramics, in particular to a bismuth ferrite-lead titanate-zinc bismuth titanate ternary system piezoelectric ceramic material as well as preparation and application thereof. The chemical general formula of the bismuth ferrite-lead titanate-zinc bismuth titanate ternary system piezoelectric ceramic material disclosed by the invention is (1-x-y) BiFeO3-x (PbMez) TiO3-yBi (Zn0. 5Ti0. 5) O3, wherein Me is an alkaline earth metal element, x is equal to 0.4-0.8, y is equal to 0.05-0.3, z is equal to 0.05-0.5, and 1-x-y is greater than 0. The piezoelectric ceramic material has large anisotropy (d33 / d31 is between 5 and 60) and relatively high voltage (d33 is greater than 100pC / N), has a wide application prospect in the technical field of high-frequency image sonar transducers, and solves the problems of low piezoelectric coefficient and piezoelectric anisotropy of the existing bismuth ferrite-lead titanate-zinc bismuth titanate ternary system piezoelectric ceramic material.

This application relates to the field of electrochemical technology, specifically to polyester composite films and their preparation methods, composite current collectors and their preparation methods, electrodes and their applications. The polyester composite film of this application comprises: a polyester substrate layer and a first surface layer and a second surface layer respectively disposed on opposite sides of the polyester substrate layer; the polyester substrate layer comprises, by weight, 90 to 99 parts of polyester material and 1 to 10 parts of photo-straining material; the first and second surface layers comprise polyethylene terephthalate polymers; the transmittance of the first surface layer, the second surface layer, and the polyester material is independently 92% to 99%; the photo-straining material comprises one or more of barium titanate ceramics, lead zirconate titanate ceramics, PI / CNTs photosensitive composite materials, PEEK / anthraquinone photosensitive composite materials, MIL-101 chromium metal-organic frameworks, and UiO-66-NH2 / ZnO composite materials. The polyester composite film can easily break under high-destructive external forces such as battery breakdown and battery collision, effectively suppressing thermal runaway.

This invention discloses a phase-field method for multi-topological domain cyclic transformation in lead titanate (PTO) ferroelectric thin films. A computational model of the PTO ferroelectric thin film is established, defining polarization, potential, displacement, and oxygen vacancy concentration as field variables. Based on Ginzburg-Landau theory, a total free energy expression for the PTO ferroelectric thin film is established, incorporating oxygen vacancy transport processes and the coupling between oxygen vacancies and the electrostatic field. Combining time-correlated Ginzburg-Landau kinetic equations, mechanical equilibrium equations, electrostatic equilibrium equations, and Nernst-Planck equations, a phase-field model of the PTO ferroelectric thin film coupled with multiple physics fields is established. A stable initial skyrmion domain structure is constructed, and a preset uniform electric field sequence is applied to simulate the cyclic transformation process between skyrmions and flux-closed domains and / or stripe domains. This method can analyze the evolution path, transformation threshold, oxygen vacancy distribution, and cyclic stability of topological domains in PTO ferroelectric thin films under the synergistic effect of an applied electric field and oxygen vacancies, providing a theoretical basis for the design of ferroelectric topological domain multi-state storage devices.

The invention discloses a heat treatment method of high-polarization-intensity bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic, which comprises the following steps: arranging an electrode on the surface of a bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic sintered body, and then putting the sintered body into a rapid annealing furnace; the preparation method comprises the following steps: heating to 550-650 DEG C from room temperature at a heating rate of 5-80 DEG C / s, carrying out heat preservation for 45-75 seconds, carrying out first rapid annealing, and cooling to room temperature at a cooling rate of 250-350 DEG C / s, thereby obtaining the bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic. The heat treatment method provided by the invention can rearrange defects in the ceramic, increase domain conversion switches, improve the performance of the ceramic, and improve the performance of the ceramic. Furthermore, the ferroelectric piezoelectric property of the polarized BF-PT-BZT ceramic is greatly improved, and meanwhile, the polarized BF-PT-BZT ceramic has high Curie temperature.

The invention discloses an acousto-optic modulator based on heterogeneous integration of PZT and chalcogenide glass, and belongs to the technical field of integrated photoelectronics. The modulator sequentially comprises a silicon substrate, a silicon dioxide lower cladding layer and a lead zirconate titanate (PZT) piezoelectric film layer from bottom to top, a chalcogenide glass optical waveguide is heterogeneously integrated on the PZT layer, and the optical waveguide is patterned into a Mach-Zehnder interferometer (MZI) structure. An interdigital transducer (IDT) made of aluminum (Al) is arranged between two arms of the MZI, and air grooves which extend to a lower cladding layer or a substrate are etched in the outer sides of the two arms respectively. The advantage of high piezoelectric coefficient of PZT and the advantage of high photoelasticity of chalcogenide glass are combined through heterogeneous integration. Aluminum is used as an IDT electrode material, so that the mass loading effect of the electrode on the surface acoustic wave is effectively reduced; acoustic resonant cavities are constructed through air grooves in the outer sides of the two arms, sound wave energy is limited in an optical waveguide area, and the acousto-optic interaction is remarkably enhanced. The structure realizes optical signal modulation with low driving voltage, low loss and high efficiency, and is suitable for an integrated optical path system of intermediate infrared and communication wavebands.

The invention belongs to the technical field of special ceramic preparation, and particularly relates to lead zirconate titanate porous piezoelectric ceramic as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing an alkenyl-containing organic monomer, a cross-linking agent, an alcohol organic solvent, lead zirconate titanate powder and a dispersing agent, grinding, removing bubbles from the obtained premix, mixing with an initiator and an amine catalyst, and carrying out a polymerization reaction to obtain a gel blank; and sequentially drying and sintering the gel blank to obtain the lead zirconate titanate porous piezoelectric ceramic. The porosity of the lead zirconate titanate porous piezoelectric ceramic ranges from 45.40% to 64.87%, the piezoelectric voltage coefficient ranges from 43.95 * 10 <-3 > to 81.71 * 10 <-3 > Vm / N, the energy collection quality factor ranges from 9.95 * 10 <-12 > to 20.28 * 10 <-12 > m < 2 > / N, and the lead zirconate titanate porous piezoelectric ceramic has good application in high-sensitivity output and excellent energy collection materials.

The application relates to the technical field of piezoelectric materials, in particular to a lead zirconate titanate film and a low-temperature preparation method and application thereof, the preparation method comprising the following steps: Ti metal is taken as a radio frequency target material to perform first sputter deposition treatment on a substrate to form a Ti adhesion layer; a bottom electrode is formed on the Ti adhesion layer; Pb x Zr 0.52 Ti 0.48 O3 ceramic is taken as a radio frequency target material to perform second sputter deposition treatment on the bottom electrode, rapid heat treatment is performed, a PZT seed layer is formed; Pb x Zr 0.52 Ti 0.48 O3 ceramic is taken as a radio frequency target material to perform third sputter deposition treatment on the PZT seed layer, rapid heat treatment is performed, the step is repeated, and a lead zirconate titanate film is formed. In the process of sputter deposition of the PZT film material, the substrate tray is not additionally heated, the loss and volatilization of PbO are reduced, the film component stability can be effectively maintained; more crystal nuclei are provided by the PZT seed layer, the uniform crystallization of the PZT film is promoted, the crystallization quality and electrical properties of the PZT film are improved, the crystal boundary defects are reduced, and the adhesion and stability of the film and the substrate are enhanced.

The invention discloses a high-sensitivity mass-block-free piezoelectric acceleration sensor design which is suitable for weak vibration signal detection in the fields of industrial equipment monitoring, aerospace, consumer electronics and the like. Aiming at the problems of high cost, large size and limited bandwidth caused by mass block design and mechanical rigidity adjustment of a traditional piezoelectric acceleration sensor, a single lead zirconate titanate piezoelectric ceramic (PZT) sheet is adopted as a sensitive element, and collaborative improvement of sensitivity and bandwidth is realized through innovative structural design. The core structure of the sensor comprises an early warning bolt, a gasket, an upper insulating sheet, a lower insulating sheet, a piezoelectric sensitive element and a base. The early warning bolt exerts high pre-tightening force through a shell threaded hole, provides rigid contact downward pressure and ensures the rigidity of the whole structure. The gasket and the upper and lower insulating sheets form complete equal-surface contact, the contact area of the piezoelectric ceramic is maximized, and a traditional mass block is replaced; the insulation sheet is provided with a welding groove and a wiring groove, flatness deviation caused by welding spots is avoided, and charge transmission stability is guaranteed. According to the design, a mass block is omitted, the structure is simplified, the preparation cost is reduced, and meanwhile the size miniaturization of the sensor is achieved through the synergistic effect of high pre-tightening force and a low-rigidity structure. Tests show that the sensitivity of the sensor reaches 192.3 pC / g, the use frequency range covers 10-3000Hz (recommended 10-700Hz), and the sensor has the characteristics of high sensitivity and wide bandwidth, and is suitable for the high-end fields of ultra-precision measurement, extreme environment monitoring and the like.

The application provides a zirconium titanate lead film-based on-chip non-Hermitian extraordinary plane sensing structure and a preparation method thereof, and belongs to the technical field of integrated optical sensing. The sensing structure comprises a micro-ring resonant cavity formed by etching a zirconium titanate lead film wafer and composed of a ridge waveguide, a coupling waveguide located at the upper part of the micro-ring resonant cavity, and a Bragg grating at the right end of the coupling waveguide. An upper metal electrode and a lower metal electrode subjected to electrical polarization treatment are respectively deposited on the upper and lower sides of the right end of the coupling waveguide. The right end of the coupling waveguide, the upper metal electrode, the lower metal electrode and the Bragg grating form a non-Hermitian optical sensing reflection loop, and the coupling waveguide and the micro-ring resonant cavity couple light into the micro-ring resonant cavity through an evanescent wave coupling mode. The zirconium titanate lead film-based on-chip non-Hermitian extraordinary plane sensing structure provided by the application has high integration and stable non-Hermitian extraordinary plane regulation and control capability.

The application provides an energy collection structure based on a piezoelectric effect, and relates to the technical field of energy recycling, which comprises a circular supporting base, the top of the circular supporting base is fixed with a lower supporting plate, one side of the circular supporting base is provided with two first clamping mechanisms, and the top of the two first clamping mechanisms is provided with two second clamping mechanisms. Through cooperation of the beryllium bronze substrate, the lead zirconate titanate piezoelectric plate, the rectangular piezoelectric unit, the first circular magnet and the second circular magnet, the piezoelectric energy collection mechanism can realize multi-point collection, the situation that the whole system is paralyzed when a single energy collection module fails is effectively avoided, and the use efficiency is improved. The three beryllium bronze substrates are stably fixed through cooperation of the lower supporting plate, the upper supporting plate, the bolt, the first clamping mechanism and the second clamping mechanism. The vertical rod, the supporting rod, the connecting strip, the connecting rod and the screw are arranged, so that the spacing between the first clamping mechanism and the second clamping mechanism is conveniently adjusted.

The invention belongs to the technical field of piezoelectric ceramics, and particularly relates to a high-temperature magnesium bismuth titanate-lead zirconate titanate piezoelectric ceramic material and a preparation method thereof. Comprising the following chemical general formula: 0.65 Bi (Mg < 0.51 > Ti < 0.49 >) O < 3 >-0.35 Pb (Zr < x > Ti < 1-x >) O < 3-y > wt% La2O3, wherein x is equal to 0.01 to 0.7, and y is equal to 0.01 to 2. The piezoelectric ceramic material is prepared from the following raw materials: Pb3O4, TiO2, ZrO2, Nb2O5, Bi2O3, MgO and La2O3. The novel piezoelectric ceramic system has higher Curie temperature of 460-520 DEG C, and can work in a high-temperature environment of 260-400 DEG C. The novel piezoelectric ceramic system is suitable for being applied to a high-temperature sensor piezoelectric device.

The invention relates to the technical field of ferroelectric materials, in particular to a ferroelectric functional film and a preparation method thereof. The method comprises the following steps: depositing a target material on a substrate by adopting a pulse laser method, and carrying out post-treatment after deposition to obtain a ferroelectric functional film; the target material comprises one or two of a lead titanate target material and a strontium titanate target material. By changing technological parameters in the pulse laser deposition process, accurate control over the domain structure of the ferroelectric film is achieved, and the high-density and small-size domain structure is formed. The high-density domain structure obviously improves the physical properties such as piezoelectricity, dielectricity and the like of the ferroelectric film, and provides a material basis for high-performance electronic devices. The ferroelectric film prepared by the technology has potential application value in the field of high-density information memories, and is expected to solve the problem of density limitation in the existing storage technology.

The present invention provides a current collector plate with partitioned piezoelectric ceramics. The surface of the current collector plate is divided into several zones. The lead zirconate titanate (PZT) piezoelectric ceramics are prepared by high-temperature sintering, and the oxidation-resistant layer, which also serves as the piezoelectric ceramic's upper electrode, is formed by nickel plating. The present invention also provides a method for detecting the uniformity of force applied to a battery stack package. The method comprises a current collector plate with partitioned piezoelectric ceramics. The upper and lower electrodes of the piezoelectric ceramics are combined with a multi-channel oscilloscope and a computer to form a detection circuit. By calculating the cumulative voltage of each zone during assembly and comparing the force uniformity of different zones, this method can quantify and online detect the force applied to the edges of different zones during battery stack packaging. The current collector plate of the present invention is easy to manufacture, and the PZT piezoelectric ceramics are not easily detached. When combined with a multi-channel oscilloscope and a computer to form a detection circuit, it can quantitatively analyze the force applied to different zones in the battery stack package, effectively detecting potential stress concentration in the stack and reducing the risk of stack leakage and failure.

Embodiments relate to a piezoelectric ceramic and methods of making the same that is suitable for use as a high-power piezoelectric ceramic, and in particular a piezoelectric ceramic that exhibits both good hard properties and good soft properties. Embodiments involve generating the piezoelectric ceramic via the combination of chemical modification / doping and / or a texturing method so that the piezoelectric material exhibits a large figure of merit, as well as other hard and soft properties. The chemical modification involves Cu and Mn doping a piezoelectric material composition having a relaxor-lead titanate based ferroelectric structure. The texturing involves templated grain growth (TGG) texturing using a BaTiO3 (BT) template.

The application discloses a ternary ceramic material of sodium bismuth titanate- strontium titanate-lead titanate with high strain performance obtained by bismuth reduction and a preparation method thereof. The application aims at solving the problems of unstable performance of sodium bismuth titanate ceramic modified by defects, and the need of large electric field driving. The chemical general formula of the ternary ceramic material of sodium bismuth titanate- strontium titanate-lead titanate is (Na 0.5 Bi 0.5 ) 0.75(1‑x) Sr 0.25(1‑x) Pb x TiO3. The ternary ceramic material of sodium bismuth titanate- strontium titanate-lead titanate is prepared by mixing Na2CO3, SrCO3, TiO2, Bi2O3 and PbO in a stoichiometric ratio of (Na 0.5 Bi 0.5 ) 0.75(1‑x) Sr 0.25(1‑x) Pb x TiO3, and then by pressing and sintering. The maximum strain of the ternary ceramic material of sodium bismuth titanate- strontium titanate-lead titanate under an electric field of 80 kV / cm is 2.77%, and the strain memory effect is 1.75%.

A transmission line is disclosed which includes a first conductor, a second conductor, a composite disposed between the first conductor and the second conductor, the composite includes non-linear inclusions comprising one or more of non-linear dielectric and non-linear magnetic inclusions mixed in a matrix material, wherein the non-linear dielectric inclusions are selected from the group consisting of barium strontium titanate (BST), barium titanate, strontium titanate, barium zirconate titanate, lead zirconate titanate, lead titanate, lithium niobate, potassium niobate, lead scandium tantalate, strontium barium niobate, and combinations thereof, and the non-linear magnetic inclusions are selected from the group consisting of nickel zinc ferrite (NZF), manganese zinc ferrite, cobalt ferrite, manganese ferrite, zinc ferrite, nickel ferrite, and combinations thereof, wherein the non-linear inclusions by volume are about 25% NZF, about 10% BST / 15% NZF, and about 15% BST / 10% NZF, and wherein the first conductor, the second conductor, and the composite form a capacitor.

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

The application discloses a near-zero thermal expansion standard device and a preparation method and application thereof, and belongs to the technical field of metrological standard devices. The application provides a preparation method of the near-zero thermal expansion standard device, and comprises the following steps: placing PbO, TiO2 and SrO in a ball mill jar to perform first ball milling, and then performing calcination to obtain calcined powder; performing second ball milling on the obtained calcined powder, and then performing compression molding, sintering, third ball milling and secondary sintering to obtain the near-zero thermal expansion standard device. The application uses a solid phase method, adjusts and controls a perovskite lattice structure by means of A-site doped lead titanate material system, so that the thermal expansion performance is changed, meanwhile, the negative linear expansion property of the lead titanate doped with Sr is weakened, and the preparation of the near-zero expansion standard device is realized.

This invention discloses an impact-resistant insulating busbar and its preparation method, relating to the field of power electronic device manufacturing technology. The busbar of this invention comprises a substrate, an adhesive layer, and an insulating layer. The insulating layer is prepared by a specific process using furan-functionalized polyolefin elastomer, bismaleimide crosslinking agent, catechol-borate modified EVA, liquid crystal elastomer / lead zirconate titanate core-shell material, hexagonal boron nitride nanosheets, 3,4-ethylenedioxythiophene, polyethylene glycol-polystyrene-perfluorohexyl ethyl acrylate block copolymer, and other functional additives. The impact-resistant insulating busbar prepared by this invention maintains excellent electrical insulation performance while also possessing high impact resistance, excellent heat resistance, long-term environmental stability, and interface reliability, making it suitable for power equipment operating under harsh conditions.

The application discloses a high-temperature piezoelectric ceramic material, a preparation method and application, and belongs to the high-temperature piezoelectric ceramic material field. The application provides a high-temperature piezoelectric ceramic material, which is a samarium oxide doped lead ytterbium niobate-lead titanate piezoelectric ceramic material. The material is prepared by doping Sm2O3 in a lead ytterbium niobate-lead titanate binary system, and has high Curie temperature and further improved piezoelectric performance. Meanwhile, compared with existing ceramics, the piezoelectric performance of the ceramic at high temperature is more excellent. The application provides a preparation method of the high-temperature piezoelectric ceramic material, which can avoid the occurrence of a second phase in the ceramic, successfully realize stable sintering of the PYN-PT based material, and the ceramic prepared by the method has uniform particle size and high density. The preparation method has the advantages of simple process, low sintering temperature, low cost and suitability for large-scale industrial production, and has a wide application prospect in the field of high-temperature piezoelectric materials and devices.

The invention discloses a PTC (Positive Temperature Coefficient) composite material as well as a preparation method and application thereof, and relates to a PTC material technology, barium titanate, lead titanate, niobium oxide, ruthenium oxide and tantalum pentoxide are modified by KH550, then the modified materials, polypyrrole and epoxy resin are added into DMF (Dimethyl Formamide), conductive carbon black and modified carbon fibers are added, ultrasonic dispersion is performed, a solvent is removed by evaporation, and hot press molding is performed to obtain the PTC composite material. The composite material has the characteristics of sensitive temperature response, large resistance switching ratio, good reproducibility and the like, overcomes the defects of large brittleness and difficult processing of the traditional ceramic PTC material, avoids the defects of small temperature coefficient and poor stability of the polymer PTC material, realizes advantage complementation and performance integration of the ceramic PTC material and the polymer PTC material, and has a wide application prospect. The processing formability, the mechanical toughness and the use reliability of the material are remarkably improved while the excellent PTC effect is maintained.

According to the large-size single crystal lead zirconate titanate thin film and the application thereof, the thin film is prepared through the following steps that S1, a PZT precursor solution is prepared through a solvothermal method, specifically, lead salt serves as a lead source, zirconium / titanium alkoxide serves as a metal source, and the uniform and stable PZT precursor solution is formed through heating dehydration, low-temperature mixing and aging treatment in an organic solvent; s2, preparing a buffer layer: sequentially depositing an oxide dielectric layer and a metal electrode layer on the silicon substrate, and controlling the atmosphere, temperature and energy parameters through vapor deposition to realize crystal orientation regulation and control; s3, the PZT precursor solution is attached to the surface of the buffer layer in a spin coating mode, high-temperature heat treatment is combined, growth of a perovskite phase oriented single crystal film is induced, and the large-size single crystal PZT film with the single perovskite phase and preferred orientation is formed. The invention provides a large-area, smooth and crack-free single-crystal PZT film which has a great application prospect.

This invention discloses a receiving flexible sensor for concrete fracture monitoring and its fabrication method, belonging to the field of solid-state electronic device technology, and relating to the preparation of flexible piezoelectric materials. The sensor size is flexibly customized according to the monitoring component. The fabrication method includes: preparing the piezoelectric functional phase of the flexible sensor using nano-scale lead zirconate titanate ceramic powder; preparing a SiO2 precursor solution; preparing a PZT / SiO2 spinning solution; preparing a flexible piezoelectric PZT / SiO2 nanofiber membrane using electrospinning; and encapsulating the flexible piezoelectric PZT / SiO2 nanofiber membrane as the sensitive layer of the sensor after drying and annealing. The fabrication process overcomes the limitations imposed by the substrate on flexibility, and the modified PZT surface activity effectively solves the problems of particle agglomeration and precipitation in the solution. This invention improves the sensor's compatibility with complex concrete, sensitively captures fracture elastic waves with a signal amplitude of up to 75 dB, and enables timely detection of concrete structural failure.

A surface dielectric barrier discharge plasma ammonia synthesis apparatus is disclosed. In the apparatus, a container has an opening, an inlet for introducing nitrogen and hydrogen, and an outlet for discharging ammonia. A lead zirconate titanate dielectric plate is sealed at the opening to form a closed space with the container. A sheet metal electrode is disposed on the side of the lead zirconate titanate dielectric plate away from the container, and a hexagonal mesh stainless steel electrode is disposed on the side of the lead zirconate titanate dielectric plate closer to the container. A stainless steel L-shaped metal rod includes a first section placed inside the container as a connector for the hexagonal mesh stainless steel electrode and a second section extending perpendicularly out of the container from the first section. A discharge power supply is connected to the sheet metal electrode and the stainless steel L-shaped metal rod, causing nitrogen and hydrogen in the container to undergo a plasma reaction to generate ammonia.

This invention discloses a high Curie point, low voltage, and low resistance ceramic PTC element, its preparation method, and its application, relating to the field of ceramic PTC technology. The invention uses a solid solution system composed of barium titanate and lead titanate as the main components, controlling the molar ratio of barium to lead within the range of 0.63-0.70:0.30-0.37. This allows the Curie point of the material to be stably distributed in the high-temperature range of 240℃ to 280℃. By optimizing the doping system, a high temperature coefficient of resistance and a high step-up resistance ratio are maintained while achieving low room temperature resistance. The invention employs separate pre-firing methods, allowing barium titanate and lead titanate to be synthesized and semiconducted separately under their respective optimal temperature conditions, ensuring precise control of the Curie point. This avoids localized inhomogeneities caused by difficulties in solid solution during final mixing, achieving controllable and repeatable product performance, suitable for large-scale production. This invention successfully solves the problems of high Curie point, low voltage, and low resistance PTC element preparation difficulty and unstable performance in existing technologies, and has good prospects for industrial application.

This invention discloses a bismuth scandium aluminate-lead zirconate titanate piezoelectric ceramic and its preparation method, belonging to the technical field of piezoelectric ceramic materials. The general formula of the piezoelectric ceramic material of this invention is: xBiSc 1‑ z Al z O3-(1-x)PbZr y Ti 1‑y O3, where 0.2≤x≤0.7, 0.3≤y≤0.6; 0.45≤z≤0.55. The bismuth scandium aluminate-lead zirconate titanate piezoelectric ceramic prepared in this invention has a piezoelectric coefficient d. 33 It can reach 356 pC / N, Curie temperature up to 346℃, dielectric loss at 1 kHz frequency at room temperature is 1.60%, and the temperature stability of the system is improved, with the piezoelectric constant maintaining a change rate of less than 20% in the range of room temperature to 310℃.

The invention discloses a preparation method of a piezoelectric composite material, which comprises the following steps: selecting lead zirconium titanate nano powder, and preparing a polymer solution with the concentration of 15wt%; the preparation method comprises the following steps: dispersing lead zirconium titanate powder into a polyvinylidene fluoride solution; preparing the slurry into a thin film with the thickness of about 200 microns by adopting a tape casting process, so as to obtain a composite thin film blank; keeping the temperature at 150 DEG C for 1 hour in an inert atmosphere to promote polymer crystallization and uniform distribution of inorganic particles, so as to obtain a compact composite material film; depositing gold electrodes on two sides of the composite film by adopting a magnetron sputtering method; the composite film is placed in a silicone oil medium, an external electric field is applied for polarization, and a dynamic feedback polarization system is adopted in the polarization process; and after the polarization is completed, stabilizing for 24 hours at room temperature to obtain the final piezoelectric composite material. According to the invention, by introducing a dynamic feedback polarization system, abnormity can be identified in time, and priority ranking and targeted adjustment can be carried out, so that local over-polarization or under-polarization can be avoided.

The application relates to the target preparation technical field and provides a lead zirconate titanate target material, a preparation method thereof and a piezoelectric device. The preparation method comprises the following steps: preparing lead zirconate titanate powder; mixing, ball-milling and drying the lead zirconate titanate powder, glass powder, a dispersing agent and a solvent to obtain sintering precursor powder; performing pre-pressing treatment and hot-pressing treatment on the sintering precursor powder, then performing heat treatment in an oxygen-containing atmosphere, and finally machining to obtain the lead zirconate titanate target material. In the application, the PbO content is gradually increased from the bottom to the top of the crucible when the raw materials are filled, so as to compensate for the loss of PbO volatilization in the upper layer, thereby generating lead zirconate titanate powder with more uniform composition, then the lead zirconate titanate powder is sintered by low-temperature hot-pressing together with glass powder with a specific formula, the volatilized PbO is compensated, the accuracy of the chemical composition ratio of the target material is improved, the sintering temperature is reduced, the migration and aggregation of Pb elements in the sintering process are inhibited, the uniformity of the target material is improved, and the other components of the glass powder also improve the piezoelectric performance of the PZT target material.

The invention provides a ferroelectric material film composite sodium metal negative electrode and a preparation method and application thereof, and belongs to the technical field of sodium batteries. The ferroelectric material film composite sodium metal negative electrode comprises a sodium metal substrate and a ferroelectric material film layer, the ferroelectric material film layer tightly covers the surface of the sodium metal matrix in a physical coating mode, and a ferroelectric material in the ferroelectric material film layer is selected from at least one of barium titanate, lead zirconate titanate, potassium sodium niobate and hafnium zirconium oxide. According to the invention, the spontaneous polarization electric field characteristic of the ferroelectric material is combined, the ferroelectric material acts on the surface of the sodium metal to serve as a protective layer, and the migration rate of sodium ions is greatly increased and the polarization overpotential is greatly reduced due to the fact that electric dipoles in the film are orderly arranged to generate a built-in electric field in battery circulation. The ferroelectric material film has good mechanical strength, can protect sodium metal from being corroded by organic electrolyte, and effectively improves the cycle stability of the battery.