222 results about "Piezoelectric coefficient" patented technology

The present invention relates to multi-stake underwater transducers and arrays for the generation and reception of sound waves in water. The invention provides the design and fabrication of compact piston-type underwater transducers of low-to-mid operating frequency made of piezoelectric single crystals without the need of any pre-stress mechanism. The invention uses a multi-stake pipe-like motor section made of piezoelectric single crystals of high transverse mode piezoelectric coefficients and low acoustic impedance, and small-diameter and light head mass(es). The present invention also discloses various means of increasing the bandwidth of the multi-stake underwater transducers as well as derivative transducers and arrays made of them, including compact 2D and 3D omni-directional transducers, planar, conforming and shaped arrays of various designs, high-density arrays and low-drop-down-ratio parametric arrays of either single or dual frequency bands.

The invention discloses a lead zirconate titanate film material with an ultrahigh voltage coefficient as well as a preparation method and application of the lead zirconate titanate film material, and belongs to the technical field of electronic material development and film materials. The preparation of the lead zirconate titanate film material is realized by adopting a sol-gel spin-coating method and controlling the annealing times. The piezoelectric film material provided by the invention can be directly deposited on a Si substrate coated with metal Pt, does not need to introduce an additional buffer layer or dope any element, is short in annealing time and simple in preparation process, all required raw materials are cheap and easy to obtain, and the piezoelectric film material particularly has high orientation degree, low coercive voltage and excellent ferroelectric and piezoelectric properties, is suitable for preparing large-size (2-4 inches) wafers, and has a wide application prospect. And huge application potential is shown in the field of piezoelectric micro-electro-mechanical system (MEMS) devices.

The invention discloses an invisible appliance based on a transparent piezoelectric film and a design method thereof. A perioral muscle pressure sensor is installed on the lip / cheek lingual surface of teeth of the invisible orthodontic appliance, an occlusal force sensor is installed on the occlusal surface, and a tooth surface counter-acting force sensor is installed on the inner side tissue surface, so that dynamic changes of perioral muscle pressure, occlusal force and orthodontic force can be monitored in real time. The invisible orthodontic appliance provided by the invention integrates a sensor with high piezoelectric coefficient and high flexibility, has high sensitivity and accuracy, can be used for testing dynamic changes of orthodontic mechanics and evaluating the influence of perioral muscle pressure, occlusal force and the like on treatment during physiological processes of chewing, breathing, swallowing, language and the like of a patient; a doctor optimizes an orthodontic scheme through the PC terminal and pays attention to the association between oral functional mechanics and malocclusion, bad oral habits, bruxism, temporomandibular joint disorder and other diseases, and the efficiency and accuracy of oral health management are improved.

The invention provides hydrogel with controllable and enhanced mechanical properties and preparation and application thereof, the hydrogel mainly comprises glycine-polyvinyl alcohol and methylacryloylated fibroin, and glycine-polyvinyl alcohol crystal film powder and methylacryloylated fibroin are pre-crosslinked by ultraviolet light to obtain piezoelectric fibroin hydrogel. And performing ultrasonic treatment on the hydrogel to obtain the piezoelectric fibroin hydrogel with enhanced mechanical strength. Compared with a traditional organic piezoelectric material, the glycine-polyvinyl alcohol piezoelectric material used in the invention has a higher piezoelectric coefficient; the components of the methacrylated fibroin and the glycine-polyvinyl alcohol have good biocompatibility; the hydrogel can be used for treating cartilage defects, and the change of the mechanical strength of the hydrogel material can be regulated and controlled by applying external ultrasonic intervention time, sound intensity, frequency and the like, so that the mechanical strength of the hydrogel can dynamically adapt to different stages of repairing of movement system tissues including cartilage.

The invention belongs to the technical field of piezoelectric ceramics, and discloses a lead-free piezoelectric ceramic and a preparation method thereof. The general formula of the lead-free piezoelectric ceramic is 0.95 (K < 0.48 > Na < 0.52 >) NbO < 3-0.05 > (Bi < 0.5 > Na < 0.5 >) HfO < 3-0.002 > Fe < 2 > O < 3-x > CuO, wherein x is greater than or equal to 0.005 and less than or equal to 0.015. On the basis of constructing an orthogonal-tetragonal phase boundary (O-T phase boundary), CuO is introduced for doping, and by controlling the doping amount, not only can a defect dipole be introduced, but also multi-phase coexistence can be maintained, and a nano-scale domain can be increased. Multi-phase coexistence and a nano-scale domain ensure a relatively low polarization potential barrier, so that a high-voltage coefficient is maintained; the defect dipole can effectively inhibit domain wall movement and reduce loss; and the mechanical quality factor is obviously improved while the piezoelectric coefficient is kept at a relatively high level.

The invention relates to the technical field of nuclear reactors, and provides a nuclear reactor piezoelectric sensor sensitive material optimization method and device and a medium, and the method comprises the steps: 1, determining an initial sensitive material sample based on a sensitive material template and an initial element doping scheme; 2, performing an irradiation experiment on the initial sensitive material sample, and determining irradiation parameters corresponding to the initial sensitive material sample based on an experiment result; 3, determining the average parameter change rate of the sample based on the irradiation parameters corresponding to the plurality of initial sensitive material samples and the high-temperature performance parameters corresponding to the plurality of initial sensitive material samples subjected to the irradiation experiment, and judging whether the average parameter change rate of the sample is smaller than a preset threshold value or not; if yes, determining the initial sensitive material sample as a target optimization sensitive material; and if not, adjusting the initial element doping scheme, and returning to the step 1. According to the embodiment, the piezoelectric coefficient of the piezoelectric sensitive material in a high-temperature nuclear radiation environment is improved, and the fault monitoring precision of key equipment of a nuclear reactor is improved.

The present disclosure provides a multi-coefficient coupled-mode surface acoustic wave resonator and a manufacturing method therefor. During operation of the surface acoustic wave resonator, at least two different piezoelectric coefficients are coupled and jointly excite acoustic waves. The multi-coefficient coupled-mode surface acoustic wave resonator comprises: a substrate; a piezoelectric layer, provided on the substrate; an electrode unit, provided on the surface of the piezoelectric layer and comprising at least one interdigital electrode pair; and a reflective grating unit, comprising at least two grating structures which are symmetrically arranged on the two sides of the electrode unit, wherein the equivalent density of the electrode unit is greater than 4000kg / m3. The electric field distribution is changed by changing the mass loading effect of the interdigital electrode pair and the ratio of the electrode wavelength to the thickness of the piezoelectric layer, such that at least two piezoelectric coefficients are mutually coupled to jointly excite acoustic waves, thus achieving the surface acoustic wave resonator having an electromechanical coupling coefficient exceeding 25%.

The present invention provides a small molecule organic piezoelectric material based on phenylalanine derivatives, a preparation method and an application. The preparation method includes the following steps: dissolving an organic small molecule of a phenylalanine derivative in an alcohol solvent to obtain a mixed solution; adding acids of different types and molar ratios to the mixed solution to dope the organic small molecule; and volatilizing the solvent and assembling the organic small molecule to obtain an organic piezoelectric material with different piezoelectric coefficients. The organic small molecule assembly synthesized by the present invention has piezoelectric properties, and the piezoelectric performance can be adjusted by means of acid doping. The preparation method is simple, efficient and environmentally friendly. The piezoelectric device prepared by the method can effectively monitor human movement and can be used in the fields of electronic skin, soft robots, health monitoring, motion monitoring, wearable devices and the like.

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.

The invention provides a piezoelectric elastomer material and a preparation method and application thereof, and relates to the technical field of piezoelectric materials. The piezoelectric elastomer material comprises piezoelectric molecular crystals and a polymer elastic matrix, the polymer elastic matrix forms an elastic skeleton of a three-dimensional network structure, and the piezoelectric molecular crystals are connected to the three-dimensional network structure through hydrogen bonds and are filled in pores of the elastic skeleton. The piezoelectric molecular crystal comprises hexafluoropentanediol or dodecafluorononanediol, the polymer elastic matrix comprises a degradable waterborne polyurethane polymer or a degradable polyester polymer, and the mass ratio of the piezoelectric molecular crystal to the polymer elastic matrix is (0.2-3): 1. The piezoelectric elastomer material has enough strength and hardness, good elasticity and flexibility, high piezoelectric coefficient, excellent biocompatibility and safe degradability or can be discharged out of a body through a biological metabolism system, and the biological safety problem of the piezoelectric material in application in the field of biomedicine is solved.

The invention provides a piezoelectric ceramic composite material and a preparation method thereof, the chemical composition of the piezoelectric ceramic composite material is (1-x) Pb (Ni1 / 3Nb2 / 3) O3-x Pb (ZrTi) O3-y MnO2-MeOz-Li2CO3-Bi2O3-PbmOn, x is 0.4-0.99, and represents the molar ratio of Pb (ZrTi) O3 in a Pb (Ni1 / 3Nb2 / 3) O3-Pb (ZrTi) O3 system, and y represents the molar ratio of Pb (ZrTi) O3 in the Pb (Ni1 / 3Nb2 / 3) O3-Pb (ZrTi) O3 system. The molar ratio of Zr to Ti is 30 / 70 to 60 / 40; y is 0.01 wt%-1wt% and represents the weight percentage of MnO2 in the (1-x) Pb (Ni1 / 3Nb2 / 3) O < 3-x > Pb (ZrTi) O < 3-y > MnO2 system; according to the PNN-PZT piezoelectric ceramic composite material disclosed by the invention, low-temperature sintering is realized by utilizing a synergistic effect of MnO2, PbmOn and an additional sintering agent, and the sintering temperature of the PNN-PZT piezoelectric ceramic composite material is reduced to 950 DEG C or below; compared with the traditional PZT ceramic, the piezoelectric ceramic composite material disclosed by the invention has higher dielectric constant and piezoelectric coefficient in a wide PNN component range, and also has higher mechanical quality factor Qm, lower dielectric loss and high dielectric constant.

Bulk acoustic wave resonators are presented. Such resonators typically operate based on a dynamic nonuniform effective piezoelectricity in composite multilayer ferroelectrics with large electrostriction coefficients, like barium strontium titanate (BST). Harmonic resonance modes of a multilayer bulk acoustic wave resonator can be selectively excited with an electromechanical coupling coefficient equal to the fundament mode, which is contrary to the trend K2∝1 / n2 exhibited by conventional piezoelectric bulk acoustic resonators. Such a resonator allows for the design of a new class of band-switching filters.

The invention belongs to the related technical field of composite flexible piezoelectric materials, and discloses a piezoelectric polymer film material, a preparation method thereof and a piezoelectric sensor. The preparation method comprises the following steps: S1, selecting a polyvinylidene fluoride non-relaxor ferroelectric polymer and a polyvinylidene fluoride relaxor ferroelectric polymer, the preparation method comprises the following steps: respectively dissolving a polyvinylidene fluoride based non-relaxor ferroelectric polymer and a polyvinylidene fluoride based relaxor ferroelectric polymer in an organic solvent to obtain two polymer solutions; s2, blending and stirring the two polymer solutions to obtain a mixed solution; s3, the mixed solution is poured into a mold, the solvent is dried, and the piezoelectric polymer membrane material is prepared. The relaxor ferroelectric polymer is introduced into the non-relaxor ferroelectric polymer through physical blending design, the problem that the piezoelectric coefficient of a traditional vinylidene fluoride polymer is remarkably reduced in a high-temperature environment is solved, the prepared membrane material does not need complex chemical modification, the process is simple, the cost is low, and good operability is achieved.

The invention discloses a piezoelectric ceramic with high Curie temperature and high temperature stability and a preparation method thereof, the composition general formula of the piezoelectric ceramic is xPb (In1 / 2Nb1 / 2) O3-yPbZrO3-(1-x-y) PbTiO3, the value range of x is 0.20-0.50, and the value range of y is 0.10-0.30. The high Curie temperature, the large piezoelectric coefficient and the high coercive field are achieved, the temperature stability of the excellent piezoelectric property at the room temperature to 300 DEG C is achieved, the change rate of the inverse piezoelectric coefficient within the range from the room temperature to 180 DEG C is only 1.4%, and the change rate of the electromechanical coupling coefficient kp within the temperature range from the room temperature to 275 DEG C is only 4.2%.

The invention discloses an acoustic resonator and a filter, and relates to the technical field of radio frequency, the acoustic resonator comprises a substrate, a coupling adjustment layer, a piezoelectric layer and an interdigital electrode, the material of the piezoelectric layer and the tangential direction of the piezoelectric layer are selected, and the value range of an in-plane Euler angle alpha is set; the piezoelectric coefficient of the piezoelectric layer comprises an e11 component and an e34 component in a piezoelectric coefficient matrix, so that the excited sound wave of the piezoelectric layer at least comprises a longitudinal mode sound wave mainly excited by the e11 component and a high-order shear mode sound wave mainly excited by the e34 component; and a coupling adjustment layer which is made of a proper material and has a proper thickness ratio with the piezoelectric layer is arranged, so that the resonance of the longitudinal mode sound wave and the high-order shear mode sound wave is adjusted to the same frequency, coupling is achieved, and finally the sound wave comprising two coupling modes which are mutually orthogonally polarized in a specific propagation direction is excited. The requirements for high frequency and large bandwidth of centimetric wave communication frequency bands are met, the device is simple in structure, and the preparation complexity and cost of the device can be reduced.

The invention relates to the field of piezoelectric ceramic materials, in particular to a piezoelectric ceramic material with high Curie temperature and high piezoelectric coefficient and a preparation method thereof, the structural formula of the piezoelectric ceramic material is as follows: (1-x-y) (Bi2O2) < 2 + > (Am-1BmO3m + 1) < 2-x > LiTaO3-yLaAlO3, A is any one or more of Na < + >, K < + >, Ca < 2 + >, Sr < 2 + >, Ba < 2 + >, Pb < 2 + >, Bi < 3 + > and La < 3 + >; b is any one or more of Fe < 3 + >, Ti < 4 + >, Nb < 5 + > and W < 6 + >; m is an integer between 1 and 4; 0 < x < = 0.2; 0 < y < = 0.2, the piezoelectric ceramic material prepared by the method has high Curie temperature and excellent electrochemical performance, the maximum piezoelectric constant can reach 35pC / N, and compared with the currently reported bismuth layered structure piezoelectric ceramic, the piezoelectric ceramic material has the advantage that the piezoelectric constant is greatly improved.

An optical element includes a first piezoelectric layer of fluorinated polymer with a piezoelectric coefficient, d31, of at least 25 pC / N and an electrode layer disposed on the first piezoelectric layer. An optical characteristic of the optical element changes when the first piezoelectric layer is deformed upon application of a voltage at the electrode layer.

A lead-free titanate textured ceramic material having both low sintering temperature and high piezoelectric performance and a preparation method and application thereof, relating to a lead-free titanate textured ceramic material and a preparation method and application thereof. The problem of enhancing the piezoelectric performance of BT-based ceramic materials under the prior art is that the piezoelectric performance of the ceramic materials is increased at the Curie temperature T c The material chemical formula is (Ba 1‑x Ca x )(Ti 1‑ y B y )O3‑zwt.%M, the elements in the grains are evenly distributed and there is no core-shell structure, the preferred orientation degree is above 96%, the piezoelectric coefficient is above 800pC / N, the field-induced strain coefficient is above 2000pm / V, and the electromechanical conversion factor is 22.0×10 ‑12 m 2 / N or more, and Curie temperature is above 80℃. Methods: 1. Preparation of matrix powder; 2. Preparation of tape casting slurry; 3. Preparation of textured ceramics. Applied in high-performance multilayer environmentally friendly piezoelectric components.

Provided in the present disclosure are a multi-coefficient coupled mode-based surface acoustic wave resonator and a manufacturing method therefor, which can be applied to the technical field of resonators. The multi-coefficient coupled mode-based surface acoustic wave resonator comprises a substrate; a piezoelectric layer arranged on the substrate, the tangential direction of the piezoelectric layer being a Z tangential direction, a piezoelectric coefficient matrix that corresponds to the piezoelectric layer at least comprising a non-zero first piezoelectric coefficient e15 and second piezoelectric coefficient e16 and, under the action of a transverse electric field and on the basis of the first piezoelectric coefficient e15 and the second piezoelectric coefficient e16, the coupled mode of the piezoelectric layer being excited; and at least two interdigital electrodes arranged on the piezoelectric layer, the ratio of the center distance of the two adjacent interdigital electrodes to the thickness of the piezoelectric layer being 0.25-5, and the ratio of the thickness of each interdigital electrode to the thickness of the piezoelectric layer being less than 0.5.

The application belongs to the technical field of flexible piezoelectric materials, and discloses a grafted ferroelectric polymer thin film with a high piezoelectric coefficient and a preparation method thereof, wherein the preparation method comprises the following steps: obtaining a polymer solution by selecting a polyvinylidene fluoride-based ferroelectric polymer; adding a grafting agent reagent to the polymer solution and uniformly mixing to obtain a mixed solution; uniformly casting the mixed solution on the surface of a glass substrate, heating in an oven to volatilize the solvent, then increasing the temperature of the oven to perform a grafting reaction to obtain a grafted thin film; after the oven is naturally cooled to room temperature, the grafted thin film is peeled off from the glass substrate, and a polarization process is adopted to obtain the grafted ferroelectric polymer thin film with a high piezoelectric coefficient. The polyvinylidene fluoride-based ferroelectric polymer is modified by grafting side chains, the relative stability of different molecular conformation energies in the ferroelectric polymer is regulated by grafting side chains in the polymer, the ferroelectric phase and the relaxor phase in the ferroelectric polymer are induced to compete with each other, and the piezoelectric coefficient of the material is significantly improved.

The invention discloses a piezoelectric effect finite element modeling method considering electric field and rate related hysteresis characteristics, belongs to the technical field of piezoelectric driving theories, and aims to solve the problem that a finite element model with a fixed piezoelectric coefficient is large in error during displacement analysis. A piezoelectric effect finite element modeling method which adopts a time-varying piezoelectric coefficient and considers electric field and rate-dependent hysteresis characteristics is provided, and accurate description of piezoelectric displacement under excitation of different electric signals is realized. Comprising the following steps: S1, piezoelectric displacement measurement; s2, identifying a hysteresis model and parameters; s3, regression fitting of the hysteresis model; and S4, finite element modeling. According to the modeling method of the piezoelectric ceramic finite element model, the hysteresis model is combined with the piezoelectric constitutive equation in the finite element model, the modeling method of the piezoelectric ceramic finite element model considering the hysteresis characteristic is provided, and the established finite element model can accurately predict output displacement tracks under different electric signal excitation and force-electricity coupling excitation in the simulation process; and the method has a certain promotion significance on the research of shearing piezoelectric ceramic analog simulation.

The invention discloses a method for preparing a ceramic membrane by using surface tension. Relates to the technical field of ceramic membrane preparation. A method for preparing a ceramic membrane comprises the following steps: S1, immersing a grid frame made of a hydrophilic material into a ceramic membrane precursor colloidal solution, lifting the grid frame from the ceramic membrane precursor colloidal solution, and enabling the ceramic membrane precursor colloidal solution to suspend in gaps of grids to form a liquid bridge, so as to obtain a sample; and S2, drying the sample, and when the liquid bridge is converted into a gel state or an amorphous solid film, sintering the sample to obtain the ceramic film. According to the method disclosed by the invention, the ceramic membrane with any required thickness, no crack and excellent piezoelectric coefficient can be manufactured.

The invention belongs to the technical field of microelectronic devices, and discloses an optimization method of a high-thickness hafnium-based piezoelectric film device, the thickness of a hafnium-based piezoelectric functional layer of the high-thickness hafnium-based piezoelectric film device is not less than 20nm, and the hafnium-based piezoelectric functional layer is of a superlattice structure formed by alternately laminating hafnium oxide and zirconium oxide; the piezoelectric performance of the high-thickness hafnium-based piezoelectric film device is optimized by depositing a third oxide layer at the interface of two adjacent superlattice units every other preset thickness in the hafnium-based piezoelectric functional layer; the third oxide layer is selected from an aluminum oxide layer and a silicon oxide layer. The third oxide layer is inserted into the superlattice laminated structure formed by alternately laminating high-thickness hafnium oxide and zirconium oxide, so that the formation of large grains in the hafnium-based piezoelectric film can be inhibited, the formation of an m-phase structure without piezoelectric property in the hafnium-based film is inhibited, the increase of non-centrosymmetric o-phase structures in the film is promoted, and the piezoelectric property of the film is improved. Therefore, the piezoelectric coefficient of the whole device is improved, and the piezoelectric property of the high-thickness hafnium-based piezoelectric film device is optimized.

Aspects of this disclosure relate to a bulk acoustic wave resonator having an acoustically active region and a peripheral region. The bulk acoustic wave resonator can include a first electrode, a second electrode, a piezoelectric layer positioned between the first electrode and the second electrode, and a recessed frame structure at least partially in the acoustically active region. The piezoelectric layer can have an effective piezoelectric coefficient with a lower magnitude in the peripheral region than in the acoustically active region. Other embodiments of bulk acoustic wave resonators are disclosed. Related filters, multiplexers, radio frequency modules, radio frequency systems, wireless communication devices, and methods are disclosed.

Disclosed in the present invention is a domain wall straightening method for a periodically poled ferroelectric crystal. In the present invention, by means of testing a piezoelectric coefficient of a poled sample, the poling situation of the sample can be non-destructively determined, and regions with uniform poling can be selected; moreover, whether to continue poling or terminate poling and restart poling after single-domain formation can be determined on the basis of a duty cycle calculation result; and the straightness of domain walls is determined on the basis of the variation of the piezoelectric coefficient, such that the magnitude and duration of a poling voltage are adjusted in a timely manner, thereby accurately controlling a poling process, and thus obtaining a high-quality periodically poled crystal.

A method of calculating a drive speed of a piezoelectric actuator, the piezoelectric actuator comprising an impact drive system and a driven member, the impact drive system comprising a fixing member, a piezoelectric element, and a shaft connected in this order and the driven member being provided on the shaft to be moveable along a longitudinal axis direction of the shaft, wherein the piezoelectric element is disposed on one surface of the fixing member to be extendable and shrinkable in a direction perpendicular to the surface of the fixing member, wherein the shaft is disposed in a direction perpendicular to and on a surface of the piezoelectric element opposite to a surface facing the fixing member, and wherein the piezoelectric element provides a movement of the driven member when a voltage is applied to the piezoelectric element, the method comprising calculating a drive speed Sp by the following equation (II) : Sp = μ *2 *f *αv *αs *αf ··· (II) where μ is a displacement of the piezoelectric element calculated by the following equation (III), f is a frequency of a voltage applied to the piezoelectric element, αv is a speed distribution coefficient calculated by the equation (I), αs is a shaft damping coefficient, and αf is a transfer efficiency of a displacement of the driven member by one cycle of extension and shrink of the piezoelectric element, αv = (Mw + Mp) / (Mw + 2 *Mp + Ms) ··· (I) where Mw is a mass of the fixed member, Mp is a mass of the piezoelectric element, and Ms is a mass of the shaft, μ = n *V *d33 *k··· (III) where n is a number of layers of the piezoelectric element, V is an input voltage applied to the piezoelectric element, d33 is a piezoelectric coefficient, and k is a linear compensation coefficient.

Relaxation lead-based textured ceramic material with low texture temperature and high electrical performance, preparation method and application thereof relates to relaxation lead-based textured ceramic material and preparation method and application thereof. The problem of high texture temperature of low Zr content ceramic, orientation grain presenting core-shell structure, high Zr content ceramic being difficult to be textured with high quality, leading to high voltage electrical performance and low texture temperature of ceramic being unable to be acquired simultaneously is solved. Chemical formula (1-x-y) Pb (A, Nb) O3-x Pb Zr O3-y Pb Ti O3 is prepared at 850 DEG C-1095 DEG C, the texture Zr content can reach more than 50%, along [001] c The orientation degree is greater than 96%, the grain misplacement degree is less than 0.20, there is no core-shell structure, the Curie temperature is greater than or equal to 200 DEG C, the quasi-static piezoelectric coefficient is greater than 1000 pC / N, and the electromechanical coupling coefficient is greater than 0.85. The method comprises the following steps: preparing a mother body fine powder, preparing a ceramic green body by flow casting and stacking and pressing, and preparing a textured ceramic. The method is used in a multilayer piezoelectric device.

The invention belongs to the technical field of piezoelectric ceramic materials, and discloses a hard piezoelectric ceramic preparation method based on oxidation-reduction treatment, which comprises the following steps: sintering a piezoelectric ceramic green body with the component of Ba (1-x) EuxTi (1-x / 8O3) in a reducing atmosphere to obtain BT piezoelectric ceramic (x = 0.015-0.04); and carrying out oxidation treatment on the BT piezoelectric ceramic in an air atmosphere at 1200-1350 DEG C to obtain the hard piezoelectric ceramic. According to the invention, an additional driving force is provided through an oxidation-reduction reaction, so that a solute is separated out in a precipitation phase in a solid solution with relatively low content, the limitation of component regulation and control is solved, and a relatively good piezoelectric coefficient is achieved while the electromechanical coupling performance is optimized.

The invention relates to a hydrophobic tripeptide molecule, a crystal constructed by the hydrophobic tripeptide molecule and application of the hydrophobic tripeptide molecule in a piezoelectric device. The structural formula of the polypeptide molecule is shown as a formula (I). The polypeptide molecule can form a micron-sized crystal through a heating-cooling method, and the interior of the micron-sized crystal is of an asymmetric structure and is of a triclinic system. A crystal formed by the polypeptide molecule has a relatively high piezoelectric coefficient (21.5 pC / N), a sandwich type piezoelectric device is constructed by using the crystal, and the output voltage can reach 2.57 V, which is the highest value of an oligopeptide nano material prepared in an aqueous solution. Therefore, the invention provides a method for forming the tripeptide crystal, and provides a potential strategy for development of piezoelectric materials based on short peptide self-assembly. (I)

The invention belongs to the technical field of piezoelectric ceramics, and particularly relates to a lead antimonate niobate-lead manganese niobate-lead zirconate titanate piezoelectric ceramic material and a method. Comprising a chemical general formula of xPb (Sb1 / 3Nb2 / 3) O3 <-0.04 > Pb (Mn1 / 3Nb2 / 3) O3 <-(0.96-x) Pb < 0.98 > Sr < 0.02 > (Zr < 0.5 > Ti < 0.5 >) O3 < + y wt% Fe < 2 > O < 3 >, wherein x is equal to 0.01 to 0.08, and y is equal to 0.01 to 2. The piezoelectric ceramic material is prepared from the following raw materials: Pb3O4, TiO2, ZrO2, Nb2O5, Sb2O3, MnO2 and SrCO3. The piezoelectric ceramic has a high piezoelectric coefficient and a high electromechanical coupling coefficient at the same time, compared with traditional P-8 series piezoelectric ceramics, the energy conversion rate can be improved, and the piezoelectric ceramic has low dielectric loss and high mechanical quality factor together with P-8 and has low loss in the energy conversion process.