53 results about "Sodium niobate" patented technology

The invention discloses a perovskite-type potassium-sodium niobate-based composite ceramic and a preparation method thereof, the perovskite-type potassium-sodium niobate-based composite ceramic is prepared from two kinds of lead-free piezoelectric ceramics, which are 0.965 (K < 0.48 > Na < 0.52 >) (Nb0.955 Sb < 0.045 >) O < 3 >-0.035 (Bi < 0.5 >, Na < 0.5 >) HfO3 and (K < 0.5 > Na < 0.5 >) NbO < 3 >-1% mol Cu, and the two kinds of lead-free piezoelectric ceramics are firstly pre-synthesized into powder and then mixed, dried and sintered to prepare the perovskite-type potassium-sodium niobate-based composite ceramic. The potassium-sodium niobate-based composite ceramic prepared by mixing potassium-sodium niobate-based ceramic powder of two different systems according to different molar ratios, dry-pressing and sintering has excellent piezoelectric property, good temperature stability and good mechanical quality factor, the piezoelectric constant d33 of the potassium-sodium niobate-based composite ceramic is 254 pC / N, kp reaches 0.51, Qm is 173, and Tc is 304 DEG C.

A positive electrode material, and a preparation method therefor and the use thereof. The positive electrode material comprises a positive electrode base material and a coating layer that coats the surface of the positive electrode base material. The positive electrode base material has a general chemical formula of AaMexMnyO2, wherein A comprises Na and / or Li; 0.6≤a≤1, 0.1≤x≤0.4, 0.2≤y≤0.6, and x+y=1; and Me comprises a transition metal element. The coating layer comprises sodium niobate. The distribution of elements in the positive electrode material is uniform; and after coating with sodium niobate, not only is the effect of isolating the positive electrode material from an electrolyte achieved, but the dynamic performance and safety performance of the positive electrode material are also improved.

The general formula of the potassium-sodium niobate-based leadless piezoelectric ceramic material is x (K < 0.495 > Na < 0.505 >) Sr < 0.02 > Nb < 0.99 > Sn < 0.01 > O < 3-y > mol% ZrO2, x is greater than or equal to 0.92 and less than or equal to 0.94, and y is greater than or equal to 0.8 and less than or equal to 1.5. The invention also discloses ceramic slurry containing the potassium sodium niobate-based lead-free piezoelectric ceramic material, and a prepared piezoelectric ceramic layer and nickel inner electrode co-fired type lead-free ceramic laminated actuator. According to the invention, Zr ions are introduced to enhance the anti-reduction characteristic of a KNN-based lead-free ceramic matrix, the high strain response activity of a perovskite A-site vacancy defect dipole is fully utilized, the nickel inner electrode co-fired type lead-free piezoelectric ceramic laminated actuator with high electrostrictive displacement output characteristic is obtained in a reduction sintering atmosphere, and the piezoelectric ceramic laminated actuator has excellent driving performance and can be applied to the field of piezoelectric ceramics. Good linear correlation exists between displacement output and driving voltage amplitude.

The invention relates to a high-entropy ceramic capacitor, a ceramic dielectric material for the high-entropy ceramic capacitor and a preparation method, the raw material composition of the ceramic dielectric material comprises NaNbO3, (Na0. 2Bi0. 2Ba0. 2Mg0. 2Zn0. 2) TiO3, H3BO3, CaZrO3 and the like, by controlling the raw material ratio and preparation process parameters of sodium niobate and adopting a multi-step grinding synthesis method, NaNbO3-based high-entropy ceramic is designed, so that the insulation resistance of the high-entropy ceramic capacitor is effectively improved; on the other hand, chemical modification treatment is carried out by introducing (Na0. 2Bi0. 2Ba0. 2Mg0. 2Zn0. 2) TiO3, H3BO3, CaZrO3 and the like, so that the structural stability of an antiferroelectric phase is enhanced, the compactness of the material is improved, and finally, the energy storage performance of the material is optimized and improved.

The invention belongs to the technical field of ceramic materials, and particularly relates to a niobate-based lead-free dielectric energy storage ceramic material as well as a preparation method and application thereof. The chemical formula of the dielectric energy storage ceramic material is (NaNbO3) (1-x) [(Ba1 / 3Ca1 / 3Sr1 / 3) (Zr1 / 2Ti1 / 2) O3] x, and x is larger than or equal to 0.01 and smaller than or equal to 0.2. An entropy modulation component is introduced into a niobate system, a nano polar island is constructed, and reversible quick response of the ceramic material to an electric field is achieved. The electrical microstructure of the sodium niobate ceramic is optimized, so that the relaxation time distribution of the material is normalized, and a structural basis is provided for excellent electrical properties. High energy storage performance is achieved in a wide temperature range, the energy storage density is 12 J cm <-3 >, and the energy storage efficiency is 95%.

The application relates to the technical field of piezoelectric ceramic devices, and particularly discloses a super-high inverse piezoelectric performance anti-reduction sodium potassium niobate-based lead-free piezoelectric ceramic with a chemical formula of (1-x)(Na 1‑y K y ) z Nb 1‑h Ta h O3-xAZr t O3+i% M+k% N, wherein x, y, z, h, t, i and k represent molar fractions, 0.04<=x<0.08, 0.45

The application relates to a potassium-sodium niobate-based lead-free piezoelectric ceramic, the components of the potassium-sodium niobate-based lead-free piezoelectric ceramic are (1-x)K 0.48 Na 0.55 Bi a Nb 0.96 Zr b Sb c O3-a-b-c-CuOx; wherein 0.01<=a<=0.08, 0.02<=b<=0.08, 0.02<=c<=0.08, 0.001<=x<=0.2, x represents the molar fraction of CuO, the application can effectively improve the ceramic oxygen vacancy concentration and enhance the pinning effect of the ceramic ferroelectric domain wall by regulating the proportion of copper oxide, so that a potassium-sodium niobate-based lead-free piezoelectric ceramic with moderate d 33 And high mechanical quality factor Qm is obtained, which is expected to be applied in the field of lead-free medium-power piezoelectric devices. In addition, the process for preparing the potassium-sodium niobate-based lead-free piezoelectric ceramic is simple, the cost is low, and the application has the potential for industrial application.

The invention relates to the field of dielectric energy storage ceramic materials, in particular to potassium-sodium niobate-based energy storage ceramic as well as a preparation method and application thereof. The chemical composition of the potassium-sodium niobate-based energy storage ceramic comprises (1-x) (0.55 K0. 5Na0. 5NbO3-0.45 BaTiO3)-x (Bi0. 5yNa0. 5 + y) Ti0. 9Zr0. 1O3, x is more than 0 and less than or equal to 0.4, and y is more than or equal to-0.05 and less than or equal to 0.1. The potassium-sodium niobate-based energy storage ceramic still keeps excellent energy storage efficiency while having high energy storage density, and can meet the use requirements to a greater extent, specifically, at the room temperature of 100 Hz, the energy storage density of the potassium-sodium niobate-based energy storage ceramic is 7.02 J / cm < 3 >-10.55 J / cm < 3 >, and the energy storage efficiency is 91.7%-94.2%.

The application discloses an iron-based barium sodium niobate ceramic material with high energy storage performance and a preparation method thereof. 4‑2x Sm 2x Na2Fe x Nb 10‑x O 30 , wherein 1<=x<=1.25. Barium carbonate, samarium oxide, sodium carbonate, ferrous oxide and niobium pentoxide are used as raw materials, and a standard solid-phase method is adopted to sinter the iron-based barium sodium niobate ceramic material. In the product formula, iron is used to replace niobium in the barium sodium niobate, which is lead-free, environment-friendly, rich in iron reserves and low in price, and is beneficial to control the cost of raw materials. In addition, the iron replacement is beneficial to enhance the relaxor ferroelectric performance of the material, can obtain a more slender hysteresis loop, and improves the energy storage efficiency of the material. The prepared ceramic material has few pores and cracks, high density, and the microstructure is obviously improved, the grain size is more fine and uniform, the ferroelectric polarization intensity and the breakdown field strength are significantly improved, the problem that the barium sodium niobate material is difficult to sinter is solved, and the ferroelectric performance and the energy storage performance are significantly improved.

The invention provides a lead-free piezoelectric ceramic material, a preparation method thereof and a piezoelectric device. The lead-free piezoelectric ceramic material is represented by a chemical general formula as follows: (1-x-y) (K1-aNaa) (Nb1-bMb) O < 3-x > AWO < 4-y > BMoO < 4 >, wherein (K1-aNaa) (Nb1-bMb) O3 represents a potassium-sodium niobate-based ceramic material, a is greater than or equal to 0.4 and less than or equal to 0.6, b is greater than or equal to 0 and less than or equal to 0.1, and M is a doped metal element; x and y are mole fractions and satisfy 0 lt; x is less than or equal to 0.05, 0lt; y is less than or equal to 0.05, and 0 lt; x + y < = 0.1; the AWO4 is tungstate, and the BMoO4 is molybdate. Through the synergistic effect of tungstate and molybdate, the sintering temperature of the lead-free piezoelectric ceramic material is reduced, the piezoelectric constant of the lead-free piezoelectric ceramic material is improved, the dielectric loss of the lead-free piezoelectric ceramic material is reduced, the comprehensive performance of the lead-free piezoelectric ceramic material is greatly improved, and the lead-free piezoelectric ceramic material can be applied to piezoelectric devices such as piezoelectric motors with high requirements for piezoelectric performance.

The application provides a bone repair material and a preparation method and application thereof, and the bone repair material comprises an oxygen vacancy sodium niobate cerium dioxide heterojunction; the oxygen vacancy sodium niobate cerium dioxide heterojunction comprises the following molar amounts of raw material components: 3-5 moles of oxygen vacancy sodium niobate; 1 mole of cerium dioxide. The bone repair material has excellent piezoelectric properties, sonodynamic properties and enzyme-like activity, can promote the proliferation and osteogenic differentiation of bone cells, significantly improve the expression of osteogenic genes, and has a significant bactericidal / biofilm infection removal effect, and has application potential in the field of infected bone defects as an antibacterial bone repair material.

This invention relates to the field of piezoelectric materials and discloses a method for preparing a potassium sodium niobate thin film. The method involves first synthesizing a ceramic target material from niobium pentoxide, potassium carbonate, and sodium carbonate in a solid phase; then placing the ceramic target material in a magnetron sputtering apparatus for sputtering to form an amorphous thin film; finally, adding the amorphous thin film to an annealing atmosphere in a crucible for annealing to form a potassium sodium niobate thin film. This method uses magnetron sputtering to prepare an amorphous potassium sodium niobate thin film under conditions below the film crystallization temperature, followed by annealing to crystallize the film. During annealing, an alkali metal atmosphere is used to compensate and control the alkali metal elements in the film. This method is still based on magnetron sputtering, which is suitable for large-size thin film growth, offering strong process controllability and high production efficiency. The alkali metal atmosphere compensation allows for control of the alkali metal element composition in the potassium sodium niobate.

The invention discloses a sodium niobate / molybdenum diselenide heterojunction and a preparation method and application thereof. The invention provides a sodium niobate / molybdenum diselenide heterojunction which comprises manganese-doped sodium niobate and molybdenum diselenide, and the ion molar ratio of Nb to Mo in the manganese-doped sodium niobate and molybdenum diselenide is 1.5: (0.5-3). The doped sodium niobate / molybdenum diselenide heterojunction has high piezoelectric performance and sonodynamic performance and has enzyme-like activity, under high-power ultrasonic driving, the sonodynamic and enzyme-like activity of the material is enhanced through the piezoelectric effect of the material, multiple ROS are generated, bacteria are killed in a synergistic mode, and biological membranes are removed; under the driving of low-power ultrasonic waves, oxidative stress materials are relieved, osteoblasts are proliferated and differentiated, and potential application prospects are achieved in the aspect of treating infectious bone tissues.

The invention relates to the field of piezoelectric ceramic materials, in particular to potassium-sodium niobate-based piezoelectric ceramic and a preparation method thereof, the chemical structure of the potassium-sodium niobate-based piezoelectric ceramic is as follows: (1-alpha-beta) Lix (Na1 / 2K1 / 2) 1-xNb1-y (W1 / 2Mn1 / 2) yO3-alpha (Ln2-zSrz) CuO4-beta Bi2O3, Ln is a lanthanide rare earth element; 0 < x < = 0.1, 0 < y < = 0.1, and 0 < z < = 0.5; 0 < alpha < = 0.05, 0 < beta < = 0.05, and the potassium-sodium niobate-based piezoelectric ceramic prepared by the method has excellent piezoelectric properties and has wide application prospects in the fields of transduction, filtering, ultrasonic detection and the like.

The invention relates to a high-energy-storage sodium niobate-based temperature-stable ferroelectric multilayer energy-storage ceramic capacitor and a preparation method thereof, the chemical general formula of the capacitor is (Na < 0.75-x > Bi < 0.125 > Li < 0.125 > Nb < 0.75-xy-xz > Ti < 0.25 >)-xBa (PyQz) O3, x is more than or equal to 0.01 and less than or equal to 0.06, and x is more than or equal to 0.01 and less than or equal to 0.06. Y is greater than or equal to 0.01 and less than or equal to 0.02; the value range of z is more than or equal to 0.01 and less than or equal to 0.04, P is one or a combination of more than one of Mg, Ni, Ta and Sb, Q is one or a combination of more than one of Mn, Nb and Zr, the average grain size of the energy storage ceramic capacitor is in a micron order, the average thickness of the dielectric layer is 8-15 microns, and the capacitor can release energy storage density (Wrecc) gt; the energy storage efficiency (eta) is greater than 85%; the change rate of Wrec and eta in the test temperature range of 20-200 DEG C is less than 8%; and the change rate of Wrec and eta in the test frequency range of 0.5-240 Hz is less than 6%.

The invention discloses a sodium niobate-based ferroelectric ceramic and a preparation method thereof, and belongs to the field of dielectric ceramics. The chemical composition general formula of the sodium niobate-based ferroelectric ceramic is (Na < 0.874-0.874 x > Yb < 0.0085-0.0085 x > Tm < 0.0085-0.0085 x > Bi < 0.075-0.75 x > Ba < 0.5 a > Sr < 0.5 b >) (Nb < 0.85-0.85 x > Ti < 0.15-0.15 x > Sn < 0.5 c > Hf < 0.5 d >) O3, a = b = c = d, and x is greater than or equal to 2 and less than or equal to 6; the ceramic is of an ABO3 type perovskite structure, and in the ABO3 type perovskite structure, Bi ions are in a compound occupation form in which the A site and the B site coexist. The preparation method comprises the following steps: (1) proportioning and refining to obtain mixed powder; (2) performing pre-synthesis and powder treatment to obtain uniform powder; (3) preparing a molded green body; (4) removing organic matters; and (5) densifying and sintering to obtain the ferroelectric ceramic. The sodium niobate-based ferroelectric ceramic provided by the invention can achieve the effects of high Wrec, high eta, wide temperature range and excellent stability at the same time.

The invention relates to the technical field of building expansion joint sealing composite materials, in particular to a building expansion joint sealing composite material and a preparation method and application thereof. The preparation method comprises the following steps: mixing an epoxy resin precursor containing disulfide bonds and polyurethane containing disulfide bonds to obtain a polyurethane-epoxy resin matrix with an interpenetrating network structure; a Na source, an Nb source, a Ba source, a Ti source, a Sn source, a Sr source and a Zr source are mixed to prepare the sodium niobate leadless piezoelectric ceramic with piezoelectric performance. The preparation method comprises the following steps: modifying sodium niobate lead-free piezoelectric ceramic by adopting dopamine hydrochloride to obtain polydopamine modified sodium niobate lead-free piezoelectric ceramic; and mixing the polydopamine modified sodium niobate lead-free piezoelectric ceramic, the polyurethane-epoxy resin matrix and the aminated carbon nanotube, and curing to obtain the building expansion joint sealing composite material. The building expansion joint sealing composite material has excellent mechanical properties and bonding strength, has good damping performance in a wide temperature range, and solves the problems in the prior art.

The application discloses a potassium-sodium niobate-based lead-free piezoelectric ceramic material and a preparation method and application thereof, relates to the technical field of functional materials, and has a chemical formula of 0.964K 0.5 Na 0.5 Nb 0.955 Sb 0.045 O3‑0.03Bi 0.5 Na 0.5 ZrO3‑0.006BiFeO3‑xMnO2, wherein x is 0.005-0.04, and x represents a molar fraction. By means of intervention of the oxide sintering aid MnO2, microstructure, compactness, domain structure, phase boundary, loss and defect concentration of the ternary KNN-based piezoelectric ceramic material system are regulated, so that a brand-new potassium-sodium niobate (KNN)-based lead-free piezoelectric ceramic with super-high piezoelectric performance and excellent mechanical performance is obtained.

The invention discloses a flexible piezoelectric micromechanical ultrasonic transducer as well as a preparation method and application thereof. The flexible piezoelectric micromechanical ultrasonic transducer comprises a laminated structure and a flexible coating layer packaging the laminated structure, the laminated structure comprises a flexible substrate, an adhesive layer, a first supporting layer, a second supporting layer, a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially laminated, the first supporting layer is provided with a through cavity structure, and the second supporting layer is provided with a through cavity structure. The first supporting layer and the second supporting layer are both made of epoxy group negative photoresist, and the piezoelectric layer is composed of polyvinylidene fluoride-trifluoroethylene and nano potassium sodium niobate ceramic particles. The flexible piezoelectric micromechanical ultrasonic transducer has the advantages of being high in sensitivity, good in tensile ductility and bendability, capable of flexibly adjusting resonant frequency, easy to array and the like, the preparation method is simple, the production cost is low, batch production is easy, and the flexible piezoelectric micromechanical ultrasonic transducer is suitable for large-scale industrial production and application.

The invention provides a bone repair material as well as a preparation method and application thereof. The bone repair material comprises an oxygen vacancy sodium niobate cerium dioxide heterojunction, the oxygen vacancy sodium niobate cerium dioxide heterojunction comprises the following raw material components in mole number: 3-5 moles of oxygen vacancy sodium niobate; and 1 mole of cerium dioxide. The bone repair material disclosed by the invention has excellent piezoelectric property, sonodynamic property and enzyme-like activity, can promote proliferation and osteogenic differentiation of bone cells and remarkably improve the expression of osteogenic genes, has a remarkable sterilization / biological membrane infection removal effect, and has application potential in the field of infectious bone defects as an antibacterial bone repair material.

The invention discloses a wide temperature stable type medium temperature sintered potassium sodium niobate-based dielectric ceramic material and a preparation method thereof, and relates to the technical field of ceramic preparation, the ceramic material is obtained by co-doping Bi (Li0. 5Nb0. 5) (BLN) and Cu with KNN-based dielectric ceramic, and the molecular formula of the ceramic material is (1-y) K0. 5Na0. 5Nb. CuxO3. YBi (Li0. 5Nb0. 5) O3, 0lt, x is more than or equal to 0.125 and less than or equal to 0.375. The KNN-based dielectric ceramic material which has the advantages of wide temperature range, stability and capability of being sintered at medium temperature is prepared by adopting the method disclosed by the invention. The ceramic material has excellent stability at a wide temperature range while ensuring a relatively high dielectric constant (epsilon 25 DEG C = 2000). The compact ceramic matrix can be obtained through sintering at the temperature of 1060 DEG C, and for the application of a multilayer ceramic capacitor, the cost can be remarkably reduced through low-temperature sintering. The doping of CuO improves the dielectric constant of the ceramic system, inhibits the water absorption of KNN-based ceramic, improves the buckling deformation of a ceramic chip after sintering by adopting buried powder sintering, and improves the process stability.

This invention discloses a polyimide-potassium sodium niobate composite film, its preparation method, and a piezoelectric nanogenerator, belonging to the field of nanogenerator technology. The method includes: ball milling and mixing Nb₂O₅, Na₂CO₃, and K₂CO₃ until uniform and drying; grinding, sieving, calcining, and grinding again to obtain potassium sodium niobate ceramic nanoparticle fillers; mixing anhydrous N,N-dimethylformamide solution and 4,4'-diaminodiphenyl ether powder until uniform; adding pyromellitic dianhydride powder in multiple batches; stirring thoroughly after reaction; adding potassium sodium niobate ceramic nanoparticle fillers; repeated ultrasonication and stirring; heating and stirring reaction; casting; vacuum drying; gradient temperature calcination; and cooling to obtain a polyimide-potassium sodium niobate composite film; the assembled piezoelectric nanogenerator combines... d 31 and d 33 With dual operating modes, it can collect and utilize micro-energy in various application environments, and its power density is significantly enhanced compared to the traditional single operating mode; it also maintains excellent operating stability at a high temperature of 150℃.

The invention discloses sodium niobate-based ceramic for identifying lattice distortion and a preparation method of the sodium niobate-based ceramic, and belongs to the field of inorganic functional ceramic materials. The chemical general formula of the sodium niobate-based ceramic is (1-x) [0.85 (Na0. 94YbaTmb) NbO3-0. 15 (Bi0. 5Na0. 5) TiO3]-x (Ba0. 5Sr0. 5) (Sn0. 5Hf0. 5) O3, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < = alt, 0.01 < 0.02, 0.01 < = blt; 0.02 < = x < = 0.06. The preparation method comprises the following steps: (1) burdening and primarily mixing to obtain primarily mixed powder; (2) pre-sintering the primarily mixed powder, and mixing again to obtain uniform powder; (3) carrying out compression molding on the uniform powder; (4) removing organic matters; and (5) sintering to obtain the sodium niobate-based ceramic. The sodium niobate-based ceramic provided by the invention can realize lossless and high-spatial-resolution distortion detection, and achieves the effect of high sensitivity.

The application relates to a gadolinium-doped high-energy-storage relaxor antiferroelectric sodium niobate-based ceramic material and a preparation method and application thereof. 1‑3x Gd x NbO3; wherein 0.04 < x < 0.12, preferably 0.06 <= x <= 0.10, more preferably 0.08.

The application provides a bismuth-doped sodium niobate / oxygen vacancy ceria heterojunction and a preparation method and application thereof. The bismuth-doped sodium niobate / oxygen vacancy ceria heterojunction comprises the following raw material components in moles: 3-5 moles of bismuth-doped sodium niobate; and 1 mole of oxygen vacancy ceria. The bismuth-doped sodium niobate / oxygen vacancy ceria heterojunction has strong piezoelectric properties and acoustic power properties, and has enzyme-like activity. Under the driving of ultrasonic waves, the piezoelectric effect of the material not only promotes the proliferation of osteoblasts, but also enhances the acoustic power and enzyme-like activity of the material, generates various ROS, cooperatively kills bacteria and removes biofilms, and has potential application prospects in the treatment of infected bone tissues.

The present invention discloses a sodium niobate-based energy storage ceramic material and a preparation method and application thereof, wherein the general formula of the sodium niobate-based energy storage ceramic material is (1-x)(0.85NaNbO3-0.15A 0.1 D 0.85 EG3)‑xAM;A 0.1 D 0.85 EG3 is the general formula of a linear dielectric dissolved in NaNbO3; AM is the general formula of a relaxant capable of improving the relaxation characteristics of the material; wherein A is a Bi element; and the value range of x is 0<x≤0.16. Thus, the obtained NaNbO3-based ceramic can maintain a relatively high polarization characteristic while improving the breakdown field strength, thereby achieving a high energy storage density under medium field strength.

The present invention discloses a potassium sodium niobate-lanthanum bismuthate-sodium niobate-based energy storage ceramic material and a preparation method thereof. The chemical formula of the energy storage ceramic material is (0.9- x )K 0.5 Na 0.5 NbO3‑ x LaBiO3-0.1NaNbO3, where 0.02≤x≤0.045, is prepared according to the general chemical formula, ball-milled, and then granulated with a binder. The ceramic sheet is pressed and formed, and the binder is removed and sintered to obtain an energy storage ceramic material. The present invention adopts the above-mentioned potassium sodium niobate-lanthanum bismuthate-sodium niobate-based energy storage ceramic material and its preparation method. By adding an appropriate amount of lanthanum bismuthate and sodium niobate, the grain refinement of the potassium sodium niobate ceramic is promoted, the density is increased, and a high maximum polarization intensity P is obtained. m , lower residual polarization intensity P r and high breakdown field strength DBS, thereby obtaining excellent energy storage characteristics. In addition, the present invention is simple to operate, has a wide source of raw materials, has low equipment cost, meets environmental protection requirements, and is easy to apply.

This invention discloses a hard sodium potassium niobate lead-free piezoelectric ceramic and its preparation method. The lead-free piezoelectric ceramic is based on sodium potassium niobate ceramic by introducing two metal oxides, CuO and MnO2. The preparation method involves synthesizing sodium potassium niobate ceramic powder, then introducing CuO and MnO2, followed by secondary ball milling, drying and sieving, dry pressing, and sintering. This successfully prepares a hard sodium potassium niobate lead-free piezoelectric ceramic with high piezoelectric constant, low loss, and high mechanical quality factor. d 33 It is 335 pC / N. k p Reaching 0.51, Q m For 363, tan d =0.0103. The introduction of bimetallic cation doping not only ensured sintering quality but also effectively improved [the quality] through defect design. Q m This achieves the effect of hardening ceramics.

The invention discloses a positive electrode material and a preparation method and application thereof. The positive electrode material comprises a positive electrode base material and a coating layer coating the surface of the positive electrode base material; the chemical general formula of the positive electrode base material is AaMexMnyO2, A comprises Na and / or Li, 0.6 < = a < = 1, 0.1 < = x < = 0.4, 0.2 < = y < = 0.6, x + y = 1, and Me comprises a transition metal element; the coating layer comprises sodium niobate. Elements in the positive electrode material are uniformly distributed, and after the positive electrode material is coated with sodium niobate, the effect of isolating the positive electrode material from an electrolyte is achieved, and the dynamic performance and the safety performance of the positive electrode material are also improved.

The invention discloses sintering furnace equipment and a sintering method of a potassium-sodium niobate-based lead-free piezoelectric ceramic piece, and belongs to the technical field of lead-free piezoelectric ceramic preparation. A crucible with a downward opening is arranged in a hearth of the sintering furnace equipment, and a closed space is formed by the crucible and the bottom of the hearth. A sagger with an upward opening is arranged in the closed space, and a clamping device is arranged in the sagger and used for clamping sintering raw materials. According to the sintering furnace equipment, a stable temperature field in the sintering process is kept through the common design of the saggar and the crucible, excessive volatilization of potassium and sodium can be restrained when the potassium-sodium niobate-based leadless piezoelectric ceramic piece is prepared, and the prepared potassium-sodium niobate-based leadless piezoelectric ceramic piece is excellent in performance and good in appearance.