47results about How to "High piezoelectric constant" patented technology

The invention provides solid solution-modified sodium bismuth titanate leadless piezoelectric ceramics and a preparation method thereof. The piezoelectric ceramics are represented by chemical composition general formula of (1-x)(0.74Na0.5Bi0.5TiO3-0.26SrTiO3)-xBa(Zr0.05Ti0.95)O3 or (1-y)(0.9Na0.5Bi0.5TiO3-0.1CaTiO3)-yBa(Zr0.05Ti0.95)O3, wherein 0.04<=x<=0.1 and 0.04<=y<=0.1. Solid solution of Ba(Zr0.05Ti0.95)O3 is realized at the morphotropic phase boundary of a 0.74Na0.5Bi0.5TiO3-0.26SrTiO3 and 0.9Na0.5Bi0.5TiO3-0.1CaTiO3 system, and high-density microcrystalline structure ceramics with uniform crystal grain size distribution are obtained by a two-step forming method and a self-bearing pressure sintering process. The piezoelectric property of the material is optimized by the morphotropic phase boundary composition characteristics and the solid solution modification method, and the piezoelectric constant d33 reaches 110-138 PC / N; the electromechanical coupling coefficient of the material is also increased obviously; the preparation process of the material is simple and stable, and the material is an optimal material for manufacturing low-power ultrasonic devices and energy transducers used in fields of gas sensors, industrial nondestructive test, and the like.

The invention discloses a sodium-potassium niobate-based lead-free piezoelectric ceramic and a preparation method thereof. The chemical formula of the potassium-sodium niobate-based piezoelectric ceramic is (1-x)(K 0.5 Na 0.5 )NbO 3 ‑xBi(Li 0.5 Sb 0.5 )O 3 , where 0.01≤x≤0.20. According to the stoichiometric ratio (1‑x) (K 0.5 Na 0.5 )NbO 3 ‑xBi(Li 0.5 Sb 0.5 )O 3 The weighed and dried raw materials are mixed and then ball-milled and dried to obtain a mixed material; the obtained mixed material in step 1 is pre-burned at a high temperature to obtain a pre-burned powder, and then ball-milled and dried for a second time to obtain a secondary ball-milled powder; Add binder to the powder for granulation, and then sieve and then press and shape to obtain a ceramic blank; remove the organic binder and then sinter at high temperature to obtain a sintered ceramic; the two surfaces of the sintered ceramic are polarized by silver and high pressure , the sodium potassium niobate-based lead-free piezoelectric ceramics were obtained. Through component design and process optimization, the sintering characteristics of sodium potassium niobate-based ceramics are effectively improved, the volatilization of sodium and potassium elements is inhibited, the porosity is reduced, the density of ceramics is improved, and the dielectric constant is increased, the loss is reduced, and the Comprehensive properties of KNN-based ceramics.

The invention discloses a preparation process of high-performance piezoelectric ceramics, which comprises the following steps: 1) taking piezoelectric ceramic raw materials; 2) putting the piezoelectric ceramic raw materials into a ball mill tank to fully mix ball milling, and placing the slurry obtained after ball milling Dry in a drying oven to obtain a powder; 3) Add water to the powder, then add one or any combination of ammonia, citric acid or oxalic acid, and then heat for hydrothermal treatment, the hydrothermally treated powder drying to obtain a piezoelectric ceramic raw material powder; 4) treating the piezoelectric ceramic raw material powder obtained in step 3) with a traditional piezoelectric ceramic treatment process to obtain a high-performance piezoelectric ceramic. The invention has the characteristics of good performance of the prepared piezoelectric ceramics, less raw material consumption, low cost, less pollution, simpler process and good process stability.

The invention discloses a composite high temperature piezoceramic material. The general formula of the component of the ceramic material is represented by Bi3TaTiO9-xBiFeO3, wherein x is the weight percentage of BiFeO3 and Bi3TaTiO9, and x is 20-50 wt%. A preparation process of the material comprises the following steps: respectively synthesizing Bi3TaTiO9 powder and BiFeO3 powder, and carrying out ball milling, mixing and sintering on the Bi3TaTiO9 ceramic powder and the BiFeO3 ceramic powder to obtain ceramic. The piezoelectric constant d33 of the composite high temperature piezoelectric ceramic material d33 reaches 24 pC / N, and is 1.8 times of that of a single-phase Bi3TaTiO9 ceramic material, and the material has a large resistivity rho in a 500 DEG C in high temperature environment, reaching 10<4> omega.m. The composite ceramic material is suitable for making piezoelectric actuators and piezoelectric sensors used in a high temperature environment.

The invention discloses a rare-earth-doped high-Curie-temperature piezoelectric ceramic element. The general chemical formula of the rare-earth-doped high-Curie-temperature piezoelectric ceramic element is: (1‑x‑y)CaBi 2 Ta 2‑a Nb a o 9 +xNa 0.5‑b K b Bi 2.5 Nb 2 o 9 +ySrBi 2 Nb 2‑c Sb c o 9 +zwt%P, where, 0.05≤x≤0.85, 0≤y≤0.1, 0 <a≤0.2，0<b≤0.2，0<c≤0.1，0<z<5，p为coo和mnco3. A combination of one or two sintering aids. The invention also discloses a method for preparing the piezoelectric ceramic element. The piezoelectric ceramic element prepared by the invention has the advantages of high Curie temperature and low aging rate.< / a≤0.2，0<b≤0.2，0<c≤0.1，0<z<5，p为coo和mnco

In a piezoelectric element comprising a first electrode (2) provided on a substrate (1), a piezoelectric material (3) provided on the first electrode (2) and a second electrode (4) provided on the piezoelectric material (3), the piezoelectric material (3) is configured so as to have a perovskite type crystal structure which is represented by a formula ABO3 and in which the main component for the A site is Pb and the main components for the B site are Zr, Ti and Pb, and configured so that a ratio of Pb atoms to all atoms in the B site is more than 3% and not more than 30%. Namely, the piezoelectric material (3) is formed so as to contain Pb excessively and the excess Pb atoms are activated to be Pb<4+> during formation of the piezoelectric material (3) and then introduced into the B site.

The invention discloses a double-end tuning fork scanning probe measurement head system and a measurement method of the double-end tuning fork scanning probe measurement head system. The double-end tuning fork scanning probe measurement head system is composed of a rigidity support, a double-end tuning fork and a tungsten tipped probe. The rigidity support is a rigidity supporting piece of the whole scanning probe measurement head system and is used for fixing a whole measurement head mechanism and forming whole constraint on one fork end of the double-end tuning fork. One fork end of the double-end tuning fork is connected to the bottom face of the rigidity support, the other fork end of the double-end tuning fork serves as a free end, and the tungsten tipped probe with the large draw ratio is fixedly arranged in the middle of the bottom face below the free end. Electrodes are placed according to a periphery partition method and two fork arms of the double-end tuning fork are stimulated to be bent and vibrate in an opposite-phase mode in the thickness direction. The tungsten tipped probe is in contact with a sample in a touched mode in the vertical Z direction and changes of resonance signals of the fork arms are detected to express the touch degree of the tip end of the tungsten tipped probe and the surface of the sample. The double-end tuning fork scanning probe measurement head system can be used for high-resolution and non-destructive measurement on the surfaces of flexible materials and the like and surface appearance scanning on micro-devices such as micro-grooves and micro-steps with large depth-to-width ratios.

The invention discloses a piezoelectric ceramic and a preparation method thereof, a piezoelectric ceramic element and a preparation method thereof. The main chemical formula of the piezoelectric ceramic is: (Na 0.5 Bi 0.5 ) 1‑a‑b+c (Li 0.35 K 0.15 Ho 0.5 ) a (Li 0.35 K 0.15 Er 0.5 ) b Bi 4 Ti 4‑x‑ y V x Mo y o 15 , where 0.05≤a≤0.20, 0.05≤b≤0.20, 0≤c≤0.05, 0≤x≤0.05, 0≤y≤0.05. The preparation method includes: (1) according to the stoichiometric ratio of the metal elements in the general formula of the main components, respectively weigh the corresponding metal oxides or metal salts, mix them, pre-ball mill, dry, and pre-sinter to obtain pre-sintered Piezoelectric ceramic powder; (2) ball milling and drying the pre-sintered piezoelectric ceramic powder, then adding binder, molding, plastic discharge, and sintering to obtain piezoelectric ceramics. The piezoelectric ceramic element prepared by the piezoelectric ceramic has the advantages of high Curie temperature, high piezoelectric constant, excellent piezoelectric performance and high temperature stability, and the like.

The invention discloses a method for growing lead zirconate titanate (PZT) nanorings by using the pulsed laser deposition (PLD) technology. The PLD method is used, and preparation of the PZT nanoringsis realized by precisely controlling the deposition temperature, the annealing temperature, annealing time, the number of laser pulses, oxygen pressure and other parameters. The method can be used for preparing regularly arrayed PZT nanorings, parameter control is simple and convenient, repeatability is high, and no toxic and harmful exhaust gas is emitted. The method provides a possibility for the application of high-density ferroelectric memory devices in the future.