33 results about "Strontium barium niobate" patented technology

The invention relates to a strontium barium niobate based glass-ceramic dielectric material and a preparation method thereof. The preparation method comprises the following steps of: with SrCO3, BaCO3, Nb2O5 and H3BO3 as starting raw materials, proportioning according to the mole ratio of aSrO.bBaO.cNb2O5.dB2O3; carrying out ball milling, mixing the raw materials for 8h, and drying; melting at the temperature of 1300 DEG C, and preserving the heat for 30min; then, rapidly cooling and annealing to obtain astomatous uniform glass; carrying out controllable crystallization at a certain temperature to obtain the glass-ceramic dielectric material. The glass-ceramic dielectric material obtained by using the method has the adjustable relative dielectric constant within the range of 21-143, the highest direct current breakdown field strength of 1300kV/cm and the highest energy density of 5.71J/cm<3>.

In this patent, reaction sintering was used to prepare translucent strontium barium niobate ceramics (SrxBa1-xNb2O6, x=0.2-0.7). High purity powders of strontium carbonate (SrCO3) and barium carbonate (BaCO3) were mixed with niobium oxide (Nb2O5), respectively, at the same mole using ball milling. The mixed powders were dried and ground by a mortar. Thereafter, they were calcined at 800-1050° C. for 1-4 h in air to form strontium niobate (SrNb2O6) and Barium niobate (BaNb2O6), respectively. Precursor powders of strontium niobate (SrNb2O6) and barium niobate (BaNb2O6) were mixed in appropriate ratios and pressed. Compacts were reaction-sintered in a temperature range of 1300 to 1320° C. in O2 and then heat-treated in a temperature range of 1260 to 1275° C. in O2. We also propose the related basic principles and microstructures.

The invention discloses a strontium barium niobate glass ceramic material with high dielectric constant and high breakdown field strength and a preparation method thereof. The preparation method comprises the following steps: uniformly mixing SrCO3, BaCO3, Nb2O5, CaCO3, SiO2, H3BO3 and BaF2, uniformly melting at 1300-1400 DEG C, molding and rapidly annealing to obtain annealed glass; crystalizing the annealed glass at the crystallization temperature and then cooling in a furnace to obtain the strontium barium niobate glass ceramic material. By adopting a melting method to prepare the strontium barium niobate glass ceramic material, the method is simple and convenient, and various molding methods are available. The strontium barium niobate glass ceramic material is treated at first and then is subjected to XRD (X-Ray Diffraction), SEM and EDS tests, and the test results prove that the strontium barium niobate glass ceramic material prepared by the method disclosed by the invention is ferroelectric glass ceramic with high dielectric constant, high breakdown field strength and low dielectric loss.

The invention discloses a material for making electrically-functional strontium barium niobate ceramic by laser and a method thereof. The material consists of barium carbonate, strontium carbonate and titanium dioxide which are compounded according to a molar ratio of (1-x) to x to 1, wherein the x represents a molar mass fraction, and the x is more than 0 or less than 1; the used material is subject to mixture, ball milling, plasticization, granulation, green compaction and evacuation and sintering by CO2 laser, so as to be made into the electrically-functional strontium barium niobate ceramic. The material is low in cost, the laser sintering method consumes less energy, the sintering time is short, and the electrically-functional strontium barium niobate ceramic made by the laser sintering has the advantages of little crystal grain, small porosity, high tightness, high reliability, safety, electricity conservation, etc. In addition, strontium barium niobate is a sosoloid totally combining the barium carbonate and the strontium carbonate, the continuous solid solubility of the strontium barium niobate makes dielectric and optical performances of the ceramic adjusted continuously under the condition that the quantity relative ration between Ba and Sr is in a range of between 0 and 1; meanwhile, the electrically-functional ceramic with a big dielectric coefficient and less dielectric loss can be obtained through adjusting the ration between the Ba and the Sr.

In the method, ferroelectric nonocrystal is distributed uniformly in transparent film polymer as ferroelectric material is made from strontium barium niobate, lead zirconate titanate, lanthanum doped lead zirconate titanate, BaTiO3, LiNbO3, or LiTaO3 with nanocrystal particle diameter of 20-80 nm; polymer base material is made from polymethyl methyl acrylate, polycarbonate, polyimide sort and thermoplastic polyamic acid. The prepare process includes polymerizing ferroelectric nanocrystal in the polymer in polymerization procedure of dissolving nanocrystal and polymer in polar solvent and depositing film by soaking or spinning.

The invention relates to a high-Curie-temperature strontium-barium niobate pyroelectric ceramic material and a preparation method thereof. The material has the composition general formula of SrxBa1-xNb2O6, wherein x is larger than or equal to 0.25 and smaller than or equal to 0.35. The SBN ceramic material high in density and pyroelectric performance is obtained by preparing power through a solid phase method, preparing an SBN blank through cold isostatic pressing forming and other processes, putting the SBN blank in a mold, filling and covering the SBN blank with ZrO2 powder, raising the temperature to 1100-1150 DEG C, linearly and evenly pressurizing to 100-200 MPa with the axis of the mold as the hot-press axis, raising the temperature to 1200-1300 DEG C, keeping the temperature and the pressure for 2-4 h in the air atmosphere, and linearly depressurizing and cooling inside a furnace to the room temperature. The problem that high-Curie-temperature SBN components are poor in pyroelectric performance is solved.

The invention relates to a lanthanum oxide doped strontium-barium niobate based glass ceramic energy storage material and a preparation method thereof. The preparation method includes: blending according to a molar ratio of 20BaCO3-20SrCO3-20Nb2O5-33.5SiO2-5Al2O3-1.5B2O3-xLa2O3; after barreling and mixing, drying, and melting at high temperature; quickly pouring high-temperature melt into a copper die for forming; destressing and annealing at certain temperature, cutting into glass sheets, and performing controlled crystallization to obtain the lanthanum oxide doped strontium-barium niobate based glass ceramic energy storage material. Compared with similar materials, the glass ceramic energy storage material has excellent machining performance, and can be mechanically ground and processed into sheets with thickness lower than 80 um, and convenience is brought to subsequent machining of small devices; the glass ceramic energy storage material has excellent dielectric performance and breakdown field strength resistance.

The invention discloses a method for preparing strontium barium niobate nano-powder through a two-step coprecipitation technology. The method adopts barium oxalate, barium acetate and barium nitrate as raw materials, ammonium carbonate as a precipitant and ammonia water as a pH adjuster. The preparation method comprises the following steps: respectively dissolving the lanthanum oxalate, lanthanumacetate and lanthanum nitrate in deionized water; mixing the obtained lanthanum acetate solution and the obtained lanthanum nitrate solution, adding the ammonium carbonate solution, carrying out fullstirring, and dropwise adding the obtained lanthanum oxalate solution to the above obtained mixed solution; adding the ammonia water to adjust the pH of the solution to 11, and carrying out full stirring; aging the stirred solution, filtering the aged solution, washing the obtained precipitate, and carrying out constant temperature drying on the washed precipitate in a 80 DEG C oven to obtain precursor powder; and calcining the powder to obtain the strontium barium niobate nano-powder. The method for preparing the strontium barium niobate nano-powder has the advantages of no toxic, highly-corrosive and expensive chemical reagents, simple device, compact process and low preparation cost, and the obtained nano-powder can be used to prepare strontium barium niobate ceramic having an electrocaloric effect.

The invention discloses a photo refraction double-doped potassium sodium strontium barium niobate single crystal. Two kinds of metal oxide are doped into (KNa)0.1(Sr0.65Ba0.35)0.9Nb2O6 crystals, one kind is Cr2O3 or Ni2O3, and the other kind is Cr2O3; when the metal oxide is a combination of Cr2O3 and Gr2O3, the content of Cr2O3 is 0.2-0.5 mol%%, and the content of Gr2O3 is 1-1.8 mol%; when the metal oxide is a combination of Ni2O3 and Gr2O3, the content of Ni2O3 is 0.1-0.4 mol%, and the content of Gr2O3 is 1-1.6 mol%. The product has the advantages of being high in sensitivity to weak light, high in optical damage resistance and high in record response speed in photo refraction application. The invention further discloses a preparation method of the photo refraction double-doped potassium sodium strontium barium niobate single crystal. The preparation method comprises the procedures of raw material preparation, ball milling, heating, stirring and reacting, temperature rise lifting and drawing, high temperature annealing, polarization and the like, and has the advantages of being simple in process step, good in finished product quality and low in energy consumption.

The invention provides a barium strontium niobate/boron nitride three-dimensional network material and a preparation method thereof. According to the method, dry luffa is used as a template, and a three-dimensional network barium strontium niobate/boron nitride filler is prepared by adopting a sacrificial template method; barium strontium niobate/boron nitride nano-powder, polyvinyl alcohol, carboxymethyl cellulose and polyacrylamide are used as raw materials for preparation of slurry with good thixotropic properties; the dry luffa is treated by a NaOH solution so as to regulate and control the pore diameter and the communication mode of the dry luffa; then treated dry luffa is soaked into the slurry, then squeezed to remove redundant slurry, and finally dried; and the steps of slurry hanging and drying are repeated a plurality of times, and then heat treatment is performed to obtain the barium strontium niobate/boron nitride filler with a three-dimensional network structure. The barium strontium niobate/boron nitride filler with the three-dimensional network structure can realize effective linking among the filler under the condition of low volume fraction filling, so the interaction among the filler is improved, and the dielectric property of the material is enhanced.

The invention discloses a strontium barium sodium niobate tungsten bronze type piezoelectric ceramic material with low sintering temperature and anisotropy and a preparation method thereof. The structural general formula of the ceramic material is Sr1.4Ba0.6NaNb5O15+xwt.%M, M is CuO or MnO2, and the value of x is 0.25-1.0. According to the invention, Sr1.4Ba0.6NaNb5O15 is modified by doping Cu and Mn, so that the sintering temperature of ceramic is greatly reduced, the energy consumption of the ceramic in the sintering process is reduced, and the ceramic is energy-saving and environment-friendly; and meanwhile, the anisotropy of the modified ceramic is obviously reduced after Cu and Mn are doped, the density is obviously improved, the electrical property is further improved, and the obtained ceramic material has a relatively high dielectric constant and relatively low dielectric loss, and in addition, the ceramic material has a relatively good ferroelectric property. The ceramic material disclosed by the invention is simple in preparation method, low in cost, good in repeatability and high in yield, and is expected to provide powerful reference for modification research of the lead-free niobate material with the oriented growth tungsten bronze structure.

The invention relates to a strontium barium potassium niobate-based glass ceramic energy storage material, and a preparation method and application thereof. The preparation method specifically comprises the following steps: proportioning raw materials comprising SrCO3, BaCO3, K2CO3, Nb2O5 and SiO2 according to the molar ratio of 25.6mol%[xSrCO3+(1-x)BaCO3]-6.4mol%K2CO3-32mol%Nb2O5-36mol%SiO2, wherein the value range of x is from 0.2 to 1; ball-milling and mixing the materials, drying and melting at high temperature to obtain a high-temperature melt; and pouring the high-temperature melt into a preheated metal mould, performing stress-relief annealing to prepare transparent glass, and cutting the transparent glass into glass sheets; performing controlled crystallization on the glass sheets to obtain the strontium barium potassium niobate-based glass ceramic energy storage material. The strontium barium potassium niobate-based glass ceramic energy storage material is applied to energy storage capacitor materials. Compared with the prior art, the strontium barium potassium niobate-based glass ceramic energy storage material has the advantages that the glass ceramic energy storage material prepared by adding strontium in a barium potassium niobate system has high energy storage density (17.28 J/cm<3>), a uniform and compact microstructure and low tangent value (0.006) of a dielectric loss angle.

The invention provides glass ceramics with a high dielectric constant. The glass ceramics comprises is prepared from the following ingredientscomponents in parts by weight: 15-30 wt% of SiO2, 10-18 wt% of SrO, 15-35 wt% of BaO, 20-35 wt% of Nb2O5, 0.5-10 wt% of Na2O and 1-5 wt% of ZrO2. The relative dielectric constant of the glass ceramics provided disclosed by the invention is above 40 or more,and the glass ceramics has a high relative dielectric constant and can be used for dielectric film substrates, protective glass, disk substrates and the like in a filter. Each component and contents are optimized, so that the problem of the forming opacificationand film formation of the glass ceramics which takes quartz solid solution and strontium barium niobate as main crystal phases can be solved, in addition, internal quality is even, and the glass ceramics can be efficiently and stably produced.

The invention discloses a method for preparing and using laser crystal mixed with the barium strontium niobium oxide, which relate to the field of the intraocular lens. At a temperature of about 1700 DEG C, the invention, at a crystal rotation speed of 5 to 20 rotations per minute and a pulling rate of 0.5 to 2mm per hour, grows the crystal of Nd<3+>:(Ba0.5Sr0.5)5Nb4O15 of high quality and larger dimension through a czochralski method. The crystal belongs to the P3m1 space group, and has a refractive index of 2.0. The crystal is a novel laser crystal, which can generate a laser output with a wavelength of about 1.06 or 0.9 Mum. A solid laser made from the crystal can be applied in the fields such as spectroscopy, biomedicine, military science and etc.

The invention discloses an epitaxial niobium acid strontium barium film with a transparent and conductive nickel acid lithium bottom electrode and the preparing method. One face of an MgO base plate is epitaxially aggraded with a LNO nickel acid lithium transparent and conductive layer LNO film, and a SBN film is epitaxially prepared on the LNO film. The preparing steps are as follows: firstly, lithium carbonate, nickel oxide, niobium oxide, strontium carbonate and barium carbonate are served as materials, and lithium carbonate target material and niobium acid strontium barium target material are respectively prepared using a solid state sintered method. Secondly, the (001) MgO base plate is placed in a reacting chamber after being cleaned. The reacting chamber is pumped into vacuum and the base plated is heated. Oxygen is served as protective gas, and is guided into the reacting chamber. The target material is spattered by impulse laser, and nickel acid lithium conductive electrode and niobium acid strontium barium film are orderly and epitaxially aggraded on the base plate. The preparing method of the invention is simple. The prepared niobium acid strontium barium film (001) directionally and epitaxially grows. The epitaxial performance and the quality of the film are good, and the electro-optical coefficient is large (r33 can reach 180 pm/V to 230 pm/V). Thereby the invention has excellent applied foreground.

The invention relates to a ywt%M-SrxBa1-xNb2O6 series photo-catalyst normal-temperature degradation non-methane hydrocarbon (NMHC) technology. The catalyst is shown as a general formula: ywt%M-SrxBa1-xNb2O6, wherein M is one of Pt, Ag, Au, Pd, Ru, Fe, Co, Ni and Cu; x is greater than or equal to 0.4 and less than or equal to 0.8; y is greater than or equal to 0 and less than or equal to 4. The ywt%M-SrxBa1-xNb2O6 series photo-catalyst has the advantages of low cost, high photo-catalytic activity and high stability, and NMHC gas can be subjected to efficient photo-catalytic degradation at a normal temperature by simulation of sunlight radiation. Meanwhile, the photo-catalyst is very easy to recycle, and has a very good application prospect in removal of NMHC gas from atmospheric air at the normal temperature and a normal pressure and under a mild condition.