31 results about "Niobium pentaoxide" patented technology

The invention relates to the technical field of ceramic glaze production, in particular to interlayer chemical coupling long-acting noctilucent ceramic glaze as well as a preparation method and application thereof. The glaze is of a multi-layer composite structure and sequentially comprises a bottom-layer combined glaze layer, a core noctilucent functional glaze layer and a photochromic protective cover glaze layer from inside to outside. The core layer adopts a glaze system containing niobium pentoxide to realize chemical coupling with the bottom layer, and adopts a core-shell structure long afterglow luminescent material to realize white light adjustability; and the protective cover glaze layer adopts a WO3 / TiO2 / CeO2 composite system. The glaze is prepared through a two-step method of high-temperature primary firing and low-temperature secondary firing, and the obtained glaze is high in interlayer bonding strength, high in weather resistance, long in luminous life, capable of adapting to ambient light and suitable for safety sign products in extreme environments.

The invention provides a method for preparing a high-purity niobium ingot by utilizing multistage refining and the high-purity niobium ingot, and the method comprises the following steps: (1) taking aluminum particles, niobium pentoxide, a heat generating agent and a slag former as raw materials, preparing an aluminum-niobium alloy ingot by adopting an exothermic method outside a furnace, and then carrying out surface treatment and crushing treatment to obtain aluminum-niobium alloy particles; (2) the aluminum-niobium alloy particles are subjected to horizontal electron beam smelting, and a smelted niobium plate is obtained; (3) stacking a plurality of smelting niobium plates, and then sequentially performing vacuum diffusion welding and vacuum arc smelting to obtain a primary niobium ingot; and (4) the primary niobium ingot is placed in a double-gun electron beam smelting furnace to be smelted, and the high-purity niobium ingot is obtained. The stable production of the high-RRR value high-purity niobium is realized by adopting a multi-stage refining process coupling system of an aluminothermy method, horizontal electron beam melting, diffusion welding, electric arc melting and double-gun electron beam melting, and the technical problems of high energy consumption, high cost, low production efficiency and the like in the traditional process are effectively solved.

The application relates to a high-capacity porous niobium pentoxide material and a preparation method and application thereof, relates to niobium pentoxide and preparation and application thereof, and aims to solve the technical problems of low conductivity and slow ion diffusion of existing orthogonal phase niobium pentoxide materials. The material is formed by interconnection of 100-300 nm niobium pentoxide matrix nanoparticles, growth of 10-30 nm secondary nanoparticles on the surface, and a 'raspberry-like' multi-level assembly morphology; the material has a pore diameter of 2-20 nm, a specific surface area of 15-45 m 2 / g; and has an orthogonal phase niobium pentoxide structure and carbon doping characteristics. The material is prepared by using a surfactant containing a quaternary ammonium cation as a soft template, utilizing electrostatic-coordination synergistic action to drive niobium salt and organic quaternary ammonium cation assembly, and high-temperature sintering in an inert atmosphere. When used as a negative electrode of a lithium ion battery, the material reaches a capacity of 350 mAh / g at a current density of 0.1 A / g, and can be used in the field of fast-charging type alkali metal ion batteries.

The application discloses a ceramic filler composition suitable for a silicone rubber foam material and application thereof. The ceramic filler composition comprises nano magnesium-aluminum hydrotalcite, ceramic auxiliary filler and ceramic filler, and the mass ratio of the three is 1-5:13-35:3-12. The ceramic auxiliary filler comprises low-melting point glass powder, lithium carbonate and di-niobium pentoxide, and the mass ratio of the three is 6-20:2-7:3-8. The melting point of the low-melting point glass powder is 320-650 DEG C. The ceramic filler comprises one or more of titanium dioxide, mica powder, wollastonite, montmorillonite, diatomite and kaolin.

The invention provides a high-voltage ceramic capacitor and a manufacturing method thereof, and relates to the technical field of electronic materials, the high-voltage ceramic capacitor comprises a ceramic dielectric layer and an electrode layer, the ceramic dielectric layer is prepared from the following raw materials in percentage by weight: 85% of barium titanate (BaT iO3), 10% of barium zirconate (BaZrO3), 3% of yttrium oxide (Y2O3) and 2% of niobium pentoxide (Nb2O5), by optimizing the formula and the preparation process of the ceramic dielectric layer, the dielectric constant of the high-voltage ceramic capacitor is remarkably improved, the high-voltage ceramic capacitor has excellent voltage resistance, reliable operation of equipment under a high-voltage condition is ensured, the risk of faults caused by voltage fluctuation is reduced, and the service life of the high-voltage ceramic capacitor is prolonged. In addition, the multi-layer metallized electrode structure effectively improves the mechanical properties of the electrode and the ceramic dielectric layer, improves the tensile strength of the electrode and the pin part, and improves the overall reliability of the capacitor.

The invention belongs to the technical field of ceramics, and discloses a special ceramic based on modified aluminum ash and a preparation method thereof. The special ceramic comprises the following raw material components in parts by weight: 1-10 parts of modified aluminum ash; 30 to 60 parts of clay; 10 to 20 parts of fly ash; 1 to 10 parts of niobium pentoxide; 1 to 5 parts of albite; 5 to 15 parts of barite; 2-8 parts of a metal oxide; 1-5 parts of carbide; 3 to 10 parts of nitride; 1-5 parts of polyvinyl alcohol; wherein the modified raw materials of the modified aluminum ash comprise a silane coupling agent, acrylate and bisphenol A novolac epoxy resin containing double bonds. The invention provides a reliable scheme for efficient utilization of the secondary aluminum ash and green and high-performance development of special ceramics. The special ceramic has high hardness, high bending strength and corrosion resistance at the same time, the Vickers hardness is 92-95 GPa, the bending strength is 974-991 MPa, and the corrosion depth is 0.20-0.32 mm.

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 belongs to the technical field of ceramic lining plate preparation, and particularly relates to a wear-resistant ceramic lining plate and a preparation method thereof. The wear-resistant ceramic lining plate is prepared from the following raw materials: aluminum oxide, a sintering aid, aluminum titanate, modified urea resin microspheres, hafnium boride, tungsten disilicide and a KH-550 silane coupling agent, and the sintering aid is a mixture of niobium pentoxide, strontium oxide, lanthanum oxide and magnesium oxide. According to the wear-resistant ceramic lining plate, aluminum oxide serves as a main raw material, a mixture of niobium pentoxide, strontium oxide, lanthanum oxide and magnesium oxide serves as a sintering aid, a compound of modified urea-formaldehyde resin microspheres, hafnium boride and tungsten disilicide serves as a reinforcing and toughening phase, aluminum titanate serves as a conditioning agent, and the raw materials have a synergistic effect; and it is ensured that the prepared ceramic lining plate has good wear resistance, hardness and toughness.

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium battery modified graphite negative electrode material, a preparation method thereof and a lithium battery, and the preparation method comprises the following steps: slowly adding water into an alcohol dispersion liquid of niobium pentoxide, stirring, and preheating for a set time to obtain a niobium pentoxide mixed solution; mixing the porous graphite precursor with the niobium pentoxide mixed solution, heating and stirring to volatilize the solvent to obtain solid powder; and carrying out heat treatment on the solid powder in an inert atmosphere at the temperature of 700-900 DEG C for 2-3 hours, thereby obtaining the product. A three-dimensional interconnected porous network is constructed in graphite particles, and a coating layer is constructed on the surface of graphite, so that an internal and external synergistic effect is realized, the wettability of graphite to an electrolyte is remarkably improved, and meanwhile, the fast charging capacity of a battery is improved.

The invention discloses an antioxidant waste magnesium alloy-aqueous solution hydrogen production system and a preparation method thereof, and belongs to the technical field of recycling of hydrogen production materials and waste magnesium alloys. The preparation method comprises the following steps: step 1, putting niobium pentoxide and cerium dioxide into a ball milling tank, and respectively carrying out continuous long-time low-energy ball milling and short-time high-energy ball milling; step 2, calcining the mixed powder to prepare a CeNb2O7 material; step 3, after the waste magnesium alloy is mechanically crushed, performing high-energy ball milling on the crushed waste magnesium alloy and a CeNb2O7 material to prepare waste magnesium alloy-CeNb2O7 composite hydrogen production particles, and performing tabletting and forming on the waste magnesium alloy-CeNb2O7 composite hydrogen production particles; and 4, preparing an aqueous solution, namely dissolving ethylene diamine tetraacetic acid, sodium hexametaphosphate and sodium chloride in water to form the aqueous solution. The preparation process is simple, the cost is low, efficient utilization of the waste magnesium alloy is achieved, and the prepared composite hydrogen production material can be stably stored and transported, can quickly respond to hydrolysis hydrogen production and is suitable for industrial production.

The application relates to a wide-temperature-range negative temperature coefficient thermosensitive ceramic material and a preparation method thereof. The thermosensitive ceramic material comprises, in percentage by weight, 58.17-71.47% of lanthanum trioxide, 20.53-23.01% of aluminum trioxide, 3.98-15.36% of cerium dioxide and 1.54-5.94% of niobium pentoxide, and the chemical composition is La 1‑ x Ce x Al 1‑y Nb y O3, wherein x=0.05-0.20 and y=0.025-0.10. The NTC thermistor has the advantages of an ultra-wide temperature range (25 DEG C-1500 DEG C), good consistency of resistance value and B value, a resistance drift rate of less than 0.375% after aging for 500 hours at high temperature, high stability, long service life and the like.

The invention provides a preparation method of a hole sealing coating for a plasma spraying thermal barrier coating, and relates to the technical field of high-temperature thermal insulation materials. The hole sealing coating comprises the following raw materials in parts by weight: 40-50 parts of ammonia water (with the concentration of 25%), 30-50 parts of enamel powder, 30-50 parts of functional powder, 20-30 parts of zirconium oxychloride, 20-30 parts of yttrium chloride, 5-10 parts of ytterbium nitrate, 5-10 parts of gadolinium nitrate, 5-10 parts of dysprosium nitrate, 5-10 parts of chromic nitrate, 5-10 parts of tantalum pentoxide, 5-10 parts of niobium pentoxide, 3-5 parts of titanium dioxide, 3-5 parts of silicon dioxide, 3-5 parts of a binder, 60-90 parts of absolute ethyl alcohol and 40-60 parts of a solvent. The nano ceramic powder is prepared by using a hydrothermal reaction method, then the enamel powder, the nano ceramic powder and the like are mixed, wet grinding, drying, tabletting and calcining are performed to prepare a ceramic block which is applied to film plating, and the hole sealing coating is high in density and bonding strength, and can slow down the transmittance of oxygen, improve the oxidation resistance, improve the radiation coefficient of the coating and prolong the service life.

The application discloses a preparation method and application of a carbon fluoride / niobium pentoxide mixed positive electrode. The niobium pentoxide and a carbon precursor are mixed and ball milled according to a certain proportion, and then a gas phase fluorination is carried out on the mixture to prepare a carbon fluoride / niobium pentoxide composite material. The carbon fluoride / niobium pentoxide positive electrode is prepared by using a homogenate coating method, and the positive electrode is used in a lithium / carbon fluoride primary battery.

The application discloses a low-melting-point 18K gold material and a manufacturing process and application thereof, belongs to the technical field of alloy materials, and aims at solving the technical problem that the mechanical strength of an alloy is reduced while the melting point is reduced in the prior art; the low-melting-point 18K gold material is composed of the following components: Au 75.0%, Ag 8.0%-12.0%, Cu 4.5%-6.5%, Ge 2.0%-3.0%, Pd 1.5%-3.0%, Zn 2.0%-4.0%, Si 0.1%-0.5%, C 0.1%-0.3%, and inevitable impurities with a total amount of not more than 0.2%. In the smelting process, the application adds niobium pentoxide, which can oxidize carbon monoxide into carbon dioxide in the gold melt during the smelting process, reduces the emission of carbon monoxide, and makes the smelting process more environmentally friendly.

This invention belongs to the field of ceramic liner preparation technology, specifically relating to a wear-resistant ceramic liner and its preparation method. The wear-resistant ceramic liner is composed of the following raw materials: alumina, sintering aid, aluminum titanate, modified urea-formaldehyde resin microspheres, hafnium boride, tungsten disilicide, and KH-550 silane coupling agent. The sintering aid is a mixture of niobium pentoxide, strontium oxide, lanthanum oxide, and magnesium oxide. The wear-resistant ceramic liner of this invention uses alumina as the main raw material, a mixture of niobium pentoxide, strontium oxide, lanthanum oxide, and magnesium oxide as the sintering aid, a composite of modified urea-formaldehyde resin microspheres, hafnium boride, and tungsten disilicide as the reinforcing and toughening phase, and aluminum titanate as a modifier. The synergistic effect of the raw materials ensures that the prepared ceramic liner has good wear resistance, hardness, and toughness.

This invention discloses a sulfur-loaded, nitrogen-sulfur co-doped niobium pentoxide-modified porous carbon composite electrode material and its preparation method, as well as a lithium-sulfur battery, belonging to the technical field of lithium-sulfur battery cathode material preparation. The method includes: activating a biomass carbon precursor with potassium hydroxide and carbonizing it at high temperature to obtain porous carbon; reacting a niobium source with the porous carbon in ethylene glycol via solvothermal reaction to obtain amorphous niobium pentoxide-modified porous carbon, followed by calcination to obtain orthorhombic niobium pentoxide-modified porous carbon; mixing with thiourea and heat-treating to obtain the nitrogen-sulfur co-doped niobium pentoxide-modified porous carbon composite electrode material; and then mixing with elemental sulfur and heat-treating to obtain a sulfur-loaded electrode material. This invention utilizes nitrogen-sulfur co-doping to regulate the electronic structure of niobium pentoxide, enhancing its chemical adsorption and catalytic conversion capabilities for lithium polysulfides. Combined with the high conductivity and structural buffering effect of porous carbon, it synergistically suppresses the shuttle effect, improving cycle stability and rate performance. This method is process-controllable, uses widely available raw materials, and is suitable for large-scale production.

The present application relates to the technical field of ceramic glaze production, in particular to long-acting luminescent ceramic glaze with interlayer chemical coupling and its preparation method and application. The glaze is a multilayer composite structure, which comprises a bottom bonding glaze layer, a core luminescent functional glaze layer and a photochromic protective surface glaze layer from inside to outside. The core layer uses an Nb2O5-containing glaze system to realize chemical coupling with the bottom layer, and uses a core-shell structure long afterglow luminescent material to realize white light adjustment; the protective surface glaze layer adopts a WO3 / TiO2 / CeO2 composite system. The present application is prepared by a two-step method of "high-temperature one-time firing + low-temperature secondary firing", and the obtained glaze has high interlayer bonding strength, strong weather resistance, long luminescent life and can adapt to environmental light, and is suitable for safety marking products in extreme environments.

The invention discloses a lead-acid storage battery based on a composite electrolyte and a preparation method of the lead-acid storage battery, particularly relates to the technical field of materials, and relates to the lead-acid storage battery based on the composite electrolyte and the preparation method of the lead-acid storage battery. The lead-acid storage battery based on the composite electrolyte is prepared from vinyl imidazole, 1, 3-propane sultone, azodiisobutyronitrile, concentrated sulfuric acid, nano silicon dioxide and niobium pentoxide. According to the invention, a large amount of corrosive hydrogen ions and sulfate ions are anchored on a stable polymer-inorganic framework in situ by utilizing strong interaction between sulfonic acid groups on an acidic ionic liquid polymer chain and the surface of the nano metal oxide, so that the concentration of free and transferable strong corrosive components in the electrolyte is greatly reduced; and the electrochemical corrosion power of the electrolyte is weakened.

This invention belongs to the technical field of electrical inorganic materials, specifically relating to a high-whiteness, high-voltage resistant insulator ceramic material and its preparation process. The ceramic material, by mass, consists of a basic component, a structure-regulating component, and an auxiliary phase component. Zirconia and niobium pentoxide are introduced to construct a composite regulation system, and various components such as talc, barium oxide, and magnesium oxide are combined to form a multiphase compatibility structure. The auxiliary phase uses rare earth oxides and borate fluxes to adjust the phase composition and stability. The preparation method includes steps such as raw material mixing, pressure filtration and mud refining, molding, drying and bisque firing, glazing, and high-temperature firing. A composite oxide glaze system is used for glaze construction. This invention features strong formulation synergy and precise structure regulation in its material composition and sintering process, making it suitable for the preparation of high-performance insulator ceramic products.

The application provides a method for preparing high-purity niobium ingot by using multi-stage refining and high-purity niobium ingot, and the method comprises the following steps: (1) taking aluminum particles, niobium pentoxide, a heating agent and a slagging agent as raw materials, preparing aluminum-niobium alloy ingot by using an off-furnace aluminothermic method, then performing surface treatment and crushing treatment to obtain aluminum-niobium alloy particles; (2) performing horizontal electron beam melting on the aluminum-niobium alloy particles to obtain molten niobium plates; (3) stacking a plurality of molten niobium plates, then sequentially performing vacuum diffusion welding and vacuum arc melting to obtain a primary niobium ingot; and (4) placing the primary niobium ingot in a double-gun electron beam melting furnace for melting treatment to obtain the high-purity niobium ingot. The multi-stage refining process coupling system of "aluminothermic method→horizontal electron beam melting→diffusion welding→arc melting→double-gun electron beam melting" is adopted to realize the stable production of high-purity niobium with high RRR value, and effectively solves the technical problems of high energy consumption, high cost and low production efficiency existing in the traditional process.

This invention relates to the field of humidity-sensitive materials technology, specifically to a ceramic-based high-sensitivity humidity-sensitive material and its preparation method, addressing the problems of low humidity sensitivity and slow response time in existing humidity-sensitive materials. Using niobium pentoxide and titanium as raw materials, core-shell powder is prepared via a two-step hydrothermal method, followed by electrochemical cathodic polarization to induce high oxygen vacancy concentration in the shell layer and optimize the heterojunction interface state. The material is prepared using a sol-gel method combined with high-temperature solid-state reaction, and processed via Li… + With Al 3+ Ti in the TiO2 lattice 4+ The dual acceptor cooperative substitution induces the generation of high-density oxygen vacancies and introduces Li + An ion-conducting channel is formed by spraying an aerosol deposition film and then annealing it under nitrogen protection to obtain a moisture-sensitive material. This moisture-sensitive material has a low response time, low hysteresis, and excellent long-term stability. Through the synergistic effect of the core-shell heterojunction barrier amplification effect and dual acceptor defect engineering, the sensitivity and response speed of the ceramic-based moisture-sensitive material are significantly improved.

The invention provides a high-performance high-voltage ceramic capacitor and a manufacturing process thereof, and relates to the technical field of electronic materials, and the capacitor comprises a ceramic dielectric layer and an electrode layer with an innovative structure. The ceramic dielectric layer is composed of barium titanate, barium zirconate, yttrium oxide and niobium pentoxide with specific purity and particle size distribution, and a nanoscale additive is introduced. The electrode layer realizes hierarchical alternate deposition of copper and nickel chromium at the scale of 10nm through magnetron sputtering, and is of a multi-layer gradient structure. The manufacturing process is accurately controlled and comprises the links of batching, ball-milling mixing, ultrasonic dispersion, forming, sintering, pulse annealing, performance testing and the like. By optimizing the materials and the process, the dielectric property, the voltage resistance, the conductivity and the corrosion resistance of the capacitor are remarkably improved, and the stable and consistent product quality is ensured. The performance test system is strict and comprehensive, can meet the strict requirements of modern electronic equipment, and has a wide application prospect in the field of electronics.

The invention belongs to the technical field of battery materials, and particularly relates to a negative electrode active material, a preparation method and a lithium ion battery. The method comprises the following steps: reacting niobium pentachloride in an alkaline environment to obtain niobium hydroxide; niobium hydroxide is calcined at the temperature of 600 DEG C to 850 DEG C, and niobium pentoxide is obtained; niobium pentoxide and metal oxide are mixed and then calcined at 900-1100 DEG C to obtain the negative active material, and / or the niobium pentoxide and metal oxide mixed and calcined material is further mixed with solid electrolyte through solid phase and then calcined at 650-750 DEG C to obtain the negative active material. The invention provides a method capable of producing niobium pentoxide and a negative electrode active material in a large scale, and the method can be applied to a battery to realize high safety, long circulation and ultrafast charge of the lithium battery.

The invention provides a process for macroscopically preparing a high-performance CO2 adsorbent NbOFFIVE-1-Ni and forming the high-performance CO2 adsorbent NbOFFIVE-1-Ni, which comprises the following steps: mixing niobium pentoxide, pyrazine, nickel nitrate hexahydrate, hydrofluoric acid and deionized water in a polytetrafluoroethylene container, and carrying out hydrothermal reaction at 120-140 DEG C to obtain blue powder NbOFFIVE-1-Ni; the preparation method comprises the following steps: mixing blue powder with an ethanol solution of polyvinyl butyral (PVB) in a certain mass ratio, segmenting the mixture by virtue of an extrusion molding method, and then drying, so as to obtain the molded strip-shaped particle NbOFFIVE-1-Ni-PVB. According to the method, kilogram-level preparation of NbOFFIVE-1-Ni is realized by regulating and controlling the concentration of the raw materials and reaction conditions, and the adsorption performance of the NbOFFIVE-1-Ni is not reduced; and then the NbOFFIVE-1-Ni is mixed with a high polymer material PVB, so that the compressive strength is improved by one order of magnitude on the premise that the adsorption capacity is not lost, and the problems that NbOFFIVE-1-Ni is low in compressive strength and difficult to prepare on a large scale are solved.

The application discloses a kind of green ceramic glaze and its application, belong to ceramic technical field.Green pigment and ceramic glaze are included, the ceramic glaze includes the following components according to mass fraction: waste ceramic powder 10~15 parts, Longyan kaolin 11~17 parts, nepheline syenite 9~14 parts, calcite 14~16 parts, magnesium oxide 6~8 parts, bauxite 12~18 parts, ammonium hexafluorozirconate 9~13 parts, mica stone 12~14 parts, and niobium pentoxide 6~9 parts.Green ceramic product is prepared for testing, and all pass low concentration acid and alkali test, and in thermal shock resistance test, 180 DEG C to 20 DEG C heat exchange once does not crack.Not only that, but also high gloss green glaze, and the bending strength is all higher than 55.3MPa.

The application relates to a preparation method of an aluminum niobium intermediate alloy for titanium alloy smelting, which comprises the following steps: 1) raw materials including main raw material niobium pentoxide, reducing agent metal aluminum powder, slag forming agent calcium oxide and calcium fluoride, and the above raw materials are mixed and pretreated; 2) the mixture of step 1) is put into a reaction device, and a heat supplement agent is added; 3) the material is ignited to make the material have an aluminothermic combustion reaction; 4) after the reaction is finished, the material is slowly cooled in the original position, and then is naturally cooled to room temperature; and 5) after the cooling is finished, the slag and the gold are separated, and the aluminum niobium intermediate alloy is obtained. The application considers the product quality, low cost, practicability and industrial popularization, and finally prepares AlNb intermediate alloy grades of AlNb50, AlNb60 and AlNb70, and the product quality meets the use requirements of titanium alloy smelting.

This invention relates to the field of microwave dielectric materials technology, and provides a niobium pentoxide-doped zinc borosilicate microcrystalline glass and its preparation method. This invention reduces the melting and volatilization of boron oxide and the formation of zinc borate by designing a low-boron zinc borosilicate microcrystalline glass formulation; and by introducing niobium pentoxide, utilizing Nb... 5+ The high electric field strength disrupts the original structural units in the glass structure, reconstructs the glass network structure, and thus modulates the dielectric properties of the glass-ceramic. Furthermore, the introduction of niobium pentoxide can regulate the glass crystallization characteristics, resulting in a glass-ceramic with a lower sintering temperature and better density. The results of the embodiments show that the dielectric constant of the niobium pentoxide-doped zinc borosilicate glass-ceramic obtained by sintering at 925℃ for 30 min is in the range of 4.4–6.1, and the dielectric loss is in the range of (0.48–5.36) × 10⁻⁶. ‑3 (between 1MHz)

The invention provides a preparation method for synthesizing niobium carbide by a one-step method, and relates to the technical field of preparation of refractory high-temperature materials, and the preparation method comprises the following steps: (1) raw material pretreatment: (a) mixing niobium pentoxide and a complex acid solution, stirring, filtering, drying, crushing and sieving, and taking a screen underflow to obtain niobium-containing precursor powder; (b) mixing the niobium-containing precursor powder with conductive carbon black, then carrying out ball-milling activation, and sieving to take screen underflow, so as to obtain raw material powder; and (2) one-step carbonization reduction: carrying out a heat preservation reaction on the raw material powder under a vacuum condition at the temperature of 1300-1400 DEG C, and cooling to obtain the niobium carbide. The method solves the technical problems of high temperature, high energy consumption, poor product purity, coarse and uneven granularity and complex process in the traditional process, and realizes high purity, ultrafine granularity and low impurity content when the niobium carbide is synthesized by a low-temperature one-step method under the kilogram-level mass production scale.

The invention relates to the field of piezoelectric materials, and discloses a bismuth calcium niobate textured ceramic and a preparation method thereof.The bismuth calcium niobate textured ceramic is prepared by sintering a cast film prepared from ceramic slurry, the ceramic slurry comprises a base material, a solvent, a template agent and a film forming system, and the base material comprises calcium carbonate, bismuth oxide and niobium pentoxide; the film forming system comprises glyceryl trioleate, di-n-octyl phthalate and polyvinyl butyral; cracks of a cast film prepared from the ceramic slurry are remarkably reduced, microdefects of the prepared ceramic are remarkably reduced, and the piezoelectric constant of the bismuth calcium niobate textured ceramic is remarkably improved and can reach 35.8-36.8 pC / N; in addition, the upper limit of the knife height of one-time casting of the ceramic slurry is remarkably improved, the thickness of a green film is remarkably improved, the stacking frequency of a cast film is remarkably reduced, and the processing efficiency is remarkably improved.

The invention belongs to the technical field of refractory materials. The invention provides a high-strength refractory ceramic material and a preparation method thereof.The high-strength refractory ceramic material is prepared from, by weight, 43-45 parts of aluminum oxide, 43-45 parts of titanium oxide, 10.7-11.2 parts of mullite, 1.5-1.8 parts of niobium pentoxide and 2.2-2.5 parts of cobalt-doped silicon dioxide; wherein the mass ratio of aluminum oxide to titanium oxide is 1: 1. According to the invention, the use amount / content ratio of mullite is reduced, so that the breaking strength of the ceramic material is improved while the thermal expansion coefficient of the prepared ceramic material is ensured to be lower.