Patent classifications
C04B35/62695
Sandwich-structured dielectric materials for pulse energy storage as well as preparation method and application thereof
A sandwich-structured dielectric material for pulse energy storage is provided as well as a preparation method thereof. Employing a sandwich structure and combining the properties of ceramic-glass materials prepares a high performance dielectric material for pulse energy storage, in which the ceramic dielectric is core-shell structured powder of Ba.sub.xSr.sub.1-xTiO.sub.3 coated with SiO.sub.2, and the glass material is alkali-free glass AF45, of which the chemical composition is 63% SiO.sub.2-12% BaO-16% B.sub.2O.sub.3-9% Al.sub.2O.sub.3. AF45 alkali-free glass paste is spin-coated on both sides of the ceramic and calcined to get a layer-structured material of glass-ceramic-glass.
TUNGSTEN CARBIDE POWDER
A tungsten carbide powder 1 includes bonded bodies 10 each including a plurality of tungsten carbide crystal grains 11, in which the bonded bodies 10 include, at a grain boundary 11a between the plurality of tungsten carbide crystal grains 11, a chromium-concentrated region 12 which has a chromium concentration higher than that in the tungsten carbide crystal grains 11.
ZINC OXIDE VARISTOR CERAMICS
Provided according to embodiments of the invention are varistor ceramic formulations that include zinc oxide (ZnO). In particular, varistor ceramic formulations of the invention may include dopants including an alkali metal compound, an alkaline earth compound, an oxide of boron, an oxide of aluminum, or a combination thereof. Varistor ceramic formulations may also include other metal oxides. Also provided according to embodiments of the invention are varistor ceramic materials formed by sintering a varistor ceramic formulation according to an embodiment of the invention. Further provided are varistors formed from such ceramic materials and methods of making such materials.
HIGH STRENGTH, TOUGH, COAL AND COAL BY-PRODUCT BASED COMPOSITE CERAMICS
A composite material, compositions, processes and methods of using coal and coal by-products composite ceramics is provided for use as a safe, non-toxic material for construction, building and architecture components. The composite material disclosed herein is formed from resin/coal aggregates that contain and prevent the release of harmful impurities that naturally occur in both coal and coal by-products while the advantages of coal-based composites are made available to the building industry. The strength, density and porosity of the composites can be tailored within a wide range to fit the final application by controlling the materials, form factor and processing parameters during fabrication.
HIGH PURITY INGOT FOR WAFER PRODUCTION
A method of forming a high purity ingot for wafer production, such as a silicon carbidewafer. Precursors are added to a reactor; at least part of a fiber is formed in the reactor from the precursors using chemical deposition interacting with the precursors; and granular material is then formed from the fiber. The method further includes forming the ingot from the granular material. In one aspect, the chemical deposition can include laser induced chemical vapor deposition. Further, the method can include separating one or more wafers from the ingot for use in semiconductor fabrication.
PRODUCTION OF POROUS ALPHA-ALUMINA SUPPORTS FROM BOEHMITIC DERIVED ALUMINAS
A porous alpha-alumina catalyst support is prepared by (i) preparing a precursor material comprising a boehmitic-derived alumina having a pore volume of at least 0.6 mL/g, wherein the boehmitic-derived alumina is obtained by thermal decomposition of a boehmitic starting material and the boehmitic starting material consists predominantly of block-shaped crystals, and optionally an inorganic bond material; (ii) forming the precursor material into shaped bodies; (iii) calcining the shaped bodies to obtain the porous alpha-alumina catalyst support. The support structure has a high overall pore volume, while keeping its surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The support is useful for a catalyst for producing ethylene oxide by gas-phase oxidation of ethylene.
ZIRCONIA MOLDED BODY SUITABLE FOR DENTAL USE
A zirconia molded body and a dental mill blank may decrease of the translucency of a zirconia sintered body upon firing even when the cooling solvent used for wet processing of the zirconia molded body or dental mill blank by a dental CAD/CAM system is contaminated. This can allow more convenient fabrication of a zirconia sintered body. A zirconia molded body may include zirconia; a stabilizer capable of inhibiting a phase transformation of zirconia; and a binder, and having an open porosity of 25% or less.
Enhancing the Strength of Al-B4C Composites to a High Degree by Mg Addition
A method of making an Al—B.sub.4C composite with Mg addition comprising providing a first mixture of B.sub.4C, Al and Mg powder, producing a powder mixture, adding Mg to the powder mixture, forming pellets, creating a composite, annealing the composite, and forming an Al—Mg—B.sub.4C composite. An Al—B.sub.4C composite with Mg addition comprising Al, Mg comprising 4 wt. %, and B.sub.4C comprising 8 wt. %. An Al—B.sub.4C composite with Mg addition made from the steps comprising providing a first mixture of B.sub.4C, Al and Mg powder, producing a powder mixture, adding Mg to the powder mixture, forming pellets, creating a composite, annealing the composite, and forming an Al—Mg—B.sub.4C composite.
Microwave dielectric ceramic material and preparation method thereof
A temperature-stable modified NiO—Ta.sub.2O.sub.5-based microwave dielectric ceramic material and a preparation method thereof are provided. Using ion doping modification to form solid solution structure is an important measure to adjust microwave dielectric properties, especially the temperature stability. Based on formation rules of the solid solution, ion replacement methods are designed including Ni.sup.2+ ions are replaced by Cu.sup.2+ ions, and (Ni.sub.1/3Ta.sub.2/3).sup.4+ composite ions are replaced by [(Al.sub.1/2Nb.sub.1/2).sub.ySn.sub.1-y].sup.4+ composite ions, which considers that cations with similar ionic radii to Ni.sup.2+ and Ta.sup.5+ ions can be introduced into the NiTa.sub.2O.sub.6 ceramic for doping under the same coordination environment (coordination number=6), and therefore a ceramic material with the NiTa.sub.2O.sub.6 solid solution structure can be obtained. The microwave dielectric ceramic material with excellent temperature stability and low loss is finally prepared by adjusting molar contents of each of doped ions, and its microwave dielectric properties are excellent.
Fiber-reinforced metal-, ceramic-, and metal/ceramic-matrix composite materials and methods therefor
A method is disclosed for forming extrudate filament, which consist essentially of fiber, organic binder, and metal and/or ceramic. The extrudate filament can be spooled, or used to form preforms, and/or assemblages of preforms. In further methods, the extrudate filament and/or preforms can be used to fabricate fiber-reinforced metal-matrix or ceramic-matrix or metal and ceramic matrix composite parts, which consist essentially of fiber in a matrix of metal, or ceramic, or metal and ceramic, respectively.