Embodiments relate to a piezoelectric ceramic and methods of making the same that is suitable for use as a high-power piezoelectric ceramic, and in particular a piezoelectric ceramic that exhibits both good hard properties and good soft properties. Embodiments involve generating the piezoelectric ceramic via the combination of chemical modification/doping and/or a texturing method so that the piezoelectric material exhibits a large figure of merit, as well as other hard and soft properties. The chemical modification involves Cu and Mn doping a piezoelectric material composition having a relaxor-lead titanate based ferroelectric structure. The texturing involves templated grain growth (TGG) texturing using a BaTiO.sub.3 (BT) template.

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.

The present disclosure relates to a micromesh proppant for use in hydraulic fracturing of oil and gas wells. In one embodiment, a process for forming proppant particles includes providing a slurry comprising a ceramic raw material containing alumina, atomizing the slurry into droplets, coating seeds comprising alumina with the droplets to form green pellets, sintering the green pellets to form sintered pellets, and breaking the sintered pellets to form proppant particles comprising a sintered ceramic material and having a size of from about 150 mesh to about 500 mesh and a crush strength at 7,500 psi of from about 1% to about 20%. In one embodiment, a proppant particle includes a sintered ceramic material and having a size of from about 150 mesh to about 500 mesh and a crush strength at 7,500 psi of from about 1% to about 20%.

A particulate filter and method of manufacture. The particulate filter includes intersecting walls that define longitudinally extending channels The intersecting walls comprise a porous ceramic material having a bare microstructure that comprises an interconnected network of porous spheroidal ceramic beads that has an open intrabead porosity within the beads and an interbead porosity defined by interstices between the beads. Catalyst particles are deposited at least partially within the intrabead porosity within the interbead porosity. The bare microstructure has a bimodal pore size distribution in which an intrabead median pore size of the intrabead porosity is less than an interbead median pore size of the interbead porosity. The filter has a trimodal pore size distribution comprising a first peak corresponding to the interbead porosity, a second peak corresponding to the intrabead porosity, and a third peak corresponding to the intrabead porosity as blocked by the catalyst particles.

Disclosed herein are compounds, methods, and tools which comprise composite matrices of tungsten tetraborides and ceramics.

An alumina sintered body having a low dielectric loss tangent and a method for manufacturing the alumina sintered body are provided. An alumina sintered body contains Al.sub.2O.sub.3 99.50 mass % or more, and 99.95 mass % or less and sodium and silicon, wherein at a surface layer A in any given cross-section and a central portion B of the cross-section in a depth direction from the surface layer A, a concentration ratio of sodium to silicon in the surface layer A is smaller than the concentration ratio of sodium to silicon at the central portion B.

Disclosed is a rapid, reproducible solution-based method to synthesize solid sodium ion-conductive materials. The method includes: (a) forming an aqueous mixture of (i) at least one sodium salt, and (ii) at least one metal oxide; (b) adding at least one phosphorous precursor as a neutralizing agent into the mixture; (c) concentrating the mixture to form a paste; (d) calcining or removing liquid from the paste to form a solid; and (e) sintering the solid at a high temperature to form a dense, non-porous, sodium ion-conductive material. Solid sodium ion-conductive materials have electrochemical applications, including use as solid electrolytes for batteries.

Disclosed are methods for forming boron nitride-containing aggregates that exhibit improved wear by attrition, and resulting filled polymers that exhibit significantly improved thermal conductivity. The boron nitride-containing aggregates are prepared according to a method that includes wet granulating boron nitride powder with a granulation solution to form wet boron nitride-containing granules; and drying the wet boron nitride-containing granules to cause evaporation of solvent in the granulation solution, thereby forming boron nitride-containing granules. Sintering achieves the desired boron nitride-containing aggregates.

A ZrO.sub.2—Al.sub.2O.sub.3-based ceramic sintered compact containing tetragonal ZrO.sub.2 particles having a crystallite size of from 5 to 20 nm as a main component and having an α-Al.sub.2O.sub.3 crystallite size of not greater than 75 nm and a relative density of not less than 99% can be produced by preparing a Y.sub.2O.sub.3 partially stabilized ZrO.sub.2—Al.sub.2O.sub.3-based powder having a molar ratio (mol %) of zirconia (ZrO.sub.2) and yttria (Y.sub.2O.sub.3) of from 96.5:3.5 to 97.5:2.5 and a mass ratio (mass %) of ZrO.sub.2 containing Y.sub.2O.sub.3 and alumina (Al.sub.2O.sub.3) of from 85:15 to 75:25, molding this powder by cold isostatic pressing, and then performing sintering to a high density by microwave sintering for 45 to 90 min in an inert gas atmosphere at 1200 to 1400° C. When performing microwave sintering, a heating rate is preferably from 5 to 20° C./min up to 600° C. and from 50 to 150° C./min at 600° C. or higher.

The present disclosure provides a glass ceramic composite electrolyte comprising gadolinium doped ceria and glass composite with desired ionic conductivity in the temperature range of 400 to 600° C., suitable for applications in solid oxide fuel cells. Also disclosed is a process for the preparation of the glass ceramic composite electrolyte.