A chromaticity of zinc oxide is measured. The durability of a zinc oxide varistor is evaluated based on the chromaticity. This provides a varistor with a high durability stably.

The invention relates to ceramic granules with a high UV opacity and high solar reflectance, which is produced by forming a calcined clay mineral powder into green body and re-calcining, featured with a water absorption of 15-35%; ≥97% crystalline content and 90-100% UV opacity. The invention further relates to a method for preparing ceramic granules with a high UV opacity and high solar reflectance and the use thereof for reflectance-improving application on building surface for the purpose of energy conservation.

A zirconia sintered body comprising 3.0 wt % or more and 30.0 wt % or less of aluminum in terms of Al.sub.2O.sub.3 and a remainder is zirconia containing 2 mol % or more and 4 mol % or less of erbia, in which the zirconia sintered body includes grains of aluminum oxide, and a total light transmittance with respect to a D65 light source at a sample thickness of 1.0 mm is 10% or less.

The present disclosure generally relates to silicon carbide crystals which may be used in optical applications, and to methods for producing the same. In one form, a composition includes an aluminum doped silicon carbide crystal having residual nitrogen and boron impurities. The concentration of aluminum in the silicon carbide crystal is greater than the combined concentrations of nitrogen and boron in the silicon carbide crystal, and the silicon carbide crystal includes an optical absorption coefficient of less than about 0.4 cm.sup.−1 at a wavelength in a range between about 400 nm to about 800 nm.

An optical device includes a vanadium compensated, high resistivity, SiC single crystal of 6H or 4H polytype, for transmitting light having a wavelength in a range of from 420 nm to 4.5 μm. The device may include a window, lens, prism, or waveguide. A system includes a source for generating light having a wavelength in a range of from 420 nm to 4.5 μm, and a device for receiving and transmitting the light, where the device includes a vanadium compensated, high resistivity, SiC single crystal of 6H or 4H polytype. The disclosure also relates to crystals and methods for optical applications, including an aluminum doped SiC crystal having residual nitrogen and boron impurities, where the aluminum concentration is greater than the combined concentrations of nitrogen and boron, and where an optical absorption coefficient is less than about 0.4 cm.sup.−1 at a wavelength between about 400 nm to about 800 nm.

The invention relates to a method for obtaining ceramic spheres from aluminosilicates, comprising: dry-milling a percentage of the aluminosilicates and wet-milling the remaining percentage; mixing the aluminosilicates obtained from the dry- and wet-milling processes with a binding additive; granulating same; drying the resulting granules; sieving the resulting granules in order to separate same into sub-groups; and sintering the granules obtained at a temperature between 800° and 1500° C.

The present invention relates to a method for manufacturing a zirconia block for a dental prosthesis having a layered color gradient by a water absorption rate, in which the permeation degree of a coloring solution is controlled by setting a different particle size of powder for each layer of the zirconia block on the basis of the property that the amount of water absorption per hour is differentiated according to the particle size of powder, and as a result, the zirconia block is constituted so as to realize an esthetically excellent resultant product with the same color as natural teeth without carrying out the existing coloring liquid process for zirconia.

In an example of a three-dimensional (3D) printing method, a ceramic build material is applied. A liquid functional material, including an anionically stabilized susceptor material, is applied to at least a portion of the ceramic build material. A sintering aid/fixer fluid, including a cationically stabilized amphoteric alumina particulate material, is applied to the at least the portion of the ceramic build material. The applied anionically stabilized susceptor material and the applied cationically stabilized amphoteric alumina particulate material react to immobilize the anionically stabilized susceptor material, thereby patterning the at least the portion of the ceramic build material.

A chamber component for a processing chamber comprises a ceramic body consisting of a sintered ceramic material consisting essentially of one or more phase of Y.sub.2O.sub.3—ZrO.sub.2. The ceramic material consists essentially of 55-65 mol % Y.sub.2O.sub.3 and 35-45 mol % ZrO.sub.2.

The present invention provides a method for producing a powder containing zirconia particles and a fluorescent agent that enables easy production of a zirconia sintered body having both high translucency and high strength despite containing a fluorescent agent. The present invention relates to a method for producing a zirconia particle- and fluorescent agent-containing powder, comprising: a mixing step of mixing a zirconia particle-containing slurry and a liquid-state fluorescent agent; and a drying step of drying the slurry containing the zirconia particles and the fluorescent agent. Preferably, the fluorescent agent comprises a metallic element, and the powder comprises the fluorescent agent in an amount of 0.001 to 1 mass % in terms of an oxide of the metallic element relative to a mass of zirconia. Preferably, the zirconia particles have an average primary particle diameter of 30 nm or less. Preferably, the zirconia particles comprises 2.0 to 9.0 mol % yttria.