Patent classifications
C04B2235/75
CEMENTED TUNGSTEN CARBIDE BODY AND METHOD OF FORMING THE CEMENTED TUNGSTEN CARBIDE BODY
A cemented tungsten carbide body is formed by mixing a tungsten carbide powder and a cobalt powder together to form a powder mixture. The tungsten carbide powder makes up greater than or equal to 80 weight percent of the powder mixture, while the cobalt binder powder makes up about 1.5 weight percent to about 20 weight percent of the powder mixture. Next, the powder mixture is compacted to form a green compact, and a boron nitride coating is applied to a surface of the green compact to form a coated compact. The coated compact is sintered at a temperature sufficient to melt the cobalt powder, such that boron from the boron nitride coating diffuses into the compact and creates a gradient of metallic cobalt and boron extending inward from the surface. The metallic cobalt content increases from the surface inward, while the boron content decreases from the surface inward.
Multilayer oxide ceramic body with aligned sintering behaviour
The invention relates to multilayer oxide ceramic bodies and in particular presintered multilayer oxide ceramic blanks and oxide ceramic green bodies, which comprise at least two different layers and are suitable for dental applications, wherein at least one layer contains La.sub.2O.sub.3 and the at least two different layers differ in their content of La.sub.2O.sub.3. These bodies can be thermally densified by further sintering without distortion and are therefore particularly suitable for the production of dental restorations. The invention also relates to a process for the production of such multilayer oxide ceramic bodies as well as a process for the production of dental restorations using the multilayer oxide ceramic bodies.
MULTILAYER CERAMIC CAPACITOR
A multilayer ceramic capacitor include: a ceramic body including first and second surfaces opposing each other and third and fourth surfaces connecting the first and second surfaces; a plurality of internal electrodes disposed inside the ceramic body and exposed to the first and second surfaces, the plurality internal electrodes each having one end exposed to the third or fourth surface; and first and second side margin portions disposed on sides of the internal electrodes exposed to the first and second surfaces. A dielectric composition of the first and second side margin portions is different from a dielectric composition of the ceramic body, and a dielectric constant of the first and second side margin portions is lower than a dielectric constant of the ceramic body.
Method of Manufacturing a Zirconium Dioxide Green Body with Color and Translucency Gradients
The invention relates to a method of manufacturing a ceramic molding, comprising the following steps: a) providing three or more ceramic powder layers that are arranged in layers, one on top of the other, to form a compression-molded element and sintering the compression-molded element obtained in step b) to form a ceramic molding, characterized in that the ceramic powder layers have different compositions, each ceramic powder layer comprising a mixture of at least two different base powders and each base powder containing at least 80 wt. % ZrO.sub.2 and at least 0.02 wt. % Al.sub.2O.sub.3, each weight amount being relative to the total weight of the constituents of the base powder.
Magnesium-based thermoelectric conversion material, magnesium-based thermoelectric conversion element, and method for producing magnesium-based thermoelectric conversion material
A magnesium-based thermoelectric conversion material made of a sintered compact of a magnesium compound, in which, in a cross section of the sintered compact, a Si-rich metallic phase having a higher Si concentration than in magnesium compound grains is unevenly distributed in a crystal grain boundary between the magnesium compound grains, an area ratio of the Si-rich metallic phase is in a range of 2.5% or more and 10% or less, and a number density of the Si-rich metallic phase having an area of 1 μm.sup.2 or more is in a range of 1,800/mm.sup.2 or more and 14,000/mm.sup.2 or less.
Zirconium Dioxide Green Body with Color and Translucency Gradients
The invention relates to a sintered molding with a color gradient for use in the manufacture of dental restorations, obtainable by sintering a compression-molded element comprising five or more different ceramic powder layers, each powder layer comprising at least two different base powders and each base powder containing at least 80 wt. % ZrO.sub.2, each weight amount being relative to the total weight of the base powder.
Ceramic matrix composite articles and methods for forming same
A ceramic matrix composite article includes a melt infiltration ceramic matrix composite substrate comprising a ceramic fiber reinforcement material in a ceramic matrix material having a first free silicon proportion, and a melt infiltration ceramic matrix composite outer layer comprising a ceramic fiber reinforcement material in a ceramic matrix material having a second free silicon proportion disposed on an outer surface of at least a portion of the substrate, or a polymer impregnation and pyrolysis ceramic matrix composite outer layer comprising a ceramic fiber reinforcement material in a ceramic matrix material having a second free silicon proportion disposed on an outer surface of at least a portion of the substrate. The second free silicon proportion is less than the first free silicon proportion.
Ferrite composition and multilayer electronic component
A ferrite composition includes main-phase particles, first sub-phase particles, second sub-phase particles, and a grain boundary. At least 10% or more of the main-phase particles contain a portion whose Zn concentrations monotonously decrease from a particle surface toward a particle central part along a length of 50 nm or more. The first sub-phase particles contain Zn.sub.2SiO.sub.4. The second sub-phase particles contain SiO.sub.2. A total area ratio of the first sub-phase particles and the second sub-phase particles is 30.5% or more.
Method for Producing or Modifying Silicon Carbide-Containing Articles
A method for making an article comprising silicon carbide. The method includes producing an article including silicon carbide via additive manufacturing. The method further includes heating via at least one laser beam in a site-selective and locally limited manner a surface of the article so as to cause at least one of ablation and chemical modification of the surface.
FERRITE SINTERED BODY AND COIL COMPONENT
A ferrite sintered body contains Fe, Mn, Zn, Cu, and Ni. Supposing that Fe, Mn, Zn, Cu, and Ni are converted into Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO, respectively, and the sum of the contents of Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO is 100 mol %, the sum of the contents of Fe.sub.2O.sub.3 and Mn.sub.2O.sub.3 is 48.47 mol % to 49.93 mol %, the content of Mn.sub.2O.sub.3 is 0.07 mol % to 0.37 mol %, the content of ZnO is 28.95 mol % to 33.50 mol %, and the content of CuO is 2.98 mol % to 6.05 mol %. Furthermore, 102 ppm to 4,010 ppm Zr in terms of ZrO.sub.2 and 10 ppm to 220 ppm Al in terms of Al.sub.2O.sub.3 are contained per 100 parts by weight of the sum of the amounts of contained Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO.