A composition includes granules in which zirconia particles are aggregated. The granules have an average circularity of 0.81 or greater based on a projected image. Additionally, a layered body includes a first layer and a second layer that comprise granules and are adjacent to each other. The granules in the first layer have an average circularity of 0.70 or smaller based on a projected image. The granules in the second layer have an average circularity of 0.92 or greater based on a projected image.

A ceramic electronic device includes: a multilayer structure; and a cover layer, wherein a concentration of Mn of the cover layer with respect to a main component ceramic is larger than a concentration of Mn of the dielectric layers with respect to a main component ceramic in a capacity section, wherein an average crystal grain diameter of a first dielectric layer is smaller than that of a second dielectric layer, and a concentration of Mn of the first dielectric layer with respect to the main component ceramic is larger than a concentration of Mn of the second dielectric layer with respect to the main component ceramic, in the capacity section.

A ceramic electronic device includes a multilayer structure in which a plurality of dielectric layers and a plurality of internal electrode layers are alternately stacked. Each of the plurality of dielectric layers includes ceramic grains of a main component thereof expressed by (Ba.sub.1-x-yCa.sub.xSr.sub.y)(Ti.sub.1-zZr.sub.z)O.sub.3 (0<x?0.2, 0?y?0.1, 0?z?0.1). D3<D1<D2 is satisfied when an average grain diameter of the ceramic grains of the main component of the plurality of dielectric layers in a section in which each two internal electrode layers is D1, an average grain diameter of the ceramic grains of the main component of first dielectric layers which are located at different height positions from the internal electrode layers is D2, an average grain diameter of the ceramic grains of the main component of second dielectric layers which are located at same height positions of the internal electrode layers is D3.

An article that includes a substrate; a first layer including yttria and zirconia or hafnia, where the first layer has a columnar microstructure and includes predominately the zirconia or hafnia; a second layer on the first layer, the second layer including zirconia or hafnia, ytterbia, samaria, and at least one of lutetia, scandia, ceria, neodymia, europia, and gadolinia, where the second layer includes predominately zirconia or hafnia, and where the second layer has a columnar microstructure; and a third layer on the second layer, the third layer including zirconia or hafnia, ytterbia, samaria, and a rare earth oxide including at least one of lutetia, scandia, ceria, neodymia, europia, and gadolinia, where the third layer has a dense microstructure and has a lower porosity than the second layer.

The present invention relates to a copper ceramic substrate incorporating a ceramic carrier, and a copper layer joined to a surface of the ceramic carrier, wherein the copper layer incorporates at least one first layer, which faces the ceramic carrier and has an average first grain size, and a second layer, which is arranged on the face of the copper layer facing away from the ceramic carrier and has an average second grain size, the second grain size being smaller than the first grain size.

Method of manufacturing a metal-ceramic substrate (1) which, in the finished state, has a ceramic layer (11) and a metal layer (12) extending along a main extension plane (HSE) and arranged one above the other along a stacking direction (S) extending perpendicularly to the main extension plane (HSE) comprising providing the metal layer (12) and the ceramic layer (11) and bonding the metal layer (12) to the ceramic layer (11) in regions to form a first region (B1), which has a materially bonded connection between the metal layer (12) and the ceramic layer (11), and a second region (B2), in which the metal layer (12) and the ceramic layer (11) are arranged one above the other without a materially bonded connection, as seen in the stacking direction (S).

The present invention relates to a polycrystalline diamond compact having multiple polycrystalline diamond sintered bodies and a method for producing the polycrystalline diamond compact. The method for producing the polycrystalline diamond includes: preparing first diamond powder; producing a first polycrystalline diamond sintered body having a diameter smaller than the diameter of a cemented substrate by sintering the first diamond powder under 5 to 6 GPa pressure and 1300 to 1500 C. temperature; positioning the first polycrystalline diamond sintered body in the center of the cemented substrate, and granulating second diamond powder around the first polycrystalline diamond sintered body; and sintering the second diamond powder under 5 to 6 GPa pressure and 1300 to 1500 C. temperature to form a second polycrystalline diamond sintered body. The polycrystalline diamond sintered body has uniform sintered characteristics at the center and outer edges thereof.

This disclosure concerns methods of fabricating porous ceramic supports and supported ceramic membranes, comprising mixing a ceramic powder, a clay powder and a binder to form a mixture, kneading the mixture in an aqueous or non-aqueous medium and a humectant to form a ceramic paste, and aging the ceramic paste for at least 24 h. The ceramic powder is about 70 wt % to about 80 wt % in the ceramic paste. The clay powder is about 5 wt % to about 15 wt % in the ceramic paste. The ceramic powder has an average particle size of about 5 ?m to about 20 ?m. This disclosure also concerns porous ceramic supports and supported ceramic membranes thereof.

A polycrystalline diamond structure comprises a first region and a second region adjacent the first region, the second region being bonded to the first region by intergrowth of diamond grains. The first region comprises a plurality of alternating strata or layers, each or one or more strata or layers in the first region having a thickness in the range of around 5 to 300 microns. The polycrystalline diamond (PCD) structure has a diamond content of at most about 95 percent of the volume of the PCD material, a binder content of at least about 5 percent of the volume of the PCD material, and one or more of the layers or strata in the first region comprise and/or the second region comprises diamond grains having a mean diamond grain contiguity of greater than about 60 percent and a standard deviation of less than about 2.2 percent. There is also disclosed a method of making such a polycrystalline diamond structure.

The present invention relates to refractories with a composition gradient for lining the interior surface of combustion chambers. The invention envisages the use of refractories characterized by the presence of a number of layers with a different chemical composition to form a gradient along the cross section of the material. The presence of the composition gradient serves to combine the corrosion resistance of the surface layer, facing towards the inside of the combustion chamber, with the shock resistance of the bulk material.