A porous ceramic particle includes a porous portion and a dense layer. The porous portion has a plate-like shape and a pair of main surfaces in parallel with each other. The dense layer has porosity lower than that of the porous portion and covers at least one main surface among the pair of main surfaces of the porous portion. A portion of a surface of the porous portion, which is other than the pair of main surfaces, is exposed from the dense layer. It is thereby possible to provide a porous ceramic particle of low thermal conductivity and low heat capacity.

A method for constructing an abradable coating comprises: a slurry layer formation step S2 in which a slurry layer 31 is formed on the surface of a base material 30 using a slurry containing ceramic particles and a solvent; a calcination step S3 in which the slurry layer 31 formed on the surface of the base material 30 is sintered and a sintered layer 35 to be a portion of an abradable coating layer 22 is formed; and a slurry removal step S5 in which extraneous slurry is removed after the abradable coating layer 22 has been formed on the surface of the base material 30, a plurality of the sintered layers 35 having been laminated in the abradable coating layer 22 through a plurality of repeated cycles of the slurry layer formation step S2 and the calcination step S3.

The invention relates to a method for producing a metal or ceramic component, wherein powder or a pre-sintered component is used, and the component is produced via a pressure-supported compacting and sintering step by means of at least one ram. According to the invention, a ram is used, the contact surface of which has an outer flat region and at least one inner region with a concave recess, whereby a component with regions of different porosities is produced during the compacting and sintering step at a maximum temperature (T.sub.1) and a predetermined force. With said method, it is possible to produce a metal or ceramic component in two method steps or preferably in only one method step, in such a way that the component has an outer flat region and at least one inner region with a convex elevation, and wherein the porosity of the outer flat region is significantly lower than the porosity of the inner region. A component of this type can be used preferably as a substrate/carrier for a membrane in a gas separation device or in a fuel or electrolytic cell.

Provided is a large-sized silicon nitride sintered substrate and a method for producing the same. The silicon nitride sintered substrate has a main surface 101a of a shape larger than a square having a side of a length of 120 mm. A ratio dc/de of the density dc of the central area and the density de of the end area of the main surface 101a is 0.98 or higher. The void fraction vc of the central area of the main surface 101a is 1.80% or lower, and the void fraction ve of the end area is 1.00% or lower. It is preferred that the density dc of the central area is 3.120 g/cm.sup.3 or higher, the density de of the end area is 3.160 g/cm.sup.3 or higher, and a ratio ve/vc of the void fraction vc of the central area and the void fraction ve of the end area is 0.50 or higher.

Polycrystalline diamond bodies having an annular region of diamond grains and a core region of diamond grains and methods of making the same are disclosed. In one embodiment, a polycrystalline diamond body includes an annular region of inter-bonded diamond grains having a first characteristic property and a core region of inter-bonded diamond grains bonded to the annular region and having a second characteristic property that differs from the first characteristic property. The annular region decreases in thickness from a perimeter surface of the polycrystalline diamond body towards a centerline axis.

To provide a preparing method of a zirconia mill blank for dental cutting and machining having any one or more of translucency gradation, color gradation and strength gradation after perfect sintering by impregnating a zirconia calcined body with a plurality of impregnating solutions, which can suppress deterioration of the fitting property of a dental prosthesis device prepared from the zirconia mill blank for dental cutting and machining and a zirconia mill blank for dental cutting and machining having any one or more of translucency gradation, color gradation and strength gradation after perfect sintering and suppressing deterioration of the fitting property of a dental prosthesis device prepared from the zirconia mill blank for dental cutting and machining.

To porovide a zirconia mill blank for dental cutting and machining of the present invention is a preparing method of a zirconia mill blank for dental cutting and machining having any one or more of translucency gradation, color gradation and strength gradation after perfect sintering, comprising a step of impregnating a zirconia calcined body with at least two types of impregnating solutions, wherein at least one of the impregnating liquids contains a zirconium component, and in a case in which the total of metal ion concentrations (mass %) contained in each impregnating liquid is defined as C.sub.total, the difference ?C.sub.total which is a difference between C.sub.total of each impregnating liquid is 5.0 or less.

To provide a zirconia mill blank for dental cutting and machining that can impart translucency gradation and color gradation similar to a natural tooth to a zirconia perfect sintered body without the need for special equipment.

To provide a zirconia mill blank for dental cutting and machining comprising two opposing surfaces and a side surface between the two opposing surfaces, wherein the side surface has a rectangular shape in a side view of the zirconia mill blank for dental cutting and machining, and in a case in which one of the two opposing surfaces is defined as surface A, the other surface of the two opposing surfaces is defined as surface B, a surface which is parallel to the surface A and is located at a position of 1.0 mm to 1.5 mm from the surface A toward the surface B in a direction parallel to the side surface is defined as surface C, points which are set to having 0.5 mm of distance on the straight line in the direction parallel to the side surface from the surface C toward the surface B in the area from the surface C to the surface B are defined as point P(1), point P(2), to point P(n) in the order from the surface C, a stabilizer concentration (mol %) at each point is defined as SP(1), SP(2), to SP(n) (n?((shortest distance (mm) between the surface C and the surface B)?2)/0.5), the maximum value of the stabilizer concentration (mol %) is defined as SPmax, the minimum value of the stabilizer concentration (mol %) is defined as SPmin, and the maximum value of ASP(m) defined by the following formula is defined as ?SPmax, the zirconia mill blank for dental cutting and machining has a portion where the value of SPmax?Spmin which is a difference between the SPmax and the SPmin is 0.3 or more, and the ?SPmax is less than 0.5.

[00001]$ ? SP ( m ) = .Math. "\[LeftBracketingBar]" SP ( m ) - SP ( m + 1 ) .Math. "\[RightBracketingBar]" ( m = 1 , 2 , .Math. n - 1 )< Ceramic matrix composite structures with controlled microstructures fabricated using chemical vapor infiltration (CVI) 12054432 · 2024-08-06 · General Electric Company · Jared Hogg Weaver, Gregory Scot CORMAN, Krishan Lal LUTHRA According to a method set forth herein a plurality of preform plies having first and second preform plies can be associated together to define a preform. The preform can be subject to chemical vapor infiltration (CVI) processing to define a ceramic matrix composite (CMC) structure. Part consisting of a ceramic material, comprising a base and a wall 10138739 · 2018-11-27 · Safran Aircraft Engines · Michael PODGORSKI, Ludovic Molliex A part made of a ceramic material, including a portion forming a base and a portion forming a wall, wherein the base consists of a low-porosity ceramic material and the wall is obtained by powder sintering and includes an envelope and a core, the core being within the envelope, the porosity of the core being higher than that of the base and increasing the further it is from the base. Methods of making polycrystalline diamond bodies having annular regions with differing characteristics 10105826 · 2018-10-23 · Diamond Innovations, Inc. · Andrew GLEDHILL, Christopher Long, Alexanne JOHNSON, Joseph RHODES Polycrystalline diamond bodies having an annular region of diamond grains and a core region of diamond grains and methods of making the same are disclosed. In one embodiment, a polycrystalline diamond body includes an annular region of inter-bonded diamond grains having a first characteristic property and a core region of inter-bonded diamond grains bonded to the annular region and having a second characteristic property that differs from the first characteristic property. The annular region decreases in thickness from a perimeter surface of the polycrystalline diamond body towards a centerline axis. $