In joining composite ceramic bodies, at least one ceramic body is a compositionally graded with varying concentrations between two or more ceramic materials. The compositionally graded ceramic body terminates at an interfacial layer that is substantially composed of a single ceramic material. The compositionally graded ceramic body is joined to another ceramic body that may also be compositionally graded or made of a single ceramic material, and an interfacial layer of the other ceramic body is identical in composition with the interfacial layer of the compositionally graded ceramic body. In some embodiments, the ceramic bodies may be joined by diffusion bonding. In some embodiments, the ceramic bodies include a ceramic platen and ceramic stem of a wafer pedestal implemented in a plasma processing apparatus.

The disclosure provides seals for devices that operate at elevated temperatures and have reactive metal vapors, such as lithium, sodium or magnesium. In some examples, such devices include energy storage devices that may be used within an electrical power grid or as part of a standalone system. The energy storage devices may be charged from an electricity production source for later discharge, such as when there is a demand for electrical energy consumption.

A method of producing a bonded body is disclosed in which a ceramic member made of ceramics and a Cu member made of Cu or a Cu alloy are bonded to each other, the method including: a laminating step of laminating the ceramic member and the Cu member in a state where a CuP-based brazing filler material containing 3 mass % to 10 mass % of P and an active metal material are interposed therebetween; and a heating step of heating the ceramic member and the Cu member which are laminated.

[Problem] To obtain a ceramic circuit board having superior crack-resistance with respect to ultrasonic bonding. [Solution] The abovementioned problem is solved by a ceramic circuit board characterized in that a metal circuit board is bonded to one surface of a ceramic substrate and a metal heat radiation plate is bonded to the other surface of the ceramic substrate, wherein the crystal grain size in the metal circuit board is at least 20 m and at most 70 m. This ceramic circuit board can be manufactured by arranging the metal circuit board on one surface of the ceramic substrate and arranging the metal heat radiation plate on the other surface of the ceramic substrate, and bonding in a vacuum of at most 110.sup.3 Pa, at a bonding temperature of at least 780 C. and at most 850 C., for a retention time of at least 10 minutes and at most 60 minutes.

Disclosed are a multi-layer composite ceramic plate and a manufacturing method thereof. The composite ceramic plate includes at least one basic sandwich structure. The manufacturing method includes: preparing a sheet-like green body with ceramic powders; pre-sintering the green body at a pre-sintering temperature lower than the sintering temperature to obtain a pre-sintered ceramic member with certain strength; forming a metal electrode layer on an upper surface of the pre-sintered ceramic member; placing the pre-sintered ceramic member in a mold, with the upper surface coated with the metal electrode layer facing upwards; providing a ceramic precursor layer on the upper surface of the pre-sintered ceramic member; carrying out hot-pressing sintering in the axial direction of the pre-sintered ceramic member at the sintering temperature to form an integral structure, wherein by the hot-pressing sintering, a second ceramic layer is formed by the pre-sintered ceramic member, a first ceramic layer is formed by the ceramic precursor layer, and the metal electrode layer is located between the first ceramic layer and the second ceramic layer to from a basic sandwich structure together with the first ceramic layer and the second ceramic layer.

The invention relates to the use of Dispersion Ceramic Micro-Encapsulated (DCM) nuclear fuel as a meltdown-proof, accident-tolerant fuel to replace uranium dioxide fuel in existing light water reactors (LWRs). The safety qualities of the DCM fuel are obtained by the combination of three strong barriers to fission product release (ceramic coatings around the fuel kernels), highly dense inert ceramic matrix around the coated fuel particles and metallic or ceramic cladding around the fuel pellets.

[Problem] To obtain a ceramic circuit board having superior crack-resistance with respect to ultrasonic bonding.

[Solution] The abovementioned problem is solved by a ceramic circuit board characterized in that a metal circuit board is bonded to one surface of a ceramic substrate and a metal heat radiation plate is bonded to the other surface of the ceramic substrate, wherein the crystal grain size in the metal circuit board is at least 20 m and at most 70 m. This ceramic circuit board can be manufactured by arranging the metal circuit board on one surface of the ceramic substrate and arranging the metal heat radiation plate on the other surface of the ceramic substrate, and bonding in a vacuum of at most 110.sup.3 Pa, at a bonding temperature of at least 780 C. and at most 850 C., for a retention time of at least 10 minutes and at most 60 minutes.

The invention relates to the use of Dispersion Ceramic Micro-Encapsulated (DCM) nuclear fuel as a meltdown-proof, accident-tolerant fuel to replace uranium dioxide fuel in existing light water reactors (LWRs). The safety qualities of the DCM fuel are obtained by the combination of three strong barriers to fission product release (ceramic coatings around the fuel kernels), highly dense inert ceramic matrix around the coated fuel particles and metallic or ceramic cladding around the fuel pellets.

A bonded assembly according to the present embodiment, includes a metal plate and a ceramic substrate bonded to each other through a bonding layer containing Ag. In the bonded assembly, in a measurement region that is formed in a cross section formed by a thickness direction of the bonding layer and an orthogonal direction thereto, and that has a size of a length in the thickness direction of the bonding layera length of 200 m in the orthogonal direction, a Ag-rich region having a Ag concentration of 60 at % or more has an area ratio of 70% or less to a Ag-poor region having a Ag concentration of 50 at % or less.

The invention relates to the use of Dispersion Ceramic Micro-Encapsulated (DCM) nuclear fuel as a meltdown-proof, accident-tolerant fuel to replace uranium dioxide fuel in existing light water reactors (LWRs). The safety qualities of the DCM fuel are obtained by the combination of three strong barriers to fission product release (ceramic coatings around the fuel kernels), highly dense inert ceramic matrix around the coated fuel particles and metallic or ceramic cladding around the fuel pellets.