A bonded body of copper and ceramic includes: a copper member made of copper or a copper alloy and a ceramic member made of an aluminum oxide, the copper member and the ceramic member being bonded to each other; a magnesium oxide layer which is formed on a ceramic member side between the copper member and the ceramic member; and a Mg solid solution layer which is formed between the magnesium oxide layer and the copper member and contains Mg in a state of a solid solution in a Cu primary phase, in which one or more active metals selected from Ti, Zr, Nb, and Hf are present in the Mg solid solution layer.

Provided is a method for manufacturing a metal-layer-joined ceramic base material board, in which at least one scribe line is formed, on each of the front and back surfaces of a ceramic base material board, along dividing lines for dividing the ceramic base material board into a plurality of ceramic boards, a metal board covering at least a portion of the dividing lines is joined to each of the front and back surface of the ceramic base material board, the metal boards are etched along the dividing lines to form a plurality of metal layers, and the plurality of metal layers are joined to each of the front and back surfaces of the ceramic base material board.

A bonded body is formed to configured to join a ceramic member formed of a Si-based ceramic and a copper member formed of copper or a copper alloy, in which, in a joint layer formed between the ceramic member and the copper member, a crystalline active metal compound layer formed of a compound including an active metal is formed on the ceramic member side.

To improve a TCT characteristic of a circuit substrate. The circuit substrate comprises a ceramic substrate including a first and second surfaces, and first and second metal plates respectively bonded to the first and second surfaces via first and second bonding layers. A three-point bending strength of the ceramic substrate is 500 MPa or more. At least one of L1/H1 of a first protruding portion of the first bonding layer and L2/H2 of a second protruding portion of the second bonding layer is 0.5 or more and 3.0 or less. At least one of an average value of first Vickers hardnesses of 10 places of the first protruding portion and an average value of second Vickers hardnesses of 10 places of the second protruding portion is 250 or less.

An aluminum alloy member is made of an aluminum alloy having a Mg concentration set in a range of 0.4 mass % or more and 7.0 mass % or less and a Si concentration set to less than 1 mass %, the aluminum alloy member and a copper member are bonded to each other through solid-phase diffusion, and a compound layer made up of a first intermetallic compound layer that is disposed on the aluminum alloy member side and made of a phase of an intermetallic compound of Cu and Al, a second intermetallic compound layer that is disposed on the copper member side and made of a .sub.2 phase of an intermetallic compound of Cu and Al, and a CuAlMg layer provided between the first intermetallic compound layer and the second intermetallic compound layer is provided in a bonding interface between the aluminum alloy member and the copper member.

The invention relates to sealing a fuel rod composite cladding tube composed of silicon carbide regardless of the fuel rod cladding design architecture (e.g., monolithic, duplex with monolithic SiC on the inside and a composite made with SiC fibers and SiC matrix on the outside) preferably with sealed SiC end plug caps, additionally sealed with an interior braze and exterior SiC final coating, thus providing a double sealed end plug barrier effective at retaining gas tightness and providing mechanical strength for the sealed end joint while providing high chemical resistance.

Provided is a method for manufacturing a metal-layer-joined ceramic base material board, in which at least one scribe line is formed, on each of the front and back surfaces of a ceramic base material board, along dividing lines for dividing the ceramic base material board into a plurality of ceramic boards, a metal board covering at least a portion of the dividing lines is joined to each of the front and back surface of the ceramic base material board, the metal boards are etched along the dividing lines to form a plurality of metal layers, and the plurality of metal layers are joined to each of the front and back surfaces of the ceramic base material board.

A power module substrate includes an insulating substrate and a metal plate. The metal plate is joined to the insulating substrate with a brazing material in between. As to surface roughness of a lateral surface of the metal plate in a thickness direction, the surface roughness of at least a corner part farthest from a center of the metal plate in plan view is larger than the surface roughness of plane parts sandwiching the corner part.

The invention relates to sealing a fuel rod composite cladding tube composed of silicon carbide regardless of the fuel rod cladding design architecture (e.g., monolithic, duplex with monolithic SiC on the inside and a composite made with SiC fibers and SiC matrix on the outside) preferably with sealed SiC end plug caps, additionally sealed with an interior braze and exterior SiC final coating, thus providing a double sealed end plug barrier effective at retaining gas tightness and providing mechanical strength for the sealed end joint while providing high chemical resistance.

A method for producing a ceramic-aluminum bonded body obtained by bonding a ceramic member and an aluminum member, the aluminum member before bonding being composed of aluminum having a purity of 99.0 mass % or higher and 99.9 mass % or lower, includes a heat treatment step of subjecting the aluminum member to a heat treatment in a range of 400 C. or higher and lower than a solidus temperature, and a bonding step of bonding the aluminum member after the heat treatment step and the ceramic member via a brazing filler material including Si.