A braze alloy for joining or repairing ceramic matrix composite (CMC) components comprises a braze composition including silicon at a concentration from about 48 at. % to about 66 at. %, titanium at a concentration from about 1 at. % to about 35 at. %, and an additional element selected from aluminum, cobalt, vanadium, nickel, and chromium. The braze composition comprises a melting temperature of less than 1300 C.

A thermally-actuatable gas valve assembly comprising a ceramic heater is shown and described. The gas valve assembly comprises a housing with a gas inlet and a gas outlet. A bimetal thermal actuator has a valve plug that removably seals the gas outlet from the interior of the housing. The ceramic heater is energizable to cause the thermal actuator to deflect which unseats the valve plug from the gas outlet, thereby placing the gas outlet in fluid communication with the gas inlet and the interior of the housing. A gas heating system is also shown and described in which the gas valve assembly selectively supplies cooking gas to a silicon nitride ceramic igniter. The igniter and the heater are in series such that when a source of alternating current is applied across the igniter and the heater, the igniter reaches the autoignition temperature of the combustion gas before the valve assembly opens

A method to produce a protective surface layer having a predetermined topography on a ceramic matrix composite is described. The method includes applying a slurry layer to a surface of a fiber preform, and drying the slurry layer to form a particulate layer. A surface of the particulate layer is machined to improve surface smoothness and to form a machined surface. A ceramic tape is attached to the machined surface, and a tool comprising one or more features to be imprinted is placed on the ceramic tape, thereby forming a compression assembly. Heat and pressure are applied to the compression assembly to consolidate and bond the ceramic tape to the machined surface, while the one or more features of the tool are imprinted. Thus, a protective surface layer having a predetermined topography is formed.

An environmental resistant coating member includes a SiC long fiber-reinforced ceramics substrate and an environmental barrier coating layer provided on the whole surface of the SiC long fiber-reinforced ceramics substrate. The environmental barrier coating layer includes a SiAlON bonding layer laminated on the SiC long fiber-reinforced ceramics substrate, a mullite layer laminated on the SiAlON bonding layer, a reaction inhibition layer laminated on the mullite layer, and a gradient layer formed on the reaction inhibition layer that gradually changes from a rare-earth disilicate to a rare-earth monosilicate. The reaction inhibition layer includes at least one of an alumina layer, a garnet layer, and a rare-earth (mono)silicate layer. When the reaction inhibition layer includes two or more of these layers, the layers are formed in the order of the alumina layer, the garnet layer, and the rare-earth (mono)silicate layer from a mullite layer side toward a gradient layer side.

There is provided a group III nitride laminate, including: a substrate comprised of silicon carbide; a first layer comprised of aluminum nitride and formed on the substrate; a second layer comprised of gallium nitride and formed on the first layer; and a third layer formed on the second layer and comprised of group III nitride having an electron affinity lower than that of the gallium nitride which is comprised in the second layer, the second layer having a thickness of less than 500 nm, the second layer containing iron at a concentration of less than 1-10.sup.17/cm.sup.3, and the second layer containing carbon at a concentration of less than 110.sup.17/cm.sup.3.

A thermoelectric conversion element includes an element body formed of a thermoelectric conversion material of a silicide-based compound, and electrodes each formed on one surface of the element body and the other surface opposite the one surface. The electrodes are formed of a sintered body of a copper silicide, and the electrodes and the element body are directly joined.

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.

A honeycomb structure including a plurality of porous honeycomb block bodies bound via joining material layers A. Each of the porous honeycomb block bodies includes a plurality of porous honeycomb segments bound via joining material layers B, each of the porous honeycomb segment includes: partition walls that defines a plurality of cells to form flow paths for a fluid, each of cells extending from an inflow end face that is an end face on a fluid inflow side to an outflow end face that is an end face on a fluid outflow side; and an outer peripheral wall located at the outermost periphery. At least a part of the joining material layers A has higher toughness than that of the joining material layers B.

Provided is a bonded substrate mainly for mounting a power semiconductor in which the reliability to a thermal cycle has been enhanced as compared with a conventional one. In a bonded substrate in which a copper plate is bonded to one or both main surface(s) of a nitride ceramic substrate, a bonding layer consisting of TiN intervenes between the nitride ceramic substrate and the copper plate and is adjacent at least to the copper plate, and an Ag distribution region in which Ag atoms are distributed is set to be present in the copper plate. Preferably, an Ag-rich phase is set to be present discretely at an interface between the bonding layer and the copper plate.

A conductive honeycomb structure, comprising: a columnar ceramic honeycomb structure portion comprising an outer peripheral side wall and partition walls each disposed inside the outer peripheral side wall and defining a plurality of cells penetrating from one bottom surface to another bottom surface to form flow paths; a pair of electrode layers disposed on an outer surface of the outer peripheral side wall across a central axis of the honeycomb structure portion; and a pair of metal terminals joined to the respective electrode layers via one or more welded portions, wherein each of the one or more welded portions comprises a welded area of from 2 to 50 mm.sup.2.