An electrostatic chuck includes a ceramic top plate layer made of a beryllium oxide material, a ceramic bottom plate layer made of a beryllium oxide material, a ceramic middle plate layer disposed between the ceramic top plate layer and the ceramic bottom plate layer, an electrode layer disposed between the ceramic top plate layer and the ceramic middle plate layer, and a heater layer disposed between the ceramic middle plate layer and the ceramic bottom plate layer. The electrode layer joins and hermetically seals the ceramic top plate layer to the ceramic middle plate layer, and the heater layer joins and hermetically seals the ceramic middle plate layer to the ceramic bottom plate layer.

Provided is a method for continuously producing a silicon nitride sintered compact for enabling a continuous production of silicon nitride sintered compacts by sintering using a silicon nitride powder having a high β-phase rate. A fired compact 1 housed in a firing jig 2 contains a silicon nitride powder having at least 80% of β-transition rate and 7 to 20 m.sup.2/g of specific surface area together with a sintering additive, where the total content of aluminum element is adjusted not to exceed 800 ppm. The firing jig 2 is supplied into a continuous firing furnace equipped with a closed-type firing container 5 having at its end portions a supplying openable door 3 and a discharging openable door 4 for supplying and discharging the firing jig, a heating mechanism 6 provided on the body periphery of the firing container 5, a conveyance mechanism for supplying/discharging the firing jig into/from the firing container, and a gas-supplying mechanism for supplying an inert gas into the firing container, so that the silicon nitride is heated to a temperature in the range of 1200 to 1800° C. in an inert gas atmosphere and at a pressure of not less than 0 MPa.Math.G and less than 0.1 MPa.Math.G so as to be sintered.

The present invention relates to inorganic fibres having a composition comprising: 61.0 to 70.8 wt % SiO.sub.2; 28.0 to 39.0 wt % CaO; 0.10 to 0.85 wt % MgO other components, if any, providing the balance up to 100 wt %, The sum of SiO.sub.2 and CaO is greater than or equal to 98.8 wt % and the other components comprise less than 0.70 wt % Al.sub.2O.sub.3, if any.

A gas turbine engine component includes a gas turbine engine component body formed of a ceramic matrix composite material having at least one fastener integrally formed with the gas turbine engine component body as a single-piece structure. The gas turbine engine component body initially comprises a rigidized preform structure formed from a polymer based material. The at least one fastener connects the gas turbine engine component body to an engine support structure.

Ceramic matrix composite articles include, for example a first plurality of plies of ceramic fibers in a ceramic matrix defining a first extent, and a local at least one second ply in said ceramic matrix defining a second extent on and/or in said first plurality of plies with the second extent being less than said first extent. The first plurality of plies has a first property, the at least one second ply has at least one second property, and said first property being different from said at least one second property. The different properties may include one or more different mechanical (stress/strain) properties, one or more different thermal conductivity properties, one or more different electrical conductivity properties, one or more different other properties, and combinations thereof.

The present invention focuses on a silicon nitride substrate having high mechanical strength, high thermal conductivity and the like, and takes advantage of such properties to provide: a ceramic substrate capable of providing improvement in a bonding property between a silicon nitride substrate and a ceramic layer which uses a dielectric ceramic material capable of being simultaneously sintered with a low-resistance conductive material such as a low-melting metal (Ag or Cu); and a method for producing the ceramic substrate. The ceramic substrate of the present invention is obtained by stacking and bonding a silicon nitride substrate and a ceramic layer composed of a dielectric ceramic material, wherein: the dielectric ceramic material contains Mg, Al, and Si as main ingredients, and Bi or B as an accessory ingredient; and the ceramic layer includes a region with a high Si element concentration at a bonding interface with the silicon nitride substrate.

Flow path assemblies and methods for forming such flow path assemblies for gas turbine engines are provided. For example, a flow path assembly for a gas turbine engine has a boundary structure, an airfoil, and a locking feature. The boundary structure and the airfoil are formed from a composite material. The boundary structure defines an opening and a cutout proximate the opening, and the airfoil is sized to fit within the opening of the boundary structure. The locking feature is received within the cutout defined by the boundary structure to interlock the airfoil with the boundary structure.

A vaporization core of an electronic vaporization device includes: a porous ceramic substrate; a ceramic covering layer; and a heating film. The ceramic covering layer is combined on a surface of the porous ceramic substrate. The heating film is combined on a surface of the ceramic covering layer away from the porous ceramic substrate. A porosity of the ceramic covering layer is lower than a porosity of the porous ceramic substrate. A plurality of penetrating holes are formed on the ceramic covering layer.

Ceramic welding methods and welded articles are disclosed. The present disclosure shows that transparent and diffuse ceramics can be successfully joined using lasers. The diffuse ceramic welding can be aided by introducing a small gap for optical penetration while no gap is necessary in the transparent ceramics case. Laser welding is more versatile on transparent ceramics since one can focus through the material allowing the joining of more complex geometries and over multiple interaction zones, increasing the ultimate weld volumes.

A method of forming an integral fastener for a ceramic matrix composite component comprises the steps of forming a fiber preform with an opening, forming a fiber fastener, inserting the fiber fastener into the opening, and infiltrating a matrix material into the fiber preform and fiber fastener to form a ceramic matrix composite component with an integral fastener. A gas turbine engine is also disclosed.