Abstract: A multi-layer seal arrangement includes a dissolution barrier between a braze alloy and a ceramic component. The inventive seal is useful for joining a ceramic component to another ceramic component or a metal component, for example. In one example, the braze comprises a gold alloy and the dissolution barrier comprises a layer of alumina on the order of 2-3 microns thick. A titanium wetting layer is provided between the alumina layer and the alloy. A metallization layer provided between the dissolution barrier and the ceramic component in one example comprises a layer of gold between two thin layers of titanium. In one particular example, a platinum mesh is included with the gold of the braze alloy to control braze flow during the brazing operation.

Abstract: A multi-layer seal arrangement includes a dissolution barrier between a braze alloy and a ceramic component. The inventive seal is useful for joining a ceramic component to another ceramic component or a metal component, for example. In one example, the braze comprises a gold alloy and the dissolution barrier comprises a layer of alumina on the order of 2-3 microns thick. A titanium wetting layer is provided between the alumina layer and the alloy. A metallization layer provided between the dissolution barrier and the ceramic component in one example comprises a layer of gold between two thin layers of titanium. In one particular example, a platinum mesh is included with the gold of the braze alloy to control braze flow during the brazing operation.

Abstract: A multi-layer seal arrangement includes a dissolution barrier between a braze alloy and a ceramic component. The inventive seal is useful for joining a ceramic component to another ceramic component or a metal component, for example. In one example, the braze comprises a gold alloy and the dissolution barrier comprises a layer of alumina on the order of 2-3 microns thick. A titanium wetting layer is provided between the alumina layer and the alloy. A metallization layer provided between the dissolution barrier and the ceramic component in one example comprises a layer of gold between two thin layers of titanium. In one particular example, a platinum mesh is included with the gold of the braze alloy to control braze flow during the brazing operation.

Abstract: An erosion resistant ceramic component is synthesized from a silicon oxynitride precursor powder with a sintering aide. The sintering aide, preferably aluminum oxide and/or lutetium oxide are added to the silicon oxynitride precursor powder and ball milled. The composition is then decanted, dried and granulated. The composition is then formed into the shape of the desired component by hot pressing in a graphite die. A heat treatment process may also be applied after hot pressing to further improve erosion resistance by crystallizing amorphous grain boundary phases to provide a ceramic component having sand erosion characteristics superior to electro-formed nickel. The component provides a dielectric constant which is much lower than the dielectric constant of an electro-formed nickel component.

Abstract: Air cleansing apparatus includes an electrostatic precipitator in which the collector plates are made of, for instance, reticulated chemical vapor deposited silicon carbide, or reticulated silicon carbide ceramic coated with titanium nitride, zirconium diboride, or chemical vapor deposited silicon carbide. Microorganisms entrained on the collector plates are thermally degraded or vaporized by microwave radiation directed against the plates during a sterilization period which follows a collection period.

Abstract: A method of joining adjacent, non-coplanar, fiber reinforced composite structures includes machining a plurality of serrations (4) into an edge (6) of a consolidated first fiber reinforced composite structure (2) such that reinforcing fibers continue from a main body (14) of the first fiber reinforced composite structure (2) into the serrations (4). One or more reinforcing fiber plies (16) are then laid up around the serrations (4) to form an unconsolidated second structure such that the serrations (4) protrude through at least one reinforcing fiber ply (16). In addition to the one or more reinforcing fiber plies (16), the unconsolidated second structure also includes a matrix precursor. Sufficient heat and pressure are applied to the unconsolidated second structure and the serrations (4) to consolidate the second structure into a fiber reinforced composite structure (8).

Abstract: A method of joining adjacent, non-coplanar, fiber reinforced composite structures includes machining a plurality of serrations (4) into an edge (6) of a consolidated first fiber reinforced composite structure (2) such that reinforcing fibers continue from a main body (14) of the first fiber reinforced composite structure (2) into the serrations (4). One or more reinforcing fiber plies (16) are then laid up around the serrations (4) to form an unconsolidated second structure such that the serrations (4) protrude through at least one reinforcing fiber ply (16). In addition to the one or more reinforcing fiber plies (16), the unconsolidated second structure also includes a matrix precursor. Sufficient heat and pressure are applied to the unconsolidated second structure and the serrations (4) to consolidate the second structure into a fiber reinforced composite structure (8).

Abstract: The susceptibility of a material to heating by exposure to microwave energy which material has slight or no such susceptibility is improved by mixing it in granular form with a microave reactive agent also in granular form which is capable of substantially responding to microwave energy. An article made from this mixture can be directly heated with microwave energy.

Abstract: An object responsive to microwave energy is enclosed in a thermally insulated enclosure which is substantially transparent to microwave energy and is heated by microwave energy passing through the enclosure. The apparatus includes a chamber which supports the magnetron radiators and has thermal insulated walls and an insulated base on which the object rests.