A rotor for at least one of a turbine and a compressor of a supercharging device may include a shaft defining an axis of rotation and at least one impeller. The at least one impeller may have a thread which is arranged coaxially to the axis of rotation. The shaft may include a complementary thread which is arranged coaxially to the axis of rotation. The shaft and the at least one impeller may be secured together via the respective threads. The shaft and the at least one impeller may be fixed with respect to one another via at least one of a soldered connection, a welded connection, an adhesive bond, a clamped connection and a crystallization connection.

Nickel base superalloys, including in some embodiments 5% to 7% Fe, which were previously developed and used for their corrosion resistance, also possess favorable characteristics for use as a braze filler in repair or joining of superalloy substrates, such as those used to form turbine engine blades and vanes, heat exchangers, vessels, and piping. In particular, such corrosion-resistant nickel base superalloys have favorable characteristics for wide-gap brazing of gaps greater than one millimeter in superalloy substrates that preserves favorable material properties throughout the braze region in the substrate.

A method for assembling a set including an inner wall, a shrouded outer wall and an intermediate element, each presenting substantially circular sections, the shrouded outer wall presenting a shape substantially complementary to a shape of outer and inner surfaces of the intermediate element, and whose inner surface covers the outer surface of the intermediate element. In particular, the method includes a step of placing a brazing sheet, whose melting temperature is lower than melting temperatures of other elements of the set, over an assembly surface in contact with another assembly surface, and a step of heating, by a furnace, a set including the outer or inner walls and the intermediate element between which is interposed a brazing sheet so as to fix the outer or inner wall by brazing on the intermediate element.

A nickel braze alloy may include less than about 2.0 wt. % aluminum, about 18.0-23.0 wt. % cobalt, about 12.0-15.0 wt. % chromium, about 3.8-4.5 wt. % molybdenum, about 0.8-1.5 wt. % niobium, about 1.8-3.0 wt. % tantalum, less than about 2.0 wt. % titanium, about 2.0-3.5 wt. % tungsten, about 0.8-1.2 wt. % boron, about 0.02-0.10 wt. % carbon, about 0.03-0.06 wt. % zirconium, and a balance of nickel and minor amounts of impurities.

Single-airfoil vanes each having an inner platform, an outer platform, and an airfoil are obtained by three-dimensionally weaving a fiber blank in a single piece, by shaping the fiber blank to obtain a single-piece fiber preform, and by densifying the preform with a matrix to obtain a vane of composite material forming a single piece with inner and outer platforms incorporated therein. A plurality of vanes is assembled together at an intermediate stage of densification to form a multi-airfoil composite material guide vane sector for a turbine nozzle or a compressor diffuser and the assembled-together vanes are bonded together.

A superalloy component such as a gas turbine engine blade (40) having a ceramic thermal barrier coating (41) is repaired using a textured repair foil (30). A degraded region of the thermal barrier coating is removed (14) and the underlying superalloy material surface is prepared (16) for re-coating. The repair foil is includes a layer of boron-free braze material (34) and a layer of superalloy material (32) having a textured surface (36). The foil is brazed (18) to the prepared surface during a solution heat treatment effective to homogenize the braze (20). A new area of thermal barrier coating (46) is applied over the foil with a bond that is enhanced by the texturing of the foil surface.

A staged fuel injector comprises a pilot inner air swirler arranged along a centre axis of the injector, a pilot fuel swirler arranged radially outboard of the pilot inner air swirler, a main inner air swirler arranged radially outboard of the pilot fuel swirler and a main fuel swirler arranged radially outboard of the pilot fuel swirler. A fuel feed arm is arranged in fluid communication with the pilot fuel swirler and the main fuel swirler for delivering fuel to the pilot fuel swirler and the main fuel swirler and a heat protective casing enclosing the fuel feed arm, the pilot fuel swirler and the main fuel swirler.

An active braze alloy composition is described, including nickel; or a combination of nickel and cobalt; about 2% by weight to about 30% by weight germanium; and about 1% by weight to about 5% by weight boron and about 0.5% by weight to about 5% by weight of at least active element. The composition is free of silicon. Braze alloy joints formed of the braze alloy composition, and located in various devices, structures, and machines, are also described. A related method for repairing a crack or other cavity within a metal component, using the braze composition, is further described.

A method of selective laser brazing is provided. The method includes providing a powder including a plurality of parent core particles and a plurality of braze particles, setting a temperature of an energy source, applying the energy source to the powder, and allowing the heated powder to solidify. The plurality of parent core particles are fused together by the plurality of braze material into a desired component.

A process of fabricating a shield, a process of preparing a component, and an erosion shield are disclosed. The process of fabricating the shield includes forming a near-net shape shield. The near-net shape shield includes a nickel-based layer and an erosion-resistant alloy layer. The nickel-based layer is configured to facilitate secure attachment of the near-net shaped to a component. The process of preparing the component includes securing a near-net shape shield to a substrate of a component.