The present disclosure relates to new materials comprising Al, Co, Fe, and Ni. The new materials may realize a single phase field of a face-centered cubic (fcc) solid solution structure immediately below the solidus temperature of the material. The new materials may include at least one precipitate phase and have a solvus temperature of at least 1000° C. The new materials may include 4.4-11.4 wt. % Al, 4.9-42.2 wt. % Co, 4.6-28.9 wt. % Fe, and 44.1-86.1 wt. % Ni. In one embodiment, the precipitate is selected from the group consisting of the L1.sub.2 phase, the B2 phase, and combinations thereof. The new alloys may realize improved high temperature properties.

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 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.

An electrode (10) is presented including a sheath (14) formed of a ductile material, an outer coating (16) including a flux material, and a core (12) including at least one of flux material and alloying material. The ductile material may be an extrudable subset of elements of a desired superalloy material and the alloying material may include elements that complement the ductile material to form a desired superalloy material when the electrode is melted. The outer coating may be formed of a flexible bonding material or it may be segmented (18, 20) to facilitate bending the electrode onto a spool. Any hygroscopic material of the electrode may be included in the core to protect it from exposure to atmospheric moisture.

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 method of manufacturing includes depositing a braze filler adjacent to a void between a first component and a second component thus holding the components in position before brazing. The first and second components are heated to melt and flow the braze filler into the void. A braze joint is formed between the first and second components by cooling the braze filler. Depositing the braze filler can include laser cladding the braze filler to the first and/or second components adjacent the void. The method also optionally includes welding the first and second components in position with the braze filler adjacent to the void. The braze filler may be deposited as a powder, cold spray, melted brazed filament, spherical ball or any other suitable form.

This disclosure includes the description of a braze alloy composition. The braze composition contains nickel, about 5% by weight to about 25% by weight germanium; and about 1% by weight to about 4% by weight boron. The composition has an amorphous structure, and is free of silicon.

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 eliminating dissimilar metal welds has been disclosed. The method includes the steps of providing a first part having a first alloy composition; providing a second part having a second alloy composition different from the first part; connecting a containment structure to the first part; pouring a powder into the containment structure such that the powder is in contact with the first part; positioning a portion of the second part in the containment structure such that the second part compresses the powder between the first and second parts; and performing hot isostatic pressing (HIP) to consolidate the powder and join the first and second parts together.

In described examples, a transient liquid phase (TLP) metal bonding material includes a first substrate and a base metal layer. The base metal layer is disposed over at least a portion of the first substrate. The base metal has a surface roughness (Ra) of between about 0.001 to 500 nm. Also, the TLP metal bonding material includes a first terminal metal layer that forms an external surface of the TLP metal bonding material. A metal fuse layer is positioned between the base metal layer and the first terminal metal layer. The TLP metal bonding material is stable at room temperature for at least a predetermined period of time.