Abstract: An article, such as an airfoil having a melting temperature of at least about 1500° C. and comprising a first piece and a second piece joined by a braze to the first piece. The first piece comprises one of a first niobium-based refractory metal intermetallic composite and a first molybdenum-based refractory metal intermetallic composite, and the second piece comprises one of a second niobium-based refractory metal intermetallic composite and a second molybdenum-based refractory metal intermetallic composite. The braze joining the first piece to the second piece comprises a first metallic element and a second metallic element, wherein the first metallic element is one of titanium, palladium, zirconium, niobium, and hafnium, and wherein the second metallic element is one of titanium, palladium, zirconium, niobium, hafnium, aluminum, chromium, vanadium, platinum, gold, iron, nickel, and cobalt, the first metallic element being different from the second metallic element.

Abstract: A method of repairing a defect in a casting or cast article, where the defect comprises at least one of a manufacturing, intentional, or service-related defect. The cast article can comprise a casting core and a casting, the casting core comprising a bumper that creates a thin region, namely the defect. One method of repairing the bumper hole defect comprises locating the defect area in the cast article; removing an area of the casting at the defect area; removing an area of the casting core including the bumper at the defect area, where the removing the area of the casting at the defect area and removing an area of the casting core including the bumper at the defect area create a hole; positioning repair material in the hole; heating the defect area, the repair material and the area of the casting at the defect area to melt the repair material and area of the casting at the defect area into a molten material; and re-solidifying the molten material to form a repaired casting.

Abstract: A group of alloys suitable for use in a high-temperature, oxidative environment, a protective coating system comprising a diffusion barrier that comprises an alloy selected from the group, an article comprising the diffusion barrier layer, and a method for protecting an article from a high-temperature oxidative environment comprising disposing the diffusion barrier layer onto a substrate are presented.

Abstract: A method of introducing small amounts of a refractory element into a vapor deposition coating. A second material (30), containing at least two elements which are desired to be deposited as a coating on a base material, has placed over it a first material (20) substantially comprising such two elements and a refractory element. The first material (20) is adapted to permit transport of the at least two elements in the second material (30) through the first material (20) when the first (20) and second (30) material are in a molten state and in touching contact with the other so as to permit evaporation of the two elements and the refractory element from an exposed surface. Heat is supplied to the first (20) and second (30) materials to permit evaporation of the at least two elements of second material (30) and the refractory element in the first material (20), and the resulting vapors are condensed as a deposit on a base material (50).

Abstract: An environmentally resistant coating (34) for improving the oxidation resistance of a niobium-based refractory metal intermetallic composite (Nb-based RMIC) at high temperatures, the environmentally resistant coating (34) comprising silicon, titanium, chromium, and niobium. The invention includes a turbine system (10) having turbine components (11) comprising at least one Nb-based RMIC, the environmentally resistant coating (34) disposed on a surface (33) of the Nb-based RMIC, and a thermal barrier coating (42) disposed on an outer surface (40) of the environmentally resistant coating (34). Methods of making a turbine component (11) having the environmentally resistant coating (34) and coating a Nb-based RMIC substrate (32) with the environmentally resistant coating (34) are also disclosed.

Abstract: An airfoil having a melting temperature of at least about 1500° C. and comprising a first piece and a second piece joined by a braze to the first piece. The first piece comprises one of a first niobium-based refractory metal intermetallic composite and a first-based refractory metal intermetallic composite, and the second piece comprises one of a second niobium-based refractory metal intermetallic composite and a second molybdenum-based refractory metal intermetallic composite. The braze joining the first piece to the second piece is a semi-solid braze that comprises a first component and a second component.

Abstract: A on-line method is provided for detecting wear and/or damage to gas turbine parts. Preferred embodiments of the invention provide a gas turbine comprising parts with smart coatings and collection and detection means to measure wear and erosion of gas turbine parts. In other preferred embodiments, smart coatings are provided comprising chemical taggants that can be collected and detected downstream, thus providing an on-line or in situ evaluation technology for wear and damage to gas turbine parts.

Abstract: The present invention provides an airfoil body having a first wall including a plurality of ribs. An outer wall formed of a high temperature foil is attached to the ribs so as to form a plurality of channels. The first wall is protected from hot flowpath gases by the outer wall and by cooling air flowing through the channels.

Abstract: A wall structure for a gas turbine engine component is provided which comprises a wall having a first side facing a flow of hot gases and a second side exposed to a source of cooling fluid. The wall has a plurality of holes formed therethrough, and an outer layer disposed on the first side. The holes greatly increase the wetted surface area of the wall exposed to cooling flow.

Abstract: A turbine airfoil is provided having an integral tip cap and a pair of tip walls which extend radially outward past the tip cap to form a squealer tip. A coaxial pair of first and second holes extend through the tip cap and one of the tip walls respectively at an acute inclination angle, with the first hole being disposed so as to direct impingement cooling air on the tip wall having the second hole. A protective layer comprising a high temperature foil is disposed on the tip wall having the second hole therein.

Abstract: A protected article includes a nickel-base superalloy substrate, an interlayer overlying the substrate, and a protective layer overlying the interlayer. The protective layer has a composition comprising at least one of rhodium, platinum, palladium, and ruthenium. In one composition, palladium is present in an amount of from about 1 to about 41 atomic percent; platinum is present in an amount of about (40+atomic percent palladium) atomic percent for palladium ranging from about 1 atomic percent to about 14 atomic percent and up to about 54 atomic percent for palladium ranging from about 15 atomic percent up to about 41 atomic percent; rhodium is present in an amount of at least about 24 atomic percent; zirconium, hafnium, titanium, and mixtures thereof are present in an amount of from zero up to about 5 atomic percent; and ruthenium is present in an amount of from zero up to about 5 atomic percent, balance impurities.

Abstract: An alloy comprising rhodium, aluminum, and chromium, wherein a microstructure of the alloy comprises a face-centered-cubic phase and a B2-structured phase and is essentially free of an L12-structured phase at temperatures greater than about 1000° C., and a gas turbine engine component comprising the alloy.

Abstract: Methods for repairing and manufacturing a gas turbine airfoil, and the airfoil repaired and manufactured with such methods are presented with, for example, the repair method comprising providing an airfoil having specified nominal dimensions, the airfoil comprising a first material, the first material having a creep life and a fatigue life, the airfoil further comprising a leading edge section and a trailing edge section; removing at least one portion of at least one section of the airfoil to create at least one deficit of material for the airfoil relative to the specified nominal dimensions, the at least one section selected from the group consisting of the leading edge section and the trailing edge section; providing at least one insert comprising a second material, the second material having a creep life that is at least substantially equal to the creep life of the first material, and a fatigue life that is at least substantially equal to the fatigue life of the first material; and disposing the at least o

Abstract: An airfoil having a melting temperature of at least about 1500° C. and comprising a first piece and a second piece joined by a braze to the first piece. The first piece comprises one of a first niobium-based refractory metal intermetallic composite and a first molybdenum-based refractory metal intermetallic composite, and the second piece comprises one of a second niobium-based refractory metal intermetallic composite and a second molybdenum-based refractory metal intermetallic composite. The braze joining the first piece to the second piece comprises one of germanium and silicon, and one of chromium, titanium, gold, aluminum, palladium, platinum, and nickel. This abstract is submitted in compliance with 37 C.F.R. 1.72(b) with the understanding that it will not be used to interpret or limit the scope of or meaning of the claims.

Abstract: A superalloy weld composition includes: up to about 5.1 wt % Co; about 7.2 to about 9.5 wt % Cr; about 7.4 to about 8.4 wt % Al; about 4.3 to about 5.6 wt % Ta; about 0.1 to about 0.5 wt % Si; about 0.1 to about 0.5 wt % Hf; up to about 0.05 wt % C; up to about 0.05 wt % B; about 0 to about 2.2 Re; about 2.7 to about 4.4 wt % W; and balance Ni and typical impurities.

Abstract: An airfoil having a melting temperature of at least about 1500° C. and comprising a first piece and a second piece joined at a bonded region to the first piece by a diffusion bond. The first piece comprises one of a first niobium-based refractory metal intermetallic composite and a first molybdenum-based refractory metal intermetallic composite. The second piece comprises one of a second niobium-based refractory metal intermetallic composite and a second molybdenum-based refractory metal intermetallic composite. The diffusion bond is formed from a first metallic element disposed on a first surface of the first piece and a second metallic element disposed on at least one of the first surface and a second surface of the second piece, the second surface contacting the first surface, wherein the first and second metal form a composition having a melting temperature less than about 1400° C. This abstract is submitted in compliance with 37 C.F.R. 1.

Abstract: A method for providing a protective coating on a metal-based substrate is disclosed. The method involves the application of an aluminum-rich mixture to the substrate to form a discontinuous layer of aluminum-rich particles, followed by the application of a second coating over the discontinuous layer of aluminum-rich particles. Aluminum diffuses from the aluminum-rich layer into the substrate, and into any bond coat layer which is subsequently applied. Related articles are also described.

Abstract: Methods for repairing and manufacturing a gas turbine airfoil, and the airfoil repaired and manufactured with such methods are presented with, for example, the repair method comprising providing an airfoil having specified nominal dimensions, the airfoil comprising a first material, the first material having a creep life and a fatigue life, the airfoil further comprising a leading edge section and a trailing edge section; removing at least one portion of at least one section of the airfoil to create at least one deficit of material for the airfoil relative to the specified nominal dimensions, the at least one section selected from the group consisting of the leading edge section and the trailing edge section; providing at least one insert comprising a second material, the second material having a creep life that is at least substantially equal to the creep life of the first material, and a fatigue life that is at least substantially equal to the fatigue life of the first material; and disposing the at least o

Abstract: Methods for repairing and manufacturing a gas turbine blade, and the gas turbine blade repaired and manufactured with such methods are presented with, for example, the repair method comprising providing a gas turbine blade, the blade comprising a blade tip and a blade body; removing at least one portion of the blade tip; providing at least one freestanding tip insert; and disposing the at least one tip insert onto the gas turbine blade body such that the at least one tip insert replaces the at least one removed portion of the blade tip.

Abstract: The present invention provides for a squealer tip to include some proportion of a highly oxidation-resistant material, and a method for casting same, such that if any environmental coating were removed, the tip would retain some increased level of environmental resistance. The oxidation-resistant material optionally may also be a high abrasion resistance material, such that recession of the tip due to rubbing against a stator would be reduced. In a preferred embodiment, an abrasion-resistant and/or oxidation-resistant material is placed and suitably anchored into the tip region of a wax precursor used to cast a turbine airfoil. During the casting operation, the abrasion-resistant and/or oxidation-resistant material is not completely melted. As the alloy used to form the majority of the turbine blade solidifies, the abrasion and/or oxidation resistant material is incorporated into the turbine airfoil by the solidification of the alloy around it.