Abstract: A water machinery runner, which is highly reliable and is so excellent in wear and corrosion resistances that it can be used even under conditions where sediment is contained in a fluid includes crown 21, band 22 and blade 23 of a water machinery runner 2 to be rotated by a working fluid or a fluid flowing in a passage. The elements of the machinery runner are coated on at least portions of their individual surfaces with a first surface film containing a metal, as selected from the group consisting of Ni, Cr and Co, and a chromium carbide, and a second surface film containing a metal, as selected from the group consisting of Ni, Cr and Co, and a tungsten carbide.

Abstract: The present invention relates to a rotor of a vacuum pump comprising a rotatable shaft and a plurality of spaced apart parallel rotor disks secured to said rotatable shaft, such rotor being provided with a corrosion-resistant protective coating formed by a layer of polymeric material. The protective coating of the present invention may apply to any of the stationary or rotational parts which are disposed within a pump body and may be exposed to corrosive gases.

Abstract: A bond coat of a thermal barrier coating system for components designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The composition of the bond coat has graded thermal expansion properties that moderate the transition between a metal substrate and a thermal-insulating ceramic layer of a TBC protecting the substrate, while also reducing the service temperature of the bond coat so as to reduce its rate of oxidation. Preferably, the bond coat has multiple layers, with the coefficients of thermal conductivity of the individual bond coat layers being very close to that of the substrate in order to promote heat transfer from the outward layer of the bond coat to the substrate. By minimizing the service temperature of the bond coat while grading the thermal expansion properties through the coating system, a more spall-resistant coating system is achieved.

Abstract: An electroformed sheath is disclosed for protecting composite components of a part, such as a fan blade of a modern gas turbine engine. The electroformed sheath includes a sheath body having a leading edge; a pressure side and an opposed suction side of the body that meet at the leading edge and extend away from the leading edge to define a sheath cavity therebetween; a head section of the body between the leading edge and the sheath cavity; and an electrically conductive mandrel insert positioned between the pressure and suction sides of the body. In manufacture of the electroformed sheath, the mandrel insert is secured in an appropriate mandrel having an exterior surface approximating the blade's airfoil configuration. The leading edge, head section and pressure and suction sides are electroplated around the mandrel insert so that the insert remains in the sheath body after removal of the mandrel.

Abstract: Disclosed is an impeller made from titanium or a titanium alloy. Desirably, the titanium or titanium alloy is cast into the impeller.

Abstract: A surface defect in a gamma titanium aluminide article is repaired by weld repairing the defect and thereafter sealing the surface-connected cracks in the weldment. The surface-connected cracks are repaired by applying to the region of the weldment a powder of a brazing filler metal that is compatible with the gamma titanium aluminide alloy and with the weldment, and thereafter heating the article to a brazing temperature above the liquidus of the brazing filler metal. The article is preferably hot isostatically pressed after the repair is completed to close internal defects that cannot otherwise be closed due to the surface connected cracks.

Abstract: An iron-nickel superalloy of the type IN 706 has an addition of 0.02 to 0.3 percent by weight of boron and/or 0.05 to 1.5 percent by weight of hafnium. By means of this addition, a virtual doubling of the ductility is achieved as compared with an addition-free iron-nickel superalloy of the type IN 706, while the hot strength is reduced only slightly. The alloy is particularly suitable as a material for rotors of large gas turbines. It has a sufficiently high hot strength. When locally acting temperature gradients arise unwanted stresses can occur to only a slight extent because of the high ductility of the alloy.

Abstract: A lightweight high temperature rotor blade attachment structure for use in a gas turbine engine. The lightweight high temperature rotor blade attachment lug being cast of a single crystal alloy and the lug is then bonded to a conventional nickel based wheel. A circular arc firtree is utilized to connect the insertable turbine blade between a pair of circumferentially spaced lugs that have been bonded to the turbine disk. In an alternate form of the present invention the attachment lug includes an internal cooling passage for receiving cooling fluid from a compressor. More particularly, the present invention discloses a single crystal attachment lug that is bonded to a powdered metal nickel alloy rotor disk and includes internal cooling passages, and in one form is designed for use with turbine blades that do not have a platform.

Abstract: A improved thermal barrier coating and method for producing and applying such is disclosed herein. The thermal barrier coating includes a high temperature substrate, a first bond coat layer applied to the substrate of MCrAlX, and a second bond coat layer of MCrAlX with particles of a particulate dispersed throughout the MCrAlX and the preferred particulate is Al.sub.2 O.sub.3. The particles of the particulate dispersed throughout the second bond coat layer preferably have a diameter of less then the height of the peaks of the second bond coat layer, or a diameter of less than 5 .mu.m. The method of producing the second bond coat layer may either include the steps of mechanical alloying of particles throughout the second bond coat layer, attrition milling the particles of the particulate throughout the second bond coat layer, or using electrophoresis to disperse the particles throughout the second bond coat layer.

Abstract: A nickel-base gamma-sigma intermetallic matrix composite material suitable for forming gas turbine engine components and structural coatings for such components. The composite material contains, in weight percent, about 20 to 50 chromium, about 0 to 32 molybdenum, and about 0.5 to 7 silicon, with the balance being nickel and incidental impurities. In addition, the composite material may contain aluminum and titanium in amounts of up to about 7 and 3 weight percent, respectively. The resulting intermetallic matrix composite material is characterized by a sigma volume fraction of greater than 30 percent, preferably at least about 50 percent, and may have a dendritic, fibrous or lamellar microstructure. The composite material can be cast to form a component, or deposited by known techniques to form a structural coating on a component.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: A crack weld repair and method, particularly, for a gas turbine engine blade or other metallic component in the engine, providing a metallic substrate, a metallic filler bonded onto a substrate bond surface on the metallic substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate beneath the substrate bond surface. One embodiment provides a laser shock peened surface below the weld material filled void in a damaged area of the component forming a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the component. Optionally, the surface over the repaired area of the weld filled void may also be laser shock peened forming a second region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the weld repair.

Abstract: A single-crystal article having a thermal barrier coating on a surface thereof, and a method for processing the article so as to promote the life of the coating. As a result of its single-crystal microstructure, the article is characterized by having been unidirectionally solidified along a primary crystallographic direction, and secondary crystallographic directions that are normal to the primary crystallographic direction. Improved spallation resistance of the coating is achieved by selectively orienting the secondary crystallographic direction with respect to a direction normal to a life-limiting surface region of the thermal barrier coating.

Abstract: A ceramic coated heat-resistant element comprises a heat resisting alloy base mainly composed of Ni and/or Co and a heat-resistant coating layer provided on the surface of the base and is characterized in that said heat-resistant coating layer comprises a metal layer of an alloy superior to the base in high-temperature corrosion and oxidation resistance and provided on the base, an Al.sub.2 O.sub.3 ceramic thin film layer provided on the metal layer, a ZrO.sub.2 ceramic coating layer having dense texture provided on the Al.sub.2 O.sub.3 ceramic thin film layer and a ZrO.sub.2 ceramic coating layer having columnar texture provided on the ZrO.sub.2 ceramic coating layer having dense texture cracks are present only in the ZrO.sub.2 ceramic coating layer having columnar texture in the direction of thickness along the boundary of the columns. A mixed layer composed of a metal superior to the base in high-temperature corrosion and oxidation resistance and a ZrO.sub.

Abstract: An environmental coating and a method for forming the coating on a nickel aluminide component designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The environmental coating includes a metal that has been diffused into the surface of the nickel aluminide component, and an aluminum oxide layer on the surface of the nickel aluminide component. According to this invention, the metal is one or more noble metals, chromium and/or an MCr alloy, and forms a diffusion region comprising noble metal-aluminides and/or chromium-aluminides. The environmental coating optionally contains up to about 1.0 atomic percent of at least one oxygen-active element, such as yttrium, hafnium, zirconium and/or cerium. According to the invention, the environmental coating need only consist of the diffusion region and the aluminum oxide layer, and therefore does not require additional environmentally-resistant layers (e.g.

Abstract: A turbine rotor comprising a radially-inward portion of a steel alloy and a radially-outward rim portion circumscribing the radially-inward portion, the rim portion being formed by a weldment that includes a nickel-base superalloy region joining the rim portion to the inward portion of the turbine rotor, the nickel-base superalloy having a room temperature ultimate tensile strength of at least about 690 MPa.

Abstract: An improved aluminide coating especially for heat resistant superalloy substrates. Slurry coating compositions of eutectic metal alloy powders and of non-eutectic metal powders. A process for coating the substrates and the coated metal parts. The coatings have improved resistance to developing cracks and to hot corrosion and oxidation.

Abstract: An article having a protective coating thereon includes a substrate having a substrate composition and a substrate surface, and a protective coating contacting and overlying at least a portion of the substrate surface. The substrate is preferably a Ti--Nb aluminide, an .alpha.2-titanium aluiminide, or a .gamma.-titanium aluminide. The protective coating includes a metallic layer contacting the substrate surface and having a composition, in atomic percent, of from about 5 to about 40 percent chromium, from about 44 to about 59 percent aluminum, balance titanium plus incidental impurities. The protective coating may further include a ceramic layer contacting and overlying the metallic layer, with the metallic layer lying between the ceramic layer and the substrate.

Abstract: A nickel-base superalloy, in particular for the fabrication of large monocrystalline components, essentially comprises (measured in wt %): 6.0-6.8% of Cr, 8.0-10.0% of Co, 0.5-0.7% of Mo, 6.2-6.6% of W, 2.7-3.2% of Re, 5.4-5.8% of Al, 0.6-1.2% of Ti, 6.3-7.0% of Ta, 0.15-0.3% of Hf, 0.02-0.04% of C, 40-100 ppm of B. 15-50 ppm of Mg, the remainder being nickel with impurities. Carbides of Ta, Ti, and Hf, and Mg, and/or Mg--O--S compounds are concentrated along small angle grain boundaries of the superalloy.

Abstract: A hollow article is made by providing and diffusion bonding the opposing parts of an article made of an alpha-beta titanium alloy. Hydrogen is introduced into the surface of an internal cavity before, during, or after diffusion bonding. The article is heat treated with the hydrogen present, typically by solution treating and aging the hydrogen-containing bonded article. The result is the production of a microstructure at the internal surface of the cavity that is resistant to fatigue-crack initiation, while retaining a microstructure throughout the rest of the article that is resistant to fatigue-crack propagation. After heat treating, the hydrogen Is removed from the article, and any further heat treating and other operations are completed.

Abstract: A steam turbine in which principal components to be exposed to high temperatures are all made of ferritic steel, whereby the temperatures of main steam and reheat steam can be increased to 610-660 (.degree.C.). The rotor shaft (23 in FIG. 1) of the steam turbine is made of ferritic forged steel whose 100,000-hour creep rupture strength is at least 15 (kg/mm.sup.2) at the service temperature of the rotor shaft. Likewise, the casing (18) is made of ferritic cast steel whose 100,000-hour creep rupture strength is at least 10 (kg/mm.sup.2). The steam turbine of high thermal efficiency can be applied to a steam-turbine power plant.

Abstract: A root attachment for a rotor blade of a gas turbine engine comprises teeth on the root section of the rotor blade and teeth on the slot of the rotor. The teeth flank surfaces of the teeth on the root section of the rotor blade are arranged at a different angle to the teeth flank surfaces of the teeth on the slot of the rotor. As the load on the rotor blade increases the teeth deflect such that the area of contact between the teeth flank surfaces of the root section and the slot increases to a maximum at the fully loaded condition. The teeth flank surfaces are substantially planar. This enables rotor blade and slot teeth with different stiffnesses to be used for the rotor blades and rotor, for example titanium aluminide turbine blades and nickel base alloy turbine rotor.

Abstract: A power generation gas turbine includes first stage turbine blades made of an alloy whose 10.sup.5 -hour 14-kgf/mm.sup.2 temperature capacity is 920.degree. C. or over, second and subsequent stage turbine blades made of an alloy whose 10.sup.5 -hour 14-kgf/mm.sup.2 temperature capacity is 800.degree. C. or over, first stage turbine nozzles made of an alloy whose 10.sup.5 -hour 6 kgf/mm.sup.2 temperature capacity is 900.degree. C. or over, and second and subsequent stage turbine nozzles made of an alloy whose 10.sup.5 -hour 6-kgf/mm.sup.2 temperature capacity is 800.degree. C. or over.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: In a method of investment casting a turbine nozzle which includes an outer band, an inner band and an airfoil section extending between the inner and outer bands, an improvement including shaping a temporary wax form, and external shell and internal core components used in casting such that during pouring of molten metal into a space created by removal of the wax form, shell material lies on opposite sides of an outer fillet connecting the outer band to the airfoil section. The resulting gas turbine nozzle includes first and second horizontally oriented ribs extending about interior peripheries of the airfoil section vertically adjacent the outer and inner band fillets.

Abstract: A coated superalloy component includes a substrate article formed of a superalloy and an adherent coating over the substrate. The coating is a nickel-base superalloy containing 0.3 volume percent or more of a dispersed oxide of yttrium, hafnium and/or a rare earth, and, preferably, grain boundary strengthening elements such as carbon, zirconium, and boron. The oxide dispersoids improve the performance of the coating in service, reducing the incidence failures due to thermal fatigue, oxidation, and corrosion damage. The dispersoid-containing coating may be formed by directly depositing the oxide-containing coating, or by depositing a metallic coating under conditions which permit the formation of such dispersoids during the deposition process.

Abstract: Steam turbine fluid directing components are improved in erosive wear resistance by application of either relatively tougher and relatively less hard thermal spray or relatively harder and relatively less tough diffusion alloy surface modification to different portions of the component as a function of the locally greater or locally smaller angle of attack of solid particles on those portions in the use condition of the component.

Abstract: The performance of many macroscopic structures (those whose dimensions are on the order of centimeters, meters, or even larger) can be greatly improved by covering their surfaces with microstuctures. There are several applications in which "large," microstructure-covered sheets are useful. For example, dissimilar sheets of material that otherwise would not bond well to one another (such as a polymer and a metal) can be more strongly bonded with microstructures extending from one of the sheets and embedded into the other sheet. Such products make valuable laminate composites. As another example, the rate of heat transfer between an object and the surrounding medium can be dramatically changed (up or down) by covering the surface of the object with high aspect ratio microstructures, without significantly changing the component's size or weight.

Abstract: The invention relates to a titanium article of manufacture having an oxidation resistant surface and a process for producing such article wherein said titanium has an aluminized surface layer formed on it by the vapor deposition of aluminum on the titanium followed by oxidizing the surface layer.

Abstract: An airfoil blade, such as a jet engine turbine rotor blade. An internal serpentine coolant circuit has a last downstream passageway bounded by four monolithic inner walls which are monolithic with at least a portion of the outer walls. Two of the inner walls are spaced from the outer walls and contain air impingement orifices creating two impingement chambers. Some coolant in the serpentine circuit exits the airfoil blade through a coolant exit in the blade tip. The remaining coolant in the circuit passes through the impingement orifices and exits the blade through film cooling holes in the outer walls.

Abstract: The surface of an aluminide is treated to make it less chemically reactive. In particular, this treatment inhibits oxidation of the aluminide at high temperatures. According to the invention, one coats the aluminide with a solution that containing phosphoric or phosphorous acid, and then one heats the aluminide, so as to calcine the coating. The phosphoric or phosphorous acid reacts with the aluminide to form a surface that resists oxidation. One can use this process to coat the blades of a gas turbine, or to coat other aluminide structures intended for use in high-temperature environments.

Abstract: A turbine engine blade made from a composite material and having at a free end thereof an integrated brush joint. A process for producing such a blade includes the steps of:introducing a fibrous fabric into a mold,introducing specific fibres into the mold, in the vicinity of the free end of the blade,injecting a resin into the mold,performing polymerization by use of a heating press of the resin-impregnated fibrous fabric.

Abstract: A double-wall airfoil for applications such as the blades and vanes of gas turbine engines. The double-wall comprises an outer airfoil skin and an inner support wall that are metallurgically bonded to one another. The double-wall contains integral channels for passage of cooling air adjacent to the airfoil skin. Airfoil skin may be a metal alloy skin or a microlaminate structure, including microlaminate composite structures. Microlaminate composites typically have a lower density than that of the material used for the airfoil support wall, and a simplified internal geometry which promote weight reductions in the airfoils and increases in engine operating efficiency.

Abstract: The present invention relates to a steam turbine comprising a rotor shaft integrating high and low pressure portions provided with blades at the final stage thereof having a length not less than 30 inches, wherein a steam temperature at first stage blades is 530.degree. C., a ratio (L/D) of a length (L) defined between bearings of the rotor shaft to a diameter (D) measured between the terminal ends of final stage blades is 1.4 to 2.3. This rotor shaft is composed of heat resisting steel containing by weight 0.15 to 0.4 % C, not more than 0.1 % Si, 0.05 to 0.25 % Mn, 1.5 to 2.5 % Ni, 0.8 to 2.5 % Cr, 0.8 to 2.5 % Mo and 0.15 to 0.35 % V and, further, the heat resisting steel may contain at least one of Nb, Ta, W, Ti, Al, Zr, B, Ca, and rare earth elements.

Abstract: Gas turbine engine blade with a metallic airfoil having a radially outer tip extending chordwise between a leading edge and a trailing edge and at least one laser shock peened surface extending radially along at least a portion of the tip and a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.

Abstract: A heavy-duty gas turbine includes a compressor; a combustion liner; a turbine blade in a single stage or multi-stages; and a turbine nozzle provided in correspondence to the turbine blade. The turbine blade has a dovetail secured to a turbine disk and has an overall length of not less than 180 mm, and it is made of a single-crystal Ni-base alloy whose .gamma. phase is a single crystal. Operating gas temperature is not less than 1400.degree. C., and metal temperature of a first blade is not less than 1000.degree. C. under working stress.

Abstract: A gas-turbine moving blade made of a Ni-base superalloy containing less grain boundary strengthening elements, in which a blade portion is formed of a single crystal and the rest is formed of columnar crystals, and a gas turbine including the moving blade. A thermal efficiency of the gas turbine can be improved to 35% or more, and a thermal efficiency of complex power generation with a steam turbine can be improved to 45% or more.

Abstract: A high pressure-low pressure single cylinder turbine rotor is disclosed which is characterized by being formed of a steel of a composition having, by weight, a C content of from 0.10 to 0.35%, a Si (silicon) content of not more than 0.3% (not including 0%), a Mn (manganese) content of not more than 1.0% (not including 0%), a Ni content of from 1.0 to 2.0%, a Cr (chromium) content of from 1.5 to 3.0%, a Mo content of from 0.9 to 1.3%, a V (vanadium) content of from 0.10 to 0.35%, a Nb (niobium) content of from 0.01 to 0.15%, a W content of from 0.1 to 1.5%, and the balance of Fe (iron) and inevitable impurities, the inevitable impurities having a P content of not more than 0.005%, a S content of not more than 0.001%, an As content of not more than 0.008%, a Sb content of not more than 0.004%, and a Sn content of not more than 0.008%.

Abstract: High toughness stainless steel type 13Cr5Ni containing C: 0.008-0.03% (by weight, all of the following elements), Si: max. 1%, Mn: max. 2%, Cr: 10.0-14.0%, Ni: 4.0-7.0%, and Mo: 0.2-2.0%, in which (Cr/Ni) ratio is in a range of 2.0-3.0 or (C/Mo) ratio is in a range of 0.015-0.1, as a structural material for fluid machinery, austenitic stainless steel containing C: 0.10-0.30% (by weight, all of the following elements), Si: max. 1%, Mn: max. 2%, Cr: 16.00-23.00%, Ni: 1.00-8.00%, and Co: 2.00-9.00%, and Ni+Co: 6.00-12.00% as a weld padding layer forming material, and fluid machinery using the same.

Abstract: A cobalt based coating is provided which is functional to reduce the coefficient of friction between two operatively, frictionally engaging titanium alloy surfaces.

Abstract: An air moving device such as an axial cooling fan comprises a rotatable shaft assembly and a plurality of fan blades coupled to the rotatable shaft assembly, each of the fan blades having a trailing edge when the rotatable shaft assembly is rotated in a given direction. In accordance with one illustrative embodiment of the invention, at least one of the fan blades has a sound reducing material attached thereto alongside the trailing edge thereof. The sound reducing material reduces aeroacoustic noise by reducing the aerodynamic effect that occurs when turbulence produced by the pressure differential between the two sides of one blade comes into contact either with the trailing edge of the given blade which created it, or, more significantly, with the following blade, at or near that blade's trailing edge.

Abstract: Steam or gas turbine components comprising chromium steel have their fluid directing surfaces protected from corrosion by a surface layer coating consisting essentially of major weight amount of nickel and minor weight amounts of zinc, optionally with boron added, over a nickel preplate which limits deleterious diffusion of zinc into the surface substrate.

Abstract: Gas turbine engine fan blade with a metallic airfoil having a leading edge, a trailing edge, and a radially outer tip, and at least one laser shock peened surface located along the leading edge with a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.

Abstract: A family of environmentally-resistant alloys is provided which are suitable for forming a blade tip for a turbine blade of a gas turbine engine. The blade tip alloys preferably have a chemical composition of, in weight percent, about 14 to about 18 percent chromium, about 6.45 to about 6.95 percent aluminum, about 9.75 to about 11.45 percent cobalt, about 5.95 to about 6.55 percent tantalum, about 1.85 to about 2.35 percent rhenium, about 0.05 to about 1.75 percent hafnium, about 0.006 to about 0.03 percent zirconium, about 0.02 to about 0.11 percent carbon, up to about 1.1 percent silicon, up to about percent 0.01 percent boron, with the balance being nickel and typical impurities.

Abstract: A wide gap braze repair, particularly for a gas turbine engine vane or a component in the hot section of the engine. The repair is characterized by a braze filled void in a damaged area of the component, a laser shock peened surface over the repaired area of the braze filled void, and a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the repair.

Abstract: A high strength, forged monolithic shrouded impeller is made from a single forged blank by a method that includes the following four steps: Turning and boring a rough forging to an impeller profile; using a three-dimensional CNC milling machine with end mills, removing as much material as possible from what are to be passageways in the impeller, defining leading and trailing edge zones of vanes defining the passageways by removing material in direct line of sight from the outside diameter or from the eye of the impeller or both; forming a hole through a central zone of what will be each impeller passageway, and removing the remainder of the material to define the passageways by three-dimensional planing controlled by the CNC machine.

Abstract: A composite weld wire, for use in repairing an article of a Co base alloy, comprises the sintered product of a mixture, by weight, of about 50-90% of the Co base alloy and about 10-50% of a Ni base alloy consisting essentially of, by weight, about: 1.5-2.5% B, 2-5% Al, 2-4% Ta, 14-17% Cr, 8-12% Co, with the balance Ni and incidental impurities. Conveniently, the alloys initially are in powder form. A repaired Co base alloy article including a surface discontinuity, such as a crack or void, comprises a welded repair at the discontinuity using the weld wire. In another form, the article includes a first diffusion bonded repair alloy at the discontinuity and a second repair alloy welded over the first repair alloy using the composite weld wire. One form of a method for repairing the article includes first removing oxides from the discontinuity, diffusion bonding the first repair alloy at the discontinuity, and then welding the second repair alloy over the first repair alloy using the composite weld wire.

Abstract: A component made of an intermetallic compound of titanium and aluminum, or of alloys of such intermetallic compounds with alloying additions forming the base material, and with an aluminum diffusion coating on the base material, is provided. The component has, between the base material and the aluminum diffusion coating, a closed zone which is close to the surface and has a recrystallization structure. For this purpose, the component is cold-formed or slightly melted in a zone which is close to the surface, is then annealed at the recrystallization temperature, and finally has an aluminum diffusion coating applied to the recrystallized zone. The process is used for components in engines and, particularly, for components in the hot-gas duct of an engine.

Abstract: A method of making an integrally bladed disc for a gas turbine engine, the disc having at least one blade the radially outermost surface of which is coated with a material harder than that of the blade, the method comprising the steps of: providing a forged disk blank of a first material; friction surfacing at least part of the circumference of the blank with a second material harder than the first material; and machining the blank so as to provide an integrally balded disc wherein the radially outermost surface of at least one blade is coated with said second material.

Abstract: An improved abrasive blade tip for gas turbine engines is taught, wherein an abrasive tip coating is applied to the blade tip in such a manner as to lessen wear through of the abrasive and the underlying airfoil on the leading and trailing edges, by coating the blade tip with abrasive not only on the tip surface per se, but so as to cover portions of the convex and concave airfoil surfaces at the corners where the tip surface intersects the leading and trailing edges.