Abstract: A gas turbine vane (1) is subject to distortion and wear during operation or repair which results in an increase in the spacing between successive vanes (6 and 7) which define nozzle gas flow areas (8 and 9). During refurbishment, the nozzle spacing must be returned to the original dimension to insure optimum turbine performance. A build up of alloy in the wear area is accomplished by controllably applying layers of a tape (12) of uniform thickness to the vane. The tape includes a mixture of a binder and an alloy powder, which is compatible with the substrate alloy, with the mixture formed into a sheet of uniform thickness and having an adhesive backing. After applying the tape in layers to a desired thickness, the vane is heated to a temperature at which the binder and adhesive decompose and the alloy in the tape diffusion bonds with the substrate alloy. Utilization of this process reduces the cost of refurbishing used turbine vanes and avoids hot forming or bending processes which could damage the vanes.

Abstract: A single crystal nickel alloy is provided having many of the foundry and performance characteristics of the higher density, single crystal, nickel base super alloys from which the vanes and blades are cast for high performance turbine aircraft engines. The lower density of this alloy permits its use for rebuilding and upgrading the performance of older turbine aircraft engines of designs which cannot withstand the centrifugal forces generated by the new state of the art higher density single crystal super alloys. The alloy for the first time provides a lower density single crystal alloy capable of heat treatment to stabilize its microstructure for high temperature, high stress use. It also provides for the first time a lower density alloy having acceptable resistance to the effects of high temperature sulfidation, salt corrosion and also to have good coating life.

Abstract: An oxidation resistant alloy comprising about 3 to 14 percent Cr by weight, about 3 to 50 percent by volume Si.sub.3 N.sub.4, and the balance selected from the group consisting of Fe, Ni, Co and alloys of these metals. Preferably, the Cr content is between 8 to 12 percent by weight, the Si.sub.3 N.sub.4 content is between about 3 to 22 percent by volume, and the alloy further includes between 1 to 2 percent Si by weight and between about 0.05 and 0.2 percent by weight of a reactive element.

Abstract: Steam turbine blades are fastened in an outer layer of weld material applied by deposit welding to the outer surface of the rotor body, the composition of the weld material being optimally matched with respect to hot strength and/or corrosion resistance, in particular stress corrosion resistance, to the local mechanical, thermal and chemical requirements. A possible option is additionally to insert a deposit welded intermediate layer of medium alloying element content. Steels with 10-14% Cr, low carbon and additions of Mo and possibly V are preferred as the weld material for the layer.

Abstract: A compressor wheel assembly for turbochargers and the like comprises a compressor wheel including a boreless hub formed integrally as by casting with a circumferential array of aerodynamically contoured centrifugal impeller blades. The wheel hub is secured at its base by inertia welding to a thrust spacer sleeve having an internally threaded bore for threaded reception of a rotatable shaft. In use of the compressor wheel assembly, the absence of a bore within the wheel hub substantially improves wheel fatigue life.

Abstract: A method for the manufacture of a guide blade for a turbine or compressor guide wheel, uses a profiled bar of heat and corrosion resistant metal that is cut to oversize length. This is in preparation for soldering the bar into a guide wheel, with the bar having at least at one end a baselike thickening which is upset in a cold state, and with a soldering surface formed in its inner zone.

Abstract: A dual alloy radial turbine rotor with high tensile strength hub material exposed in the saddle regions between the blades to prevent fatigue that causes cracks in the saddle regions is manufactured by producing the hub with additional material at the outer portions of a frustoconical rear portion of the hub. After diffusion bonding of the outer surface of the hub to the mating inner surface of the blade rim, portions of the blade rim in the saddle regions are machined away to produce finished saddle configurations with the high tensile strength hub material exposed.

Abstract: What is disclosed is a multi-hubbed, separable blade agitator assembly wherein the exterior surfaces of the hubs of each agitator blade as well as the exterior surface of the drive shaft are coated with glass and the hubs are interference fitted to the drive shaft in glass-to-glass surface contact sufficient to withstand torque imparted to the agitator blades by the drive shaft.

Abstract: The present invention provides a method for constructing from fiber-composite material complex structures having two or more transversely disposed members. By way of example, a composite turbine blade 10 having an aerofoil 12 and an integrally formed footing 14 can be constructed using this new method, which method comprises the steps of forming from fiber-composite monotape a blank 40 in the general shape of aerofoil 12 with the fibers 18' of the monotape being oriented in a generally spanwise direction, exposing the fibers 18' at the root 42 of the aerofoil blank 40, inserting transversely between the exposed fibers 18' a plurality of foot-forming monotapes 17 to form a transversely meshed, tape and fiber structure 68, filling the voids in the transversely meshed structure with powdered matrix material and hot-pressing the filled-in structure 70 substantially according to the desired final shape of the fiber-composite turbine blade.

Abstract: A heat resistance structure adapted to be used in a passage of a high temperature fluid, comprises a heat resistant metal plate having a smooth outer surface, a layer of a substance having a high heat transmission resistance extended along an internal surface of the metal plate, and heat conductive bodies provided in close contact with the layer, all being arranged in this order from the outer surface of the structure to the interior of the structure. A plurality of coolant passages are further provided through each of the heat conductive bodies.

Abstract: An object is manufactured from a powdered material by isostatic pressing of a body, preformed from the powdered material, with a pressure medium, whereby the preformed body, in which at least the surface layer consists of a ceramic material in the form of a nitride, is surrounded by a casing which is rendered impenetrable to the pressure medium, before the isostatic pressing is carried out and the powder sintered. As the material in the casing there is used boron oxide or a glass containing boron oxide or a material forming glass while being heated, in which the content of boron oxide is sufficiently high for the glass--or the glass formed during heating--to be removable by water. The preformed body surrounded by the casing is subjected to a heat treatment for the formation of boron nitride on the surface of the preformed body, before the isostatic pressing is carried out. The casing is removed from the finished product by means of water or water vapor.

Abstract: The inlet and/or outlet edge of a blank which is to be converted into the vane of an impeller for use in a centrifugal pump is reinforced by providing an exposed surface of the blank with a pair of contiguous recesses which extend along the edge and the deeper of which is immediately adjacent to the edge. The recesses are then filled with metallic armoring material by cladding so that some of the surplus extends beyond the recesses and/or beyond the edge. In the next step, the surplus of armoring material is removed by one or more material removing tools, together with a portion of the blank in the region of the edge so that the exposed surface is provided with a fresh edge which is defined by the armoring material.

Abstract: Stress relief for the rim of an integrally bladed rotor made from a forging preform is provided by forming a plurality of radially extending circumferentially spaced-apart slots around the periphery of the preform. The slots are forged closed in a subsequent forming step. An oxide layer on the slot surfaces prevents the surfaces from bonding together when forged closed. The blades are formed between slots during the forging or by machining after forging.

Abstract: A single crystal nickel base superalloy component, such as a gas turbine blade (20, 28) is mechanically deformed at elevated temperature to improve the yield strength of a portion which is used at temperatures below 800.degree. C., compared to a portion which is used at a higher temperature. A blade (20) has a root (22) which is deformed by 2-14% at 700.degree.-1100.degree. C. and an airfoil (24) which is not deformed. The root yield strength is increased 15-50% while the airfoil creep strength is maintained.

Abstract: A heated ceiling fan comprising a plurality of blades with heating means in each of the blades.

Abstract: A coolable rotor blade 14 for an axial flow rotary machine and a method for making the rotor blade are disclosed. The rotor blade includes a spar 38 and a shell 34 for defining the airfoil surface of the rotor blade. A platform 36 extends over the shell and the spar. The spar has a root 42 and an airfoil section 40. The shell is spaced from the spar and is joined to the airfoil section of the spar for defining cooling passages in the blade. The shell and the platform are each attached to the spar for support against rotational force. The method includes the steps of joining a shell to the airfoil section of the spar which extends over a portion of a projection 139 on the spar and forming a platform about the spar and the shell such that the platform is attached to the spar and extends over the projection and a portion of the shell. In one embodiment, the spar is formed of a first material, the shell of a second material, and the platform a third material.

Abstract: A welded structural member adapted to be subjected to a flowing fluid and comprising a base member consisting mainly of iron and a coating layer formed by a build-up welding on the surface of the base member, the coating layer having a higher erosion resistance than the base member. The coating layer contains 0.03 to 0.4 wt % of C, 0.1 to 1 wt % of Si, 0.5 to 20 wt % of Mn, 1 to 5.5 wt %, of Ni, 1 to 12 wt % of Co, 8 to 23 wt % of Cr and the balance Fe. The structure of the coating layer is mainly unstable austenite.

Abstract: A blade for a fluid flow engine, especially a gas turbine, has a protective coating against injurious attack by the propellant or working medium. A metal blade having a diffusion layer or a sprayed coating for inhibiting corrosion is known. Such coating renders the blade highly resistant against heavily erosive and corrosive attack, especially by pulverized coal combustion gas or similar agents. The present blade is made of ceramic material, especially a dense ceramic material with a surface layer of at least one of the following materials: TiN, TiC, B.sub.4 C, BN and titanium carbon nitride. These materials are easy to apply and provide a good bond with the ceramic material. If the ceramic materials are silicon carbide (SiC) or silicon nitride (Si.sub.3 N.sub.4) an especially good bond is achieved. This coating strongly resists removal, as it does oxidation and heat. Local removal down to the ceramic material, as it may result from rather long service, is recognizable immediately.

Abstract: The invention is concerned with the problem of joining ceramic components to metal components.A composite ceramic-metal component is proposed, e.g. a rotor disc for a gas turbine engine (see FIG. 2), in which the main body of the component is made from a ceramic, e.g. Silicon Nitride, but the areas at which attachment is to be made to a metal component is formed from metal compacted onto the ceramic by a hot isostatic pressing process.The method of manufacture described is to form a ceramic core with holes appropriately positioned in it where a connection is to be made to another component, surround the core with a powdered metal, e.g. a Nickel-based superalloy, ensuring that the holes also fill with powder, compacting the powder by hot isostatic pressing, and then machining away unwanted metal.

Abstract: An integrally bladed bimetallic rotor for high temperature operation having airfoils with good stress rupture and creep strength and a hub with high tensile strength and good low cycle fatigue resistance is made from a preform of two concentric cylinders of different superalloy metals metallurgically bonded to each other at their interface, both materials being in such a condition that they exhibit superplastic behavior at a certain, controlled strain rate and temperature without incurring substantial grain growth. The metal of the outer cylinder is selected such that it has a lower gamma prime solvus temperature than the metal of the inner cylinder. The preform is isothermally forged at the controlled strain rate and temperature to form the airfoils from the alloy of the outer cylinder and to form the hub from the alloy of the inner cylinder. A sharp, reproducible interface is created between the two alloys.

Abstract: The present invention relates to turbine blades and in particular to turbine blades for use in gas turbine engines. Tensile stresses are introduced into turbine blades when they rotate at high speeds on a turbine rotor. In order to minimize the stresses in an outer skin of an aerofoil of the turbine blade, the outer skin is secured to a platform and an inner core, and in operation a temperature difference is set up between the outer skin and the inner core. The temperature difference produces a thermal compressive stress in the outer skin which opposes the tensile stress produced due to the rotation of the turbine blade. The extremities of the outer skin may be secured to the platform with either a tensile or compressive prestress depending upon the temperature difference between the outer skin and inner core at normal operating conditions.

Abstract: Gas turbine engine superalloy airfoils and other components having unique microstructures and novel combinations of physical properties are produced rapidly and economically by the method of the invention which uses the low pressure/high velocity plasma spray-casting process and segmented mandrels.

Abstract: A substrate, such as a turbine blade, vane, or the like, which is subjected to high temperature use is coated with a base coating of an oxide dispersed, metallic alloy (cermet). A top coating of an oxidation, hot corrosion, erosion resistant alloy of nickel, cobalt, or iron is then deposited on the base coating. A heat treatment is used to improve the bonding. The base coating serves as an inhibitor to interdiffusion between the protective top coating and the substrate. Otherwise, the protective top coating would rapidly interact detrimentally with the substrate and degrade by spalling of the protective oxides formed on the outer surface at elevated temperatures.

Abstract: A cast metal turbine wheel is made comprising a cylindrical disc with equiaxed grains and integral blades with columnar grains oriented substantially parallel to the leading and trailing blade edges. The blades are solidified unidirectionally by withdrawing heat through chill means located adjacent the mold at the blade tips. Cooling is inhibited from other blade surfaces by retaining cast metal in mold portions located above and below the blades. The disc portion of the mold is insulated so that it cools slowly to promote grain nucleation throughout the metal therein and equiaxed grain growth.

Abstract: Titanium and titanium alloy particles are provided with improved mechanical properties through the use of ion implantation. Ions of elements selected from the noble metals and titanium are employed. Ion energies of 50-200 kev and ion densities of at least 10.sup.14 ions/sq. cm. are employed.

Abstract: A heat resistant machine component, e.g. a gas turbine blade, a vane or the like, for use in a hot-gas atmosphere, especially under dynamic mechanical strain. The engine component comprises a core body consisting of a heat resistant material and a surface layer sprayed thereon and constituted by a composite material. The composite material consists on the one hand of an alloy component containing 1 to 12% Al, namely preferably 3 to 8% Al, 10 to 30% Cr, small quantities of one or more elements in the group Si, Mn, Co, Y and Hf, and the balance Fe, and on the other hand a small quantity of an oxide component containing Al.sub.2 O.sub.3 and possibly one or more oxides of the remaining metals of the alloy component, wherein the pores and the oxide component form elongated, narrow regions, which partly surround or cover the alloy component. The surface layer is applied by flame or arc spraying under a controlled minor oxidation.

Abstract: Shot peening of thin edges of workpieces which are subject to deformation damage by direct impacts is accomplished by rotating the workpiece edge near centerline through a particular angle measured from the normal to the shot streamline. The angle is sufficient to cause oblique blows on the centerline of the edge, but insufficient to cause direct impacts. Compressive stresses by the oblique blows provide residual compressive stresses along the centerline to the desired depth. The angle is calcuable from the edge radius, the depth of stressing desired at the centerline, and the depth of stressing produced by shot at a reference location. Oscillatory rotation is preferably used to obtain even peening.

Abstract: Gas turbine engine superalloy airfoils and other components made by low pressure/high velocity plasma spray-casting have unique microstructures and, consequently, novel combinations of physical properties superior to those of components of the same alloy compositions made by conventional methods.

Abstract: In the method for fabrication of water-cooled composite nozzle and bucket hardware for high temperature gas turbines, a high thermal conductivity copper alloy is applied, employing a high velocity/low pressure (HV/LP) plasma arc spraying process, to an assembly comprising a structural framework of copper alloy or a nickel-based super alloy, or combination of the two, and overlying cooling tubes. The copper alloy is plamsa sprayed to a coating thickness sufficient to completely cover the cooling tubes, and to allow for machining back of the copper alloy to create a smooth surface having a thickness of from 0.010 inch (0.254 mm) to 0.150 inch (3.18 mm) or more. The layer of copper applied by the plasma spraying has no continuous porosity, and advantageously may readily be employed to sustain a pressure differential during hot isostatic pressing (HIP) bonding of the overall structure to enhance bonding by solid state diffusion between the component parts of the structure.

Abstract: A bucket for an adjustable turbine guide baffle system for gas turbines is formed of an alloy material comprised of a dispersion-strengthened Fe-Cr-Al alloy containing 64.5-75.5% by weight of Fe, 15-25% by weight of Cr, 3-8% by weight of Al, 0.1-1% by weight of Ti, 0-3% by weight of Co, 0.1% by weight of Y or Ce, and 0.1-1.5% by weight of yttrium oxide or aluminum oxide. The bucket has a shank which is under friction stress in the guide baffle system and which is coated with a layer of slip-providing material that contains 90-100% by weight of nickel oxide and 0-10% by weight of one or more oxides of chromium, aluminum, zirconium, titanium, iron, manganese, or magnesium.

Abstract: A separable blade agitator having the impeller blades joined to the drive shaft in an interference fit effected by a hub on one of the separable impellers which embraces both the shaft and the other impeller.

Abstract: A hybrid dual property radial turbine rotor for a gas turbine engine includes an airfoil shell having a plurality of radially outwardly directed airfoils thereon joined to a continuously circumferentially formed inner periphery including a constant diameter axially extending portion and a radially outwardly flared skirt portion thereon into which is fitted a preformed hub plug of dense stress resistant material having an axially extending nose portion thereon with a controlled constant circumference surface throughout its length of a precision dimensioned diameter and further including a conical end thereon with a surface thereon of a slope that is congruent with the slope of the flared skirt portion of the cast metal rotor shell and wherein the slope of the flared skirt portion is configured to optimize the location of the high strength hub material and to achieve optimum blade and hub stress levels.

Abstract: A considerable increase of the life time of metallic members, particularly the blades of fans or turbines, which are exposed to air-borne abrasive particles is obtained by providing such members with a wear-resisting attachment comprising at least two wear-resisting layers consisting of materials having complementary relationships of the erosion caused by said abrasive particles to the impact angle of the particles, said attachment being applied to surface portions of the members to be protected.

Abstract: A composite shaped article comprising at least one reinforcing core of a heat-resistant oxide-dispersion-hardened metal or alloy and a cladding of a heat-resistant metal or alloy which is compatible with the core material, the core being wholly encapsulated within and bonded to the cladding material.A method for making the articles is provided.

Abstract: A blade or vane for a gas turbine has a cambered aerofoil made up of a plurality of single crystals of an alloy. Each crystal extends longitudinally of the aerofoil and has a predetermined three-dimensional orientation different from that of the other crystals such that it has an optimum value of a chosen property in directions longitudinal and transverse of the aerofoil.

Abstract: A high-speed rotor constructed of elemental boron and fashioned as a hollow element such as a centrifugal drum.

Abstract: Disclosed is an improved abrasive material particularly useful as a dispersoid in metal matrices to provide articles of use having superior abrasive properties, especially at elevated temperatures. The improved abrasive material typically comprises silicon carbide particulate, the individual particles of which have a predominantly alumina coating thereon to inhibit dissolution of the particles in the metal matrix at high temperatures. The invention finds special application in abrasive blade tips for service in gas turbine engines, the tips comprising a nickel base or cobalt base superalloy having the alumina coated silicon carbide particles dispersed therein.

Abstract: A turbomachinery blade including a hollow interior is provided with an improved tip cap comprising first and second members each made of an alloy of a composition and properties different from the other. The first member, in the form of a closure plate bonded to sidewalls of the hollow body, is of a nickel-base or cobalt-base superalloy casting characterized by high mechanical strength properties at elevated temperatures. The second member is a rib of the shape of and bonded to the first member and is of a cast alloy characterized by the combination of resistance to oxidation, sulfidation and thermal fatigue at elevated temperatures. The second member provides an outer tip extension of the blade.

Abstract: A cast metal turbine wheel is made comprising a cylindrical disc with equiaxed grains and integral blades with columnar grains oriented substantially parallel to the leading and trailing blade edges. The blades are solidified unidirectionally by withdrawing heat through chill means located adjacent the mold at the blade tips. Cooling is inhibited from other blade surfaces by retaining cast metal in mold portions located above and below the blades. The disc portion of the mold is insulated so that it cools slowly to promote grain nucleation throughout the metal therein and equiaxed grain growth.

Abstract: A rotor blade is manufactured by making a soft alloy into a blade body with a curved section, joining a hard alloy to the leading edge of the blade body, coating the back side surfaces of the leading and trailing edge portions of the blade by alternately giving at least one coat each of a Ni-Cr-B-Si alloy and WC by spraying and fusing the coats onto the backing surfaces, and then coating the entire front side surface of the blade in the same way.

Abstract: An improved gas seal between a stationary member and a movable member, one of which includes an abrasive tipped projection directed toward a surface of the other, for example a turbine engine blade and a cooperating shroud member, is provided through an improvement in the abrasive tip. Such improved tip of the projection is a composite of inner and outer tip portions, the inner portion comprising an alloy resistant to oxidation, sulfidation and thermal fatigue at operating temperatures and the outer tip portion comprising a matrix entrapping a plurality of abrasive particles which protrude from the matrix toward the surface of the other member. The inner tip portion is bonded with the metallic body of the projection and the outer tip portion is deposited on the inner tip portion.

Abstract: Method for vacuum depositing corrosion and oxidation resistant alloy coatings on turbine buckets having leading edges and trailing edges, with simultaneous rotation of the turbine buckets about their longitudinal axis in a vapor stream above a vapor source. The time of stay of each element of the surface above the vapor source is varied during a 360.degree. rotation such that it is shortest when the leading edges and the trailing edges are pointed towards the vapor source and longest when the concave and convex flanks are presented to it.

Abstract: This invention concerns a method for controlling the microstructure of directionally solidified eutectic articles and the article produced thereby. The method is particularly appropriate for the production of articles such as turbine blades which require different mechanical properties in different areas of the article. The microstructure is controlled by varying the directional solidification conditions during the casting process.

Abstract: A method for controlling the first torsional node line position in a rotatable blade of a turbomachine to improve its flutter stability including the steps of forming a first monolithic blade having a desired airfoil shape with convex and concave side walls; arranging several of the monolithic blades in a cascade array and subjecting the cascade array to an unsteady, supersonic, transonic and subsonic flow condition thereacross and thereafter determining the unsteady surface pressures acting on the monolithic blades; independently determining the first torsional mode vibration node line of each of the monolithic blades and comparing the resultant unsteady pressure force on the monolithic blades and its relationship to the first torsional mode vibration node line to determine whether or not the monolithic blade is absorbing or adding energy to the air flow thereacross; thereafter forming a plurality of first and thereafter modified composite blades by adding dissimilar material to the blade shape of a monolith

Abstract: Foil, wire and similar coherent bodies of catalytic metal are provided with catalytically active surfaces by diffusing a chemically removable metal such as aluminum or zinc into those surfaces and then selectively dissolving out at least about a third of the removable metal. Platinum wire screens activated in this way make effective exhaust catalysts for automotive engines.

Abstract: A method of refurbishing vane or blade components. Used turbine vanes or blades are cleaned, annealed and in some cases slotted adjacent their ends, after which any cooling passages (in the case of vanes) are welded closed and all cracks welded over, on both leading and trailing edges. The trailing edge, for a vane or blade component having a short chord, is built up by welding along its full length with an alloy wire, after which any slots that were cut adjacent the ends are closed, also by welding. Then the worn surfaces of the vane or blade are built-up by a plasma spray process, using a metal powder with added silica, to a thickness which can be as great as 30 to 40 thousandths of an inch. The built-up vane or blade is then sintered and thereafter surface finished to conform to the original contour of the component when new. Any cooling holes are finally recut, and the vane or blade polished as required and inspected.

Abstract: A method is provided for fabricating complex composite components for water-cooled, high temperature gas turbines. Each component comprises a core, a thermally conducting layer of copper bonded to the core, metal tubing through which water may pass embedded in and bonded to the layer, and a corrosion resistant cladding. The method utilizes powder metallurgy techniques to form the thermally conducting layer and hot isostatic pressure to bond the corrosion resistant cladding spar and tubes to said layer.

Abstract: To remove pollutants in the exhaust gases from a liquid fuel driven engine, a turbosupercharger, including a turbine and a compressor, is combined with the engine to provide both afterburning and catalytic oxidation. The exhaust gases are accumulated to provide combustion in advance of the turbine. Further, air is branched off from the compressor and mixed with the gases flowing through the turbine to afford combustion of the gases after they pass through the turbine. Catalytically active surfaces are located within the turbine for the reduction of nitric oxides.

Abstract: A refurbished turbine vane or blade. Used turbine vanes and blades are cleaned, annealed and in some cases slotted adjacent their ends, after which any cooling passages are welded closed and all cracks welded over, on both leading and trailing edges. The trailing edge, for a vane or blade having a short chord, is built up by welding along its full length with an alloy wire, after which any slots that were cut adjacent the ends are closed, also by welding. Then the worn surfaces of the vane or blade are built-up by a plasma spray process, using a metal powder with added silica, to a thickness as great as 30 to 40 thousandths of an inch. The built-up vane or blade is then sintered and thereafter surface finished to conform to the original contour of the component when new. Any cooling holes are finally recut, and the vane or blade polished as required and inspected.

Abstract: Foil, wire and similar coherent bodies of catalytic metal are provided with catalytically active surfaces by diffusing a chemically removable metal such as aluminum or zinc into those surfaces and then selectively dissolving out at least about a third of the removable metal. Platinum wire screens activated in this way make effective exhaust catalysts for automotive engines.