Abstract: A one piece, welded drum rotor for a gas turbine engine is described. The drum rotor is characterized by disks having a superalloy composition which is different from the seal alloy composition. Several welding techniques are utilized to join the drum rotor components to each other.

Abstract: Ceramic particles useful as abrasives in a metal matrix layer are described. The particles are coated with an oxide monolayer and a metal duplex layer. Preferably, the particles are silicon carbide; the oxide monolayer is aluminum oxide, and the metal duplex layer is a nickel-boron alloy over pure nickel.

Abstract: A mask particularly useful in the weld repair of air cooled gas turbine blades and vanes contains a mixture of ceramic particles in a liquid carrier. The mask is applied onto the surface of the blade or vane, and into the cooling holes. Following a sintering treatment, an inert, thermally stable, electrically nonconductive ceramic mask is produced, which is easily removed after welding.

Abstract: A filler metal material particularly suited for brazing titanium base articles is described. In a preferred embodiment, the material is characterized by a central portion of titanium, and adjacent layers of copper and nickel. The solidus and liquidus temperatures of the filler metal are about 925.degree. and 945.degree. C., respectively.

Abstract: Methods for heat treating cast, nickel base superalloy articles are described. According to the invention, the articles are heated to progressively higher temperatures greater than the gamma prime solvus temperature and less than the incipient melting temperature. The incipient melting temperature is increased due to homogenization of segregate phases, while at the same time, the gamma prime goes into solution. The rate at which the temperature is increased closely approximates the rate at which the incipient melting temperature increases due to homogenization.

Abstract: The high temperature strength to density ratio of titanium aluminum niobium alloys of the Ti.sub.3 Al (alpha two) type is increased when molybdenum is added. New alloys contain by atomic percent 25-27 aluminum, 11-16 (niobium+molybdenum), 1-4 molybdenum, balance titanium. When vanadium replaces up to 3.5% molybdenum a lighter weight alloy is produced. The new alloys have higher elastic modulus and higher creep strength to density ratio than alloys without molybdenum.

Abstract: A heat treatment is described for producing a desired microstructure in Hastelloy Alloy X components which have small diameter, closely spaced, laser pierced holes therein. The heat treatment produces a small grain size and discontinuous carbide morphology in the component prior to the hole piercing operation, which reduces the propensity for cracking which has been found to be associated with the hole piercing operation. After the piercing operation, the component is heat treated again to increase the grain size and produce a microstructure which provides the optimum balance of creep strength and fatigue strength.

Abstract: An apparatus and method are described for simultaneously thermal spraying at least two types of powders onto a substrate, wherein both powder types are carried by a single spray stream and impacted upon the substrate. According to the invention, the different powder types are injected into the spray stream through separate powder ports in such a manner that there is substantially no mixing of the powder types in the spray stream. The spray system and substrate being sprayed are moved relative to each other to produce a homogeneous sprayed powder deposit.

Abstract: Metal coated ceramic particles are bonded to a metallic substrate in a high temperature sintering process. A low viscosity binder solution containing fine metallic particulates is first applied to the substrate surface. Then, the coated ceramic particles are disposed upon the substrate surface, and the binder solution and the metal particulates therein are attracted by capillarity into regions of point contact between the ceramic particles and the substrate surface. During a subsequent high temperature sintering operation, the metal coating on the ceramic particles diffuses into the metal substrate, and the metallic particulates melt and solidify to bridge the gap between the substrate and ceramic particles.

Abstract: Annular, circumferentially segmented components of a gas turbine engine are secured to a support structure by C-shaped couplings which prevent movement of the components in a radial and circumferential direction. The coupling has spaced apart legs which trap the component and support structure therebetween, and a key between the legs which engages a keyway formed by cooperating slots in the component and support structure.

Abstract: Techniques are described for the formation of an abrasive surface layer on an article. The surface layer is characterized by a single layer of particles which are evenly spaced apart, in a high density arrangement, within a metallic matrix. In the deposition of the particles on the article, a vacuum is drawn through a perforated plate, wherein the location of each perforation corresponds to the desired location of one particle on the article surface. The vacuum holds one particle over each perforation in the plate, then the plate is positioned over the article and the vacuum level adjusted so that the particles fall onto the article. The matrix is then deposited by plasma arc spraying a superalloy powder. The invention is particularly suited to the formation of an abrasive layer on the tip surface of a blade used in a gas turbine engine.

Abstract: A continuous, high speed process for cutting a length of wire into wire segments and for forming these segments into coils includes the steps of continuously pushing the wire through a cutter at a constant speed, cutting the wire into a succession of wire segments, and directing the segments, in sequence and at the constant speed, to coilers, where they are coiled "on the fly". When a wire segment is completely wound, it is automatically removed from the coiler, whereby the coiler is empty and ready to receive another segment. While one coiler is coiling one of the wire segments, the next segment is directed to a different coiler which is empty. This allows continuous high speed movement of segments through the cutting and coiling process, with no space between the tail end of one segment and lead end of the next segment. Process efficiencies are substantial, and reduce the cost of the coiled wire products.

Abstract: Lubrication of a pinion and bull gear arranged in a bevel gear orientation is accomplished by discharging a stream of lubricant through a nozzle and onto the surface of the pinion web section. Centrifugal forces due to rotation of the pinion cause the lubricant to spread radially outwardly on the web section surface and to form a film thereon. A portion of the lubricant is thrown off of the pinion as the pinion rotates, and strikes the teeth of the bull gear, thereby lubricating the contact surfaces of the bull gear teeth.

Abstract: A process for winding a wire segment to form a wire coil includes the steps of rotating a mandrel by contacting the mandrel outer surface with a moving belt, and directing the wire onto the rotating mandrel between the belt and the mandrel outer surface. The belt holds the wire against the mandrel, and as the mandrel rotates, the wire is wound into a coil on the mandrel outer surface. The belt continues to contact the coil outer surface and to rotate the mandrel until the entire length of the wire segment is wound. As the thickness of the coil increases, the belt partially unwraps from the coil outer surface to adjust belt tension. In one embodiment of the present invention, the belt passes around a pulley attached to a rotatable ring which moves the pulley in a circular path about the axis of the mandrel to cause the belt to unwrap from the coil as the wire builds up on the mandrel.

Abstract: A conduit for carrying a wire being pushed in a downstream direction comprises a duct having an internal flat bottom surface, and fingers spaced along the length of the duct and disposed above the bottom surface, each finger extending downstream and substantially across the width of the duct. The fingers are resiliently movable in a direction which is substantially perpendicular to the bottom surface of the duct when they are struck by the wire, and maintain the wire close to the bottom surface as the wire moves through the duct. The fingers allow the wire to be pushed at a high speed over long distances, and without the wire being twisted, jammed or damaged in the duct.

Abstract: In the compressor section of a gas turbine engine, a stator assembly comprises an outer vane support structure, an inner vane support structure, and a plurality of stator vanes which extend radially therebetween. The inner vane support structure includes a one piece inner ring, and a plurality of shroud sections which surround and are bonded to the ring. Each shroud section has arcuate cavities which receive and retain therein the inner end of a stator vane. The ring and shroud sections are fabricated from composite materials.

Abstract: An apparatus for cutting a length of wire into wire segments includes a pair of adjacent knife carriers, each disposed for rotation about parallel eccentric shafts. The knife carriers each hold a knife blade having a cutting edge. The cutter is constructed and arranged such that the carriers can selectively rotate about either the axis of rotation of the eccentric, wherein the cutting edges do not cut the wire passing between the cutter, or they can rotate about the center of the eccentric, wherein the edges will cut the wire. When the cutting edges cut the wire, their tangential speed is the same as the wire speed.

Abstract: A continuous process for high speed fabrication of wire comprises the steps of directing wire through a first set of drawing dies to reduce the wire diameter to an intermediate diameter, applying a lubricant to the wire during the drawing process, annealing the intermediate diameter wire while it is still coated with some of the lubricant, controlling the tensile forces and elongation of the wire during the anneal, and drawing the annealed intermediate diameter wire to a desired final diameter in a second set of dies. The process is particularly well suited for fabricating fine copper wire having improved mechanical properties.

Abstract: A continuous process for high speed fabrication of wire comprises the steps of directing wire through a first set of drawing dies to reduce the wire diameter to an intermediate diameter, applying a lubricant to the wire during the drawing process, annealing the intermediate diameter wire while it is still coated with some of the lubricant, controlling the tensile forces and elongation of the wire during the anneal, and drawing the annealed intermediate diameter wire to a desired final diameter in a second set of dies. The process is partially well suited for fabricating fine copper wire having improved mechanical properties.