Abstract: A nickel base powder metallurgy superalloy gas turbine engine disk for a compressor or turbine. The wrought powder metallurgy gas turbine engine disk has desirable fatigue crack growth resistance and a superior balance of tensile, creep rupture and low cycle fatigue strength characteristics. In one embodiment the disk defines a segregation free homogenous structure.

Abstract: A high performance hybrid shaft for use in applications where high stiffness, high temperature capacity and lightweight are important. In one form of the present invention the hybrid shaft is formed of a titanium alloy outer tube having in it's interior a gamma titanium aluminide alloy powder metal that is metallurgically bonded to the outer tube. The gamma titanium aluminide alloy powder metal has a room temperature modulus of elasticity greater than the modulus of elasticity of the titanium alloy tube. The hybrid shaft has a modulus of elasticity greater than modulus of elasticity of the titanium alloy tube, and a density equivalent to that of the titanium alloy tube. The wear resistant capability of the shaft is increased at local regions by surface modification treatment such as plasma ion nitrating or by affixing at the ends of the tube a hardened steel fitting.

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 method for manufacturing a turbine rotor assembly from dissimilar materials to produce a hybrid composite rotor including the steps of: preforming a hub disc of a controlled outer diameter and prefabricating a ring of airfoils including a machine slotted fixture ring of mild steel slotted to receive airfoils inserted therein; and wherein the method further includes the steps of grinding the internal diameter of the mild steel ring to expose the airfoil bases to locate them at a radius line which will correspond to the outer diameter of the hub disc rim to maintain a pressure fit relationship therebetween when the ring of airfoils is pressed or shrunk on the outer diameter of the disc and thereafter sealing exterior joint lines between the mild steel fixture ring, airfoils and hub disc to form a pressure sealed surface on the exterior of the joined parts; subjecting the full outer planar extent of the pressure sealed configuration to an elevated pressure while maintaining it under an elevated temperature to

Abstract: A method of fabricating a hybrid dual property wheel assembly includes the steps of preforming a bladed ring of a highly solidified alloy material including a base with a large diameter central opening therethrough and thereafter supporting a metal disc therein to form front and rear joint lines on either side of the juncture between the bladed ring and the disc. The method further contemplates direction of radio frequency energy to the disc to cause it to thermally expand into radially pressed contact with the inside diameter of the bladed ring at an interface therebetween while maintaining the disc and bladed ring under a continuous vacuum atmosphere and heated by the radio frequency energy for maintenance of a diffusion bond temperature between the expanded disc and the surrounding bladed ring of the wheel assembly to form a metallurgical connection therebetween by metal growth across the interface.

Abstract: A method for manufacturing a turbine rotor assembly from dissimilar materials includes the step of preforming a turbine disc of powdered metal by direct hot isostatic pressing; machining the OD of the disc rim to an exact dimension; prefabricating a ring of airfoil elements having a circular rim with a machined ID therein fit to the OD of the turbine disc; sealing joint lines on side surfaces of the joined parts to create a vacuum at the interface with a high melt temperature sealant; thereafter diffusion bonding the joined and sealed parts by hot isostatically pressing them at temperatures in excess of 1500.degree. F. and under fluid pressure directly applied to the parts in excess of 1000 psi to press the ring ID into intimate contact with the OD of the disc until the dissimilar materials are diffusion bonded to form a high strength butt joint therebetween.