Abstract: High efficiency, thin-walled turbine components such as turbine blade airfoils comprise a superalloy substrate covered by a thin skin. The thin skin may be bonded to the inner spar structure of a turbine blade airfoil by a transient liquid phase bonding process. The inner spar preferably comprises a cast single crystal nickel base superalloy. The thin skin may comprise a single crystal or polycrystalline nickel base superalloy or the like.

Abstract: Large gas turbine blades made from separate cast segments of superalloys are disclosed. The turbine blade is designed such that bond lines between adjacent segments are placed in low stress regions of the blade. The cast superalloy segments of the blades are aligned and fitted together with specified tolerances. The turbine blade segments are then joined by transient liquid phase bonding, followed by a controlled heat treatment which produces the desired microstructure in the bond region. The method allows for the production of large, high quality turbine blades by joining small, high quality cast superalloy sections, in comparison with prior attempts to cast large turbine blades as single pieces which have produced very low yields and high individual component costs.

Abstract: A method of bonding cast superalloys is disclosed. The method includes the steps of casting separate superalloy component parts, machining the mating surfaces of the separate parts in a controlled manner to avoid recrystallization of the material and to ensure a tight fit between the parts, bonding the parts together, and thermally treating the bonded component. In a preferred embodiment, the component is a turbine blade for a land-based gas turbine.

Abstract: A turbine blade with a cooling air flow path specifically directed toward cooling the platform portion of the blade root. Cooling air passages are formed in the blade root platform just below its radially outward facing surface on an overhanging portion of the platform opposite the convex surface of the blade airfoil. Each of these passage extends radially outward from an inlet that receives a flow of cooling air, and then extends through the platform. Cavities are formed in a radially inward facing surface of an over hanging portion of the platform opposite the concave surface of the blade airfoil. An impingement plate directs cooling air as jets into these cavities. A passage is connected to the cavities and directs this cooling air through the overhanging portion of the platform opposite the concave surface.

Abstract: Processes for constructing complex turbine structures by the assembly of less complex sub-structures. The component sub-structures are bonded together at opposed mating surfaces by transient liquid bond phase techniques. The sub-structure mating surfaces are machined prior to application of the bonding material to remove oxide from the mating surfaces and ensure dimensional tolerances. Bonding material is applied to the mating surfaces by sputter deposition. Masks can be applied to the mating surfaces prior to application of the bond material so as to selectively apply bond material at only predetermined locations on the mating surface, thus eliminating excessive use of bond material for bonding the component sub-structures.