A method for selectively adhering braze powders to a surface comprises applying a binder material to a surface, depositing a braze powder on the binder material, and then directing a laser beam onto the braze powder while the laser beam moves along a predetermined path relative to the surface. The laser beam selectively heats the braze powder and the binder material along the predetermined path such that the binder material is removed and the braze powder is sintered and bonded to the surface. Thus, a braze deposit is formed at one or more predetermined locations on the surface. After forming the braze deposit, excess braze powder and binder material, that is, the braze powder and binder material not selectively heated by the laser, are removed from the surface.

An assembly for a dual-walled component of a gas turbine engine and methods of forming and repairing a dual-walled component. The assembly includes a cold section part having an outer surface that defines a plurality of impingement apertures, a hot section part including a pre-sintered preform, the hot section part positioned over the outer surface of the cold section part, and a plurality of support structures including the pre-sintered preform, the plurality of support structures positioned between the hot section part and the cold section part, the plurality of support structures separating the hot section part from the cold section part to define at least one cooling channel therebetween.

A method may include removing a portion of a base component adjacent to a damaged portion of the base component to define a repair portion of the base component. The base component may include a cobalt- or nickel-based superalloy, and the repair portion of the base component may include a through-hole extending from a first surface of the base component to a second surface of the base component. The method also may include forming a braze sintered preform to substantially reproduce a shape of the through-hole. The braze sintered preform may include a Ni- or Co-based alloy. The method additionally may include placing the braze sintered preform in the through-hole and heating at least the braze sintered preform to cause the braze sintered preform to join to the repair portion of the base component and change a microstructure of the braze sintered preform to a brazed and diffused microstructure.

A method of preparing a surface for diffusion bonding comprises contacting a binder material with a discontinuous surface comprising surface regions separated by gaps. The binder material is selectively deposited onto the surface regions and has a sufficient viscosity to form a self-supporting layer without flowing into the gaps. The self-supporting layer of binder material comprises a mass density in a range from about 0.001 g/in.sup.2 to about 0.050 g/in.sup.2. A braze powder is distributed over the self-supporting layer of binder material, and a predetermined amount of the braze powder is attached to the binder material. The discontinuous surface is then heated to remove the binder material and adhere the braze powder to the discontinuous surface. Thus, a prewet surface with a braze deposit thereon is formed.

A turbine blade is secured with a turbine disk by a retention assembly. The turbine blade includes a blade stem and the disk includes at least one mount post for mounting of the turbine blade. The retention assembly is secured with the disk by forming a diffusion joint with the disk.

A method of repairing a superalloy component includes subjecting the superalloy component, including a repair area, to a phase agglomeration cycle, which includes stepped heating and controlled cooling of the component. The method further includes applying weld material to the repair area to create a weld surface; and covering the weld surface with brazing material. The component is then subjected to a braze cycle to produce a brazed component. The brazed component is cleaned, and the cleaned component is subjected to a restorative heat treatment to restore the microcrystalline structure and mechanical properties of the component.

One exemplary embodiment of this disclosure relates to a gas turbine engine, including a component having a first portion formed using one of a casting and a forging process, and a second portion formed using an additive manufacturing process.

A blade for a turbomachine, a tip for a blade of a turbomachine and a related method are disclosed. The blade may include a tip body having a shape at least partially configured for coupling to an airfoil body of the blade; at least one coolant passage in the tip body configured for fluid communication with at least one coolant passage in the airfoil body; and a retention member extending from the tip body for coupling to a tip retention member seat in the airfoil body. The tip can be replaced, allowing for changes in the coolant passages in the tip of a blade.

A method of repairing an airfoil is provided. The method includes providing an airfoil with a damaged section and removing the damaged section by machining or cutting an upper section of the airfoil. A replacement section is configured to mate with an upper surface of the airfoil. A presintered preform is provided to join the airfoil and the replacement sections through a resistance brazing process. The presintered preform is configured to mate with the upper surface of the airfoil and a lower surface of the replacement section and inserted between this upper surface and lower surface, creating a stacked airfoil comprising three mated sections in abutting contact. The stacked airfoil is resistance brazed such that only the braze material of the presintered preform melts and the upper surface of the airfoil and the lower surface of the replacement section remain below the grain boundary temperature of the material of the airfoil.

A system may include a current source; a first metal or alloy component with a first major surface electrically coupled to the current source; a second metal or alloy component with a second major surface electrically coupled to the current source; a metal or alloy powder disposed in at least a portion of the joint region; and a controller. The first and second major surfaces may be positioned adjacent to each other to define a joint region. The controller may be configured to cause the current source to output an alternating current that passes from the first component, through at least a portion of the metal or alloy powder, into the second component. The frequency of the alternating current may be configured to cause standing electromagnetic waves within at least a portion of the particles of the metal or alloy powder.