A steam turbine rotor blade for forming a turbine rotor cascade of a steam turbine includes a rotor blade main body having a blade portion, a blade base portion and a first coupling portion, which has first facing surfaces, provided on opposite end sides of the blade portion, and a second coupling portion provided in an intermediate portion of the blade portion and having second facing surfaces. The steam turbine rotor blade also includes a coating layer which is made of a Co-based alloy having a single composition on a surface of at least one of the first and facing surfaces with a diffusion layer having a thickness of 10 μm or less provided between the coating layer and the surface.

Methods for processing bonded dual alloy rotors are provided. In one embodiment, the method includes obtaining a bonded dual alloy rotor including rotor blades bonded to a hub disk. The rotor blades and hub disk are composed of different alloys. A minimum processing temperature (T.sub.DISK.sub._.sub.PROCESS.sub._.sub.MIN) for the hub disk and a maximum critical temperature for the rotor blades (T.sub.BLADE.sub._.sub.MAX) is established such that T.sub.BLADE.sub._.sub.MAX is less than T.sub.DISK.sub._.sub.PROCESS.sub._.sub.MIN. A differential heat treatment process is then performed during which the hub disk is heated to processing temperatures equal to or greater than T.sub.DISK.sub._.sub.PROCESS.sub._.sub.MIN, while at least a volumetric majority of each of the rotor blades is maintained at temperatures below T.sub.BLADE.sub._.sub.MAX. Such a targeted differential heat treatment process enables desired metallurgical properties (e.g., precipitate hardening) to be created within the hub disk, while preserving the high temperature properties of the rotor blades and any blade coating present thereon.

A seal assembly includes a seal arc segment that defines radially inner and outer sides and first and second axial arc segment sides, a carriage that carries the seal arc segment, and a cover that defines first and second axial cover sides. The second axial cover side is adjacent the first axial arc segment side.

A turbine blade that includes an airfoil defined by a concave shaped pressure side outer wall and a convex shaped suction side outer wall that connect along leading and trailing edges and, therebetween, form a radially extending chamber for receiving the flow of a coolant. The turbine blade may further include a rib configuration that partitions the chamber into radially extending flow passages, and a blade outer shell that defines an outer surface of the airfoil. The rib configuration is a non-integral component to the blade outer shell.

A method treats a brush seal at a tip end of the brush seal. The method includes contacting the tip end of the brush seal to an oxidation-resistant, wear-resistant coating composition and heat-treating a distal portion of the bristles to form an oxidation-resistant, wear-resistant coating on the distal portion from the oxidation-resistant, wear-resistant coating composition. A brush seal includes a brush support and bristles extending from the brush support with a distal portion coated by an aluminide diffusion coating. A brush seal assembly includes a non-rotary component and a rotary component. The non-rotary component includes a brush seal including a bristle pack. The bristle pack includes bristles extending from a brush support with a distal portion coated by an aluminide diffusion coating. The rotary component has a sealing surface contacting the distal portion of the brush seal to form a turbine seal between the rotary component and the non-rotary component.

Embodiments of the disclosure provide a turbomachine component, including: a base portion configured for mounting on a rotor; an airfoil portion having a first end coupled to the base portion, and a second end opposite the first end. A creep resistance of the airfoil portion is greater than the base portion, and a fracture toughness of the airfoil portion is less than the base portion. A tip portion may be coupled to the second end of the airfoil portion. A creep resistance of the tip portion is less than the airfoil portion and greater than the base portion. A fracture toughness of the tip portion is less than the base portion and greater than the airfoil portion.

A steam turbine and a method for internally cooling the same. The steam turbine includes an outer casing and an inner casing; a rotor having a balancing piston, the rotor being rotatably mounted inside the inner casing; and a steam flow channel formed between the inner casing and the rotor. Moving blades fitted with the rotor and stationary blades fitted with the inner casing are alternately arranged to form multiple stages of blade groups, and an interlayer for steam to circulate is formed between the inner casing and the outer casing. The multiple stages of blade groups include a first set blade staging and a second set blade staging; and the top of the balancing piston is provided with a first chamber and a second chamber. A first channel disposed in the inner casing connects the flow passage downstream of the first set blade staging to the first chamber; and a second channel connects the second chamber to the interlayer and connects the interlayer to the flow passage downstream of the second set blade staging.

There is provided a cobalt-based alloy product comprising: in mass %, 0.08-0.25% C; more than 0.04% and 0.2% or less N, the total amount of C and N being more than 0.12% and 0.28% or less; 0.1% or less B; 10-30% Cr; 5% or less Fe and 30% or less Ni, the total amount of Fe and Ni being 30% or less; W and/or Mo, the total amount of W and Mo being 5-12%; 0.5% or less Si; 0.5% or less Mn; 0.5 to 2 mass % of an M component being a transition metal other than W and Mo and having an atomic radius of more than 130 pm; and the balance being Co and impurities. The product comprises matrix phase crystal grains, in which particles of MC carbides, M(C,N) carbonitrides and/or MN nitrides including the M component are precipitated at an average interparticle distance of 0.13-2 μm.

A gas turbine engine includes a turbine section having a turbine rotor and at least one blade extending outwardly of the turbine rotor. The turbine rotor rotates about an axis of rotation. A blade outer air seal is positioned radially outward of the at least one blade. The blade outer air seal has an axially forward hook and an axially aft hook supported to static structure. An axial seal is attached to static structure forward of the forward hook, and has a sealing portion extending in an aft direction. A sealing surface member is positioned intermediate an aft end of the axial seal and a forward end of the forward hook to provide a sealing surface for sealing between the seal and the blade outer air seal.

The invention relates to a method for coating a component, which is provided for the hot gas duct of a turbomachine, wherein the coating material is applied onto the uncoated component surface in the form of particles in mixture with a binding agent, and the component with the particle-treated binding agent thereupon then undergoes thermal treatment in such a way that the binding agent is released and the coating material remains on the component.