Abstract:
Methods of forming a coating system on a surface of a cobalt-based superalloy component are provided. The method includes forming a nickel-based primer layer on the surface of the cobalt-based superalloy component; forming an intermediate nickel-containing layer on the nickel-based primer layer; and heat treating the cobalt-based superalloy component to form a diffusion coating on the surface of the cobalt-based superalloy component. The intermediate nickel-containing layer includes nickel, chromium, and aluminum. Coated cobalt-based superalloy components formed from such a method are also provided.
Abstract:
A coating process for applying a bifurcated coating to an article is disclosed including applying an aluminizing slurry to a first portion of the article, applying a chromizing slurry to a second portion of the article, and simultaneously heat treating the article, the aluminizing slurry, and the chromizing slurry. Heat treating the aluminizing slurry forms an aluminide coating on the first portion of the article and an aluminide diffusion zone between the article and the aluminide coating. Heat treating the chromizing slurry forms a chromide coating on the second portion of the article and a chromide diffusion zone between the article and the chromide coating. The first portion and the second portion are both maintained in an unmasked state while applying the aluminizing slurry and the chromizing slurry and during the heat treating.
Abstract:
A method for removing oxide materials from a crack of a metallic workpiece comprises: infiltrating an alkali solution into the crack in a pressurized atmosphere or an ultrasonic environment; applying an energy to the crack to react the oxide materials with the alkali solution and form a resultant material; and rinsing the resultant material with an acid solution to remove the resultant material from the crack. The method is easier to penetrate into the inside of the cracks, in particular suitable for cleaning narrow and deep cracks.
Abstract:
Methods for deposition of an aluminide coating on an alloy component positioned within a coating compartment of a retort chamber are provided. According to the method, the coating compartment is purged with an inert gas via a first gas line; a positive pressure is created within the coating compartment utilizing the inert gas; the coating compartment is heated to a deposition temperature; and at least one reactant gas is introduced into the coating compartment while at the positive pressure and the deposition temperature to form an aluminide coating on a surface of the alloy component. Retort coating apparatus are also provided.
Abstract:
Methods for deposition of an aluminide coating on an alloy component positioned within a coating compartment of a retort chamber are provided. According to the method, the coating compartment is purged with an inert gas via a first gas line; a positive pressure is created within the coating compartment utilizing the inert gas; the coating compartment is heated to a deposition temperature; and at least one reactant gas is introduced into the coating compartment while at the positive pressure and the deposition temperature to form an aluminide coating on a surface of the alloy component. Retort coating apparatus are also provided.
Abstract:
Various embodiments of the invention include methods for monitoring a gas turbine component. In some cases, a method includes: analyzing a gas turbomachine component to detect at least one of a void or a porosity of the gas turbomachine component while maintaining a structural integrity of the gas turbomachine component during the analyzing; and providing instructions to perform a hot isostatic pressing (HIP) process on the gas turbomachine component in response to at least one of detecting the void or detecting that the porosity exceeds a threshold.
Abstract:
A method for forming a pattern in an abradable coating includes the step of machining a groove in the abradable coating with a machining tool. The machining tool is configured to machine a top surface, a side surface and a bottom surface of the groove simultaneously. A repeating step repeats the machining step until a desired number of grooves is obtained in the abradable coating.
Abstract:
A method for removing oxide from a metallic substrate is described. The method includes providing a stream of boron trifluoride; heating the metallic substrate at a first temperature; and heating the metallic substrate at a second temperature different from the first temperature. An associated apparatus is also described.
Abstract:
A method includes masking at least one hole of an article with a paste, wherein the hole opens onto a surface of the article, applying a coating to the surface of the article, and removing the paste including contacting the paste with water, leaving at least one open hole in the surface of the coated article. The paste includes about 40-80 wt % of a filler material, about 0.5-20 wt % of an inorganic binder, about 0.5-15 wt % of a polyhydroxy compound and about 5-25 wt % of water. The filler material includes a first material which includes alkali metal doped alumina, zirconium oxide, titanium oxide, silicon dioxide, or a combination thereof and a second material which includes a silicate. A weight ratio between the first and second materials is in a range of about 1-10.
Abstract:
Various embodiments of the disclosure include a thermal coating powder, a system for providing a thermal spray coating, and a method for coating a component. The thermal coating powder may include fused and crushed yttria-stabilized zirconia, wherein the thermal coating powder is in a form of substantially spherically-shaped, solid particles. The system may comprise: a plasma spray gun apparatus having an exit annulus for releasing a plasma jet stream; and a powder injector port coupled to the plasma spray gun apparatus for supplying the thermal coating powder to the plasma jet stream. The method may include: providing a plasma spray gun apparatus including an exit annulus for releasing a plasma jet stream; and spraying the thermal coating powder on the component with the plasma jet stream from the plasma spray gun apparatus.