摘要:
A titanium-alloy article is produced by providing a workpiece of an alpha-beta titanium alloy having a beta-transus temperature, and thereafter mechanically working the workpiece at a mechanical-working temperature above the beta-transus temperature. The mechanically worked workpiece is solution heat treated at a solution-heat-treatment temperature of from about 175° F. below the beta-transus temperature to about 25° F. below the beta-transus temperature, quenched, overage heat treated at an overage-heat-treatment temperature of from about 400° F. below the beta-transus temperature to about 275° F. below the beta-transus temperature, and cooled from the overage-heat-treatment temperature.
摘要:
The present invention is a process for applying oxide paint as a touch-up paint for an oxide-based corrosion inhibiting coating with at least one imperfection region. Such oxide-based corrosion inhibiting coatings are applied on superalloy components used for moderately high temperature applications, such as the superalloy components found in the high-pressure turbine (HPT) section of a gas turbine engine, including turbine disks and seals. However, during the application of oxide-based corrosion inhibiting coatings, imperfection regions sometimes occur, exposing the superalloy substrate beneath the oxide-based corrosion inhibiting coating. Such imperfection regions can include a spalled region, a scratched region, a chipped region, an uncoated region, or combinations thereof. The process of the present invention is useful where aircraft engine components have been treated with a corrosion inhibiting three-layer paint oxide system comprising chromia and alumina, but where a small imperfection region or regions within the layer oxide system are present after initial manufacture, refurbishment, or repair of the component.
摘要:
A turbine engine rotor component, such as a compressor or turbine disk or seal element, is protected from corrosion by implanting aluminum or chromium ions, or mixtures thereof, on the surface of the component. Additional metal ions, such as rare earth and reactive elements, may also be implanted on the surface of the component. The component may be heated in a nonoxidizing atmosphere at a specified temperature and time to diffuse the ions into the surface. The component is typically then heated or maintained at an elevated temperature in the presence of oxygen to form an oxide coating on the surface of the component.
摘要:
The disclosure relates generally to mold compositions and methods of molding and the articles so molded. More specifically, the disclosure relates to mold compositions, intrinsic facecoat compositions, and methods for casting titanium-containing articles, and the titanium-containing articles so molded.
摘要:
A composition comprising a particulate corrosion resistant component, and a glass-forming binder component. The particulate corrosion resistant component comprises from 0 to about 95% alumina particulates, and from about 5 to 100% corrosion resistant non-alumina particulates having a CTE greater than that of the alumina particulates. Also disclosed is an article comprising a turbine component comprising a metal substrate and a corrosion resistant coating having thickness up to about 10 mils (254 microns) overlaying the metal substrate. At least the layer of this coating adjacent to the metal substrate comprises a glass-forming binder component and the particulate corrosion resistant component adhered to the glass-forming binder component. Further disclosed is a method comprising the following steps: (a) providing a turbine component comprising the metal substrate; (b) depositing on the metal substrate a corrosion resistant coating composition; and (c) curing the deposited corrosion resistant coating composition to form at least one layer of a corrosion resistant coating having a thickness up to about 10 mils (254 microns).
摘要:
A turbine engine rotor component, such as a compressor or turbine disk or seal element, is protected from corrosion by depositing an aluminum or chromium coating on the component. The deposition can be performed by a vapor deposition process, such as metal organic chemical vapor deposition (MOCVD), to a coating thickness of from about 0.2 to about 50 microns, typically from about 0.5 to about 3 microns. In one embodiment, the method is conducted in a vapor coating container having a hollow interior coating chamber, and includes the steps of loading the coating chamber with the component to be coated; and flowing a tri-alkyl aluminum or chromium carbonyl coating gas into the loaded coating chamber at a specified temperature, pressure, and time to deposit an aluminum or chromium coating on the surface of the component. The coated component is then heated in a nonoxidizing atmosphere to a specified temperature to form an aluminide or chromide coating on the surface. The coated component is typically then heated or maintained at an elevated temperature in the presence of oxygen to form an oxide coating on the surface of the component.
摘要:
The present disclosure relates to a titanium-containing article casting mold composition comprising calcium aluminate and an X-ray or Neutron-ray detectable element. Furthermore, present embodiments teach a method for detecting sub-surface ceramic inclusions in a titanium or titanium alloy casting by combining calcium aluminate, an element more radiographically dense than the calcium aluminate, and a liquid to form a slurry; forming a mold having the calcium aluminate and the radiographically dense element from the slurry; introducing a titanium aluminide-containing metal to the radiographically dense element-bearing mold; solidifying said titanium aluminide-containing metal to form an article in the mold; removing the solidified titanium aluminide-containing metal article from said mold; subjecting the solidified titanium aluminide-containing article to radiographic inspection to provide a radiograph; and examining said radiograph for the presence of the radiographically dense element on or in the article.
摘要:
A method for producing an article such as a turbine component that is coated with a β-phase, high aluminum content coating, such as substantially stoichiometric NiAl, and which has a surface finish suitable for application of a ceramic topcoat. The method involves heating the coated article to near the brittle-ductile transition temperature of the coating and impacting the coating with particles of a preselected size so that the brittle coating is not adversely affected by chipping or breakage. The impacting produces a surface finish of 120 micro-inches or finer so that a ceramic thermal barrier layer can be applied over the coating. The preferred method of improving the surface finish utilizes heated peening media to impact the heated coated article, thus allowing use of a broader selection of peening media.
摘要:
A method for forming an aluminide coating on a turbine engine component having an external surface and an internal cavity defined by an internal surface that is connected to the external surface by at least one hole. The method is conducted in a vapor coating container having a hollow interior coating chamber, and includes the steps of loading the coating chamber with the component to be coated; flowing a tri-alkyl aluminum coating gas into the loaded coating chamber at a specified temperature, pressure, and time to deposit an aluminum coating on the external and internal surfaces of the component; and heating the component in a nonoxidizing atmosphere at a specified temperature and time to form an aluminide coating on the external and internal surfaces. The coated component is typically then maintained at an elevated temperature in the presence of oxygen to form an oxide coating on the external and internal surfaces of the component. In one embodiment, the turbine engine component is a turbine engine blade having an external surface and an internal cooling cavity having an internal surface that is connected to the external surface by cooling holes.