Abstract:
A multilayer coating includes a bond coat layer, a first barrier layer applied on the bond coat layer, and a second barrier layer applied on the first barrier layer. The first barrier layer has a compositional gradient comprising a majority of a first rare earth stabilized zirconia material proximate the bond coat layer to a majority of a second rare earth stabilized zirconia material away from the bond coat layer. The first and second rare earth stabilized zirconia materials are different. The second barrier layer has a compositional gradient comprising a majority of the second rare earth stabilized zirconia material to 100 wt % of a third rare earth stabilized zirconia material away from the first barrier layer.
Abstract:
A vapor deposition system fixture comprises an arm, a rake, a crown gear bearing assembly, a workpiece holder, a thermocouple, and a contact ring assembly. The crown gear bearing assembly is attached to and rotatably engaged with the rake and includes stationary portion and rotating portions. The workpiece holder is configured to rotate with the rotating portion. The thermocouple is configured to rotate with the workpiece holder. The contact ring assembly comprises a housing, a cover, first and second rotating contact rings, and first and second stationary contact rings. The housing is attached to at least one of the arm and the rake. The first and second rotating contact rings are electrically connected to the thermocouple. The first and second stationary contact rings surround the rotating ring. The first and second stationary contact rings are configured to receive an electrical signal from the first and second rotating contact rings.
Abstract:
An environmental sampling system includes a passage in an aircraft component and a removable collector disposed in the passage. The passage has an inlet at a first region and an outlet at a second region. When the aircraft component is in operation the first region is at a greater pressure than the second region such that air flows through the passage from the inlet to the outlet. The removable collector is configured to retain constituents from the air and to react with the media designed to mimic corrosion effects seen at higher temperatures on engine parts. The constituents can then be characterized and correlated to engine deterioration to predict maintenance activity.
Abstract:
An oxidation resistant coating system for a turbine engine component includes a cathodic arc coating applied to a surface of the engine component, a thin APS metallic coating applied to a surface of the cathodic arc coating, and a ceramic top coating applied to a surface of the thin APS metallic coating to improve lifetime of the engine components.
Abstract:
A combustor shell is provided. The combustor shell may include a first aperture at least partially defined by an inner wall of the combustor shell and passing from a diffuser-facing side of the combustor shell to a combustor-facing side of the combustor shell. The combustor shell may include a spacer comprising a first segment coupled to a first flange, wherein the first flange is disposed on the diffuser-facing side of the combustor shell, wherein an outer wall of the spacer is coupled with at least a portion of an inner wall of the combustor shell.
Abstract:
A method for joining engine components includes positioning a first plurality of thermal protection structures across a thermal protection space between a first thermal protection surface and a second thermal protection surface. The first and second engine components are locally joined by forming a first plurality of transient liquid phase (TLP) or partial transient liquid phase (PTLP) bonds along corresponding ones of the first plurality of thermal protection structures between the first thermal protection surface and the second thermal protection surface. The second thermal protection surface is formed from a second surface material different from a first surface material of the first thermal protection surface.
Abstract:
An apparatus for depositing a coating on a part comprises: a chamber; a source of the coating material, positioned to communicate the coating material to the part in the chamber; a plurality of thermal hoods; and means for moving a hood of the plurality of thermal hoods from an operative position and replacing the hood with another hood of the plurality of hoods.
Abstract:
A combustor shell is provided. The combustor shell may include a first aperture at least partially defined by an inner wall of the combustor shell and passing from a diffuser-facing side of the combustor shell to a combustor-facing side of the combustor shell. The combustor shell may include a spacer comprising a first segment coupled to a first flange, wherein the first flange is disposed on the diffuser-facing side of the combustor shell, wherein an outer wall of the spacer is coupled with at least a portion of an inner wall of the combustor shell.
Abstract:
An article has a metallic substrate having a plurality of recesses. A first coating is at least at the recesses and has: a splatted layer; and a columnar layer atop the splatted layer. A second coating is away from the recesses and has: a columnar layer atop the substrate without an intervening splatted layer.
Abstract:
An embodiment of a method includes retaining a first workpiece and a second workpiece selectively on a workpiece fixture disposed within a deposition chamber. The workpiece fixture includes tooling including a first workpiece holder, a second workpiece holder, and a first hollow wall. The first workpiece is separated from the second workpiece using the first hollow wall. Energy is selectively applied and directed within the deposition chamber, from an energy source toward a first crucible, the first crucible including a plurality of walls defining an upper recess contiguous with, and disposed directly above a first lower recess, at least the upper recess open to an interior of the deposition chamber. During the step of selectively applying and directing energy, a gas valve is controlled to maintain a partial vacuum in the deposition chamber of greater than 2 Pa to control a size and overlap of at least one coating zone formed around each of the at least one workpiece.