Abstract:
A method includes forming a multi-layered ceramic barrier coating under a chamber pressure of greater than 1 Pascals. In the method, low- and high-dopant ceramic materials are evaporated using input evaporating energies that fall, respectively, above and below a threshold for depositing the materials in a columnar microstructure (low-dopant) and in a branched columnar microstructure (high-dopant).
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 embodiment of an apparatus includes a deposition chamber, a workpiece fixture including a first workpiece holder, and a first crucible. The workpiece holder is configured to retain a first workpiece in the deposition chamber. The first crucible includes a body including at least one wall defining a non-circular upper recess with a base. A first lower recess is formed below the base of the upper recess and configured to retain a first primary coating feedstock therein.
Abstract:
A method includes generating a plasma plume with a plasma gun, delivering a plurality of coating materials to the plasma plume with a powder feeder assembly to vaporize the coating materials. The delivery includes delivering a first (bond coat) material from a first powder feeder to the plasma gun, ceasing delivery of the first material, increasing a rate of delivery of a second (rare earth stabilized zirconia) material from a second powder feeder to the plasma plume, increasing a rate of delivery of a third material (a rare earth stabilized zirconia material different from the second material) from a third powder feeder to the plasma plume, decreasing a rate of delivery of the second material, and decreasing a rate of delivery of the third material, and depositing the plurality of coating materials on a work piece to produce a layered coating with blended transitions between coating layers.
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:
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:
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:
A method for casting comprising: providing a seed, the seed characterized by: an arcuate form and a crystalline orientation progressively varying along an arc of the form; providing molten material; and cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material.
Abstract:
A method for casting comprising: providing a seed, the seed characterized by: an arcuate form and a crystalline orientation progressively varying along an arc of the form; providing molten material; and cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material.
Abstract:
Disclosed herein is a method comprising mixing a carrier liquid with particles and/or with a particle precursor to form a suspension or solution respectively; where the particles comprise a metal oxide; and where the particle precursor comprises a metal salt; injecting the suspension or solution through a plasma flame; and depositing the particles and/or the particle precursor onto a substrate to form an first abradable coating; where the first abradable coating comprises a plurality of cracks or voids that are substantially perpendicular to the substrate surface, where the substrate is a hub surface of a gas turbine engine or where the substrate is a cantilever stator.