Abstract:
A deposition apparatus (20) comprising: a chamber (22); a process gas source (62) coupled to the chamber; a vacuum pump (52) coupled to the chamber; at least two electron guns (26); one or more power supplies (30) coupled to the electron guns; a plurality of crucibles (32,33,34) positioned or positionable in an operative position within a field of view of at least one said electron gun; and a part holder (170) having at least one operative position for holding parts spaced above the crucibles by a standoff height H. The standoff height H is adjustable in a range including at least 22 inches.
Abstract:
A system for measuring a temperature of a rotating workpiece comprises a deposition chamber, a crucible within the deposition chamber, an energy source, a drive system, a temperature sensor, first and second sensor wires, a dynamic electrical connection, and a control system. The crucible is configured to hold a deposition feedstock material. The energy source is configured to evaporate the deposition feedstock material. The drive system is configured to rotate the workpiece such that the evaporated deposition feedstock material can impinge the rotating workpiece. The temperature sensor is configured to sense the temperature of the rotating workpiece. The first and second sensor wires are electrically connected to the temperature sensor. The dynamic electrical connection is configured to electrically communicate the signal indicative of the sensed temperature from the rotatable workpiece holder to the stationary portion. The control system is configured to measure the temperature of the workpiece during rotation.
Abstract:
An electron beam vapor deposition process for depositing coatings includes placing a source coating material in a crucible of a vapor deposition apparatus; energizing the source coating with an electron beam raster pattern that delivers a controlled power density to the material in the crucible forming a vapor cloud from the source coating material; and depositing the source coating material onto a surface of a work piece.
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:
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.
Abstract:
An article includes a substrate and a multi-layered ceramic barrier coating on a substrate. The coating includes, from the substrate outward, a first layer of a low-dopant ceramic material and a second layer high-dopant ceramic material. The first layer has a columnar microstructure and the second layer has a branched columnar microstructure.
Abstract:
A deposition apparatus (20) comprising: a chamber (22); a process gas source (62) coupled to the chamber; a vacuum pump (52) coupled to the chamber; at least two electron guns (26); one or more power supplies (30) coupled to the electron guns; a plurality of crucibles (32,33,34) positioned or positionable in an operative position within a field of view of at least one said electron gun; and a part holder (170) having at least one operative position for holding parts spaced above the crucibles by a standoff height H. The standoff height H is adjustable in a range including at least 22 inches.
Abstract:
A deposition apparatus comprises: an infeed chamber; a preheat chamber; a deposition chamber; and optionally at least one of a cooldown chamber and an outlet chamber. At least a first of the preheat chamber and the cooldown chamber contains a buffer system for buffering workpieces respectively passing to or from the deposition chamber.
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.