Abstract:
THERMAL BARRIER COATINGS WITH LOW THERMAL CONDUCTIVITY A thermal barrier coating comprising from 0.5 to 22.5 mol% of at least one first oxide having a formula A203 where A is selected from the group consisting of La, Sm, Tb, Tm, and Lu combined with a second oxide selected from the group consisting of zirconia, hafnia, and ceria.
Abstract:
THERMAL BARRIER COATING FOR COMBUSTOR PANELS A method is disclosed that selectively applies thermal barrier coatings that exhibit different degrees of thermal conductivity to different inner surface areas of engine combustor panels. Different types of TBCs are applied to predetermined inner surface areas of a combustor panel based on empirical observation or prediction. TBCs exhibiting low thermal conductivity are applied to combustor panel areas that are exposed to hotter temperatures and TBCs exhibiting higher thermal conductivity are applied to areas that are exposed to lower temperatures.
Abstract:
A workpiece, such as a turbine engine component, comprises a substrate, a thermal barrier coating on the substrate, and a hard erosion barrier deposited over the thermal barrier coating. The erosion barrier preferably has a Vickers hardness in the range of from 1300 to 2750 kg/mm2. The erosion barrier may be formed from aluminum oxide, silicon carbide, silicon nitride, or molybdenum disilicide. The erosion barrier may be formed using either an electrophoretic deposition process or a slurry process.
Abstract:
A process of coating an article includes the steps of (1) forming a layer of a ceramic based compound on an article; (2) providing a solution containing a metal as a particulate having a diameter of about 10 nanometers to about 1000 nanometers and present in an amount of about 25 percent to about 50 percent by volume of the solution; (3) contacting the ceramic based compound layer with the solution; (4) drying the article; and (5) optionally repeating steps (3) and (4).
Abstract:
A turbine component has a substrate formed from a ceramic material selected from the group consisting of a monolithic ceramic material and a composite ceramic material and a thermal barrier coating bonded to the substrate. In one embodiment, the ceramic material forming the substrate is selected from the group of silicon nitride and self-reinforced silicon nitride. In another embodiment, the ceramic material forming the substrate is selected from the group consisting of a silicon carbide-silicon carbide material and a carbon-carbon material. At least one bond coat layer may be interposed between the substrate and the thermal barrier coating.
Abstract:
A ceramic material having particular utility as a thermal insulating or thermal barrier coating on metallic substrates is provided. The ceramic material broadly comprises at least one oxide and the balance comprising a first oxide selected from the group consisting of zirconia, ceria, and hafnia. The at least one has a formula A2O3 where A is selected from the group consisting of La, Pr, Nd, Sm, Eu, Tb, In, Sc, Y, Dy, Ho, Er, Tm, Yb, Lu, and mixtures thereof. The present invention also broadly relates to an article having a metal substrate and a thermal barrier coating as discussed above.
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 method for use in a physical vapor deposition coating process includes depositing a ceramic coating material from a plume onto at least one substrate to form a ceramic coating thereon, and during the deposition, rotating the at least one substrate at rotational speed selected with respect to deposition rate of the ceramic coating material onto the at least one substrate.
Abstract:
A thermal barrier coating is applied to a turbine engine component having a substrate. The thermal barrier coating has a first layer which has a strain tolerant columnar microstructure at an interface with the substrate for spallation resistance and a second layer which is porous conduction and radiation thermally resistant at an outer surface of the thermal barrier coating.
Abstract:
The thermal barrier coating system comprises a matrix of a first chemistry with multiple embedded second phases of a second chemistry. The matrix comprises a stabilized zirconia. The second regions comprise at least 40 mole percent of oxides having the formula Ln2O3, where Ln is selected from the lanthanides La through Lu, Y, Sc, In, Ca, and Mg with the balance zirconia (ZrO2), hafnia (HfO2), titania (TiO2), or mixtures thereof. The second phases have a characteristic thickness (T6) of less than 2.0 micrometers (μm). The spacing between second phases has a characteristic thickness (T5) of less than 8.0 micrometers (μm).