Abstract: A curable masking material for protecting a passage hole in a metal-based substrate is formed of an extrudable resin composition. The resin composition is thermally stable at elevated temperatures, and does not serve as an adhesion site for any coatings which are applied over the masking material. In addition, the resin composition has non-Newtonian flow characteristics and is adapted to form a protrusion extending from the passage hole upon extrusion to fill the passage hole.

Abstract: A method for temporarily protecting at least one passage hole in a metal-based substrate from being obstructed by at least one coating applied over the substrate is disclosed.

Abstract: A method for improving the quality of a zirconia-based coating deposited on a metal-based substrate is disclosed. The method comprises the step of plasma-spraying zirconia powder of substantially uniform particle size onto the substrate. The disclosure further relates to an improved powder source material for use in a plasma. The source material is zirconia powder having a uniform particle size, and optionally, a uniform particle density. The use of such a material results in improved thermal barrier coatings for various substrates, such as those found in a turbine engine.

Abstract: An improved thermal barrier coating for metal substrates such as superalloys is disclosed. The coating is a slurry composition, comprising spheres of zirconia, at least some of which are hollow, contained within a porous oxide matrix, such as aluminosilicate. The slurry composition can be applied by slurry casting or similar techniques to the desired surface. Coating methods are also described. In general, they involve the application of successive layers of variations of the slurry composition, with various curing techniques used between layers and after the final coating is applied. Another embodiment of this invention embraces a composite coating, comprising (i) an oxide matrix phase; (ii) zirconia spheres embedded in the oxide matrix; and (iii) a porous phase.

Abstract: A method for temporarily protecting at least one passage hole in a metal-based substrate from being obstructed by at least one coating applied over the substrate is disclosed. The method includes the following steps:(a) filling and covering the hole with a curable masking material which forms a protrusion over the hole;(b) curing the masking material;(c) applying at least one coating over the substrate and the masking material, wherein the coating does not substantially adhere to the protrusion; and then(d) removing the masking material to uncover the passage hole.Usually, there are an array of holes, and they serve as conduits for cooling gasses for an engine component. The curable masking material exhibits substantially non-Newtonian flow characteristics which make it especially suitable for forming protrusions of the proper size and shape on the coating-side of an engine part.

Abstract: An improved thermal barrier coating for metal substrates such as superalloys is provided. The coating is a slurry composition, comprising spheres of zirconia, at least some of which are hollow, contained within a porous oxide matrix, such as aluminosilicate. The slurry composition can be applied by slurry casting or similar techniques to the desired surface. Coating methods involve the application of successive layers of variations of the slurry composition, with various curing techniques used between layers and after the final coating is applied. Another embodiment of this invention embraces a composite coating, comprising (i) an oxide matrix phase; (ii) zirconia spheres embedded in the oxide matrix; and (iii) a porous phase.