Patterned abradable coating and methods for the manufacture thereof

Patent metadata

Field	Value
Publication number	US-2016236995-A1
Application number	US-201615046240-A
Country	US
Kind code	A1
Filing date	Feb 17, 2016
Priority date	Feb 17, 2015
Publication date	Aug 18, 2016
Grant date	—

Abstract

A ceramic article includes a flexible backing selected from paper, woven fabric, non-woven fabric, polymeric films, metal foils, and combinations thereof. A green ceramic layer is on a first side of the flexible backing, wherein the green ceramic layer includes a ceramic material and a polymeric binder. A major surface of the green ceramic layer includes a pattern of features.

First claim

1 . A ceramic article, comprising:
a flexible backing selected from paper, woven fabric, non-woven fabric, polymeric films, metal foils, and combinations thereof; and a green ceramic layer on a first side of the flexible backing, wherein the green ceramic layer comprises a ceramic material and a polymeric binder, and wherein a major surface of the green ceramic layer comprises a pattern of features.

2 . The ceramic article of claim 1 , wherein the backing comprises a polymeric film.

3 . The ceramic article of claim 1 , wherein the ceramic material comprises silicates selected from the group consisting of rare earth (RE) disilicates, RE monosilicates, barium strontium aluminum silicate, and mixtures and combinations thereof.

4 . The ceramic article of claim 1 , wherein the binder in the green ceramic layer comprises polyvinyl buteral.

5 . The ceramic article of claim 1 , wherein the green ceramic layer further comprises a solvent selected from the group consisting of alcohols, acetone, and methyl ethyl ketone (MEK), and mixtures and combinations thereof.

6 . The ceramic article of claim 1 , further comprising a support layer on a second side of the backing opposite the first side.

7 . The ceramic article of claim 1 , further comprising a release liner on the major surface of the green ceramic layer and overlying the pattern.

8 . The ceramic article of claim 1 , wherein the pattern comprises an array of grooves, an array of blocks, an array of apertures, a honeycomb pattern, and combinations thereof.

9 . The ceramic article of claim 8 , wherein the features comprise hemispherically-shaped depressions.

10 . The ceramic article of claim 9 , wherein each row of depressions in the array is offset with respect to an adjacent row of depressions, and wherein each column of depressions is offset with respect to an adjacent column of depressions.

11 . The ceramic article of claim 9 , wherein the depressions in a first row are a distance r apart, and the depressions in a second row adjacent to the first row are positioned a distance r/2 between the depressions in the first row.

12 . The ceramic article of claim 9 , wherein the ratio of the diameter of the depressions (x) to the distance between the depressions (r) is about 0.25 to about 0.75.

13 . The ceramic article of claim 9 , wherein the depressions are selected and arranged on the surface to provide the layer with a porosity of about 25% to about 75%.

14 . The ceramic article of claim 9 , wherein the coating has a porosity of about 25% to about 50%.

15 . A method, comprising:
forming a slurry comprising a ceramic material, a polymeric binder, and at least one solvent; coating the slurry on a flexible backing to form a green ceramic layer with a disperse phase of the ceramic material in a matrix of the polymeric binder; and machining an array of features into a surface of the green ceramic layer to form a machined green ceramic article.

16 . The method of claim 15 , further comprising drying the slurry after coating the slurry on the flexible backing.

17 . The method of claim 15 , wherein the flexible backing comprises a polymeric film.

18 . The method of claim 15 , wherein the ceramic material comprises a silicate.

19 . The method of claim 18 , wherein the silicate is selected from the group consisting of rare earth (RE) disilicates, RE monosilicates, barium strontium aluminum silicate, and mixtures and combinations thereof.

20 . The method of claim 15 , wherein the polymeric binder comprises polyvinyl buteral.

Assignees

• Rolls Royce Corp

Inventors

• Lai Benjamin John Bowin
• Lee Kang N
• Thomas David J

Classifications

• C04B35/16

  based on silicates other than clay {(zircon C04B35/48)} · CPC title

• C04B41/91 Primary

  involving the removal of part of the materials of the treated articles, e.g. etching · CPC title

• C04B35/195

  Alkaline earth aluminosilicates, e.g. cordierite {or anorthite} · CPC title

• C04B41/009

  characterised by the material treated · CPC title

• C04B2237/341

  Silica or silicates · CPC title