SUBSURFACE INCLUSIONS OF SPHEROIDS AND METHODOLOGY FOR STRENGTHENING A SURFACE BOND IN A HYBRID CERAMIC MATRIX COMPOSITE STRUCTURE
Structural arrangements and methodology are provided for strengthening a bond between corresponding surfaces of a thermally insulating ceramic coating ( 14 ) and a ceramic matrix composite substrate ( 12 ). A subsurface inclusion of spheroid objects allows to influence a texture of an outer surface of the CMC substrate to enhance the bonding characteristics between the corresponding surfaces.
1 - 11 . (canceled)
12 . A hybrid ceramic matrix composite structure, comprising:
a ceramic matrix composite substrate including a plurality of layers of ceramic fibers;
a first plurality of spaced apart spheroid objects disposed on at least one of the plurality of layers, wherein an outer surface of a subsequent layer disposed over said at least one of the plurality of layers with the spheroid objects influences a texture of the outer surface of the substrate by defining a plurality of corrugations on the outer surface of the substrate; and
a ceramic coating deposited on the outer surface of the substrate, wherein the plurality of corrugations constitutes a bond-enhancing arrangement between the outer surface of the substrate and a corresponding boundary of the coating.
13 . The structure of claim 12 , wherein the outer surface of the subsequent layer is the outer surface of the substrate.
14 . The structure of claim 12 , wherein the spaced apart objects are distributed on said at least one of the layers with a geometric arrangement.
15 . The structure of claim 14 , wherein the geometric arrangement comprises a plurality of parallelograms and the spaced apart objects are positioned at a plurality of corners defined by the plurality of parallelograms.
16 . The structure of claim 15 , wherein the plurality of parallelograms are selected from the group consisting of a rhombus, a square and a rectangle.
17 . The structure of claim 14 , wherein the geometric arrangement comprises a plurality of polygons and the spaced apart objects are positioned at a plurality of corners defined by the polygons.
18 . The structure of claim 12 , wherein the plurality of spheroid objects are arranged on at least two different layers.
19 . The structure of claim 18 , wherein the spaced apart objects are distributed over said at least two different layers with a geometric arrangement.
20 . The structure of claim 12 , wherein the spaced apart objects are distributed over said at least one of the layers with a random arrangement.
21 . The structure of claim 18 , wherein the spaced apart objects are distributed over said at least two different layers with a random arrangement.
22 . The structure of claim 12 , wherein the spheroid objects are selected from the group consisting of a sphere, an ellipsoid, and an object free of corners.
23 . The structure of claim 12 , wherein the plurality of spheroid objects comprise hollow oxide-based spheres.
24 . The structure of claim 12 , wherein the plurality of spheroid objects comprise partially filled oxide-based spheres.
25 . The structure of claim 12 , wherein the plurality of spheroid objects comprise spheres of different dimensions.