CPC B32B 18/00 (2013.01) [C04B 35/515 (2013.01); C04B 35/52 (2013.01); C04B 35/565 (2013.01); C04B 35/571 (2013.01); C04B 35/573 (2013.01); C04B 35/76 (2013.01); C04B 35/80 (2013.01); C04B 38/068 (2013.01); C04B 41/009 (2013.01); C04B 41/52 (2013.01); C04B 41/89 (2013.01); C04B 2235/3826 (2013.01); C04B 2235/428 (2013.01); C04B 2235/483 (2013.01); C04B 2235/5244 (2013.01); C04B 2235/5248 (2013.01); C04B 2235/5252 (2013.01); C04B 2235/5256 (2013.01); C04B 2235/5436 (2013.01); C04B 2235/616 (2013.01); C04B 2237/30 (2013.01); C04B 2237/365 (2013.01); C04B 2237/368 (2013.01); C04B 2237/38 (2013.01); C04B 2237/385 (2013.01); C04B 2237/403 (2013.01); C04B 2237/61 (2013.01); C04B 2237/704 (2013.01)] | 18 Claims |
1. A method of producing a ceramic matrix composite having a protective ceramic coating, the method comprising:
applying a first surface slurry onto an outer surface of an impregnated fiber preform comprising a framework of ceramic fibers loaded with particulate matter, the first surface slurry comprising particulate ceramic solids dispersed in a solvent;
drying the first surface slurry to form a dried porous layer comprising the particulate ceramic solids;
infiltrating a flowable preceramic polymer comprising silicon into the dried porous layer;
curing the flowable preceramic polymer to form a composite layer on the outer surface, the composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein;
pyrolyzing the cured preceramic polymer to form a porous ceramic layer comprising silicon carbide on the outer surface;
applying a second surface slurry onto the porous ceramic layer to fill cracks formed during pyrolysis, the second surface slurry comprising ceramic particles dispersed in an aqueous or organic solvent;
drying the second surface slurry to form a surface layer on the porous ceramic layer;
infiltrating the impregnated fiber preform, the porous ceramic layer, and the surface layer with a molten material comprising silicon; and
after infiltration with the molten material, cooling the molten material to form a ceramic matrix composite body with a protective ceramic coating thereon and with a densified surface layer on the protective ceramic coating,
wherein the densified surface layer comprises a higher amount of residual silicon than the protective ceramic coating.
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