Modified ceramic structures and methods of making the same

Claim 1

A self-supporting ceramic composite body comprising: 1) an initial ceramic composite body which comprises a polycrystalline oxidation reaction product embedding a substantially inert filler material, said oxidation reaction product selected from the group consisting of alumina, aluminum nitride, aluminum boride, aluminum carbide, silica, silicon nitride, silicon boride, silicon carbide, titania, titanium nitride, titanium boride, titanium carbide, tin oxide, tin nitride, tin boride, tin carbide, zirconia, zirconium nitride, zirconium carbide, hafnia, hafnium nitride, hafnium carbide, and hafnium boride being formed by a directed oxidation reaction of a molten parent metal selected from the group consisting of aluminum, silicon, titanium, tin, zirconium and hafnium, with an oxidant selected from the group consisting of an oxygen containing gas, a nitrogen containing gas, a boron containing element or compound, and a carbon containing element or compound, such that said filler material is embedded by said oxidation reaction product, said initial ceramic composite body having at least some interconnected porosity which is at least partially accessible from at least one surface of said initial ceramic composite body; and a second ceramic component selected from the group consisting of chromia and silica being disposed in at least a portion of said porosity.