PROCESSO PARA FAZER UM PRODUTO OU CORPO CERAMICO COMPOSTO POROSO COM SUPERFICIE DENSA E PRODUTO ASSIM OBTIDO

摘要

There is disclosed a method for making a self-supporting ceramic composite article having a porous core bearing a dense surface layer formed integrally with said core. A preform comprises a filler material and parent metal distributed therethrough, wherein the volume percent of parent metal is sufficient to form a volume of oxidation reaction product exceeding the total volume available within said preform. The parent metal is molted and reacted with an oxidant to form an oxidation reaction product filling the spatial volume and leaving voids. The reaction is continued to further transport molten parent metal through the oxidation reaction product to at least one surface of the preform to form oxidation reaction product on said surface substantially free of voids thereby forming a relatively dense surface layer.