Densified polymer infiltrated and pyrolysis-based CMC articles

A method of densifying a ceramic matrix composite (CMC) article comprising the steps of:

• pyrolyzing a CMC article having a silicon carbide matrix using a polymer infiltrated and pyrolysis (PIP) process until a desired initial porosity of silicon carbide pores within the silicon carbide matrix is achieved, wherein the CMC article is pyrolyzed at a temperature of 1000-1800° C. to achieve the initial porosity within the silicon carbide matrix;
• coating silicon carbide pores within the silicon carbide matrix with carbon;
• pyrolyzing the carbon using a PIP process to form carbon pores on the silicon carbide matrix, wherein the carbon is pyrolyzed at a temperature of 1000-1800° C.;
• coating the carbon pores with silicon;
• and
• heat treating the CMC article to draw the silicon into the carbon pores to react with the carbon and create additional silicon carbide that is integrated with the silicon carbide of the CMC article to densify the CMC article.