Mitigating pyrophoric deposits in exhaust piping during SIC CVI/CVD processes by introducing water vapor into an outlet portion of a reaction chamber

A system for manufacturing a ceramic matrix composite component, comprising:

• a reaction chamber including an inlet portion configured to receive a porous preform and a gaseous precursor, and further including an outlet portion configured to define a gas mixing space;
• an exhaust conduit in fluid communication with the outlet portion of the reaction chamber;
• and
• a supply conduit configured to deliver a mitigation agent to the exhaust conduit downstream of the outlet portion;
• wherein the outlet portion comprises a porous gas mixing substrate disposed downstream from the inlet portion, wherein the porous gas mixing substrate comprises one of a volcanic rock and a graphite;
• the porous preform comprises silicon carbide (SiC);
• the gaseous precursor comprises at least one of a chlorosilane, a chlorinated carbosilane, and a methyltrichlorosilane;
• the mitigating agent comprises at least one of water vapor and ammonia;
• and
• a chlorine in at least one of (i) the gaseous precursor and (ii) an intermediate species of the gaseous precursor is replaced with a hydroxyl group in response to being reacted with the mitigating agent.