Fabrication of Silicon Carbide‐Mullite Composite by Melt Infiltration

The melt infiltration method was used to fabricate a SiC‐mullite composite at high temperature. Mullite was successfully obtained from a SiO 2 and Al 2 O 3 powder mixture by melting above 1830°C in a BN crucible with a lid. When infiltrated into a porous SiC preform, the mullite significantly reacted with SiC to form gaseous SiO and CO, even at the lowest investigated temperature of 1830°C, consuming SiO 2 and leaving Al 2 O 3 and silicon phases in the sample. The relevant reactions were studied in detail. A closed system was adopted to suppress the reaction, and a dense composite was successfully obtained.