Improvement of the thermal stability of continuous SiC fiber reinforced SiC
ceramic matrix composites (SiCf/SiC CMC) by the pre-treatment of SiC fillers
and the suppression of oxidation during polymer impregnation and pyrolysis
(PIP) process were investigated. Dense SiCf/SiC CMCs were fabricated using
the slurry infiltration and PIP process under a purified argon atmosphere.
Structure and mechanical properties of the SiCf/SiC CMC heated at different
temperatures were evaluated. The flexural strength of the SiCf/SiC CMC
decreased only 15.3%after heating at 1400 ?C, which exhibited a clear
improvement compared with the literature data (49.5% loss), where severe
thermal deterioration of SiCf/SiC composite occurred at high temperatures by
the crystallization and decomposition of the precursor-derived ceramic
matrix. The thermal stability of the SiCf/SiC CMC fabricated by PIP process
was improved by the pre-treatment of SiC fillers for removing oxides and the
strict atmosphere control to prevent oxidation.