3-D CERAMIC-MATRIX COMPOSITE DEVELOPMENT

3-D silicon carbide ceramic matrix composites were developed using the polymer precursor infiltration process. Process optimization for the fiber preform used in this study produced composites that had mechanic al properties equivalent or superior to comparable carbon/carbon compo sites. The optimized processing conditions were such that, even though superior mechanical properties were achieved the aeroconvective perfo rmance was inferior to continuous fiber silicon carbide ceramic matrix composites fabricated via the Chemical Vapor Infiltration/Deposition (CVI/ CVD) process. The process limitations were established by the sp ecific fibers used in the preforms. These fibers, Nextel(R) and Nicalo n(R) show degradation above 1,200 degrees C and therefore limited the temperature set in the study.