Processing of Carbon Fiber Three-Dimensional Braided Perform Reinforced Silicon Carbide Composite with Different Interphases

摘要

The processing of carbon fiber three-dimensional braided preform (3D-B Cf) reinforced silicon carbide (SiC) with carbon and alumina (Al_2O_3) interphases were studied. Precursor pyrolysis, phenolic resin pyrolysis, and sol-gel were adopted to prepare SiC matrix, carbon and Al_2O_3 interphases respectively. The density and flexural strength of the composite with carbon interphase reached 1.80g/cm~3 and 360.0MPa, while those with Al_2O_3 interphase 1.91g/cm~3 and 428.4MPa, respectively. Al_2O_3 interphase effectively alleviates thermal mismatch between fiber and matrix, decreases interface bonding strength, therefore enhances strength and improves toughness. The composites with carbon interphase showed a typical brittle fracture mode.