Abstract
Three dimensional carbon/silicon carbide composites were prepared by chemical vapor infiltration, and the microstructure and the mechanical properties were investigated. For the composites (C/SiC) with no pyrolytic carbon interfacial layer, the mechanical properties (flexural strength, flexural elastic modules, shear strength, and fracture toughness) increase with the density of the composites. High density (ρ=2.1g·cm-3) C/SiC composites exhibit high fracture toughness (16.5 MPa·m1/2) but brittle fracture behavior because of strong bonding between fiber/matrix. Low density composites show non-catastrophic failure mode with long bundle pull-out. The composites (C/PyC/SiC) with pyrolytic carbon interfacial layer exhibit good mechanical properties and a typical failure behavior. Microstructural observations reveal that the tortuosity and bottleneck effect of the pores are two key issues which hinder the densification of composites.
Original language | English |
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Pages (from-to) | 73-76 |
Number of pages | 4 |
Journal | Key Engineering Materials |
Volume | 164-165 |
State | Published - 1999 |
Keywords
- C/SiC Composites
- Chemical Vapor Infiltration
- Mechanical Properties
- Microstructure