Microstructure and Mechanical Properties of Mesophase Pitch-based C/C Composites

With 3K PAN-based carbon fibers as reinforcing materials and with mesophase pitch as matrix precursor, mesophase pitch-based 2D carbon-carbon composites were obtained by pressure impregnation carbonization technology under different carbonization pressure. The morphology, flexural property and fractured surface were analyzed. The result shows that the morphology of matrix carbon changes with different carbonization pressure. The morphology shows small domains under low carbonization pressure, and domains under carbonization pressure respectively. The flexural strength and density of C/C composites increase with increasing carbonization pressure, and the flexural strength is up to 278MPa. The fractured characters of C/C are related to density and inferface bonding strength. The fractured surfaces are made of fracture and pulling out of fiber when the density is high and the bonding is moderate,materials have toughness character.