Carbon/ carbon composites were prepared by densifying through pregnation carbonization and graphiti
zation technology. The effect of volume fraction of pre oxidized fiber web on the mechanical performance of carbon/
carbon composites was studied by means of measuring the tensile strength,compression strength,flexural strength,
shear strength,and fracture morphology of sample was observed by using scanning electron microscope. The results
show that the mechanical performance in z direction (except compression strength) is increasing monotonously with in
crease of volume fraction of pre oxidized fiber web, and the mechanical performance in xy direction is little influenced
by volume fraction of pre oxidized fiber web. It is also found that the mechanical performance in z direction is closely
related to the amount and distribution of the fiber in z direction.