Flexural Properties of Pitch-based Carbon/Carbon Composites

Flexural properties of unidirectional carbon fiber reinforced pitch-based carbon/carbon (C/C) composites (1D-C/C) and 3D(dimension) & 4D (direction) braided carbon fiber reinforced pitch-based C/C composites (3D-C/C) were tested by three-point bending beams at room temperature and 1 800 ℃ respectively.Effects of reinforcement structures and temperatures on flexural properties of the pitch-based C/C composites were analyzed,and the interface mechanisms in flexural failures was discussed.The results show that the flexural modulus of 3D-C/C was higher than that of 1D-C/C,while the flexural strength of 3D-C/C was lower than that of 1D-C/C obviously.The flexural failure of 1D-C/C was brittle,but that of 3D-C/C was pseudoplastic.Flexural properties of the pitch-based C/C composites at 1 800 ℃ were more excellent than those of the pitch-based C/C composites at room temperature.