Influence of heat treatment on the internal friction of 2D-C/SiC composites

The internal friction of two-dimensional C/SiC composites (2D-C/SiC) was investigated in air by means of three-point bending forced vibration, compared with the specimens after heat treatment. The result shows that the effects of PyC interface between carbon fibers and SiC matrix play an important role on the internal friction characters of 2D-C/SiC composites, which leads to some unique internal friction phenomena in 2D-C/SiC composites. After the heat treatment, the PyC interface produces damage that make internal friction increased and dynamic modulus decreased. The heat treatment makes the internal friction of 2D-C/SiC composites more insensitive to temperature and frequency, and more sensitive to amplitude.