Tensile properties and damage evolution in a 3D C/SiC composite at cryogenic temperatures

Tensile test was used upon a 3D-C/SiC composite under air or nitrogen atmosphere to characterize its mechanical behaviors and associated damage evolutions from room to cryogenic temperatures. The tensile strength relatively weakened most at -40 °C, however, that is recovered as temperature decreasing to -100 °C. The mismatch of coefficient of thermal expansions between carbon fiber and SiC matrix plays a role in this mechanical response. An interfacial damage model based on microscopic observation is proposed. Finite element method is used to analysis C/SiC deformations. Some generalizations were provided under the cryogenic environment.