Mechanical response and failure of 3D MWK carbon/epoxy composites at cryogenic temperature

摘要: Static tensile and bending experiments are conducted on 3D MWK carbon/epoxy composites with two types of fiber architecture at room cryogenic temperature (low as −196 ℃). Macro-Fracture morphology SEM micrographs examined to understand the deformation failure mechanism. The results show that stress vs. strain curves have linear elastic feature up failure; while load-deflection for large orientation angle pronounced nonlinear in steps. Meanwhile, properties liquid nitrogen been improved significantly. Moreover, can be affected greatly by these decrease increasing temperatures. also damage patterns vary temperature. main material A is 0 ° fibers fracture matrix cracking. mechanism B delamination, 90 °/+45 °/−45 fiber/matrix interface debonding tearing, well fibers’ breakage. At temperature, solidified interfacial adhesion between enhanced However, brittle becomes more obvious, microcracks propagate interpenetrate.