Mixed mode brittle fracture in epoxy/multi-walled carbon nanotube nanocomposites

The effects of multi-walled carbon nanotubes (MWNTs) on fracture behavior of epoxy under mixed mode I/II loading have been studied. A number of test specimens based on different contents of MWNTs were prepared and the fracture tests were carried out. The increase in fracture resistance of the nanocomposite depended on the mode mixity. To find the reason, the fracture mechanisms in different modes of fracture were studied by examination of the fracture surfaces. It was found that in addition to the mechanisms, which contribute in mode I fracture, some extra mechanisms participate in mixed mode and mode II loading.