Fracture of vacancy-defected carbon nanotubes and their embedded nanocomposites
نویسندگان
چکیده
In this paper, we investigate effects of vacancy defects on fracture of carbon nanotubes and carbon nanotube/ aluminum composites. Our studies show that even a one-atom vacancy defect can dramatically reduce the failure stresses and strains of carbon nanotubes. Consequently, nanocomposites, in which vacancy-defected nanotubes are embedded, exhibit different characteristics from those in which pristine nanotubes are embedded. It has been found that defected nanotubes with a small volume fraction cannot reinforce but instead weaken nanocomposite materials. Although a large volume fraction of defected nanotubes can slightly increase the failure stresses of nanocomposites, the failure strains of nanocomposites are always decreased.
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