A Continuum Model For Stone-Wales Defected Carbon Nanotubes

In this paper, a continuum model is proposed so that a stone-wales (sw) defected carbon nanotube (cnt) is replaced by an initial circumferential crack in a continuum cylindrical shell. for this purpose, the critical energy release rate and then the fracture toughness of a defected cnt are calculated using the results of an existing atomistic-based continuum finite element simulation. finally, the equivalent crack length is obtained from the fracture toughness. the proposed model can be applicable tovarious kinds of continuum-based simulations of nano-structures like nano-composites and nano-probes where the fracture resistance studies become important. it is concluded for a case study that the armchair (12, 12) cnt containing a sw defect could be replaced with a continuum cylindrical shell with a circumferential crack length of 0.83 nm. furthermore, the damage variable is discussed to achieve a method for estimating the effective young's modulus of defected nanotubes with numerous defects subjected to the progressive damage. this estimation method is evaluated by the atomistic based fe simulation of a double defected cnt.