Background: This manuscript deals with identifying the fracture pattern in defective Double
Walled Carbon Nanotubes (DWCNT). It has been projected in a number of published papers that
CNTs always possess defects like vacancies in their structure, hence this type of analysis is helpful in
studying the pattern of fracture when subjected to tensile and other types of forces.
Method: Molecular structural mechanics approach is used to model the defective DWCNT and finite
element method is used to simulate the responses of the non-linear force field of the C–C bonds for
analysing the systematic fracture in double walled carbon nanotube structure with beam elements. The
model has been studied with reference to arm chair and zigzag DWCNTs with an atomic vacancy and
exposed to critical tension. The defect presented here (model) is one lacking atom at the outer tube of
the double walled carbon nanotube.
Results: The failure pattern is found to be different in all the two types of DWCNTs mainly because
of the orientation of the covalent bond between carbon - carbon atoms. This orientation further leads
to the change in the stiffness of the bonds which further leads to increase in the stress at the junction
and later on failure of the tube. The type of pattern evaluated in this manuscript has not been studied
previously in DWCNTs.
Conclusion: Catastrophic failure took place after fifteen consecutive iterations, for zigzag and armchair
of DWCNT. It shows that Zigzag DWCNT ((14,0)@(8,0)) has better strength compared to Arm
chair DWCNT ((8,8)@(6,6)).