A (10, 0) SWCNT of length 42.59 Å and aspect ratio 10.9 is studied by Molecular Dynamics (MD) simulation both in perfect condition and also with one, two, three or four SW defects introduced into them in different positions. Brenner’s bond order potential has been used for energy minimization. The Young’s modulus of a perfect (10, 0) SWCNT is found to be 1.06 TPa and the tensile strength is 141.7 GPa. A perfect CNT in our calculation fails at 18% strain. For different positions of a single defect in the tube, the tensile strength ranges from 103.59-127.71 GPa. Y value is reduced by upto 23%. More variation is obtained after the inclusion of 2 defects. Different (z, r, θ) combinations for double defect positions yield a minimum tensile strength of 82.31 GPa for diagonally situated defects. Three and four diagonal defects reduce the strength to 89.6 GPa. Fracture patterns show differences in their initiation points. Necking is observed in all cases and several breaking of bonds are observed surrounding the defect. Values calculated by us is close to the experimental values of 1.28 TPa for Young’s modulus and 150 GPa for failure stress.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2010: Advanced Materials, CNTs, Particles, Films and Composites
Published: June 21, 2010
Pages: 215 - 218
Industry sector: Advanced Materials & Manufacturing
Topics: Carbon Nano Structures & Devices