Abstract
The Order (N) Tight Binding Molecular Dynamics (TBMD) algorithms applied to\nsimulate the tensile elongations of short (2-2.5 nm) armchair and zigzag Single\nWalled Carbon Nanotubes (SWCNTs) without bond breakings or defect formation.\nSimulations are repeated at high temperatures. We fix the lower limit of\nbreaking strains to short SWCNTs without bond breaking or 5-7 defects\nformation. At room temperature, the simulated (4,4) SWCNT is able to carry the\nstrain up to 130% of the relaxed tube length without bond breaking or 5-7\ndefects formation. This value is 127% for (11,0) SWCNT, 125% for (17,0) SWCNT,\n123% for (10,10) SWCNT. In defect free, short nanotubes as the nanotube's\nradius increase the bond-breakings occur at lower strain values regardless of\ntheir chirality. This is true when we heat the tubes to higher temperatures.\nBond breaking strain values, tensile strength, Young's modulus of the SWCNTs\nare obtained as functions of temperature. Defect free zigzag nanotubes exhibit\nhigher tensile strength than armchaired ones. Young's modulus of defect free\nindividual singlewall nanotubes is found to be in the range of 0.400 TPa within\nthe elastic limit. At room temperature and experimentally realizable strain\nvalues, thinner tubes are more resistant to bond breaking and zigzag tubes over\narmchair ones. At high temperatures although the resistance to strain drops the\nsame trend still holds. We observe a slight decrease of the tensile strength\nwith increasing temperatures. The same trend is also observed in the Young's\nmodulus. Results are important in determining a true breaking strains of\nSWCNTs.\n