BRITTLE AND DUCTILE BEHAVIOR IN CARBON NANOTUBES

Large-scale molecular dynamics simulations were used to study the resp onse of carbon nanotubes to a tensile load. Plastic or brittle behavio rs can occur depending upon the external conditions and tube symmetry. All tubes rule: brittle at high strain and low temperature, while at low strain and high temperature: armchair (tl,rr) nanotubes can be com pletely or partially ductile. In zigzag (n,0) tubes ductile behavior i s expected for tubes with n < 14, while larger tubes are completely br ittle. In both cases the curvature determines the mechanical response. [S0031-9007(98)07696-0].