Mechanics of coiled nanotubes in uniaxial tension

The mechanics of coiled nanotubes in uniaxial tension is presented in simple explicit expressions. The estimations for double coils are obtained. Given the initial geometry, good agreement in the whole stretching process (about 30% elongation) is observed in comparison with the experimental result. In addition, it is found that as an alternative, the shear modulus of the tube can be determined by the uniaxial tensile test. However, the analysis reveals that it is difficult to precisely determine the Poisson ratio.