Unusual deformation mechanisms in carbon nanotube heterojunctions (5,5)–(10,10) under tensile loading

The Poisson's ratio effect of single wall carbon nanotube heterojunctions (HJ) of the type (5,5)–(10,10) is investigated using an hybrid finite element atomistic-continuum approach to simulate the mechanical behaviour of nanostructures. The nanotube HJs provide a peculiar deformation pattern, with combined bending and axial stretching of carbon nanotubes (CNTs), and a broad agreement of their axial stiffness with spring series continuum mechanics and existing molecular dynamics (MD) simulations. A possible auxetic behaviour is observed for the pure HJ with no tubes when subjected to tensile loading.