Buckling and Post-Buckling of Cantilevered Single-Walled Carbon Nanotubes in Bending
Abstract
There are various potential applications in which carbon nanotubes (CNTs) may be subjected to bending in a cantilevered configuration leading to buckling which in turn may affect their electrical, electronic as well as load bearing properties. Using atomistic simulations, we study buckling and post-buckling behavior of six single-walled CNTs subjected to bending in cantilever loading (i.e., flexure in addition to shear and axial compression). Starting with small kinks on the compression side corresponding to locations of high strain energy density, ripples form on the tube wall as bending progresses, until the tube flattens maximally at a critical location giving rise to a stable hinge that rotates under continued bending. The critical buckling curvature, locations of initial and stable hinges and rotational properties of the hinge are determined. Beyond the linear elastic region, the rotational stiffness depends on the hinge angle dropping close to zero (at the same angle for each tube) before beginning to rise again, reminiscent of snap-through buckling of shells, a property that can be exploited for sensing and signal amplification applications.
