Determination of tensile strength distribution of nanotubes from testing of nanotube bundles

Single-walled carbon nanotube (SWNT) bundles are subject to tensile testing using a self-developed nano-mechanical testing device. The tensile strength of SWNT bundles, as well as reported data of multi-walled carbon nanotubes (MWNTs) and SWNT ropes, are studied by statistical approach. It is shown that the tensile strength distributions of carbon nanotubes (CNTs) or SWNT ropes can be adequately described by a two-parameter Weibull model. Considering the nonlinear elastic behavior of CNTs, a relation between individual CNT and CNT bundle strengths is studied, and a method for determining the tensile strength distribution of individual CNTs or CNT sub-bundles from experimental measurements on CNT bundles is proposed. Therefore the process for determining the strength distributions of individual CNTs can be greatly simplified by testing CNT bundles instead.