Elastic constants of achiral single-wall CNTs: Analytical expressions and a focus on size and small scale effects

Abstract

Abstract The paper presents a study of defect-free achiral single-wall CNTs starting from a simple and effective molecular mechanics model (stick-and-spring), accounting for binary and ternary interactions at the atomic scale. The analytical expressions of the elastic constants related to the membrane behaviour of a Donnell thin shell are derived exploiting proper discrete homogenization tools and the results are compared with those of numerical analyses of the tubes under tensile, radial and torsional loads. By the analysis of the results, size and small scale effects are clearly highlighted and a discussion about their relevance is carried out.