Atomic mechanisms governing upper limit on the strength of nanosized crystals

The goal of this research is to present ideas on mechanisms governing the strength of nanosized crystals (NSC) and to estimate on this basis maximum attainable for them levels of strength. Findings of experimental measurement of strength of metallic nanoneedles and carbyne (one-dimensional carbon crystal, which strength two times exceeds strength of graphene) are also presented. Based on the results of MD-simulation and ab initio calculations, it is exhibited that local instability of the lattice is the main mechanism governing the magnitude of strength of defect-free NSC, it temperature dependence and size effect. Regularities of dimensionality effect (growth of strength at transition from 3D to 2D and 1D crystals) are obtained and it explanation is given.