Anelasticity of twinned CuO nanowires

The mechanical behavior of CuO nanowires (NWs) was investigated by in situ transmission electron microscopy. During compression, the NWs exhibited high bending capabilities associated with high mechanical stress. Interestingly, anelasticity was consistently observed after stress release. Further investigations indicate that the anelasticity is intrinsic to the CuO NWs, although electronbeam irradiation was proved capable of accelerating the shape recovery. A mechanism based on the cooperative motion of twin-associated atoms is proposed to account for this phenomenon. The results provide insight into the mechanical properties of CuO NWs, which are promising materials for nanoscale damping systems.