Direct Observation of the Deformation Mechanism of Twin-Structured Ni NWs under Bending Strain

In situ atomic-scale bending tests of twin-structured Ni nanowires were realised using a homemade deformation device. The results showed that the plastic deformation mechanism in twin-structured Ni nanowires depended on the deformation stage. At the early stages of bending deformation, the plasticity of twin-structured Ni nanowires was controlled by dislocations interacting with the twin boundaries or parallel to them. With increasing bending strain, both dislocation and face-centred cubic-body-centred tetragonal phase transition occurred. At very high bending strain, grain boundaries resulting from the lattice distortion/collapse were formed. This study details the deformation mechanisms of the twin-structured Ni nanowires under bending deformation, which advances the basic understanding of the plasticity mechanisms in metals.

Automated summary

This study investigates the deformation mechanisms of twin-structured Ni nanowires under bending deformation. It finds that plastic deformation is controlled by dislocations and phase transitions, leading to the formation of grain boundaries.