Grain boundary-mediated plasticity accommodating the cracking process in nanograined gold: In situ observations and simulations

In this study, the underlying atomic-scale plastic deformation mechanisms responsible for crack propagation process in nanograined gold thin film with an average grain size of ~10 nm (ranging from ~2 to ~22 nm) is investigated by situ high-resolution transmission electron microscope observations (i.e., a homemade device atomic force inside microscope) and atomistic molecular dynamic simulations. The real-time results based on experimental simulations uncover consistently that accommodated boundary-mediated plasticity, which may result coalescence between neighboring nanograins. Furthermore, we find plasticity size-dependent, i.e., GB dislocation activities-induced rotation relative larger grains migration smaller comparison critical ~ 10 nm.