Fig. 4

Atomistic simulation of dislocation interaction with a Ta nanocluster. a A schematic of the simulation of the interaction between an edge dislocation and a Ta nanocluster in a single Cu nanocrystal where X, Y, and Z correspond to the \(\left[ {1\bar 10} \right]\), [111], and \(\left[ {11\bar 2} \right]\) directions, respectively, and atomistic simulation results showing an edge dislocation interacting with a Ta nanocluster in a Cu nanocrystal. The red atoms represent the stacking fault region of the dislocation in Cu, the blue atoms represent the Ta nanocluster, and the green atoms represent the boundaries of the crystalline Cu atoms. b Dislocation velocity as a function of applied shear stress for an edge dislocation in nanocrystalline Cu both with and without an embedded Ta nanocluster for 100 K. Here, L is the dislocation line length, D is the diameter of the Ta nanocluster, and S is the distance between the dislocation and Ta nanocluster. Note that for 300 K, the dislocation is instantaneously pinned by the nanocluster at values of S up to 6 nm without any externally applied stresses. c Comparison of phonon density of states for pure Cu and Cu embedded with a Ta nanocluster at both 300 and 473 K