Control of shear band dynamics in Cu₅₀Zr₅₀ metallic glass by introducing amorphous-crystalline interfaces

Abstract

The effects of interfaces in crystalline Cu/amorphous Cu50Zr50 on shear banding dynamics are investigated using molecular dynamics simulations. The results show that the introduction of amorphous-crystalline interfaces can effectively promote the homogeneous distribution of shear transformation zones (STZs). We found that the high potential energy combined with the defects of the interfaces promote the nucleation of STZs. Further, the amorphous-crystalline interfaces are transition regions that mediate the transmission of dislocations in the crystallites into STZs in the metallic glasses. The accumulation of STZs and dislocations at the interfaces provide the sources for the enhanced plastic deformation in nanocomposites. These results allow us to determine the fundamental atomic structure of amorphous-crystalline interfaces in nanocomposites.