Interaction of dislocations and shear bands in cutting of an amorphous-crystalline bilayer: An atomistic study

Composites of crystalline and amorphous metals combine high strength with ductility. Using molecular dynamics simulation, we analyze the plastic processes occurring at the interface of a bilayer system consisting of a crystalline Cu and an amorphous CuZr sample. When cutting this bilayer parallel to the interface, a top glass layer forms a series of parallel shear bands, while a top crystal layer deforms by the coordinated action of dislocation activity. Zones of localized shear strain ? dislocations in the crystal and shear bands in the glass ? arriving at the interface may transport the localized strain through it by exciting dislocations and shear bands on the other side of the crystal. In particular, dislocations in the underlying crystal trigger a more homogeneous deformation in the top glass layer as compared to cutting a pure glass.