Role of nanocrystals on the plasticity of amorphous alloy

The role of nanocrystals on the plasticity of the Cu₆₄Zr ₃₆ amorphous alloy was studied in terms of the initiation of shear bands and the propagation of cracks. The plastic deformation behaviors of the fully amorphous and the partially crystallized samples with various degrees of crystallinity were compared. The partially crystallized alloys with an adequate amount of nanocrystals showed a considerable enhancement in their plasticity. Finite element calculations were conducted to qualitatively examine the role of the nanocrystals on the formation of the shear bands, while high-resolution electron microscopy was used to directly observe the crack propagation behavior through the matrix with (or without) nanocrystals.