Deformation mechanism of amorphous/crystalline phase-separated alloys: A molecular dynamics study

Abstract In this paper, molecular dynamics simulations have been performed to explore the deformation mechanism of amorphous/crystalline Cu50Ag50 phase-separated alloys with different crystal fractions during compressive deformation. Our findings indicate that as the crystal fractions increase, the yield strength also increases and there is a conspicuous strain-hardening phenomenon, especially for samples with a large crystal fraction. The cross-interaction of immature shear bands (ISBs) in different directions in crystals will hinder the extension and expansion of each other, resulting in a “strain-hardening”. Moreover, the shear-induced growth and the dissolution of the nanocrystals within the shear bands are observed. Structural transformation from body-centered cubic structure to face-centered cubic or hexagonal close-packed structures is induced by deformation. These atomic-scale observations reveal a novel deformation mechanism that can effectively improve the mechanical properties of metallic glasses.