Atomic picture of elastic deformation in a metallic glass

XD Wang and S Aryal and C Zhong and WY Ching and HW Sheng and H Zhang and DX Zhang and QP Cao and JZ Jiang, SCIENTIFIC REPORTS, 5, 9184 (2015).

DOI: 10.1038/srep09184

The tensile behavior of a Ni60Nb40 metallic glass (MG) has been studied by using ab initio density functional theory (DFT) calculation with a large cell containing 1024 atoms (614 Ni and 410 Nb). We provide insight into how a super elastic limit can be achieved in a MG. Spatially inhomogeneous responses of single atoms and also major polyhedra are found to change greatly with increasing external stress when the strain is over 2%, causing the intrinsically viscoelastic behavior. We uncover the origin of the observed super elastic strain limit under tension (including linear and viscoelastic strains) in small-sized MG samples, mainly caused by inhomogeneous distribution of excess volumes in the form of newly formed subatomic cavities.

Return to Publications page