Predicting Shear Transformation Events in Metallic Glasses

• Published in: Physical review letters 2018-03, Vol.120 (12), p.125503-125503, Article 125503
• Main Authors: Xu, Bin, Falk, Michael L, Li, J F, Kong, L T
• Format: Article
• Language: English
• Subjects: Amorphous materials; Computer simulation; Deformation; Mechanical properties; Metallic glasses; Plastic deformation; Potential energy; Predictions; Shear; Transformations
• ISSN: 0031-9007; 1079-7114
• DOI: 10.1103/PhysRevLett.120.125503

Shear transformation is the elementary process for plastic deformation of metallic glasses, the prediction of the occurrence of the shear transformation events is therefore of vital importance to understand the mechanical behavior of metallic glasses. In this Letter, from the view of the potential energy landscape, we find that the protocol-dependent behavior of shear transformation is governed by the stress gradient along its minimum energy path and we propose a framework as well as an atomistic approach to predict the triggering strains, locations, and structural transformations of the shear transformation events under different shear protocols in metallic glasses. Verification with a model Cu_{64}Zr_{36} metallic glass reveals that the prediction agrees well with athermal quasistatic shear simulations. The proposed framework is believed to provide an important tool for developing a quantitative understanding of the deformation processes that control mechanical behavior of metallic glasses.