Dynamics of shear localization and stress relaxation in amorphous Cu_(50)Ti_(50)

摘要

Dynamic heterogeneities in metallic glasses are investigated for the model glass Cu_(50)Ti_(50) with the help of classical molecular dynamics computer simulations. By rapid quenching from melt at various cooling rates (spanning five orders of magnitude), differently relaxed amorphous cells are prepared. During subsequent shearing at T = 10 K, we observe a series of highly localized shear events, termed shear transformation zones (STZs). Detailed analysis focuses on the dynamics of STZ formation and the correlation with local properties. We identify a local mechanical stress bias as the physical origin of STZ formation during low-temperature shear deformation.