On the critical thickness for non-localized to localized plastic flow transition in metallic glasses: A molecular dynamics study. (15th March 2016) - Zhong, C.
Abstract: Molecular dynamics simulations were employed to investigate the specimen thickness-dependent tensile behavior of a series of Cu x Zr100- x ( x = 20, 40, 50, 64 and 80 at.%) metallic glass (MG) films, with a particular focus on the critical thickness, t c, below which non-localized plastic flow takes place. The simulation results reveal that while the transition occurs in all the alloys examined, t c is sensitive to the composition. We rationalize t c by postulating that the strain energy stored in the sample at the onset of plastic deformation has to be sufficient for the formation of shear bands. The composition-dependence of t c was found to correlate with the average activation energy of the atomic level plastic deformation events.