title: Temperature and strain-rate dependence of surface dislocation nucleation.
abstract: Dislocation nucleation is essential to the plastic deformation of small-volume crystalline solids. The free surface may act as an effective source of dislocations to initiate and sustain plastic flow, in conjunction with bulk sources. Here, we develop an atomistic modeling framework to address the probabilistic nature of surface dislocation nucleation. We show the activation volume associated with surface dislocation nucleation is characteristically in the range of 1-10b3, where b is the Burgers vector. Such small activation volume leads to sensitive temperature and strain-rate dependence of the nucleation stress, providing an upper bound to the size-strength relation in nanopillar compression experiments.
authors.affiliation: Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA. ting.zhu@me.gatech.edu
authors.forename: Ting
authors.initials: T
authors.lastname: Zhu
authors.forename: Ju
authors.initials: J
authors.lastname: Li
authors.forename: Amit
authors.initials: A
authors.lastname: Samanta
authors.forename: Austin
authors.initials: A
authors.lastname: Leach
authors.forename: Ken
authors.initials: K
authors.lastname: Gall