Xiaohan Zhang's blog
A Continuum Model for Dislocation Pile-up Problems (Accepted by Acta Materialia)
A continuum dislocation pile-up model is developed to solve problems with arrays of edge dislocations on one or multiple slip planes. The model solves pile-up problems in a discrete dislocation dynamics manner. The effect of anisotropy and stacking fault energy can be naturally modeled. The model is validated by reproducing the solutions of problems for which analytical solutions are available. More complicated phenomena such as interlacing and randomly distributed dislocations are also simulated.
A single theory for some quasi-static, supersonic, atomic, and tectonic scale applications of dislocations
Xiaohan Zhang Amit Acharya Noel J. Walkington Jacobo Bielak
We describe a model based in continuum mechanics that reduces the study of a significant class of problems of discrete dislocation dynamics to questions of the modern theory of continuum plasticity. As applications, we explore the questions of the existence of a Peierls stress in a continuum theory, dislocation annihilation, dislocation dissociation, finite-speed-of-propagation effects of elastic waves vis-a-vis dynamic dislocation fields, supersonic dislocation motion, and short-slip duration in rupture dynamics.