2008/03/07 by Paolo Moretti, Lasse Laurson, Mikko J. Alava +1 · 1 citation
Materials Science · Physics and Astronomy · #Crystallite #Deformation (meteorology) #Dislocation #Dislocation creep #Grain boundary #Grain boundary strengthening #High-Velocity Impact and Material Behavior #Microstructure and mechanical properties #Nonlocal and gradient elasticity in micro/nano structures #Plasticity #Stress field #cond-mat.mtrl-sci
paper · pdf · doi:10.1088/1742-5468/2008/05/p05010
published in Journal of Statistical Mechanics Theory and Experiment 2008(05), P05010 (Institute of Physics) · 13 pages, 5 figures
arxiv created 2008/03/07 · openalex publication_date 2008/05/22 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The dynamics of dislocation assemblies in deforming crystals indicates the emergence of collective phenomena, intermittent fluctuations and strain avalanches. In polycrystalline materials, the understanding of plastic deformation mechanisms depends on grasping the role of grain boundaries on dislocation motion. Here the interaction of dislocations and elastic, low-angle grain boundaries is studied in the framework of a discrete dislocation representation. We allow grain boundaries to deform under the effect of dislocation stress fields and compare the effect of such a perturbation to the case of rigid grain boundaries. We are able to determine, both analytically and numerically, corrections to dislocation stress fields acting on neighboring grains, as mediated by grain boundary deformation. Finally, we discuss conclusions and consequences for the avalanche statistics, as observed in polycrystalline samples.