2003/12/16 by Paolo Moretti, M. Carmen Miguel, M. -Carmen Miguel +2 · 99 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Chemistry #Composite material #Compression (physics) #Condensed matter physics #Crystallography #Dislocation #Dislocation creep #Elasticity (physics) #Force Microscopy Techniques and Applications #Grain boundary #High Temperature Alloys and Creep #Materials science #Microstructure and mechanical properties #Physics #Slip (aerodynamics) #Stiffness #Tension (geology) #Thermodynamics #cond-mat.mtrl-sci #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevb.69.214103
published in Physical Review B 69(21) (American Physical Society) · 13 pages, 8 figures
arxiv created 2003/12/16 · openalex publication_date 2004/06/08 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We investigate the depinning transition occurring in dislocation assemblies. In particular, we consider the cases of regularly spaced pileups and low-angle grain boundaries interacting with a disordered stress landscape provided by solute atoms, or by other immobile dislocations present in nonactive slip systems. Using linear elasticity, we compute the stress originated by small deformations of these assemblies and the corresponding energy cost in two and three dimensions. Contrary to the case of isolated dislocation lines, which are usually approximated as elastic strings with an effective line tension, the deformations of a dislocation assembly cannot be described by local elastic interactions with a constant tension or stiffness. A nonlocal elastic kernel results as a consequence of long-range interactions between dislocations. In light of this result, we revise statistical depinning theories of dislocation assemblies and compare the theoretical results with numerical simulations and experimental data.