Screw dislocation mobility in BCC Metals: a refined potential description for alpha-Fe

TitleScrew dislocation mobility in BCC Metals: a refined potential description for alpha-Fe
Publication TypeJournal Article
Year of Publication2011
AuthorsGordon PA, Neeraj T, Mendelev MI
Journal TitlePhilosophical Magazine
Volume91
Pages3931-3945
Date Published10
ISBN Number1478-6435
Accession NumberISI:000298584000006
Keywordsatomistic simulation, core structure, CU, defect, dislocation dynamics, dislocation theory, iron, model, plasticity, plasticity of metals, simulation, transition-metals
Abstract

In this work, we seek to develop a new interatomic potential for alpha-Fe that is able to rationalize experimental flow stress data. We generate a series of potentials with similar bulk and point defect properties, but exhibit different energetic landscapes for the Peierls potential. The family of potentials all possess a compact core structure, which we find necessitates a camel-hump shaped Peierls potential. Within this constraint, we analyze the relationships between the Peierls potential, the 3-D kink nucleation energetics, and the resulting shape of the kink structures for the 1/2 < 111 > {110} screw dislocation. We find that one of our models, labeled MPG20, gives very good agreement with experimental flow stress data over the entire stress range considered.

URL<Go to ISI>://000298584000006http://www.tandfonline.com/doi/pdf/10.1080/14786435.2011.597947
DOI10.1080/14786435.2011.597947
Alternate JournalPhilos Mag