Role of core polarization curvature of screw dislocations in determining the Peierls stress in bcc Ta: A criterion for designing high-performance materials
نویسندگان
چکیده
We use a family of embedded atom model potentials all based on accurate quantum-mechanical calculations to study the relation between Peierls stress and core properties of the 1/2a^111& screw dislocation in bcc tantalum ~Ta!. We find that the Peierls stress (sP) is a function of the core-polarization curvature ~P! near the equilibrium core configuration. Our results suggest that the computationally available quantity P is a useful criterion for designing high-performance materials.
منابع مشابه
Calculating the Peierls energy and Peierls stress from atomistic simulations of screw dislocation dynamics: application to bcc tantalum
We introduce a novel approach to calculating the Peierls energy barrier (and Peierls stress) based on the analysis of the dislocation migration dynamics, which we apply to 1/2a〈111〉 screw dislocations in bcc Ta. To study the migration of screw dislocations we use molecular dynamics with a first principles based embedded-atom method force field for Ta. We first distinguish the atoms belonging to...
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