Prediction of dislocation cores in aluminum from density functional theory.
The strain field of isolated screw and edge dislocation cores in aluminum are calculated using density-functional theory and a flexible boundary condition method. Nye tensor density contours and differential displacement fields are used to accurately bound Shockley partial separation distances. Our results of 5-7.5 A (screw) and 7.0-9.5 A (edge) eliminate uncertainties resulting from the wide range of previous results based on Peierls-Nabarro and atomistic methods. Favorable agreement of the predicted cores with limited experimental measurements demonstrates the need for quantum mechanical treatment of dislocation cores.
Woodward
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Air Force Research Laboratory, Wright Patterson Air Force Base, Dayton, Ohio 45433-7817, USA.
Trinkle
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Hector
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Olmsted
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