Keywords

anisotropic, Edge dislocation, eleasticity theory, equilibrium core structures, Johnson potential, plane strain

Abstract

The authors are pleased to acknowledge: the support of this research by the National Science Foundation under Grant DMR 74-21243 and by the provision of computer time by The Ohio State University and by Battelle Columbus Laboratories; and helpful comments on the manuscript by V Vitek. Computer simulation is used to obtain the plane strain and non-plane strain equilibrium core structures for the a/2 <111> {110} edge dislocation in alpha-iron as modelled by the Johnson potential. The methods of the integral formulation of anisotropic linear eleasticity theory are employed in the analysis. Flexible core boundary methods reveal that positive volume expansions of 0.57b2 and 0.62b2 result from introduction of the dislocation (plane and non-plane strain cases respectively) into the perfect lattice. The non-plane strain relaxation reveals significant displacement parallel to the dislocation line in the compressive near-core region. This effect arises as a consequence of the strong nonlinearity of the core region elastic field.

Original Publication Citation

J. Phys. F: Metal Phys., Vol. 7, No. 1, 1977