Surface Energy of a 90° Domain Wall in Iron

Abstract

The relative surface energy of a 90° domain wall in a cubic material with K1>0 (iron) has been evaluated over the range of possible wall orientations. As the plane of the wall passes through a {110} plane, the minimum-energy configuration changes from a right-hand to a left-hand rotation of the atomic moments; this leads to a sharp upward cusp in the energy vs orientation curve. The calculated orientation dependence of the surface energy can be used to predict a stable wall position in an iron whisker. The prediction is in reasonable agreement with observation.