Basal 〈a〉 dislocation-{[formula omitted]} contraction twin interactions in magnesium

Abstract

Basal 〈a〉 dislocation-{1¯011} contraction twin interactions are studied in magnesium using molecular dynamics simulations. It is shown that when a basal 〈a〉 dislocation interacts with a (1¯011) twin boundary, a stacking fault forms along the (101¯1) plane because the basal plane of the matrix is nearly parallel to the pyramidal plane of the twin with a deviation of 5.7°. After the second lattice dislocation enters the boundary, the faulted region is erased due to dislocation slip and atomic shuffle. Furthermore, when a basal 〈a〉 dislocation moves toward the lateral side of the twin, de-twinning occurs through a pure-shuffle mechanism.