A comment on ‘Crystallography and migration mechanisms of planar interface boundaries’ Acta Materialia, 52, 795–807 (2004) by J. F. Nie

Abstract

In a recent paper by Nie, it was claimed that there is no two-dimensional continuity of lattice planes across the invariant line. However, it is a property of an invariant line strain that any planes related by the transformation strain must exhibit continuity across the invariant line. This note indicates that the NieÕs incorrect conclusion is due to his definition of the shear strain that is different from the standard matrix method.

Structures in irrational singular interfaces

“…[16] This interface was also rationalized in terms of plane edge matching, [37] which is equivalent to the 2-D invariant line approach. [53] While the 2-D invariant line model has the advantage of providing a clear physical picture of the irrational interface, its application is limited by the special geometry between the steps and dislocations. Rotation around a pair of parallel Burgers vectors may result in a D I interface, but the invariant line is usually not normal to the rotation axis, as explained in a detailed analysis.…”