It was recalled that motion of a line-defect along an interface generally required a flux of material, and the magnitude of this flux depended upon the topological nature of the defect (Burgers vector, step height), the defect velocity and the atomic concentrations in the adjacent crystals. A mathematical expression was presented here which quantified the flux in terms of these parameters. Two situations arose: one in which defects separated crystallographically equivalent, so-called degenerate, regions of interface, and another in which they separated so-called distinct regions. The flux equation was slightly different for the 2 cases. Some examples of defect motion, and the resultant fluxes, were illustrated. The extent of mass transport which was associated with the interaction of pairs of interfacial defects was also addressed.

Mass Transport Associated with the Motion and Interaction of Line-Defects in Interfaces. T.Nixon, R.C.Pond: Solid State Phenomena, 1998, 59-60, 201-20