A general equation was developed for the treatment of this problem. In the case of a stationary grain boundary, the boundary did not deform and the general equation reduced to the well-known grain-boundary diffusion equation. In the case of a moving straight grain boundary, with the migration direction perpendicular to the boundary, the sum of the principal curvatures was zero. The general equation again reduced to the usual equation, but with modified fluxes at the boundary. It was noted that the derivation was also applicable to surface diffusion, where changes in surface area might need to be considered.

Grain Boundary Diffusion Equation at a Deforming Grain Boundary F.Yang: Scripta Materialia, 1998, 39[6], 771-3