Continuum Modeling of Stress-Driven Surface Diffusion in Strained Elastic Materials

The free energy of a deformable crystal is assumed to consist of elastic strain energy and surface energy, and the chemical potential for surface diffusion at constant temperature is obtained under this assumption. The result is applied in considering the phenomena of instability of a flat surface in a stressed material under fluctuations in surface shape, and the development of surface roughness due to the proximity of misfit dislocations to the free surface of the material.