Influence of mechanical stress on the growth of crystals

A review is presented of the author's rece4nt work on the influence of mechanical stress on the growth rate of materials. On the basis of the results, it is proposed that growth rate dispersion of secondary nuclei arises asa result of competition between stress reduction and dislocation enhancement of growth rates in the developing particles, with the former being the major influence at low particle sizes. The results are shown to account for the particle size and material dependence of the dispersion. Mechanistic studies suggest that the principal mechanism of stress reduction in growth rate is the influence of the applied stress on the surface free energy of the crystal. This effects both nucleation at the growth center and the migration of growth steps across the crystal surface.