A model for shrinkage of a spherical void in the center of a grain: Influence of lattice diffusion

A model is presented to describe a spherical void shrinkage at the center of a quasi-spherical grain dominated by lattice self-diffusion. The model is based on the difference in chemical potential between the spherical void surface and the grain boundary interface. The quantitative calculations for pure iron predicted that only small, micron-sized spherical voids could be wholly healed within hours at high temperature. The spherical void shrinkage process can be greatly promoted with an increase in temperature, which depends strongly on crystal lattices, particularly the initial radius of the spherical void and the grain size. The time to eliminate a spherical void with an identical radius within grains is close to that for grain boundaries, while different shrinkage processes were undergone, at fixed temperatures, and related to spherical void size, void spacing, and the grain size.