Coalescence of the voids in condensed medium

The kinetics of the coalescence initial stage for gas-filled pores after their contact (incubation period of swelling) being a part of studies dealing with fissionable and structural materials swelling a result of gas cavities coalescence with following growth of the new pore volume is discussed. A possible physical mechanism of the initial stage of gas cavities coalescence connected with disappearing the separating layer between pores due to surface self-diffusion is described. It is shown that equating of the coefficients of atom volume and surface diffusion takes place at high temperature. The conclusion is made that the volume of pores being in contact does not increase at the first stage. The pore growth up to a new equilibrium state connected with vacancies volume diffusion takes place in the course of the gas-filled pores coalescence second stage