The effect of dislocation-point defect interactions on rate processes in metals

At steady state during irradiation, since vacancies and interstitials are produced in equal numbers, they must disappear in equal numbers. A net difference in atomic fluxes for a particular type of sink can occur only if there is at least one other type of sink present and then only if one sink preferentially absorbs either vacancies or interstitials. Of course, if one type of sink receives an excess of interstitials, it follows that a second type of sink must receive an excess of vacancies. (Recombination, which will be ignored here, always removes equal numbers). Thus the magnitude of the differential flux must depend on the relative sink strengths of at least two types and, in particular, there can be no differential flux if only one type of sink is present. However, most estimates of these differential fluxes have been based upon mathematical models which contain only one type of sink, for which there can be no differential fluxes. This difficulty has been circumvented in basically two different ways, which are discussed. (author)