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A new extension of the self-consistent mean field (SCMF) theory is developed to describe diffusion in dilute alloys, special attention being paid to the problem of self-diffusion in the presence of solute atoms. We start from a microscopic model of the atom-vacancy exchange frequency including nearest neighbour (nn) interactions and derive kinetic equations from a Master equation. The non-equilibrium distribution function is expressed through time-dependent effective interactions. Their range of interaction is controlling the level of description of the paths of a vacancy after a first exchange. In contrast to the previous diffusion models devoted to concentrated alloys, the present formulation makes appear into the final result several exchange frequencies associated to a given atom depending on the chemical species of the atoms nearby. A first approximation restricted to nn effective interactions yields analytical …