Effect of Screening on Solute Diffusion in Metals

Abstract

A simple atomistic theory of solute diffusion in metals for cases of negligible chemical concentration gradients is discussed. Calculations are made, using a Thomas-Fermi approximation, of the influence of the presence of impurity atoms on the Fermi electrons of the lattice. The results are applied to the case of diffusion of Sb in Ag, and indicate that the screening terms are sufficient to explain the magnitude and direction of the observed deviation from self-diffusion in Ag for a vacancy mechanism for diffusion.