Abstract
We improved the method of measuring method of interdiffusion coefficients using the Foton shear cell technique and stable density layering by adding the normalization of the measured concentration, reducing the segregation in the alloys, and improving the fitting method of the theoretical diffusion formula. We measured interdiffusion coefficients of Sn-Pb alloys using two different diffusion pairs (Sn and Sn-10at%Pb, Pb and Pb-10at%Sn) at 773K and investigated the dependence of diffusion coefficients on the solute concentration. The measured values agreed well with the theoretical curve obtained using Darken’s equation. Therefore, we supposed that Darken’s equation is also applicable to diffusion in liquid.