Possible mechanism for Pb segregation at the solid-liquid aluminium interface

We have used a simple quasi-static model to study the microscopic behaviour of a Pb ion in the region of the solid-liquid interface of aluminium. Calculations make use of anab initio potential, not used before in the literature. The potential field experienced by the Pb ion has a characteristic structure, leading to anisotropic diffusion and segregation processes, depending on the orientation of the interface plane. This is qualitatively related to experimental findings.