Segregation of lead in oxide film of high-purity aluminum containing 100 ppm lead

Surface segregation in high-purity Al–100 ppm Pb foil annealed for 4 h at 540 °C was studied mainly by transmission electron microscopy (TEM) observations. TEM–EDX demonstrated that almost of the lead element segregated not to aluminum surface but predominantly to the oxide amorphous film formed just above aluminum surface. The enrichment of lead in the oxide film was about 30 000 fold.