Surface segregation in high-purity Al-100 ppm Pb foil annealed for 4 h at 540 degreesC 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. (C) 2002 Elsevier Science B.V. All rights reserved.