Surface Segregation of Transition Elements in High-Purity Aluminum Foil

Surface segregation phenomena of several transition elements (Fe, Ni, Mn, Co, Cr) in high purity aluminum foils annealed at various temperatures were studied by Rutherford back scattering spectroscopy (RBS) and transmission electron microscopy (TEM). These all elements segregated at the foil surface and detail segregation position was the interface between aluminum oxide and matrix. The degree of surface segregation (α=surface segregation composition/foil composition) depended on the element, annealing temperature and initial foil composition. The empirical rule for the surface segregation was obtained in this study as follows: the maximum α of each element was roughly dependent on the inverse of solid solubility of each element in aluminum.