RBS analysis of rapidly solidified Al-Si-Ti alloy with Fe and Ni dopes

By means of Rutherford backscattering spectroscopy technique, a detailed element analysis of a rapidly solidified Al-9.6Si-0.8Ti (at%) alloy with Fe and Ni dopes has been investigated. It was found that the 0.02 μm thick surface layer of the ribbon is enriched with Si (24.0 at%) and Bi impurity (0.007 at%). Oscillations of non-uniformly Si depth distribution through the ribbon thickness were found at the ribbon surface layer (up to 0.2 μm in thickness). At the 140 °C annealing, Si atoms diffuse from the volume to the ribbon surface. Its concentration at the thin surface layer increases by 25%. At 500 °C, there is a redistribution of all alloy components. Dope elements diffuse into the ribbon volume, but Bi diffuses on the ribbon surface, reaching 0.06 at%. Si oscillations weaken, thickness of the layer in which they are detected extends to 0.4 μm.