An XPS study of the elemental enrichment on aluminum alloy surfaces from chemical cleaning

The native oxide structure on aluminum alloys is usually modified by chemical treatments prior to the application of corrosion resistant coatings to increase adhesion and performance. Certain commercial modifications were studied to determine their effects on the alloy surfaces, which might have substantial implications on the interface between the alloys and plasma polymers deposited on them. An X-ray photoelectron spectroscopy (XPS) depth profiling investigation of the effects of these chemical cleaners revealed enrichments of alloying elements on the metal surface beneath the modified oxide. Aspects of the enrichment phenomena showed a correlation with data from corrosion-performance testing of interface engineered corrosion protection systems. The authors would like to acknowledge the support of DARPA through the US Air Force contract # AF F33615-96-C-5055.