The enrichment of copper alloying additions near the surface of sputtering-deposited Al-1.3 at.%Cu, Al-2.7 at.%Cu and Al-30 at.%Cu alloys is investigated following immersion in nitric acid, which is used commercially as a de-smutting pre-treatment. Corrosion of the alloys is revealed at rates in the range 4-13 nm min(-1), leading to enrichment of copper in the alloy surface regions. Enrichments are also generated by nitric acid treatment of AA2024-T3 and AA7075-T6 alloys, with levels similar to those achieved by etching in sodium hydroxide solution. Conventional durations of de-smutting treatments in nitric acid have minor influences on the magnitude of enrichment. (c) 2008 Elsevier Ltd. All rights reserved.