The effect of a non-chromate deoxidiser (bromate-nitric acid) on AA2024-T3 has been examined by SEM, TEM/EELS and XPS. At low temperatures (20 degrees C) the deoxidiser removed all intermetallics but had little effect on the surface oxide. At 40 degrees C, attack on the intermetallics was again extensive but there was also evidence of attack on the surface oxide covering the matrix after 10 min of immersion, leaving a roughened porous oxide. At 60 degrees C, removal of intermetallics was complete and longer immersion times resulted in a characteristic scalloped structure across the surface which became more pronounced with increasing immersion time. Crown Copyright (C) 2007 Published by Elsevier B.V. All rights reserved.