The influence of surface treatments in hot acid solutions on the corrosion resistance and oxide structure of stainless steels L.V. Taveira a , G. Frank b , H.P. Strunk b , L.F.P. Dick a, * a Department of Metallurgy, Federal University of Rio Grande do Sul, Av. Osvaldo Aranha 99-615a, 90035-190 Porto Alegre, Brazil b Institute for Microcharacterization, University of Erlangen, Cauerstrasse 6, 91058 Erlangen, Germany Abstract The effect of anodic treatments on the corrosion resistance in Cl  -solutions and the struc- ture of oxide layers on alloy AISI304 was investigated. Oxides were analysed using RBS, SEM and TEM. The highest pitting potential shifts (790 mV) are obtained by anodizing at high tem- perature (95 °C) within the passive range in acid baths. Using this method it was possible to grow oxides layers up to 400 nm, that are constituted of porous nanocrystalline spinel. Mo and Nb are incorporated into the oxide layer but have no benefit on the improvement of corrosion resistance, which is explained by greater thickness and Cr-enrichment of the oxide layer. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Stainless steels; Surface treatments; Anodization; TEM; Pitting corrosion 0010-938X/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.corsci.2004.07.012 * Corresponding author. Tel.: +55 51 33163299; fax: +55 51 33163988. E-mail address: lfdick@vortex.ufrgs.br (L.F.P. Dick). Corrosion Science 47 (2005) 757–769 www.elsevier.com/locate/corsci