Influence of nitridation on the oxidation of a 304 steel at 800 °C Christophe Issartel a, * , Henri Buscail a , Eric Caudron a , Regis Cueff a , Fr ederic Riffard a ,Sebastien Perrier a , Philippe Jacquet b , Michel Lambertin b a Laboratoire Vellave sur l’Elaboration et l’Etude des Materiaux, 8 rue J.B. Fabre––BP 219, 43006 Le Puy en Velay, France b LaBoMap, ENSAM, C.E.R., Cluny 71250, France Received 10 March 2003; accepted 29 January 2004 Available online 16 March 2004 Abstract This paper presents a study on the oxide growth on a AISI 304 chromia-forming alloy, in air at 800 °C. After the nitridation treatment was performed on the steel surface, a c N solid solutionisdetected.Inthiscase,nonitrideformationinthealloysurfacecouldbeobserved.In situ X-ray diffraction has been used to follow the oxides evolution at testing temperature. At the beginning of the oxidation test, CrN is formed together with Fe 2 O 3 . Nevertheless, Cr 2 O 3 quickly appears and leads to a protective oxide scale formation growing according to a para- bolicratelaw.DuringoxidationinsituX-raydiffractionalsoshowsthatFe 2 O 3 is transformed into FeCr 2 O 4 . Our results show that nitridation increases the high temperature oxidation resistance of 304 steels at 800 °C. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: A. Stainless steel; B. Nitridation; In situ X-ray diffraction; C. Oxidation; High temperature corrosion * Corresponding author. E-mail addresses: issartel@iut.u-clermont1.fr (C. Issartel), buscail@iut.u-clermont1.fr (H. Buscail), caudron@iut.u-clermont1.fr (E. Caudron), cueff@iut.u-clermont1.fr (R. Cueff), riffard@iut.u-clermont1.fr (F. Riffard), perrier@iut.u-clermont1.fr (S. Perrier), lambertin@cluny.ensam.fr (M. Lambertin). 0010-938X/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.corsci.2004.01.018 www.elsevier.com/locate/corsci Corrosion Science 46 (2004) 2191–2201