TY - JOUR AU - Habib, K. A. AU - Saura, J. J. AU - Ferrer, C. AU - Damra, M. S. AU - Cervera, I. PY - 2011/04/30 Y2 - 2024/03/29 TI - Oxidation behaviour at 1123 K of AISI 304-Ni/Al-Al2O3/TiO2 multilayer system deposited by flame spray JF - Revista de Metalurgia JA - Rev. metal. VL - 47 IS - 2 SE - Articles DO - 10.3989/revmetalmadrid.1003 UR - https://revistademetalurgia.revistas.csic.es/index.php/revistademetalurgia/article/view/1185 SP - 126-137 AB - The oxidation behaviour of alumina/titania (97/3, 87/13 and 60/40) ceramic coatings using a Ni-Al coupling layer was studied in a thermobalance. Both layers were deposited on an AISI 304 stainless steel base metal by the flame spray technique. The coated steel was heated from room temperature to 1,123 K at 40 K min <sup>–1</sup>, oxidized in air for 50 h, and then cooled to room temperature at 40 K min<sup>–1</sup>. The mass gain was mainly attributed to the oxidation of Ni-Al coupling layer. Kinetic laws, DW·S <sup>–1</sup> (mg.mm<sup>–2</sup>) vs. time (hours) were close to a parabolic plot for each sample. Surface composition of ceramic top layer and the cross section of multilayer system were analysed using a wide range of experimental techniques including Scanning Electron Microscopy (SEM), equipped with a link energy dispersive X-Ray spectroscopy (EDX) and X-Ray diffraction (XRD) before and after the oxidation process. Coatings 97/3 and 87/13 presented a stable structure after flame spray deposition and they did not evolve with the oxidation process, while most of the 60/40 coating changed to a metastable structure after deposition and to a more stable structure after oxidation with high micro-cracks content. SEM and EDX microanalysis of the cross-sections showed that significant oxidation and a weak intergranular precipitation had been produced in the coupling layer and on the stainless steel base metal, respectively. ER -