The effect of cerium oxide argon-annealed coatings on the high temperature oxidation of a FeCrAl alloy

• Published in: Applied surface science Vol. 255; no. 23; pp. 9480 - 9486
• Main Authors: Nguyen, C.T., Buscail, H., Cueff, R., Issartel, C., Riffard, F., Perrier, S., Poble, O.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.09.2009; Elsevier
• Subjects: Alumina; Cerium; Cold working, work hardening; annealing, post-deformation annealing, quenching, tempering recovery, and crystallization; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; FeCrAl alloy; In situ X-ray diffraction; Materials science; Oxidation; Physics; Sol–gel coating; Structure and morphology; thickness; Surface treatments; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thin film structure and morphology; Treatment of materials and its effects on microstructure and properties; Cerium; Oxidation; FeCrAl alloy; Alumina; Sol–gel coating; In situ X-ray diffraction; Aluminium oxide; Scanning electron microscopy; Annealing; Inorganic compounds; Sol-gel coating; In situ; X-ray spectra; XRD; Cerium oxide; Coatings; Dispersive spectrometry; Surface structure; Rare earths; Argon; Thermal cycling; Sol-gel process
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2009.07.069

Ceria coatings were applied in order to improve the adherence of alumina scales developed on a model Fe–20Cr–5Al alloy during oxidation at high temperature. These coatings were performed by argon annealing of a ceria sol–gel coating at temperatures ranging between 600 and 1000 °C. The influence of these coatings on the alloy oxidation behaviour was studied at 1100 °C. In situ X-ray diffraction (XRD) was performed to characterize the coating crystallographic nature after annealing and during the oxidation process. The alumina scale morphologies were studied by means of scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). The present work shows that the alumina scale morphology observed on cerium sol–gel coated alloy was very convoluted. On the cerium sol–gel coated alloy, argon annealing results in an increase of the oxidation rate in air, at 1100 °C. The 600 °C argon annealing temperature results in a good alumina scale adherence under thermal cycling conditions at 1100 °C.