B. Naboulsi et al., THERMAL-OXIDATION OF SOLAR SELECTIVE SURF ACES BASED ON FE-CR-AL OXIDES, Revue Internationale des Hautes Temperatures et des Refractaires, 29(3), 1994, pp. 69-88
Thermal oxidation of solar selective surfaces based on Fe-Cr-Al oxides
. The thermal behaviour of selective optical coatings in the air was s
tudied up to 900-degrees-C by optical methods, electro-chemical impeda
nce spectrometry, SIMS, ESCA/XPS and RHEED. Up to 700-degrees-C, these
coatings obtained from refractory steel containing aluminium present
stable thermoptical properties. The thickness and the texture remain a
pproximately the same. The diffusion of oxygen is restricted to the co
ating. The chromium-aluminium substituted magnetite which is the main
component of the coating and the hematite which appears beyond 200-deg
rees-C present substitution rates increasing with the temperature. Aro
und 600-degrees-C, iron titanate appears. Beyond 700-degrees-C, the em
issivity increases. The thickening of the coating and the strong modif
ication of the texture and composition are linked to substrate oxidati
on.