Effect of molybdenum on the oxidation resistance of FeCrAl alloy in lower temperature (400 °C) and higher temperature (1200 °C) steam environments

• Published in: Corrosion science 2024-04, Vol.229 (C), p.111870, Article 111870
• Main Authors: Qu, Haozheng J., Chikhalikar, Atharva S., Abouelella, Hamdy, Roy, Indranil, Rajendran, Rupesh, Nagothi, Bhavani S., Umretiya, Rajnikant, Hoffman, Andrew K., Rebak, Raul B.
• Format: Article
• Language: English
• Subjects: Accident tolerant fuels; FeCrAl alloys; Molybdenum; Nuclear cladding materials; Steam-oxidation
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2024.111870

The effect of 0, 1, 3 wt% Mo addition on the corrosion behavior of Fe21Cr5.5Al was studied through steam tests at 400 °C and 1200 °C. At 400 °C, Mo addition leads to non-protective Fe-Mo oxide growth on the surface, compromising protective uniform Cr oxide growth and subsequent Al2O3 layers as in the Mo-free specimen. At 1200 °C, the presence of Mo causes the spallation of the surface oxide scale. However, a thin alumina surface film was present. Current results show that Mo addition is detrimental to the corrosion resistance of FeCrAl alloy under both operational and accidental temperature scenarios. •Mo addition effect on FeCrAl oxidation behavior at 400 °C is studied for the first time.•Mo promotes non-uniform oxidation and forms loose oxide on FeCrAl at 400 °C.•Mo addition compromises Cr and Al oxide formation during 400 °C steam oxidation.•Mo oxide evaporates and spalls surface oxide completely in 1200 °C steam.•Mo addition is detrimental to steam oxidation resistance of FeCrAl alloy.