Journal article
Breakdown mechanism of γ-Al2O3 on Ni2Al3 coatings exposed in a biomass fired power plant
In
Corrosion Science
—
2020, Volume 170, pp. 108583
Abstract
A Ni2Al3 coated tube was exposed in a wood firing power plant for 7100 h. The exposure resulted in protective behaviour in most areas, while corrosion attack occurred in local areas. In areas exhibiting protective behaviour, a 30−50 nm thick γ-Al2O3 layer was found, and a 200−250 nm K–O rich amorphous layer was identified in the corroded area.
A corrosion mechanism is suggested: γ-Al2O3 was broken down by reaction with KCl(g) resulting in formation of potassium aluminate. Migration of Cl through potassium aluminate resulted in formation of volatile AlCl3. KCl-AlCl3 then led to alumina fluxing and further corrosion attack.
| Language: | English |
|---|---|
| Year: | 2020 |
| Pages: | 108583 |
| ISSN: | 18790496 and 0010938x |
| Types: | Journal article |
| DOI: | 10.1016/j.corsci.2020.108583 |
| ORCIDs: | Wu, D. L. , Dahl, K. V. , Grumsen, F. B. , Christiansen, T. L. , Montgomery, M. and Hald, J. |
