Corrosion behaviour of Ni and nickel aluminide coatings exposed in a biomass fired power plant for two years

SURFACE & COATINGS TECHNOLOGY

卷:362

Article

Wu, D. L.^1,2  Dahl, K., V²  Christiansen, T. L.²  Montgomery, M.²  Hald, J.² 

[1] Yangzhou Univ, Coll Mech Engn, Yangzhou 225127, Jiangsu, Peoples R China

[2] Tech Univ Denmark, Dept Mech Engn, DK-2800 Lyngby, Denmark

关键词: Ni coating;    Ni2Al3 coating;    Biomass combustion;    Power plant testing;    Fireside corrosion;   

DOI  :  10.1016/j.surfcoat.2018.12.129

来源: Elsevier

【 摘 要 】

Ni and Ni2Al3 coatings were applied to superheater tubes that were built into a wood-fired boiler with an outlet steam temperature of 520 degrees C. The present paper evaluates the performance of the coatings after two years of service. The corrosion performance of the coatings is discussed with respect to the temperature histograms and deposit composition and compared to the performance of the coatings after the first year. The Ni coatings showed extremely protective behaviour for 1 year however after 2 years exposure, the Ni coating was chemically attacked, thick NiO was formed and sulphur containing precipitates were present at the base of the Ni layer indicating grain boundary ingress of corrosive species. For the Ni2Al3 coatings, localized attack was observed after the first year of exposure, but after two years no intact nickel aluminide coatings were observed.

【 授权许可】

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