Erosion-corrosion behavior of Ni-20Cr-4Fe and Ni-20Cr-4Fe-7Mo under fluidized-bed biomass boiler conditions. (15th August 2022)

• Record Type: Journal Article
• Authors: Yoneda, Suzue; Hayashi, Shigenari; Miyakoshi, Yasuki; Kogin, Takashi; Ishikawa, Eiji; Noguchi, Manabu
• Is Part Of: Corrosion science. Volume 205(2022)
• Publication Date: 2022-08-15
• Subjects: High-temperature erosion-corrosion -- Coating -- Fluidized-bed boiler; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110472
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: The erosion-corrosion rate of the Mo-free alloy decreased over time because of a reduction in the erosion rate of the oxide scale associated with the transition of the scale from Ni-rich to Cr-rich. In contrast, the Mo-containing alloys displayed accelerated erosion-corrosion because of the repeated erosion of Ni-rich oxide layer and spallation of the oxide scale. The volatilization of Mo oxychloride resulted in the formation of an inner porous oxide layer which results in enhanced spallation of the oxide scale by the impact of sand particles. These volatilization and spallation processes were found to enhance the erosion-corrosion of Mo-containing alloys. Highlights: The erosion rate of Cr-rich oxide was lower than that of Ni-rich oxide. The erosion-corrosion rate of the Mo-free alloys was decreased with exposure time due to the formation of Cr-rich oxide. Mo addition accelerated the erosion-corrosion because of the erosion of Ni-rich oxide and spallation of oxide scale.