The characterization of corrosion layers of GH3535 and Inconel 625 alloys in molten KNO3-NaNO3 salts at 500 °C. (1st August 2022)

• Record Type: Journal Article
• Authors: Liu, Chengpeng; Tang, Xu; Cheng, Long; Leng, Bin; Li, Xiaoli; Ye, Xiang-Xi; Huang, Hefei
• Is Part Of: Corrosion science. Volume 204(2022)
• Publication Date: 2022-08-01
• Subjects: Nickel-based alloy -- Molten nitrate salts -- Electron microscopy -- Corrosion layers; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110406
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: The characterization of corrosion layers of GH3535 and Inconel 625 alloys in the 40 KNO3 -60 NaNO3 (wt%) at 500 ℃ for 500 h was investigated by advanced electron microscopy. The results show that the corrosion depth of Inconel 625 alloy is smaller than that of GH3535 alloy. The corrosion products of GH3535 alloy are identified to be NiO(NiFe2 O4 )/MoO2 from outer to inner corrosion layer, while those of Inconel 625 alloy are NiO/Cr2 O3 from outer to inner corrosion layer. The corrosion diversity of two alloys can be ascribed to higher content of Mo in GH3535 and Cr in Inconel 625 alloy. Highlights: The structure and composition of corrosion layers are characterized by TEM. The depth of corrosion layer of 625 alloy is thinner than that of GH3535 alloy. The corrosion products of GH3535 alloy are NiO(NiFe2 O4 )/MoO2 . The corrosion products of 625 alloy are NiO/Cr2 O3 . The corrosion diversity is caused by the difference in two alloys composition.