The characterization of corrosion layers of GH3535 and Inconel 625 alloys in molten KNO3-NaNO3 salts at 500 degrees C

PUBLICATION: CORROSION SCIENCE
AUTHORS: Liu, Chengpeng; Tang, Xu; Cheng, Long; Leng, Bin; Li, Xiaoli; Ye, Xiang-Xi; Huang, Hefei
 
ABSTRACT
The characterization of corrosion layers of GH3535 and Inconel 625 alloys in the 40 KNO3-60 NaNO3 (wt%) at 500 degrees C 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(NiFe2O4)/MoO2 from outer to inner corrosion layer, while those of Inconel 625 alloy are NiO/Cr2O3 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.