In Situ ESEM Investigation of KCl-Induced Corrosion of a FeCrAl and a Model FeNiCrAl Alloy in Lab Air at 450 degrees C
Journal article, 2015
The very early stages of KCl-induced corrosion of a FeCrAl and a FeNiCrAl alloy in an 0211420 environment were studied using in-situ Environmental Scanning Electron Microscopy (ESEM). The samples were KCl contaminated and then exposed to lab air at a total pressure of 4.8 Ton at 450 degrees C. After exposure, the samples were analyzed using SEM-EDX, FIB and STEM-EDX. For both alloys, fast oxide growth occurred at the KCl particles. Far away from the KCl particles, a thin base oxide formed with potassium chromate nodules on top. The base oxide was layered, consisting of iron-chromium oxide on top and alumina in the bottom part. The FeCrAl alloy suffered internal oxidation while the FeNiCrAl did not. Both alloys formed sub-scale chlorides. A mechanism is proposed for the reaction of KCl on the surface and for the formation of different surface features at the KCl particles.
v56
Materials Science
rmany
initial-stages
kanthal af
p801
water-vapor
superheater materials
sanicro 28
oxide scale
oxidation
biomass
high-temperature corrosion
dry o-2
Electrochemistry
Author
Nooshin Mortazavi Seyedeh
Chalmers, Applied Physics, Materials Microstructure
Luciana Intiso
Chalmers, Applied Physics, Materials Microstructure
Niklas Israelsson
Chalmers, Chemistry and Chemical Engineering, Energy and Material
Lars-Gunnar Johansson
Chalmers, Chemistry and Chemical Engineering, Energy and Material
Mats Halvarsson
Chalmers, Applied Physics, Materials Microstructure
Journal of the Electrochemical Society
0013-4651 (ISSN) 1945-7111 (eISSN)
Vol. 162 14 C744-C753Subject Categories
Metallurgy and Metallic Materials
Areas of Advance
Materials Science
DOI
10.1149/2.0581514jes