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.

superheater materials

oxidation

oxide scale

Electrochemistry

high-temperature corrosion

p801

rmany

sanicro 28

dry o-2

water-vapor

initial-stages

v56

biomass

kanthal af

Materials Science

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, Environmental Inorganic Chemistry

Lars-Gunnar Johansson

Chalmers, Chemistry and Chemical Engineering, Energy and Material, Environmental Inorganic Chemistry

Mats Halvarsson

Chalmers, Applied Physics, Materials Microstructure

Journal of the Electrochemical Society

0013-4651 (ISSN)

Vol. 162 14 C744-C753

Subject Categories

Metallurgy and Metallic Materials

Areas of Advance

Materials Science

DOI

10.1149/2.0581514jes

More information

Latest update

11/22/2018